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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/platform_data/i2c-pxa.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 u32 ilcr;
50 u32 iwcr;
51 u32 fm;
52 u32 hs;
53};
54
55enum pxa_i2c_types {
56 REGS_PXA2XX,
57 REGS_PXA3XX,
58 REGS_CE4100,
59 REGS_PXA910,
60 REGS_A3700,
61};
62
63#define ICR_BUSMODE_FM (1 << 16)
64#define ICR_BUSMODE_HS (1 << 17)
65
66
67
68
69static struct pxa_reg_layout pxa_reg_layout[] = {
70 [REGS_PXA2XX] = {
71 .ibmr = 0x00,
72 .idbr = 0x08,
73 .icr = 0x10,
74 .isr = 0x18,
75 .isar = 0x20,
76 },
77 [REGS_PXA3XX] = {
78 .ibmr = 0x00,
79 .idbr = 0x04,
80 .icr = 0x08,
81 .isr = 0x0c,
82 .isar = 0x10,
83 },
84 [REGS_CE4100] = {
85 .ibmr = 0x14,
86 .idbr = 0x0c,
87 .icr = 0x00,
88 .isr = 0x04,
89
90 },
91 [REGS_PXA910] = {
92 .ibmr = 0x00,
93 .idbr = 0x08,
94 .icr = 0x10,
95 .isr = 0x18,
96 .isar = 0x20,
97 .ilcr = 0x28,
98 .iwcr = 0x30,
99 },
100 [REGS_A3700] = {
101 .ibmr = 0x00,
102 .idbr = 0x04,
103 .icr = 0x08,
104 .isr = 0x0c,
105 .isar = 0x10,
106 .fm = ICR_BUSMODE_FM,
107 .hs = ICR_BUSMODE_HS,
108 },
109};
110
111static const struct platform_device_id i2c_pxa_id_table[] = {
112 { "pxa2xx-i2c", REGS_PXA2XX },
113 { "pxa3xx-pwri2c", REGS_PXA3XX },
114 { "ce4100-i2c", REGS_CE4100 },
115 { "pxa910-i2c", REGS_PXA910 },
116 { "armada-3700-i2c", REGS_A3700 },
117 { },
118};
119MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
120
121
122
123
124
125#define ICR_START (1 << 0)
126#define ICR_STOP (1 << 1)
127#define ICR_ACKNAK (1 << 2)
128#define ICR_TB (1 << 3)
129#define ICR_MA (1 << 4)
130#define ICR_SCLE (1 << 5)
131#define ICR_IUE (1 << 6)
132#define ICR_GCD (1 << 7)
133#define ICR_ITEIE (1 << 8)
134#define ICR_IRFIE (1 << 9)
135#define ICR_BEIE (1 << 10)
136#define ICR_SSDIE (1 << 11)
137#define ICR_ALDIE (1 << 12)
138#define ICR_SADIE (1 << 13)
139#define ICR_UR (1 << 14)
140#define ICR_FM (1 << 15)
141#define ICR_HS (1 << 16)
142#define ICR_GPIOEN (1 << 19)
143
144#define ISR_RWM (1 << 0)
145#define ISR_ACKNAK (1 << 1)
146#define ISR_UB (1 << 2)
147#define ISR_IBB (1 << 3)
148#define ISR_SSD (1 << 4)
149#define ISR_ALD (1 << 5)
150#define ISR_ITE (1 << 6)
151#define ISR_IRF (1 << 7)
152#define ISR_GCAD (1 << 8)
153#define ISR_SAD (1 << 9)
154#define ISR_BED (1 << 10)
155
156
157#define ILCR_SLV_SHIFT 0
158#define ILCR_SLV_MASK (0x1FF << ILCR_SLV_SHIFT)
159#define ILCR_FLV_SHIFT 9
160#define ILCR_FLV_MASK (0x1FF << ILCR_FLV_SHIFT)
161#define ILCR_HLVL_SHIFT 18
162#define ILCR_HLVL_MASK (0x1FF << ILCR_HLVL_SHIFT)
163#define ILCR_HLVH_SHIFT 27
164#define ILCR_HLVH_MASK (0x1F << ILCR_HLVH_SHIFT)
165
166#define IWCR_CNT_SHIFT 0
167#define IWCR_CNT_MASK (0x1F << IWCR_CNT_SHIFT)
168#define IWCR_HS_CNT1_SHIFT 5
169#define IWCR_HS_CNT1_MASK (0x1F << IWCR_HS_CNT1_SHIFT)
170#define IWCR_HS_CNT2_SHIFT 10
171#define IWCR_HS_CNT2_MASK (0x1F << IWCR_HS_CNT2_SHIFT)
172
173struct pxa_i2c {
174 spinlock_t lock;
175 wait_queue_head_t wait;
176 struct i2c_msg *msg;
177 unsigned int msg_num;
178 unsigned int msg_idx;
179 unsigned int msg_ptr;
180 unsigned int slave_addr;
181 unsigned int req_slave_addr;
182
183 struct i2c_adapter adap;
184 struct clk *clk;
185#ifdef CONFIG_I2C_PXA_SLAVE
186 struct i2c_slave_client *slave;
187#endif
188
189 unsigned int irqlogidx;
190 u32 isrlog[32];
191 u32 icrlog[32];
192
193 void __iomem *reg_base;
194 void __iomem *reg_ibmr;
195 void __iomem *reg_idbr;
196 void __iomem *reg_icr;
197 void __iomem *reg_isr;
198 void __iomem *reg_isar;
199 void __iomem *reg_ilcr;
200 void __iomem *reg_iwcr;
201
202 unsigned long iobase;
203 unsigned long iosize;
204
205 int irq;
206 unsigned int use_pio :1;
207 unsigned int fast_mode :1;
208 unsigned int high_mode:1;
209 unsigned char master_code;
210 unsigned long rate;
211 bool highmode_enter;
212 u32 fm_mask;
213 u32 hs_mask;
214};
215
216#define _IBMR(i2c) ((i2c)->reg_ibmr)
217#define _IDBR(i2c) ((i2c)->reg_idbr)
218#define _ICR(i2c) ((i2c)->reg_icr)
219#define _ISR(i2c) ((i2c)->reg_isr)
220#define _ISAR(i2c) ((i2c)->reg_isar)
221#define _ILCR(i2c) ((i2c)->reg_ilcr)
222#define _IWCR(i2c) ((i2c)->reg_iwcr)
223
224
225
226
227#define I2C_PXA_SLAVE_ADDR 0x1
228
229#ifdef DEBUG
230
231struct bits {
232 u32 mask;
233 const char *set;
234 const char *unset;
235};
236#define PXA_BIT(m, s, u) { .mask = m, .set = s, .unset = u }
237
238static inline void
239decode_bits(const char *prefix, const struct bits *bits, int num, u32 val)
240{
241 printk("%s %08x: ", prefix, val);
242 while (num--) {
243 const char *str = val & bits->mask ? bits->set : bits->unset;
244 if (str)
245 printk("%s ", str);
246 bits++;
247 }
248}
249
250static const struct bits isr_bits[] = {
251 PXA_BIT(ISR_RWM, "RX", "TX"),
252 PXA_BIT(ISR_ACKNAK, "NAK", "ACK"),
253 PXA_BIT(ISR_UB, "Bsy", "Rdy"),
254 PXA_BIT(ISR_IBB, "BusBsy", "BusRdy"),
255 PXA_BIT(ISR_SSD, "SlaveStop", NULL),
256 PXA_BIT(ISR_ALD, "ALD", NULL),
257 PXA_BIT(ISR_ITE, "TxEmpty", NULL),
258 PXA_BIT(ISR_IRF, "RxFull", NULL),
259 PXA_BIT(ISR_GCAD, "GenCall", NULL),
260 PXA_BIT(ISR_SAD, "SlaveAddr", NULL),
261 PXA_BIT(ISR_BED, "BusErr", NULL),
262};
263
264static void decode_ISR(unsigned int val)
265{
266 decode_bits(KERN_DEBUG "ISR", isr_bits, ARRAY_SIZE(isr_bits), val);
267 printk("\n");
268}
269
270static const struct bits icr_bits[] = {
271 PXA_BIT(ICR_START, "START", NULL),
272 PXA_BIT(ICR_STOP, "STOP", NULL),
273 PXA_BIT(ICR_ACKNAK, "ACKNAK", NULL),
274 PXA_BIT(ICR_TB, "TB", NULL),
275 PXA_BIT(ICR_MA, "MA", NULL),
276 PXA_BIT(ICR_SCLE, "SCLE", "scle"),
277 PXA_BIT(ICR_IUE, "IUE", "iue"),
278 PXA_BIT(ICR_GCD, "GCD", NULL),
279 PXA_BIT(ICR_ITEIE, "ITEIE", NULL),
280 PXA_BIT(ICR_IRFIE, "IRFIE", NULL),
281 PXA_BIT(ICR_BEIE, "BEIE", NULL),
282 PXA_BIT(ICR_SSDIE, "SSDIE", NULL),
283 PXA_BIT(ICR_ALDIE, "ALDIE", NULL),
284 PXA_BIT(ICR_SADIE, "SADIE", NULL),
285 PXA_BIT(ICR_UR, "UR", "ur"),
286};
287
288#ifdef CONFIG_I2C_PXA_SLAVE
289static void decode_ICR(unsigned int val)
290{
291 decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val);
292 printk("\n");
293}
294#endif
295
296static unsigned int i2c_debug = DEBUG;
297
298static void i2c_pxa_show_state(struct pxa_i2c *i2c, int lno, const char *fname)
299{
300 dev_dbg(&i2c->adap.dev, "state:%s:%d: ISR=%08x, ICR=%08x, IBMR=%02x\n", fname, lno,
301 readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
302}
303
304#define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __func__)
305
306static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
307{
308 unsigned int i;
309 struct device *dev = &i2c->adap.dev;
310
311 dev_err(dev, "slave_0x%x error: %s\n",
312 i2c->req_slave_addr >> 1, why);
313 dev_err(dev, "msg_num: %d msg_idx: %d msg_ptr: %d\n",
314 i2c->msg_num, i2c->msg_idx, i2c->msg_ptr);
315 dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n",
316 readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)),
317 readl(_ISR(i2c)));
318 dev_dbg(dev, "log: ");
319 for (i = 0; i < i2c->irqlogidx; i++)
320 pr_debug("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
321
322 pr_debug("\n");
323}
324
325#else
326
327#define i2c_debug 0
328
329#define show_state(i2c) do { } while (0)
330#define decode_ISR(val) do { } while (0)
331#define decode_ICR(val) do { } while (0)
332#define i2c_pxa_scream_blue_murder(i2c, why) do { } while (0)
333
334#endif
335
336static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
337static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
338
339static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
340{
341 return !(readl(_ICR(i2c)) & ICR_SCLE);
342}
343
344static void i2c_pxa_abort(struct pxa_i2c *i2c)
345{
346 int i = 250;
347
348 if (i2c_pxa_is_slavemode(i2c)) {
349 dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__);
350 return;
351 }
352
353 while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
354 unsigned long icr = readl(_ICR(i2c));
355
356 icr &= ~ICR_START;
357 icr |= ICR_ACKNAK | ICR_STOP | ICR_TB;
358
359 writel(icr, _ICR(i2c));
360
361 show_state(i2c);
362
363 mdelay(1);
364 i --;
365 }
366
367 writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP),
368 _ICR(i2c));
369}
370
371static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c)
372{
373 int timeout = DEF_TIMEOUT;
374
375 while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
376 if ((readl(_ISR(i2c)) & ISR_SAD) != 0)
377 timeout += 4;
378
379 msleep(2);
380 show_state(i2c);
381 }
382
383 if (timeout < 0)
384 show_state(i2c);
385
386 return timeout < 0 ? I2C_RETRY : 0;
387}
388
389static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
390{
391 unsigned long timeout = jiffies + HZ*4;
392
393 while (time_before(jiffies, timeout)) {
394 if (i2c_debug > 1)
395 dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
396 __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
397
398 if (readl(_ISR(i2c)) & ISR_SAD) {
399 if (i2c_debug > 0)
400 dev_dbg(&i2c->adap.dev, "%s: Slave detected\n", __func__);
401 goto out;
402 }
403
404
405
406
407
408 if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 && readl(_IBMR(i2c)) == 3) {
409 if (i2c_debug > 0)
410 dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
411 return 1;
412 }
413
414 msleep(1);
415 }
416
417 if (i2c_debug > 0)
418 dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
419 out:
420 return 0;
421}
422
423static int i2c_pxa_set_master(struct pxa_i2c *i2c)
424{
425 if (i2c_debug)
426 dev_dbg(&i2c->adap.dev, "setting to bus master\n");
427
428 if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) != 0) {
429 dev_dbg(&i2c->adap.dev, "%s: unit is busy\n", __func__);
430 if (!i2c_pxa_wait_master(i2c)) {
431 dev_dbg(&i2c->adap.dev, "%s: error: unit busy\n", __func__);
432 return I2C_RETRY;
433 }
434 }
435
436 writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
437 return 0;
438}
439
440#ifdef CONFIG_I2C_PXA_SLAVE
441static int i2c_pxa_wait_slave(struct pxa_i2c *i2c)
442{
443 unsigned long timeout = jiffies + HZ*1;
444
445
446
447 show_state(i2c);
448
449 while (time_before(jiffies, timeout)) {
450 if (i2c_debug > 1)
451 dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
452 __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
453
454 if ((readl(_ISR(i2c)) & (ISR_UB|ISR_IBB)) == 0 ||
455 (readl(_ISR(i2c)) & ISR_SAD) != 0 ||
456 (readl(_ICR(i2c)) & ICR_SCLE) == 0) {
457 if (i2c_debug > 1)
458 dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
459 return 1;
460 }
461
462 msleep(1);
463 }
464
465 if (i2c_debug > 0)
466 dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
467 return 0;
468}
469
470
471
472
473
474static void i2c_pxa_set_slave(struct pxa_i2c *i2c, int errcode)
475{
476 show_state(i2c);
477
478 if (errcode < 0) {
479 udelay(100);
480 } else {
481
482
483
484 if (readl(_ICR(i2c)) & ICR_STOP) {
485 udelay(100);
486 writel(readl(_ICR(i2c)) & ~ICR_STOP, _ICR(i2c));
487 }
488
489 if (!i2c_pxa_wait_slave(i2c)) {
490 dev_err(&i2c->adap.dev, "%s: wait timedout\n",
491 __func__);
492 return;
493 }
494 }
495
496 writel(readl(_ICR(i2c)) & ~(ICR_STOP|ICR_ACKNAK|ICR_MA), _ICR(i2c));
497 writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
498
499 if (i2c_debug) {
500 dev_dbg(&i2c->adap.dev, "ICR now %08x, ISR %08x\n", readl(_ICR(i2c)), readl(_ISR(i2c)));
501 decode_ICR(readl(_ICR(i2c)));
502 }
503}
504#else
505#define i2c_pxa_set_slave(i2c, err) do { } while (0)
506#endif
507
508static void i2c_pxa_reset(struct pxa_i2c *i2c)
509{
510 pr_debug("Resetting I2C Controller Unit\n");
511
512
513 i2c_pxa_abort(i2c);
514
515
516 writel(ICR_UR, _ICR(i2c));
517 writel(I2C_ISR_INIT, _ISR(i2c));
518 writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
519
520 if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
521 writel(i2c->slave_addr, _ISAR(i2c));
522
523
524 writel(I2C_ICR_INIT | (i2c->fast_mode ? i2c->fm_mask : 0), _ICR(i2c));
525 writel(readl(_ICR(i2c)) | (i2c->high_mode ? i2c->hs_mask : 0), _ICR(i2c));
526
527#ifdef CONFIG_I2C_PXA_SLAVE
528 dev_info(&i2c->adap.dev, "Enabling slave mode\n");
529 writel(readl(_ICR(i2c)) | ICR_SADIE | ICR_ALDIE | ICR_SSDIE, _ICR(i2c));
530#endif
531
532 i2c_pxa_set_slave(i2c, 0);
533
534
535 writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
536 udelay(100);
537}
538
539
540#ifdef CONFIG_I2C_PXA_SLAVE
541
542
543
544
545static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
546{
547 if (isr & ISR_BED) {
548
549 } else {
550 int ret = 0;
551
552 if (i2c->slave != NULL)
553 ret = i2c->slave->read(i2c->slave->data);
554
555 writel(ret, _IDBR(i2c));
556 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
557 }
558}
559
560static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
561{
562 unsigned int byte = readl(_IDBR(i2c));
563
564 if (i2c->slave != NULL)
565 i2c->slave->write(i2c->slave->data, byte);
566
567 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
568}
569
570static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
571{
572 int timeout;
573
574 if (i2c_debug > 0)
575 dev_dbg(&i2c->adap.dev, "SAD, mode is slave-%cx\n",
576 (isr & ISR_RWM) ? 'r' : 't');
577
578 if (i2c->slave != NULL)
579 i2c->slave->event(i2c->slave->data,
580 (isr & ISR_RWM) ? I2C_SLAVE_EVENT_START_READ : I2C_SLAVE_EVENT_START_WRITE);
581
582
583
584
585
586
587 writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
588 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
589
590 timeout = 0x10000;
591
592 while (1) {
593 if ((readl(_IBMR(i2c)) & 2) == 2)
594 break;
595
596 timeout--;
597
598 if (timeout <= 0) {
599 dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
600 break;
601 }
602 }
603
604 writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
605}
606
607static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
608{
609 if (i2c_debug > 2)
610 dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop)\n");
611
612 if (i2c->slave != NULL)
613 i2c->slave->event(i2c->slave->data, I2C_SLAVE_EVENT_STOP);
614
615 if (i2c_debug > 2)
616 dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop) acked\n");
617
618
619
620
621
622 if (i2c->msg)
623 i2c_pxa_master_complete(i2c, I2C_RETRY);
624}
625#else
626static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
627{
628 if (isr & ISR_BED) {
629
630 } else {
631 writel(0, _IDBR(i2c));
632 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
633 }
634}
635
636static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
637{
638 writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
639}
640
641static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
642{
643 int timeout;
644
645
646
647
648
649
650 writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
651 writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
652
653 timeout = 0x10000;
654
655 while (1) {
656 if ((readl(_IBMR(i2c)) & 2) == 2)
657 break;
658
659 timeout--;
660
661 if (timeout <= 0) {
662 dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
663 break;
664 }
665 }
666
667 writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
668}
669
670static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
671{
672 if (i2c->msg)
673 i2c_pxa_master_complete(i2c, I2C_RETRY);
674}
675#endif
676
677
678
679
680
681static inline unsigned int i2c_pxa_addr_byte(struct i2c_msg *msg)
682{
683 unsigned int addr = (msg->addr & 0x7f) << 1;
684
685 if (msg->flags & I2C_M_RD)
686 addr |= 1;
687
688 return addr;
689}
690
691static inline void i2c_pxa_start_message(struct pxa_i2c *i2c)
692{
693 u32 icr;
694
695
696
697
698 writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
699 i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
700
701
702
703
704 icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
705 writel(icr | ICR_START | ICR_TB, _ICR(i2c));
706}
707
708static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
709{
710 u32 icr;
711
712
713
714
715 icr = readl(_ICR(i2c));
716 icr &= ~(ICR_STOP | ICR_ACKNAK);
717 writel(icr, _ICR(i2c));
718}
719
720static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
721{
722
723 long timeout = 2 * DEF_TIMEOUT;
724
725
726
727
728 while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
729 udelay(1000);
730 show_state(i2c);
731 }
732
733 if (timeout < 0) {
734 show_state(i2c);
735 dev_err(&i2c->adap.dev,
736 "i2c_pxa: timeout waiting for bus free\n");
737 return I2C_RETRY;
738 }
739
740
741
742
743 writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
744
745 return 0;
746}
747
748
749
750
751
752
753
754static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
755{
756 u32 icr;
757 long timeout;
758
759 spin_lock_irq(&i2c->lock);
760 i2c->highmode_enter = true;
761 writel(i2c->master_code, _IDBR(i2c));
762
763 icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
764 icr |= ICR_GPIOEN | ICR_START | ICR_TB | ICR_ITEIE;
765 writel(icr, _ICR(i2c));
766
767 spin_unlock_irq(&i2c->lock);
768 timeout = wait_event_timeout(i2c->wait,
769 i2c->highmode_enter == false, HZ * 1);
770
771 i2c->highmode_enter = false;
772
773 return (timeout == 0) ? I2C_RETRY : 0;
774}
775
776static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
777 struct i2c_msg *msg, int num)
778{
779 unsigned long timeout = 500000;
780 int ret = 0;
781
782 ret = i2c_pxa_pio_set_master(i2c);
783 if (ret)
784 goto out;
785
786 i2c->msg = msg;
787 i2c->msg_num = num;
788 i2c->msg_idx = 0;
789 i2c->msg_ptr = 0;
790 i2c->irqlogidx = 0;
791
792 i2c_pxa_start_message(i2c);
793
794 while (i2c->msg_num > 0 && --timeout) {
795 i2c_pxa_handler(0, i2c);
796 udelay(10);
797 }
798
799 i2c_pxa_stop_message(i2c);
800
801
802
803
804 ret = i2c->msg_idx;
805
806out:
807 if (timeout == 0) {
808 i2c_pxa_scream_blue_murder(i2c, "timeout");
809 ret = I2C_RETRY;
810 }
811
812 return ret;
813}
814
815
816
817
818static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
819{
820 long timeout;
821 int ret;
822
823
824
825
826 ret = i2c_pxa_wait_bus_not_busy(i2c);
827 if (ret) {
828 dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
829 goto out;
830 }
831
832
833
834
835 ret = i2c_pxa_set_master(i2c);
836 if (ret) {
837 dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
838 goto out;
839 }
840
841 if (i2c->high_mode) {
842 ret = i2c_pxa_send_mastercode(i2c);
843 if (ret) {
844 dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
845 goto out;
846 }
847 }
848
849 spin_lock_irq(&i2c->lock);
850
851 i2c->msg = msg;
852 i2c->msg_num = num;
853 i2c->msg_idx = 0;
854 i2c->msg_ptr = 0;
855 i2c->irqlogidx = 0;
856
857 i2c_pxa_start_message(i2c);
858
859 spin_unlock_irq(&i2c->lock);
860
861
862
863
864 timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
865 i2c_pxa_stop_message(i2c);
866
867
868
869
870 ret = i2c->msg_idx;
871
872 if (!timeout && i2c->msg_num) {
873 i2c_pxa_scream_blue_murder(i2c, "timeout");
874 ret = I2C_RETRY;
875 }
876
877 out:
878 return ret;
879}
880
881static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
882 struct i2c_msg msgs[], int num)
883{
884 struct pxa_i2c *i2c = adap->algo_data;
885 int ret, i;
886
887
888
889
890
891 if (!(readl(_ICR(i2c)) & ICR_IUE))
892 i2c_pxa_reset(i2c);
893
894 for (i = adap->retries; i >= 0; i--) {
895 ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
896 if (ret != I2C_RETRY)
897 goto out;
898
899 if (i2c_debug)
900 dev_dbg(&adap->dev, "Retrying transmission\n");
901 udelay(100);
902 }
903 i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
904 ret = -EREMOTEIO;
905 out:
906 i2c_pxa_set_slave(i2c, ret);
907 return ret;
908}
909
910
911
912
913static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret)
914{
915 i2c->msg_ptr = 0;
916 i2c->msg = NULL;
917 i2c->msg_idx ++;
918 i2c->msg_num = 0;
919 if (ret)
920 i2c->msg_idx = ret;
921 if (!i2c->use_pio)
922 wake_up(&i2c->wait);
923}
924
925static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
926{
927 u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
928
929 again:
930
931
932
933 if (isr & ISR_ALD) {
934
935
936
937
938 i2c_pxa_scream_blue_murder(i2c, "ALD set");
939
940
941
942
943
944
945
946 return;
947 }
948
949 if ((isr & ISR_BED) &&
950 (!((i2c->msg->flags & I2C_M_IGNORE_NAK) &&
951 (isr & ISR_ACKNAK)))) {
952 int ret = BUS_ERROR;
953
954
955
956
957
958
959 if (isr & ISR_ACKNAK) {
960 if (i2c->msg_ptr == 0 && i2c->msg_idx == 0)
961 ret = I2C_RETRY;
962 else
963 ret = XFER_NAKED;
964 }
965 i2c_pxa_master_complete(i2c, ret);
966 } else if (isr & ISR_RWM) {
967
968
969
970
971 if (i2c->msg_ptr == i2c->msg->len - 1 &&
972 i2c->msg_idx == i2c->msg_num - 1)
973 icr |= ICR_STOP | ICR_ACKNAK;
974
975 icr |= ICR_ALDIE | ICR_TB;
976 } else if (i2c->msg_ptr < i2c->msg->len) {
977
978
979
980 writel(i2c->msg->buf[i2c->msg_ptr++], _IDBR(i2c));
981
982 icr |= ICR_ALDIE | ICR_TB;
983
984
985
986
987
988 if ((i2c->msg_ptr == i2c->msg->len) &&
989 ((i2c->msg->flags & I2C_M_STOP) ||
990 (i2c->msg_idx == i2c->msg_num - 1)))
991 icr |= ICR_STOP;
992
993 } else if (i2c->msg_idx < i2c->msg_num - 1) {
994
995
996
997 i2c->msg_ptr = 0;
998 i2c->msg_idx ++;
999 i2c->msg++;
1000
1001
1002
1003
1004
1005
1006 if (i2c->msg->flags & I2C_M_NOSTART)
1007 goto again;
1008
1009
1010
1011
1012 writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
1013 i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
1014
1015
1016
1017
1018 icr &= ~ICR_ALDIE;
1019 icr |= ICR_START | ICR_TB;
1020 } else {
1021 if (i2c->msg->len == 0) {
1022
1023
1024
1025
1026
1027 i2c_pxa_reset(i2c);
1028 }
1029 i2c_pxa_master_complete(i2c, 0);
1030 }
1031
1032 i2c->icrlog[i2c->irqlogidx-1] = icr;
1033
1034 writel(icr, _ICR(i2c));
1035 show_state(i2c);
1036}
1037
1038static void i2c_pxa_irq_rxfull(struct pxa_i2c *i2c, u32 isr)
1039{
1040 u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
1041
1042
1043
1044
1045 i2c->msg->buf[i2c->msg_ptr++] = readl(_IDBR(i2c));
1046
1047 if (i2c->msg_ptr < i2c->msg->len) {
1048
1049
1050
1051
1052 if (i2c->msg_ptr == i2c->msg->len - 1)
1053 icr |= ICR_STOP | ICR_ACKNAK;
1054
1055 icr |= ICR_ALDIE | ICR_TB;
1056 } else {
1057 i2c_pxa_master_complete(i2c, 0);
1058 }
1059
1060 i2c->icrlog[i2c->irqlogidx-1] = icr;
1061
1062 writel(icr, _ICR(i2c));
1063}
1064
1065#define VALID_INT_SOURCE (ISR_SSD | ISR_ALD | ISR_ITE | ISR_IRF | \
1066 ISR_SAD | ISR_BED)
1067static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
1068{
1069 struct pxa_i2c *i2c = dev_id;
1070 u32 isr = readl(_ISR(i2c));
1071
1072 if (!(isr & VALID_INT_SOURCE))
1073 return IRQ_NONE;
1074
1075 if (i2c_debug > 2 && 0) {
1076 dev_dbg(&i2c->adap.dev, "%s: ISR=%08x, ICR=%08x, IBMR=%02x\n",
1077 __func__, isr, readl(_ICR(i2c)), readl(_IBMR(i2c)));
1078 decode_ISR(isr);
1079 }
1080
1081 if (i2c->irqlogidx < ARRAY_SIZE(i2c->isrlog))
1082 i2c->isrlog[i2c->irqlogidx++] = isr;
1083
1084 show_state(i2c);
1085
1086
1087
1088
1089 writel(isr & VALID_INT_SOURCE, _ISR(i2c));
1090
1091 if (isr & ISR_SAD)
1092 i2c_pxa_slave_start(i2c, isr);
1093 if (isr & ISR_SSD)
1094 i2c_pxa_slave_stop(i2c);
1095
1096 if (i2c_pxa_is_slavemode(i2c)) {
1097 if (isr & ISR_ITE)
1098 i2c_pxa_slave_txempty(i2c, isr);
1099 if (isr & ISR_IRF)
1100 i2c_pxa_slave_rxfull(i2c, isr);
1101 } else if (i2c->msg && (!i2c->highmode_enter)) {
1102 if (isr & ISR_ITE)
1103 i2c_pxa_irq_txempty(i2c, isr);
1104 if (isr & ISR_IRF)
1105 i2c_pxa_irq_rxfull(i2c, isr);
1106 } else if ((isr & ISR_ITE) && i2c->highmode_enter) {
1107 i2c->highmode_enter = false;
1108 wake_up(&i2c->wait);
1109 } else {
1110 i2c_pxa_scream_blue_murder(i2c, "spurious irq");
1111 }
1112
1113 return IRQ_HANDLED;
1114}
1115
1116
1117static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
1118{
1119 struct pxa_i2c *i2c = adap->algo_data;
1120 int ret, i;
1121
1122 for (i = adap->retries; i >= 0; i--) {
1123 ret = i2c_pxa_do_xfer(i2c, msgs, num);
1124 if (ret != I2C_RETRY)
1125 goto out;
1126
1127 if (i2c_debug)
1128 dev_dbg(&adap->dev, "Retrying transmission\n");
1129 udelay(100);
1130 }
1131 i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
1132 ret = -EREMOTEIO;
1133 out:
1134 i2c_pxa_set_slave(i2c, ret);
1135 return ret;
1136}
1137
1138static u32 i2c_pxa_functionality(struct i2c_adapter *adap)
1139{
1140 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
1141 I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
1142}
1143
1144static const struct i2c_algorithm i2c_pxa_algorithm = {
1145 .master_xfer = i2c_pxa_xfer,
1146 .functionality = i2c_pxa_functionality,
1147};
1148
1149static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
1150 .master_xfer = i2c_pxa_pio_xfer,
1151 .functionality = i2c_pxa_functionality,
1152};
1153
1154static const struct of_device_id i2c_pxa_dt_ids[] = {
1155 { .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
1156 { .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
1157 { .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
1158 { .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 },
1159 {}
1160};
1161MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
1162
1163static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
1164 enum pxa_i2c_types *i2c_types)
1165{
1166 struct device_node *np = pdev->dev.of_node;
1167 const struct of_device_id *of_id =
1168 of_match_device(i2c_pxa_dt_ids, &pdev->dev);
1169
1170 if (!of_id)
1171 return 1;
1172
1173
1174 i2c->adap.nr = -1;
1175
1176 if (of_get_property(np, "mrvl,i2c-polling", NULL))
1177 i2c->use_pio = 1;
1178 if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
1179 i2c->fast_mode = 1;
1180
1181 *i2c_types = (enum pxa_i2c_types)(of_id->data);
1182
1183 return 0;
1184}
1185
1186static int i2c_pxa_probe_pdata(struct platform_device *pdev,
1187 struct pxa_i2c *i2c,
1188 enum pxa_i2c_types *i2c_types)
1189{
1190 struct i2c_pxa_platform_data *plat = dev_get_platdata(&pdev->dev);
1191 const struct platform_device_id *id = platform_get_device_id(pdev);
1192
1193 *i2c_types = id->driver_data;
1194 if (plat) {
1195 i2c->use_pio = plat->use_pio;
1196 i2c->fast_mode = plat->fast_mode;
1197 i2c->high_mode = plat->high_mode;
1198 i2c->master_code = plat->master_code;
1199 if (!i2c->master_code)
1200 i2c->master_code = 0xe;
1201 i2c->rate = plat->rate;
1202 }
1203 return 0;
1204}
1205
1206static int i2c_pxa_probe(struct platform_device *dev)
1207{
1208 struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
1209 enum pxa_i2c_types i2c_type;
1210 struct pxa_i2c *i2c;
1211 struct resource *res = NULL;
1212 int ret, irq;
1213
1214 i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL);
1215 if (!i2c)
1216 return -ENOMEM;
1217
1218 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
1219 i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
1220 if (IS_ERR(i2c->reg_base))
1221 return PTR_ERR(i2c->reg_base);
1222
1223 irq = platform_get_irq(dev, 0);
1224 if (irq < 0) {
1225 dev_err(&dev->dev, "no irq resource: %d\n", irq);
1226 return irq;
1227 }
1228
1229
1230 i2c->adap.nr = dev->id;
1231
1232 ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
1233 if (ret > 0)
1234 ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
1235 if (ret < 0)
1236 return ret;
1237
1238 i2c->adap.owner = THIS_MODULE;
1239 i2c->adap.retries = 5;
1240
1241 spin_lock_init(&i2c->lock);
1242 init_waitqueue_head(&i2c->wait);
1243
1244 strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
1245
1246 i2c->clk = devm_clk_get(&dev->dev, NULL);
1247 if (IS_ERR(i2c->clk)) {
1248 dev_err(&dev->dev, "failed to get the clk: %ld\n", PTR_ERR(i2c->clk));
1249 return PTR_ERR(i2c->clk);
1250 }
1251
1252 i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr;
1253 i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
1254 i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
1255 i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
1256 i2c->fm_mask = pxa_reg_layout[i2c_type].fm ? : ICR_FM;
1257 i2c->hs_mask = pxa_reg_layout[i2c_type].hs ? : ICR_HS;
1258
1259 if (i2c_type != REGS_CE4100)
1260 i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
1261
1262 if (i2c_type == REGS_PXA910) {
1263 i2c->reg_ilcr = i2c->reg_base + pxa_reg_layout[i2c_type].ilcr;
1264 i2c->reg_iwcr = i2c->reg_base + pxa_reg_layout[i2c_type].iwcr;
1265 }
1266
1267 i2c->iobase = res->start;
1268 i2c->iosize = resource_size(res);
1269
1270 i2c->irq = irq;
1271
1272 i2c->slave_addr = I2C_PXA_SLAVE_ADDR;
1273 i2c->highmode_enter = false;
1274
1275 if (plat) {
1276#ifdef CONFIG_I2C_PXA_SLAVE
1277 i2c->slave_addr = plat->slave_addr;
1278 i2c->slave = plat->slave;
1279#endif
1280 i2c->adap.class = plat->class;
1281 }
1282
1283 if (i2c->high_mode) {
1284 if (i2c->rate) {
1285 clk_set_rate(i2c->clk, i2c->rate);
1286 pr_info("i2c: <%s> set rate to %ld\n",
1287 i2c->adap.name, clk_get_rate(i2c->clk));
1288 } else
1289 pr_warn("i2c: <%s> clock rate not set\n",
1290 i2c->adap.name);
1291 }
1292
1293 clk_prepare_enable(i2c->clk);
1294
1295 if (i2c->use_pio) {
1296 i2c->adap.algo = &i2c_pxa_pio_algorithm;
1297 } else {
1298 i2c->adap.algo = &i2c_pxa_algorithm;
1299 ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler,
1300 IRQF_SHARED | IRQF_NO_SUSPEND,
1301 dev_name(&dev->dev), i2c);
1302 if (ret) {
1303 dev_err(&dev->dev, "failed to request irq: %d\n", ret);
1304 goto ereqirq;
1305 }
1306 }
1307
1308 i2c_pxa_reset(i2c);
1309
1310 i2c->adap.algo_data = i2c;
1311 i2c->adap.dev.parent = &dev->dev;
1312#ifdef CONFIG_OF
1313 i2c->adap.dev.of_node = dev->dev.of_node;
1314#endif
1315
1316 ret = i2c_add_numbered_adapter(&i2c->adap);
1317 if (ret < 0)
1318 goto ereqirq;
1319
1320 platform_set_drvdata(dev, i2c);
1321
1322#ifdef CONFIG_I2C_PXA_SLAVE
1323 dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n",
1324 i2c->slave_addr);
1325#else
1326 dev_info(&i2c->adap.dev, " PXA I2C adapter\n");
1327#endif
1328 return 0;
1329
1330ereqirq:
1331 clk_disable_unprepare(i2c->clk);
1332 return ret;
1333}
1334
1335static int i2c_pxa_remove(struct platform_device *dev)
1336{
1337 struct pxa_i2c *i2c = platform_get_drvdata(dev);
1338
1339 i2c_del_adapter(&i2c->adap);
1340
1341 clk_disable_unprepare(i2c->clk);
1342
1343 return 0;
1344}
1345
1346#ifdef CONFIG_PM
1347static int i2c_pxa_suspend_noirq(struct device *dev)
1348{
1349 struct pxa_i2c *i2c = dev_get_drvdata(dev);
1350
1351 clk_disable(i2c->clk);
1352
1353 return 0;
1354}
1355
1356static int i2c_pxa_resume_noirq(struct device *dev)
1357{
1358 struct pxa_i2c *i2c = dev_get_drvdata(dev);
1359
1360 clk_enable(i2c->clk);
1361 i2c_pxa_reset(i2c);
1362
1363 return 0;
1364}
1365
1366static const struct dev_pm_ops i2c_pxa_dev_pm_ops = {
1367 .suspend_noirq = i2c_pxa_suspend_noirq,
1368 .resume_noirq = i2c_pxa_resume_noirq,
1369};
1370
1371#define I2C_PXA_DEV_PM_OPS (&i2c_pxa_dev_pm_ops)
1372#else
1373#define I2C_PXA_DEV_PM_OPS NULL
1374#endif
1375
1376static struct platform_driver i2c_pxa_driver = {
1377 .probe = i2c_pxa_probe,
1378 .remove = i2c_pxa_remove,
1379 .driver = {
1380 .name = "pxa2xx-i2c",
1381 .pm = I2C_PXA_DEV_PM_OPS,
1382 .of_match_table = i2c_pxa_dt_ids,
1383 },
1384 .id_table = i2c_pxa_id_table,
1385};
1386
1387static int __init i2c_adap_pxa_init(void)
1388{
1389 return platform_driver_register(&i2c_pxa_driver);
1390}
1391
1392static void __exit i2c_adap_pxa_exit(void)
1393{
1394 platform_driver_unregister(&i2c_pxa_driver);
1395}
1396
1397MODULE_LICENSE("GPL");
1398MODULE_ALIAS("platform:pxa2xx-i2c");
1399
1400subsys_initcall(i2c_adap_pxa_init);
1401module_exit(i2c_adap_pxa_exit);
1402
