This source file includes following definitions.
- ds1wm_write_register
- ds1wm_read_register
- ds1wm_isr
- ds1wm_reset
- ds1wm_write
- ds1wm_read
- ds1wm_find_divisor
- ds1wm_up
- ds1wm_down
- ds1wm_read_byte
- ds1wm_write_byte
- ds1wm_reset_bus
- ds1wm_search
- ds1wm_probe
- ds1wm_suspend
- ds1wm_resume
- ds1wm_remove
- ds1wm_init
- ds1wm_exit
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14 #include <linux/module.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/irq.h>
18 #include <linux/pm.h>
19 #include <linux/platform_device.h>
20 #include <linux/err.h>
21 #include <linux/delay.h>
22 #include <linux/mfd/core.h>
23 #include <linux/mfd/ds1wm.h>
24 #include <linux/slab.h>
25
26 #include <asm/io.h>
27
28 #include <linux/w1.h>
29
30
31 #define DS1WM_CMD 0x00
32 #define DS1WM_DATA 0x01
33 #define DS1WM_INT 0x02
34 #define DS1WM_INT_EN 0x03
35 #define DS1WM_CLKDIV 0x04
36 #define DS1WM_CNTRL 0x05
37
38 #define DS1WM_CMD_1W_RESET (1 << 0)
39 #define DS1WM_CMD_SRA (1 << 1)
40 #define DS1WM_CMD_DQ_OUTPUT (1 << 2)
41 #define DS1WM_CMD_DQ_INPUT (1 << 3)
42 #define DS1WM_CMD_RST (1 << 5)
43 #define DS1WM_CMD_OD (1 << 7)
44
45 #define DS1WM_INT_PD (1 << 0)
46 #define DS1WM_INT_PDR (1 << 1)
47 #define DS1WM_INT_TBE (1 << 2)
48 #define DS1WM_INT_TSRE (1 << 3)
49 #define DS1WM_INT_RBF (1 << 4)
50 #define DS1WM_INT_RSRF (1 << 5)
51
52 #define DS1WM_INTEN_EPD (1 << 0)
53 #define DS1WM_INTEN_IAS (1 << 1)
54 #define DS1WM_INTEN_ETBE (1 << 2)
55 #define DS1WM_INTEN_ETMT (1 << 3)
56 #define DS1WM_INTEN_ERBF (1 << 4)
57 #define DS1WM_INTEN_ERSRF (1 << 5)
58 #define DS1WM_INTEN_DQO (1 << 6)
59
60 #define DS1WM_INTEN_NOT_IAS (~DS1WM_INTEN_IAS)
61
62 #define DS1WM_TIMEOUT (HZ * 5)
63
64 static struct {
65 unsigned long freq;
66 unsigned long divisor;
67 } freq[] = {
68 { 1000000, 0x80 },
69 { 2000000, 0x84 },
70 { 3000000, 0x81 },
71 { 4000000, 0x88 },
72 { 5000000, 0x82 },
73 { 6000000, 0x85 },
74 { 7000000, 0x83 },
75 { 8000000, 0x8c },
76 { 10000000, 0x86 },
77 { 12000000, 0x89 },
78 { 14000000, 0x87 },
79 { 16000000, 0x90 },
80 { 20000000, 0x8a },
81 { 24000000, 0x8d },
82 { 28000000, 0x8b },
83 { 32000000, 0x94 },
84 { 40000000, 0x8e },
85 { 48000000, 0x91 },
86 { 56000000, 0x8f },
87 { 64000000, 0x98 },
88 { 80000000, 0x92 },
89 { 96000000, 0x95 },
90 { 112000000, 0x93 },
91 { 128000000, 0x9c },
92
93
94 };
95
96 struct ds1wm_data {
97 void __iomem *map;
98 unsigned int bus_shift;
99 bool is_hw_big_endian;
100 struct platform_device *pdev;
101 const struct mfd_cell *cell;
102 int irq;
103 int slave_present;
104 void *reset_complete;
105 void *read_complete;
106 void *write_complete;
107 int read_error;
108
109 u8 read_byte;
110
111
112 u8 int_en_reg_none;
113 unsigned int reset_recover_delay;
114 };
115
116 static inline void ds1wm_write_register(struct ds1wm_data *ds1wm_data, u32 reg,
117 u8 val)
118 {
119 if (ds1wm_data->is_hw_big_endian) {
120 switch (ds1wm_data->bus_shift) {
121 case 0:
122 iowrite8(val, ds1wm_data->map + (reg << 0));
123 break;
124 case 1:
125 iowrite16be((u16)val, ds1wm_data->map + (reg << 1));
126 break;
127 case 2:
128 iowrite32be((u32)val, ds1wm_data->map + (reg << 2));
129 break;
130 }
131 } else {
132 switch (ds1wm_data->bus_shift) {
133 case 0:
134 iowrite8(val, ds1wm_data->map + (reg << 0));
135 break;
136 case 1:
137 iowrite16((u16)val, ds1wm_data->map + (reg << 1));
138 break;
139 case 2:
140 iowrite32((u32)val, ds1wm_data->map + (reg << 2));
141 break;
142 }
143 }
144 }
145
146 static inline u8 ds1wm_read_register(struct ds1wm_data *ds1wm_data, u32 reg)
147 {
148 u32 val = 0;
149
150 if (ds1wm_data->is_hw_big_endian) {
151 switch (ds1wm_data->bus_shift) {
152 case 0:
153 val = ioread8(ds1wm_data->map + (reg << 0));
154 break;
155 case 1:
156 val = ioread16be(ds1wm_data->map + (reg << 1));
157 break;
158 case 2:
159 val = ioread32be(ds1wm_data->map + (reg << 2));
160 break;
161 }
162 } else {
163 switch (ds1wm_data->bus_shift) {
164 case 0:
165 val = ioread8(ds1wm_data->map + (reg << 0));
166 break;
167 case 1:
168 val = ioread16(ds1wm_data->map + (reg << 1));
169 break;
170 case 2:
171 val = ioread32(ds1wm_data->map + (reg << 2));
172 break;
173 }
174 }
175 dev_dbg(&ds1wm_data->pdev->dev,
176 "ds1wm_read_register reg: %d, 32 bit val:%x\n", reg, val);
177 return (u8)val;
178 }
179
180
181 static irqreturn_t ds1wm_isr(int isr, void *data)
182 {
183 struct ds1wm_data *ds1wm_data = data;
184 u8 intr;
185 u8 inten = ds1wm_read_register(ds1wm_data, DS1WM_INT_EN);
186
187
188 if (!(inten & DS1WM_INTEN_NOT_IAS))
189 return IRQ_NONE;
190
191 ds1wm_write_register(ds1wm_data,
192 DS1WM_INT_EN, ds1wm_data->int_en_reg_none);
193
194
195 intr = ds1wm_read_register(ds1wm_data, DS1WM_INT);
196
197 ds1wm_data->slave_present = (intr & DS1WM_INT_PDR) ? 0 : 1;
198
199 if ((intr & DS1WM_INT_TSRE) && ds1wm_data->write_complete) {
200 inten &= ~DS1WM_INTEN_ETMT;
201 complete(ds1wm_data->write_complete);
202 }
203 if (intr & DS1WM_INT_RBF) {
204
205 ds1wm_data->read_byte = ds1wm_read_register(ds1wm_data,
206 DS1WM_DATA);
207 inten &= ~DS1WM_INTEN_ERBF;
208 if (ds1wm_data->read_complete)
209 complete(ds1wm_data->read_complete);
210 }
211 if ((intr & DS1WM_INT_PD) && ds1wm_data->reset_complete) {
212 inten &= ~DS1WM_INTEN_EPD;
213 complete(ds1wm_data->reset_complete);
214 }
215
216 ds1wm_write_register(ds1wm_data, DS1WM_INT_EN, inten);
217 return IRQ_HANDLED;
218 }
219
220 static int ds1wm_reset(struct ds1wm_data *ds1wm_data)
221 {
222 unsigned long timeleft;
223 DECLARE_COMPLETION_ONSTACK(reset_done);
224
225 ds1wm_data->reset_complete = &reset_done;
226
227
228 ds1wm_write_register(ds1wm_data, DS1WM_INT_EN, DS1WM_INTEN_EPD |
229 ds1wm_data->int_en_reg_none);
230
231 ds1wm_write_register(ds1wm_data, DS1WM_CMD, DS1WM_CMD_1W_RESET);
232
233 timeleft = wait_for_completion_timeout(&reset_done, DS1WM_TIMEOUT);
234 ds1wm_data->reset_complete = NULL;
235 if (!timeleft) {
236 dev_err(&ds1wm_data->pdev->dev, "reset failed, timed out\n");
237 return 1;
238 }
239
240 if (!ds1wm_data->slave_present) {
241 dev_dbg(&ds1wm_data->pdev->dev, "reset: no devices found\n");
242 return 1;
243 }
244
245 if (ds1wm_data->reset_recover_delay)
246 msleep(ds1wm_data->reset_recover_delay);
247
248 return 0;
249 }
250
251 static int ds1wm_write(struct ds1wm_data *ds1wm_data, u8 data)
252 {
253 unsigned long timeleft;
254 DECLARE_COMPLETION_ONSTACK(write_done);
255 ds1wm_data->write_complete = &write_done;
256
257 ds1wm_write_register(ds1wm_data, DS1WM_INT_EN,
258 ds1wm_data->int_en_reg_none | DS1WM_INTEN_ETMT);
259
260 ds1wm_write_register(ds1wm_data, DS1WM_DATA, data);
261
262 timeleft = wait_for_completion_timeout(&write_done, DS1WM_TIMEOUT);
263
264 ds1wm_data->write_complete = NULL;
265 if (!timeleft) {
266 dev_err(&ds1wm_data->pdev->dev, "write failed, timed out\n");
267 return -ETIMEDOUT;
268 }
269
270 return 0;
271 }
272
273 static u8 ds1wm_read(struct ds1wm_data *ds1wm_data, unsigned char write_data)
274 {
275 unsigned long timeleft;
276 u8 intEnable = DS1WM_INTEN_ERBF | ds1wm_data->int_en_reg_none;
277 DECLARE_COMPLETION_ONSTACK(read_done);
278
279 ds1wm_read_register(ds1wm_data, DS1WM_DATA);
280
281 ds1wm_data->read_complete = &read_done;
282 ds1wm_write_register(ds1wm_data, DS1WM_INT_EN, intEnable);
283
284 ds1wm_write_register(ds1wm_data, DS1WM_DATA, write_data);
285 timeleft = wait_for_completion_timeout(&read_done, DS1WM_TIMEOUT);
286
287 ds1wm_data->read_complete = NULL;
288 if (!timeleft) {
289 dev_err(&ds1wm_data->pdev->dev, "read failed, timed out\n");
290 ds1wm_data->read_error = -ETIMEDOUT;
291 return 0xFF;
292 }
293 ds1wm_data->read_error = 0;
294 return ds1wm_data->read_byte;
295 }
296
297 static int ds1wm_find_divisor(int gclk)
298 {
299 int i;
300
301 for (i = ARRAY_SIZE(freq)-1; i >= 0; --i)
302 if (gclk >= freq[i].freq)
303 return freq[i].divisor;
304
305 return 0;
306 }
307
308 static void ds1wm_up(struct ds1wm_data *ds1wm_data)
309 {
310 int divisor;
311 struct device *dev = &ds1wm_data->pdev->dev;
312 struct ds1wm_driver_data *plat = dev_get_platdata(dev);
313
314 if (ds1wm_data->cell->enable)
315 ds1wm_data->cell->enable(ds1wm_data->pdev);
316
317 divisor = ds1wm_find_divisor(plat->clock_rate);
318 dev_dbg(dev, "found divisor 0x%x for clock %d\n",
319 divisor, plat->clock_rate);
320 if (divisor == 0) {
321 dev_err(dev, "no suitable divisor for %dHz clock\n",
322 plat->clock_rate);
323 return;
324 }
325 ds1wm_write_register(ds1wm_data, DS1WM_CLKDIV, divisor);
326
327
328 msleep(1);
329
330 ds1wm_reset(ds1wm_data);
331 }
332
333 static void ds1wm_down(struct ds1wm_data *ds1wm_data)
334 {
335 ds1wm_reset(ds1wm_data);
336
337
338 ds1wm_write_register(ds1wm_data, DS1WM_INT_EN,
339 ds1wm_data->int_en_reg_none);
340
341 if (ds1wm_data->cell->disable)
342 ds1wm_data->cell->disable(ds1wm_data->pdev);
343 }
344
345
346
347
348 static u8 ds1wm_read_byte(void *data)
349 {
350 struct ds1wm_data *ds1wm_data = data;
351
352 return ds1wm_read(ds1wm_data, 0xff);
353 }
354
355 static void ds1wm_write_byte(void *data, u8 byte)
356 {
357 struct ds1wm_data *ds1wm_data = data;
358
359 ds1wm_write(ds1wm_data, byte);
360 }
361
362 static u8 ds1wm_reset_bus(void *data)
363 {
364 struct ds1wm_data *ds1wm_data = data;
365
366 ds1wm_reset(ds1wm_data);
367
368 return 0;
369 }
370
371 static void ds1wm_search(void *data, struct w1_master *master_dev,
372 u8 search_type, w1_slave_found_callback slave_found)
373 {
374 struct ds1wm_data *ds1wm_data = data;
375 int i;
376 int ms_discrep_bit = -1;
377 u64 r = 0;
378 u64 r_prime, d;
379 unsigned slaves_found = 0;
380 unsigned int pass = 0;
381
382 dev_dbg(&ds1wm_data->pdev->dev, "search begin\n");
383 while (true) {
384 ++pass;
385 if (pass > 100) {
386 dev_dbg(&ds1wm_data->pdev->dev,
387 "too many attempts (100), search aborted\n");
388 return;
389 }
390
391 mutex_lock(&master_dev->bus_mutex);
392 if (ds1wm_reset(ds1wm_data)) {
393 mutex_unlock(&master_dev->bus_mutex);
394 dev_dbg(&ds1wm_data->pdev->dev,
395 "pass: %d reset error (or no slaves)\n", pass);
396 break;
397 }
398
399 dev_dbg(&ds1wm_data->pdev->dev,
400 "pass: %d r : %0#18llx writing SEARCH_ROM\n", pass, r);
401 ds1wm_write(ds1wm_data, search_type);
402 dev_dbg(&ds1wm_data->pdev->dev,
403 "pass: %d entering ASM\n", pass);
404 ds1wm_write_register(ds1wm_data, DS1WM_CMD, DS1WM_CMD_SRA);
405 dev_dbg(&ds1wm_data->pdev->dev,
406 "pass: %d beginning nibble loop\n", pass);
407
408 r_prime = 0;
409 d = 0;
410
411
412 for (i = 0; i < 16; i++) {
413
414 unsigned char resp, _r, _r_prime, _d;
415
416 _r = (r >> (4*i)) & 0xf;
417 _r = ((_r & 0x1) << 1) |
418 ((_r & 0x2) << 2) |
419 ((_r & 0x4) << 3) |
420 ((_r & 0x8) << 4);
421
422
423 resp = ds1wm_read(ds1wm_data, _r);
424
425 if (ds1wm_data->read_error) {
426 dev_err(&ds1wm_data->pdev->dev,
427 "pass: %d nibble: %d read error\n", pass, i);
428 break;
429 }
430
431 _r_prime = ((resp & 0x02) >> 1) |
432 ((resp & 0x08) >> 2) |
433 ((resp & 0x20) >> 3) |
434 ((resp & 0x80) >> 4);
435
436 _d = ((resp & 0x01) >> 0) |
437 ((resp & 0x04) >> 1) |
438 ((resp & 0x10) >> 2) |
439 ((resp & 0x40) >> 3);
440
441 r_prime |= (unsigned long long) _r_prime << (i * 4);
442 d |= (unsigned long long) _d << (i * 4);
443
444 }
445 if (ds1wm_data->read_error) {
446 mutex_unlock(&master_dev->bus_mutex);
447 dev_err(&ds1wm_data->pdev->dev,
448 "pass: %d read error, retrying\n", pass);
449 break;
450 }
451 dev_dbg(&ds1wm_data->pdev->dev,
452 "pass: %d r\': %0#18llx d:%0#18llx\n",
453 pass, r_prime, d);
454 dev_dbg(&ds1wm_data->pdev->dev,
455 "pass: %d nibble loop complete, exiting ASM\n", pass);
456 ds1wm_write_register(ds1wm_data, DS1WM_CMD, ~DS1WM_CMD_SRA);
457 dev_dbg(&ds1wm_data->pdev->dev,
458 "pass: %d resetting bus\n", pass);
459 ds1wm_reset(ds1wm_data);
460 mutex_unlock(&master_dev->bus_mutex);
461 if ((r_prime & ((u64)1 << 63)) && (d & ((u64)1 << 63))) {
462 dev_err(&ds1wm_data->pdev->dev,
463 "pass: %d bus error, retrying\n", pass);
464 continue;
465 }
466
467
468 dev_dbg(&ds1wm_data->pdev->dev,
469 "pass: %d found %0#18llx\n", pass, r_prime);
470 slave_found(master_dev, r_prime);
471 ++slaves_found;
472 dev_dbg(&ds1wm_data->pdev->dev,
473 "pass: %d complete, preparing next pass\n", pass);
474
475
476
477
478 d &= ~r;
479
480 ms_discrep_bit = fls64(d) - 1;
481 dev_dbg(&ds1wm_data->pdev->dev,
482 "pass: %d new d:%0#18llx MS discrep bit:%d\n",
483 pass, d, ms_discrep_bit);
484
485
486
487 if (ms_discrep_bit == -1)
488 break;
489
490 r = (r & ~(~0ull << (ms_discrep_bit))) | 1 << ms_discrep_bit;
491 }
492 dev_dbg(&ds1wm_data->pdev->dev,
493 "pass: %d total: %d search done ms d bit pos: %d\n", pass,
494 slaves_found, ms_discrep_bit);
495 }
496
497
498
499 static struct w1_bus_master ds1wm_master = {
500 .read_byte = ds1wm_read_byte,
501 .write_byte = ds1wm_write_byte,
502 .reset_bus = ds1wm_reset_bus,
503 .search = ds1wm_search,
504 };
505
506 static int ds1wm_probe(struct platform_device *pdev)
507 {
508 struct ds1wm_data *ds1wm_data;
509 struct ds1wm_driver_data *plat;
510 struct resource *res;
511 int ret;
512 u8 inten;
513
514 if (!pdev)
515 return -ENODEV;
516
517 ds1wm_data = devm_kzalloc(&pdev->dev, sizeof(*ds1wm_data), GFP_KERNEL);
518 if (!ds1wm_data)
519 return -ENOMEM;
520
521 platform_set_drvdata(pdev, ds1wm_data);
522
523 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
524 if (!res)
525 return -ENXIO;
526 ds1wm_data->map = devm_ioremap(&pdev->dev, res->start,
527 resource_size(res));
528 if (!ds1wm_data->map)
529 return -ENOMEM;
530
531 ds1wm_data->pdev = pdev;
532 ds1wm_data->cell = mfd_get_cell(pdev);
533 if (!ds1wm_data->cell)
534 return -ENODEV;
535 plat = dev_get_platdata(&pdev->dev);
536 if (!plat)
537 return -ENODEV;
538
539
540 if (plat->bus_shift > 2) {
541 dev_err(&ds1wm_data->pdev->dev,
542 "illegal bus shift %d, not written",
543 ds1wm_data->bus_shift);
544 return -EINVAL;
545 }
546
547 ds1wm_data->bus_shift = plat->bus_shift;
548
549 if ((8 << ds1wm_data->bus_shift) > resource_size(res)) {
550 dev_err(&ds1wm_data->pdev->dev,
551 "memory resource size %d to small, should be %d\n",
552 (int)resource_size(res),
553 8 << ds1wm_data->bus_shift);
554 return -EINVAL;
555 }
556
557 ds1wm_data->is_hw_big_endian = plat->is_hw_big_endian;
558
559 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
560 if (!res)
561 return -ENXIO;
562 ds1wm_data->irq = res->start;
563 ds1wm_data->int_en_reg_none = (plat->active_high ? DS1WM_INTEN_IAS : 0);
564 ds1wm_data->reset_recover_delay = plat->reset_recover_delay;
565
566
567 inten = ds1wm_read_register(ds1wm_data, DS1WM_INT_EN);
568 ds1wm_write_register(ds1wm_data,
569 DS1WM_INT_EN, ds1wm_data->int_en_reg_none);
570
571 if (res->flags & IORESOURCE_IRQ_HIGHEDGE)
572 irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_EDGE_RISING);
573 if (res->flags & IORESOURCE_IRQ_LOWEDGE)
574 irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_EDGE_FALLING);
575 if (res->flags & IORESOURCE_IRQ_HIGHLEVEL)
576 irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_LEVEL_HIGH);
577 if (res->flags & IORESOURCE_IRQ_LOWLEVEL)
578 irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_LEVEL_LOW);
579
580 ret = devm_request_irq(&pdev->dev, ds1wm_data->irq, ds1wm_isr,
581 IRQF_SHARED, "ds1wm", ds1wm_data);
582 if (ret) {
583 dev_err(&ds1wm_data->pdev->dev,
584 "devm_request_irq %d failed with errno %d\n",
585 ds1wm_data->irq,
586 ret);
587
588 return ret;
589 }
590
591 ds1wm_up(ds1wm_data);
592
593 ds1wm_master.data = (void *)ds1wm_data;
594
595 ret = w1_add_master_device(&ds1wm_master);
596 if (ret)
597 goto err;
598
599 dev_dbg(&ds1wm_data->pdev->dev,
600 "ds1wm: probe successful, IAS: %d, rec.delay: %d, clockrate: %d, bus-shift: %d, is Hw Big Endian: %d\n",
601 plat->active_high,
602 plat->reset_recover_delay,
603 plat->clock_rate,
604 ds1wm_data->bus_shift,
605 ds1wm_data->is_hw_big_endian);
606 return 0;
607
608 err:
609 ds1wm_down(ds1wm_data);
610
611 return ret;
612 }
613
614 #ifdef CONFIG_PM
615 static int ds1wm_suspend(struct platform_device *pdev, pm_message_t state)
616 {
617 struct ds1wm_data *ds1wm_data = platform_get_drvdata(pdev);
618
619 ds1wm_down(ds1wm_data);
620
621 return 0;
622 }
623
624 static int ds1wm_resume(struct platform_device *pdev)
625 {
626 struct ds1wm_data *ds1wm_data = platform_get_drvdata(pdev);
627
628 ds1wm_up(ds1wm_data);
629
630 return 0;
631 }
632 #else
633 #define ds1wm_suspend NULL
634 #define ds1wm_resume NULL
635 #endif
636
637 static int ds1wm_remove(struct platform_device *pdev)
638 {
639 struct ds1wm_data *ds1wm_data = platform_get_drvdata(pdev);
640
641 w1_remove_master_device(&ds1wm_master);
642 ds1wm_down(ds1wm_data);
643
644 return 0;
645 }
646
647 static struct platform_driver ds1wm_driver = {
648 .driver = {
649 .name = "ds1wm",
650 },
651 .probe = ds1wm_probe,
652 .remove = ds1wm_remove,
653 .suspend = ds1wm_suspend,
654 .resume = ds1wm_resume
655 };
656
657 static int __init ds1wm_init(void)
658 {
659 pr_info("DS1WM w1 busmaster driver - (c) 2004 Szabolcs Gyurko\n");
660 return platform_driver_register(&ds1wm_driver);
661 }
662
663 static void __exit ds1wm_exit(void)
664 {
665 platform_driver_unregister(&ds1wm_driver);
666 }
667
668 module_init(ds1wm_init);
669 module_exit(ds1wm_exit);
670
671 MODULE_LICENSE("GPL");
672 MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
673 "Matt Reimer <mreimer@vpop.net>,"
674 "Jean-Francois Dagenais <dagenaisj@sonatest.com>");
675 MODULE_DESCRIPTION("DS1WM w1 busmaster driver");