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

source code of linux/drivers/rtc/rtc-rv8803.c