drivers/bluetooth/btuart_cs.c

   1 /*
   2  *
   3  *  Driver for Bluetooth PCMCIA cards with HCI UART interface
   4  *
   5  *  Copyright (C) 2001-2002  Marcel Holtmann <marcel@holtmann.org>
   6  *
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License version 2 as
  10  *  published by the Free Software Foundation;
  11  *
  12  *  Software distributed under the License is distributed on an "AS
  13  *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
  14  *  implied. See the License for the specific language governing
  15  *  rights and limitations under the License.
  16  *
  17  *  The initial developer of the original code is David A. Hinds
  18  *  <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
  19  *  are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
  20  *
  21  */
  22
  23 #include <linux/module.h>
  24
  25 #include <linux/kernel.h>
  26 #include <linux/init.h>
  27 #include <linux/slab.h>
  28 #include <linux/types.h>
  29 #include <linux/delay.h>
  30 #include <linux/errno.h>
  31 #include <linux/ptrace.h>
  32 #include <linux/ioport.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/moduleparam.h>
  35
  36 #include <linux/skbuff.h>
  37 #include <linux/string.h>
  38 #include <linux/serial.h>
  39 #include <linux/serial_reg.h>
  40 #include <linux/bitops.h>
  41 #include <asm/io.h>
  42
  43 #include <pcmcia/cistpl.h>
  44 #include <pcmcia/ciscode.h>
  45 #include <pcmcia/ds.h>
  46 #include <pcmcia/cisreg.h>
  47
  48 #include <net/bluetooth/bluetooth.h>
  49 #include <net/bluetooth/hci_core.h>
  50
  51
  52
  53 /* ======================== Module parameters ======================== */
  54
  55
  56 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
  57 MODULE_DESCRIPTION("Bluetooth driver for Bluetooth PCMCIA cards with HCI UART interface");
  58 MODULE_LICENSE("GPL");
  59
  60
  61
  62 /* ======================== Local structures ======================== */
  63
  64
  65 typedef struct btuart_info_t {
  66         struct pcmcia_device *p_dev;
  67
  68         struct hci_dev *hdev;
  69
  70         spinlock_t lock;        /* For serializing operations */
  71
  72         struct sk_buff_head txq;
  73         unsigned long tx_state;
  74
  75         unsigned long rx_state;
  76         unsigned long rx_count;
  77         struct sk_buff *rx_skb;
  78 } btuart_info_t;
  79
  80
  81 static int btuart_config(struct pcmcia_device *link);
  82 static void btuart_release(struct pcmcia_device *link);
  83
  84 static void btuart_detach(struct pcmcia_device *p_dev);
  85
  86
  87 /* Maximum baud rate */
  88 #define SPEED_MAX  115200
  89
  90 /* Default baud rate: 57600, 115200, 230400 or 460800 */
  91 #define DEFAULT_BAUD_RATE  115200
  92
  93
  94 /* Transmit states  */
  95 #define XMIT_SENDING    1
  96 #define XMIT_WAKEUP     2
  97 #define XMIT_WAITING    8
  98
  99 /* Receiver states */
 100 #define RECV_WAIT_PACKET_TYPE   0
 101 #define RECV_WAIT_EVENT_HEADER  1
 102 #define RECV_WAIT_ACL_HEADER    2
 103 #define RECV_WAIT_SCO_HEADER    3
 104 #define RECV_WAIT_DATA          4
 105
 106
 107
 108 /* ======================== Interrupt handling ======================== */
 109
 110
 111 static int btuart_write(unsigned int iobase, int fifo_size, __u8 *buf, int len)
 112 {
 113         int actual = 0;
 114
 115         /* Tx FIFO should be empty */
 116         if (!(inb(iobase + UART_LSR) & UART_LSR_THRE))
 117                 return 0;
 118
 119         /* Fill FIFO with current frame */
 120         while ((fifo_size-- > 0) && (actual < len)) {
 121                 /* Transmit next byte */
 122                 outb(buf[actual], iobase + UART_TX);
 123                 actual++;
 124         }
 125
 126         return actual;
 127 }
 128
 129
 130 static void btuart_write_wakeup(btuart_info_t *info)
 131 {
 132         if (!info) {
 133                 BT_ERR("Unknown device");
 134                 return;
 135         }
 136
 137         if (test_and_set_bit(XMIT_SENDING, &(info->tx_state))) {
 138                 set_bit(XMIT_WAKEUP, &(info->tx_state));
 139                 return;
 140         }
 141
 142         do {
 143                 unsigned int iobase = info->p_dev->resource[0]->start;
 144                 register struct sk_buff *skb;
 145                 int len;
 146
 147                 clear_bit(XMIT_WAKEUP, &(info->tx_state));
 148
 149                 if (!pcmcia_dev_present(info->p_dev))
 150                         return;
 151
 152                 skb = skb_dequeue(&(info->txq));
 153                 if (!skb)
 154                         break;
 155
 156                 /* Send frame */
 157                 len = btuart_write(iobase, 16, skb->data, skb->len);
 158                 set_bit(XMIT_WAKEUP, &(info->tx_state));
 159
 160                 if (len == skb->len) {
 161                         kfree_skb(skb);
 162                 } else {
 163                         skb_pull(skb, len);
 164                         skb_queue_head(&(info->txq), skb);
 165                 }
 166
 167                 info->hdev->stat.byte_tx += len;
 168
 169         } while (test_bit(XMIT_WAKEUP, &(info->tx_state)));
 170
 171         clear_bit(XMIT_SENDING, &(info->tx_state));
 172 }
 173
 174
 175 static void btuart_receive(btuart_info_t *info)
 176 {
 177         unsigned int iobase;
 178         int boguscount = 0;
 179
 180         if (!info) {
 181                 BT_ERR("Unknown device");
 182                 return;
 183         }
 184
 185         iobase = info->p_dev->resource[0]->start;
 186
 187         do {
 188                 info->hdev->stat.byte_rx++;
 189
 190                 /* Allocate packet */
 191                 if (info->rx_skb == NULL) {
 192                         info->rx_state = RECV_WAIT_PACKET_TYPE;
 193                         info->rx_count = 0;
 194                         info->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC);
 195                         if (!info->rx_skb) {
 196                                 BT_ERR("Can't allocate mem for new packet");
 197                                 return;
 198                         }
 199                 }
 200
 201                 if (info->rx_state == RECV_WAIT_PACKET_TYPE) {
 202
 203                         bt_cb(info->rx_skb)->pkt_type = inb(iobase + UART_RX);
 204
 205                         switch (bt_cb(info->rx_skb)->pkt_type) {
 206
 207                         case HCI_EVENT_PKT:
 208                                 info->rx_state = RECV_WAIT_EVENT_HEADER;
 209                                 info->rx_count = HCI_EVENT_HDR_SIZE;
 210                                 break;
 211
 212                         case HCI_ACLDATA_PKT:
 213                                 info->rx_state = RECV_WAIT_ACL_HEADER;
 214                                 info->rx_count = HCI_ACL_HDR_SIZE;
 215                                 break;
 216
 217                         case HCI_SCODATA_PKT:
 218                                 info->rx_state = RECV_WAIT_SCO_HEADER;
 219                                 info->rx_count = HCI_SCO_HDR_SIZE;
 220                                 break;
 221
 222                         default:
 223                                 /* Unknown packet */
 224                                 BT_ERR("Unknown HCI packet with type 0x%02x received", bt_cb(info->rx_skb)->pkt_type);
 225                                 info->hdev->stat.err_rx++;
 226                                 clear_bit(HCI_RUNNING, &(info->hdev->flags));
 227
 228                                 kfree_skb(info->rx_skb);
 229                                 info->rx_skb = NULL;
 230                                 break;
 231
 232                         }
 233
 234                 } else {
 235
 236                         *skb_put(info->rx_skb, 1) = inb(iobase + UART_RX);
 237                         info->rx_count--;
 238
 239                         if (info->rx_count == 0) {
 240
 241                                 int dlen;
 242                                 struct hci_event_hdr *eh;
 243                                 struct hci_acl_hdr *ah;
 244                                 struct hci_sco_hdr *sh;
 245
 246
 247                                 switch (info->rx_state) {
 248
 249                                 case RECV_WAIT_EVENT_HEADER:
 250                                         eh = hci_event_hdr(info->rx_skb);
 251                                         info->rx_state = RECV_WAIT_DATA;
 252                                         info->rx_count = eh->plen;
 253                                         break;
 254
 255                                 case RECV_WAIT_ACL_HEADER:
 256                                         ah = hci_acl_hdr(info->rx_skb);
 257                                         dlen = __le16_to_cpu(ah->dlen);
 258                                         info->rx_state = RECV_WAIT_DATA;
 259                                         info->rx_count = dlen;
 260                                         break;
 261
 262                                 case RECV_WAIT_SCO_HEADER:
 263                                         sh = hci_sco_hdr(info->rx_skb);
 264                                         info->rx_state = RECV_WAIT_DATA;
 265                                         info->rx_count = sh->dlen;
 266                                         break;
 267
 268                                 case RECV_WAIT_DATA:
 269                                         hci_recv_frame(info->hdev, info->rx_skb);
 270                                         info->rx_skb = NULL;
 271                                         break;
 272
 273                                 }
 274
 275                         }
 276
 277                 }
 278
 279                 /* Make sure we don't stay here too long */
 280                 if (boguscount++ > 16)
 281                         break;
 282
 283         } while (inb(iobase + UART_LSR) & UART_LSR_DR);
 284 }
 285
 286
 287 static irqreturn_t btuart_interrupt(int irq, void *dev_inst)
 288 {
 289         btuart_info_t *info = dev_inst;
 290         unsigned int iobase;
 291         int boguscount = 0;
 292         int iir, lsr;
 293         irqreturn_t r = IRQ_NONE;
 294
 295         if (!info || !info->hdev)
 296                 /* our irq handler is shared */
 297                 return IRQ_NONE;
 298
 299         iobase = info->p_dev->resource[0]->start;
 300
 301         spin_lock(&(info->lock));
 302
 303         iir = inb(iobase + UART_IIR) & UART_IIR_ID;
 304         while (iir) {
 305                 r = IRQ_HANDLED;
 306
 307                 /* Clear interrupt */
 308                 lsr = inb(iobase + UART_LSR);
 309
 310                 switch (iir) {
 311                 case UART_IIR_RLSI:
 312                         BT_ERR("RLSI");
 313                         break;
 314                 case UART_IIR_RDI:
 315                         /* Receive interrupt */
 316                         btuart_receive(info);
 317                         break;
 318                 case UART_IIR_THRI:
 319                         if (lsr & UART_LSR_THRE) {
 320                                 /* Transmitter ready for data */
 321                                 btuart_write_wakeup(info);
 322                         }
 323                         break;
 324                 default:
 325                         BT_ERR("Unhandled IIR=%#x", iir);
 326                         break;
 327                 }
 328
 329                 /* Make sure we don't stay here too long */
 330                 if (boguscount++ > 100)
 331                         break;
 332
 333                 iir = inb(iobase + UART_IIR) & UART_IIR_ID;
 334
 335         }
 336
 337         spin_unlock(&(info->lock));
 338
 339         return r;
 340 }
 341
 342
 343 static void btuart_change_speed(btuart_info_t *info, unsigned int speed)
 344 {
 345         unsigned long flags;
 346         unsigned int iobase;
 347         int fcr;                /* FIFO control reg */
 348         int lcr;                /* Line control reg */
 349         int divisor;
 350
 351         if (!info) {
 352                 BT_ERR("Unknown device");
 353                 return;
 354         }
 355
 356         iobase = info->p_dev->resource[0]->start;
 357
 358         spin_lock_irqsave(&(info->lock), flags);
 359
 360         /* Turn off interrupts */
 361         outb(0, iobase + UART_IER);
 362
 363         divisor = SPEED_MAX / speed;
 364
 365         fcr = UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
 366
 367         /*
 368          * Use trigger level 1 to avoid 3 ms. timeout delay at 9600 bps, and
 369          * almost 1,7 ms at 19200 bps. At speeds above that we can just forget
 370          * about this timeout since it will always be fast enough.
 371          */
 372
 373         if (speed < 38400)
 374                 fcr |= UART_FCR_TRIGGER_1;
 375         else
 376                 fcr |= UART_FCR_TRIGGER_14;
 377
 378         /* Bluetooth cards use 8N1 */
 379         lcr = UART_LCR_WLEN8;
 380
 381         outb(UART_LCR_DLAB | lcr, iobase + UART_LCR);   /* Set DLAB */
 382         outb(divisor & 0xff, iobase + UART_DLL);        /* Set speed */
 383         outb(divisor >> 8, iobase + UART_DLM);
 384         outb(lcr, iobase + UART_LCR);   /* Set 8N1  */
 385         outb(fcr, iobase + UART_FCR);   /* Enable FIFO's */
 386
 387         /* Turn on interrupts */
 388         outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
 389
 390         spin_unlock_irqrestore(&(info->lock), flags);
 391 }
 392
 393
 394
 395 /* ======================== HCI interface ======================== */
 396
 397
 398 static int btuart_hci_flush(struct hci_dev *hdev)
 399 {
 400         btuart_info_t *info = hci_get_drvdata(hdev);
 401
 402         /* Drop TX queue */
 403         skb_queue_purge(&(info->txq));
 404
 405         return 0;
 406 }
 407
 408
 409 static int btuart_hci_open(struct hci_dev *hdev)
 410 {
 411         set_bit(HCI_RUNNING, &(hdev->flags));
 412
 413         return 0;
 414 }
 415
 416
 417 static int btuart_hci_close(struct hci_dev *hdev)
 418 {
 419         if (!test_and_clear_bit(HCI_RUNNING, &(hdev->flags)))
 420                 return 0;
 421
 422         btuart_hci_flush(hdev);
 423
 424         return 0;
 425 }
 426
 427
 428 static int btuart_hci_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 429 {
 430         btuart_info_t *info = hci_get_drvdata(hdev);
 431
 432         switch (bt_cb(skb)->pkt_type) {
 433         case HCI_COMMAND_PKT:
 434                 hdev->stat.cmd_tx++;
 435                 break;
 436         case HCI_ACLDATA_PKT:
 437                 hdev->stat.acl_tx++;
 438                 break;
 439         case HCI_SCODATA_PKT:
 440                 hdev->stat.sco_tx++;
 441                 break;
 442         }
 443
 444         /* Prepend skb with frame type */
 445         memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
 446         skb_queue_tail(&(info->txq), skb);
 447
 448         btuart_write_wakeup(info);
 449
 450         return 0;
 451 }
 452
 453
 454
 455 /* ======================== Card services HCI interaction ======================== */
 456
 457
 458 static int btuart_open(btuart_info_t *info)
 459 {
 460         unsigned long flags;
 461         unsigned int iobase = info->p_dev->resource[0]->start;
 462         struct hci_dev *hdev;
 463
 464         spin_lock_init(&(info->lock));
 465
 466         skb_queue_head_init(&(info->txq));
 467
 468         info->rx_state = RECV_WAIT_PACKET_TYPE;
 469         info->rx_count = 0;
 470         info->rx_skb = NULL;
 471
 472         /* Initialize HCI device */
 473         hdev = hci_alloc_dev();
 474         if (!hdev) {
 475                 BT_ERR("Can't allocate HCI device");
 476                 return -ENOMEM;
 477         }
 478
 479         info->hdev = hdev;
 480
 481         hdev->bus = HCI_PCCARD;
 482         hci_set_drvdata(hdev, info);
 483         SET_HCIDEV_DEV(hdev, &info->p_dev->dev);
 484
 485         hdev->open  = btuart_hci_open;
 486         hdev->close = btuart_hci_close;
 487         hdev->flush = btuart_hci_flush;
 488         hdev->send  = btuart_hci_send_frame;
 489
 490         spin_lock_irqsave(&(info->lock), flags);
 491
 492         /* Reset UART */
 493         outb(0, iobase + UART_MCR);
 494
 495         /* Turn off interrupts */
 496         outb(0, iobase + UART_IER);
 497
 498         /* Initialize UART */
 499         outb(UART_LCR_WLEN8, iobase + UART_LCR);        /* Reset DLAB */
 500         outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase + UART_MCR);
 501
 502         /* Turn on interrupts */
 503         // outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
 504
 505         spin_unlock_irqrestore(&(info->lock), flags);
 506
 507         btuart_change_speed(info, DEFAULT_BAUD_RATE);
 508
 509         /* Timeout before it is safe to send the first HCI packet */
 510         msleep(1000);
 511
 512         /* Register HCI device */
 513         if (hci_register_dev(hdev) < 0) {
 514                 BT_ERR("Can't register HCI device");
 515                 info->hdev = NULL;
 516                 hci_free_dev(hdev);
 517                 return -ENODEV;
 518         }
 519
 520         return 0;
 521 }
 522
 523
 524 static int btuart_close(btuart_info_t *info)
 525 {
 526         unsigned long flags;
 527         unsigned int iobase = info->p_dev->resource[0]->start;
 528         struct hci_dev *hdev = info->hdev;
 529
 530         if (!hdev)
 531                 return -ENODEV;
 532
 533         btuart_hci_close(hdev);
 534
 535         spin_lock_irqsave(&(info->lock), flags);
 536
 537         /* Reset UART */
 538         outb(0, iobase + UART_MCR);
 539
 540         /* Turn off interrupts */
 541         outb(0, iobase + UART_IER);
 542
 543         spin_unlock_irqrestore(&(info->lock), flags);
 544
 545         hci_unregister_dev(hdev);
 546         hci_free_dev(hdev);
 547
 548         return 0;
 549 }
 550
 551 static int btuart_probe(struct pcmcia_device *link)
 552 {
 553         btuart_info_t *info;
 554
 555         /* Create new info device */
 556         info = devm_kzalloc(&link->dev, sizeof(*info), GFP_KERNEL);
 557         if (!info)
 558                 return -ENOMEM;
 559
 560         info->p_dev = link;
 561         link->priv = info;
 562
 563         link->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_SET_VPP |
 564                 CONF_AUTO_SET_IO;
 565
 566         return btuart_config(link);
 567 }
 568
 569
 570 static void btuart_detach(struct pcmcia_device *link)
 571 {
 572         btuart_release(link);
 573 }
 574
 575 static int btuart_check_config(struct pcmcia_device *p_dev, void *priv_data)
 576 {
 577         int *try = priv_data;
 578
 579         if (!try)
 580                 p_dev->io_lines = 16;
 581
 582         if ((p_dev->resource[0]->end != 8) || (p_dev->resource[0]->start == 0))
 583                 return -EINVAL;
 584
 585         p_dev->resource[0]->end = 8;
 586         p_dev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
 587         p_dev->resource[0]->flags |= IO_DATA_PATH_WIDTH_8;
 588
 589         return pcmcia_request_io(p_dev);
 590 }
 591
 592 static int btuart_check_config_notpicky(struct pcmcia_device *p_dev,
 593                                         void *priv_data)
 594 {
 595         static unsigned int base[5] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, 0x0 };
 596         int j;
 597
 598         if (p_dev->io_lines > 3)
 599                 return -ENODEV;
 600
 601         p_dev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
 602         p_dev->resource[0]->flags |= IO_DATA_PATH_WIDTH_8;
 603         p_dev->resource[0]->end = 8;
 604
 605         for (j = 0; j < 5; j++) {
 606                 p_dev->resource[0]->start = base[j];
 607                 p_dev->io_lines = base[j] ? 16 : 3;
 608                 if (!pcmcia_request_io(p_dev))
 609                         return 0;
 610         }
 611         return -ENODEV;
 612 }
 613
 614 static int btuart_config(struct pcmcia_device *link)
 615 {
 616         btuart_info_t *info = link->priv;
 617         int i;
 618         int try;
 619
 620         /* First pass: look for a config entry that looks normal.
 621            Two tries: without IO aliases, then with aliases */
 622         for (try = 0; try < 2; try++)
 623                 if (!pcmcia_loop_config(link, btuart_check_config, &try))
 624                         goto found_port;
 625
 626         /* Second pass: try to find an entry that isn't picky about
 627            its base address, then try to grab any standard serial port
 628            address, and finally try to get any free port. */
 629         if (!pcmcia_loop_config(link, btuart_check_config_notpicky, NULL))
 630                 goto found_port;
 631
 632         BT_ERR("No usable port range found");
 633         goto failed;
 634
 635 found_port:
 636         i = pcmcia_request_irq(link, btuart_interrupt);
 637         if (i != 0)
 638                 goto failed;
 639
 640         i = pcmcia_enable_device(link);
 641         if (i != 0)
 642                 goto failed;
 643
 644         if (btuart_open(info) != 0)
 645                 goto failed;
 646
 647         return 0;
 648
 649 failed:
 650         btuart_release(link);
 651         return -ENODEV;
 652 }
 653
 654
 655 static void btuart_release(struct pcmcia_device *link)
 656 {
 657         btuart_info_t *info = link->priv;
 658
 659         btuart_close(info);
 660
 661         pcmcia_disable_device(link);
 662 }
 663
 664 static const struct pcmcia_device_id btuart_ids[] = {
 665         /* don't use this driver. Use serial_cs + hci_uart instead */
 666         PCMCIA_DEVICE_NULL
 667 };
 668 MODULE_DEVICE_TABLE(pcmcia, btuart_ids);
 669
 670 static struct pcmcia_driver btuart_driver = {
 671         .owner          = THIS_MODULE,
 672         .name           = "btuart_cs",
 673         .probe          = btuart_probe,
 674         .remove         = btuart_detach,
 675         .id_table       = btuart_ids,
 676 };
 677 module_pcmcia_driver(btuart_driver);