lib/test_meminit: fix off-by-one error in test_pages()
[platform/kernel/linux-starfive.git] / drivers / tty / synclink_gt.c
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Device driver for Microgate SyncLink GT serial adapters.
4  *
5  * written by Paul Fulghum for Microgate Corporation
6  * paulkf@microgate.com
7  *
8  * Microgate and SyncLink are trademarks of Microgate Corporation
9  *
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
11  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
12  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
14  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20  * OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22
23 /*
24  * DEBUG OUTPUT DEFINITIONS
25  *
26  * uncomment lines below to enable specific types of debug output
27  *
28  * DBGINFO   information - most verbose output
29  * DBGERR    serious errors
30  * DBGBH     bottom half service routine debugging
31  * DBGISR    interrupt service routine debugging
32  * DBGDATA   output receive and transmit data
33  * DBGTBUF   output transmit DMA buffers and registers
34  * DBGRBUF   output receive DMA buffers and registers
35  */
36
37 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
38 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
39 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
40 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
41 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
42 /*#define DBGTBUF(info) dump_tbufs(info)*/
43 /*#define DBGRBUF(info) dump_rbufs(info)*/
44
45
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/signal.h>
49 #include <linux/sched.h>
50 #include <linux/timer.h>
51 #include <linux/interrupt.h>
52 #include <linux/pci.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 #include <linux/serial.h>
56 #include <linux/major.h>
57 #include <linux/string.h>
58 #include <linux/fcntl.h>
59 #include <linux/ptrace.h>
60 #include <linux/ioport.h>
61 #include <linux/mm.h>
62 #include <linux/seq_file.h>
63 #include <linux/slab.h>
64 #include <linux/netdevice.h>
65 #include <linux/vmalloc.h>
66 #include <linux/init.h>
67 #include <linux/delay.h>
68 #include <linux/ioctl.h>
69 #include <linux/termios.h>
70 #include <linux/bitops.h>
71 #include <linux/workqueue.h>
72 #include <linux/hdlc.h>
73 #include <linux/synclink.h>
74
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 #include <asm/dma.h>
78 #include <asm/types.h>
79 #include <linux/uaccess.h>
80
81 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
82 #define SYNCLINK_GENERIC_HDLC 1
83 #else
84 #define SYNCLINK_GENERIC_HDLC 0
85 #endif
86
87 /*
88  * module identification
89  */
90 static char *driver_name     = "SyncLink GT";
91 static char *slgt_driver_name = "synclink_gt";
92 static char *tty_dev_prefix  = "ttySLG";
93 MODULE_LICENSE("GPL");
94 #define MAX_DEVICES 32
95
96 static const struct pci_device_id pci_table[] = {
97         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
98         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
99         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101         {0,}, /* terminate list */
102 };
103 MODULE_DEVICE_TABLE(pci, pci_table);
104
105 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
106 static void remove_one(struct pci_dev *dev);
107 static struct pci_driver pci_driver = {
108         .name           = "synclink_gt",
109         .id_table       = pci_table,
110         .probe          = init_one,
111         .remove         = remove_one,
112 };
113
114 static bool pci_registered;
115
116 /*
117  * module configuration and status
118  */
119 static struct slgt_info *slgt_device_list;
120 static int slgt_device_count;
121
122 static int ttymajor;
123 static int debug_level;
124 static int maxframe[MAX_DEVICES];
125
126 module_param(ttymajor, int, 0);
127 module_param(debug_level, int, 0);
128 module_param_array(maxframe, int, NULL, 0);
129
130 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
131 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
132 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
133
134 /*
135  * tty support and callbacks
136  */
137 static struct tty_driver *serial_driver;
138
139 static void wait_until_sent(struct tty_struct *tty, int timeout);
140 static void flush_buffer(struct tty_struct *tty);
141 static void tx_release(struct tty_struct *tty);
142
143 /*
144  * generic HDLC support
145  */
146 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
147
148
149 /*
150  * device specific structures, macros and functions
151  */
152
153 #define SLGT_MAX_PORTS 4
154 #define SLGT_REG_SIZE  256
155
156 /*
157  * conditional wait facility
158  */
159 struct cond_wait {
160         struct cond_wait *next;
161         wait_queue_head_t q;
162         wait_queue_entry_t wait;
163         unsigned int data;
164 };
165 static void flush_cond_wait(struct cond_wait **head);
166
167 /*
168  * DMA buffer descriptor and access macros
169  */
170 struct slgt_desc
171 {
172         __le16 count;
173         __le16 status;
174         __le32 pbuf;  /* physical address of data buffer */
175         __le32 next;  /* physical address of next descriptor */
176
177         /* driver book keeping */
178         char *buf;          /* virtual  address of data buffer */
179         unsigned int pdesc; /* physical address of this descriptor */
180         dma_addr_t buf_dma_addr;
181         unsigned short buf_count;
182 };
183
184 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
185 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
186 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
187 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
188 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
189 #define desc_count(a)      (le16_to_cpu((a).count))
190 #define desc_status(a)     (le16_to_cpu((a).status))
191 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
192 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
193 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
194 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
195 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
196
197 struct _input_signal_events {
198         int ri_up;
199         int ri_down;
200         int dsr_up;
201         int dsr_down;
202         int dcd_up;
203         int dcd_down;
204         int cts_up;
205         int cts_down;
206 };
207
208 /*
209  * device instance data structure
210  */
211 struct slgt_info {
212         void *if_ptr;           /* General purpose pointer (used by SPPP) */
213         struct tty_port port;
214
215         struct slgt_info *next_device;  /* device list link */
216
217         char device_name[25];
218         struct pci_dev *pdev;
219
220         int port_count;  /* count of ports on adapter */
221         int adapter_num; /* adapter instance number */
222         int port_num;    /* port instance number */
223
224         /* array of pointers to port contexts on this adapter */
225         struct slgt_info *port_array[SLGT_MAX_PORTS];
226
227         int                     line;           /* tty line instance number */
228
229         struct mgsl_icount      icount;
230
231         int                     timeout;
232         int                     x_char;         /* xon/xoff character */
233         unsigned int            read_status_mask;
234         unsigned int            ignore_status_mask;
235
236         wait_queue_head_t       status_event_wait_q;
237         wait_queue_head_t       event_wait_q;
238         struct timer_list       tx_timer;
239         struct timer_list       rx_timer;
240
241         unsigned int            gpio_present;
242         struct cond_wait        *gpio_wait_q;
243
244         spinlock_t lock;        /* spinlock for synchronizing with ISR */
245
246         struct work_struct task;
247         u32 pending_bh;
248         bool bh_requested;
249         bool bh_running;
250
251         int isr_overflow;
252         bool irq_requested;     /* true if IRQ requested */
253         bool irq_occurred;      /* for diagnostics use */
254
255         /* device configuration */
256
257         unsigned int bus_type;
258         unsigned int irq_level;
259         unsigned long irq_flags;
260
261         unsigned char __iomem * reg_addr;  /* memory mapped registers address */
262         u32 phys_reg_addr;
263         bool reg_addr_requested;
264
265         MGSL_PARAMS params;       /* communications parameters */
266         u32 idle_mode;
267         u32 max_frame_size;       /* as set by device config */
268
269         unsigned int rbuf_fill_level;
270         unsigned int rx_pio;
271         unsigned int if_mode;
272         unsigned int base_clock;
273         unsigned int xsync;
274         unsigned int xctrl;
275
276         /* device status */
277
278         bool rx_enabled;
279         bool rx_restart;
280
281         bool tx_enabled;
282         bool tx_active;
283
284         unsigned char signals;    /* serial signal states */
285         int init_error;  /* initialization error */
286
287         unsigned char *tx_buf;
288         int tx_count;
289
290         char *flag_buf;
291         bool drop_rts_on_tx_done;
292         struct  _input_signal_events    input_signal_events;
293
294         int dcd_chkcount;       /* check counts to prevent */
295         int cts_chkcount;       /* too many IRQs if a signal */
296         int dsr_chkcount;       /* is floating */
297         int ri_chkcount;
298
299         char *bufs;             /* virtual address of DMA buffer lists */
300         dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
301
302         unsigned int rbuf_count;
303         struct slgt_desc *rbufs;
304         unsigned int rbuf_current;
305         unsigned int rbuf_index;
306         unsigned int rbuf_fill_index;
307         unsigned short rbuf_fill_count;
308
309         unsigned int tbuf_count;
310         struct slgt_desc *tbufs;
311         unsigned int tbuf_current;
312         unsigned int tbuf_start;
313
314         unsigned char *tmp_rbuf;
315         unsigned int tmp_rbuf_count;
316
317         /* SPPP/Cisco HDLC device parts */
318
319         int netcount;
320         spinlock_t netlock;
321 #if SYNCLINK_GENERIC_HDLC
322         struct net_device *netdev;
323 #endif
324
325 };
326
327 static MGSL_PARAMS default_params = {
328         .mode            = MGSL_MODE_HDLC,
329         .loopback        = 0,
330         .flags           = HDLC_FLAG_UNDERRUN_ABORT15,
331         .encoding        = HDLC_ENCODING_NRZI_SPACE,
332         .clock_speed     = 0,
333         .addr_filter     = 0xff,
334         .crc_type        = HDLC_CRC_16_CCITT,
335         .preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
336         .preamble        = HDLC_PREAMBLE_PATTERN_NONE,
337         .data_rate       = 9600,
338         .data_bits       = 8,
339         .stop_bits       = 1,
340         .parity          = ASYNC_PARITY_NONE
341 };
342
343
344 #define BH_RECEIVE  1
345 #define BH_TRANSMIT 2
346 #define BH_STATUS   4
347 #define IO_PIN_SHUTDOWN_LIMIT 100
348
349 #define DMABUFSIZE 256
350 #define DESC_LIST_SIZE 4096
351
352 #define MASK_PARITY  BIT1
353 #define MASK_FRAMING BIT0
354 #define MASK_BREAK   BIT14
355 #define MASK_OVERRUN BIT4
356
357 #define GSR   0x00 /* global status */
358 #define JCR   0x04 /* JTAG control */
359 #define IODR  0x08 /* GPIO direction */
360 #define IOER  0x0c /* GPIO interrupt enable */
361 #define IOVR  0x10 /* GPIO value */
362 #define IOSR  0x14 /* GPIO interrupt status */
363 #define TDR   0x80 /* tx data */
364 #define RDR   0x80 /* rx data */
365 #define TCR   0x82 /* tx control */
366 #define TIR   0x84 /* tx idle */
367 #define TPR   0x85 /* tx preamble */
368 #define RCR   0x86 /* rx control */
369 #define VCR   0x88 /* V.24 control */
370 #define CCR   0x89 /* clock control */
371 #define BDR   0x8a /* baud divisor */
372 #define SCR   0x8c /* serial control */
373 #define SSR   0x8e /* serial status */
374 #define RDCSR 0x90 /* rx DMA control/status */
375 #define TDCSR 0x94 /* tx DMA control/status */
376 #define RDDAR 0x98 /* rx DMA descriptor address */
377 #define TDDAR 0x9c /* tx DMA descriptor address */
378 #define XSR   0x40 /* extended sync pattern */
379 #define XCR   0x44 /* extended control */
380
381 #define RXIDLE      BIT14
382 #define RXBREAK     BIT14
383 #define IRQ_TXDATA  BIT13
384 #define IRQ_TXIDLE  BIT12
385 #define IRQ_TXUNDER BIT11 /* HDLC */
386 #define IRQ_RXDATA  BIT10
387 #define IRQ_RXIDLE  BIT9  /* HDLC */
388 #define IRQ_RXBREAK BIT9  /* async */
389 #define IRQ_RXOVER  BIT8
390 #define IRQ_DSR     BIT7
391 #define IRQ_CTS     BIT6
392 #define IRQ_DCD     BIT5
393 #define IRQ_RI      BIT4
394 #define IRQ_ALL     0x3ff0
395 #define IRQ_MASTER  BIT0
396
397 #define slgt_irq_on(info, mask) \
398         wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
399 #define slgt_irq_off(info, mask) \
400         wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
401
402 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
403 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
404 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
405 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
406 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
407 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
408
409 static void  msc_set_vcr(struct slgt_info *info);
410
411 static int  startup(struct slgt_info *info);
412 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
413 static void shutdown(struct slgt_info *info);
414 static void program_hw(struct slgt_info *info);
415 static void change_params(struct slgt_info *info);
416
417 static int  adapter_test(struct slgt_info *info);
418
419 static void reset_port(struct slgt_info *info);
420 static void async_mode(struct slgt_info *info);
421 static void sync_mode(struct slgt_info *info);
422
423 static void rx_stop(struct slgt_info *info);
424 static void rx_start(struct slgt_info *info);
425 static void reset_rbufs(struct slgt_info *info);
426 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
427 static bool rx_get_frame(struct slgt_info *info);
428 static bool rx_get_buf(struct slgt_info *info);
429
430 static void tx_start(struct slgt_info *info);
431 static void tx_stop(struct slgt_info *info);
432 static void tx_set_idle(struct slgt_info *info);
433 static unsigned int tbuf_bytes(struct slgt_info *info);
434 static void reset_tbufs(struct slgt_info *info);
435 static void tdma_reset(struct slgt_info *info);
436 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
437
438 static void get_gtsignals(struct slgt_info *info);
439 static void set_gtsignals(struct slgt_info *info);
440 static void set_rate(struct slgt_info *info, u32 data_rate);
441
442 static void bh_transmit(struct slgt_info *info);
443 static void isr_txeom(struct slgt_info *info, unsigned short status);
444
445 static void tx_timeout(struct timer_list *t);
446 static void rx_timeout(struct timer_list *t);
447
448 /*
449  * ioctl handlers
450  */
451 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
452 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
453 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
454 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
455 static int  set_txidle(struct slgt_info *info, int idle_mode);
456 static int  tx_enable(struct slgt_info *info, int enable);
457 static int  tx_abort(struct slgt_info *info);
458 static int  rx_enable(struct slgt_info *info, int enable);
459 static int  modem_input_wait(struct slgt_info *info,int arg);
460 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
461 static int  get_interface(struct slgt_info *info, int __user *if_mode);
462 static int  set_interface(struct slgt_info *info, int if_mode);
463 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
464 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
465 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
466 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
467 static int  set_xsync(struct slgt_info *info, int if_mode);
468 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
469 static int  set_xctrl(struct slgt_info *info, int if_mode);
470
471 /*
472  * driver functions
473  */
474 static void release_resources(struct slgt_info *info);
475
476 /*
477  * DEBUG OUTPUT CODE
478  */
479 #ifndef DBGINFO
480 #define DBGINFO(fmt)
481 #endif
482 #ifndef DBGERR
483 #define DBGERR(fmt)
484 #endif
485 #ifndef DBGBH
486 #define DBGBH(fmt)
487 #endif
488 #ifndef DBGISR
489 #define DBGISR(fmt)
490 #endif
491
492 #ifdef DBGDATA
493 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
494 {
495         int i;
496         int linecount;
497         printk("%s %s data:\n",info->device_name, label);
498         while(count) {
499                 linecount = (count > 16) ? 16 : count;
500                 for(i=0; i < linecount; i++)
501                         printk("%02X ",(unsigned char)data[i]);
502                 for(;i<17;i++)
503                         printk("   ");
504                 for(i=0;i<linecount;i++) {
505                         if (data[i]>=040 && data[i]<=0176)
506                                 printk("%c",data[i]);
507                         else
508                                 printk(".");
509                 }
510                 printk("\n");
511                 data  += linecount;
512                 count -= linecount;
513         }
514 }
515 #else
516 #define DBGDATA(info, buf, size, label)
517 #endif
518
519 #ifdef DBGTBUF
520 static void dump_tbufs(struct slgt_info *info)
521 {
522         int i;
523         printk("tbuf_current=%d\n", info->tbuf_current);
524         for (i=0 ; i < info->tbuf_count ; i++) {
525                 printk("%d: count=%04X status=%04X\n",
526                         i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
527         }
528 }
529 #else
530 #define DBGTBUF(info)
531 #endif
532
533 #ifdef DBGRBUF
534 static void dump_rbufs(struct slgt_info *info)
535 {
536         int i;
537         printk("rbuf_current=%d\n", info->rbuf_current);
538         for (i=0 ; i < info->rbuf_count ; i++) {
539                 printk("%d: count=%04X status=%04X\n",
540                         i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
541         }
542 }
543 #else
544 #define DBGRBUF(info)
545 #endif
546
547 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
548 {
549 #ifdef SANITY_CHECK
550         if (!info) {
551                 printk("null struct slgt_info for (%s) in %s\n", devname, name);
552                 return 1;
553         }
554 #else
555         if (!info)
556                 return 1;
557 #endif
558         return 0;
559 }
560
561 /*
562  * line discipline callback wrappers
563  *
564  * The wrappers maintain line discipline references
565  * while calling into the line discipline.
566  *
567  * ldisc_receive_buf  - pass receive data to line discipline
568  */
569 static void ldisc_receive_buf(struct tty_struct *tty,
570                               const __u8 *data, char *flags, int count)
571 {
572         struct tty_ldisc *ld;
573         if (!tty)
574                 return;
575         ld = tty_ldisc_ref(tty);
576         if (ld) {
577                 if (ld->ops->receive_buf)
578                         ld->ops->receive_buf(tty, data, flags, count);
579                 tty_ldisc_deref(ld);
580         }
581 }
582
583 /* tty callbacks */
584
585 static int open(struct tty_struct *tty, struct file *filp)
586 {
587         struct slgt_info *info;
588         int retval, line;
589         unsigned long flags;
590
591         line = tty->index;
592         if (line >= slgt_device_count) {
593                 DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
594                 return -ENODEV;
595         }
596
597         info = slgt_device_list;
598         while(info && info->line != line)
599                 info = info->next_device;
600         if (sanity_check(info, tty->name, "open"))
601                 return -ENODEV;
602         if (info->init_error) {
603                 DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
604                 return -ENODEV;
605         }
606
607         tty->driver_data = info;
608         info->port.tty = tty;
609
610         DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
611
612         mutex_lock(&info->port.mutex);
613
614         spin_lock_irqsave(&info->netlock, flags);
615         if (info->netcount) {
616                 retval = -EBUSY;
617                 spin_unlock_irqrestore(&info->netlock, flags);
618                 mutex_unlock(&info->port.mutex);
619                 goto cleanup;
620         }
621         info->port.count++;
622         spin_unlock_irqrestore(&info->netlock, flags);
623
624         if (info->port.count == 1) {
625                 /* 1st open on this device, init hardware */
626                 retval = startup(info);
627                 if (retval < 0) {
628                         mutex_unlock(&info->port.mutex);
629                         goto cleanup;
630                 }
631         }
632         mutex_unlock(&info->port.mutex);
633         retval = block_til_ready(tty, filp, info);
634         if (retval) {
635                 DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
636                 goto cleanup;
637         }
638
639         retval = 0;
640
641 cleanup:
642         if (retval) {
643                 if (tty->count == 1)
644                         info->port.tty = NULL; /* tty layer will release tty struct */
645                 if(info->port.count)
646                         info->port.count--;
647         }
648
649         DBGINFO(("%s open rc=%d\n", info->device_name, retval));
650         return retval;
651 }
652
653 static void close(struct tty_struct *tty, struct file *filp)
654 {
655         struct slgt_info *info = tty->driver_data;
656
657         if (sanity_check(info, tty->name, "close"))
658                 return;
659         DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
660
661         if (tty_port_close_start(&info->port, tty, filp) == 0)
662                 goto cleanup;
663
664         mutex_lock(&info->port.mutex);
665         if (tty_port_initialized(&info->port))
666                 wait_until_sent(tty, info->timeout);
667         flush_buffer(tty);
668         tty_ldisc_flush(tty);
669
670         shutdown(info);
671         mutex_unlock(&info->port.mutex);
672
673         tty_port_close_end(&info->port, tty);
674         info->port.tty = NULL;
675 cleanup:
676         DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
677 }
678
679 static void hangup(struct tty_struct *tty)
680 {
681         struct slgt_info *info = tty->driver_data;
682         unsigned long flags;
683
684         if (sanity_check(info, tty->name, "hangup"))
685                 return;
686         DBGINFO(("%s hangup\n", info->device_name));
687
688         flush_buffer(tty);
689
690         mutex_lock(&info->port.mutex);
691         shutdown(info);
692
693         spin_lock_irqsave(&info->port.lock, flags);
694         info->port.count = 0;
695         info->port.tty = NULL;
696         spin_unlock_irqrestore(&info->port.lock, flags);
697         tty_port_set_active(&info->port, 0);
698         mutex_unlock(&info->port.mutex);
699
700         wake_up_interruptible(&info->port.open_wait);
701 }
702
703 static void set_termios(struct tty_struct *tty,
704                         const struct ktermios *old_termios)
705 {
706         struct slgt_info *info = tty->driver_data;
707         unsigned long flags;
708
709         DBGINFO(("%s set_termios\n", tty->driver->name));
710
711         change_params(info);
712
713         /* Handle transition to B0 status */
714         if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
715                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
716                 spin_lock_irqsave(&info->lock,flags);
717                 set_gtsignals(info);
718                 spin_unlock_irqrestore(&info->lock,flags);
719         }
720
721         /* Handle transition away from B0 status */
722         if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
723                 info->signals |= SerialSignal_DTR;
724                 if (!C_CRTSCTS(tty) || !tty_throttled(tty))
725                         info->signals |= SerialSignal_RTS;
726                 spin_lock_irqsave(&info->lock,flags);
727                 set_gtsignals(info);
728                 spin_unlock_irqrestore(&info->lock,flags);
729         }
730
731         /* Handle turning off CRTSCTS */
732         if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
733                 tty->hw_stopped = 0;
734                 tx_release(tty);
735         }
736 }
737
738 static void update_tx_timer(struct slgt_info *info)
739 {
740         /*
741          * use worst case speed of 1200bps to calculate transmit timeout
742          * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
743          */
744         if (info->params.mode == MGSL_MODE_HDLC) {
745                 int timeout  = (tbuf_bytes(info) * 7) + 1000;
746                 mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
747         }
748 }
749
750 static int write(struct tty_struct *tty,
751                  const unsigned char *buf, int count)
752 {
753         int ret = 0;
754         struct slgt_info *info = tty->driver_data;
755         unsigned long flags;
756
757         if (sanity_check(info, tty->name, "write"))
758                 return -EIO;
759
760         DBGINFO(("%s write count=%d\n", info->device_name, count));
761
762         if (!info->tx_buf || (count > info->max_frame_size))
763                 return -EIO;
764
765         if (!count || tty->flow.stopped || tty->hw_stopped)
766                 return 0;
767
768         spin_lock_irqsave(&info->lock, flags);
769
770         if (info->tx_count) {
771                 /* send accumulated data from send_char() */
772                 if (!tx_load(info, info->tx_buf, info->tx_count))
773                         goto cleanup;
774                 info->tx_count = 0;
775         }
776
777         if (tx_load(info, buf, count))
778                 ret = count;
779
780 cleanup:
781         spin_unlock_irqrestore(&info->lock, flags);
782         DBGINFO(("%s write rc=%d\n", info->device_name, ret));
783         return ret;
784 }
785
786 static int put_char(struct tty_struct *tty, unsigned char ch)
787 {
788         struct slgt_info *info = tty->driver_data;
789         unsigned long flags;
790         int ret = 0;
791
792         if (sanity_check(info, tty->name, "put_char"))
793                 return 0;
794         DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
795         if (!info->tx_buf)
796                 return 0;
797         spin_lock_irqsave(&info->lock,flags);
798         if (info->tx_count < info->max_frame_size) {
799                 info->tx_buf[info->tx_count++] = ch;
800                 ret = 1;
801         }
802         spin_unlock_irqrestore(&info->lock,flags);
803         return ret;
804 }
805
806 static void send_xchar(struct tty_struct *tty, char ch)
807 {
808         struct slgt_info *info = tty->driver_data;
809         unsigned long flags;
810
811         if (sanity_check(info, tty->name, "send_xchar"))
812                 return;
813         DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
814         info->x_char = ch;
815         if (ch) {
816                 spin_lock_irqsave(&info->lock,flags);
817                 if (!info->tx_enabled)
818                         tx_start(info);
819                 spin_unlock_irqrestore(&info->lock,flags);
820         }
821 }
822
823 static void wait_until_sent(struct tty_struct *tty, int timeout)
824 {
825         struct slgt_info *info = tty->driver_data;
826         unsigned long orig_jiffies, char_time;
827
828         if (!info )
829                 return;
830         if (sanity_check(info, tty->name, "wait_until_sent"))
831                 return;
832         DBGINFO(("%s wait_until_sent entry\n", info->device_name));
833         if (!tty_port_initialized(&info->port))
834                 goto exit;
835
836         orig_jiffies = jiffies;
837
838         /* Set check interval to 1/5 of estimated time to
839          * send a character, and make it at least 1. The check
840          * interval should also be less than the timeout.
841          * Note: use tight timings here to satisfy the NIST-PCTS.
842          */
843
844         if (info->params.data_rate) {
845                 char_time = info->timeout/(32 * 5);
846                 if (!char_time)
847                         char_time++;
848         } else
849                 char_time = 1;
850
851         if (timeout)
852                 char_time = min_t(unsigned long, char_time, timeout);
853
854         while (info->tx_active) {
855                 msleep_interruptible(jiffies_to_msecs(char_time));
856                 if (signal_pending(current))
857                         break;
858                 if (timeout && time_after(jiffies, orig_jiffies + timeout))
859                         break;
860         }
861 exit:
862         DBGINFO(("%s wait_until_sent exit\n", info->device_name));
863 }
864
865 static unsigned int write_room(struct tty_struct *tty)
866 {
867         struct slgt_info *info = tty->driver_data;
868         unsigned int ret;
869
870         if (sanity_check(info, tty->name, "write_room"))
871                 return 0;
872         ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
873         DBGINFO(("%s write_room=%u\n", info->device_name, ret));
874         return ret;
875 }
876
877 static void flush_chars(struct tty_struct *tty)
878 {
879         struct slgt_info *info = tty->driver_data;
880         unsigned long flags;
881
882         if (sanity_check(info, tty->name, "flush_chars"))
883                 return;
884         DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
885
886         if (info->tx_count <= 0 || tty->flow.stopped ||
887             tty->hw_stopped || !info->tx_buf)
888                 return;
889
890         DBGINFO(("%s flush_chars start transmit\n", info->device_name));
891
892         spin_lock_irqsave(&info->lock,flags);
893         if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
894                 info->tx_count = 0;
895         spin_unlock_irqrestore(&info->lock,flags);
896 }
897
898 static void flush_buffer(struct tty_struct *tty)
899 {
900         struct slgt_info *info = tty->driver_data;
901         unsigned long flags;
902
903         if (sanity_check(info, tty->name, "flush_buffer"))
904                 return;
905         DBGINFO(("%s flush_buffer\n", info->device_name));
906
907         spin_lock_irqsave(&info->lock, flags);
908         info->tx_count = 0;
909         spin_unlock_irqrestore(&info->lock, flags);
910
911         tty_wakeup(tty);
912 }
913
914 /*
915  * throttle (stop) transmitter
916  */
917 static void tx_hold(struct tty_struct *tty)
918 {
919         struct slgt_info *info = tty->driver_data;
920         unsigned long flags;
921
922         if (sanity_check(info, tty->name, "tx_hold"))
923                 return;
924         DBGINFO(("%s tx_hold\n", info->device_name));
925         spin_lock_irqsave(&info->lock,flags);
926         if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
927                 tx_stop(info);
928         spin_unlock_irqrestore(&info->lock,flags);
929 }
930
931 /*
932  * release (start) transmitter
933  */
934 static void tx_release(struct tty_struct *tty)
935 {
936         struct slgt_info *info = tty->driver_data;
937         unsigned long flags;
938
939         if (sanity_check(info, tty->name, "tx_release"))
940                 return;
941         DBGINFO(("%s tx_release\n", info->device_name));
942         spin_lock_irqsave(&info->lock, flags);
943         if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
944                 info->tx_count = 0;
945         spin_unlock_irqrestore(&info->lock, flags);
946 }
947
948 /*
949  * Service an IOCTL request
950  *
951  * Arguments
952  *
953  *      tty     pointer to tty instance data
954  *      cmd     IOCTL command code
955  *      arg     command argument/context
956  *
957  * Return 0 if success, otherwise error code
958  */
959 static int ioctl(struct tty_struct *tty,
960                  unsigned int cmd, unsigned long arg)
961 {
962         struct slgt_info *info = tty->driver_data;
963         void __user *argp = (void __user *)arg;
964         int ret;
965
966         if (sanity_check(info, tty->name, "ioctl"))
967                 return -ENODEV;
968         DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
969
970         if (cmd != TIOCMIWAIT) {
971                 if (tty_io_error(tty))
972                     return -EIO;
973         }
974
975         switch (cmd) {
976         case MGSL_IOCWAITEVENT:
977                 return wait_mgsl_event(info, argp);
978         case TIOCMIWAIT:
979                 return modem_input_wait(info,(int)arg);
980         case MGSL_IOCSGPIO:
981                 return set_gpio(info, argp);
982         case MGSL_IOCGGPIO:
983                 return get_gpio(info, argp);
984         case MGSL_IOCWAITGPIO:
985                 return wait_gpio(info, argp);
986         case MGSL_IOCGXSYNC:
987                 return get_xsync(info, argp);
988         case MGSL_IOCSXSYNC:
989                 return set_xsync(info, (int)arg);
990         case MGSL_IOCGXCTRL:
991                 return get_xctrl(info, argp);
992         case MGSL_IOCSXCTRL:
993                 return set_xctrl(info, (int)arg);
994         }
995         mutex_lock(&info->port.mutex);
996         switch (cmd) {
997         case MGSL_IOCGPARAMS:
998                 ret = get_params(info, argp);
999                 break;
1000         case MGSL_IOCSPARAMS:
1001                 ret = set_params(info, argp);
1002                 break;
1003         case MGSL_IOCGTXIDLE:
1004                 ret = get_txidle(info, argp);
1005                 break;
1006         case MGSL_IOCSTXIDLE:
1007                 ret = set_txidle(info, (int)arg);
1008                 break;
1009         case MGSL_IOCTXENABLE:
1010                 ret = tx_enable(info, (int)arg);
1011                 break;
1012         case MGSL_IOCRXENABLE:
1013                 ret = rx_enable(info, (int)arg);
1014                 break;
1015         case MGSL_IOCTXABORT:
1016                 ret = tx_abort(info);
1017                 break;
1018         case MGSL_IOCGSTATS:
1019                 ret = get_stats(info, argp);
1020                 break;
1021         case MGSL_IOCGIF:
1022                 ret = get_interface(info, argp);
1023                 break;
1024         case MGSL_IOCSIF:
1025                 ret = set_interface(info,(int)arg);
1026                 break;
1027         default:
1028                 ret = -ENOIOCTLCMD;
1029         }
1030         mutex_unlock(&info->port.mutex);
1031         return ret;
1032 }
1033
1034 static int get_icount(struct tty_struct *tty,
1035                                 struct serial_icounter_struct *icount)
1036
1037 {
1038         struct slgt_info *info = tty->driver_data;
1039         struct mgsl_icount cnow;        /* kernel counter temps */
1040         unsigned long flags;
1041
1042         spin_lock_irqsave(&info->lock,flags);
1043         cnow = info->icount;
1044         spin_unlock_irqrestore(&info->lock,flags);
1045
1046         icount->cts = cnow.cts;
1047         icount->dsr = cnow.dsr;
1048         icount->rng = cnow.rng;
1049         icount->dcd = cnow.dcd;
1050         icount->rx = cnow.rx;
1051         icount->tx = cnow.tx;
1052         icount->frame = cnow.frame;
1053         icount->overrun = cnow.overrun;
1054         icount->parity = cnow.parity;
1055         icount->brk = cnow.brk;
1056         icount->buf_overrun = cnow.buf_overrun;
1057
1058         return 0;
1059 }
1060
1061 /*
1062  * support for 32 bit ioctl calls on 64 bit systems
1063  */
1064 #ifdef CONFIG_COMPAT
1065 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1066 {
1067         struct MGSL_PARAMS32 tmp_params;
1068
1069         DBGINFO(("%s get_params32\n", info->device_name));
1070         memset(&tmp_params, 0, sizeof(tmp_params));
1071         tmp_params.mode            = (compat_ulong_t)info->params.mode;
1072         tmp_params.loopback        = info->params.loopback;
1073         tmp_params.flags           = info->params.flags;
1074         tmp_params.encoding        = info->params.encoding;
1075         tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1076         tmp_params.addr_filter     = info->params.addr_filter;
1077         tmp_params.crc_type        = info->params.crc_type;
1078         tmp_params.preamble_length = info->params.preamble_length;
1079         tmp_params.preamble        = info->params.preamble;
1080         tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1081         tmp_params.data_bits       = info->params.data_bits;
1082         tmp_params.stop_bits       = info->params.stop_bits;
1083         tmp_params.parity          = info->params.parity;
1084         if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1085                 return -EFAULT;
1086         return 0;
1087 }
1088
1089 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1090 {
1091         struct MGSL_PARAMS32 tmp_params;
1092
1093         DBGINFO(("%s set_params32\n", info->device_name));
1094         if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1095                 return -EFAULT;
1096
1097         spin_lock(&info->lock);
1098         if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1099                 info->base_clock = tmp_params.clock_speed;
1100         } else {
1101                 info->params.mode            = tmp_params.mode;
1102                 info->params.loopback        = tmp_params.loopback;
1103                 info->params.flags           = tmp_params.flags;
1104                 info->params.encoding        = tmp_params.encoding;
1105                 info->params.clock_speed     = tmp_params.clock_speed;
1106                 info->params.addr_filter     = tmp_params.addr_filter;
1107                 info->params.crc_type        = tmp_params.crc_type;
1108                 info->params.preamble_length = tmp_params.preamble_length;
1109                 info->params.preamble        = tmp_params.preamble;
1110                 info->params.data_rate       = tmp_params.data_rate;
1111                 info->params.data_bits       = tmp_params.data_bits;
1112                 info->params.stop_bits       = tmp_params.stop_bits;
1113                 info->params.parity          = tmp_params.parity;
1114         }
1115         spin_unlock(&info->lock);
1116
1117         program_hw(info);
1118
1119         return 0;
1120 }
1121
1122 static long slgt_compat_ioctl(struct tty_struct *tty,
1123                          unsigned int cmd, unsigned long arg)
1124 {
1125         struct slgt_info *info = tty->driver_data;
1126         int rc;
1127
1128         if (sanity_check(info, tty->name, "compat_ioctl"))
1129                 return -ENODEV;
1130         DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1131
1132         switch (cmd) {
1133         case MGSL_IOCSPARAMS32:
1134                 rc = set_params32(info, compat_ptr(arg));
1135                 break;
1136
1137         case MGSL_IOCGPARAMS32:
1138                 rc = get_params32(info, compat_ptr(arg));
1139                 break;
1140
1141         case MGSL_IOCGPARAMS:
1142         case MGSL_IOCSPARAMS:
1143         case MGSL_IOCGTXIDLE:
1144         case MGSL_IOCGSTATS:
1145         case MGSL_IOCWAITEVENT:
1146         case MGSL_IOCGIF:
1147         case MGSL_IOCSGPIO:
1148         case MGSL_IOCGGPIO:
1149         case MGSL_IOCWAITGPIO:
1150         case MGSL_IOCGXSYNC:
1151         case MGSL_IOCGXCTRL:
1152                 rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1153                 break;
1154         default:
1155                 rc = ioctl(tty, cmd, arg);
1156         }
1157         DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1158         return rc;
1159 }
1160 #else
1161 #define slgt_compat_ioctl NULL
1162 #endif /* ifdef CONFIG_COMPAT */
1163
1164 /*
1165  * proc fs support
1166  */
1167 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1168 {
1169         char stat_buf[30];
1170         unsigned long flags;
1171
1172         seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1173                       info->device_name, info->phys_reg_addr,
1174                       info->irq_level, info->max_frame_size);
1175
1176         /* output current serial signal states */
1177         spin_lock_irqsave(&info->lock,flags);
1178         get_gtsignals(info);
1179         spin_unlock_irqrestore(&info->lock,flags);
1180
1181         stat_buf[0] = 0;
1182         stat_buf[1] = 0;
1183         if (info->signals & SerialSignal_RTS)
1184                 strcat(stat_buf, "|RTS");
1185         if (info->signals & SerialSignal_CTS)
1186                 strcat(stat_buf, "|CTS");
1187         if (info->signals & SerialSignal_DTR)
1188                 strcat(stat_buf, "|DTR");
1189         if (info->signals & SerialSignal_DSR)
1190                 strcat(stat_buf, "|DSR");
1191         if (info->signals & SerialSignal_DCD)
1192                 strcat(stat_buf, "|CD");
1193         if (info->signals & SerialSignal_RI)
1194                 strcat(stat_buf, "|RI");
1195
1196         if (info->params.mode != MGSL_MODE_ASYNC) {
1197                 seq_printf(m, "\tHDLC txok:%d rxok:%d",
1198                                info->icount.txok, info->icount.rxok);
1199                 if (info->icount.txunder)
1200                         seq_printf(m, " txunder:%d", info->icount.txunder);
1201                 if (info->icount.txabort)
1202                         seq_printf(m, " txabort:%d", info->icount.txabort);
1203                 if (info->icount.rxshort)
1204                         seq_printf(m, " rxshort:%d", info->icount.rxshort);
1205                 if (info->icount.rxlong)
1206                         seq_printf(m, " rxlong:%d", info->icount.rxlong);
1207                 if (info->icount.rxover)
1208                         seq_printf(m, " rxover:%d", info->icount.rxover);
1209                 if (info->icount.rxcrc)
1210                         seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1211         } else {
1212                 seq_printf(m, "\tASYNC tx:%d rx:%d",
1213                                info->icount.tx, info->icount.rx);
1214                 if (info->icount.frame)
1215                         seq_printf(m, " fe:%d", info->icount.frame);
1216                 if (info->icount.parity)
1217                         seq_printf(m, " pe:%d", info->icount.parity);
1218                 if (info->icount.brk)
1219                         seq_printf(m, " brk:%d", info->icount.brk);
1220                 if (info->icount.overrun)
1221                         seq_printf(m, " oe:%d", info->icount.overrun);
1222         }
1223
1224         /* Append serial signal status to end */
1225         seq_printf(m, " %s\n", stat_buf+1);
1226
1227         seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1228                        info->tx_active,info->bh_requested,info->bh_running,
1229                        info->pending_bh);
1230 }
1231
1232 /* Called to print information about devices
1233  */
1234 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1235 {
1236         struct slgt_info *info;
1237
1238         seq_puts(m, "synclink_gt driver\n");
1239
1240         info = slgt_device_list;
1241         while( info ) {
1242                 line_info(m, info);
1243                 info = info->next_device;
1244         }
1245         return 0;
1246 }
1247
1248 /*
1249  * return count of bytes in transmit buffer
1250  */
1251 static unsigned int chars_in_buffer(struct tty_struct *tty)
1252 {
1253         struct slgt_info *info = tty->driver_data;
1254         unsigned int count;
1255         if (sanity_check(info, tty->name, "chars_in_buffer"))
1256                 return 0;
1257         count = tbuf_bytes(info);
1258         DBGINFO(("%s chars_in_buffer()=%u\n", info->device_name, count));
1259         return count;
1260 }
1261
1262 /*
1263  * signal remote device to throttle send data (our receive data)
1264  */
1265 static void throttle(struct tty_struct * tty)
1266 {
1267         struct slgt_info *info = tty->driver_data;
1268         unsigned long flags;
1269
1270         if (sanity_check(info, tty->name, "throttle"))
1271                 return;
1272         DBGINFO(("%s throttle\n", info->device_name));
1273         if (I_IXOFF(tty))
1274                 send_xchar(tty, STOP_CHAR(tty));
1275         if (C_CRTSCTS(tty)) {
1276                 spin_lock_irqsave(&info->lock,flags);
1277                 info->signals &= ~SerialSignal_RTS;
1278                 set_gtsignals(info);
1279                 spin_unlock_irqrestore(&info->lock,flags);
1280         }
1281 }
1282
1283 /*
1284  * signal remote device to stop throttling send data (our receive data)
1285  */
1286 static void unthrottle(struct tty_struct * tty)
1287 {
1288         struct slgt_info *info = tty->driver_data;
1289         unsigned long flags;
1290
1291         if (sanity_check(info, tty->name, "unthrottle"))
1292                 return;
1293         DBGINFO(("%s unthrottle\n", info->device_name));
1294         if (I_IXOFF(tty)) {
1295                 if (info->x_char)
1296                         info->x_char = 0;
1297                 else
1298                         send_xchar(tty, START_CHAR(tty));
1299         }
1300         if (C_CRTSCTS(tty)) {
1301                 spin_lock_irqsave(&info->lock,flags);
1302                 info->signals |= SerialSignal_RTS;
1303                 set_gtsignals(info);
1304                 spin_unlock_irqrestore(&info->lock,flags);
1305         }
1306 }
1307
1308 /*
1309  * set or clear transmit break condition
1310  * break_state  -1=set break condition, 0=clear
1311  */
1312 static int set_break(struct tty_struct *tty, int break_state)
1313 {
1314         struct slgt_info *info = tty->driver_data;
1315         unsigned short value;
1316         unsigned long flags;
1317
1318         if (sanity_check(info, tty->name, "set_break"))
1319                 return -EINVAL;
1320         DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1321
1322         spin_lock_irqsave(&info->lock,flags);
1323         value = rd_reg16(info, TCR);
1324         if (break_state == -1)
1325                 value |= BIT6;
1326         else
1327                 value &= ~BIT6;
1328         wr_reg16(info, TCR, value);
1329         spin_unlock_irqrestore(&info->lock,flags);
1330         return 0;
1331 }
1332
1333 #if SYNCLINK_GENERIC_HDLC
1334
1335 /**
1336  * hdlcdev_attach - called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1337  * @dev:      pointer to network device structure
1338  * @encoding: serial encoding setting
1339  * @parity:   FCS setting
1340  *
1341  * Set encoding and frame check sequence (FCS) options.
1342  *
1343  * Return: 0 if success, otherwise error code
1344  */
1345 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1346                           unsigned short parity)
1347 {
1348         struct slgt_info *info = dev_to_port(dev);
1349         unsigned char  new_encoding;
1350         unsigned short new_crctype;
1351
1352         /* return error if TTY interface open */
1353         if (info->port.count)
1354                 return -EBUSY;
1355
1356         DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1357
1358         switch (encoding)
1359         {
1360         case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1361         case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1362         case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1363         case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1364         case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1365         default: return -EINVAL;
1366         }
1367
1368         switch (parity)
1369         {
1370         case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1371         case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1372         case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1373         default: return -EINVAL;
1374         }
1375
1376         info->params.encoding = new_encoding;
1377         info->params.crc_type = new_crctype;
1378
1379         /* if network interface up, reprogram hardware */
1380         if (info->netcount)
1381                 program_hw(info);
1382
1383         return 0;
1384 }
1385
1386 /**
1387  * hdlcdev_xmit - called by generic HDLC layer to send a frame
1388  * @skb: socket buffer containing HDLC frame
1389  * @dev: pointer to network device structure
1390  */
1391 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1392                                       struct net_device *dev)
1393 {
1394         struct slgt_info *info = dev_to_port(dev);
1395         unsigned long flags;
1396
1397         DBGINFO(("%s hdlc_xmit\n", dev->name));
1398
1399         if (!skb->len)
1400                 return NETDEV_TX_OK;
1401
1402         /* stop sending until this frame completes */
1403         netif_stop_queue(dev);
1404
1405         /* update network statistics */
1406         dev->stats.tx_packets++;
1407         dev->stats.tx_bytes += skb->len;
1408
1409         /* save start time for transmit timeout detection */
1410         netif_trans_update(dev);
1411
1412         spin_lock_irqsave(&info->lock, flags);
1413         tx_load(info, skb->data, skb->len);
1414         spin_unlock_irqrestore(&info->lock, flags);
1415
1416         /* done with socket buffer, so free it */
1417         dev_kfree_skb(skb);
1418
1419         return NETDEV_TX_OK;
1420 }
1421
1422 /**
1423  * hdlcdev_open - called by network layer when interface enabled
1424  * @dev: pointer to network device structure
1425  *
1426  * Claim resources and initialize hardware.
1427  *
1428  * Return: 0 if success, otherwise error code
1429  */
1430 static int hdlcdev_open(struct net_device *dev)
1431 {
1432         struct slgt_info *info = dev_to_port(dev);
1433         int rc;
1434         unsigned long flags;
1435
1436         if (!try_module_get(THIS_MODULE))
1437                 return -EBUSY;
1438
1439         DBGINFO(("%s hdlcdev_open\n", dev->name));
1440
1441         /* generic HDLC layer open processing */
1442         rc = hdlc_open(dev);
1443         if (rc)
1444                 return rc;
1445
1446         /* arbitrate between network and tty opens */
1447         spin_lock_irqsave(&info->netlock, flags);
1448         if (info->port.count != 0 || info->netcount != 0) {
1449                 DBGINFO(("%s hdlc_open busy\n", dev->name));
1450                 spin_unlock_irqrestore(&info->netlock, flags);
1451                 return -EBUSY;
1452         }
1453         info->netcount=1;
1454         spin_unlock_irqrestore(&info->netlock, flags);
1455
1456         /* claim resources and init adapter */
1457         if ((rc = startup(info)) != 0) {
1458                 spin_lock_irqsave(&info->netlock, flags);
1459                 info->netcount=0;
1460                 spin_unlock_irqrestore(&info->netlock, flags);
1461                 return rc;
1462         }
1463
1464         /* assert RTS and DTR, apply hardware settings */
1465         info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1466         program_hw(info);
1467
1468         /* enable network layer transmit */
1469         netif_trans_update(dev);
1470         netif_start_queue(dev);
1471
1472         /* inform generic HDLC layer of current DCD status */
1473         spin_lock_irqsave(&info->lock, flags);
1474         get_gtsignals(info);
1475         spin_unlock_irqrestore(&info->lock, flags);
1476         if (info->signals & SerialSignal_DCD)
1477                 netif_carrier_on(dev);
1478         else
1479                 netif_carrier_off(dev);
1480         return 0;
1481 }
1482
1483 /**
1484  * hdlcdev_close - called by network layer when interface is disabled
1485  * @dev:  pointer to network device structure
1486  *
1487  * Shutdown hardware and release resources.
1488  *
1489  * Return: 0 if success, otherwise error code
1490  */
1491 static int hdlcdev_close(struct net_device *dev)
1492 {
1493         struct slgt_info *info = dev_to_port(dev);
1494         unsigned long flags;
1495
1496         DBGINFO(("%s hdlcdev_close\n", dev->name));
1497
1498         netif_stop_queue(dev);
1499
1500         /* shutdown adapter and release resources */
1501         shutdown(info);
1502
1503         hdlc_close(dev);
1504
1505         spin_lock_irqsave(&info->netlock, flags);
1506         info->netcount=0;
1507         spin_unlock_irqrestore(&info->netlock, flags);
1508
1509         module_put(THIS_MODULE);
1510         return 0;
1511 }
1512
1513 /**
1514  * hdlcdev_ioctl - called by network layer to process IOCTL call to network device
1515  * @dev: pointer to network device structure
1516  * @ifr: pointer to network interface request structure
1517  * @cmd: IOCTL command code
1518  *
1519  * Return: 0 if success, otherwise error code
1520  */
1521 static int hdlcdev_ioctl(struct net_device *dev, struct if_settings *ifs)
1522 {
1523         const size_t size = sizeof(sync_serial_settings);
1524         sync_serial_settings new_line;
1525         sync_serial_settings __user *line = ifs->ifs_ifsu.sync;
1526         struct slgt_info *info = dev_to_port(dev);
1527         unsigned int flags;
1528
1529         DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1530
1531         /* return error if TTY interface open */
1532         if (info->port.count)
1533                 return -EBUSY;
1534
1535         memset(&new_line, 0, sizeof(new_line));
1536
1537         switch (ifs->type) {
1538         case IF_GET_IFACE: /* return current sync_serial_settings */
1539
1540                 ifs->type = IF_IFACE_SYNC_SERIAL;
1541                 if (ifs->size < size) {
1542                         ifs->size = size; /* data size wanted */
1543                         return -ENOBUFS;
1544                 }
1545
1546                 flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1547                                               HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1548                                               HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1549                                               HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1550
1551                 switch (flags){
1552                 case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1553                 case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1554                 case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1555                 case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1556                 default: new_line.clock_type = CLOCK_DEFAULT;
1557                 }
1558
1559                 new_line.clock_rate = info->params.clock_speed;
1560                 new_line.loopback   = info->params.loopback ? 1:0;
1561
1562                 if (copy_to_user(line, &new_line, size))
1563                         return -EFAULT;
1564                 return 0;
1565
1566         case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1567
1568                 if(!capable(CAP_NET_ADMIN))
1569                         return -EPERM;
1570                 if (copy_from_user(&new_line, line, size))
1571                         return -EFAULT;
1572
1573                 switch (new_line.clock_type)
1574                 {
1575                 case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1576                 case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1577                 case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1578                 case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1579                 case CLOCK_DEFAULT:  flags = info->params.flags &
1580                                              (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1581                                               HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1582                                               HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1583                                               HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1584                 default: return -EINVAL;
1585                 }
1586
1587                 if (new_line.loopback != 0 && new_line.loopback != 1)
1588                         return -EINVAL;
1589
1590                 info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1591                                         HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1592                                         HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1593                                         HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1594                 info->params.flags |= flags;
1595
1596                 info->params.loopback = new_line.loopback;
1597
1598                 if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1599                         info->params.clock_speed = new_line.clock_rate;
1600                 else
1601                         info->params.clock_speed = 0;
1602
1603                 /* if network interface up, reprogram hardware */
1604                 if (info->netcount)
1605                         program_hw(info);
1606                 return 0;
1607
1608         default:
1609                 return hdlc_ioctl(dev, ifs);
1610         }
1611 }
1612
1613 /**
1614  * hdlcdev_tx_timeout - called by network layer when transmit timeout is detected
1615  * @dev: pointer to network device structure
1616  * @txqueue: unused
1617  */
1618 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1619 {
1620         struct slgt_info *info = dev_to_port(dev);
1621         unsigned long flags;
1622
1623         DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1624
1625         dev->stats.tx_errors++;
1626         dev->stats.tx_aborted_errors++;
1627
1628         spin_lock_irqsave(&info->lock,flags);
1629         tx_stop(info);
1630         spin_unlock_irqrestore(&info->lock,flags);
1631
1632         netif_wake_queue(dev);
1633 }
1634
1635 /**
1636  * hdlcdev_tx_done - called by device driver when transmit completes
1637  * @info: pointer to device instance information
1638  *
1639  * Reenable network layer transmit if stopped.
1640  */
1641 static void hdlcdev_tx_done(struct slgt_info *info)
1642 {
1643         if (netif_queue_stopped(info->netdev))
1644                 netif_wake_queue(info->netdev);
1645 }
1646
1647 /**
1648  * hdlcdev_rx - called by device driver when frame received
1649  * @info: pointer to device instance information
1650  * @buf:  pointer to buffer contianing frame data
1651  * @size: count of data bytes in buf
1652  *
1653  * Pass frame to network layer.
1654  */
1655 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1656 {
1657         struct sk_buff *skb = dev_alloc_skb(size);
1658         struct net_device *dev = info->netdev;
1659
1660         DBGINFO(("%s hdlcdev_rx\n", dev->name));
1661
1662         if (skb == NULL) {
1663                 DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1664                 dev->stats.rx_dropped++;
1665                 return;
1666         }
1667
1668         skb_put_data(skb, buf, size);
1669
1670         skb->protocol = hdlc_type_trans(skb, dev);
1671
1672         dev->stats.rx_packets++;
1673         dev->stats.rx_bytes += size;
1674
1675         netif_rx(skb);
1676 }
1677
1678 static const struct net_device_ops hdlcdev_ops = {
1679         .ndo_open       = hdlcdev_open,
1680         .ndo_stop       = hdlcdev_close,
1681         .ndo_start_xmit = hdlc_start_xmit,
1682         .ndo_siocwandev = hdlcdev_ioctl,
1683         .ndo_tx_timeout = hdlcdev_tx_timeout,
1684 };
1685
1686 /**
1687  * hdlcdev_init - called by device driver when adding device instance
1688  * @info: pointer to device instance information
1689  *
1690  * Do generic HDLC initialization.
1691  *
1692  * Return: 0 if success, otherwise error code
1693  */
1694 static int hdlcdev_init(struct slgt_info *info)
1695 {
1696         int rc;
1697         struct net_device *dev;
1698         hdlc_device *hdlc;
1699
1700         /* allocate and initialize network and HDLC layer objects */
1701
1702         dev = alloc_hdlcdev(info);
1703         if (!dev) {
1704                 printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1705                 return -ENOMEM;
1706         }
1707
1708         /* for network layer reporting purposes only */
1709         dev->mem_start = info->phys_reg_addr;
1710         dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1711         dev->irq       = info->irq_level;
1712
1713         /* network layer callbacks and settings */
1714         dev->netdev_ops     = &hdlcdev_ops;
1715         dev->watchdog_timeo = 10 * HZ;
1716         dev->tx_queue_len   = 50;
1717
1718         /* generic HDLC layer callbacks and settings */
1719         hdlc         = dev_to_hdlc(dev);
1720         hdlc->attach = hdlcdev_attach;
1721         hdlc->xmit   = hdlcdev_xmit;
1722
1723         /* register objects with HDLC layer */
1724         rc = register_hdlc_device(dev);
1725         if (rc) {
1726                 printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1727                 free_netdev(dev);
1728                 return rc;
1729         }
1730
1731         info->netdev = dev;
1732         return 0;
1733 }
1734
1735 /**
1736  * hdlcdev_exit - called by device driver when removing device instance
1737  * @info: pointer to device instance information
1738  *
1739  * Do generic HDLC cleanup.
1740  */
1741 static void hdlcdev_exit(struct slgt_info *info)
1742 {
1743         if (!info->netdev)
1744                 return;
1745         unregister_hdlc_device(info->netdev);
1746         free_netdev(info->netdev);
1747         info->netdev = NULL;
1748 }
1749
1750 #endif /* ifdef CONFIG_HDLC */
1751
1752 /*
1753  * get async data from rx DMA buffers
1754  */
1755 static void rx_async(struct slgt_info *info)
1756 {
1757         struct mgsl_icount *icount = &info->icount;
1758         unsigned int start, end;
1759         unsigned char *p;
1760         unsigned char status;
1761         struct slgt_desc *bufs = info->rbufs;
1762         int i, count;
1763         int chars = 0;
1764         int stat;
1765         unsigned char ch;
1766
1767         start = end = info->rbuf_current;
1768
1769         while(desc_complete(bufs[end])) {
1770                 count = desc_count(bufs[end]) - info->rbuf_index;
1771                 p     = bufs[end].buf + info->rbuf_index;
1772
1773                 DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1774                 DBGDATA(info, p, count, "rx");
1775
1776                 for(i=0 ; i < count; i+=2, p+=2) {
1777                         ch = *p;
1778                         icount->rx++;
1779
1780                         stat = 0;
1781
1782                         status = *(p + 1) & (BIT1 + BIT0);
1783                         if (status) {
1784                                 if (status & BIT1)
1785                                         icount->parity++;
1786                                 else if (status & BIT0)
1787                                         icount->frame++;
1788                                 /* discard char if tty control flags say so */
1789                                 if (status & info->ignore_status_mask)
1790                                         continue;
1791                                 if (status & BIT1)
1792                                         stat = TTY_PARITY;
1793                                 else if (status & BIT0)
1794                                         stat = TTY_FRAME;
1795                         }
1796                         tty_insert_flip_char(&info->port, ch, stat);
1797                         chars++;
1798                 }
1799
1800                 if (i < count) {
1801                         /* receive buffer not completed */
1802                         info->rbuf_index += i;
1803                         mod_timer(&info->rx_timer, jiffies + 1);
1804                         break;
1805                 }
1806
1807                 info->rbuf_index = 0;
1808                 free_rbufs(info, end, end);
1809
1810                 if (++end == info->rbuf_count)
1811                         end = 0;
1812
1813                 /* if entire list searched then no frame available */
1814                 if (end == start)
1815                         break;
1816         }
1817
1818         if (chars)
1819                 tty_flip_buffer_push(&info->port);
1820 }
1821
1822 /*
1823  * return next bottom half action to perform
1824  */
1825 static int bh_action(struct slgt_info *info)
1826 {
1827         unsigned long flags;
1828         int rc;
1829
1830         spin_lock_irqsave(&info->lock,flags);
1831
1832         if (info->pending_bh & BH_RECEIVE) {
1833                 info->pending_bh &= ~BH_RECEIVE;
1834                 rc = BH_RECEIVE;
1835         } else if (info->pending_bh & BH_TRANSMIT) {
1836                 info->pending_bh &= ~BH_TRANSMIT;
1837                 rc = BH_TRANSMIT;
1838         } else if (info->pending_bh & BH_STATUS) {
1839                 info->pending_bh &= ~BH_STATUS;
1840                 rc = BH_STATUS;
1841         } else {
1842                 /* Mark BH routine as complete */
1843                 info->bh_running = false;
1844                 info->bh_requested = false;
1845                 rc = 0;
1846         }
1847
1848         spin_unlock_irqrestore(&info->lock,flags);
1849
1850         return rc;
1851 }
1852
1853 /*
1854  * perform bottom half processing
1855  */
1856 static void bh_handler(struct work_struct *work)
1857 {
1858         struct slgt_info *info = container_of(work, struct slgt_info, task);
1859         int action;
1860
1861         info->bh_running = true;
1862
1863         while((action = bh_action(info))) {
1864                 switch (action) {
1865                 case BH_RECEIVE:
1866                         DBGBH(("%s bh receive\n", info->device_name));
1867                         switch(info->params.mode) {
1868                         case MGSL_MODE_ASYNC:
1869                                 rx_async(info);
1870                                 break;
1871                         case MGSL_MODE_HDLC:
1872                                 while(rx_get_frame(info));
1873                                 break;
1874                         case MGSL_MODE_RAW:
1875                         case MGSL_MODE_MONOSYNC:
1876                         case MGSL_MODE_BISYNC:
1877                         case MGSL_MODE_XSYNC:
1878                                 while(rx_get_buf(info));
1879                                 break;
1880                         }
1881                         /* restart receiver if rx DMA buffers exhausted */
1882                         if (info->rx_restart)
1883                                 rx_start(info);
1884                         break;
1885                 case BH_TRANSMIT:
1886                         bh_transmit(info);
1887                         break;
1888                 case BH_STATUS:
1889                         DBGBH(("%s bh status\n", info->device_name));
1890                         info->ri_chkcount = 0;
1891                         info->dsr_chkcount = 0;
1892                         info->dcd_chkcount = 0;
1893                         info->cts_chkcount = 0;
1894                         break;
1895                 default:
1896                         DBGBH(("%s unknown action\n", info->device_name));
1897                         break;
1898                 }
1899         }
1900         DBGBH(("%s bh_handler exit\n", info->device_name));
1901 }
1902
1903 static void bh_transmit(struct slgt_info *info)
1904 {
1905         struct tty_struct *tty = info->port.tty;
1906
1907         DBGBH(("%s bh_transmit\n", info->device_name));
1908         if (tty)
1909                 tty_wakeup(tty);
1910 }
1911
1912 static void dsr_change(struct slgt_info *info, unsigned short status)
1913 {
1914         if (status & BIT3) {
1915                 info->signals |= SerialSignal_DSR;
1916                 info->input_signal_events.dsr_up++;
1917         } else {
1918                 info->signals &= ~SerialSignal_DSR;
1919                 info->input_signal_events.dsr_down++;
1920         }
1921         DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1922         if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1923                 slgt_irq_off(info, IRQ_DSR);
1924                 return;
1925         }
1926         info->icount.dsr++;
1927         wake_up_interruptible(&info->status_event_wait_q);
1928         wake_up_interruptible(&info->event_wait_q);
1929         info->pending_bh |= BH_STATUS;
1930 }
1931
1932 static void cts_change(struct slgt_info *info, unsigned short status)
1933 {
1934         if (status & BIT2) {
1935                 info->signals |= SerialSignal_CTS;
1936                 info->input_signal_events.cts_up++;
1937         } else {
1938                 info->signals &= ~SerialSignal_CTS;
1939                 info->input_signal_events.cts_down++;
1940         }
1941         DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
1942         if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1943                 slgt_irq_off(info, IRQ_CTS);
1944                 return;
1945         }
1946         info->icount.cts++;
1947         wake_up_interruptible(&info->status_event_wait_q);
1948         wake_up_interruptible(&info->event_wait_q);
1949         info->pending_bh |= BH_STATUS;
1950
1951         if (tty_port_cts_enabled(&info->port)) {
1952                 if (info->port.tty) {
1953                         if (info->port.tty->hw_stopped) {
1954                                 if (info->signals & SerialSignal_CTS) {
1955                                         info->port.tty->hw_stopped = 0;
1956                                         info->pending_bh |= BH_TRANSMIT;
1957                                         return;
1958                                 }
1959                         } else {
1960                                 if (!(info->signals & SerialSignal_CTS))
1961                                         info->port.tty->hw_stopped = 1;
1962                         }
1963                 }
1964         }
1965 }
1966
1967 static void dcd_change(struct slgt_info *info, unsigned short status)
1968 {
1969         if (status & BIT1) {
1970                 info->signals |= SerialSignal_DCD;
1971                 info->input_signal_events.dcd_up++;
1972         } else {
1973                 info->signals &= ~SerialSignal_DCD;
1974                 info->input_signal_events.dcd_down++;
1975         }
1976         DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
1977         if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1978                 slgt_irq_off(info, IRQ_DCD);
1979                 return;
1980         }
1981         info->icount.dcd++;
1982 #if SYNCLINK_GENERIC_HDLC
1983         if (info->netcount) {
1984                 if (info->signals & SerialSignal_DCD)
1985                         netif_carrier_on(info->netdev);
1986                 else
1987                         netif_carrier_off(info->netdev);
1988         }
1989 #endif
1990         wake_up_interruptible(&info->status_event_wait_q);
1991         wake_up_interruptible(&info->event_wait_q);
1992         info->pending_bh |= BH_STATUS;
1993
1994         if (tty_port_check_carrier(&info->port)) {
1995                 if (info->signals & SerialSignal_DCD)
1996                         wake_up_interruptible(&info->port.open_wait);
1997                 else {
1998                         if (info->port.tty)
1999                                 tty_hangup(info->port.tty);
2000                 }
2001         }
2002 }
2003
2004 static void ri_change(struct slgt_info *info, unsigned short status)
2005 {
2006         if (status & BIT0) {
2007                 info->signals |= SerialSignal_RI;
2008                 info->input_signal_events.ri_up++;
2009         } else {
2010                 info->signals &= ~SerialSignal_RI;
2011                 info->input_signal_events.ri_down++;
2012         }
2013         DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2014         if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2015                 slgt_irq_off(info, IRQ_RI);
2016                 return;
2017         }
2018         info->icount.rng++;
2019         wake_up_interruptible(&info->status_event_wait_q);
2020         wake_up_interruptible(&info->event_wait_q);
2021         info->pending_bh |= BH_STATUS;
2022 }
2023
2024 static void isr_rxdata(struct slgt_info *info)
2025 {
2026         unsigned int count = info->rbuf_fill_count;
2027         unsigned int i = info->rbuf_fill_index;
2028         unsigned short reg;
2029
2030         while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2031                 reg = rd_reg16(info, RDR);
2032                 DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2033                 if (desc_complete(info->rbufs[i])) {
2034                         /* all buffers full */
2035                         rx_stop(info);
2036                         info->rx_restart = true;
2037                         continue;
2038                 }
2039                 info->rbufs[i].buf[count++] = (unsigned char)reg;
2040                 /* async mode saves status byte to buffer for each data byte */
2041                 if (info->params.mode == MGSL_MODE_ASYNC)
2042                         info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2043                 if (count == info->rbuf_fill_level || (reg & BIT10)) {
2044                         /* buffer full or end of frame */
2045                         set_desc_count(info->rbufs[i], count);
2046                         set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2047                         info->rbuf_fill_count = count = 0;
2048                         if (++i == info->rbuf_count)
2049                                 i = 0;
2050                         info->pending_bh |= BH_RECEIVE;
2051                 }
2052         }
2053
2054         info->rbuf_fill_index = i;
2055         info->rbuf_fill_count = count;
2056 }
2057
2058 static void isr_serial(struct slgt_info *info)
2059 {
2060         unsigned short status = rd_reg16(info, SSR);
2061
2062         DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2063
2064         wr_reg16(info, SSR, status); /* clear pending */
2065
2066         info->irq_occurred = true;
2067
2068         if (info->params.mode == MGSL_MODE_ASYNC) {
2069                 if (status & IRQ_TXIDLE) {
2070                         if (info->tx_active)
2071                                 isr_txeom(info, status);
2072                 }
2073                 if (info->rx_pio && (status & IRQ_RXDATA))
2074                         isr_rxdata(info);
2075                 if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2076                         info->icount.brk++;
2077                         /* process break detection if tty control allows */
2078                         if (info->port.tty) {
2079                                 if (!(status & info->ignore_status_mask)) {
2080                                         if (info->read_status_mask & MASK_BREAK) {
2081                                                 tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2082                                                 if (info->port.flags & ASYNC_SAK)
2083                                                         do_SAK(info->port.tty);
2084                                         }
2085                                 }
2086                         }
2087                 }
2088         } else {
2089                 if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2090                         isr_txeom(info, status);
2091                 if (info->rx_pio && (status & IRQ_RXDATA))
2092                         isr_rxdata(info);
2093                 if (status & IRQ_RXIDLE) {
2094                         if (status & RXIDLE)
2095                                 info->icount.rxidle++;
2096                         else
2097                                 info->icount.exithunt++;
2098                         wake_up_interruptible(&info->event_wait_q);
2099                 }
2100
2101                 if (status & IRQ_RXOVER)
2102                         rx_start(info);
2103         }
2104
2105         if (status & IRQ_DSR)
2106                 dsr_change(info, status);
2107         if (status & IRQ_CTS)
2108                 cts_change(info, status);
2109         if (status & IRQ_DCD)
2110                 dcd_change(info, status);
2111         if (status & IRQ_RI)
2112                 ri_change(info, status);
2113 }
2114
2115 static void isr_rdma(struct slgt_info *info)
2116 {
2117         unsigned int status = rd_reg32(info, RDCSR);
2118
2119         DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2120
2121         /* RDCSR (rx DMA control/status)
2122          *
2123          * 31..07  reserved
2124          * 06      save status byte to DMA buffer
2125          * 05      error
2126          * 04      eol (end of list)
2127          * 03      eob (end of buffer)
2128          * 02      IRQ enable
2129          * 01      reset
2130          * 00      enable
2131          */
2132         wr_reg32(info, RDCSR, status);  /* clear pending */
2133
2134         if (status & (BIT5 + BIT4)) {
2135                 DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2136                 info->rx_restart = true;
2137         }
2138         info->pending_bh |= BH_RECEIVE;
2139 }
2140
2141 static void isr_tdma(struct slgt_info *info)
2142 {
2143         unsigned int status = rd_reg32(info, TDCSR);
2144
2145         DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2146
2147         /* TDCSR (tx DMA control/status)
2148          *
2149          * 31..06  reserved
2150          * 05      error
2151          * 04      eol (end of list)
2152          * 03      eob (end of buffer)
2153          * 02      IRQ enable
2154          * 01      reset
2155          * 00      enable
2156          */
2157         wr_reg32(info, TDCSR, status);  /* clear pending */
2158
2159         if (status & (BIT5 + BIT4 + BIT3)) {
2160                 // another transmit buffer has completed
2161                 // run bottom half to get more send data from user
2162                 info->pending_bh |= BH_TRANSMIT;
2163         }
2164 }
2165
2166 /*
2167  * return true if there are unsent tx DMA buffers, otherwise false
2168  *
2169  * if there are unsent buffers then info->tbuf_start
2170  * is set to index of first unsent buffer
2171  */
2172 static bool unsent_tbufs(struct slgt_info *info)
2173 {
2174         unsigned int i = info->tbuf_current;
2175         bool rc = false;
2176
2177         /*
2178          * search backwards from last loaded buffer (precedes tbuf_current)
2179          * for first unsent buffer (desc_count > 0)
2180          */
2181
2182         do {
2183                 if (i)
2184                         i--;
2185                 else
2186                         i = info->tbuf_count - 1;
2187                 if (!desc_count(info->tbufs[i]))
2188                         break;
2189                 info->tbuf_start = i;
2190                 rc = true;
2191         } while (i != info->tbuf_current);
2192
2193         return rc;
2194 }
2195
2196 static void isr_txeom(struct slgt_info *info, unsigned short status)
2197 {
2198         DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2199
2200         slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2201         tdma_reset(info);
2202         if (status & IRQ_TXUNDER) {
2203                 unsigned short val = rd_reg16(info, TCR);
2204                 wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2205                 wr_reg16(info, TCR, val); /* clear reset bit */
2206         }
2207
2208         if (info->tx_active) {
2209                 if (info->params.mode != MGSL_MODE_ASYNC) {
2210                         if (status & IRQ_TXUNDER)
2211                                 info->icount.txunder++;
2212                         else if (status & IRQ_TXIDLE)
2213                                 info->icount.txok++;
2214                 }
2215
2216                 if (unsent_tbufs(info)) {
2217                         tx_start(info);
2218                         update_tx_timer(info);
2219                         return;
2220                 }
2221                 info->tx_active = false;
2222
2223                 del_timer(&info->tx_timer);
2224
2225                 if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2226                         info->signals &= ~SerialSignal_RTS;
2227                         info->drop_rts_on_tx_done = false;
2228                         set_gtsignals(info);
2229                 }
2230
2231 #if SYNCLINK_GENERIC_HDLC
2232                 if (info->netcount)
2233                         hdlcdev_tx_done(info);
2234                 else
2235 #endif
2236                 {
2237                         if (info->port.tty && (info->port.tty->flow.stopped || info->port.tty->hw_stopped)) {
2238                                 tx_stop(info);
2239                                 return;
2240                         }
2241                         info->pending_bh |= BH_TRANSMIT;
2242                 }
2243         }
2244 }
2245
2246 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2247 {
2248         struct cond_wait *w, *prev;
2249
2250         /* wake processes waiting for specific transitions */
2251         for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2252                 if (w->data & changed) {
2253                         w->data = state;
2254                         wake_up_interruptible(&w->q);
2255                         if (prev != NULL)
2256                                 prev->next = w->next;
2257                         else
2258                                 info->gpio_wait_q = w->next;
2259                 } else
2260                         prev = w;
2261         }
2262 }
2263
2264 /* interrupt service routine
2265  *
2266  *      irq     interrupt number
2267  *      dev_id  device ID supplied during interrupt registration
2268  */
2269 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2270 {
2271         struct slgt_info *info = dev_id;
2272         unsigned int gsr;
2273         unsigned int i;
2274
2275         DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2276
2277         while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2278                 DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2279                 info->irq_occurred = true;
2280                 for(i=0; i < info->port_count ; i++) {
2281                         if (info->port_array[i] == NULL)
2282                                 continue;
2283                         spin_lock(&info->port_array[i]->lock);
2284                         if (gsr & (BIT8 << i))
2285                                 isr_serial(info->port_array[i]);
2286                         if (gsr & (BIT16 << (i*2)))
2287                                 isr_rdma(info->port_array[i]);
2288                         if (gsr & (BIT17 << (i*2)))
2289                                 isr_tdma(info->port_array[i]);
2290                         spin_unlock(&info->port_array[i]->lock);
2291                 }
2292         }
2293
2294         if (info->gpio_present) {
2295                 unsigned int state;
2296                 unsigned int changed;
2297                 spin_lock(&info->lock);
2298                 while ((changed = rd_reg32(info, IOSR)) != 0) {
2299                         DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2300                         /* read latched state of GPIO signals */
2301                         state = rd_reg32(info, IOVR);
2302                         /* clear pending GPIO interrupt bits */
2303                         wr_reg32(info, IOSR, changed);
2304                         for (i=0 ; i < info->port_count ; i++) {
2305                                 if (info->port_array[i] != NULL)
2306                                         isr_gpio(info->port_array[i], changed, state);
2307                         }
2308                 }
2309                 spin_unlock(&info->lock);
2310         }
2311
2312         for(i=0; i < info->port_count ; i++) {
2313                 struct slgt_info *port = info->port_array[i];
2314                 if (port == NULL)
2315                         continue;
2316                 spin_lock(&port->lock);
2317                 if ((port->port.count || port->netcount) &&
2318                     port->pending_bh && !port->bh_running &&
2319                     !port->bh_requested) {
2320                         DBGISR(("%s bh queued\n", port->device_name));
2321                         schedule_work(&port->task);
2322                         port->bh_requested = true;
2323                 }
2324                 spin_unlock(&port->lock);
2325         }
2326
2327         DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2328         return IRQ_HANDLED;
2329 }
2330
2331 static int startup(struct slgt_info *info)
2332 {
2333         DBGINFO(("%s startup\n", info->device_name));
2334
2335         if (tty_port_initialized(&info->port))
2336                 return 0;
2337
2338         if (!info->tx_buf) {
2339                 info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2340                 if (!info->tx_buf) {
2341                         DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2342                         return -ENOMEM;
2343                 }
2344         }
2345
2346         info->pending_bh = 0;
2347
2348         memset(&info->icount, 0, sizeof(info->icount));
2349
2350         /* program hardware for current parameters */
2351         change_params(info);
2352
2353         if (info->port.tty)
2354                 clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2355
2356         tty_port_set_initialized(&info->port, 1);
2357
2358         return 0;
2359 }
2360
2361 /*
2362  *  called by close() and hangup() to shutdown hardware
2363  */
2364 static void shutdown(struct slgt_info *info)
2365 {
2366         unsigned long flags;
2367
2368         if (!tty_port_initialized(&info->port))
2369                 return;
2370
2371         DBGINFO(("%s shutdown\n", info->device_name));
2372
2373         /* clear status wait queue because status changes */
2374         /* can't happen after shutting down the hardware */
2375         wake_up_interruptible(&info->status_event_wait_q);
2376         wake_up_interruptible(&info->event_wait_q);
2377
2378         del_timer_sync(&info->tx_timer);
2379         del_timer_sync(&info->rx_timer);
2380
2381         kfree(info->tx_buf);
2382         info->tx_buf = NULL;
2383
2384         spin_lock_irqsave(&info->lock,flags);
2385
2386         tx_stop(info);
2387         rx_stop(info);
2388
2389         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2390
2391         if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2392                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2393                 set_gtsignals(info);
2394         }
2395
2396         flush_cond_wait(&info->gpio_wait_q);
2397
2398         spin_unlock_irqrestore(&info->lock,flags);
2399
2400         if (info->port.tty)
2401                 set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2402
2403         tty_port_set_initialized(&info->port, 0);
2404 }
2405
2406 static void program_hw(struct slgt_info *info)
2407 {
2408         unsigned long flags;
2409
2410         spin_lock_irqsave(&info->lock,flags);
2411
2412         rx_stop(info);
2413         tx_stop(info);
2414
2415         if (info->params.mode != MGSL_MODE_ASYNC ||
2416             info->netcount)
2417                 sync_mode(info);
2418         else
2419                 async_mode(info);
2420
2421         set_gtsignals(info);
2422
2423         info->dcd_chkcount = 0;
2424         info->cts_chkcount = 0;
2425         info->ri_chkcount = 0;
2426         info->dsr_chkcount = 0;
2427
2428         slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2429         get_gtsignals(info);
2430
2431         if (info->netcount ||
2432             (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2433                 rx_start(info);
2434
2435         spin_unlock_irqrestore(&info->lock,flags);
2436 }
2437
2438 /*
2439  * reconfigure adapter based on new parameters
2440  */
2441 static void change_params(struct slgt_info *info)
2442 {
2443         unsigned cflag;
2444         int bits_per_char;
2445
2446         if (!info->port.tty)
2447                 return;
2448         DBGINFO(("%s change_params\n", info->device_name));
2449
2450         cflag = info->port.tty->termios.c_cflag;
2451
2452         /* if B0 rate (hangup) specified then negate RTS and DTR */
2453         /* otherwise assert RTS and DTR */
2454         if (cflag & CBAUD)
2455                 info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2456         else
2457                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2458
2459         /* byte size and parity */
2460
2461         info->params.data_bits = tty_get_char_size(cflag);
2462         info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2463
2464         if (cflag & PARENB)
2465                 info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2466         else
2467                 info->params.parity = ASYNC_PARITY_NONE;
2468
2469         /* calculate number of jiffies to transmit a full
2470          * FIFO (32 bytes) at specified data rate
2471          */
2472         bits_per_char = info->params.data_bits +
2473                         info->params.stop_bits + 1;
2474
2475         info->params.data_rate = tty_get_baud_rate(info->port.tty);
2476
2477         if (info->params.data_rate) {
2478                 info->timeout = (32*HZ*bits_per_char) /
2479                                 info->params.data_rate;
2480         }
2481         info->timeout += HZ/50;         /* Add .02 seconds of slop */
2482
2483         tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2484         tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2485
2486         /* process tty input control flags */
2487
2488         info->read_status_mask = IRQ_RXOVER;
2489         if (I_INPCK(info->port.tty))
2490                 info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2491         if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2492                 info->read_status_mask |= MASK_BREAK;
2493         if (I_IGNPAR(info->port.tty))
2494                 info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2495         if (I_IGNBRK(info->port.tty)) {
2496                 info->ignore_status_mask |= MASK_BREAK;
2497                 /* If ignoring parity and break indicators, ignore
2498                  * overruns too.  (For real raw support).
2499                  */
2500                 if (I_IGNPAR(info->port.tty))
2501                         info->ignore_status_mask |= MASK_OVERRUN;
2502         }
2503
2504         program_hw(info);
2505 }
2506
2507 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2508 {
2509         DBGINFO(("%s get_stats\n",  info->device_name));
2510         if (!user_icount) {
2511                 memset(&info->icount, 0, sizeof(info->icount));
2512         } else {
2513                 if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2514                         return -EFAULT;
2515         }
2516         return 0;
2517 }
2518
2519 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2520 {
2521         DBGINFO(("%s get_params\n", info->device_name));
2522         if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2523                 return -EFAULT;
2524         return 0;
2525 }
2526
2527 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2528 {
2529         unsigned long flags;
2530         MGSL_PARAMS tmp_params;
2531
2532         DBGINFO(("%s set_params\n", info->device_name));
2533         if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2534                 return -EFAULT;
2535
2536         spin_lock_irqsave(&info->lock, flags);
2537         if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2538                 info->base_clock = tmp_params.clock_speed;
2539         else
2540                 memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2541         spin_unlock_irqrestore(&info->lock, flags);
2542
2543         program_hw(info);
2544
2545         return 0;
2546 }
2547
2548 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2549 {
2550         DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2551         if (put_user(info->idle_mode, idle_mode))
2552                 return -EFAULT;
2553         return 0;
2554 }
2555
2556 static int set_txidle(struct slgt_info *info, int idle_mode)
2557 {
2558         unsigned long flags;
2559         DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2560         spin_lock_irqsave(&info->lock,flags);
2561         info->idle_mode = idle_mode;
2562         if (info->params.mode != MGSL_MODE_ASYNC)
2563                 tx_set_idle(info);
2564         spin_unlock_irqrestore(&info->lock,flags);
2565         return 0;
2566 }
2567
2568 static int tx_enable(struct slgt_info *info, int enable)
2569 {
2570         unsigned long flags;
2571         DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2572         spin_lock_irqsave(&info->lock,flags);
2573         if (enable) {
2574                 if (!info->tx_enabled)
2575                         tx_start(info);
2576         } else {
2577                 if (info->tx_enabled)
2578                         tx_stop(info);
2579         }
2580         spin_unlock_irqrestore(&info->lock,flags);
2581         return 0;
2582 }
2583
2584 /*
2585  * abort transmit HDLC frame
2586  */
2587 static int tx_abort(struct slgt_info *info)
2588 {
2589         unsigned long flags;
2590         DBGINFO(("%s tx_abort\n", info->device_name));
2591         spin_lock_irqsave(&info->lock,flags);
2592         tdma_reset(info);
2593         spin_unlock_irqrestore(&info->lock,flags);
2594         return 0;
2595 }
2596
2597 static int rx_enable(struct slgt_info *info, int enable)
2598 {
2599         unsigned long flags;
2600         unsigned int rbuf_fill_level;
2601         DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2602         spin_lock_irqsave(&info->lock,flags);
2603         /*
2604          * enable[31..16] = receive DMA buffer fill level
2605          * 0 = noop (leave fill level unchanged)
2606          * fill level must be multiple of 4 and <= buffer size
2607          */
2608         rbuf_fill_level = ((unsigned int)enable) >> 16;
2609         if (rbuf_fill_level) {
2610                 if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2611                         spin_unlock_irqrestore(&info->lock, flags);
2612                         return -EINVAL;
2613                 }
2614                 info->rbuf_fill_level = rbuf_fill_level;
2615                 if (rbuf_fill_level < 128)
2616                         info->rx_pio = 1; /* PIO mode */
2617                 else
2618                         info->rx_pio = 0; /* DMA mode */
2619                 rx_stop(info); /* restart receiver to use new fill level */
2620         }
2621
2622         /*
2623          * enable[1..0] = receiver enable command
2624          * 0 = disable
2625          * 1 = enable
2626          * 2 = enable or force hunt mode if already enabled
2627          */
2628         enable &= 3;
2629         if (enable) {
2630                 if (!info->rx_enabled)
2631                         rx_start(info);
2632                 else if (enable == 2) {
2633                         /* force hunt mode (write 1 to RCR[3]) */
2634                         wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2635                 }
2636         } else {
2637                 if (info->rx_enabled)
2638                         rx_stop(info);
2639         }
2640         spin_unlock_irqrestore(&info->lock,flags);
2641         return 0;
2642 }
2643
2644 /*
2645  *  wait for specified event to occur
2646  */
2647 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2648 {
2649         unsigned long flags;
2650         int s;
2651         int rc=0;
2652         struct mgsl_icount cprev, cnow;
2653         int events;
2654         int mask;
2655         struct  _input_signal_events oldsigs, newsigs;
2656         DECLARE_WAITQUEUE(wait, current);
2657
2658         if (get_user(mask, mask_ptr))
2659                 return -EFAULT;
2660
2661         DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2662
2663         spin_lock_irqsave(&info->lock,flags);
2664
2665         /* return immediately if state matches requested events */
2666         get_gtsignals(info);
2667         s = info->signals;
2668
2669         events = mask &
2670                 ( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2671                   ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2672                   ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2673                   ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2674         if (events) {
2675                 spin_unlock_irqrestore(&info->lock,flags);
2676                 goto exit;
2677         }
2678
2679         /* save current irq counts */
2680         cprev = info->icount;
2681         oldsigs = info->input_signal_events;
2682
2683         /* enable hunt and idle irqs if needed */
2684         if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2685                 unsigned short val = rd_reg16(info, SCR);
2686                 if (!(val & IRQ_RXIDLE))
2687                         wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2688         }
2689
2690         set_current_state(TASK_INTERRUPTIBLE);
2691         add_wait_queue(&info->event_wait_q, &wait);
2692
2693         spin_unlock_irqrestore(&info->lock,flags);
2694
2695         for(;;) {
2696                 schedule();
2697                 if (signal_pending(current)) {
2698                         rc = -ERESTARTSYS;
2699                         break;
2700                 }
2701
2702                 /* get current irq counts */
2703                 spin_lock_irqsave(&info->lock,flags);
2704                 cnow = info->icount;
2705                 newsigs = info->input_signal_events;
2706                 set_current_state(TASK_INTERRUPTIBLE);
2707                 spin_unlock_irqrestore(&info->lock,flags);
2708
2709                 /* if no change, wait aborted for some reason */
2710                 if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2711                     newsigs.dsr_down == oldsigs.dsr_down &&
2712                     newsigs.dcd_up   == oldsigs.dcd_up   &&
2713                     newsigs.dcd_down == oldsigs.dcd_down &&
2714                     newsigs.cts_up   == oldsigs.cts_up   &&
2715                     newsigs.cts_down == oldsigs.cts_down &&
2716                     newsigs.ri_up    == oldsigs.ri_up    &&
2717                     newsigs.ri_down  == oldsigs.ri_down  &&
2718                     cnow.exithunt    == cprev.exithunt   &&
2719                     cnow.rxidle      == cprev.rxidle) {
2720                         rc = -EIO;
2721                         break;
2722                 }
2723
2724                 events = mask &
2725                         ( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2726                           (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2727                           (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2728                           (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2729                           (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2730                           (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2731                           (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2732                           (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2733                           (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2734                           (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2735                 if (events)
2736                         break;
2737
2738                 cprev = cnow;
2739                 oldsigs = newsigs;
2740         }
2741
2742         remove_wait_queue(&info->event_wait_q, &wait);
2743         set_current_state(TASK_RUNNING);
2744
2745
2746         if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2747                 spin_lock_irqsave(&info->lock,flags);
2748                 if (!waitqueue_active(&info->event_wait_q)) {
2749                         /* disable enable exit hunt mode/idle rcvd IRQs */
2750                         wr_reg16(info, SCR,
2751                                 (unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2752                 }
2753                 spin_unlock_irqrestore(&info->lock,flags);
2754         }
2755 exit:
2756         if (rc == 0)
2757                 rc = put_user(events, mask_ptr);
2758         return rc;
2759 }
2760
2761 static int get_interface(struct slgt_info *info, int __user *if_mode)
2762 {
2763         DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2764         if (put_user(info->if_mode, if_mode))
2765                 return -EFAULT;
2766         return 0;
2767 }
2768
2769 static int set_interface(struct slgt_info *info, int if_mode)
2770 {
2771         unsigned long flags;
2772         unsigned short val;
2773
2774         DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2775         spin_lock_irqsave(&info->lock,flags);
2776         info->if_mode = if_mode;
2777
2778         msc_set_vcr(info);
2779
2780         /* TCR (tx control) 07  1=RTS driver control */
2781         val = rd_reg16(info, TCR);
2782         if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2783                 val |= BIT7;
2784         else
2785                 val &= ~BIT7;
2786         wr_reg16(info, TCR, val);
2787
2788         spin_unlock_irqrestore(&info->lock,flags);
2789         return 0;
2790 }
2791
2792 static int get_xsync(struct slgt_info *info, int __user *xsync)
2793 {
2794         DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2795         if (put_user(info->xsync, xsync))
2796                 return -EFAULT;
2797         return 0;
2798 }
2799
2800 /*
2801  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2802  *
2803  * sync pattern is contained in least significant bytes of value
2804  * most significant byte of sync pattern is oldest (1st sent/detected)
2805  */
2806 static int set_xsync(struct slgt_info *info, int xsync)
2807 {
2808         unsigned long flags;
2809
2810         DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2811         spin_lock_irqsave(&info->lock, flags);
2812         info->xsync = xsync;
2813         wr_reg32(info, XSR, xsync);
2814         spin_unlock_irqrestore(&info->lock, flags);
2815         return 0;
2816 }
2817
2818 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2819 {
2820         DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2821         if (put_user(info->xctrl, xctrl))
2822                 return -EFAULT;
2823         return 0;
2824 }
2825
2826 /*
2827  * set extended control options
2828  *
2829  * xctrl[31:19] reserved, must be zero
2830  * xctrl[18:17] extended sync pattern length in bytes
2831  *              00 = 1 byte  in xsr[7:0]
2832  *              01 = 2 bytes in xsr[15:0]
2833  *              10 = 3 bytes in xsr[23:0]
2834  *              11 = 4 bytes in xsr[31:0]
2835  * xctrl[16]    1 = enable terminal count, 0=disabled
2836  * xctrl[15:0]  receive terminal count for fixed length packets
2837  *              value is count minus one (0 = 1 byte packet)
2838  *              when terminal count is reached, receiver
2839  *              automatically returns to hunt mode and receive
2840  *              FIFO contents are flushed to DMA buffers with
2841  *              end of frame (EOF) status
2842  */
2843 static int set_xctrl(struct slgt_info *info, int xctrl)
2844 {
2845         unsigned long flags;
2846
2847         DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2848         spin_lock_irqsave(&info->lock, flags);
2849         info->xctrl = xctrl;
2850         wr_reg32(info, XCR, xctrl);
2851         spin_unlock_irqrestore(&info->lock, flags);
2852         return 0;
2853 }
2854
2855 /*
2856  * set general purpose IO pin state and direction
2857  *
2858  * user_gpio fields:
2859  * state   each bit indicates a pin state
2860  * smask   set bit indicates pin state to set
2861  * dir     each bit indicates a pin direction (0=input, 1=output)
2862  * dmask   set bit indicates pin direction to set
2863  */
2864 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2865 {
2866         unsigned long flags;
2867         struct gpio_desc gpio;
2868         __u32 data;
2869
2870         if (!info->gpio_present)
2871                 return -EINVAL;
2872         if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2873                 return -EFAULT;
2874         DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2875                  info->device_name, gpio.state, gpio.smask,
2876                  gpio.dir, gpio.dmask));
2877
2878         spin_lock_irqsave(&info->port_array[0]->lock, flags);
2879         if (gpio.dmask) {
2880                 data = rd_reg32(info, IODR);
2881                 data |= gpio.dmask & gpio.dir;
2882                 data &= ~(gpio.dmask & ~gpio.dir);
2883                 wr_reg32(info, IODR, data);
2884         }
2885         if (gpio.smask) {
2886                 data = rd_reg32(info, IOVR);
2887                 data |= gpio.smask & gpio.state;
2888                 data &= ~(gpio.smask & ~gpio.state);
2889                 wr_reg32(info, IOVR, data);
2890         }
2891         spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2892
2893         return 0;
2894 }
2895
2896 /*
2897  * get general purpose IO pin state and direction
2898  */
2899 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2900 {
2901         struct gpio_desc gpio;
2902         if (!info->gpio_present)
2903                 return -EINVAL;
2904         gpio.state = rd_reg32(info, IOVR);
2905         gpio.smask = 0xffffffff;
2906         gpio.dir   = rd_reg32(info, IODR);
2907         gpio.dmask = 0xffffffff;
2908         if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2909                 return -EFAULT;
2910         DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2911                  info->device_name, gpio.state, gpio.dir));
2912         return 0;
2913 }
2914
2915 /*
2916  * conditional wait facility
2917  */
2918 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2919 {
2920         init_waitqueue_head(&w->q);
2921         init_waitqueue_entry(&w->wait, current);
2922         w->data = data;
2923 }
2924
2925 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2926 {
2927         set_current_state(TASK_INTERRUPTIBLE);
2928         add_wait_queue(&w->q, &w->wait);
2929         w->next = *head;
2930         *head = w;
2931 }
2932
2933 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
2934 {
2935         struct cond_wait *w, *prev;
2936         remove_wait_queue(&cw->q, &cw->wait);
2937         set_current_state(TASK_RUNNING);
2938         for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
2939                 if (w == cw) {
2940                         if (prev != NULL)
2941                                 prev->next = w->next;
2942                         else
2943                                 *head = w->next;
2944                         break;
2945                 }
2946         }
2947 }
2948
2949 static void flush_cond_wait(struct cond_wait **head)
2950 {
2951         while (*head != NULL) {
2952                 wake_up_interruptible(&(*head)->q);
2953                 *head = (*head)->next;
2954         }
2955 }
2956
2957 /*
2958  * wait for general purpose I/O pin(s) to enter specified state
2959  *
2960  * user_gpio fields:
2961  * state - bit indicates target pin state
2962  * smask - set bit indicates watched pin
2963  *
2964  * The wait ends when at least one watched pin enters the specified
2965  * state. When 0 (no error) is returned, user_gpio->state is set to the
2966  * state of all GPIO pins when the wait ends.
2967  *
2968  * Note: Each pin may be a dedicated input, dedicated output, or
2969  * configurable input/output. The number and configuration of pins
2970  * varies with the specific adapter model. Only input pins (dedicated
2971  * or configured) can be monitored with this function.
2972  */
2973 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2974 {
2975         unsigned long flags;
2976         int rc = 0;
2977         struct gpio_desc gpio;
2978         struct cond_wait wait;
2979         u32 state;
2980
2981         if (!info->gpio_present)
2982                 return -EINVAL;
2983         if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2984                 return -EFAULT;
2985         DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
2986                  info->device_name, gpio.state, gpio.smask));
2987         /* ignore output pins identified by set IODR bit */
2988         if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
2989                 return -EINVAL;
2990         init_cond_wait(&wait, gpio.smask);
2991
2992         spin_lock_irqsave(&info->port_array[0]->lock, flags);
2993         /* enable interrupts for watched pins */
2994         wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
2995         /* get current pin states */
2996         state = rd_reg32(info, IOVR);
2997
2998         if (gpio.smask & ~(state ^ gpio.state)) {
2999                 /* already in target state */
3000                 gpio.state = state;
3001         } else {
3002                 /* wait for target state */
3003                 add_cond_wait(&info->gpio_wait_q, &wait);
3004                 spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3005                 schedule();
3006                 if (signal_pending(current))
3007                         rc = -ERESTARTSYS;
3008                 else
3009                         gpio.state = wait.data;
3010                 spin_lock_irqsave(&info->port_array[0]->lock, flags);
3011                 remove_cond_wait(&info->gpio_wait_q, &wait);
3012         }
3013
3014         /* disable all GPIO interrupts if no waiting processes */
3015         if (info->gpio_wait_q == NULL)
3016                 wr_reg32(info, IOER, 0);
3017         spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3018
3019         if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3020                 rc = -EFAULT;
3021         return rc;
3022 }
3023
3024 static int modem_input_wait(struct slgt_info *info,int arg)
3025 {
3026         unsigned long flags;
3027         int rc;
3028         struct mgsl_icount cprev, cnow;
3029         DECLARE_WAITQUEUE(wait, current);
3030
3031         /* save current irq counts */
3032         spin_lock_irqsave(&info->lock,flags);
3033         cprev = info->icount;
3034         add_wait_queue(&info->status_event_wait_q, &wait);
3035         set_current_state(TASK_INTERRUPTIBLE);
3036         spin_unlock_irqrestore(&info->lock,flags);
3037
3038         for(;;) {
3039                 schedule();
3040                 if (signal_pending(current)) {
3041                         rc = -ERESTARTSYS;
3042                         break;
3043                 }
3044
3045                 /* get new irq counts */
3046                 spin_lock_irqsave(&info->lock,flags);
3047                 cnow = info->icount;
3048                 set_current_state(TASK_INTERRUPTIBLE);
3049                 spin_unlock_irqrestore(&info->lock,flags);
3050
3051                 /* if no change, wait aborted for some reason */
3052                 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3053                     cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3054                         rc = -EIO;
3055                         break;
3056                 }
3057
3058                 /* check for change in caller specified modem input */
3059                 if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3060                     (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3061                     (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3062                     (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3063                         rc = 0;
3064                         break;
3065                 }
3066
3067                 cprev = cnow;
3068         }
3069         remove_wait_queue(&info->status_event_wait_q, &wait);
3070         set_current_state(TASK_RUNNING);
3071         return rc;
3072 }
3073
3074 /*
3075  *  return state of serial control and status signals
3076  */
3077 static int tiocmget(struct tty_struct *tty)
3078 {
3079         struct slgt_info *info = tty->driver_data;
3080         unsigned int result;
3081         unsigned long flags;
3082
3083         spin_lock_irqsave(&info->lock,flags);
3084         get_gtsignals(info);
3085         spin_unlock_irqrestore(&info->lock,flags);
3086
3087         result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3088                 ((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3089                 ((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3090                 ((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3091                 ((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3092                 ((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3093
3094         DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3095         return result;
3096 }
3097
3098 /*
3099  * set modem control signals (DTR/RTS)
3100  *
3101  *      cmd     signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3102  *              TIOCMSET = set/clear signal values
3103  *      value   bit mask for command
3104  */
3105 static int tiocmset(struct tty_struct *tty,
3106                     unsigned int set, unsigned int clear)
3107 {
3108         struct slgt_info *info = tty->driver_data;
3109         unsigned long flags;
3110
3111         DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3112
3113         if (set & TIOCM_RTS)
3114                 info->signals |= SerialSignal_RTS;
3115         if (set & TIOCM_DTR)
3116                 info->signals |= SerialSignal_DTR;
3117         if (clear & TIOCM_RTS)
3118                 info->signals &= ~SerialSignal_RTS;
3119         if (clear & TIOCM_DTR)
3120                 info->signals &= ~SerialSignal_DTR;
3121
3122         spin_lock_irqsave(&info->lock,flags);
3123         set_gtsignals(info);
3124         spin_unlock_irqrestore(&info->lock,flags);
3125         return 0;
3126 }
3127
3128 static int carrier_raised(struct tty_port *port)
3129 {
3130         unsigned long flags;
3131         struct slgt_info *info = container_of(port, struct slgt_info, port);
3132
3133         spin_lock_irqsave(&info->lock,flags);
3134         get_gtsignals(info);
3135         spin_unlock_irqrestore(&info->lock,flags);
3136         return (info->signals & SerialSignal_DCD) ? 1 : 0;
3137 }
3138
3139 static void dtr_rts(struct tty_port *port, int on)
3140 {
3141         unsigned long flags;
3142         struct slgt_info *info = container_of(port, struct slgt_info, port);
3143
3144         spin_lock_irqsave(&info->lock,flags);
3145         if (on)
3146                 info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3147         else
3148                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3149         set_gtsignals(info);
3150         spin_unlock_irqrestore(&info->lock,flags);
3151 }
3152
3153
3154 /*
3155  *  block current process until the device is ready to open
3156  */
3157 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3158                            struct slgt_info *info)
3159 {
3160         DECLARE_WAITQUEUE(wait, current);
3161         int             retval;
3162         bool            do_clocal = false;
3163         unsigned long   flags;
3164         int             cd;
3165         struct tty_port *port = &info->port;
3166
3167         DBGINFO(("%s block_til_ready\n", tty->driver->name));
3168
3169         if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3170                 /* nonblock mode is set or port is not enabled */
3171                 tty_port_set_active(port, 1);
3172                 return 0;
3173         }
3174
3175         if (C_CLOCAL(tty))
3176                 do_clocal = true;
3177
3178         /* Wait for carrier detect and the line to become
3179          * free (i.e., not in use by the callout).  While we are in
3180          * this loop, port->count is dropped by one, so that
3181          * close() knows when to free things.  We restore it upon
3182          * exit, either normal or abnormal.
3183          */
3184
3185         retval = 0;
3186         add_wait_queue(&port->open_wait, &wait);
3187
3188         spin_lock_irqsave(&info->lock, flags);
3189         port->count--;
3190         spin_unlock_irqrestore(&info->lock, flags);
3191         port->blocked_open++;
3192
3193         while (1) {
3194                 if (C_BAUD(tty) && tty_port_initialized(port))
3195                         tty_port_raise_dtr_rts(port);
3196
3197                 set_current_state(TASK_INTERRUPTIBLE);
3198
3199                 if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3200                         retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3201                                         -EAGAIN : -ERESTARTSYS;
3202                         break;
3203                 }
3204
3205                 cd = tty_port_carrier_raised(port);
3206                 if (do_clocal || cd)
3207                         break;
3208
3209                 if (signal_pending(current)) {
3210                         retval = -ERESTARTSYS;
3211                         break;
3212                 }
3213
3214                 DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3215                 tty_unlock(tty);
3216                 schedule();
3217                 tty_lock(tty);
3218         }
3219
3220         set_current_state(TASK_RUNNING);
3221         remove_wait_queue(&port->open_wait, &wait);
3222
3223         if (!tty_hung_up_p(filp))
3224                 port->count++;
3225         port->blocked_open--;
3226
3227         if (!retval)
3228                 tty_port_set_active(port, 1);
3229
3230         DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3231         return retval;
3232 }
3233
3234 /*
3235  * allocate buffers used for calling line discipline receive_buf
3236  * directly in synchronous mode
3237  * note: add 5 bytes to max frame size to allow appending
3238  * 32-bit CRC and status byte when configured to do so
3239  */
3240 static int alloc_tmp_rbuf(struct slgt_info *info)
3241 {
3242         info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3243         if (info->tmp_rbuf == NULL)
3244                 return -ENOMEM;
3245         /* unused flag buffer to satisfy receive_buf calling interface */
3246         info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3247         if (!info->flag_buf) {
3248                 kfree(info->tmp_rbuf);
3249                 info->tmp_rbuf = NULL;
3250                 return -ENOMEM;
3251         }
3252         return 0;
3253 }
3254
3255 static void free_tmp_rbuf(struct slgt_info *info)
3256 {
3257         kfree(info->tmp_rbuf);
3258         info->tmp_rbuf = NULL;
3259         kfree(info->flag_buf);
3260         info->flag_buf = NULL;
3261 }
3262
3263 /*
3264  * allocate DMA descriptor lists.
3265  */
3266 static int alloc_desc(struct slgt_info *info)
3267 {
3268         unsigned int i;
3269         unsigned int pbufs;
3270
3271         /* allocate memory to hold descriptor lists */
3272         info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3273                                         &info->bufs_dma_addr, GFP_KERNEL);
3274         if (info->bufs == NULL)
3275                 return -ENOMEM;
3276
3277         info->rbufs = (struct slgt_desc*)info->bufs;
3278         info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3279
3280         pbufs = (unsigned int)info->bufs_dma_addr;
3281
3282         /*
3283          * Build circular lists of descriptors
3284          */
3285
3286         for (i=0; i < info->rbuf_count; i++) {
3287                 /* physical address of this descriptor */
3288                 info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3289
3290                 /* physical address of next descriptor */
3291                 if (i == info->rbuf_count - 1)
3292                         info->rbufs[i].next = cpu_to_le32(pbufs);
3293                 else
3294                         info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3295                 set_desc_count(info->rbufs[i], DMABUFSIZE);
3296         }
3297
3298         for (i=0; i < info->tbuf_count; i++) {
3299                 /* physical address of this descriptor */
3300                 info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3301
3302                 /* physical address of next descriptor */
3303                 if (i == info->tbuf_count - 1)
3304                         info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3305                 else
3306                         info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3307         }
3308
3309         return 0;
3310 }
3311
3312 static void free_desc(struct slgt_info *info)
3313 {
3314         if (info->bufs != NULL) {
3315                 dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3316                                   info->bufs, info->bufs_dma_addr);
3317                 info->bufs  = NULL;
3318                 info->rbufs = NULL;
3319                 info->tbufs = NULL;
3320         }
3321 }
3322
3323 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3324 {
3325         int i;
3326         for (i=0; i < count; i++) {
3327                 bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3328                                                  &bufs[i].buf_dma_addr, GFP_KERNEL);
3329                 if (!bufs[i].buf)
3330                         return -ENOMEM;
3331                 bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3332         }
3333         return 0;
3334 }
3335
3336 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3337 {
3338         int i;
3339         for (i=0; i < count; i++) {
3340                 if (bufs[i].buf == NULL)
3341                         continue;
3342                 dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3343                                   bufs[i].buf_dma_addr);
3344                 bufs[i].buf = NULL;
3345         }
3346 }
3347
3348 static int alloc_dma_bufs(struct slgt_info *info)
3349 {
3350         info->rbuf_count = 32;
3351         info->tbuf_count = 32;
3352
3353         if (alloc_desc(info) < 0 ||
3354             alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3355             alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3356             alloc_tmp_rbuf(info) < 0) {
3357                 DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3358                 return -ENOMEM;
3359         }
3360         reset_rbufs(info);
3361         return 0;
3362 }
3363
3364 static void free_dma_bufs(struct slgt_info *info)
3365 {
3366         if (info->bufs) {
3367                 free_bufs(info, info->rbufs, info->rbuf_count);
3368                 free_bufs(info, info->tbufs, info->tbuf_count);
3369                 free_desc(info);
3370         }
3371         free_tmp_rbuf(info);
3372 }
3373
3374 static int claim_resources(struct slgt_info *info)
3375 {
3376         if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3377                 DBGERR(("%s reg addr conflict, addr=%08X\n",
3378                         info->device_name, info->phys_reg_addr));
3379                 info->init_error = DiagStatus_AddressConflict;
3380                 goto errout;
3381         }
3382         else
3383                 info->reg_addr_requested = true;
3384
3385         info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3386         if (!info->reg_addr) {
3387                 DBGERR(("%s can't map device registers, addr=%08X\n",
3388                         info->device_name, info->phys_reg_addr));
3389                 info->init_error = DiagStatus_CantAssignPciResources;
3390                 goto errout;
3391         }
3392         return 0;
3393
3394 errout:
3395         release_resources(info);
3396         return -ENODEV;
3397 }
3398
3399 static void release_resources(struct slgt_info *info)
3400 {
3401         if (info->irq_requested) {
3402                 free_irq(info->irq_level, info);
3403                 info->irq_requested = false;
3404         }
3405
3406         if (info->reg_addr_requested) {
3407                 release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3408                 info->reg_addr_requested = false;
3409         }
3410
3411         if (info->reg_addr) {
3412                 iounmap(info->reg_addr);
3413                 info->reg_addr = NULL;
3414         }
3415 }
3416
3417 /* Add the specified device instance data structure to the
3418  * global linked list of devices and increment the device count.
3419  */
3420 static void add_device(struct slgt_info *info)
3421 {
3422         char *devstr;
3423
3424         info->next_device = NULL;
3425         info->line = slgt_device_count;
3426         sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3427
3428         if (info->line < MAX_DEVICES) {
3429                 if (maxframe[info->line])
3430                         info->max_frame_size = maxframe[info->line];
3431         }
3432
3433         slgt_device_count++;
3434
3435         if (!slgt_device_list)
3436                 slgt_device_list = info;
3437         else {
3438                 struct slgt_info *current_dev = slgt_device_list;
3439                 while(current_dev->next_device)
3440                         current_dev = current_dev->next_device;
3441                 current_dev->next_device = info;
3442         }
3443
3444         if (info->max_frame_size < 4096)
3445                 info->max_frame_size = 4096;
3446         else if (info->max_frame_size > 65535)
3447                 info->max_frame_size = 65535;
3448
3449         switch(info->pdev->device) {
3450         case SYNCLINK_GT_DEVICE_ID:
3451                 devstr = "GT";
3452                 break;
3453         case SYNCLINK_GT2_DEVICE_ID:
3454                 devstr = "GT2";
3455                 break;
3456         case SYNCLINK_GT4_DEVICE_ID:
3457                 devstr = "GT4";
3458                 break;
3459         case SYNCLINK_AC_DEVICE_ID:
3460                 devstr = "AC";
3461                 info->params.mode = MGSL_MODE_ASYNC;
3462                 break;
3463         default:
3464                 devstr = "(unknown model)";
3465         }
3466         printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3467                 devstr, info->device_name, info->phys_reg_addr,
3468                 info->irq_level, info->max_frame_size);
3469
3470 #if SYNCLINK_GENERIC_HDLC
3471         hdlcdev_init(info);
3472 #endif
3473 }
3474
3475 static const struct tty_port_operations slgt_port_ops = {
3476         .carrier_raised = carrier_raised,
3477         .dtr_rts = dtr_rts,
3478 };
3479
3480 /*
3481  *  allocate device instance structure, return NULL on failure
3482  */
3483 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3484 {
3485         struct slgt_info *info;
3486
3487         info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3488
3489         if (!info) {
3490                 DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3491                         driver_name, adapter_num, port_num));
3492         } else {
3493                 tty_port_init(&info->port);
3494                 info->port.ops = &slgt_port_ops;
3495                 INIT_WORK(&info->task, bh_handler);
3496                 info->max_frame_size = 4096;
3497                 info->base_clock = 14745600;
3498                 info->rbuf_fill_level = DMABUFSIZE;
3499                 init_waitqueue_head(&info->status_event_wait_q);
3500                 init_waitqueue_head(&info->event_wait_q);
3501                 spin_lock_init(&info->netlock);
3502                 memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3503                 info->idle_mode = HDLC_TXIDLE_FLAGS;
3504                 info->adapter_num = adapter_num;
3505                 info->port_num = port_num;
3506
3507                 timer_setup(&info->tx_timer, tx_timeout, 0);
3508                 timer_setup(&info->rx_timer, rx_timeout, 0);
3509
3510                 /* Copy configuration info to device instance data */
3511                 info->pdev = pdev;
3512                 info->irq_level = pdev->irq;
3513                 info->phys_reg_addr = pci_resource_start(pdev,0);
3514
3515                 info->bus_type = MGSL_BUS_TYPE_PCI;
3516                 info->irq_flags = IRQF_SHARED;
3517
3518                 info->init_error = -1; /* assume error, set to 0 on successful init */
3519         }
3520
3521         return info;
3522 }
3523
3524 static void device_init(int adapter_num, struct pci_dev *pdev)
3525 {
3526         struct slgt_info *port_array[SLGT_MAX_PORTS];
3527         int i;
3528         int port_count = 1;
3529
3530         if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3531                 port_count = 2;
3532         else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3533                 port_count = 4;
3534
3535         /* allocate device instances for all ports */
3536         for (i=0; i < port_count; ++i) {
3537                 port_array[i] = alloc_dev(adapter_num, i, pdev);
3538                 if (port_array[i] == NULL) {
3539                         for (--i; i >= 0; --i) {
3540                                 tty_port_destroy(&port_array[i]->port);
3541                                 kfree(port_array[i]);
3542                         }
3543                         return;
3544                 }
3545         }
3546
3547         /* give copy of port_array to all ports and add to device list  */
3548         for (i=0; i < port_count; ++i) {
3549                 memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3550                 add_device(port_array[i]);
3551                 port_array[i]->port_count = port_count;
3552                 spin_lock_init(&port_array[i]->lock);
3553         }
3554
3555         /* Allocate and claim adapter resources */
3556         if (!claim_resources(port_array[0])) {
3557
3558                 alloc_dma_bufs(port_array[0]);
3559
3560                 /* copy resource information from first port to others */
3561                 for (i = 1; i < port_count; ++i) {
3562                         port_array[i]->irq_level = port_array[0]->irq_level;
3563                         port_array[i]->reg_addr  = port_array[0]->reg_addr;
3564                         alloc_dma_bufs(port_array[i]);
3565                 }
3566
3567                 if (request_irq(port_array[0]->irq_level,
3568                                         slgt_interrupt,
3569                                         port_array[0]->irq_flags,
3570                                         port_array[0]->device_name,
3571                                         port_array[0]) < 0) {
3572                         DBGERR(("%s request_irq failed IRQ=%d\n",
3573                                 port_array[0]->device_name,
3574                                 port_array[0]->irq_level));
3575                 } else {
3576                         port_array[0]->irq_requested = true;
3577                         adapter_test(port_array[0]);
3578                         for (i=1 ; i < port_count ; i++) {
3579                                 port_array[i]->init_error = port_array[0]->init_error;
3580                                 port_array[i]->gpio_present = port_array[0]->gpio_present;
3581                         }
3582                 }
3583         }
3584
3585         for (i = 0; i < port_count; ++i) {
3586                 struct slgt_info *info = port_array[i];
3587                 tty_port_register_device(&info->port, serial_driver, info->line,
3588                                 &info->pdev->dev);
3589         }
3590 }
3591
3592 static int init_one(struct pci_dev *dev,
3593                               const struct pci_device_id *ent)
3594 {
3595         if (pci_enable_device(dev)) {
3596                 printk("error enabling pci device %p\n", dev);
3597                 return -EIO;
3598         }
3599         pci_set_master(dev);
3600         device_init(slgt_device_count, dev);
3601         return 0;
3602 }
3603
3604 static void remove_one(struct pci_dev *dev)
3605 {
3606 }
3607
3608 static const struct tty_operations ops = {
3609         .open = open,
3610         .close = close,
3611         .write = write,
3612         .put_char = put_char,
3613         .flush_chars = flush_chars,
3614         .write_room = write_room,
3615         .chars_in_buffer = chars_in_buffer,
3616         .flush_buffer = flush_buffer,
3617         .ioctl = ioctl,
3618         .compat_ioctl = slgt_compat_ioctl,
3619         .throttle = throttle,
3620         .unthrottle = unthrottle,
3621         .send_xchar = send_xchar,
3622         .break_ctl = set_break,
3623         .wait_until_sent = wait_until_sent,
3624         .set_termios = set_termios,
3625         .stop = tx_hold,
3626         .start = tx_release,
3627         .hangup = hangup,
3628         .tiocmget = tiocmget,
3629         .tiocmset = tiocmset,
3630         .get_icount = get_icount,
3631         .proc_show = synclink_gt_proc_show,
3632 };
3633
3634 static void slgt_cleanup(void)
3635 {
3636         struct slgt_info *info;
3637         struct slgt_info *tmp;
3638
3639         printk(KERN_INFO "unload %s\n", driver_name);
3640
3641         if (serial_driver) {
3642                 for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3643                         tty_unregister_device(serial_driver, info->line);
3644                 tty_unregister_driver(serial_driver);
3645                 tty_driver_kref_put(serial_driver);
3646         }
3647
3648         /* reset devices */
3649         info = slgt_device_list;
3650         while(info) {
3651                 reset_port(info);
3652                 info = info->next_device;
3653         }
3654
3655         /* release devices */
3656         info = slgt_device_list;
3657         while(info) {
3658 #if SYNCLINK_GENERIC_HDLC
3659                 hdlcdev_exit(info);
3660 #endif
3661                 free_dma_bufs(info);
3662                 free_tmp_rbuf(info);
3663                 if (info->port_num == 0)
3664                         release_resources(info);
3665                 tmp = info;
3666                 info = info->next_device;
3667                 tty_port_destroy(&tmp->port);
3668                 kfree(tmp);
3669         }
3670
3671         if (pci_registered)
3672                 pci_unregister_driver(&pci_driver);
3673 }
3674
3675 /*
3676  *  Driver initialization entry point.
3677  */
3678 static int __init slgt_init(void)
3679 {
3680         int rc;
3681
3682         printk(KERN_INFO "%s\n", driver_name);
3683
3684         serial_driver = tty_alloc_driver(MAX_DEVICES, TTY_DRIVER_REAL_RAW |
3685                         TTY_DRIVER_DYNAMIC_DEV);
3686         if (IS_ERR(serial_driver)) {
3687                 printk("%s can't allocate tty driver\n", driver_name);
3688                 return PTR_ERR(serial_driver);
3689         }
3690
3691         /* Initialize the tty_driver structure */
3692
3693         serial_driver->driver_name = slgt_driver_name;
3694         serial_driver->name = tty_dev_prefix;
3695         serial_driver->major = ttymajor;
3696         serial_driver->minor_start = 64;
3697         serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3698         serial_driver->subtype = SERIAL_TYPE_NORMAL;
3699         serial_driver->init_termios = tty_std_termios;
3700         serial_driver->init_termios.c_cflag =
3701                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3702         serial_driver->init_termios.c_ispeed = 9600;
3703         serial_driver->init_termios.c_ospeed = 9600;
3704         tty_set_operations(serial_driver, &ops);
3705         if ((rc = tty_register_driver(serial_driver)) < 0) {
3706                 DBGERR(("%s can't register serial driver\n", driver_name));
3707                 tty_driver_kref_put(serial_driver);
3708                 serial_driver = NULL;
3709                 goto error;
3710         }
3711
3712         printk(KERN_INFO "%s, tty major#%d\n",
3713                driver_name, serial_driver->major);
3714
3715         slgt_device_count = 0;
3716         if ((rc = pci_register_driver(&pci_driver)) < 0) {
3717                 printk("%s pci_register_driver error=%d\n", driver_name, rc);
3718                 goto error;
3719         }
3720         pci_registered = true;
3721
3722         if (!slgt_device_list)
3723                 printk("%s no devices found\n",driver_name);
3724
3725         return 0;
3726
3727 error:
3728         slgt_cleanup();
3729         return rc;
3730 }
3731
3732 static void __exit slgt_exit(void)
3733 {
3734         slgt_cleanup();
3735 }
3736
3737 module_init(slgt_init);
3738 module_exit(slgt_exit);
3739
3740 /*
3741  * register access routines
3742  */
3743
3744 #define CALC_REGADDR() \
3745         unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3746         if (addr >= 0x80) \
3747                 reg_addr += (info->port_num) * 32; \
3748         else if (addr >= 0x40)  \
3749                 reg_addr += (info->port_num) * 16;
3750
3751 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3752 {
3753         CALC_REGADDR();
3754         return readb((void __iomem *)reg_addr);
3755 }
3756
3757 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3758 {
3759         CALC_REGADDR();
3760         writeb(value, (void __iomem *)reg_addr);
3761 }
3762
3763 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3764 {
3765         CALC_REGADDR();
3766         return readw((void __iomem *)reg_addr);
3767 }
3768
3769 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3770 {
3771         CALC_REGADDR();
3772         writew(value, (void __iomem *)reg_addr);
3773 }
3774
3775 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3776 {
3777         CALC_REGADDR();
3778         return readl((void __iomem *)reg_addr);
3779 }
3780
3781 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3782 {
3783         CALC_REGADDR();
3784         writel(value, (void __iomem *)reg_addr);
3785 }
3786
3787 static void rdma_reset(struct slgt_info *info)
3788 {
3789         unsigned int i;
3790
3791         /* set reset bit */
3792         wr_reg32(info, RDCSR, BIT1);
3793
3794         /* wait for enable bit cleared */
3795         for(i=0 ; i < 1000 ; i++)
3796                 if (!(rd_reg32(info, RDCSR) & BIT0))
3797                         break;
3798 }
3799
3800 static void tdma_reset(struct slgt_info *info)
3801 {
3802         unsigned int i;
3803
3804         /* set reset bit */
3805         wr_reg32(info, TDCSR, BIT1);
3806
3807         /* wait for enable bit cleared */
3808         for(i=0 ; i < 1000 ; i++)
3809                 if (!(rd_reg32(info, TDCSR) & BIT0))
3810                         break;
3811 }
3812
3813 /*
3814  * enable internal loopback
3815  * TxCLK and RxCLK are generated from BRG
3816  * and TxD is looped back to RxD internally.
3817  */
3818 static void enable_loopback(struct slgt_info *info)
3819 {
3820         /* SCR (serial control) BIT2=loopback enable */
3821         wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3822
3823         if (info->params.mode != MGSL_MODE_ASYNC) {
3824                 /* CCR (clock control)
3825                  * 07..05  tx clock source (010 = BRG)
3826                  * 04..02  rx clock source (010 = BRG)
3827                  * 01      auxclk enable   (0 = disable)
3828                  * 00      BRG enable      (1 = enable)
3829                  *
3830                  * 0100 1001
3831                  */
3832                 wr_reg8(info, CCR, 0x49);
3833
3834                 /* set speed if available, otherwise use default */
3835                 if (info->params.clock_speed)
3836                         set_rate(info, info->params.clock_speed);
3837                 else
3838                         set_rate(info, 3686400);
3839         }
3840 }
3841
3842 /*
3843  *  set baud rate generator to specified rate
3844  */
3845 static void set_rate(struct slgt_info *info, u32 rate)
3846 {
3847         unsigned int div;
3848         unsigned int osc = info->base_clock;
3849
3850         /* div = osc/rate - 1
3851          *
3852          * Round div up if osc/rate is not integer to
3853          * force to next slowest rate.
3854          */
3855
3856         if (rate) {
3857                 div = osc/rate;
3858                 if (!(osc % rate) && div)
3859                         div--;
3860                 wr_reg16(info, BDR, (unsigned short)div);
3861         }
3862 }
3863
3864 static void rx_stop(struct slgt_info *info)
3865 {
3866         unsigned short val;
3867
3868         /* disable and reset receiver */
3869         val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3870         wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3871         wr_reg16(info, RCR, val);                  /* clear reset bit */
3872
3873         slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3874
3875         /* clear pending rx interrupts */
3876         wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3877
3878         rdma_reset(info);
3879
3880         info->rx_enabled = false;
3881         info->rx_restart = false;
3882 }
3883
3884 static void rx_start(struct slgt_info *info)
3885 {
3886         unsigned short val;
3887
3888         slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3889
3890         /* clear pending rx overrun IRQ */
3891         wr_reg16(info, SSR, IRQ_RXOVER);
3892
3893         /* reset and disable receiver */
3894         val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3895         wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3896         wr_reg16(info, RCR, val);                  /* clear reset bit */
3897
3898         rdma_reset(info);
3899         reset_rbufs(info);
3900
3901         if (info->rx_pio) {
3902                 /* rx request when rx FIFO not empty */
3903                 wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3904                 slgt_irq_on(info, IRQ_RXDATA);
3905                 if (info->params.mode == MGSL_MODE_ASYNC) {
3906                         /* enable saving of rx status */
3907                         wr_reg32(info, RDCSR, BIT6);
3908                 }
3909         } else {
3910                 /* rx request when rx FIFO half full */
3911                 wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3912                 /* set 1st descriptor address */
3913                 wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3914
3915                 if (info->params.mode != MGSL_MODE_ASYNC) {
3916                         /* enable rx DMA and DMA interrupt */
3917                         wr_reg32(info, RDCSR, (BIT2 + BIT0));
3918                 } else {
3919                         /* enable saving of rx status, rx DMA and DMA interrupt */
3920                         wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3921                 }
3922         }
3923
3924         slgt_irq_on(info, IRQ_RXOVER);
3925
3926         /* enable receiver */
3927         wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
3928
3929         info->rx_restart = false;
3930         info->rx_enabled = true;
3931 }
3932
3933 static void tx_start(struct slgt_info *info)
3934 {
3935         if (!info->tx_enabled) {
3936                 wr_reg16(info, TCR,
3937                          (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
3938                 info->tx_enabled = true;
3939         }
3940
3941         if (desc_count(info->tbufs[info->tbuf_start])) {
3942                 info->drop_rts_on_tx_done = false;
3943
3944                 if (info->params.mode != MGSL_MODE_ASYNC) {
3945                         if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
3946                                 get_gtsignals(info);
3947                                 if (!(info->signals & SerialSignal_RTS)) {
3948                                         info->signals |= SerialSignal_RTS;
3949                                         set_gtsignals(info);
3950                                         info->drop_rts_on_tx_done = true;
3951                                 }
3952                         }
3953
3954                         slgt_irq_off(info, IRQ_TXDATA);
3955                         slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
3956                         /* clear tx idle and underrun status bits */
3957                         wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3958                 } else {
3959                         slgt_irq_off(info, IRQ_TXDATA);
3960                         slgt_irq_on(info, IRQ_TXIDLE);
3961                         /* clear tx idle status bit */
3962                         wr_reg16(info, SSR, IRQ_TXIDLE);
3963                 }
3964                 /* set 1st descriptor address and start DMA */
3965                 wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
3966                 wr_reg32(info, TDCSR, BIT2 + BIT0);
3967                 info->tx_active = true;
3968         }
3969 }
3970
3971 static void tx_stop(struct slgt_info *info)
3972 {
3973         unsigned short val;
3974
3975         del_timer(&info->tx_timer);
3976
3977         tdma_reset(info);
3978
3979         /* reset and disable transmitter */
3980         val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
3981         wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
3982
3983         slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
3984
3985         /* clear tx idle and underrun status bit */
3986         wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3987
3988         reset_tbufs(info);
3989
3990         info->tx_enabled = false;
3991         info->tx_active = false;
3992 }
3993
3994 static void reset_port(struct slgt_info *info)
3995 {
3996         if (!info->reg_addr)
3997                 return;
3998
3999         tx_stop(info);
4000         rx_stop(info);
4001
4002         info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4003         set_gtsignals(info);
4004
4005         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4006 }
4007
4008 static void reset_adapter(struct slgt_info *info)
4009 {
4010         int i;
4011         for (i=0; i < info->port_count; ++i) {
4012                 if (info->port_array[i])
4013                         reset_port(info->port_array[i]);
4014         }
4015 }
4016
4017 static void async_mode(struct slgt_info *info)
4018 {
4019         unsigned short val;
4020
4021         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4022         tx_stop(info);
4023         rx_stop(info);
4024
4025         /* TCR (tx control)
4026          *
4027          * 15..13  mode, 010=async
4028          * 12..10  encoding, 000=NRZ
4029          * 09      parity enable
4030          * 08      1=odd parity, 0=even parity
4031          * 07      1=RTS driver control
4032          * 06      1=break enable
4033          * 05..04  character length
4034          *         00=5 bits
4035          *         01=6 bits
4036          *         10=7 bits
4037          *         11=8 bits
4038          * 03      0=1 stop bit, 1=2 stop bits
4039          * 02      reset
4040          * 01      enable
4041          * 00      auto-CTS enable
4042          */
4043         val = 0x4000;
4044
4045         if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4046                 val |= BIT7;
4047
4048         if (info->params.parity != ASYNC_PARITY_NONE) {
4049                 val |= BIT9;
4050                 if (info->params.parity == ASYNC_PARITY_ODD)
4051                         val |= BIT8;
4052         }
4053
4054         switch (info->params.data_bits)
4055         {
4056         case 6: val |= BIT4; break;
4057         case 7: val |= BIT5; break;
4058         case 8: val |= BIT5 + BIT4; break;
4059         }
4060
4061         if (info->params.stop_bits != 1)
4062                 val |= BIT3;
4063
4064         if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4065                 val |= BIT0;
4066
4067         wr_reg16(info, TCR, val);
4068
4069         /* RCR (rx control)
4070          *
4071          * 15..13  mode, 010=async
4072          * 12..10  encoding, 000=NRZ
4073          * 09      parity enable
4074          * 08      1=odd parity, 0=even parity
4075          * 07..06  reserved, must be 0
4076          * 05..04  character length
4077          *         00=5 bits
4078          *         01=6 bits
4079          *         10=7 bits
4080          *         11=8 bits
4081          * 03      reserved, must be zero
4082          * 02      reset
4083          * 01      enable
4084          * 00      auto-DCD enable
4085          */
4086         val = 0x4000;
4087
4088         if (info->params.parity != ASYNC_PARITY_NONE) {
4089                 val |= BIT9;
4090                 if (info->params.parity == ASYNC_PARITY_ODD)
4091                         val |= BIT8;
4092         }
4093
4094         switch (info->params.data_bits)
4095         {
4096         case 6: val |= BIT4; break;
4097         case 7: val |= BIT5; break;
4098         case 8: val |= BIT5 + BIT4; break;
4099         }
4100
4101         if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4102                 val |= BIT0;
4103
4104         wr_reg16(info, RCR, val);
4105
4106         /* CCR (clock control)
4107          *
4108          * 07..05  011 = tx clock source is BRG/16
4109          * 04..02  010 = rx clock source is BRG
4110          * 01      0 = auxclk disabled
4111          * 00      1 = BRG enabled
4112          *
4113          * 0110 1001
4114          */
4115         wr_reg8(info, CCR, 0x69);
4116
4117         msc_set_vcr(info);
4118
4119         /* SCR (serial control)
4120          *
4121          * 15  1=tx req on FIFO half empty
4122          * 14  1=rx req on FIFO half full
4123          * 13  tx data  IRQ enable
4124          * 12  tx idle  IRQ enable
4125          * 11  rx break on IRQ enable
4126          * 10  rx data  IRQ enable
4127          * 09  rx break off IRQ enable
4128          * 08  overrun  IRQ enable
4129          * 07  DSR      IRQ enable
4130          * 06  CTS      IRQ enable
4131          * 05  DCD      IRQ enable
4132          * 04  RI       IRQ enable
4133          * 03  0=16x sampling, 1=8x sampling
4134          * 02  1=txd->rxd internal loopback enable
4135          * 01  reserved, must be zero
4136          * 00  1=master IRQ enable
4137          */
4138         val = BIT15 + BIT14 + BIT0;
4139         /* JCR[8] : 1 = x8 async mode feature available */
4140         if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4141             ((info->base_clock < (info->params.data_rate * 16)) ||
4142              (info->base_clock % (info->params.data_rate * 16)))) {
4143                 /* use 8x sampling */
4144                 val |= BIT3;
4145                 set_rate(info, info->params.data_rate * 8);
4146         } else {
4147                 /* use 16x sampling */
4148                 set_rate(info, info->params.data_rate * 16);
4149         }
4150         wr_reg16(info, SCR, val);
4151
4152         slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4153
4154         if (info->params.loopback)
4155                 enable_loopback(info);
4156 }
4157
4158 static void sync_mode(struct slgt_info *info)
4159 {
4160         unsigned short val;
4161
4162         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4163         tx_stop(info);
4164         rx_stop(info);
4165
4166         /* TCR (tx control)
4167          *
4168          * 15..13  mode
4169          *         000=HDLC/SDLC
4170          *         001=raw bit synchronous
4171          *         010=asynchronous/isochronous
4172          *         011=monosync byte synchronous
4173          *         100=bisync byte synchronous
4174          *         101=xsync byte synchronous
4175          * 12..10  encoding
4176          * 09      CRC enable
4177          * 08      CRC32
4178          * 07      1=RTS driver control
4179          * 06      preamble enable
4180          * 05..04  preamble length
4181          * 03      share open/close flag
4182          * 02      reset
4183          * 01      enable
4184          * 00      auto-CTS enable
4185          */
4186         val = BIT2;
4187
4188         switch(info->params.mode) {
4189         case MGSL_MODE_XSYNC:
4190                 val |= BIT15 + BIT13;
4191                 break;
4192         case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4193         case MGSL_MODE_BISYNC:   val |= BIT15; break;
4194         case MGSL_MODE_RAW:      val |= BIT13; break;
4195         }
4196         if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4197                 val |= BIT7;
4198
4199         switch(info->params.encoding)
4200         {
4201         case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4202         case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4203         case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4204         case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4205         case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4206         case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4207         case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4208         }
4209
4210         switch (info->params.crc_type & HDLC_CRC_MASK)
4211         {
4212         case HDLC_CRC_16_CCITT: val |= BIT9; break;
4213         case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4214         }
4215
4216         if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4217                 val |= BIT6;
4218
4219         switch (info->params.preamble_length)
4220         {
4221         case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4222         case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4223         case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4224         }
4225
4226         if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4227                 val |= BIT0;
4228
4229         wr_reg16(info, TCR, val);
4230
4231         /* TPR (transmit preamble) */
4232
4233         switch (info->params.preamble)
4234         {
4235         case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4236         case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4237         case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4238         case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4239         case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4240         default:                          val = 0x7e; break;
4241         }
4242         wr_reg8(info, TPR, (unsigned char)val);
4243
4244         /* RCR (rx control)
4245          *
4246          * 15..13  mode
4247          *         000=HDLC/SDLC
4248          *         001=raw bit synchronous
4249          *         010=asynchronous/isochronous
4250          *         011=monosync byte synchronous
4251          *         100=bisync byte synchronous
4252          *         101=xsync byte synchronous
4253          * 12..10  encoding
4254          * 09      CRC enable
4255          * 08      CRC32
4256          * 07..03  reserved, must be 0
4257          * 02      reset
4258          * 01      enable
4259          * 00      auto-DCD enable
4260          */
4261         val = 0;
4262
4263         switch(info->params.mode) {
4264         case MGSL_MODE_XSYNC:
4265                 val |= BIT15 + BIT13;
4266                 break;
4267         case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4268         case MGSL_MODE_BISYNC:   val |= BIT15; break;
4269         case MGSL_MODE_RAW:      val |= BIT13; break;
4270         }
4271
4272         switch(info->params.encoding)
4273         {
4274         case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4275         case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4276         case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4277         case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4278         case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4279         case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4280         case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4281         }
4282
4283         switch (info->params.crc_type & HDLC_CRC_MASK)
4284         {
4285         case HDLC_CRC_16_CCITT: val |= BIT9; break;
4286         case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4287         }
4288
4289         if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4290                 val |= BIT0;
4291
4292         wr_reg16(info, RCR, val);
4293
4294         /* CCR (clock control)
4295          *
4296          * 07..05  tx clock source
4297          * 04..02  rx clock source
4298          * 01      auxclk enable
4299          * 00      BRG enable
4300          */
4301         val = 0;
4302
4303         if (info->params.flags & HDLC_FLAG_TXC_BRG)
4304         {
4305                 // when RxC source is DPLL, BRG generates 16X DPLL
4306                 // reference clock, so take TxC from BRG/16 to get
4307                 // transmit clock at actual data rate
4308                 if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4309                         val |= BIT6 + BIT5;     /* 011, txclk = BRG/16 */
4310                 else
4311                         val |= BIT6;    /* 010, txclk = BRG */
4312         }
4313         else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4314                 val |= BIT7;    /* 100, txclk = DPLL Input */
4315         else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4316                 val |= BIT5;    /* 001, txclk = RXC Input */
4317
4318         if (info->params.flags & HDLC_FLAG_RXC_BRG)
4319                 val |= BIT3;    /* 010, rxclk = BRG */
4320         else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4321                 val |= BIT4;    /* 100, rxclk = DPLL */
4322         else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4323                 val |= BIT2;    /* 001, rxclk = TXC Input */
4324
4325         if (info->params.clock_speed)
4326                 val |= BIT1 + BIT0;
4327
4328         wr_reg8(info, CCR, (unsigned char)val);
4329
4330         if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4331         {
4332                 // program DPLL mode
4333                 switch(info->params.encoding)
4334                 {
4335                 case HDLC_ENCODING_BIPHASE_MARK:
4336                 case HDLC_ENCODING_BIPHASE_SPACE:
4337                         val = BIT7; break;
4338                 case HDLC_ENCODING_BIPHASE_LEVEL:
4339                 case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4340                         val = BIT7 + BIT6; break;
4341                 default: val = BIT6;    // NRZ encodings
4342                 }
4343                 wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4344
4345                 // DPLL requires a 16X reference clock from BRG
4346                 set_rate(info, info->params.clock_speed * 16);
4347         }
4348         else
4349                 set_rate(info, info->params.clock_speed);
4350
4351         tx_set_idle(info);
4352
4353         msc_set_vcr(info);
4354
4355         /* SCR (serial control)
4356          *
4357          * 15  1=tx req on FIFO half empty
4358          * 14  1=rx req on FIFO half full
4359          * 13  tx data  IRQ enable
4360          * 12  tx idle  IRQ enable
4361          * 11  underrun IRQ enable
4362          * 10  rx data  IRQ enable
4363          * 09  rx idle  IRQ enable
4364          * 08  overrun  IRQ enable
4365          * 07  DSR      IRQ enable
4366          * 06  CTS      IRQ enable
4367          * 05  DCD      IRQ enable
4368          * 04  RI       IRQ enable
4369          * 03  reserved, must be zero
4370          * 02  1=txd->rxd internal loopback enable
4371          * 01  reserved, must be zero
4372          * 00  1=master IRQ enable
4373          */
4374         wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4375
4376         if (info->params.loopback)
4377                 enable_loopback(info);
4378 }
4379
4380 /*
4381  *  set transmit idle mode
4382  */
4383 static void tx_set_idle(struct slgt_info *info)
4384 {
4385         unsigned char val;
4386         unsigned short tcr;
4387
4388         /* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4389          * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4390          */
4391         tcr = rd_reg16(info, TCR);
4392         if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4393                 /* disable preamble, set idle size to 16 bits */
4394                 tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4395                 /* MSB of 16 bit idle specified in tx preamble register (TPR) */
4396                 wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4397         } else if (!(tcr & BIT6)) {
4398                 /* preamble is disabled, set idle size to 8 bits */
4399                 tcr &= ~(BIT5 + BIT4);
4400         }
4401         wr_reg16(info, TCR, tcr);
4402
4403         if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4404                 /* LSB of custom tx idle specified in tx idle register */
4405                 val = (unsigned char)(info->idle_mode & 0xff);
4406         } else {
4407                 /* standard 8 bit idle patterns */
4408                 switch(info->idle_mode)
4409                 {
4410                 case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4411                 case HDLC_TXIDLE_ALT_ZEROS_ONES:
4412                 case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4413                 case HDLC_TXIDLE_ZEROS:
4414                 case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4415                 default:                         val = 0xff;
4416                 }
4417         }
4418
4419         wr_reg8(info, TIR, val);
4420 }
4421
4422 /*
4423  * get state of V24 status (input) signals
4424  */
4425 static void get_gtsignals(struct slgt_info *info)
4426 {
4427         unsigned short status = rd_reg16(info, SSR);
4428
4429         /* clear all serial signals except RTS and DTR */
4430         info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4431
4432         if (status & BIT3)
4433                 info->signals |= SerialSignal_DSR;
4434         if (status & BIT2)
4435                 info->signals |= SerialSignal_CTS;
4436         if (status & BIT1)
4437                 info->signals |= SerialSignal_DCD;
4438         if (status & BIT0)
4439                 info->signals |= SerialSignal_RI;
4440 }
4441
4442 /*
4443  * set V.24 Control Register based on current configuration
4444  */
4445 static void msc_set_vcr(struct slgt_info *info)
4446 {
4447         unsigned char val = 0;
4448
4449         /* VCR (V.24 control)
4450          *
4451          * 07..04  serial IF select
4452          * 03      DTR
4453          * 02      RTS
4454          * 01      LL
4455          * 00      RL
4456          */
4457
4458         switch(info->if_mode & MGSL_INTERFACE_MASK)
4459         {
4460         case MGSL_INTERFACE_RS232:
4461                 val |= BIT5; /* 0010 */
4462                 break;
4463         case MGSL_INTERFACE_V35:
4464                 val |= BIT7 + BIT6 + BIT5; /* 1110 */
4465                 break;
4466         case MGSL_INTERFACE_RS422:
4467                 val |= BIT6; /* 0100 */
4468                 break;
4469         }
4470
4471         if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4472                 val |= BIT4;
4473         if (info->signals & SerialSignal_DTR)
4474                 val |= BIT3;
4475         if (info->signals & SerialSignal_RTS)
4476                 val |= BIT2;
4477         if (info->if_mode & MGSL_INTERFACE_LL)
4478                 val |= BIT1;
4479         if (info->if_mode & MGSL_INTERFACE_RL)
4480                 val |= BIT0;
4481         wr_reg8(info, VCR, val);
4482 }
4483
4484 /*
4485  * set state of V24 control (output) signals
4486  */
4487 static void set_gtsignals(struct slgt_info *info)
4488 {
4489         unsigned char val = rd_reg8(info, VCR);
4490         if (info->signals & SerialSignal_DTR)
4491                 val |= BIT3;
4492         else
4493                 val &= ~BIT3;
4494         if (info->signals & SerialSignal_RTS)
4495                 val |= BIT2;
4496         else
4497                 val &= ~BIT2;
4498         wr_reg8(info, VCR, val);
4499 }
4500
4501 /*
4502  * free range of receive DMA buffers (i to last)
4503  */
4504 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4505 {
4506         int done = 0;
4507
4508         while(!done) {
4509                 /* reset current buffer for reuse */
4510                 info->rbufs[i].status = 0;
4511                 set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4512                 if (i == last)
4513                         done = 1;
4514                 if (++i == info->rbuf_count)
4515                         i = 0;
4516         }
4517         info->rbuf_current = i;
4518 }
4519
4520 /*
4521  * mark all receive DMA buffers as free
4522  */
4523 static void reset_rbufs(struct slgt_info *info)
4524 {
4525         free_rbufs(info, 0, info->rbuf_count - 1);
4526         info->rbuf_fill_index = 0;
4527         info->rbuf_fill_count = 0;
4528 }
4529
4530 /*
4531  * pass receive HDLC frame to upper layer
4532  *
4533  * return true if frame available, otherwise false
4534  */
4535 static bool rx_get_frame(struct slgt_info *info)
4536 {
4537         unsigned int start, end;
4538         unsigned short status;
4539         unsigned int framesize = 0;
4540         unsigned long flags;
4541         struct tty_struct *tty = info->port.tty;
4542         unsigned char addr_field = 0xff;
4543         unsigned int crc_size = 0;
4544
4545         switch (info->params.crc_type & HDLC_CRC_MASK) {
4546         case HDLC_CRC_16_CCITT: crc_size = 2; break;
4547         case HDLC_CRC_32_CCITT: crc_size = 4; break;
4548         }
4549
4550 check_again:
4551
4552         framesize = 0;
4553         addr_field = 0xff;
4554         start = end = info->rbuf_current;
4555
4556         for (;;) {
4557                 if (!desc_complete(info->rbufs[end]))
4558                         goto cleanup;
4559
4560                 if (framesize == 0 && info->params.addr_filter != 0xff)
4561                         addr_field = info->rbufs[end].buf[0];
4562
4563                 framesize += desc_count(info->rbufs[end]);
4564
4565                 if (desc_eof(info->rbufs[end]))
4566                         break;
4567
4568                 if (++end == info->rbuf_count)
4569                         end = 0;
4570
4571                 if (end == info->rbuf_current) {
4572                         if (info->rx_enabled){
4573                                 spin_lock_irqsave(&info->lock,flags);
4574                                 rx_start(info);
4575                                 spin_unlock_irqrestore(&info->lock,flags);
4576                         }
4577                         goto cleanup;
4578                 }
4579         }
4580
4581         /* status
4582          *
4583          * 15      buffer complete
4584          * 14..06  reserved
4585          * 05..04  residue
4586          * 02      eof (end of frame)
4587          * 01      CRC error
4588          * 00      abort
4589          */
4590         status = desc_status(info->rbufs[end]);
4591
4592         /* ignore CRC bit if not using CRC (bit is undefined) */
4593         if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4594                 status &= ~BIT1;
4595
4596         if (framesize == 0 ||
4597                  (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4598                 free_rbufs(info, start, end);
4599                 goto check_again;
4600         }
4601
4602         if (framesize < (2 + crc_size) || status & BIT0) {
4603                 info->icount.rxshort++;
4604                 framesize = 0;
4605         } else if (status & BIT1) {
4606                 info->icount.rxcrc++;
4607                 if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4608                         framesize = 0;
4609         }
4610
4611 #if SYNCLINK_GENERIC_HDLC
4612         if (framesize == 0) {
4613                 info->netdev->stats.rx_errors++;
4614                 info->netdev->stats.rx_frame_errors++;
4615         }
4616 #endif
4617
4618         DBGBH(("%s rx frame status=%04X size=%d\n",
4619                 info->device_name, status, framesize));
4620         DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4621
4622         if (framesize) {
4623                 if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4624                         framesize -= crc_size;
4625                         crc_size = 0;
4626                 }
4627
4628                 if (framesize > info->max_frame_size + crc_size)
4629                         info->icount.rxlong++;
4630                 else {
4631                         /* copy dma buffer(s) to contiguous temp buffer */
4632                         int copy_count = framesize;
4633                         int i = start;
4634                         unsigned char *p = info->tmp_rbuf;
4635                         info->tmp_rbuf_count = framesize;
4636
4637                         info->icount.rxok++;
4638
4639                         while(copy_count) {
4640                                 int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4641                                 memcpy(p, info->rbufs[i].buf, partial_count);
4642                                 p += partial_count;
4643                                 copy_count -= partial_count;
4644                                 if (++i == info->rbuf_count)
4645                                         i = 0;
4646                         }
4647
4648                         if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4649                                 *p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4650                                 framesize++;
4651                         }
4652
4653 #if SYNCLINK_GENERIC_HDLC
4654                         if (info->netcount)
4655                                 hdlcdev_rx(info,info->tmp_rbuf, framesize);
4656                         else
4657 #endif
4658                                 ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4659                 }
4660         }
4661         free_rbufs(info, start, end);
4662         return true;
4663
4664 cleanup:
4665         return false;
4666 }
4667
4668 /*
4669  * pass receive buffer (RAW synchronous mode) to tty layer
4670  * return true if buffer available, otherwise false
4671  */
4672 static bool rx_get_buf(struct slgt_info *info)
4673 {
4674         unsigned int i = info->rbuf_current;
4675         unsigned int count;
4676
4677         if (!desc_complete(info->rbufs[i]))
4678                 return false;
4679         count = desc_count(info->rbufs[i]);
4680         switch(info->params.mode) {
4681         case MGSL_MODE_MONOSYNC:
4682         case MGSL_MODE_BISYNC:
4683         case MGSL_MODE_XSYNC:
4684                 /* ignore residue in byte synchronous modes */
4685                 if (desc_residue(info->rbufs[i]))
4686                         count--;
4687                 break;
4688         }
4689         DBGDATA(info, info->rbufs[i].buf, count, "rx");
4690         DBGINFO(("rx_get_buf size=%d\n", count));
4691         if (count)
4692                 ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4693                                   info->flag_buf, count);
4694         free_rbufs(info, i, i);
4695         return true;
4696 }
4697
4698 static void reset_tbufs(struct slgt_info *info)
4699 {
4700         unsigned int i;
4701         info->tbuf_current = 0;
4702         for (i=0 ; i < info->tbuf_count ; i++) {
4703                 info->tbufs[i].status = 0;
4704                 info->tbufs[i].count  = 0;
4705         }
4706 }
4707
4708 /*
4709  * return number of free transmit DMA buffers
4710  */
4711 static unsigned int free_tbuf_count(struct slgt_info *info)
4712 {
4713         unsigned int count = 0;
4714         unsigned int i = info->tbuf_current;
4715
4716         do
4717         {
4718                 if (desc_count(info->tbufs[i]))
4719                         break; /* buffer in use */
4720                 ++count;
4721                 if (++i == info->tbuf_count)
4722                         i=0;
4723         } while (i != info->tbuf_current);
4724
4725         /* if tx DMA active, last zero count buffer is in use */
4726         if (count && (rd_reg32(info, TDCSR) & BIT0))
4727                 --count;
4728
4729         return count;
4730 }
4731
4732 /*
4733  * return number of bytes in unsent transmit DMA buffers
4734  * and the serial controller tx FIFO
4735  */
4736 static unsigned int tbuf_bytes(struct slgt_info *info)
4737 {
4738         unsigned int total_count = 0;
4739         unsigned int i = info->tbuf_current;
4740         unsigned int reg_value;
4741         unsigned int count;
4742         unsigned int active_buf_count = 0;
4743
4744         /*
4745          * Add descriptor counts for all tx DMA buffers.
4746          * If count is zero (cleared by DMA controller after read),
4747          * the buffer is complete or is actively being read from.
4748          *
4749          * Record buf_count of last buffer with zero count starting
4750          * from current ring position. buf_count is mirror
4751          * copy of count and is not cleared by serial controller.
4752          * If DMA controller is active, that buffer is actively
4753          * being read so add to total.
4754          */
4755         do {
4756                 count = desc_count(info->tbufs[i]);
4757                 if (count)
4758                         total_count += count;
4759                 else if (!total_count)
4760                         active_buf_count = info->tbufs[i].buf_count;
4761                 if (++i == info->tbuf_count)
4762                         i = 0;
4763         } while (i != info->tbuf_current);
4764
4765         /* read tx DMA status register */
4766         reg_value = rd_reg32(info, TDCSR);
4767
4768         /* if tx DMA active, last zero count buffer is in use */
4769         if (reg_value & BIT0)
4770                 total_count += active_buf_count;
4771
4772         /* add tx FIFO count = reg_value[15..8] */
4773         total_count += (reg_value >> 8) & 0xff;
4774
4775         /* if transmitter active add one byte for shift register */
4776         if (info->tx_active)
4777                 total_count++;
4778
4779         return total_count;
4780 }
4781
4782 /*
4783  * load data into transmit DMA buffer ring and start transmitter if needed
4784  * return true if data accepted, otherwise false (buffers full)
4785  */
4786 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4787 {
4788         unsigned short count;
4789         unsigned int i;
4790         struct slgt_desc *d;
4791
4792         /* check required buffer space */
4793         if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4794                 return false;
4795
4796         DBGDATA(info, buf, size, "tx");
4797
4798         /*
4799          * copy data to one or more DMA buffers in circular ring
4800          * tbuf_start   = first buffer for this data
4801          * tbuf_current = next free buffer
4802          *
4803          * Copy all data before making data visible to DMA controller by
4804          * setting descriptor count of the first buffer.
4805          * This prevents an active DMA controller from reading the first DMA
4806          * buffers of a frame and stopping before the final buffers are filled.
4807          */
4808
4809         info->tbuf_start = i = info->tbuf_current;
4810
4811         while (size) {
4812                 d = &info->tbufs[i];
4813
4814                 count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4815                 memcpy(d->buf, buf, count);
4816
4817                 size -= count;
4818                 buf  += count;
4819
4820                 /*
4821                  * set EOF bit for last buffer of HDLC frame or
4822                  * for every buffer in raw mode
4823                  */
4824                 if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4825                     info->params.mode == MGSL_MODE_RAW)
4826                         set_desc_eof(*d, 1);
4827                 else
4828                         set_desc_eof(*d, 0);
4829
4830                 /* set descriptor count for all but first buffer */
4831                 if (i != info->tbuf_start)
4832                         set_desc_count(*d, count);
4833                 d->buf_count = count;
4834
4835                 if (++i == info->tbuf_count)
4836                         i = 0;
4837         }
4838
4839         info->tbuf_current = i;
4840
4841         /* set first buffer count to make new data visible to DMA controller */
4842         d = &info->tbufs[info->tbuf_start];
4843         set_desc_count(*d, d->buf_count);
4844
4845         /* start transmitter if needed and update transmit timeout */
4846         if (!info->tx_active)
4847                 tx_start(info);
4848         update_tx_timer(info);
4849
4850         return true;
4851 }
4852
4853 static int register_test(struct slgt_info *info)
4854 {
4855         static unsigned short patterns[] =
4856                 {0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4857         static unsigned int count = ARRAY_SIZE(patterns);
4858         unsigned int i;
4859         int rc = 0;
4860
4861         for (i=0 ; i < count ; i++) {
4862                 wr_reg16(info, TIR, patterns[i]);
4863                 wr_reg16(info, BDR, patterns[(i+1)%count]);
4864                 if ((rd_reg16(info, TIR) != patterns[i]) ||
4865                     (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4866                         rc = -ENODEV;
4867                         break;
4868                 }
4869         }
4870         info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4871         info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4872         return rc;
4873 }
4874
4875 static int irq_test(struct slgt_info *info)
4876 {
4877         unsigned long timeout;
4878         unsigned long flags;
4879         struct tty_struct *oldtty = info->port.tty;
4880         u32 speed = info->params.data_rate;
4881
4882         info->params.data_rate = 921600;
4883         info->port.tty = NULL;
4884
4885         spin_lock_irqsave(&info->lock, flags);
4886         async_mode(info);
4887         slgt_irq_on(info, IRQ_TXIDLE);
4888
4889         /* enable transmitter */
4890         wr_reg16(info, TCR,
4891                 (unsigned short)(rd_reg16(info, TCR) | BIT1));
4892
4893         /* write one byte and wait for tx idle */
4894         wr_reg16(info, TDR, 0);
4895
4896         /* assume failure */
4897         info->init_error = DiagStatus_IrqFailure;
4898         info->irq_occurred = false;
4899
4900         spin_unlock_irqrestore(&info->lock, flags);
4901
4902         timeout=100;
4903         while(timeout-- && !info->irq_occurred)
4904                 msleep_interruptible(10);
4905
4906         spin_lock_irqsave(&info->lock,flags);
4907         reset_port(info);
4908         spin_unlock_irqrestore(&info->lock,flags);
4909
4910         info->params.data_rate = speed;
4911         info->port.tty = oldtty;
4912
4913         info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4914         return info->irq_occurred ? 0 : -ENODEV;
4915 }
4916
4917 static int loopback_test_rx(struct slgt_info *info)
4918 {
4919         unsigned char *src, *dest;
4920         int count;
4921
4922         if (desc_complete(info->rbufs[0])) {
4923                 count = desc_count(info->rbufs[0]);
4924                 src   = info->rbufs[0].buf;
4925                 dest  = info->tmp_rbuf;
4926
4927                 for( ; count ; count-=2, src+=2) {
4928                         /* src=data byte (src+1)=status byte */
4929                         if (!(*(src+1) & (BIT9 + BIT8))) {
4930                                 *dest = *src;
4931                                 dest++;
4932                                 info->tmp_rbuf_count++;
4933                         }
4934                 }
4935                 DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
4936                 return 1;
4937         }
4938         return 0;
4939 }
4940
4941 static int loopback_test(struct slgt_info *info)
4942 {
4943 #define TESTFRAMESIZE 20
4944
4945         unsigned long timeout;
4946         u16 count;
4947         unsigned char buf[TESTFRAMESIZE];
4948         int rc = -ENODEV;
4949         unsigned long flags;
4950
4951         struct tty_struct *oldtty = info->port.tty;
4952         MGSL_PARAMS params;
4953
4954         memcpy(&params, &info->params, sizeof(params));
4955
4956         info->params.mode = MGSL_MODE_ASYNC;
4957         info->params.data_rate = 921600;
4958         info->params.loopback = 1;
4959         info->port.tty = NULL;
4960
4961         /* build and send transmit frame */
4962         for (count = 0; count < TESTFRAMESIZE; ++count)
4963                 buf[count] = (unsigned char)count;
4964
4965         info->tmp_rbuf_count = 0;
4966         memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
4967
4968         /* program hardware for HDLC and enabled receiver */
4969         spin_lock_irqsave(&info->lock,flags);
4970         async_mode(info);
4971         rx_start(info);
4972         tx_load(info, buf, count);
4973         spin_unlock_irqrestore(&info->lock, flags);
4974
4975         /* wait for receive complete */
4976         for (timeout = 100; timeout; --timeout) {
4977                 msleep_interruptible(10);
4978                 if (loopback_test_rx(info)) {
4979                         rc = 0;
4980                         break;
4981                 }
4982         }
4983
4984         /* verify received frame length and contents */
4985         if (!rc && (info->tmp_rbuf_count != count ||
4986                   memcmp(buf, info->tmp_rbuf, count))) {
4987                 rc = -ENODEV;
4988         }
4989
4990         spin_lock_irqsave(&info->lock,flags);
4991         reset_adapter(info);
4992         spin_unlock_irqrestore(&info->lock,flags);
4993
4994         memcpy(&info->params, &params, sizeof(info->params));
4995         info->port.tty = oldtty;
4996
4997         info->init_error = rc ? DiagStatus_DmaFailure : 0;
4998         return rc;
4999 }
5000
5001 static int adapter_test(struct slgt_info *info)
5002 {
5003         DBGINFO(("testing %s\n", info->device_name));
5004         if (register_test(info) < 0) {
5005                 printk("register test failure %s addr=%08X\n",
5006                         info->device_name, info->phys_reg_addr);
5007         } else if (irq_test(info) < 0) {
5008                 printk("IRQ test failure %s IRQ=%d\n",
5009                         info->device_name, info->irq_level);
5010         } else if (loopback_test(info) < 0) {
5011                 printk("loopback test failure %s\n", info->device_name);
5012         }
5013         return info->init_error;
5014 }
5015
5016 /*
5017  * transmit timeout handler
5018  */
5019 static void tx_timeout(struct timer_list *t)
5020 {
5021         struct slgt_info *info = from_timer(info, t, tx_timer);
5022         unsigned long flags;
5023
5024         DBGINFO(("%s tx_timeout\n", info->device_name));
5025         if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5026                 info->icount.txtimeout++;
5027         }
5028         spin_lock_irqsave(&info->lock,flags);
5029         tx_stop(info);
5030         spin_unlock_irqrestore(&info->lock,flags);
5031
5032 #if SYNCLINK_GENERIC_HDLC
5033         if (info->netcount)
5034                 hdlcdev_tx_done(info);
5035         else
5036 #endif
5037                 bh_transmit(info);
5038 }
5039
5040 /*
5041  * receive buffer polling timer
5042  */
5043 static void rx_timeout(struct timer_list *t)
5044 {
5045         struct slgt_info *info = from_timer(info, t, rx_timer);
5046         unsigned long flags;
5047
5048         DBGINFO(("%s rx_timeout\n", info->device_name));
5049         spin_lock_irqsave(&info->lock, flags);
5050         info->pending_bh |= BH_RECEIVE;
5051         spin_unlock_irqrestore(&info->lock, flags);
5052         bh_handler(&info->task);
5053 }
5054