i2c: mxc: add CONFIG_CLK support
[platform/kernel/u-boot.git] / drivers / i2c / omap24xx_i2c.c
1 /*
2  * Basic I2C functions
3  *
4  * Copyright (c) 2004 Texas Instruments
5  *
6  * This package is free software;  you can redistribute it and/or
7  * modify it under the terms of the license found in the file
8  * named COPYING that should have accompanied this file.
9  *
10  * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
11  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
12  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
13  *
14  * Author: Jian Zhang jzhang@ti.com, Texas Instruments
15  *
16  * Copyright (c) 2003 Wolfgang Denk, wd@denx.de
17  * Rewritten to fit into the current U-Boot framework
18  *
19  * Adapted for OMAP2420 I2C, r-woodruff2@ti.com
20  *
21  * Copyright (c) 2013 Lubomir Popov <lpopov@mm-sol.com>, MM Solutions
22  * New i2c_read, i2c_write and i2c_probe functions, tested on OMAP4
23  * (4430/60/70), OMAP5 (5430) and AM335X (3359); should work on older
24  * OMAPs and derivatives as well. The only anticipated exception would
25  * be the OMAP2420, which shall require driver modification.
26  * - Rewritten i2c_read to operate correctly with all types of chips
27  *   (old function could not read consistent data from some I2C slaves).
28  * - Optimized i2c_write.
29  * - New i2c_probe, performs write access vs read. The old probe could
30  *   hang the system under certain conditions (e.g. unconfigured pads).
31  * - The read/write/probe functions try to identify unconfigured bus.
32  * - Status functions now read irqstatus_raw as per TRM guidelines
33  *   (except for OMAP243X and OMAP34XX).
34  * - Driver now supports up to I2C5 (OMAP5).
35  *
36  * Copyright (c) 2014 Hannes Schmelzer <oe5hpm@oevsv.at>, B&R
37  * - Added support for set_speed
38  *
39  */
40
41 #include <common.h>
42 #include <dm.h>
43 #include <i2c.h>
44
45 #include <asm/io.h>
46 #include <asm/omap_i2c.h>
47
48 /*
49  * Provide access to architecture-specific I2C header files for platforms
50  * that are NOT yet solely relying on CONFIG_DM_I2C, CONFIG_OF_CONTROL, and
51  * the defaults provided in 'omap24xx_i2c.h' for all U-Boot stages where I2C
52  * access is desired.
53  */
54 #ifndef CONFIG_ARCH_K3
55 #include <asm/arch/i2c.h>
56 #endif
57
58 #include "omap24xx_i2c.h"
59
60 #define I2C_TIMEOUT     1000
61
62 /* Absolutely safe for status update at 100 kHz I2C: */
63 #define I2C_WAIT        200
64
65 enum {
66         OMAP_I2C_REV_REG = 0,           /* Only on IP V1 (OMAP34XX) */
67         OMAP_I2C_IE_REG,                /* Only on IP V1 (OMAP34XX) */
68         OMAP_I2C_STAT_REG,
69         OMAP_I2C_WE_REG,
70         OMAP_I2C_SYSS_REG,
71         OMAP_I2C_BUF_REG,
72         OMAP_I2C_CNT_REG,
73         OMAP_I2C_DATA_REG,
74         OMAP_I2C_SYSC_REG,
75         OMAP_I2C_CON_REG,
76         OMAP_I2C_OA_REG,
77         OMAP_I2C_SA_REG,
78         OMAP_I2C_PSC_REG,
79         OMAP_I2C_SCLL_REG,
80         OMAP_I2C_SCLH_REG,
81         OMAP_I2C_SYSTEST_REG,
82         OMAP_I2C_BUFSTAT_REG,
83         /* Only on IP V2 (OMAP4430, etc.) */
84         OMAP_I2C_IP_V2_REVNB_LO,
85         OMAP_I2C_IP_V2_REVNB_HI,
86         OMAP_I2C_IP_V2_IRQSTATUS_RAW,
87         OMAP_I2C_IP_V2_IRQENABLE_SET,
88         OMAP_I2C_IP_V2_IRQENABLE_CLR,
89 };
90
91 static const u8 __maybe_unused reg_map_ip_v1[] = {
92         [OMAP_I2C_REV_REG] = 0x00,
93         [OMAP_I2C_IE_REG] = 0x04,
94         [OMAP_I2C_STAT_REG] = 0x08,
95         [OMAP_I2C_WE_REG] = 0x0c,
96         [OMAP_I2C_SYSS_REG] = 0x10,
97         [OMAP_I2C_BUF_REG] = 0x14,
98         [OMAP_I2C_CNT_REG] = 0x18,
99         [OMAP_I2C_DATA_REG] = 0x1c,
100         [OMAP_I2C_SYSC_REG] = 0x20,
101         [OMAP_I2C_CON_REG] = 0x24,
102         [OMAP_I2C_OA_REG] = 0x28,
103         [OMAP_I2C_SA_REG] = 0x2c,
104         [OMAP_I2C_PSC_REG] = 0x30,
105         [OMAP_I2C_SCLL_REG] = 0x34,
106         [OMAP_I2C_SCLH_REG] = 0x38,
107         [OMAP_I2C_SYSTEST_REG] = 0x3c,
108         [OMAP_I2C_BUFSTAT_REG] = 0x40,
109 };
110
111 static const u8 __maybe_unused reg_map_ip_v2[] = {
112         [OMAP_I2C_STAT_REG] = 0x28,
113         [OMAP_I2C_WE_REG] = 0x34,
114         [OMAP_I2C_SYSS_REG] = 0x90,
115         [OMAP_I2C_BUF_REG] = 0x94,
116         [OMAP_I2C_CNT_REG] = 0x98,
117         [OMAP_I2C_DATA_REG] = 0x9c,
118         [OMAP_I2C_SYSC_REG] = 0x10,
119         [OMAP_I2C_CON_REG] = 0xa4,
120         [OMAP_I2C_OA_REG] = 0xa8,
121         [OMAP_I2C_SA_REG] = 0xac,
122         [OMAP_I2C_PSC_REG] = 0xb0,
123         [OMAP_I2C_SCLL_REG] = 0xb4,
124         [OMAP_I2C_SCLH_REG] = 0xb8,
125         [OMAP_I2C_SYSTEST_REG] = 0xbc,
126         [OMAP_I2C_BUFSTAT_REG] = 0xc0,
127         [OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
128         [OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
129         [OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
130         [OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
131         [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
132 };
133
134 struct omap_i2c {
135         struct udevice *clk;
136         int ip_rev;
137         struct i2c *regs;
138         unsigned int speed;
139         int waitdelay;
140         int clk_id;
141 };
142
143 static inline const u8 *omap_i2c_get_ip_reg_map(int ip_rev)
144 {
145         switch (ip_rev) {
146         case OMAP_I2C_REV_V1:
147                 return reg_map_ip_v1;
148         case OMAP_I2C_REV_V2:
149                 /* Fall through... */
150         default:
151                 return reg_map_ip_v2;
152         }
153 }
154
155 static inline void omap_i2c_write_reg(void __iomem *base, int ip_rev,
156                                       u16 val, int reg)
157 {
158         writew(val, base + omap_i2c_get_ip_reg_map(ip_rev)[reg]);
159 }
160
161 static inline u16 omap_i2c_read_reg(void __iomem *base, int ip_rev, int reg)
162 {
163         return readw(base + omap_i2c_get_ip_reg_map(ip_rev)[reg]);
164 }
165
166 static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
167 {
168         unsigned long internal_clk = 0, fclk;
169         unsigned int prescaler;
170
171         /*
172          * This method is only called for Standard and Fast Mode speeds
173          *
174          * For some TI SoCs it is explicitly written in TRM (e,g, SPRUHZ6G,
175          * page 5685, Table 24-7)
176          * that the internal I2C clock (after prescaler) should be between
177          * 7-12 MHz (at least for Fast Mode (FS)).
178          *
179          * Such approach is used in v4.9 Linux kernel in:
180          * ./drivers/i2c/busses/i2c-omap.c (omap_i2c_init function).
181          */
182
183         speed /= 1000; /* convert speed to kHz */
184
185         if (speed > 100)
186                 internal_clk = 9600;
187         else
188                 internal_clk = 4000;
189
190         fclk = I2C_IP_CLK / 1000;
191         prescaler = fclk / internal_clk;
192         prescaler = prescaler - 1;
193
194         if (speed > 100) {
195                 unsigned long scl;
196
197                 /* Fast mode */
198                 scl = internal_clk / speed;
199                 *pscl = scl - (scl / 3) - I2C_FASTSPEED_SCLL_TRIM;
200                 *psch = (scl / 3) - I2C_FASTSPEED_SCLH_TRIM;
201         } else {
202                 /* Standard mode */
203                 *pscl = internal_clk / (speed * 2) - I2C_FASTSPEED_SCLL_TRIM;
204                 *psch = internal_clk / (speed * 2) - I2C_FASTSPEED_SCLH_TRIM;
205         }
206
207         debug("%s: speed [kHz]: %d psc: 0x%x sscl: 0x%x ssch: 0x%x\n",
208               __func__, speed, prescaler, *pscl, *psch);
209
210         if (*pscl <= 0 || *psch <= 0 || prescaler <= 0)
211                 return -EINVAL;
212
213         return prescaler;
214 }
215
216 /*
217  * Wait for the bus to be free by checking the Bus Busy (BB)
218  * bit to become clear
219  */
220 static int wait_for_bb(void __iomem *i2c_base, int ip_rev, int waitdelay)
221 {
222         int timeout = I2C_TIMEOUT;
223         int irq_stat_reg;
224         u16 stat;
225
226         irq_stat_reg = (ip_rev == OMAP_I2C_REV_V1) ?
227                        OMAP_I2C_STAT_REG : OMAP_I2C_IP_V2_IRQSTATUS_RAW;
228
229         /* clear current interrupts */
230         omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
231
232         while ((stat = omap_i2c_read_reg(i2c_base, ip_rev, irq_stat_reg) &
233                 I2C_STAT_BB) && timeout--) {
234                 omap_i2c_write_reg(i2c_base, ip_rev, stat, OMAP_I2C_STAT_REG);
235                 udelay(waitdelay);
236         }
237
238         if (timeout <= 0) {
239                 printf("Timed out in %s: status=%04x\n", __func__, stat);
240                 return 1;
241         }
242
243         /* clear delayed stuff */
244         omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
245         return 0;
246 }
247
248 /*
249  * Wait for the I2C controller to complete current action
250  * and update status
251  */
252 static u16 wait_for_event(void __iomem *i2c_base, int ip_rev, int waitdelay)
253 {
254         u16 status;
255         int timeout = I2C_TIMEOUT;
256         int irq_stat_reg;
257
258         irq_stat_reg = (ip_rev == OMAP_I2C_REV_V1) ?
259                        OMAP_I2C_STAT_REG : OMAP_I2C_IP_V2_IRQSTATUS_RAW;
260         do {
261                 udelay(waitdelay);
262                 status = omap_i2c_read_reg(i2c_base, ip_rev, irq_stat_reg);
263         } while (!(status &
264                    (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
265                     I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
266                     I2C_STAT_AL)) && timeout--);
267
268         if (timeout <= 0) {
269                 printf("Timed out in %s: status=%04x\n", __func__, status);
270                 /*
271                  * If status is still 0 here, probably the bus pads have
272                  * not been configured for I2C, and/or pull-ups are missing.
273                  */
274                 printf("Check if pads/pull-ups of bus are properly configured\n");
275                 omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
276                 status = 0;
277         }
278
279         return status;
280 }
281
282 static void flush_fifo(void __iomem *i2c_base, int ip_rev)
283 {
284         u16 stat;
285
286         /*
287          * note: if you try and read data when its not there or ready
288          * you get a bus error
289          */
290         while (1) {
291                 stat = omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_STAT_REG);
292                 if (stat == I2C_STAT_RRDY) {
293                         omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_DATA_REG);
294                         omap_i2c_write_reg(i2c_base, ip_rev,
295                                            I2C_STAT_RRDY, OMAP_I2C_STAT_REG);
296                         udelay(1000);
297                 } else
298                         break;
299         }
300 }
301
302 static int __omap24_i2c_setspeed(void __iomem *i2c_base, int ip_rev, uint speed,
303                                  int *waitdelay)
304 {
305         int psc, fsscll = 0, fssclh = 0;
306         int hsscll = 0, hssclh = 0;
307         u32 scll = 0, sclh = 0;
308
309         if (speed >= OMAP_I2C_HIGH_SPEED) {
310                 /* High speed */
311                 psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK;
312                 psc -= 1;
313                 if (psc < I2C_PSC_MIN) {
314                         printf("Error : I2C unsupported prescaler %d\n", psc);
315                         return -1;
316                 }
317
318                 /* For first phase of HS mode */
319                 fsscll = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
320
321                 fssclh = fsscll;
322
323                 fsscll -= I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM;
324                 fssclh -= I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM;
325                 if (((fsscll < 0) || (fssclh < 0)) ||
326                     ((fsscll > 255) || (fssclh > 255))) {
327                         puts("Error : I2C initializing first phase clock\n");
328                         return -1;
329                 }
330
331                 /* For second phase of HS mode */
332                 hsscll = hssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
333
334                 hsscll -= I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM;
335                 hssclh -= I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM;
336                 if (((fsscll < 0) || (fssclh < 0)) ||
337                     ((fsscll > 255) || (fssclh > 255))) {
338                         puts("Error : I2C initializing second phase clock\n");
339                         return -1;
340                 }
341
342                 scll = (unsigned int)hsscll << 8 | (unsigned int)fsscll;
343                 sclh = (unsigned int)hssclh << 8 | (unsigned int)fssclh;
344
345         } else {
346                 /* Standard and fast speed */
347                 psc = omap24_i2c_findpsc(&scll, &sclh, speed);
348                 if (0 > psc) {
349                         puts("Error : I2C initializing clock\n");
350                         return -1;
351                 }
352         }
353
354         /* wait for 20 clkperiods */
355         *waitdelay = (10000000 / speed) * 2;
356
357         omap_i2c_write_reg(i2c_base, ip_rev, 0,  OMAP_I2C_CON_REG);
358         omap_i2c_write_reg(i2c_base, ip_rev, psc, OMAP_I2C_PSC_REG);
359         omap_i2c_write_reg(i2c_base, ip_rev, scll, OMAP_I2C_SCLL_REG);
360         omap_i2c_write_reg(i2c_base, ip_rev, sclh, OMAP_I2C_SCLH_REG);
361         omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN, OMAP_I2C_CON_REG);
362
363         /* clear all pending status */
364         omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
365
366         return 0;
367 }
368
369 static void omap24_i2c_deblock(void __iomem *i2c_base, int ip_rev)
370 {
371         int i;
372         u16 systest;
373         u16 orgsystest;
374
375         /* set test mode ST_EN = 1 */
376         orgsystest = omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_SYSTEST_REG);
377         systest = orgsystest;
378
379         /* enable testmode */
380         systest |= I2C_SYSTEST_ST_EN;
381         omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
382         systest &= ~I2C_SYSTEST_TMODE_MASK;
383         systest |= 3 << I2C_SYSTEST_TMODE_SHIFT;
384         omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
385
386         /* set SCL, SDA  = 1 */
387         systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
388         omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
389         udelay(10);
390
391         /* toggle scl 9 clocks */
392         for (i = 0; i < 9; i++) {
393                 /* SCL = 0 */
394                 systest &= ~I2C_SYSTEST_SCL_O;
395                 omap_i2c_write_reg(i2c_base, ip_rev,
396                                    systest, OMAP_I2C_SYSTEST_REG);
397                 udelay(10);
398                 /* SCL = 1 */
399                 systest |= I2C_SYSTEST_SCL_O;
400                 omap_i2c_write_reg(i2c_base, ip_rev,
401                                    systest, OMAP_I2C_SYSTEST_REG);
402                 udelay(10);
403         }
404
405         /* send stop */
406         systest &= ~I2C_SYSTEST_SDA_O;
407         omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
408         udelay(10);
409         systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
410         omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
411         udelay(10);
412
413         /* restore original mode */
414         omap_i2c_write_reg(i2c_base, ip_rev, orgsystest, OMAP_I2C_SYSTEST_REG);
415 }
416
417 static void __omap24_i2c_init(void __iomem *i2c_base, int ip_rev, int speed,
418                               int slaveadd, int *waitdelay)
419 {
420         int timeout = I2C_TIMEOUT;
421         int deblock = 1;
422
423 retry:
424         if (omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_CON_REG) &
425             I2C_CON_EN) {
426                 omap_i2c_write_reg(i2c_base, ip_rev, 0, OMAP_I2C_CON_REG);
427                 udelay(50000);
428         }
429
430         /* for ES2 after soft reset */
431         omap_i2c_write_reg(i2c_base, ip_rev, 0x2, OMAP_I2C_SYSC_REG);
432         udelay(1000);
433
434         omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN, OMAP_I2C_CON_REG);
435         while (!(omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_SYSS_REG) &
436                  I2C_SYSS_RDONE) && timeout--) {
437                 if (timeout <= 0) {
438                         puts("ERROR: Timeout in soft-reset\n");
439                         return;
440                 }
441                 udelay(1000);
442         }
443
444         if (__omap24_i2c_setspeed(i2c_base, ip_rev, speed, waitdelay)) {
445                 printf("ERROR: failed to setup I2C bus-speed!\n");
446                 return;
447         }
448
449         /* own address */
450         omap_i2c_write_reg(i2c_base, ip_rev, slaveadd, OMAP_I2C_OA_REG);
451
452         if (ip_rev == OMAP_I2C_REV_V1) {
453                 /*
454                  * Have to enable interrupts for OMAP2/3, these IPs don't have
455                  * an 'irqstatus_raw' register and we shall have to poll 'stat'
456                  */
457                 omap_i2c_write_reg(i2c_base, ip_rev, I2C_IE_XRDY_IE |
458                                    I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
459                                    I2C_IE_NACK_IE | I2C_IE_AL_IE,
460                                    OMAP_I2C_IE_REG);
461         }
462
463         udelay(1000);
464         flush_fifo(i2c_base, ip_rev);
465         omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
466
467         /* Handle possible failed I2C state */
468         if (wait_for_bb(i2c_base, ip_rev, *waitdelay))
469                 if (deblock == 1) {
470                         omap24_i2c_deblock(i2c_base, ip_rev);
471                         deblock = 0;
472                         goto retry;
473                 }
474 }
475
476 /*
477  * i2c_probe: Use write access. Allows to identify addresses that are
478  *            write-only (like the config register of dual-port EEPROMs)
479  */
480 static int __omap24_i2c_probe(void __iomem *i2c_base, int ip_rev, int waitdelay,
481                               uchar chip)
482 {
483         u16 status;
484         int res = 1; /* default = fail */
485
486         if (chip == omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_OA_REG))
487                 return res;
488
489         /* Wait until bus is free */
490         if (wait_for_bb(i2c_base, ip_rev, waitdelay))
491                 return res;
492
493         /* No data transfer, slave addr only */
494         omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
495
496         /* Stop bit needed here */
497         omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
498                            I2C_CON_STT | I2C_CON_TRX | I2C_CON_STP,
499                            OMAP_I2C_CON_REG);
500
501         status = wait_for_event(i2c_base, ip_rev, waitdelay);
502
503         if ((status & ~I2C_STAT_XRDY) == 0 || (status & I2C_STAT_AL)) {
504                 /*
505                  * With current high-level command implementation, notifying
506                  * the user shall flood the console with 127 messages. If
507                  * silent exit is desired upon unconfigured bus, remove the
508                  * following 'if' section:
509                  */
510                 if (status == I2C_STAT_XRDY)
511                         printf("i2c_probe: pads on bus probably not configured (status=0x%x)\n",
512                                status);
513
514                 goto pr_exit;
515         }
516
517         /* Check for ACK (!NAK) */
518         if (!(status & I2C_STAT_NACK)) {
519                 res = 0;                                /* Device found */
520                 udelay(waitdelay);/* Required by AM335X in SPL */
521                 /* Abort transfer (force idle state) */
522                 omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_MST | I2C_CON_TRX,
523                                    OMAP_I2C_CON_REG);   /* Reset */
524                 udelay(1000);
525                 omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
526                                    I2C_CON_TRX | I2C_CON_STP,
527                                    OMAP_I2C_CON_REG);   /* STP */
528         }
529
530 pr_exit:
531         flush_fifo(i2c_base, ip_rev);
532         omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
533         return res;
534 }
535
536 /*
537  * i2c_read: Function now uses a single I2C read transaction with bulk transfer
538  *           of the requested number of bytes (note that the 'i2c md' command
539  *           limits this to 16 bytes anyway). If CONFIG_I2C_REPEATED_START is
540  *           defined in the board config header, this transaction shall be with
541  *           Repeated Start (Sr) between the address and data phases; otherwise
542  *           Stop-Start (P-S) shall be used (some I2C chips do require a P-S).
543  *           The address (reg offset) may be 0, 1 or 2 bytes long.
544  *           Function now reads correctly from chips that return more than one
545  *           byte of data per addressed register (like TI temperature sensors),
546  *           or that do not need a register address at all (such as some clock
547  *           distributors).
548  */
549 static int __omap24_i2c_read(void __iomem *i2c_base, int ip_rev, int waitdelay,
550                              uchar chip, uint addr, int alen, uchar *buffer,
551                              int len)
552 {
553         int i2c_error = 0;
554         u16 status;
555
556         if (alen < 0) {
557                 puts("I2C read: addr len < 0\n");
558                 return 1;
559         }
560
561         if (len < 0) {
562                 puts("I2C read: data len < 0\n");
563                 return 1;
564         }
565
566         if (buffer == NULL) {
567                 puts("I2C read: NULL pointer passed\n");
568                 return 1;
569         }
570
571         if (alen > 2) {
572                 printf("I2C read: addr len %d not supported\n", alen);
573                 return 1;
574         }
575
576         if (addr + len > (1 << 16)) {
577                 puts("I2C read: address out of range\n");
578                 return 1;
579         }
580
581 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
582         /*
583          * EEPROM chips that implement "address overflow" are ones
584          * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
585          * address and the extra bits end up in the "chip address"
586          * bit slots. This makes a 24WC08 (1Kbyte) chip look like
587          * four 256 byte chips.
588          *
589          * Note that we consider the length of the address field to
590          * still be one byte because the extra address bits are
591          * hidden in the chip address.
592          */
593         if (alen > 0)
594                 chip |= ((addr >> (alen * 8)) &
595                          CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
596 #endif
597
598         /* Wait until bus not busy */
599         if (wait_for_bb(i2c_base, ip_rev, waitdelay))
600                 return 1;
601
602         /* Zero, one or two bytes reg address (offset) */
603         omap_i2c_write_reg(i2c_base, ip_rev, alen, OMAP_I2C_CNT_REG);
604         /* Set slave address */
605         omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
606
607         if (alen) {
608                 /* Must write reg offset first */
609 #ifdef CONFIG_I2C_REPEATED_START
610                 /* No stop bit, use Repeated Start (Sr) */
611                 omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
612                                    I2C_CON_STT | I2C_CON_TRX, OMAP_I2C_CON_REG);
613 #else
614                 /* Stop - Start (P-S) */
615                 omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
616                                    I2C_CON_STT | I2C_CON_STP | I2C_CON_TRX,
617                                    OMAP_I2C_CON_REG);
618 #endif
619                 /* Send register offset */
620                 while (1) {
621                         status = wait_for_event(i2c_base, ip_rev, waitdelay);
622                         /* Try to identify bus that is not padconf'd for I2C */
623                         if (status == I2C_STAT_XRDY) {
624                                 i2c_error = 2;
625                                 printf("i2c_read (addr phase): pads on bus probably not configured (status=0x%x)\n",
626                                        status);
627                                 goto rd_exit;
628                         }
629                         if (status == 0 || (status & I2C_STAT_NACK)) {
630                                 i2c_error = 1;
631                                 printf("i2c_read: error waiting for addr ACK (status=0x%x)\n",
632                                        status);
633                                 goto rd_exit;
634                         }
635                         if (alen) {
636                                 if (status & I2C_STAT_XRDY) {
637                                         u8 addr_byte;
638                                         alen--;
639                                         addr_byte = (addr >> (8 * alen)) & 0xff;
640                                         omap_i2c_write_reg(i2c_base, ip_rev,
641                                                            addr_byte,
642                                                            OMAP_I2C_DATA_REG);
643                                         omap_i2c_write_reg(i2c_base, ip_rev,
644                                                            I2C_STAT_XRDY,
645                                                            OMAP_I2C_STAT_REG);
646                                 }
647                         }
648                         if (status & I2C_STAT_ARDY) {
649                                 omap_i2c_write_reg(i2c_base, ip_rev,
650                                                    I2C_STAT_ARDY,
651                                                    OMAP_I2C_STAT_REG);
652                                 break;
653                         }
654                 }
655         }
656
657         /* Set slave address */
658         omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
659         /* Read len bytes from slave */
660         omap_i2c_write_reg(i2c_base, ip_rev, len, OMAP_I2C_CNT_REG);
661         /* Need stop bit here */
662         omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
663                            I2C_CON_STT | I2C_CON_STP, OMAP_I2C_CON_REG);
664
665         /* Receive data */
666         while (1) {
667                 status = wait_for_event(i2c_base, ip_rev, waitdelay);
668                 /*
669                  * Try to identify bus that is not padconf'd for I2C. This
670                  * state could be left over from previous transactions if
671                  * the address phase is skipped due to alen=0.
672                  */
673                 if (status == I2C_STAT_XRDY) {
674                         i2c_error = 2;
675                         printf("i2c_read (data phase): pads on bus probably not configured (status=0x%x)\n",
676                                status);
677                         goto rd_exit;
678                 }
679                 if (status == 0 || (status & I2C_STAT_NACK)) {
680                         i2c_error = 1;
681                         goto rd_exit;
682                 }
683                 if (status & I2C_STAT_RRDY) {
684                         *buffer++ = omap_i2c_read_reg(i2c_base, ip_rev,
685                                                       OMAP_I2C_DATA_REG);
686                         omap_i2c_write_reg(i2c_base, ip_rev,
687                                            I2C_STAT_RRDY, OMAP_I2C_STAT_REG);
688                 }
689                 if (status & I2C_STAT_ARDY) {
690                         omap_i2c_write_reg(i2c_base, ip_rev,
691                                            I2C_STAT_ARDY, OMAP_I2C_STAT_REG);
692                         break;
693                 }
694         }
695
696 rd_exit:
697         flush_fifo(i2c_base, ip_rev);
698         omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
699         return i2c_error;
700 }
701
702 /* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */
703 static int __omap24_i2c_write(void __iomem *i2c_base, int ip_rev, int waitdelay,
704                               uchar chip, uint addr, int alen, uchar *buffer,
705                               int len)
706 {
707         int i;
708         u16 status;
709         int i2c_error = 0;
710         int timeout = I2C_TIMEOUT;
711
712         if (alen < 0) {
713                 puts("I2C write: addr len < 0\n");
714                 return 1;
715         }
716
717         if (len < 0) {
718                 puts("I2C write: data len < 0\n");
719                 return 1;
720         }
721
722         if (buffer == NULL) {
723                 puts("I2C write: NULL pointer passed\n");
724                 return 1;
725         }
726
727         if (alen > 2) {
728                 printf("I2C write: addr len %d not supported\n", alen);
729                 return 1;
730         }
731
732         if (addr + len > (1 << 16)) {
733                 printf("I2C write: address 0x%x + 0x%x out of range\n",
734                        addr, len);
735                 return 1;
736         }
737
738 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
739         /*
740          * EEPROM chips that implement "address overflow" are ones
741          * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
742          * address and the extra bits end up in the "chip address"
743          * bit slots. This makes a 24WC08 (1Kbyte) chip look like
744          * four 256 byte chips.
745          *
746          * Note that we consider the length of the address field to
747          * still be one byte because the extra address bits are
748          * hidden in the chip address.
749          */
750         if (alen > 0)
751                 chip |= ((addr >> (alen * 8)) &
752                          CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
753 #endif
754
755         /* Wait until bus not busy */
756         if (wait_for_bb(i2c_base, ip_rev, waitdelay))
757                 return 1;
758
759         /* Start address phase - will write regoffset + len bytes data */
760         omap_i2c_write_reg(i2c_base, ip_rev, alen + len, OMAP_I2C_CNT_REG);
761         /* Set slave address */
762         omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
763         /* Stop bit needed here */
764         omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
765                            I2C_CON_STT | I2C_CON_TRX | I2C_CON_STP,
766                            OMAP_I2C_CON_REG);
767
768         while (alen) {
769                 /* Must write reg offset (one or two bytes) */
770                 status = wait_for_event(i2c_base, ip_rev, waitdelay);
771                 /* Try to identify bus that is not padconf'd for I2C */
772                 if (status == I2C_STAT_XRDY) {
773                         i2c_error = 2;
774                         printf("i2c_write: pads on bus probably not configured (status=0x%x)\n",
775                                status);
776                         goto wr_exit;
777                 }
778                 if (status == 0 || (status & I2C_STAT_NACK)) {
779                         i2c_error = 1;
780                         printf("i2c_write: error waiting for addr ACK (status=0x%x)\n",
781                                status);
782                         goto wr_exit;
783                 }
784                 if (status & I2C_STAT_XRDY) {
785                         alen--;
786                         omap_i2c_write_reg(i2c_base, ip_rev,
787                                            (addr >> (8 * alen)) & 0xff,
788                                            OMAP_I2C_DATA_REG);
789                         omap_i2c_write_reg(i2c_base, ip_rev,
790                                            I2C_STAT_XRDY, OMAP_I2C_STAT_REG);
791                 } else {
792                         i2c_error = 1;
793                         printf("i2c_write: bus not ready for addr Tx (status=0x%x)\n",
794                                status);
795                         goto wr_exit;
796                 }
797         }
798
799         /* Address phase is over, now write data */
800         for (i = 0; i < len; i++) {
801                 status = wait_for_event(i2c_base, ip_rev, waitdelay);
802                 if (status == 0 || (status & I2C_STAT_NACK)) {
803                         i2c_error = 1;
804                         printf("i2c_write: error waiting for data ACK (status=0x%x)\n",
805                                status);
806                         goto wr_exit;
807                 }
808                 if (status & I2C_STAT_XRDY) {
809                         omap_i2c_write_reg(i2c_base, ip_rev,
810                                            buffer[i], OMAP_I2C_DATA_REG);
811                         omap_i2c_write_reg(i2c_base, ip_rev,
812                                            I2C_STAT_XRDY, OMAP_I2C_STAT_REG);
813                 } else {
814                         i2c_error = 1;
815                         printf("i2c_write: bus not ready for data Tx (i=%d)\n",
816                                i);
817                         goto wr_exit;
818                 }
819         }
820
821         /*
822          * poll ARDY bit for making sure that last byte really has been
823          * transferred on the bus.
824          */
825         do {
826                 status = wait_for_event(i2c_base, ip_rev, waitdelay);
827         } while (!(status & I2C_STAT_ARDY) && timeout--);
828         if (timeout <= 0)
829                 printf("i2c_write: timed out writig last byte!\n");
830
831 wr_exit:
832         flush_fifo(i2c_base, ip_rev);
833         omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
834         return i2c_error;
835 }
836
837 #ifndef CONFIG_DM_I2C
838 /*
839  * The legacy I2C functions. These need to get removed once
840  * all users of this driver are converted to DM.
841  */
842 static void __iomem *omap24_get_base(struct i2c_adapter *adap)
843 {
844         switch (adap->hwadapnr) {
845         case 0:
846                 return (void __iomem *)I2C_BASE1;
847                 break;
848         case 1:
849                 return (void __iomem *)I2C_BASE2;
850                 break;
851 #if (CONFIG_SYS_I2C_BUS_MAX > 2)
852         case 2:
853                 return (void __iomem *)I2C_BASE3;
854                 break;
855 #if (CONFIG_SYS_I2C_BUS_MAX > 3)
856         case 3:
857                 return (void __iomem *)I2C_BASE4;
858                 break;
859 #if (CONFIG_SYS_I2C_BUS_MAX > 4)
860         case 4:
861                 return (void __iomem *)I2C_BASE5;
862                 break;
863 #endif
864 #endif
865 #endif
866         default:
867                 printf("wrong hwadapnr: %d\n", adap->hwadapnr);
868                 break;
869         }
870
871         return NULL;
872 }
873
874 static int omap24_get_ip_rev(void)
875 {
876 #ifdef CONFIG_OMAP34XX
877         return OMAP_I2C_REV_V1;
878 #else
879         return OMAP_I2C_REV_V2;
880 #endif
881 }
882
883 static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
884                            int alen, uchar *buffer, int len)
885 {
886         void __iomem *i2c_base = omap24_get_base(adap);
887         int ip_rev = omap24_get_ip_rev();
888
889         return __omap24_i2c_read(i2c_base, ip_rev, adap->waitdelay, chip, addr,
890                                  alen, buffer, len);
891 }
892
893 static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
894                             int alen, uchar *buffer, int len)
895 {
896         void __iomem *i2c_base = omap24_get_base(adap);
897         int ip_rev = omap24_get_ip_rev();
898
899         return __omap24_i2c_write(i2c_base, ip_rev, adap->waitdelay, chip, addr,
900                                   alen, buffer, len);
901 }
902
903 static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
904 {
905         void __iomem *i2c_base = omap24_get_base(adap);
906         int ip_rev = omap24_get_ip_rev();
907         int ret;
908
909         ret = __omap24_i2c_setspeed(i2c_base, ip_rev, speed, &adap->waitdelay);
910         if (ret) {
911                 pr_err("%s: set i2c speed failed\n", __func__);
912                 return ret;
913         }
914
915         adap->speed = speed;
916
917         return 0;
918 }
919
920 static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
921 {
922         void __iomem *i2c_base = omap24_get_base(adap);
923         int ip_rev = omap24_get_ip_rev();
924
925         return __omap24_i2c_init(i2c_base, ip_rev, speed, slaveadd,
926                                  &adap->waitdelay);
927 }
928
929 static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
930 {
931         void __iomem *i2c_base = omap24_get_base(adap);
932         int ip_rev = omap24_get_ip_rev();
933
934         return __omap24_i2c_probe(i2c_base, ip_rev, adap->waitdelay, chip);
935 }
936
937 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED1)
938 #define CONFIG_SYS_OMAP24_I2C_SPEED1 CONFIG_SYS_OMAP24_I2C_SPEED
939 #endif
940 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE1)
941 #define CONFIG_SYS_OMAP24_I2C_SLAVE1 CONFIG_SYS_OMAP24_I2C_SLAVE
942 #endif
943
944 U_BOOT_I2C_ADAP_COMPLETE(omap24_0, omap24_i2c_init, omap24_i2c_probe,
945                          omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
946                          CONFIG_SYS_OMAP24_I2C_SPEED,
947                          CONFIG_SYS_OMAP24_I2C_SLAVE,
948                          0)
949 U_BOOT_I2C_ADAP_COMPLETE(omap24_1, omap24_i2c_init, omap24_i2c_probe,
950                          omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
951                          CONFIG_SYS_OMAP24_I2C_SPEED1,
952                          CONFIG_SYS_OMAP24_I2C_SLAVE1,
953                          1)
954
955 #if (CONFIG_SYS_I2C_BUS_MAX > 2)
956 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED2)
957 #define CONFIG_SYS_OMAP24_I2C_SPEED2 CONFIG_SYS_OMAP24_I2C_SPEED
958 #endif
959 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE2)
960 #define CONFIG_SYS_OMAP24_I2C_SLAVE2 CONFIG_SYS_OMAP24_I2C_SLAVE
961 #endif
962
963 U_BOOT_I2C_ADAP_COMPLETE(omap24_2, omap24_i2c_init, omap24_i2c_probe,
964                          omap24_i2c_read, omap24_i2c_write, NULL,
965                          CONFIG_SYS_OMAP24_I2C_SPEED2,
966                          CONFIG_SYS_OMAP24_I2C_SLAVE2,
967                          2)
968 #if (CONFIG_SYS_I2C_BUS_MAX > 3)
969 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED3)
970 #define CONFIG_SYS_OMAP24_I2C_SPEED3 CONFIG_SYS_OMAP24_I2C_SPEED
971 #endif
972 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE3)
973 #define CONFIG_SYS_OMAP24_I2C_SLAVE3 CONFIG_SYS_OMAP24_I2C_SLAVE
974 #endif
975
976 U_BOOT_I2C_ADAP_COMPLETE(omap24_3, omap24_i2c_init, omap24_i2c_probe,
977                          omap24_i2c_read, omap24_i2c_write, NULL,
978                          CONFIG_SYS_OMAP24_I2C_SPEED3,
979                          CONFIG_SYS_OMAP24_I2C_SLAVE3,
980                          3)
981 #if (CONFIG_SYS_I2C_BUS_MAX > 4)
982 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED4)
983 #define CONFIG_SYS_OMAP24_I2C_SPEED4 CONFIG_SYS_OMAP24_I2C_SPEED
984 #endif
985 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE4)
986 #define CONFIG_SYS_OMAP24_I2C_SLAVE4 CONFIG_SYS_OMAP24_I2C_SLAVE
987 #endif
988
989 U_BOOT_I2C_ADAP_COMPLETE(omap24_4, omap24_i2c_init, omap24_i2c_probe,
990                          omap24_i2c_read, omap24_i2c_write, NULL,
991                          CONFIG_SYS_OMAP24_I2C_SPEED4,
992                          CONFIG_SYS_OMAP24_I2C_SLAVE4,
993                          4)
994 #endif
995 #endif
996 #endif
997
998 #else /* CONFIG_DM_I2C */
999
1000 static int omap_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
1001 {
1002         struct omap_i2c *priv = dev_get_priv(bus);
1003         int ret;
1004
1005         debug("i2c_xfer: %d messages\n", nmsgs);
1006         for (; nmsgs > 0; nmsgs--, msg++) {
1007                 debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
1008                 if (msg->flags & I2C_M_RD) {
1009                         ret = __omap24_i2c_read(priv->regs, priv->ip_rev,
1010                                                 priv->waitdelay,
1011                                                 msg->addr, 0, 0, msg->buf,
1012                                                 msg->len);
1013                 } else {
1014                         ret = __omap24_i2c_write(priv->regs, priv->ip_rev,
1015                                                  priv->waitdelay,
1016                                                  msg->addr, 0, 0, msg->buf,
1017                                                  msg->len);
1018                 }
1019                 if (ret) {
1020                         debug("i2c_write: error sending\n");
1021                         return -EREMOTEIO;
1022                 }
1023         }
1024
1025         return 0;
1026 }
1027
1028 static int omap_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
1029 {
1030         struct omap_i2c *priv = dev_get_priv(bus);
1031
1032         priv->speed = speed;
1033
1034         return __omap24_i2c_setspeed(priv->regs, priv->ip_rev, speed,
1035                                      &priv->waitdelay);
1036 }
1037
1038 static int omap_i2c_probe_chip(struct udevice *bus, uint chip_addr,
1039                                      uint chip_flags)
1040 {
1041         struct omap_i2c *priv = dev_get_priv(bus);
1042
1043         return __omap24_i2c_probe(priv->regs, priv->ip_rev, priv->waitdelay,
1044                                   chip_addr);
1045 }
1046
1047 static int omap_i2c_probe(struct udevice *bus)
1048 {
1049         struct omap_i2c *priv = dev_get_priv(bus);
1050         struct omap_i2c_platdata *plat = dev_get_platdata(bus);
1051
1052         priv->speed = plat->speed;
1053         priv->regs = map_physmem(plat->base, sizeof(void *),
1054                                  MAP_NOCACHE);
1055         priv->ip_rev = plat->ip_rev;
1056
1057         __omap24_i2c_init(priv->regs, priv->ip_rev, priv->speed, 0,
1058                           &priv->waitdelay);
1059
1060         return 0;
1061 }
1062
1063 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
1064 static int omap_i2c_ofdata_to_platdata(struct udevice *bus)
1065 {
1066         struct omap_i2c_platdata *plat = dev_get_platdata(bus);
1067
1068         plat->base = devfdt_get_addr(bus);
1069         plat->speed = dev_read_u32_default(bus, "clock-frequency", 100000);
1070         plat->ip_rev = dev_get_driver_data(bus);
1071
1072         return 0;
1073 }
1074
1075 static const struct udevice_id omap_i2c_ids[] = {
1076         { .compatible = "ti,omap3-i2c", .data = OMAP_I2C_REV_V1 },
1077         { .compatible = "ti,omap4-i2c", .data = OMAP_I2C_REV_V2 },
1078         { }
1079 };
1080 #endif
1081
1082 static const struct dm_i2c_ops omap_i2c_ops = {
1083         .xfer           = omap_i2c_xfer,
1084         .probe_chip     = omap_i2c_probe_chip,
1085         .set_bus_speed  = omap_i2c_set_bus_speed,
1086 };
1087
1088 U_BOOT_DRIVER(i2c_omap) = {
1089         .name   = "i2c_omap",
1090         .id     = UCLASS_I2C,
1091 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
1092         .of_match = omap_i2c_ids,
1093         .ofdata_to_platdata = omap_i2c_ofdata_to_platdata,
1094         .platdata_auto_alloc_size = sizeof(struct omap_i2c_platdata),
1095 #endif
1096         .probe  = omap_i2c_probe,
1097         .priv_auto_alloc_size = sizeof(struct omap_i2c),
1098         .ops    = &omap_i2c_ops,
1099 #if !CONFIG_IS_ENABLED(OF_CONTROL)
1100         .flags  = DM_FLAG_PRE_RELOC,
1101 #endif
1102 };
1103
1104 #endif /* CONFIG_DM_I2C */