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22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/i2c.h>
25#include <linux/init.h>
26#include <linux/time.h>
27#include <linux/sched.h>
28#include <linux/delay.h>
29#include <linux/errno.h>
30#include <linux/interrupt.h>
31#include <linux/i2c-pxa.h>
32#include <linux/of.h>
33#include <linux/of_device.h>
34#include <linux/platform_device.h>
35#include <linux/err.h>
36#include <linux/clk.h>
37#include <linux/slab.h>
38#include <linux/io.h>
39#include <linux/i2c/pxa-i2c.h>
40
41#include <asm/irq.h>
42
43struct pxa_reg_layout {
44 u32 ibmr;
45 u32 idbr;
46 u32 icr;
47 u32 isr;
48 u32 isar;
49};
50
51enum pxa_i2c_types {
52 REGS_PXA2XX,
53 REGS_PXA3XX,
54 REGS_CE4100,
55};
56
57
58
59
60static struct pxa_reg_layout pxa_reg_layout[] = {
61 [REGS_PXA2XX] = {
62 .ibmr = 0x00,
63 .idbr = 0x08,
64 .icr = 0x10,
65 .isr = 0x18,
66 .isar = 0x20,
67 },
68 [REGS_PXA3XX] = {
69 .ibmr = 0x00,
70 .idbr = 0x04,
71 .icr = 0x08,
72 .isr = 0x0c,
73 .isar = 0x10,
74 },
75 [REGS_CE4100] = {
76 .ibmr = 0x14,
77 .idbr = 0x0c,
78 .icr = 0x00,
79 .isr = 0x04,
80
81 },
82};
83
84static const struct platform_device_id i2c_pxa_id_table[] = {
85 { "pxa2xx-i2c", REGS_PXA2XX },
86 { "pxa3xx-pwri2c", REGS_PXA3XX },
87 { "ce4100-i2c", REGS_CE4100 },
88 { },
89};
90MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
91
92
93
94
95
96#define ICR_START (1 << 0)
97#define ICR_STOP (1 << 1)
98#define ICR_ACKNAK (1 << 2)
99#define ICR_TB (1 << 3)
100#define ICR_MA (1 << 4)
101#define ICR_SCLE (1 << 5)
102#define ICR_IUE (1 << 6)
103#define ICR_GCD (1 << 7)
104#define ICR_ITEIE (1 << 8)
105#define ICR_IRFIE (1 << 9)
106#define ICR_BEIE (1 << 10)
107#define ICR_SSDIE (1 << 11)
108#define ICR_ALDIE (1 << 12)
109#define ICR_SADIE (1 << 13)
110#define ICR_UR (1 << 14)
111#define ICR_FM (1 << 15)
112#define ICR_HS (1 << 16)
113#define ICR_GPIOEN (1 << 19)
114
115#define ISR_RWM (1 << 0)
116#define ISR_ACKNAK (1 << 1)
117#define ISR_UB (1 << 2)
118#define ISR_IBB (1 << 3)
119#define ISR_SSD (1 << 4)
120#define ISR_ALD (1 << 5)
121#define ISR_ITE (1 << 6)
122#define ISR_IRF (1 << 7)
123#define ISR_GCAD (1 << 8)
124#define ISR_SAD (1 << 9)
125#define ISR_BED (1 << 10)
126
127struct pxa_i2c {
128 spinlock_t lock;
129 wait_queue_head_t wait;
130 struct i2c_msg *msg;
131 unsigned int msg_num;
132 unsigned int msg_idx;
133 unsigned int msg_ptr;
134 unsigned int slave_addr;
135 unsigned int req_slave_addr;
136
137 struct i2c_adapter adap;
138 struct clk *clk;
139#ifdef CONFIG_I2C_PXA_SLAVE
140 struct i2c_slave_client *slave;
141#endif
142
143 unsigned int irqlogidx;
144 u32 isrlog[32];
145 u32 icrlog[32];
146
147 void __iomem *reg_base;
148 void __iomem *reg_ibmr;
149 void __iomem *reg_idbr;
150 void __iomem *reg_icr;
151 void __iomem *reg_isr;
152 void __iomem *reg_isar;
153
154 unsigned long iobase;
155 unsigned long iosize;
156
157 int irq;
158 unsigned int use_pio :1;
159 unsigned int fast_mode :1;
160 unsigned int high_mode:1;
161 unsigned char master_code;
162 unsigned long rate;
163 bool highmode_enter;
164};
165
166#define _IBMR(i2c) ((i2c)->reg_ibmr)
167#define _IDBR(i2c) ((i2c)->reg_idbr)
168#define _ICR(i2c) ((i2c)->reg_icr)
169#define _ISR(i2c) ((i2c)->reg_isr)
170#define _ISAR(i2c) ((i2c)->reg_isar)
171
172
173
174
175#define I2C_PXA_SLAVE_ADDR 0x1
176
177#ifdef DEBUG
178
179struct bits {
180 u32 mask;
181 const char *set;
182 const char *unset;
183};
184#define PXA_BIT(m, s, u) { .mask = m, .set = s, .unset = u }
185
186static inline void
187decode_bits(const char *prefix, const struct bits *bits, int num, u32 val)
188{
189 printk("%s %08x: ", prefix, val);
190 while (num--) {
191 const char *str = val & bits->mask ? bits->set : bits->unset;
192 if (str)
193 printk("%s ", str);
194 bits++;
195 }
196}
197
198static const struct bits isr_bits[] = {
199 PXA_BIT(ISR_RWM, "RX", "TX"),
200 PXA_BIT(ISR_ACKNAK, "NAK", "ACK"),
201 PXA_BIT(ISR_UB, "Bsy", "Rdy"),
202 PXA_BIT(ISR_IBB, "BusBsy", "BusRdy"),
203 PXA_BIT(ISR_SSD, "SlaveStop", NULL),
204 PXA_BIT(ISR_ALD, "ALD", NULL),
205 PXA_BIT(ISR_ITE, "TxEmpty", NULL),
206 PXA_BIT(ISR_IRF, "RxFull", NULL),
207 PXA_BIT(ISR_GCAD, "GenCall", NULL),
208 PXA_BIT(ISR_SAD, "SlaveAddr", NULL),
209 PXA_BIT(ISR_BED, "BusErr", NULL),
210};
211
212static void decode_ISR(unsigned int val)
213{
214 decode_bits(KERN_DEBUG "ISR", isr_bits, ARRAY_SIZE(isr_bits), val);
215 printk("\n");
216}
217
218static const struct bits icr_bits[] = {
219 PXA_BIT(ICR_START, "START", NULL),
220 PXA_BIT(ICR_STOP, "STOP", NULL),
221 PXA_BIT(ICR_ACKNAK, "ACKNAK", NULL),
222 PXA_BIT(ICR_TB, "TB", NULL),
223 PXA_BIT(ICR_MA, "MA", NULL),
224 PXA_BIT(ICR_SCLE, "SCLE", "scle"),
225 PXA_BIT(ICR_IUE, "IUE", "iue"),
226 PXA_BIT(ICR_GCD, "GCD", NULL),
227 PXA_BIT(ICR_ITEIE, "ITEIE", NULL),
228 PXA_BIT(ICR_IRFIE, "IRFIE", NULL),
229 PXA_BIT(ICR_BEIE, "BEIE", NULL),
230 PXA_BIT(ICR_SSDIE, "SSDIE", NULL),
231 PXA_BIT(ICR_ALDIE, "ALDIE", NULL),
232 PXA_BIT(ICR_SADIE, "SADIE", NULL),
233 PXA_BIT(ICR_UR, "UR", "ur"),
234};
235
236#ifdef CONFIG_I2C_PXA_SLAVE
237static void decode_ICR(unsigned int val)
238{
239 decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val);
240 printk("\n");
241}
242#endif
243
244static unsigned int i2c_debug = DEBUG;
245
246static void i2c_pxa_show_state(struct pxa_i2c *i2c, int lno, const char *fname)
247{
248 dev_dbg(&i2c->adap.dev, "state:%s:%d: ISR=%08x, ICR=%08x, IBMR=%02x\n", fname, lno,
249 readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
250}
251
252#define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __func__)
253
254static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
255{
256 unsigned int i;
257 struct device *dev = &i2c->adap.dev;
258
259 dev_err(dev, "slave_0x%x error: %s\n",
260 i2c->req_slave_addr >> 1, why);
261 dev_err(dev, "msg_num: %d msg_idx: %d msg_ptr: %d\n",
262 i2c->msg_num, i2c->msg_idx, i2c->msg_ptr);
263 dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n",
264 readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)),
265 readl(_ISR(i2c)));
266 dev_dbg(dev, "log: ");
267 for (i = 0; i < i2c->irqlogidx; i++)
268 pr_debug("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
269
270 pr_debug("\n");
271}
272
273#else
274
275#define i2c_debug 0
276
277#define show_state(i2c) do { } while (0)
278#define decode_ISR(val) do { } while (0)
279#define decode_ICR(val) do { } while (0)
280#define i2c_pxa_scream_blue_murder(i2c, why) do { } while (0)
281
282#endif
283
284static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
285static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
286
287static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
288{
289 return !(readl(_ICR(i2c)) & ICR_SCLE);
290}
291
292static void i2c_pxa_abort(struct pxa_i2c *i2c)
293{
294 int i = 250;
295
296 if (i2c_pxa_is_slavemode(i2c)) {
297 dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__);
298 return;
299 }
300
301 while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
302 unsigned long icr = readl(_ICR(i2c));
303
304 icr &= ~ICR_START;
305 icr |= ICR_ACKNAK | ICR_STOP | ICR_TB;
306
307 writel(icr, _ICR(i2c));
308
309 show_state(i2c);
310
311 mdelay(1);
312 i --;
313 }
314
315 writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP),
316 _ICR(i2c));
317}
318
319static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c)
320{
321 int timeout = DEF_TIMEOUT;
322
323 while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
324 if ((readl(_ISR(i2c)) & ISR_SAD) != 0)
325 timeout += 4;
326
327 msleep(2);
328 show_state(i2c);
329 }
330
331 if (timeout < 0)
332 show_state(i2c);
333
334 return timeout < 0 ? I2C_RETRY : 0;
335}
336
337static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
338{
339 unsigned long timeout = jiffies + HZ*4;
340
341 while (time_before(jiffies, timeout)) {
342 if (i2c_debug > 1)
343 dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
344 __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
345
346 if (readl(_ISR(i2c)) & ISR_SAD) {
347 if (i2c_debug > 0)
348 dev_dbg(&i2c->adap.dev, "%s: Slave detected\n", __func__);
349 goto out;
350 }
351
352
353
354
355
356 if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 && readl(_IBMR(i2c)) == 3) {
357 if (i2c_debug > 0)
358 dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
359 return 1;
360 }
361
362 msleep(1);
363 }
364
365 if (i2c_debug > 0)
366 dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
367 out:
368 return 0;
369}
370
371static int i2c_pxa_set_master(struct pxa_i2c *i2c)
372{
373 if (i2c_debug)
374 dev_dbg(&i2c->adap.dev, "setting to bus master\n");
375
376 if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) != 0) {
377 dev_dbg(&i2c->adap.dev, "%s: unit is busy\n", __func__);
378 if (!i2c_pxa_wait_master(i2c)) {
379 dev_dbg(&i2c->adap.dev, "%s: error: unit busy\n", __func__);
380 return I2C_RETRY;
381 }
382 }
383
384 writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
385 return 0;
386}
387
388#ifdef CONFIG_I2C_PXA_SLAVE
389static int i2c_pxa_wait_slave(struct pxa_i2c *i2c)
390{
391 unsigned long timeout = jiffies + HZ*1;
392
393
394
395 show_state(i2c);
396
397 while (time_before(jiffies, timeout)) {
398 if (i2c_debug > 1)
399 dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
400 __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
401
402 if ((readl(_ISR(i2c)) & (ISR_UB|ISR_IBB)) == 0 ||
403 (readl(_ISR(i2c)) & ISR_SAD) != 0 ||
404 (readl(_ICR(i2c)) & ICR_SCLE) == 0) {
405 if (i2c_debug > 1)
406 dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
407 return 1;
408 }
409
410 msleep(1);
411 }
412
413 if (i2c_debug > 0)
414 dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
415 return 0;
416}
417
418
419
420
421
422static void i2c_pxa_set_slave(struct pxa_i2c *i2c, int errcode)
423{
424 show_state(i2c);
425
426 if (errcode < 0) {
427 udelay(100);
428 } else {
429
430
431
432 if (readl(_ICR(i2c)) & ICR_STOP) {
433 udelay(100);
434 writel(readl(_ICR(i2c)) & ~ICR_STOP, _ICR(i2c));
435 }
436
437 if (!i2c_pxa_wait_slave(i2c)) {
438 dev_err(&i2c->adap.dev, "%s: wait timedout\n",
439 __func__);
440 return;
441 }
442 }
443
444 writel(readl(_ICR(i2c)) & ~(ICR_STOP|ICR_ACKNAK|ICR_MA), _ICR(i2c));
445 writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
446
447 if (i2c_debug) {
448 dev_dbg(&i2c->adap.dev, "ICR now %08x, ISR %08x\n", readl(_ICR(i2c)), readl(_ISR(i2c)));
449 decode_ICR(readl(_ICR(i2c)));
450 }
451}
452#else
453#define i2c_pxa_set_slave(i2c, err) do { } while (0)
454#endif
455
456static void i2c_pxa_reset(struct pxa_i2c *i2c)
457{
458 pr_debug("Resetting I2C Controller Unit\n");
459
460
461 i2c_pxa_abort(i2c);
462
463
464 writel(ICR_UR, _ICR(i2c));
465 writel(I2C_ISR_INIT, _ISR(i2c));
466 writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
467
468 if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
469 writel(i2c->slave_addr, _ISAR(i2c));
470
471
472 writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
473 writel(readl(_ICR(i2c)) | (i2c->high_mode ? ICR_HS : 0), _ICR(i2c));
474
475#ifdef CONFIG_I2C_PXA_SLAVE
476 dev_info(&i2c->adap.dev, "Enabling slave mode\n");
477 writel(readl(_ICR(i2c)) | ICR_SADIE | ICR_ALDIE | ICR_SSDIE, _ICR(i2c));
478#endif
479
480 i2c_pxa_set_slave(i2c, 0);
481
482
483 writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
484 udelay(100);
485}
486
487
488#ifdef CONFIG_I2C_PXA_SLAVE
489
490
491
492
493static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
494{
495 if (isr & ISR_BED) {
496
497 } else {
498 int ret = 0;
499
500 if (i2c->slave != NULL)
501 ret = i2c->slave->read(i2c->slave->data);
502
503 writel(ret, _IDBR(i2c));
504 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
505 }
506}
507
508static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
509{
510 unsigned int byte = readl(_IDBR(i2c));
511
512 if (i2c->slave != NULL)
513 i2c->slave->write(i2c->slave->data, byte);
514
515 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
516}
517
518static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
519{
520 int timeout;
521
522 if (i2c_debug > 0)
523 dev_dbg(&i2c->adap.dev, "SAD, mode is slave-%cx\n",
524 (isr & ISR_RWM) ? 'r' : 't');
525
526 if (i2c->slave != NULL)
527 i2c->slave->event(i2c->slave->data,
528 (isr & ISR_RWM) ? I2C_SLAVE_EVENT_START_READ : I2C_SLAVE_EVENT_START_WRITE);
529
530
531
532
533
534
535 writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
536 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
537
538 timeout = 0x10000;
539
540 while (1) {
541 if ((readl(_IBMR(i2c)) & 2) == 2)
542 break;
543
544 timeout--;
545
546 if (timeout <= 0) {
547 dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
548 break;
549 }
550 }
551
552 writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
553}
554
555static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
556{
557 if (i2c_debug > 2)
558 dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop)\n");
559
560 if (i2c->slave != NULL)
561 i2c->slave->event(i2c->slave->data, I2C_SLAVE_EVENT_STOP);
562
563 if (i2c_debug > 2)
564 dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop) acked\n");
565
566
567
568
569
570 if (i2c->msg)
571 i2c_pxa_master_complete(i2c, I2C_RETRY);
572}
573#else
574static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
575{
576 if (isr & ISR_BED) {
577
578 } else {
579 writel(0, _IDBR(i2c));
580 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
581 }
582}
583
584static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
585{
586 writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
587}
588
589static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
590{
591 int timeout;
592
593
594
595
596
597
598 writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
599 writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
600
601 timeout = 0x10000;
602
603 while (1) {
604 if ((readl(_IBMR(i2c)) & 2) == 2)
605 break;
606
607 timeout--;
608
609 if (timeout <= 0) {
610 dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
611 break;
612 }
613 }
614
615 writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
616}
617
618static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
619{
620 if (i2c->msg)
621 i2c_pxa_master_complete(i2c, I2C_RETRY);
622}
623#endif
624
625
626
627
628
629static inline unsigned int i2c_pxa_addr_byte(struct i2c_msg *msg)
630{
631 unsigned int addr = (msg->addr & 0x7f) << 1;
632
633 if (msg->flags & I2C_M_RD)
634 addr |= 1;
635
636 return addr;
637}
638
639static inline void i2c_pxa_start_message(struct pxa_i2c *i2c)
640{
641 u32 icr;
642
643
644
645
646 writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
647 i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
648
649
650
651
652 icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
653 writel(icr | ICR_START | ICR_TB, _ICR(i2c));
654}
655
656static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
657{
658 u32 icr;
659
660
661
662
663 icr = readl(_ICR(i2c));
664 icr &= ~(ICR_STOP | ICR_ACKNAK);
665 writel(icr, _ICR(i2c));
666}
667
668static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
669{
670
671 long timeout = 2 * DEF_TIMEOUT;
672
673
674
675
676 while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
677 udelay(1000);
678 show_state(i2c);
679 }
680
681 if (timeout < 0) {
682 show_state(i2c);
683 dev_err(&i2c->adap.dev,
684 "i2c_pxa: timeout waiting for bus free\n");
685 return I2C_RETRY;
686 }
687
688
689
690
691 writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
692
693 return 0;
694}
695
696
697
698
699
700
701
702static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
703{
704 u32 icr;
705 long timeout;
706
707 spin_lock_irq(&i2c->lock);
708 i2c->highmode_enter = true;
709 writel(i2c->master_code, _IDBR(i2c));
710
711 icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
712 icr |= ICR_GPIOEN | ICR_START | ICR_TB | ICR_ITEIE;
713 writel(icr, _ICR(i2c));
714
715 spin_unlock_irq(&i2c->lock);
716 timeout = wait_event_timeout(i2c->wait,
717 i2c->highmode_enter == false, HZ * 1);
718
719 i2c->highmode_enter = false;
720
721 return (timeout == 0) ? I2C_RETRY : 0;
722}
723
724static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
725 struct i2c_msg *msg, int num)
726{
727 unsigned long timeout = 500000;
728 int ret = 0;
729
730 ret = i2c_pxa_pio_set_master(i2c);
731 if (ret)
732 goto out;
733
734 i2c->msg = msg;
735 i2c->msg_num = num;
736 i2c->msg_idx = 0;
737 i2c->msg_ptr = 0;
738 i2c->irqlogidx = 0;
739
740 i2c_pxa_start_message(i2c);
741
742 while (i2c->msg_num > 0 && --timeout) {
743 i2c_pxa_handler(0, i2c);
744 udelay(10);
745 }
746
747 i2c_pxa_stop_message(i2c);
748
749
750
751
752 ret = i2c->msg_idx;
753
754out:
755 if (timeout == 0) {
756 i2c_pxa_scream_blue_murder(i2c, "timeout");
757 ret = I2C_RETRY;
758 }
759
760 return ret;
761}
762
763
764
765
766static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
767{
768 long timeout;
769 int ret;
770
771
772
773
774 ret = i2c_pxa_wait_bus_not_busy(i2c);
775 if (ret) {
776 dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
777 goto out;
778 }
779
780
781
782
783 ret = i2c_pxa_set_master(i2c);
784 if (ret) {
785 dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
786 goto out;
787 }
788
789 if (i2c->high_mode) {
790 ret = i2c_pxa_send_mastercode(i2c);
791 if (ret) {
792 dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
793 goto out;
794 }
795 }
796
797 spin_lock_irq(&i2c->lock);
798
799 i2c->msg = msg;
800 i2c->msg_num = num;
801 i2c->msg_idx = 0;
802 i2c->msg_ptr = 0;
803 i2c->irqlogidx = 0;
804
805 i2c_pxa_start_message(i2c);
806
807 spin_unlock_irq(&i2c->lock);
808
809
810
811
812 timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
813 i2c_pxa_stop_message(i2c);
814
815
816
817
818 ret = i2c->msg_idx;
819
820 if (!timeout && i2c->msg_num) {
821 i2c_pxa_scream_blue_murder(i2c, "timeout");
822 ret = I2C_RETRY;
823 }
824
825 out:
826 return ret;
827}
828
829static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
830 struct i2c_msg msgs[], int num)
831{
832 struct pxa_i2c *i2c = adap->algo_data;
833 int ret, i;
834
835
836
837
838
839 if (!(readl(_ICR(i2c)) & ICR_IUE))
840 i2c_pxa_reset(i2c);
841
842 for (i = adap->retries; i >= 0; i--) {
843 ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
844 if (ret != I2C_RETRY)
845 goto out;
846
847 if (i2c_debug)
848 dev_dbg(&adap->dev, "Retrying transmission\n");
849 udelay(100);
850 }
851 i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
852 ret = -EREMOTEIO;
853 out:
854 i2c_pxa_set_slave(i2c, ret);
855 return ret;
856}
857
858
859
860
861static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret)
862{
863 i2c->msg_ptr = 0;
864 i2c->msg = NULL;
865 i2c->msg_idx ++;
866 i2c->msg_num = 0;
867 if (ret)
868 i2c->msg_idx = ret;
869 if (!i2c->use_pio)
870 wake_up(&i2c->wait);
871}
872
873static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
874{
875 u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
876
877 again:
878
879
880
881 if (isr & ISR_ALD) {
882
883
884
885
886 i2c_pxa_scream_blue_murder(i2c, "ALD set");
887
888
889
890
891
892
893
894 return;
895 }
896
897 if ((isr & ISR_BED) &&
898 (!((i2c->msg->flags & I2C_M_IGNORE_NAK) &&
899 (isr & ISR_ACKNAK)))) {
900 int ret = BUS_ERROR;
901
902
903
904
905
906
907 if (isr & ISR_ACKNAK) {
908 if (i2c->msg_ptr == 0 && i2c->msg_idx == 0)
909 ret = I2C_RETRY;
910 else
911 ret = XFER_NAKED;
912 }
913 i2c_pxa_master_complete(i2c, ret);
914 } else if (isr & ISR_RWM) {
915
916
917
918
919 if (i2c->msg_ptr == i2c->msg->len - 1 &&
920 i2c->msg_idx == i2c->msg_num - 1)
921 icr |= ICR_STOP | ICR_ACKNAK;
922
923 icr |= ICR_ALDIE | ICR_TB;
924 } else if (i2c->msg_ptr < i2c->msg->len) {
925
926
927
928 writel(i2c->msg->buf[i2c->msg_ptr++], _IDBR(i2c));
929
930 icr |= ICR_ALDIE | ICR_TB;
931
932
933
934
935
936 if ((i2c->msg_ptr == i2c->msg->len) &&
937 ((i2c->msg->flags & I2C_M_STOP) ||
938 (i2c->msg_idx == i2c->msg_num - 1)))
939 icr |= ICR_STOP;
940
941 } else if (i2c->msg_idx < i2c->msg_num - 1) {
942
943
944
945 i2c->msg_ptr = 0;
946 i2c->msg_idx ++;
947 i2c->msg++;
948
949
950
951
952
953
954 if (i2c->msg->flags & I2C_M_NOSTART)
955 goto again;
956
957
958
959
960 writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
961 i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
962
963
964
965
966 icr &= ~ICR_ALDIE;
967 icr |= ICR_START | ICR_TB;
968 } else {
969 if (i2c->msg->len == 0) {
970
971
972
973
974
975 i2c_pxa_reset(i2c);
976 }
977 i2c_pxa_master_complete(i2c, 0);
978 }
979
980 i2c->icrlog[i2c->irqlogidx-1] = icr;
981
982 writel(icr, _ICR(i2c));
983 show_state(i2c);
984}
985
986static void i2c_pxa_irq_rxfull(struct pxa_i2c *i2c, u32 isr)
987{
988 u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
989
990
991
992
993 i2c->msg->buf[i2c->msg_ptr++] = readl(_IDBR(i2c));
994
995 if (i2c->msg_ptr < i2c->msg->len) {
996
997
998
999
1000 if (i2c->msg_ptr == i2c->msg->len - 1)
1001 icr |= ICR_STOP | ICR_ACKNAK;
1002
1003 icr |= ICR_ALDIE | ICR_TB;
1004 } else {
1005 i2c_pxa_master_complete(i2c, 0);
1006 }
1007
1008 i2c->icrlog[i2c->irqlogidx-1] = icr;
1009
1010 writel(icr, _ICR(i2c));
1011}
1012
1013#define VALID_INT_SOURCE (ISR_SSD | ISR_ALD | ISR_ITE | ISR_IRF | \
1014 ISR_SAD | ISR_BED)
1015static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
1016{
1017 struct pxa_i2c *i2c = dev_id;
1018 u32 isr = readl(_ISR(i2c));
1019
1020 if (!(isr & VALID_INT_SOURCE))
1021 return IRQ_NONE;
1022
1023 if (i2c_debug > 2 && 0) {
1024 dev_dbg(&i2c->adap.dev, "%s: ISR=%08x, ICR=%08x, IBMR=%02x\n",
1025 __func__, isr, readl(_ICR(i2c)), readl(_IBMR(i2c)));
1026 decode_ISR(isr);
1027 }
1028
1029 if (i2c->irqlogidx < ARRAY_SIZE(i2c->isrlog))
1030 i2c->isrlog[i2c->irqlogidx++] = isr;
1031
1032 show_state(i2c);
1033
1034
1035
1036
1037 writel(isr & VALID_INT_SOURCE, _ISR(i2c));
1038
1039 if (isr & ISR_SAD)
1040 i2c_pxa_slave_start(i2c, isr);
1041 if (isr & ISR_SSD)
1042 i2c_pxa_slave_stop(i2c);
1043
1044 if (i2c_pxa_is_slavemode(i2c)) {
1045 if (isr & ISR_ITE)
1046 i2c_pxa_slave_txempty(i2c, isr);
1047 if (isr & ISR_IRF)
1048 i2c_pxa_slave_rxfull(i2c, isr);
1049 } else if (i2c->msg && (!i2c->highmode_enter)) {
1050 if (isr & ISR_ITE)
1051 i2c_pxa_irq_txempty(i2c, isr);
1052 if (isr & ISR_IRF)
1053 i2c_pxa_irq_rxfull(i2c, isr);
1054 } else if ((isr & ISR_ITE) && i2c->highmode_enter) {
1055 i2c->highmode_enter = false;
1056 wake_up(&i2c->wait);
1057 } else {
1058 i2c_pxa_scream_blue_murder(i2c, "spurious irq");
1059 }
1060
1061 return IRQ_HANDLED;
1062}
1063
1064
1065static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
1066{
1067 struct pxa_i2c *i2c = adap->algo_data;
1068 int ret, i;
1069
1070 for (i = adap->retries; i >= 0; i--) {
1071 ret = i2c_pxa_do_xfer(i2c, msgs, num);
1072 if (ret != I2C_RETRY)
1073 goto out;
1074
1075 if (i2c_debug)
1076 dev_dbg(&adap->dev, "Retrying transmission\n");
1077 udelay(100);
1078 }
1079 i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
1080 ret = -EREMOTEIO;
1081 out:
1082 i2c_pxa_set_slave(i2c, ret);
1083 return ret;
1084}
1085
1086static u32 i2c_pxa_functionality(struct i2c_adapter *adap)
1087{
1088 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
1089 I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
1090}
1091
1092static const struct i2c_algorithm i2c_pxa_algorithm = {
1093 .master_xfer = i2c_pxa_xfer,
1094 .functionality = i2c_pxa_functionality,
1095};
1096
1097static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
1098 .master_xfer = i2c_pxa_pio_xfer,
1099 .functionality = i2c_pxa_functionality,
1100};
1101
1102static const struct of_device_id i2c_pxa_dt_ids[] = {
1103 { .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
1104 { .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
1105 { .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA2XX },
1106 {}
1107};
1108MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
1109
1110static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
1111 enum pxa_i2c_types *i2c_types)
1112{
1113 struct device_node *np = pdev->dev.of_node;
1114 const struct of_device_id *of_id =
1115 of_match_device(i2c_pxa_dt_ids, &pdev->dev);
1116
1117 if (!of_id)
1118 return 1;
1119
1120
1121 i2c->adap.nr = -1;
1122
1123 if (of_get_property(np, "mrvl,i2c-polling", NULL))
1124 i2c->use_pio = 1;
1125 if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
1126 i2c->fast_mode = 1;
1127
1128 *i2c_types = (enum pxa_i2c_types)(of_id->data);
1129
1130 return 0;
1131}
1132
1133static int i2c_pxa_probe_pdata(struct platform_device *pdev,
1134 struct pxa_i2c *i2c,
1135 enum pxa_i2c_types *i2c_types)
1136{
1137 struct i2c_pxa_platform_data *plat = dev_get_platdata(&pdev->dev);
1138 const struct platform_device_id *id = platform_get_device_id(pdev);
1139
1140 *i2c_types = id->driver_data;
1141 if (plat) {
1142 i2c->use_pio = plat->use_pio;
1143 i2c->fast_mode = plat->fast_mode;
1144 i2c->high_mode = plat->high_mode;
1145 i2c->master_code = plat->master_code;
1146 if (!i2c->master_code)
1147 i2c->master_code = 0xe;
1148 i2c->rate = plat->rate;
1149 }
1150 return 0;
1151}
1152
1153static int i2c_pxa_probe(struct platform_device *dev)
1154{
1155 struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
1156 enum pxa_i2c_types i2c_type;
1157 struct pxa_i2c *i2c;
1158 struct resource *res = NULL;
1159 int ret, irq;
1160
1161 i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL);
1162 if (!i2c)
1163 return -ENOMEM;
1164
1165 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
1166 i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
1167 if (IS_ERR(i2c->reg_base))
1168 return PTR_ERR(i2c->reg_base);
1169
1170 irq = platform_get_irq(dev, 0);
1171 if (irq < 0) {
1172 dev_err(&dev->dev, "no irq resource: %d\n", irq);
1173 return irq;
1174 }
1175
1176
1177 i2c->adap.nr = dev->id;
1178
1179 ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
1180 if (ret > 0)
1181 ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
1182 if (ret < 0)
1183 return ret;
1184
1185 i2c->adap.owner = THIS_MODULE;
1186 i2c->adap.retries = 5;
1187
1188 spin_lock_init(&i2c->lock);
1189 init_waitqueue_head(&i2c->wait);
1190
1191 strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
1192
1193 i2c->clk = devm_clk_get(&dev->dev, NULL);
1194 if (IS_ERR(i2c->clk)) {
1195 dev_err(&dev->dev, "failed to get the clk: %ld\n", PTR_ERR(i2c->clk));
1196 return PTR_ERR(i2c->clk);
1197 }
1198
1199 i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr;
1200 i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
1201 i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
1202 i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
1203 if (i2c_type != REGS_CE4100)
1204 i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
1205
1206 i2c->iobase = res->start;
1207 i2c->iosize = resource_size(res);
1208
1209 i2c->irq = irq;
1210
1211 i2c->slave_addr = I2C_PXA_SLAVE_ADDR;
1212 i2c->highmode_enter = false;
1213
1214 if (plat) {
1215#ifdef CONFIG_I2C_PXA_SLAVE
1216 i2c->slave_addr = plat->slave_addr;
1217 i2c->slave = plat->slave;
1218#endif
1219 i2c->adap.class = plat->class;
1220 }
1221
1222 if (i2c->high_mode) {
1223 if (i2c->rate) {
1224 clk_set_rate(i2c->clk, i2c->rate);
1225 pr_info("i2c: <%s> set rate to %ld\n",
1226 i2c->adap.name, clk_get_rate(i2c->clk));
1227 } else
1228 pr_warn("i2c: <%s> clock rate not set\n",
1229 i2c->adap.name);
1230 }
1231
1232 clk_prepare_enable(i2c->clk);
1233
1234 if (i2c->use_pio) {
1235 i2c->adap.algo = &i2c_pxa_pio_algorithm;
1236 } else {
1237 i2c->adap.algo = &i2c_pxa_algorithm;
1238 ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler,
1239 IRQF_SHARED | IRQF_NO_SUSPEND,
1240 dev_name(&dev->dev), i2c);
1241 if (ret) {
1242 dev_err(&dev->dev, "failed to request irq: %d\n", ret);
1243 goto ereqirq;
1244 }
1245 }
1246
1247 i2c_pxa_reset(i2c);
1248
1249 i2c->adap.algo_data = i2c;
1250 i2c->adap.dev.parent = &dev->dev;
1251#ifdef CONFIG_OF
1252 i2c->adap.dev.of_node = dev->dev.of_node;
1253#endif
1254
1255 ret = i2c_add_numbered_adapter(&i2c->adap);
1256 if (ret < 0) {
1257 dev_err(&dev->dev, "failed to add bus: %d\n", ret);
1258 goto ereqirq;
1259 }
1260
1261 platform_set_drvdata(dev, i2c);
1262
1263#ifdef CONFIG_I2C_PXA_SLAVE
1264 dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n",
1265 i2c->slave_addr);
1266#else
1267 dev_info(&i2c->adap.dev, " PXA I2C adapter\n");
1268#endif
1269 return 0;
1270
1271ereqirq:
1272 clk_disable_unprepare(i2c->clk);
1273 return ret;
1274}
1275
1276static int i2c_pxa_remove(struct platform_device *dev)
1277{
1278 struct pxa_i2c *i2c = platform_get_drvdata(dev);
1279
1280 i2c_del_adapter(&i2c->adap);
1281
1282 clk_disable_unprepare(i2c->clk);
1283
1284 return 0;
1285}
1286
1287#ifdef CONFIG_PM
1288static int i2c_pxa_suspend_noirq(struct device *dev)
1289{
1290 struct platform_device *pdev = to_platform_device(dev);
1291 struct pxa_i2c *i2c = platform_get_drvdata(pdev);
1292
1293 clk_disable(i2c->clk);
1294
1295 return 0;
1296}
1297
1298static int i2c_pxa_resume_noirq(struct device *dev)
1299{
1300 struct platform_device *pdev = to_platform_device(dev);
1301 struct pxa_i2c *i2c = platform_get_drvdata(pdev);
1302
1303 clk_enable(i2c->clk);
1304 i2c_pxa_reset(i2c);
1305
1306 return 0;
1307}
1308
1309static const struct dev_pm_ops i2c_pxa_dev_pm_ops = {
1310 .suspend_noirq = i2c_pxa_suspend_noirq,
1311 .resume_noirq = i2c_pxa_resume_noirq,
1312};
1313
1314#define I2C_PXA_DEV_PM_OPS (&i2c_pxa_dev_pm_ops)
1315#else
1316#define I2C_PXA_DEV_PM_OPS NULL
1317#endif
1318
1319static struct platform_driver i2c_pxa_driver = {
1320 .probe = i2c_pxa_probe,
1321 .remove = i2c_pxa_remove,
1322 .driver = {
1323 .name = "pxa2xx-i2c",
1324 .pm = I2C_PXA_DEV_PM_OPS,
1325 .of_match_table = i2c_pxa_dt_ids,
1326 },
1327 .id_table = i2c_pxa_id_table,
1328};
1329
1330static int __init i2c_adap_pxa_init(void)
1331{
1332 return platform_driver_register(&i2c_pxa_driver);
1333}
1334
1335static void __exit i2c_adap_pxa_exit(void)
1336{
1337 platform_driver_unregister(&i2c_pxa_driver);
1338}
1339
1340MODULE_LICENSE("GPL");
1341MODULE_ALIAS("platform:pxa2xx-i2c");
1342
1343subsys_initcall(i2c_adap_pxa_init);
1344module_exit(i2c_adap_pxa_exit);
1345