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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * RTC driver for the Micro Crystal RV8803
4 *
5 * Copyright (C) 2015 Micro Crystal SA
6 * Alexandre Belloni <alexandre.belloni@bootlin.com>
7 *
8 */
9
10#include <linux/bcd.h>
11#include <linux/bitops.h>
12#include <linux/bitfield.h>
13#include <linux/log2.h>
14#include <linux/i2c.h>
15#include <linux/interrupt.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/rtc.h>
20#include <linux/pm_wakeirq.h>
21
22#define RV8803_I2C_TRY_COUNT 4
23
24#define RV8803_SEC 0x00
25#define RV8803_MIN 0x01
26#define RV8803_HOUR 0x02
27#define RV8803_WEEK 0x03
28#define RV8803_DAY 0x04
29#define RV8803_MONTH 0x05
30#define RV8803_YEAR 0x06
31#define RV8803_RAM 0x07
32#define RV8803_ALARM_MIN 0x08
33#define RV8803_ALARM_HOUR 0x09
34#define RV8803_ALARM_WEEK_OR_DAY 0x0A
35#define RV8803_EXT 0x0D
36#define RV8803_FLAG 0x0E
37#define RV8803_CTRL 0x0F
38#define RV8803_OSC_OFFSET 0x2C
39
40#define RV8803_EXT_WADA BIT(6)
41
42#define RV8803_FLAG_V1F BIT(0)
43#define RV8803_FLAG_V2F BIT(1)
44#define RV8803_FLAG_AF BIT(3)
45#define RV8803_FLAG_TF BIT(4)
46#define RV8803_FLAG_UF BIT(5)
47
48#define RV8803_CTRL_RESET BIT(0)
49
50#define RV8803_CTRL_EIE BIT(2)
51#define RV8803_CTRL_AIE BIT(3)
52#define RV8803_CTRL_TIE BIT(4)
53#define RV8803_CTRL_UIE BIT(5)
54
55#define RX8803_CTRL_CSEL GENMASK(7, 6)
56
57#define RX8900_BACKUP_CTRL 0x18
58#define RX8900_FLAG_SWOFF BIT(2)
59#define RX8900_FLAG_VDETOFF BIT(3)
60
61enum rv8803_type {
62 rv_8803,
63 rx_8803,
64 rx_8804,
65 rx_8900
66};
67
68struct rv8803_data {
69 struct i2c_client *client;
70 struct rtc_device *rtc;
71 struct mutex flags_lock;
72 u8 ctrl;
73 u8 backup;
74 u8 alarm_invalid:1;
75 enum rv8803_type type;
76};
77
78static int rv8803_read_reg(const struct i2c_client *client, u8 reg)
79{
80 int try = RV8803_I2C_TRY_COUNT;
81 s32 ret;
82
83 /*
84 * There is a 61µs window during which the RTC does not acknowledge I2C
85 * transfers. In that case, ensure that there are multiple attempts.
86 */
87 do
88 ret = i2c_smbus_read_byte_data(client, reg);
89 while ((ret == -ENXIO || ret == -EIO) && --try);
90 if (ret < 0)
91 dev_err(&client->dev, "Unable to read register 0x%02x\n", reg);
92
93 return ret;
94}
95
96static int rv8803_read_regs(const struct i2c_client *client,
97 u8 reg, u8 count, u8 *values)
98{
99 int try = RV8803_I2C_TRY_COUNT;
100 s32 ret;
101
102 do
103 ret = i2c_smbus_read_i2c_block_data(client, reg, count, values);
104 while ((ret == -ENXIO || ret == -EIO) && --try);
105 if (ret != count) {
106 dev_err(&client->dev,
107 "Unable to read registers 0x%02x..0x%02x\n",
108 reg, reg + count - 1);
109 return ret < 0 ? ret : -EIO;
110 }
111
112 return 0;
113}
114
115static int rv8803_write_reg(const struct i2c_client *client, u8 reg, u8 value)
116{
117 int try = RV8803_I2C_TRY_COUNT;
118 s32 ret;
119
120 do
121 ret = i2c_smbus_write_byte_data(client, reg, value);
122 while ((ret == -ENXIO || ret == -EIO) && --try);
123 if (ret)
124 dev_err(&client->dev, "Unable to write register 0x%02x\n", reg);
125
126 return ret;
127}
128
129static int rv8803_write_regs(const struct i2c_client *client,
130 u8 reg, u8 count, const u8 *values)
131{
132 int try = RV8803_I2C_TRY_COUNT;
133 s32 ret;
134
135 do
136 ret = i2c_smbus_write_i2c_block_data(client, reg, count,
137 values);
138 while ((ret == -ENXIO || ret == -EIO) && --try);
139 if (ret)
140 dev_err(&client->dev,
141 "Unable to write registers 0x%02x..0x%02x\n",
142 reg, reg + count - 1);
143
144 return ret;
145}
146
147static int rv8803_regs_init(struct rv8803_data *rv8803)
148{
149 int ret;
150
151 ret = rv8803_write_reg(rv8803->client, RV8803_OSC_OFFSET, 0x00);
152 if (ret)
153 return ret;
154
155 ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
156 FIELD_PREP(RX8803_CTRL_CSEL, 1)); /* 2s */
157 if (ret)
158 return ret;
159
160 ret = rv8803_write_regs(rv8803->client, RV8803_ALARM_MIN, 3,
161 (u8[]){ 0, 0, 0 });
162 if (ret)
163 return ret;
164
165 return rv8803_write_reg(rv8803->client, RV8803_RAM, 0x00);
166}
167
168static int rv8803_regs_configure(struct rv8803_data *rv8803);
169
170static int rv8803_regs_reset(struct rv8803_data *rv8803, bool full)
171{
172 /*
173 * The RV-8803 resets all registers to POR defaults after voltage-loss,
174 * the Epson RTCs don't, so we manually reset the remainder here.
175 */
176 if (full || rv8803->type == rx_8803 || rv8803->type == rx_8900) {
177 int ret = rv8803_regs_init(rv8803);
178 if (ret)
179 return ret;
180 }
181
182 return rv8803_regs_configure(rv8803);
183}
184
185static irqreturn_t rv8803_handle_irq(int irq, void *dev_id)
186{
187 struct i2c_client *client = dev_id;
188 struct rv8803_data *rv8803 = i2c_get_clientdata(client);
189 unsigned long events = 0;
190 int flags;
191
192 mutex_lock(&rv8803->flags_lock);
193
194 flags = rv8803_read_reg(client, RV8803_FLAG);
195 if (flags <= 0) {
196 mutex_unlock(&rv8803->flags_lock);
197 return IRQ_NONE;
198 }
199
200 if (flags & RV8803_FLAG_V1F)
201 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
202
203 if (flags & RV8803_FLAG_V2F)
204 dev_warn(&client->dev, "Voltage low, data loss detected.\n");
205
206 if (flags & RV8803_FLAG_TF) {
207 flags &= ~RV8803_FLAG_TF;
208 rv8803->ctrl &= ~RV8803_CTRL_TIE;
209 events |= RTC_PF;
210 }
211
212 if (flags & RV8803_FLAG_AF) {
213 flags &= ~RV8803_FLAG_AF;
214 rv8803->ctrl &= ~RV8803_CTRL_AIE;
215 events |= RTC_AF;
216 }
217
218 if (flags & RV8803_FLAG_UF) {
219 flags &= ~RV8803_FLAG_UF;
220 rv8803->ctrl &= ~RV8803_CTRL_UIE;
221 events |= RTC_UF;
222 }
223
224 if (events) {
225 rtc_update_irq(rv8803->rtc, 1, events);
226 rv8803_write_reg(client, RV8803_FLAG, flags);
227 rv8803_write_reg(rv8803->client, RV8803_CTRL, rv8803->ctrl);
228 }
229
230 mutex_unlock(&rv8803->flags_lock);
231
232 return IRQ_HANDLED;
233}
234
235static int rv8803_get_time(struct device *dev, struct rtc_time *tm)
236{
237 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
238 u8 date1[7];
239 u8 date2[7];
240 u8 *date = date1;
241 int ret, flags;
242
243 if (rv8803->alarm_invalid) {
244 dev_warn(dev, "Corruption detected, data may be invalid.\n");
245 return -EINVAL;
246 }
247
248 flags = rv8803_read_reg(rv8803->client, RV8803_FLAG);
249 if (flags < 0)
250 return flags;
251
252 if (flags & RV8803_FLAG_V2F) {
253 dev_warn(dev, "Voltage low, data is invalid.\n");
254 return -EINVAL;
255 }
256
257 ret = rv8803_read_regs(rv8803->client, RV8803_SEC, 7, date);
258 if (ret)
259 return ret;
260
261 if ((date1[RV8803_SEC] & 0x7f) == bin2bcd(59)) {
262 ret = rv8803_read_regs(rv8803->client, RV8803_SEC, 7, date2);
263 if (ret)
264 return ret;
265
266 if ((date2[RV8803_SEC] & 0x7f) != bin2bcd(59))
267 date = date2;
268 }
269
270 tm->tm_sec = bcd2bin(date[RV8803_SEC] & 0x7f);
271 tm->tm_min = bcd2bin(date[RV8803_MIN] & 0x7f);
272 tm->tm_hour = bcd2bin(date[RV8803_HOUR] & 0x3f);
273 tm->tm_wday = ilog2(date[RV8803_WEEK] & 0x7f);
274 tm->tm_mday = bcd2bin(date[RV8803_DAY] & 0x3f);
275 tm->tm_mon = bcd2bin(date[RV8803_MONTH] & 0x1f) - 1;
276 tm->tm_year = bcd2bin(date[RV8803_YEAR]) + 100;
277
278 return 0;
279}
280
281static int rv8803_set_time(struct device *dev, struct rtc_time *tm)
282{
283 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
284 u8 date[7];
285 int ctrl, flags, ret;
286
287 ctrl = rv8803_read_reg(rv8803->client, RV8803_CTRL);
288 if (ctrl < 0)
289 return ctrl;
290
291 /* Stop the clock */
292 ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
293 ctrl | RV8803_CTRL_RESET);
294 if (ret)
295 return ret;
296
297 date[RV8803_SEC] = bin2bcd(tm->tm_sec);
298 date[RV8803_MIN] = bin2bcd(tm->tm_min);
299 date[RV8803_HOUR] = bin2bcd(tm->tm_hour);
300 date[RV8803_WEEK] = 1 << (tm->tm_wday);
301 date[RV8803_DAY] = bin2bcd(tm->tm_mday);
302 date[RV8803_MONTH] = bin2bcd(tm->tm_mon + 1);
303 date[RV8803_YEAR] = bin2bcd(tm->tm_year - 100);
304
305 ret = rv8803_write_regs(rv8803->client, RV8803_SEC, 7, date);
306 if (ret)
307 return ret;
308
309 /* Restart the clock */
310 ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
311 ctrl & ~RV8803_CTRL_RESET);
312 if (ret)
313 return ret;
314
315 mutex_lock(&rv8803->flags_lock);
316
317 flags = rv8803_read_reg(rv8803->client, RV8803_FLAG);
318 if (flags < 0) {
319 mutex_unlock(&rv8803->flags_lock);
320 return flags;
321 }
322
323 if ((flags & RV8803_FLAG_V2F) || rv8803->alarm_invalid) {
324 /*
325 * If we sense corruption in the alarm registers, but see no
326 * voltage loss flag, we can't rely on other registers having
327 * sensible values. Reset them fully.
328 */
329 ret = rv8803_regs_reset(rv8803, rv8803->alarm_invalid);
330 if (ret) {
331 mutex_unlock(&rv8803->flags_lock);
332 return ret;
333 }
334
335 rv8803->alarm_invalid = false;
336 }
337
338 ret = rv8803_write_reg(rv8803->client, RV8803_FLAG,
339 flags & ~(RV8803_FLAG_V1F | RV8803_FLAG_V2F));
340
341 mutex_unlock(&rv8803->flags_lock);
342
343 return ret;
344}
345
346static int rv8803_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
347{
348 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
349 struct i2c_client *client = rv8803->client;
350 u8 alarmvals[3];
351 int flags, ret;
352
353 ret = rv8803_read_regs(client, RV8803_ALARM_MIN, 3, alarmvals);
354 if (ret)
355 return ret;
356
357 flags = rv8803_read_reg(client, RV8803_FLAG);
358 if (flags < 0)
359 return flags;
360
361 alarmvals[0] &= 0x7f;
362 alarmvals[1] &= 0x3f;
363 alarmvals[2] &= 0x3f;
364
365 if (!bcd_is_valid(alarmvals[0]) ||
366 !bcd_is_valid(alarmvals[1]) ||
367 !bcd_is_valid(alarmvals[2]))
368 goto err_invalid;
369
370 alrm->time.tm_sec = 0;
371 alrm->time.tm_min = bcd2bin(alarmvals[0]);
372 alrm->time.tm_hour = bcd2bin(alarmvals[1]);
373 alrm->time.tm_mday = bcd2bin(alarmvals[2]);
374
375 alrm->enabled = !!(rv8803->ctrl & RV8803_CTRL_AIE);
376 alrm->pending = (flags & RV8803_FLAG_AF) && alrm->enabled;
377
378 if ((unsigned int)alrm->time.tm_mday > 31 ||
379 (unsigned int)alrm->time.tm_hour >= 24 ||
380 (unsigned int)alrm->time.tm_min >= 60)
381 goto err_invalid;
382
383 return 0;
384
385err_invalid:
386 rv8803->alarm_invalid = true;
387 return -EINVAL;
388}
389
390static int rv8803_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
391{
392 struct i2c_client *client = to_i2c_client(dev);
393 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
394 u8 alarmvals[3];
395 u8 ctrl[2];
396 int ret, err;
397
398 /* The alarm has no seconds, round up to nearest minute */
399 if (alrm->time.tm_sec) {
400 time64_t alarm_time = rtc_tm_to_time64(&alrm->time);
401
402 alarm_time += 60 - alrm->time.tm_sec;
403 rtc_time64_to_tm(alarm_time, &alrm->time);
404 }
405
406 mutex_lock(&rv8803->flags_lock);
407
408 ret = rv8803_read_regs(client, RV8803_FLAG, 2, ctrl);
409 if (ret) {
410 mutex_unlock(&rv8803->flags_lock);
411 return ret;
412 }
413
414 alarmvals[0] = bin2bcd(alrm->time.tm_min);
415 alarmvals[1] = bin2bcd(alrm->time.tm_hour);
416 alarmvals[2] = bin2bcd(alrm->time.tm_mday);
417
418 if (rv8803->ctrl & (RV8803_CTRL_AIE | RV8803_CTRL_UIE)) {
419 rv8803->ctrl &= ~(RV8803_CTRL_AIE | RV8803_CTRL_UIE);
420 err = rv8803_write_reg(rv8803->client, RV8803_CTRL,
421 rv8803->ctrl);
422 if (err) {
423 mutex_unlock(&rv8803->flags_lock);
424 return err;
425 }
426 }
427
428 ctrl[0] &= ~RV8803_FLAG_AF;
429 err = rv8803_write_reg(rv8803->client, RV8803_FLAG, ctrl[0]);
430 mutex_unlock(&rv8803->flags_lock);
431 if (err)
432 return err;
433
434 err = rv8803_write_regs(rv8803->client, RV8803_ALARM_MIN, 3, alarmvals);
435 if (err)
436 return err;
437
438 if (alrm->enabled) {
439 if (rv8803->rtc->uie_rtctimer.enabled)
440 rv8803->ctrl |= RV8803_CTRL_UIE;
441 if (rv8803->rtc->aie_timer.enabled)
442 rv8803->ctrl |= RV8803_CTRL_AIE;
443
444 err = rv8803_write_reg(rv8803->client, RV8803_CTRL,
445 rv8803->ctrl);
446 if (err)
447 return err;
448 }
449
450 return 0;
451}
452
453static int rv8803_alarm_irq_enable(struct device *dev, unsigned int enabled)
454{
455 struct i2c_client *client = to_i2c_client(dev);
456 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
457 int ctrl, flags, err;
458
459 ctrl = rv8803->ctrl;
460
461 if (enabled) {
462 if (rv8803->rtc->uie_rtctimer.enabled)
463 ctrl |= RV8803_CTRL_UIE;
464 if (rv8803->rtc->aie_timer.enabled)
465 ctrl |= RV8803_CTRL_AIE;
466 } else {
467 if (!rv8803->rtc->uie_rtctimer.enabled)
468 ctrl &= ~RV8803_CTRL_UIE;
469 if (!rv8803->rtc->aie_timer.enabled)
470 ctrl &= ~RV8803_CTRL_AIE;
471 }
472
473 mutex_lock(&rv8803->flags_lock);
474 flags = rv8803_read_reg(client, RV8803_FLAG);
475 if (flags < 0) {
476 mutex_unlock(&rv8803->flags_lock);
477 return flags;
478 }
479 flags &= ~(RV8803_FLAG_AF | RV8803_FLAG_UF);
480 err = rv8803_write_reg(client, RV8803_FLAG, flags);
481 mutex_unlock(&rv8803->flags_lock);
482 if (err)
483 return err;
484
485 if (ctrl != rv8803->ctrl) {
486 rv8803->ctrl = ctrl;
487 err = rv8803_write_reg(client, RV8803_CTRL, rv8803->ctrl);
488 if (err)
489 return err;
490 }
491
492 return 0;
493}
494
495static int rv8803_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
496{
497 struct i2c_client *client = to_i2c_client(dev);
498 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
499 unsigned int vl = 0;
500 int flags, ret = 0;
501
502 switch (cmd) {
503 case RTC_VL_READ:
504 flags = rv8803_read_reg(client, RV8803_FLAG);
505 if (flags < 0)
506 return flags;
507
508 if (flags & RV8803_FLAG_V1F) {
509 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
510 vl = RTC_VL_ACCURACY_LOW;
511 }
512
513 if (flags & RV8803_FLAG_V2F)
514 vl |= RTC_VL_DATA_INVALID;
515
516 return put_user(vl, (unsigned int __user *)arg);
517
518 case RTC_VL_CLR:
519 mutex_lock(&rv8803->flags_lock);
520 flags = rv8803_read_reg(client, RV8803_FLAG);
521 if (flags < 0) {
522 mutex_unlock(&rv8803->flags_lock);
523 return flags;
524 }
525
526 flags &= ~RV8803_FLAG_V1F;
527 ret = rv8803_write_reg(client, RV8803_FLAG, flags);
528 mutex_unlock(&rv8803->flags_lock);
529 if (ret)
530 return ret;
531
532 return 0;
533
534 default:
535 return -ENOIOCTLCMD;
536 }
537}
538
539static int rv8803_nvram_write(void *priv, unsigned int offset, void *val,
540 size_t bytes)
541{
542 return rv8803_write_reg(priv, RV8803_RAM, *(u8 *)val);
543}
544
545static int rv8803_nvram_read(void *priv, unsigned int offset,
546 void *val, size_t bytes)
547{
548 int ret;
549
550 ret = rv8803_read_reg(priv, RV8803_RAM);
551 if (ret < 0)
552 return ret;
553
554 *(u8 *)val = ret;
555
556 return 0;
557}
558
559static const struct rtc_class_ops rv8803_rtc_ops = {
560 .read_time = rv8803_get_time,
561 .set_time = rv8803_set_time,
562 .ioctl = rv8803_ioctl,
563 .read_alarm = rv8803_get_alarm,
564 .set_alarm = rv8803_set_alarm,
565 .alarm_irq_enable = rv8803_alarm_irq_enable,
566};
567
568static int rx8900_trickle_charger_init(struct rv8803_data *rv8803)
569{
570 struct i2c_client *client = rv8803->client;
571 struct device_node *node = client->dev.of_node;
572 int err;
573 u8 flags;
574
575 if (!node)
576 return 0;
577
578 if (rv8803->type != rx_8900)
579 return 0;
580
581 err = i2c_smbus_read_byte_data(rv8803->client, RX8900_BACKUP_CTRL);
582 if (err < 0)
583 return err;
584
585 flags = (u8)err;
586 flags &= ~(RX8900_FLAG_VDETOFF | RX8900_FLAG_SWOFF);
587 flags |= rv8803->backup;
588
589 return i2c_smbus_write_byte_data(rv8803->client, RX8900_BACKUP_CTRL,
590 flags);
591}
592
593/* configure registers with values different than the Power-On reset defaults */
594static int rv8803_regs_configure(struct rv8803_data *rv8803)
595{
596 int err;
597
598 err = rv8803_write_reg(rv8803->client, RV8803_EXT, RV8803_EXT_WADA);
599 if (err)
600 return err;
601
602 err = rx8900_trickle_charger_init(rv8803);
603 if (err) {
604 dev_err(&rv8803->client->dev, "failed to init charger\n");
605 return err;
606 }
607
608 return 0;
609}
610
611static int rv8803_resume(struct device *dev)
612{
613 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
614
615 if (rv8803->client->irq > 0 && device_may_wakeup(dev))
616 disable_irq_wake(rv8803->client->irq);
617
618 return 0;
619}
620
621static int rv8803_suspend(struct device *dev)
622{
623 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
624
625 if (rv8803->client->irq > 0 && device_may_wakeup(dev))
626 enable_irq_wake(rv8803->client->irq);
627
628 return 0;
629}
630
631static DEFINE_SIMPLE_DEV_PM_OPS(rv8803_pm_ops, rv8803_suspend, rv8803_resume);
632
633static const struct i2c_device_id rv8803_id[] = {
634 { "rv8803", rv_8803 },
635 { "rv8804", rx_8804 },
636 { "rx8803", rx_8803 },
637 { "rx8900", rx_8900 },
638 { }
639};
640MODULE_DEVICE_TABLE(i2c, rv8803_id);
641
642static int rv8803_probe(struct i2c_client *client)
643{
644 struct i2c_adapter *adapter = client->adapter;
645 struct rv8803_data *rv8803;
646 int err, flags;
647 struct nvmem_config nvmem_cfg = {
648 .name = "rv8803_nvram",
649 .word_size = 1,
650 .stride = 1,
651 .size = 1,
652 .reg_read = rv8803_nvram_read,
653 .reg_write = rv8803_nvram_write,
654 .priv = client,
655 };
656
657 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
658 I2C_FUNC_SMBUS_I2C_BLOCK)) {
659 dev_err(&adapter->dev, "doesn't support I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK\n");
660 return -EIO;
661 }
662
663 rv8803 = devm_kzalloc(&client->dev, sizeof(struct rv8803_data),
664 GFP_KERNEL);
665 if (!rv8803)
666 return -ENOMEM;
667
668 mutex_init(&rv8803->flags_lock);
669 rv8803->client = client;
670 if (client->dev.of_node) {
671 rv8803->type = (uintptr_t)of_device_get_match_data(&client->dev);
672 } else {
673 const struct i2c_device_id *id = i2c_match_id(rv8803_id, client);
674
675 rv8803->type = id->driver_data;
676 }
677 i2c_set_clientdata(client, rv8803);
678
679 flags = rv8803_read_reg(client, RV8803_FLAG);
680 if (flags < 0)
681 return flags;
682
683 if (flags & RV8803_FLAG_V1F)
684 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
685
686 if (flags & RV8803_FLAG_V2F)
687 dev_warn(&client->dev, "Voltage low, data loss detected.\n");
688
689 if (flags & RV8803_FLAG_AF)
690 dev_warn(&client->dev, "An alarm maybe have been missed.\n");
691
692 rv8803->rtc = devm_rtc_allocate_device(&client->dev);
693 if (IS_ERR(rv8803->rtc))
694 return PTR_ERR(rv8803->rtc);
695
696 if (client->irq > 0) {
697 unsigned long irqflags = IRQF_TRIGGER_LOW;
698
699 if (dev_fwnode(&client->dev))
700 irqflags = 0;
701
702 err = devm_request_threaded_irq(&client->dev, client->irq,
703 NULL, rv8803_handle_irq,
704 irqflags | IRQF_ONESHOT,
705 "rv8803", client);
706 if (err) {
707 dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
708 client->irq = 0;
709 } else {
710 device_init_wakeup(&client->dev, true);
711 err = dev_pm_set_wake_irq(&client->dev, client->irq);
712 if (err)
713 dev_err(&client->dev, "failed to set wake IRQ\n");
714 }
715 } else {
716 if (device_property_read_bool(&client->dev, "wakeup-source"))
717 device_init_wakeup(&client->dev, true);
718 else
719 clear_bit(RTC_FEATURE_ALARM, rv8803->rtc->features);
720 }
721
722 if (of_property_read_bool(client->dev.of_node, "epson,vdet-disable"))
723 rv8803->backup |= RX8900_FLAG_VDETOFF;
724
725 if (of_property_read_bool(client->dev.of_node, "trickle-diode-disable"))
726 rv8803->backup |= RX8900_FLAG_SWOFF;
727
728 err = rv8803_regs_configure(rv8803);
729 if (err)
730 return err;
731
732 rv8803->rtc->ops = &rv8803_rtc_ops;
733 rv8803->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
734 rv8803->rtc->range_max = RTC_TIMESTAMP_END_2099;
735 err = devm_rtc_register_device(rv8803->rtc);
736 if (err)
737 return err;
738
739 devm_rtc_nvmem_register(rv8803->rtc, &nvmem_cfg);
740
741 rv8803->rtc->max_user_freq = 1;
742
743 return 0;
744}
745
746static const __maybe_unused struct of_device_id rv8803_of_match[] = {
747 {
748 .compatible = "microcrystal,rv8803",
749 .data = (void *)rv_8803
750 },
751 {
752 .compatible = "epson,rx8803",
753 .data = (void *)rx_8803
754 },
755 {
756 .compatible = "epson,rx8804",
757 .data = (void *)rx_8804
758 },
759 {
760 .compatible = "epson,rx8900",
761 .data = (void *)rx_8900
762 },
763 { }
764};
765MODULE_DEVICE_TABLE(of, rv8803_of_match);
766
767static struct i2c_driver rv8803_driver = {
768 .driver = {
769 .name = "rtc-rv8803",
770 .of_match_table = of_match_ptr(rv8803_of_match),
771 .pm = &rv8803_pm_ops,
772 },
773 .probe = rv8803_probe,
774 .id_table = rv8803_id,
775};
776module_i2c_driver(rv8803_driver);
777
778MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
779MODULE_DESCRIPTION("Micro Crystal RV8803 RTC driver");
780MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * RTC driver for the Micro Crystal RV8803
4 *
5 * Copyright (C) 2015 Micro Crystal SA
6 * Alexandre Belloni <alexandre.belloni@bootlin.com>
7 *
8 */
9
10#include <linux/bcd.h>
11#include <linux/bitops.h>
12#include <linux/bitfield.h>
13#include <linux/log2.h>
14#include <linux/i2c.h>
15#include <linux/interrupt.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/of_device.h>
19#include <linux/rtc.h>
20
21#define RV8803_I2C_TRY_COUNT 4
22
23#define RV8803_SEC 0x00
24#define RV8803_MIN 0x01
25#define RV8803_HOUR 0x02
26#define RV8803_WEEK 0x03
27#define RV8803_DAY 0x04
28#define RV8803_MONTH 0x05
29#define RV8803_YEAR 0x06
30#define RV8803_RAM 0x07
31#define RV8803_ALARM_MIN 0x08
32#define RV8803_ALARM_HOUR 0x09
33#define RV8803_ALARM_WEEK_OR_DAY 0x0A
34#define RV8803_EXT 0x0D
35#define RV8803_FLAG 0x0E
36#define RV8803_CTRL 0x0F
37#define RV8803_OSC_OFFSET 0x2C
38
39#define RV8803_EXT_WADA BIT(6)
40
41#define RV8803_FLAG_V1F BIT(0)
42#define RV8803_FLAG_V2F BIT(1)
43#define RV8803_FLAG_AF BIT(3)
44#define RV8803_FLAG_TF BIT(4)
45#define RV8803_FLAG_UF BIT(5)
46
47#define RV8803_CTRL_RESET BIT(0)
48
49#define RV8803_CTRL_EIE BIT(2)
50#define RV8803_CTRL_AIE BIT(3)
51#define RV8803_CTRL_TIE BIT(4)
52#define RV8803_CTRL_UIE BIT(5)
53
54#define RX8803_CTRL_CSEL GENMASK(7, 6)
55
56#define RX8900_BACKUP_CTRL 0x18
57#define RX8900_FLAG_SWOFF BIT(2)
58#define RX8900_FLAG_VDETOFF BIT(3)
59
60enum rv8803_type {
61 rv_8803,
62 rx_8803,
63 rx_8804,
64 rx_8900
65};
66
67struct rv8803_data {
68 struct i2c_client *client;
69 struct rtc_device *rtc;
70 struct mutex flags_lock;
71 u8 ctrl;
72 u8 backup;
73 enum rv8803_type type;
74};
75
76static int rv8803_read_reg(const struct i2c_client *client, u8 reg)
77{
78 int try = RV8803_I2C_TRY_COUNT;
79 s32 ret;
80
81 /*
82 * There is a 61µs window during which the RTC does not acknowledge I2C
83 * transfers. In that case, ensure that there are multiple attempts.
84 */
85 do
86 ret = i2c_smbus_read_byte_data(client, reg);
87 while ((ret == -ENXIO || ret == -EIO) && --try);
88 if (ret < 0)
89 dev_err(&client->dev, "Unable to read register 0x%02x\n", reg);
90
91 return ret;
92}
93
94static int rv8803_read_regs(const struct i2c_client *client,
95 u8 reg, u8 count, u8 *values)
96{
97 int try = RV8803_I2C_TRY_COUNT;
98 s32 ret;
99
100 do
101 ret = i2c_smbus_read_i2c_block_data(client, reg, count, values);
102 while ((ret == -ENXIO || ret == -EIO) && --try);
103 if (ret != count) {
104 dev_err(&client->dev,
105 "Unable to read registers 0x%02x..0x%02x\n",
106 reg, reg + count - 1);
107 return ret < 0 ? ret : -EIO;
108 }
109
110 return 0;
111}
112
113static int rv8803_write_reg(const struct i2c_client *client, u8 reg, u8 value)
114{
115 int try = RV8803_I2C_TRY_COUNT;
116 s32 ret;
117
118 do
119 ret = i2c_smbus_write_byte_data(client, reg, value);
120 while ((ret == -ENXIO || ret == -EIO) && --try);
121 if (ret)
122 dev_err(&client->dev, "Unable to write register 0x%02x\n", reg);
123
124 return ret;
125}
126
127static int rv8803_write_regs(const struct i2c_client *client,
128 u8 reg, u8 count, const u8 *values)
129{
130 int try = RV8803_I2C_TRY_COUNT;
131 s32 ret;
132
133 do
134 ret = i2c_smbus_write_i2c_block_data(client, reg, count,
135 values);
136 while ((ret == -ENXIO || ret == -EIO) && --try);
137 if (ret)
138 dev_err(&client->dev,
139 "Unable to write registers 0x%02x..0x%02x\n",
140 reg, reg + count - 1);
141
142 return ret;
143}
144
145static int rv8803_regs_init(struct rv8803_data *rv8803)
146{
147 int ret;
148
149 ret = rv8803_write_reg(rv8803->client, RV8803_OSC_OFFSET, 0x00);
150 if (ret)
151 return ret;
152
153 ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
154 FIELD_PREP(RX8803_CTRL_CSEL, 1)); /* 2s */
155 if (ret)
156 return ret;
157
158 ret = rv8803_write_regs(rv8803->client, RV8803_ALARM_MIN, 3,
159 (u8[]){ 0, 0, 0 });
160 if (ret)
161 return ret;
162
163 return rv8803_write_reg(rv8803->client, RV8803_RAM, 0x00);
164}
165
166static int rv8803_regs_configure(struct rv8803_data *rv8803);
167
168static int rv8803_regs_reset(struct rv8803_data *rv8803)
169{
170 /*
171 * The RV-8803 resets all registers to POR defaults after voltage-loss,
172 * the Epson RTCs don't, so we manually reset the remainder here.
173 */
174 if (rv8803->type == rx_8803 || rv8803->type == rx_8900) {
175 int ret = rv8803_regs_init(rv8803);
176 if (ret)
177 return ret;
178 }
179
180 return rv8803_regs_configure(rv8803);
181}
182
183static irqreturn_t rv8803_handle_irq(int irq, void *dev_id)
184{
185 struct i2c_client *client = dev_id;
186 struct rv8803_data *rv8803 = i2c_get_clientdata(client);
187 unsigned long events = 0;
188 int flags;
189
190 mutex_lock(&rv8803->flags_lock);
191
192 flags = rv8803_read_reg(client, RV8803_FLAG);
193 if (flags <= 0) {
194 mutex_unlock(&rv8803->flags_lock);
195 return IRQ_NONE;
196 }
197
198 if (flags & RV8803_FLAG_V1F)
199 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
200
201 if (flags & RV8803_FLAG_V2F)
202 dev_warn(&client->dev, "Voltage low, data loss detected.\n");
203
204 if (flags & RV8803_FLAG_TF) {
205 flags &= ~RV8803_FLAG_TF;
206 rv8803->ctrl &= ~RV8803_CTRL_TIE;
207 events |= RTC_PF;
208 }
209
210 if (flags & RV8803_FLAG_AF) {
211 flags &= ~RV8803_FLAG_AF;
212 rv8803->ctrl &= ~RV8803_CTRL_AIE;
213 events |= RTC_AF;
214 }
215
216 if (flags & RV8803_FLAG_UF) {
217 flags &= ~RV8803_FLAG_UF;
218 rv8803->ctrl &= ~RV8803_CTRL_UIE;
219 events |= RTC_UF;
220 }
221
222 if (events) {
223 rtc_update_irq(rv8803->rtc, 1, events);
224 rv8803_write_reg(client, RV8803_FLAG, flags);
225 rv8803_write_reg(rv8803->client, RV8803_CTRL, rv8803->ctrl);
226 }
227
228 mutex_unlock(&rv8803->flags_lock);
229
230 return IRQ_HANDLED;
231}
232
233static int rv8803_get_time(struct device *dev, struct rtc_time *tm)
234{
235 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
236 u8 date1[7];
237 u8 date2[7];
238 u8 *date = date1;
239 int ret, flags;
240
241 flags = rv8803_read_reg(rv8803->client, RV8803_FLAG);
242 if (flags < 0)
243 return flags;
244
245 if (flags & RV8803_FLAG_V2F) {
246 dev_warn(dev, "Voltage low, data is invalid.\n");
247 return -EINVAL;
248 }
249
250 ret = rv8803_read_regs(rv8803->client, RV8803_SEC, 7, date);
251 if (ret)
252 return ret;
253
254 if ((date1[RV8803_SEC] & 0x7f) == bin2bcd(59)) {
255 ret = rv8803_read_regs(rv8803->client, RV8803_SEC, 7, date2);
256 if (ret)
257 return ret;
258
259 if ((date2[RV8803_SEC] & 0x7f) != bin2bcd(59))
260 date = date2;
261 }
262
263 tm->tm_sec = bcd2bin(date[RV8803_SEC] & 0x7f);
264 tm->tm_min = bcd2bin(date[RV8803_MIN] & 0x7f);
265 tm->tm_hour = bcd2bin(date[RV8803_HOUR] & 0x3f);
266 tm->tm_wday = ilog2(date[RV8803_WEEK] & 0x7f);
267 tm->tm_mday = bcd2bin(date[RV8803_DAY] & 0x3f);
268 tm->tm_mon = bcd2bin(date[RV8803_MONTH] & 0x1f) - 1;
269 tm->tm_year = bcd2bin(date[RV8803_YEAR]) + 100;
270
271 return 0;
272}
273
274static int rv8803_set_time(struct device *dev, struct rtc_time *tm)
275{
276 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
277 u8 date[7];
278 int ctrl, flags, ret;
279
280 ctrl = rv8803_read_reg(rv8803->client, RV8803_CTRL);
281 if (ctrl < 0)
282 return ctrl;
283
284 /* Stop the clock */
285 ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
286 ctrl | RV8803_CTRL_RESET);
287 if (ret)
288 return ret;
289
290 date[RV8803_SEC] = bin2bcd(tm->tm_sec);
291 date[RV8803_MIN] = bin2bcd(tm->tm_min);
292 date[RV8803_HOUR] = bin2bcd(tm->tm_hour);
293 date[RV8803_WEEK] = 1 << (tm->tm_wday);
294 date[RV8803_DAY] = bin2bcd(tm->tm_mday);
295 date[RV8803_MONTH] = bin2bcd(tm->tm_mon + 1);
296 date[RV8803_YEAR] = bin2bcd(tm->tm_year - 100);
297
298 ret = rv8803_write_regs(rv8803->client, RV8803_SEC, 7, date);
299 if (ret)
300 return ret;
301
302 /* Restart the clock */
303 ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
304 ctrl & ~RV8803_CTRL_RESET);
305 if (ret)
306 return ret;
307
308 mutex_lock(&rv8803->flags_lock);
309
310 flags = rv8803_read_reg(rv8803->client, RV8803_FLAG);
311 if (flags < 0) {
312 mutex_unlock(&rv8803->flags_lock);
313 return flags;
314 }
315
316 if (flags & RV8803_FLAG_V2F) {
317 ret = rv8803_regs_reset(rv8803);
318 if (ret) {
319 mutex_unlock(&rv8803->flags_lock);
320 return ret;
321 }
322 }
323
324 ret = rv8803_write_reg(rv8803->client, RV8803_FLAG,
325 flags & ~(RV8803_FLAG_V1F | RV8803_FLAG_V2F));
326
327 mutex_unlock(&rv8803->flags_lock);
328
329 return ret;
330}
331
332static int rv8803_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
333{
334 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
335 struct i2c_client *client = rv8803->client;
336 u8 alarmvals[3];
337 int flags, ret;
338
339 ret = rv8803_read_regs(client, RV8803_ALARM_MIN, 3, alarmvals);
340 if (ret)
341 return ret;
342
343 flags = rv8803_read_reg(client, RV8803_FLAG);
344 if (flags < 0)
345 return flags;
346
347 alrm->time.tm_sec = 0;
348 alrm->time.tm_min = bcd2bin(alarmvals[0] & 0x7f);
349 alrm->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
350 alrm->time.tm_mday = bcd2bin(alarmvals[2] & 0x3f);
351
352 alrm->enabled = !!(rv8803->ctrl & RV8803_CTRL_AIE);
353 alrm->pending = (flags & RV8803_FLAG_AF) && alrm->enabled;
354
355 return 0;
356}
357
358static int rv8803_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
359{
360 struct i2c_client *client = to_i2c_client(dev);
361 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
362 u8 alarmvals[3];
363 u8 ctrl[2];
364 int ret, err;
365
366 /* The alarm has no seconds, round up to nearest minute */
367 if (alrm->time.tm_sec) {
368 time64_t alarm_time = rtc_tm_to_time64(&alrm->time);
369
370 alarm_time += 60 - alrm->time.tm_sec;
371 rtc_time64_to_tm(alarm_time, &alrm->time);
372 }
373
374 mutex_lock(&rv8803->flags_lock);
375
376 ret = rv8803_read_regs(client, RV8803_FLAG, 2, ctrl);
377 if (ret) {
378 mutex_unlock(&rv8803->flags_lock);
379 return ret;
380 }
381
382 alarmvals[0] = bin2bcd(alrm->time.tm_min);
383 alarmvals[1] = bin2bcd(alrm->time.tm_hour);
384 alarmvals[2] = bin2bcd(alrm->time.tm_mday);
385
386 if (rv8803->ctrl & (RV8803_CTRL_AIE | RV8803_CTRL_UIE)) {
387 rv8803->ctrl &= ~(RV8803_CTRL_AIE | RV8803_CTRL_UIE);
388 err = rv8803_write_reg(rv8803->client, RV8803_CTRL,
389 rv8803->ctrl);
390 if (err) {
391 mutex_unlock(&rv8803->flags_lock);
392 return err;
393 }
394 }
395
396 ctrl[0] &= ~RV8803_FLAG_AF;
397 err = rv8803_write_reg(rv8803->client, RV8803_FLAG, ctrl[0]);
398 mutex_unlock(&rv8803->flags_lock);
399 if (err)
400 return err;
401
402 err = rv8803_write_regs(rv8803->client, RV8803_ALARM_MIN, 3, alarmvals);
403 if (err)
404 return err;
405
406 if (alrm->enabled) {
407 if (rv8803->rtc->uie_rtctimer.enabled)
408 rv8803->ctrl |= RV8803_CTRL_UIE;
409 if (rv8803->rtc->aie_timer.enabled)
410 rv8803->ctrl |= RV8803_CTRL_AIE;
411
412 err = rv8803_write_reg(rv8803->client, RV8803_CTRL,
413 rv8803->ctrl);
414 if (err)
415 return err;
416 }
417
418 return 0;
419}
420
421static int rv8803_alarm_irq_enable(struct device *dev, unsigned int enabled)
422{
423 struct i2c_client *client = to_i2c_client(dev);
424 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
425 int ctrl, flags, err;
426
427 ctrl = rv8803->ctrl;
428
429 if (enabled) {
430 if (rv8803->rtc->uie_rtctimer.enabled)
431 ctrl |= RV8803_CTRL_UIE;
432 if (rv8803->rtc->aie_timer.enabled)
433 ctrl |= RV8803_CTRL_AIE;
434 } else {
435 if (!rv8803->rtc->uie_rtctimer.enabled)
436 ctrl &= ~RV8803_CTRL_UIE;
437 if (!rv8803->rtc->aie_timer.enabled)
438 ctrl &= ~RV8803_CTRL_AIE;
439 }
440
441 mutex_lock(&rv8803->flags_lock);
442 flags = rv8803_read_reg(client, RV8803_FLAG);
443 if (flags < 0) {
444 mutex_unlock(&rv8803->flags_lock);
445 return flags;
446 }
447 flags &= ~(RV8803_FLAG_AF | RV8803_FLAG_UF);
448 err = rv8803_write_reg(client, RV8803_FLAG, flags);
449 mutex_unlock(&rv8803->flags_lock);
450 if (err)
451 return err;
452
453 if (ctrl != rv8803->ctrl) {
454 rv8803->ctrl = ctrl;
455 err = rv8803_write_reg(client, RV8803_CTRL, rv8803->ctrl);
456 if (err)
457 return err;
458 }
459
460 return 0;
461}
462
463static int rv8803_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
464{
465 struct i2c_client *client = to_i2c_client(dev);
466 struct rv8803_data *rv8803 = dev_get_drvdata(dev);
467 unsigned int vl = 0;
468 int flags, ret = 0;
469
470 switch (cmd) {
471 case RTC_VL_READ:
472 flags = rv8803_read_reg(client, RV8803_FLAG);
473 if (flags < 0)
474 return flags;
475
476 if (flags & RV8803_FLAG_V1F) {
477 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
478 vl = RTC_VL_ACCURACY_LOW;
479 }
480
481 if (flags & RV8803_FLAG_V2F)
482 vl |= RTC_VL_DATA_INVALID;
483
484 return put_user(vl, (unsigned int __user *)arg);
485
486 case RTC_VL_CLR:
487 mutex_lock(&rv8803->flags_lock);
488 flags = rv8803_read_reg(client, RV8803_FLAG);
489 if (flags < 0) {
490 mutex_unlock(&rv8803->flags_lock);
491 return flags;
492 }
493
494 flags &= ~RV8803_FLAG_V1F;
495 ret = rv8803_write_reg(client, RV8803_FLAG, flags);
496 mutex_unlock(&rv8803->flags_lock);
497 if (ret)
498 return ret;
499
500 return 0;
501
502 default:
503 return -ENOIOCTLCMD;
504 }
505}
506
507static int rv8803_nvram_write(void *priv, unsigned int offset, void *val,
508 size_t bytes)
509{
510 return rv8803_write_reg(priv, RV8803_RAM, *(u8 *)val);
511}
512
513static int rv8803_nvram_read(void *priv, unsigned int offset,
514 void *val, size_t bytes)
515{
516 int ret;
517
518 ret = rv8803_read_reg(priv, RV8803_RAM);
519 if (ret < 0)
520 return ret;
521
522 *(u8 *)val = ret;
523
524 return 0;
525}
526
527static const struct rtc_class_ops rv8803_rtc_ops = {
528 .read_time = rv8803_get_time,
529 .set_time = rv8803_set_time,
530 .ioctl = rv8803_ioctl,
531 .read_alarm = rv8803_get_alarm,
532 .set_alarm = rv8803_set_alarm,
533 .alarm_irq_enable = rv8803_alarm_irq_enable,
534};
535
536static int rx8900_trickle_charger_init(struct rv8803_data *rv8803)
537{
538 struct i2c_client *client = rv8803->client;
539 struct device_node *node = client->dev.of_node;
540 int err;
541 u8 flags;
542
543 if (!node)
544 return 0;
545
546 if (rv8803->type != rx_8900)
547 return 0;
548
549 err = i2c_smbus_read_byte_data(rv8803->client, RX8900_BACKUP_CTRL);
550 if (err < 0)
551 return err;
552
553 flags = (u8)err;
554 flags &= ~(RX8900_FLAG_VDETOFF | RX8900_FLAG_SWOFF);
555 flags |= rv8803->backup;
556
557 return i2c_smbus_write_byte_data(rv8803->client, RX8900_BACKUP_CTRL,
558 flags);
559}
560
561/* configure registers with values different than the Power-On reset defaults */
562static int rv8803_regs_configure(struct rv8803_data *rv8803)
563{
564 int err;
565
566 err = rv8803_write_reg(rv8803->client, RV8803_EXT, RV8803_EXT_WADA);
567 if (err)
568 return err;
569
570 err = rx8900_trickle_charger_init(rv8803);
571 if (err) {
572 dev_err(&rv8803->client->dev, "failed to init charger\n");
573 return err;
574 }
575
576 return 0;
577}
578
579static const struct i2c_device_id rv8803_id[] = {
580 { "rv8803", rv_8803 },
581 { "rv8804", rx_8804 },
582 { "rx8803", rx_8803 },
583 { "rx8900", rx_8900 },
584 { }
585};
586MODULE_DEVICE_TABLE(i2c, rv8803_id);
587
588static int rv8803_probe(struct i2c_client *client)
589{
590 struct i2c_adapter *adapter = client->adapter;
591 struct rv8803_data *rv8803;
592 int err, flags;
593 struct nvmem_config nvmem_cfg = {
594 .name = "rv8803_nvram",
595 .word_size = 1,
596 .stride = 1,
597 .size = 1,
598 .reg_read = rv8803_nvram_read,
599 .reg_write = rv8803_nvram_write,
600 .priv = client,
601 };
602
603 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
604 I2C_FUNC_SMBUS_I2C_BLOCK)) {
605 dev_err(&adapter->dev, "doesn't support I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK\n");
606 return -EIO;
607 }
608
609 rv8803 = devm_kzalloc(&client->dev, sizeof(struct rv8803_data),
610 GFP_KERNEL);
611 if (!rv8803)
612 return -ENOMEM;
613
614 mutex_init(&rv8803->flags_lock);
615 rv8803->client = client;
616 if (client->dev.of_node) {
617 rv8803->type = (enum rv8803_type)
618 of_device_get_match_data(&client->dev);
619 } else {
620 const struct i2c_device_id *id = i2c_match_id(rv8803_id, client);
621
622 rv8803->type = id->driver_data;
623 }
624 i2c_set_clientdata(client, rv8803);
625
626 flags = rv8803_read_reg(client, RV8803_FLAG);
627 if (flags < 0)
628 return flags;
629
630 if (flags & RV8803_FLAG_V1F)
631 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
632
633 if (flags & RV8803_FLAG_V2F)
634 dev_warn(&client->dev, "Voltage low, data loss detected.\n");
635
636 if (flags & RV8803_FLAG_AF)
637 dev_warn(&client->dev, "An alarm maybe have been missed.\n");
638
639 rv8803->rtc = devm_rtc_allocate_device(&client->dev);
640 if (IS_ERR(rv8803->rtc))
641 return PTR_ERR(rv8803->rtc);
642
643 if (client->irq > 0) {
644 err = devm_request_threaded_irq(&client->dev, client->irq,
645 NULL, rv8803_handle_irq,
646 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
647 "rv8803", client);
648 if (err) {
649 dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
650 client->irq = 0;
651 }
652 }
653 if (!client->irq)
654 clear_bit(RTC_FEATURE_ALARM, rv8803->rtc->features);
655
656 if (of_property_read_bool(client->dev.of_node, "epson,vdet-disable"))
657 rv8803->backup |= RX8900_FLAG_VDETOFF;
658
659 if (of_property_read_bool(client->dev.of_node, "trickle-diode-disable"))
660 rv8803->backup |= RX8900_FLAG_SWOFF;
661
662 err = rv8803_regs_configure(rv8803);
663 if (err)
664 return err;
665
666 rv8803->rtc->ops = &rv8803_rtc_ops;
667 rv8803->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
668 rv8803->rtc->range_max = RTC_TIMESTAMP_END_2099;
669 err = devm_rtc_register_device(rv8803->rtc);
670 if (err)
671 return err;
672
673 devm_rtc_nvmem_register(rv8803->rtc, &nvmem_cfg);
674
675 rv8803->rtc->max_user_freq = 1;
676
677 return 0;
678}
679
680static const __maybe_unused struct of_device_id rv8803_of_match[] = {
681 {
682 .compatible = "microcrystal,rv8803",
683 .data = (void *)rv_8803
684 },
685 {
686 .compatible = "epson,rx8803",
687 .data = (void *)rx_8803
688 },
689 {
690 .compatible = "epson,rx8804",
691 .data = (void *)rx_8804
692 },
693 {
694 .compatible = "epson,rx8900",
695 .data = (void *)rx_8900
696 },
697 { }
698};
699MODULE_DEVICE_TABLE(of, rv8803_of_match);
700
701static struct i2c_driver rv8803_driver = {
702 .driver = {
703 .name = "rtc-rv8803",
704 .of_match_table = of_match_ptr(rv8803_of_match),
705 },
706 .probe_new = rv8803_probe,
707 .id_table = rv8803_id,
708};
709module_i2c_driver(rv8803_driver);
710
711MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
712MODULE_DESCRIPTION("Micro Crystal RV8803 RTC driver");
713MODULE_LICENSE("GPL v2");