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Merge tag 'v5.11-rc1' into spi-5.11
[mirror_ubuntu-jammy-kernel.git] / drivers / rtc / rtc-bd70528.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 //
3 // Copyright (C) 2018 ROHM Semiconductors
4 //
5 // RTC driver for ROHM BD70528 PMIC
6
7 #include <linux/bcd.h>
8 #include <linux/mfd/rohm-bd70528.h>
9 #include <linux/mfd/rohm-bd71828.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/regmap.h>
14 #include <linux/rtc.h>
15
16 /*
17 * We read regs RTC_SEC => RTC_YEAR
18 * this struct is ordered according to chip registers.
19 * Keep it u8 only (or packed) to avoid padding issues.
20 */
21 struct bd70528_rtc_day {
22 u8 sec;
23 u8 min;
24 u8 hour;
25 } __packed;
26
27 struct bd70528_rtc_data {
28 struct bd70528_rtc_day time;
29 u8 week;
30 u8 day;
31 u8 month;
32 u8 year;
33 } __packed;
34
35 struct bd70528_rtc_wake {
36 struct bd70528_rtc_day time;
37 u8 ctrl;
38 } __packed;
39
40 struct bd71828_rtc_alm {
41 struct bd70528_rtc_data alm0;
42 struct bd70528_rtc_data alm1;
43 u8 alm_mask;
44 u8 alm1_mask;
45 } __packed;
46
47 struct bd70528_rtc_alm {
48 struct bd70528_rtc_data data;
49 u8 alm_mask;
50 u8 alm_repeat;
51 } __packed;
52
53 struct bd70528_rtc {
54 struct rohm_regmap_dev *parent;
55 struct device *dev;
56 u8 reg_time_start;
57 bool has_rtc_timers;
58 };
59
60 static int bd70528_set_wake(struct rohm_regmap_dev *bd70528,
61 int enable, int *old_state)
62 {
63 int ret;
64 unsigned int ctrl_reg;
65
66 ret = regmap_read(bd70528->regmap, BD70528_REG_WAKE_EN, &ctrl_reg);
67 if (ret)
68 return ret;
69
70 if (old_state) {
71 if (ctrl_reg & BD70528_MASK_WAKE_EN)
72 *old_state |= BD70528_WAKE_STATE_BIT;
73 else
74 *old_state &= ~BD70528_WAKE_STATE_BIT;
75
76 if (!enable == !(*old_state & BD70528_WAKE_STATE_BIT))
77 return 0;
78 }
79
80 if (enable)
81 ctrl_reg |= BD70528_MASK_WAKE_EN;
82 else
83 ctrl_reg &= ~BD70528_MASK_WAKE_EN;
84
85 return regmap_write(bd70528->regmap, BD70528_REG_WAKE_EN,
86 ctrl_reg);
87 }
88
89 static int bd70528_set_elapsed_tmr(struct rohm_regmap_dev *bd70528,
90 int enable, int *old_state)
91 {
92 int ret;
93 unsigned int ctrl_reg;
94
95 /*
96 * TBD
97 * What is the purpose of elapsed timer ?
98 * Is the timeout registers counting down, or is the disable - re-enable
99 * going to restart the elapsed-time counting? If counting is restarted
100 * the timeout should be decreased by the amount of time that has
101 * elapsed since starting the timer. Maybe we should store the monotonic
102 * clock value when timer is started so that if RTC is set while timer
103 * is armed we could do the compensation. This is a hack if RTC/system
104 * clk are drifting. OTOH, RTC controlled via I2C is in any case
105 * inaccurate...
106 */
107 ret = regmap_read(bd70528->regmap, BD70528_REG_ELAPSED_TIMER_EN,
108 &ctrl_reg);
109 if (ret)
110 return ret;
111
112 if (old_state) {
113 if (ctrl_reg & BD70528_MASK_ELAPSED_TIMER_EN)
114 *old_state |= BD70528_ELAPSED_STATE_BIT;
115 else
116 *old_state &= ~BD70528_ELAPSED_STATE_BIT;
117
118 if ((!enable) == (!(*old_state & BD70528_ELAPSED_STATE_BIT)))
119 return 0;
120 }
121
122 if (enable)
123 ctrl_reg |= BD70528_MASK_ELAPSED_TIMER_EN;
124 else
125 ctrl_reg &= ~BD70528_MASK_ELAPSED_TIMER_EN;
126
127 return regmap_write(bd70528->regmap, BD70528_REG_ELAPSED_TIMER_EN,
128 ctrl_reg);
129 }
130
131 static int bd70528_set_rtc_based_timers(struct bd70528_rtc *r, int new_state,
132 int *old_state)
133 {
134 int ret;
135
136 ret = bd70528_wdt_set(r->parent, new_state & BD70528_WDT_STATE_BIT,
137 old_state);
138 if (ret) {
139 dev_err(r->dev,
140 "Failed to disable WDG for RTC setting (%d)\n", ret);
141 return ret;
142 }
143 ret = bd70528_set_elapsed_tmr(r->parent,
144 new_state & BD70528_ELAPSED_STATE_BIT,
145 old_state);
146 if (ret) {
147 dev_err(r->dev,
148 "Failed to disable 'elapsed timer' for RTC setting\n");
149 return ret;
150 }
151 ret = bd70528_set_wake(r->parent, new_state & BD70528_WAKE_STATE_BIT,
152 old_state);
153 if (ret) {
154 dev_err(r->dev,
155 "Failed to disable 'wake timer' for RTC setting\n");
156 return ret;
157 }
158
159 return ret;
160 }
161
162 static int bd70528_re_enable_rtc_based_timers(struct bd70528_rtc *r,
163 int old_state)
164 {
165 if (!r->has_rtc_timers)
166 return 0;
167
168 return bd70528_set_rtc_based_timers(r, old_state, NULL);
169 }
170
171 static int bd70528_disable_rtc_based_timers(struct bd70528_rtc *r,
172 int *old_state)
173 {
174 if (!r->has_rtc_timers)
175 return 0;
176
177 return bd70528_set_rtc_based_timers(r, 0, old_state);
178 }
179
180 static inline void tmday2rtc(struct rtc_time *t, struct bd70528_rtc_day *d)
181 {
182 d->sec &= ~BD70528_MASK_RTC_SEC;
183 d->min &= ~BD70528_MASK_RTC_MINUTE;
184 d->hour &= ~BD70528_MASK_RTC_HOUR;
185 d->sec |= bin2bcd(t->tm_sec);
186 d->min |= bin2bcd(t->tm_min);
187 d->hour |= bin2bcd(t->tm_hour);
188 }
189
190 static inline void tm2rtc(struct rtc_time *t, struct bd70528_rtc_data *r)
191 {
192 r->day &= ~BD70528_MASK_RTC_DAY;
193 r->week &= ~BD70528_MASK_RTC_WEEK;
194 r->month &= ~BD70528_MASK_RTC_MONTH;
195 /*
196 * PM and 24H bits are not used by Wake - thus we clear them
197 * here and not in tmday2rtc() which is also used by wake.
198 */
199 r->time.hour &= ~(BD70528_MASK_RTC_HOUR_PM | BD70528_MASK_RTC_HOUR_24H);
200
201 tmday2rtc(t, &r->time);
202 /*
203 * We do always set time in 24H mode.
204 */
205 r->time.hour |= BD70528_MASK_RTC_HOUR_24H;
206 r->day |= bin2bcd(t->tm_mday);
207 r->week |= bin2bcd(t->tm_wday);
208 r->month |= bin2bcd(t->tm_mon + 1);
209 r->year = bin2bcd(t->tm_year - 100);
210 }
211
212 static inline void rtc2tm(struct bd70528_rtc_data *r, struct rtc_time *t)
213 {
214 t->tm_sec = bcd2bin(r->time.sec & BD70528_MASK_RTC_SEC);
215 t->tm_min = bcd2bin(r->time.min & BD70528_MASK_RTC_MINUTE);
216 t->tm_hour = bcd2bin(r->time.hour & BD70528_MASK_RTC_HOUR);
217 /*
218 * If RTC is in 12H mode, then bit BD70528_MASK_RTC_HOUR_PM
219 * is not BCD value but tells whether it is AM or PM
220 */
221 if (!(r->time.hour & BD70528_MASK_RTC_HOUR_24H)) {
222 t->tm_hour %= 12;
223 if (r->time.hour & BD70528_MASK_RTC_HOUR_PM)
224 t->tm_hour += 12;
225 }
226 t->tm_mday = bcd2bin(r->day & BD70528_MASK_RTC_DAY);
227 t->tm_mon = bcd2bin(r->month & BD70528_MASK_RTC_MONTH) - 1;
228 t->tm_year = 100 + bcd2bin(r->year & BD70528_MASK_RTC_YEAR);
229 t->tm_wday = bcd2bin(r->week & BD70528_MASK_RTC_WEEK);
230 }
231
232 static int bd71828_set_alarm(struct device *dev, struct rtc_wkalrm *a)
233 {
234 int ret;
235 struct bd71828_rtc_alm alm;
236 struct bd70528_rtc *r = dev_get_drvdata(dev);
237 struct rohm_regmap_dev *parent = r->parent;
238
239 ret = regmap_bulk_read(parent->regmap, BD71828_REG_RTC_ALM_START,
240 &alm, sizeof(alm));
241 if (ret) {
242 dev_err(dev, "Failed to read alarm regs\n");
243 return ret;
244 }
245
246 tm2rtc(&a->time, &alm.alm0);
247
248 if (!a->enabled)
249 alm.alm_mask &= ~BD70528_MASK_ALM_EN;
250 else
251 alm.alm_mask |= BD70528_MASK_ALM_EN;
252
253 ret = regmap_bulk_write(parent->regmap, BD71828_REG_RTC_ALM_START,
254 &alm, sizeof(alm));
255 if (ret)
256 dev_err(dev, "Failed to set alarm time\n");
257
258 return ret;
259
260 }
261
262 static int bd70528_set_alarm(struct device *dev, struct rtc_wkalrm *a)
263 {
264 struct bd70528_rtc_wake wake;
265 struct bd70528_rtc_alm alm;
266 int ret;
267 struct bd70528_rtc *r = dev_get_drvdata(dev);
268 struct rohm_regmap_dev *parent = r->parent;
269
270 ret = regmap_bulk_read(parent->regmap, BD70528_REG_RTC_WAKE_START,
271 &wake, sizeof(wake));
272 if (ret) {
273 dev_err(dev, "Failed to read wake regs\n");
274 return ret;
275 }
276
277 ret = regmap_bulk_read(parent->regmap, BD70528_REG_RTC_ALM_START,
278 &alm, sizeof(alm));
279 if (ret) {
280 dev_err(dev, "Failed to read alarm regs\n");
281 return ret;
282 }
283
284 tm2rtc(&a->time, &alm.data);
285 tmday2rtc(&a->time, &wake.time);
286
287 if (a->enabled) {
288 alm.alm_mask &= ~BD70528_MASK_ALM_EN;
289 wake.ctrl |= BD70528_MASK_WAKE_EN;
290 } else {
291 alm.alm_mask |= BD70528_MASK_ALM_EN;
292 wake.ctrl &= ~BD70528_MASK_WAKE_EN;
293 }
294
295 ret = regmap_bulk_write(parent->regmap,
296 BD70528_REG_RTC_WAKE_START, &wake,
297 sizeof(wake));
298 if (ret) {
299 dev_err(dev, "Failed to set wake time\n");
300 return ret;
301 }
302 ret = regmap_bulk_write(parent->regmap, BD70528_REG_RTC_ALM_START,
303 &alm, sizeof(alm));
304 if (ret)
305 dev_err(dev, "Failed to set alarm time\n");
306
307 return ret;
308 }
309
310 static int bd71828_read_alarm(struct device *dev, struct rtc_wkalrm *a)
311 {
312 int ret;
313 struct bd71828_rtc_alm alm;
314 struct bd70528_rtc *r = dev_get_drvdata(dev);
315 struct rohm_regmap_dev *parent = r->parent;
316
317 ret = regmap_bulk_read(parent->regmap, BD71828_REG_RTC_ALM_START,
318 &alm, sizeof(alm));
319 if (ret) {
320 dev_err(dev, "Failed to read alarm regs\n");
321 return ret;
322 }
323
324 rtc2tm(&alm.alm0, &a->time);
325 a->time.tm_mday = -1;
326 a->time.tm_mon = -1;
327 a->time.tm_year = -1;
328 a->enabled = !!(alm.alm_mask & BD70528_MASK_ALM_EN);
329 a->pending = 0;
330
331 return 0;
332 }
333
334 static int bd70528_read_alarm(struct device *dev, struct rtc_wkalrm *a)
335 {
336 struct bd70528_rtc_alm alm;
337 int ret;
338 struct bd70528_rtc *r = dev_get_drvdata(dev);
339 struct rohm_regmap_dev *parent = r->parent;
340
341 ret = regmap_bulk_read(parent->regmap, BD70528_REG_RTC_ALM_START,
342 &alm, sizeof(alm));
343 if (ret) {
344 dev_err(dev, "Failed to read alarm regs\n");
345 return ret;
346 }
347
348 rtc2tm(&alm.data, &a->time);
349 a->time.tm_mday = -1;
350 a->time.tm_mon = -1;
351 a->time.tm_year = -1;
352 a->enabled = !(alm.alm_mask & BD70528_MASK_ALM_EN);
353 a->pending = 0;
354
355 return 0;
356 }
357
358 static int bd70528_set_time_locked(struct device *dev, struct rtc_time *t)
359 {
360 int ret, tmpret, old_states;
361 struct bd70528_rtc_data rtc_data;
362 struct bd70528_rtc *r = dev_get_drvdata(dev);
363 struct rohm_regmap_dev *parent = r->parent;
364
365 ret = bd70528_disable_rtc_based_timers(r, &old_states);
366 if (ret)
367 return ret;
368
369 tmpret = regmap_bulk_read(parent->regmap,
370 r->reg_time_start, &rtc_data,
371 sizeof(rtc_data));
372 if (tmpret) {
373 dev_err(dev, "Failed to read RTC time registers\n");
374 goto renable_out;
375 }
376 tm2rtc(t, &rtc_data);
377
378 tmpret = regmap_bulk_write(parent->regmap,
379 r->reg_time_start, &rtc_data,
380 sizeof(rtc_data));
381 if (tmpret) {
382 dev_err(dev, "Failed to set RTC time\n");
383 goto renable_out;
384 }
385
386 renable_out:
387 ret = bd70528_re_enable_rtc_based_timers(r, old_states);
388 if (tmpret)
389 ret = tmpret;
390
391 return ret;
392 }
393
394 static int bd71828_set_time(struct device *dev, struct rtc_time *t)
395 {
396 return bd70528_set_time_locked(dev, t);
397 }
398
399 static int bd70528_set_time(struct device *dev, struct rtc_time *t)
400 {
401 int ret;
402 struct bd70528_rtc *r = dev_get_drvdata(dev);
403
404 bd70528_wdt_lock(r->parent);
405 ret = bd70528_set_time_locked(dev, t);
406 bd70528_wdt_unlock(r->parent);
407 return ret;
408 }
409
410 static int bd70528_get_time(struct device *dev, struct rtc_time *t)
411 {
412 struct bd70528_rtc *r = dev_get_drvdata(dev);
413 struct rohm_regmap_dev *parent = r->parent;
414 struct bd70528_rtc_data rtc_data;
415 int ret;
416
417 /* read the RTC date and time registers all at once */
418 ret = regmap_bulk_read(parent->regmap,
419 r->reg_time_start, &rtc_data,
420 sizeof(rtc_data));
421 if (ret) {
422 dev_err(dev, "Failed to read RTC time (err %d)\n", ret);
423 return ret;
424 }
425
426 rtc2tm(&rtc_data, t);
427
428 return 0;
429 }
430
431 static int bd70528_alm_enable(struct device *dev, unsigned int enabled)
432 {
433 int ret;
434 unsigned int enableval = BD70528_MASK_ALM_EN;
435 struct bd70528_rtc *r = dev_get_drvdata(dev);
436
437 if (enabled)
438 enableval = 0;
439
440 bd70528_wdt_lock(r->parent);
441 ret = bd70528_set_wake(r->parent, enabled, NULL);
442 if (ret) {
443 dev_err(dev, "Failed to change wake state\n");
444 goto out_unlock;
445 }
446 ret = regmap_update_bits(r->parent->regmap, BD70528_REG_RTC_ALM_MASK,
447 BD70528_MASK_ALM_EN, enableval);
448 if (ret)
449 dev_err(dev, "Failed to change alarm state\n");
450
451 out_unlock:
452 bd70528_wdt_unlock(r->parent);
453 return ret;
454 }
455
456 static int bd71828_alm_enable(struct device *dev, unsigned int enabled)
457 {
458 int ret;
459 struct bd70528_rtc *r = dev_get_drvdata(dev);
460 unsigned int enableval = BD70528_MASK_ALM_EN;
461
462 if (!enabled)
463 enableval = 0;
464
465 ret = regmap_update_bits(r->parent->regmap, BD71828_REG_RTC_ALM0_MASK,
466 BD70528_MASK_ALM_EN, enableval);
467 if (ret)
468 dev_err(dev, "Failed to change alarm state\n");
469
470 return ret;
471 }
472
473 static const struct rtc_class_ops bd70528_rtc_ops = {
474 .read_time = bd70528_get_time,
475 .set_time = bd70528_set_time,
476 .read_alarm = bd70528_read_alarm,
477 .set_alarm = bd70528_set_alarm,
478 .alarm_irq_enable = bd70528_alm_enable,
479 };
480
481 static const struct rtc_class_ops bd71828_rtc_ops = {
482 .read_time = bd70528_get_time,
483 .set_time = bd71828_set_time,
484 .read_alarm = bd71828_read_alarm,
485 .set_alarm = bd71828_set_alarm,
486 .alarm_irq_enable = bd71828_alm_enable,
487 };
488
489 static irqreturn_t alm_hndlr(int irq, void *data)
490 {
491 struct rtc_device *rtc = data;
492
493 rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF | RTC_PF);
494 return IRQ_HANDLED;
495 }
496
497 static int bd70528_probe(struct platform_device *pdev)
498 {
499 struct bd70528_rtc *bd_rtc;
500 const struct rtc_class_ops *rtc_ops;
501 struct rohm_regmap_dev *parent;
502 const char *irq_name;
503 int ret;
504 struct rtc_device *rtc;
505 int irq;
506 unsigned int hr;
507 bool enable_main_irq = false;
508 u8 hour_reg;
509 enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;
510
511 parent = dev_get_drvdata(pdev->dev.parent);
512 if (!parent) {
513 dev_err(&pdev->dev, "No MFD driver data\n");
514 return -EINVAL;
515 }
516 bd_rtc = devm_kzalloc(&pdev->dev, sizeof(*bd_rtc), GFP_KERNEL);
517 if (!bd_rtc)
518 return -ENOMEM;
519
520 bd_rtc->parent = parent;
521 bd_rtc->dev = &pdev->dev;
522
523 switch (chip) {
524 case ROHM_CHIP_TYPE_BD70528:
525 irq_name = "bd70528-rtc-alm";
526 bd_rtc->has_rtc_timers = true;
527 bd_rtc->reg_time_start = BD70528_REG_RTC_START;
528 hour_reg = BD70528_REG_RTC_HOUR;
529 enable_main_irq = true;
530 rtc_ops = &bd70528_rtc_ops;
531 break;
532 case ROHM_CHIP_TYPE_BD71828:
533 irq_name = "bd71828-rtc-alm-0";
534 bd_rtc->reg_time_start = BD71828_REG_RTC_START;
535 hour_reg = BD71828_REG_RTC_HOUR;
536 rtc_ops = &bd71828_rtc_ops;
537 break;
538 default:
539 dev_err(&pdev->dev, "Unknown chip\n");
540 return -ENOENT;
541 }
542
543 irq = platform_get_irq_byname(pdev, irq_name);
544
545 if (irq < 0)
546 return irq;
547
548 platform_set_drvdata(pdev, bd_rtc);
549
550 ret = regmap_read(parent->regmap, hour_reg, &hr);
551
552 if (ret) {
553 dev_err(&pdev->dev, "Failed to reag RTC clock\n");
554 return ret;
555 }
556
557 if (!(hr & BD70528_MASK_RTC_HOUR_24H)) {
558 struct rtc_time t;
559
560 ret = rtc_ops->read_time(&pdev->dev, &t);
561
562 if (!ret)
563 ret = rtc_ops->set_time(&pdev->dev, &t);
564
565 if (ret) {
566 dev_err(&pdev->dev,
567 "Setting 24H clock for RTC failed\n");
568 return ret;
569 }
570 }
571
572 device_set_wakeup_capable(&pdev->dev, true);
573 device_wakeup_enable(&pdev->dev);
574
575 rtc = devm_rtc_allocate_device(&pdev->dev);
576 if (IS_ERR(rtc)) {
577 dev_err(&pdev->dev, "RTC device creation failed\n");
578 return PTR_ERR(rtc);
579 }
580
581 rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
582 rtc->range_max = RTC_TIMESTAMP_END_2099;
583 rtc->ops = rtc_ops;
584
585 /* Request alarm IRQ prior to registerig the RTC */
586 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, &alm_hndlr,
587 IRQF_ONESHOT, "bd70528-rtc", rtc);
588 if (ret)
589 return ret;
590
591 /*
592 * BD70528 irq controller is not touching the main mask register.
593 * So enable the RTC block interrupts at main level. We can just
594 * leave them enabled as irq-controller should disable irqs
595 * from sub-registers when IRQ is disabled or freed.
596 */
597 if (enable_main_irq) {
598 ret = regmap_update_bits(parent->regmap,
599 BD70528_REG_INT_MAIN_MASK,
600 BD70528_INT_RTC_MASK, 0);
601 if (ret) {
602 dev_err(&pdev->dev, "Failed to enable RTC interrupts\n");
603 return ret;
604 }
605 }
606
607 return devm_rtc_register_device(rtc);
608 }
609
610 static const struct platform_device_id bd718x7_rtc_id[] = {
611 { "bd70528-rtc", ROHM_CHIP_TYPE_BD70528 },
612 { "bd71828-rtc", ROHM_CHIP_TYPE_BD71828 },
613 { },
614 };
615 MODULE_DEVICE_TABLE(platform, bd718x7_rtc_id);
616
617 static struct platform_driver bd70528_rtc = {
618 .driver = {
619 .name = "bd70528-rtc"
620 },
621 .probe = bd70528_probe,
622 .id_table = bd718x7_rtc_id,
623 };
624
625 module_platform_driver(bd70528_rtc);
626
627 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
628 MODULE_DESCRIPTION("ROHM BD70528 and BD71828 PMIC RTC driver");
629 MODULE_LICENSE("GPL");
630 MODULE_ALIAS("platform:bd70528-rtc");