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1/*
2 * RTC client/driver for the Maxim/Dallas DS3232/DS3234 Real-Time Clock
3 *
4 * Copyright (C) 2009-2011 Freescale Semiconductor.
5 * Author: Jack Lan <jack.lan@freescale.com>
6 * Copyright (C) 2008 MIMOMax Wireless Ltd.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 */
13
14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/interrupt.h>
19#include <linux/i2c.h>
20#include <linux/spi/spi.h>
21#include <linux/rtc.h>
22#include <linux/bcd.h>
23#include <linux/slab.h>
24#include <linux/regmap.h>
25
26#define DS3232_REG_SECONDS 0x00
27#define DS3232_REG_MINUTES 0x01
28#define DS3232_REG_HOURS 0x02
29#define DS3232_REG_AMPM 0x02
30#define DS3232_REG_DAY 0x03
31#define DS3232_REG_DATE 0x04
32#define DS3232_REG_MONTH 0x05
33#define DS3232_REG_CENTURY 0x05
34#define DS3232_REG_YEAR 0x06
35#define DS3232_REG_ALARM1 0x07 /* Alarm 1 BASE */
36#define DS3232_REG_ALARM2 0x0B /* Alarm 2 BASE */
37#define DS3232_REG_CR 0x0E /* Control register */
38# define DS3232_REG_CR_nEOSC 0x80
39# define DS3232_REG_CR_INTCN 0x04
40# define DS3232_REG_CR_A2IE 0x02
41# define DS3232_REG_CR_A1IE 0x01
42
43#define DS3232_REG_SR 0x0F /* control/status register */
44# define DS3232_REG_SR_OSF 0x80
45# define DS3232_REG_SR_BSY 0x04
46# define DS3232_REG_SR_A2F 0x02
47# define DS3232_REG_SR_A1F 0x01
48
49struct ds3232 {
50 struct device *dev;
51 struct regmap *regmap;
52 int irq;
53 struct rtc_device *rtc;
54
55 bool suspended;
56};
57
58static int ds3232_check_rtc_status(struct device *dev)
59{
60 struct ds3232 *ds3232 = dev_get_drvdata(dev);
61 int ret = 0;
62 int control, stat;
63
64 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
65 if (ret)
66 return ret;
67
68 if (stat & DS3232_REG_SR_OSF)
69 dev_warn(dev,
70 "oscillator discontinuity flagged, "
71 "time unreliable\n");
72
73 stat &= ~(DS3232_REG_SR_OSF | DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
74
75 ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
76 if (ret)
77 return ret;
78
79 /* If the alarm is pending, clear it before requesting
80 * the interrupt, so an interrupt event isn't reported
81 * before everything is initialized.
82 */
83
84 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
85 if (ret)
86 return ret;
87
88 control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
89 control |= DS3232_REG_CR_INTCN;
90
91 return regmap_write(ds3232->regmap, DS3232_REG_CR, control);
92}
93
94static int ds3232_read_time(struct device *dev, struct rtc_time *time)
95{
96 struct ds3232 *ds3232 = dev_get_drvdata(dev);
97 int ret;
98 u8 buf[7];
99 unsigned int year, month, day, hour, minute, second;
100 unsigned int week, twelve_hr, am_pm;
101 unsigned int century, add_century = 0;
102
103 ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
104 if (ret)
105 return ret;
106
107 second = buf[0];
108 minute = buf[1];
109 hour = buf[2];
110 week = buf[3];
111 day = buf[4];
112 month = buf[5];
113 year = buf[6];
114
115 /* Extract additional information for AM/PM and century */
116
117 twelve_hr = hour & 0x40;
118 am_pm = hour & 0x20;
119 century = month & 0x80;
120
121 /* Write to rtc_time structure */
122
123 time->tm_sec = bcd2bin(second);
124 time->tm_min = bcd2bin(minute);
125 if (twelve_hr) {
126 /* Convert to 24 hr */
127 if (am_pm)
128 time->tm_hour = bcd2bin(hour & 0x1F) + 12;
129 else
130 time->tm_hour = bcd2bin(hour & 0x1F);
131 } else {
132 time->tm_hour = bcd2bin(hour);
133 }
134
135 /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
136 time->tm_wday = bcd2bin(week) - 1;
137 time->tm_mday = bcd2bin(day);
138 /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
139 time->tm_mon = bcd2bin(month & 0x7F) - 1;
140 if (century)
141 add_century = 100;
142
143 time->tm_year = bcd2bin(year) + add_century;
144
145 return rtc_valid_tm(time);
146}
147
148static int ds3232_set_time(struct device *dev, struct rtc_time *time)
149{
150 struct ds3232 *ds3232 = dev_get_drvdata(dev);
151 u8 buf[7];
152
153 /* Extract time from rtc_time and load into ds3232*/
154
155 buf[0] = bin2bcd(time->tm_sec);
156 buf[1] = bin2bcd(time->tm_min);
157 buf[2] = bin2bcd(time->tm_hour);
158 /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
159 buf[3] = bin2bcd(time->tm_wday + 1);
160 buf[4] = bin2bcd(time->tm_mday); /* Date */
161 /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
162 buf[5] = bin2bcd(time->tm_mon + 1);
163 if (time->tm_year >= 100) {
164 buf[5] |= 0x80;
165 buf[6] = bin2bcd(time->tm_year - 100);
166 } else {
167 buf[6] = bin2bcd(time->tm_year);
168 }
169
170 return regmap_bulk_write(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
171}
172
173/*
174 * DS3232 has two alarm, we only use alarm1
175 * According to linux specification, only support one-shot alarm
176 * no periodic alarm mode
177 */
178static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
179{
180 struct ds3232 *ds3232 = dev_get_drvdata(dev);
181 int control, stat;
182 int ret;
183 u8 buf[4];
184
185 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
186 if (ret)
187 goto out;
188 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
189 if (ret)
190 goto out;
191 ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
192 if (ret)
193 goto out;
194
195 alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
196 alarm->time.tm_min = bcd2bin(buf[1] & 0x7F);
197 alarm->time.tm_hour = bcd2bin(buf[2] & 0x7F);
198 alarm->time.tm_mday = bcd2bin(buf[3] & 0x7F);
199
200 alarm->time.tm_mon = -1;
201 alarm->time.tm_year = -1;
202 alarm->time.tm_wday = -1;
203 alarm->time.tm_yday = -1;
204 alarm->time.tm_isdst = -1;
205
206 alarm->enabled = !!(control & DS3232_REG_CR_A1IE);
207 alarm->pending = !!(stat & DS3232_REG_SR_A1F);
208
209 ret = 0;
210out:
211 return ret;
212}
213
214/*
215 * linux rtc-module does not support wday alarm
216 * and only 24h time mode supported indeed
217 */
218static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
219{
220 struct ds3232 *ds3232 = dev_get_drvdata(dev);
221 int control, stat;
222 int ret;
223 u8 buf[4];
224
225 if (ds3232->irq <= 0)
226 return -EINVAL;
227
228 buf[0] = bin2bcd(alarm->time.tm_sec);
229 buf[1] = bin2bcd(alarm->time.tm_min);
230 buf[2] = bin2bcd(alarm->time.tm_hour);
231 buf[3] = bin2bcd(alarm->time.tm_mday);
232
233 /* clear alarm interrupt enable bit */
234 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
235 if (ret)
236 goto out;
237 control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
238 ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
239 if (ret)
240 goto out;
241
242 /* clear any pending alarm flag */
243 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
244 if (ret)
245 goto out;
246 stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
247 ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
248 if (ret)
249 goto out;
250
251 ret = regmap_bulk_write(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
252 if (ret)
253 goto out;
254
255 if (alarm->enabled) {
256 control |= DS3232_REG_CR_A1IE;
257 ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
258 }
259out:
260 return ret;
261}
262
263static int ds3232_update_alarm(struct device *dev, unsigned int enabled)
264{
265 struct ds3232 *ds3232 = dev_get_drvdata(dev);
266 int control;
267 int ret;
268
269 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
270 if (ret)
271 return ret;
272
273 if (enabled)
274 /* enable alarm1 interrupt */
275 control |= DS3232_REG_CR_A1IE;
276 else
277 /* disable alarm1 interrupt */
278 control &= ~(DS3232_REG_CR_A1IE);
279 ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
280
281 return ret;
282}
283
284static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled)
285{
286 struct ds3232 *ds3232 = dev_get_drvdata(dev);
287
288 if (ds3232->irq <= 0)
289 return -EINVAL;
290
291 return ds3232_update_alarm(dev, enabled);
292}
293
294static irqreturn_t ds3232_irq(int irq, void *dev_id)
295{
296 struct device *dev = dev_id;
297 struct ds3232 *ds3232 = dev_get_drvdata(dev);
298 struct mutex *lock = &ds3232->rtc->ops_lock;
299 int ret;
300 int stat, control;
301
302 mutex_lock(lock);
303
304 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
305 if (ret)
306 goto unlock;
307
308 if (stat & DS3232_REG_SR_A1F) {
309 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
310 if (ret) {
311 dev_warn(ds3232->dev,
312 "Read Control Register error %d\n", ret);
313 } else {
314 /* disable alarm1 interrupt */
315 control &= ~(DS3232_REG_CR_A1IE);
316 ret = regmap_write(ds3232->regmap, DS3232_REG_CR,
317 control);
318 if (ret) {
319 dev_warn(ds3232->dev,
320 "Write Control Register error %d\n",
321 ret);
322 goto unlock;
323 }
324
325 /* clear the alarm pend flag */
326 stat &= ~DS3232_REG_SR_A1F;
327 ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
328 if (ret) {
329 dev_warn(ds3232->dev,
330 "Write Status Register error %d\n",
331 ret);
332 goto unlock;
333 }
334
335 rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
336 }
337 }
338
339unlock:
340 mutex_unlock(lock);
341
342 return IRQ_HANDLED;
343}
344
345static const struct rtc_class_ops ds3232_rtc_ops = {
346 .read_time = ds3232_read_time,
347 .set_time = ds3232_set_time,
348 .read_alarm = ds3232_read_alarm,
349 .set_alarm = ds3232_set_alarm,
350 .alarm_irq_enable = ds3232_alarm_irq_enable,
351};
352
353static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
354 const char *name)
355{
356 struct ds3232 *ds3232;
357 int ret;
358
359 ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL);
360 if (!ds3232)
361 return -ENOMEM;
362
363 ds3232->regmap = regmap;
364 ds3232->irq = irq;
365 ds3232->dev = dev;
366 dev_set_drvdata(dev, ds3232);
367
368 ret = ds3232_check_rtc_status(dev);
369 if (ret)
370 return ret;
371
372 if (ds3232->irq > 0) {
373 ret = devm_request_threaded_irq(dev, ds3232->irq, NULL,
374 ds3232_irq,
375 IRQF_SHARED | IRQF_ONESHOT,
376 name, dev);
377 if (ret) {
378 ds3232->irq = 0;
379 dev_err(dev, "unable to request IRQ\n");
380 } else
381 device_init_wakeup(dev, 1);
382 }
383 ds3232->rtc = devm_rtc_device_register(dev, name, &ds3232_rtc_ops,
384 THIS_MODULE);
385
386 return PTR_ERR_OR_ZERO(ds3232->rtc);
387}
388
389#ifdef CONFIG_PM_SLEEP
390static int ds3232_suspend(struct device *dev)
391{
392 struct ds3232 *ds3232 = dev_get_drvdata(dev);
393
394 if (device_may_wakeup(dev)) {
395 if (enable_irq_wake(ds3232->irq))
396 dev_warn_once(dev, "Cannot set wakeup source\n");
397 }
398
399 return 0;
400}
401
402static int ds3232_resume(struct device *dev)
403{
404 struct ds3232 *ds3232 = dev_get_drvdata(dev);
405
406 if (device_may_wakeup(dev))
407 disable_irq_wake(ds3232->irq);
408
409 return 0;
410}
411#endif
412
413static const struct dev_pm_ops ds3232_pm_ops = {
414 SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
415};
416
417#if IS_ENABLED(CONFIG_I2C)
418
419static int ds3232_i2c_probe(struct i2c_client *client,
420 const struct i2c_device_id *id)
421{
422 struct regmap *regmap;
423 static const struct regmap_config config = {
424 .reg_bits = 8,
425 .val_bits = 8,
426 };
427
428 regmap = devm_regmap_init_i2c(client, &config);
429 if (IS_ERR(regmap)) {
430 dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
431 __func__, PTR_ERR(regmap));
432 return PTR_ERR(regmap);
433 }
434
435 return ds3232_probe(&client->dev, regmap, client->irq, client->name);
436}
437
438static const struct i2c_device_id ds3232_id[] = {
439 { "ds3232", 0 },
440 { }
441};
442MODULE_DEVICE_TABLE(i2c, ds3232_id);
443
444static struct i2c_driver ds3232_driver = {
445 .driver = {
446 .name = "rtc-ds3232",
447 .pm = &ds3232_pm_ops,
448 },
449 .probe = ds3232_i2c_probe,
450 .id_table = ds3232_id,
451};
452
453static int ds3232_register_driver(void)
454{
455 return i2c_add_driver(&ds3232_driver);
456}
457
458static void ds3232_unregister_driver(void)
459{
460 i2c_del_driver(&ds3232_driver);
461}
462
463#else
464
465static int ds3232_register_driver(void)
466{
467 return 0;
468}
469
470static void ds3232_unregister_driver(void)
471{
472}
473
474#endif
475
476#if IS_ENABLED(CONFIG_SPI_MASTER)
477
478static int ds3234_probe(struct spi_device *spi)
479{
480 int res;
481 unsigned int tmp;
482 static const struct regmap_config config = {
483 .reg_bits = 8,
484 .val_bits = 8,
485 .write_flag_mask = 0x80,
486 };
487 struct regmap *regmap;
488
489 regmap = devm_regmap_init_spi(spi, &config);
490 if (IS_ERR(regmap)) {
491 dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
492 __func__, PTR_ERR(regmap));
493 return PTR_ERR(regmap);
494 }
495
496 spi->mode = SPI_MODE_3;
497 spi->bits_per_word = 8;
498 spi_setup(spi);
499
500 res = regmap_read(regmap, DS3232_REG_SECONDS, &tmp);
501 if (res)
502 return res;
503
504 /* Control settings
505 *
506 * CONTROL_REG
507 * BIT 7 6 5 4 3 2 1 0
508 * EOSC BBSQW CONV RS2 RS1 INTCN A2IE A1IE
509 *
510 * 0 0 0 1 1 1 0 0
511 *
512 * CONTROL_STAT_REG
513 * BIT 7 6 5 4 3 2 1 0
514 * OSF BB32kHz CRATE1 CRATE0 EN32kHz BSY A2F A1F
515 *
516 * 1 0 0 0 1 0 0 0
517 */
518 res = regmap_read(regmap, DS3232_REG_CR, &tmp);
519 if (res)
520 return res;
521 res = regmap_write(regmap, DS3232_REG_CR, tmp & 0x1c);
522 if (res)
523 return res;
524
525 res = regmap_read(regmap, DS3232_REG_SR, &tmp);
526 if (res)
527 return res;
528 res = regmap_write(regmap, DS3232_REG_SR, tmp & 0x88);
529 if (res)
530 return res;
531
532 /* Print our settings */
533 res = regmap_read(regmap, DS3232_REG_CR, &tmp);
534 if (res)
535 return res;
536 dev_info(&spi->dev, "Control Reg: 0x%02x\n", tmp);
537
538 res = regmap_read(regmap, DS3232_REG_SR, &tmp);
539 if (res)
540 return res;
541 dev_info(&spi->dev, "Ctrl/Stat Reg: 0x%02x\n", tmp);
542
543 return ds3232_probe(&spi->dev, regmap, spi->irq, "ds3234");
544}
545
546static struct spi_driver ds3234_driver = {
547 .driver = {
548 .name = "ds3234",
549 },
550 .probe = ds3234_probe,
551};
552
553static int ds3234_register_driver(void)
554{
555 return spi_register_driver(&ds3234_driver);
556}
557
558static void ds3234_unregister_driver(void)
559{
560 spi_unregister_driver(&ds3234_driver);
561}
562
563#else
564
565static int ds3234_register_driver(void)
566{
567 return 0;
568}
569
570static void ds3234_unregister_driver(void)
571{
572}
573
574#endif
575
576static int __init ds323x_init(void)
577{
578 int ret;
579
580 ret = ds3232_register_driver();
581 if (ret) {
582 pr_err("Failed to register ds3232 driver: %d\n", ret);
583 return ret;
584 }
585
586 ret = ds3234_register_driver();
587 if (ret) {
588 pr_err("Failed to register ds3234 driver: %d\n", ret);
589 ds3232_unregister_driver();
590 }
591
592 return ret;
593}
594module_init(ds323x_init)
595
596static void __exit ds323x_exit(void)
597{
598 ds3234_unregister_driver();
599 ds3232_unregister_driver();
600}
601module_exit(ds323x_exit)
602
603MODULE_AUTHOR("Srikanth Srinivasan <srikanth.srinivasan@freescale.com>");
604MODULE_AUTHOR("Dennis Aberilla <denzzzhome@yahoo.com>");
605MODULE_DESCRIPTION("Maxim/Dallas DS3232/DS3234 RTC Driver");
606MODULE_LICENSE("GPL");
607MODULE_ALIAS("spi:ds3234");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * RTC client/driver for the Maxim/Dallas DS3232/DS3234 Real-Time Clock
4 *
5 * Copyright (C) 2009-2011 Freescale Semiconductor.
6 * Author: Jack Lan <jack.lan@freescale.com>
7 * Copyright (C) 2008 MIMOMax Wireless Ltd.
8 */
9
10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/interrupt.h>
15#include <linux/i2c.h>
16#include <linux/spi/spi.h>
17#include <linux/rtc.h>
18#include <linux/bcd.h>
19#include <linux/slab.h>
20#include <linux/regmap.h>
21#include <linux/hwmon.h>
22
23#define DS3232_REG_SECONDS 0x00
24#define DS3232_REG_MINUTES 0x01
25#define DS3232_REG_HOURS 0x02
26#define DS3232_REG_AMPM 0x02
27#define DS3232_REG_DAY 0x03
28#define DS3232_REG_DATE 0x04
29#define DS3232_REG_MONTH 0x05
30#define DS3232_REG_CENTURY 0x05
31#define DS3232_REG_YEAR 0x06
32#define DS3232_REG_ALARM1 0x07 /* Alarm 1 BASE */
33#define DS3232_REG_ALARM2 0x0B /* Alarm 2 BASE */
34#define DS3232_REG_CR 0x0E /* Control register */
35# define DS3232_REG_CR_nEOSC 0x80
36# define DS3232_REG_CR_INTCN 0x04
37# define DS3232_REG_CR_A2IE 0x02
38# define DS3232_REG_CR_A1IE 0x01
39
40#define DS3232_REG_SR 0x0F /* control/status register */
41# define DS3232_REG_SR_OSF 0x80
42# define DS3232_REG_SR_BSY 0x04
43# define DS3232_REG_SR_A2F 0x02
44# define DS3232_REG_SR_A1F 0x01
45
46#define DS3232_REG_TEMPERATURE 0x11
47#define DS3232_REG_SRAM_START 0x14
48#define DS3232_REG_SRAM_END 0xFF
49
50#define DS3232_REG_SRAM_SIZE 236
51
52struct ds3232 {
53 struct device *dev;
54 struct regmap *regmap;
55 int irq;
56 struct rtc_device *rtc;
57
58 bool suspended;
59};
60
61static int ds3232_check_rtc_status(struct device *dev)
62{
63 struct ds3232 *ds3232 = dev_get_drvdata(dev);
64 int ret = 0;
65 int control, stat;
66
67 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
68 if (ret)
69 return ret;
70
71 if (stat & DS3232_REG_SR_OSF)
72 dev_warn(dev,
73 "oscillator discontinuity flagged, "
74 "time unreliable\n");
75
76 stat &= ~(DS3232_REG_SR_OSF | DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
77
78 ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
79 if (ret)
80 return ret;
81
82 /* If the alarm is pending, clear it before requesting
83 * the interrupt, so an interrupt event isn't reported
84 * before everything is initialized.
85 */
86
87 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
88 if (ret)
89 return ret;
90
91 control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
92 control |= DS3232_REG_CR_INTCN;
93
94 return regmap_write(ds3232->regmap, DS3232_REG_CR, control);
95}
96
97static int ds3232_read_time(struct device *dev, struct rtc_time *time)
98{
99 struct ds3232 *ds3232 = dev_get_drvdata(dev);
100 int ret;
101 u8 buf[7];
102 unsigned int year, month, day, hour, minute, second;
103 unsigned int week, twelve_hr, am_pm;
104 unsigned int century, add_century = 0;
105
106 ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
107 if (ret)
108 return ret;
109
110 second = buf[0];
111 minute = buf[1];
112 hour = buf[2];
113 week = buf[3];
114 day = buf[4];
115 month = buf[5];
116 year = buf[6];
117
118 /* Extract additional information for AM/PM and century */
119
120 twelve_hr = hour & 0x40;
121 am_pm = hour & 0x20;
122 century = month & 0x80;
123
124 /* Write to rtc_time structure */
125
126 time->tm_sec = bcd2bin(second);
127 time->tm_min = bcd2bin(minute);
128 if (twelve_hr) {
129 /* Convert to 24 hr */
130 if (am_pm)
131 time->tm_hour = bcd2bin(hour & 0x1F) + 12;
132 else
133 time->tm_hour = bcd2bin(hour & 0x1F);
134 } else {
135 time->tm_hour = bcd2bin(hour);
136 }
137
138 /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
139 time->tm_wday = bcd2bin(week) - 1;
140 time->tm_mday = bcd2bin(day);
141 /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
142 time->tm_mon = bcd2bin(month & 0x7F) - 1;
143 if (century)
144 add_century = 100;
145
146 time->tm_year = bcd2bin(year) + add_century;
147
148 return 0;
149}
150
151static int ds3232_set_time(struct device *dev, struct rtc_time *time)
152{
153 struct ds3232 *ds3232 = dev_get_drvdata(dev);
154 u8 buf[7];
155
156 /* Extract time from rtc_time and load into ds3232*/
157
158 buf[0] = bin2bcd(time->tm_sec);
159 buf[1] = bin2bcd(time->tm_min);
160 buf[2] = bin2bcd(time->tm_hour);
161 /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
162 buf[3] = bin2bcd(time->tm_wday + 1);
163 buf[4] = bin2bcd(time->tm_mday); /* Date */
164 /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
165 buf[5] = bin2bcd(time->tm_mon + 1);
166 if (time->tm_year >= 100) {
167 buf[5] |= 0x80;
168 buf[6] = bin2bcd(time->tm_year - 100);
169 } else {
170 buf[6] = bin2bcd(time->tm_year);
171 }
172
173 return regmap_bulk_write(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
174}
175
176/*
177 * DS3232 has two alarm, we only use alarm1
178 * According to linux specification, only support one-shot alarm
179 * no periodic alarm mode
180 */
181static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
182{
183 struct ds3232 *ds3232 = dev_get_drvdata(dev);
184 int control, stat;
185 int ret;
186 u8 buf[4];
187
188 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
189 if (ret)
190 goto out;
191 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
192 if (ret)
193 goto out;
194 ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
195 if (ret)
196 goto out;
197
198 alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
199 alarm->time.tm_min = bcd2bin(buf[1] & 0x7F);
200 alarm->time.tm_hour = bcd2bin(buf[2] & 0x7F);
201 alarm->time.tm_mday = bcd2bin(buf[3] & 0x7F);
202
203 alarm->enabled = !!(control & DS3232_REG_CR_A1IE);
204 alarm->pending = !!(stat & DS3232_REG_SR_A1F);
205
206 ret = 0;
207out:
208 return ret;
209}
210
211/*
212 * linux rtc-module does not support wday alarm
213 * and only 24h time mode supported indeed
214 */
215static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
216{
217 struct ds3232 *ds3232 = dev_get_drvdata(dev);
218 int control, stat;
219 int ret;
220 u8 buf[4];
221
222 if (ds3232->irq <= 0)
223 return -EINVAL;
224
225 buf[0] = bin2bcd(alarm->time.tm_sec);
226 buf[1] = bin2bcd(alarm->time.tm_min);
227 buf[2] = bin2bcd(alarm->time.tm_hour);
228 buf[3] = bin2bcd(alarm->time.tm_mday);
229
230 /* clear alarm interrupt enable bit */
231 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
232 if (ret)
233 goto out;
234 control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
235 ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
236 if (ret)
237 goto out;
238
239 /* clear any pending alarm flag */
240 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
241 if (ret)
242 goto out;
243 stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
244 ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
245 if (ret)
246 goto out;
247
248 ret = regmap_bulk_write(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
249 if (ret)
250 goto out;
251
252 if (alarm->enabled) {
253 control |= DS3232_REG_CR_A1IE;
254 ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
255 }
256out:
257 return ret;
258}
259
260static int ds3232_update_alarm(struct device *dev, unsigned int enabled)
261{
262 struct ds3232 *ds3232 = dev_get_drvdata(dev);
263 int control;
264 int ret;
265
266 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
267 if (ret)
268 return ret;
269
270 if (enabled)
271 /* enable alarm1 interrupt */
272 control |= DS3232_REG_CR_A1IE;
273 else
274 /* disable alarm1 interrupt */
275 control &= ~(DS3232_REG_CR_A1IE);
276 ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
277
278 return ret;
279}
280
281/*
282 * Temperature sensor support for ds3232/ds3234 devices.
283 * A user-initiated temperature conversion is not started by this function,
284 * so the temperature is updated once every 64 seconds.
285 */
286static int ds3232_hwmon_read_temp(struct device *dev, long int *mC)
287{
288 struct ds3232 *ds3232 = dev_get_drvdata(dev);
289 u8 temp_buf[2];
290 s16 temp;
291 int ret;
292
293 ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_TEMPERATURE, temp_buf,
294 sizeof(temp_buf));
295 if (ret < 0)
296 return ret;
297
298 /*
299 * Temperature is represented as a 10-bit code with a resolution of
300 * 0.25 degree celsius and encoded in two's complement format.
301 */
302 temp = (temp_buf[0] << 8) | temp_buf[1];
303 temp >>= 6;
304 *mC = temp * 250;
305
306 return 0;
307}
308
309static umode_t ds3232_hwmon_is_visible(const void *data,
310 enum hwmon_sensor_types type,
311 u32 attr, int channel)
312{
313 if (type != hwmon_temp)
314 return 0;
315
316 switch (attr) {
317 case hwmon_temp_input:
318 return 0444;
319 default:
320 return 0;
321 }
322}
323
324static int ds3232_hwmon_read(struct device *dev,
325 enum hwmon_sensor_types type,
326 u32 attr, int channel, long *temp)
327{
328 int err;
329
330 switch (attr) {
331 case hwmon_temp_input:
332 err = ds3232_hwmon_read_temp(dev, temp);
333 break;
334 default:
335 err = -EOPNOTSUPP;
336 break;
337 }
338
339 return err;
340}
341
342static u32 ds3232_hwmon_chip_config[] = {
343 HWMON_C_REGISTER_TZ,
344 0
345};
346
347static const struct hwmon_channel_info ds3232_hwmon_chip = {
348 .type = hwmon_chip,
349 .config = ds3232_hwmon_chip_config,
350};
351
352static u32 ds3232_hwmon_temp_config[] = {
353 HWMON_T_INPUT,
354 0
355};
356
357static const struct hwmon_channel_info ds3232_hwmon_temp = {
358 .type = hwmon_temp,
359 .config = ds3232_hwmon_temp_config,
360};
361
362static const struct hwmon_channel_info *ds3232_hwmon_info[] = {
363 &ds3232_hwmon_chip,
364 &ds3232_hwmon_temp,
365 NULL
366};
367
368static const struct hwmon_ops ds3232_hwmon_hwmon_ops = {
369 .is_visible = ds3232_hwmon_is_visible,
370 .read = ds3232_hwmon_read,
371};
372
373static const struct hwmon_chip_info ds3232_hwmon_chip_info = {
374 .ops = &ds3232_hwmon_hwmon_ops,
375 .info = ds3232_hwmon_info,
376};
377
378static void ds3232_hwmon_register(struct device *dev, const char *name)
379{
380 struct ds3232 *ds3232 = dev_get_drvdata(dev);
381 struct device *hwmon_dev;
382
383 if (!IS_ENABLED(CONFIG_RTC_DRV_DS3232_HWMON))
384 return;
385
386 hwmon_dev = devm_hwmon_device_register_with_info(dev, name, ds3232,
387 &ds3232_hwmon_chip_info,
388 NULL);
389 if (IS_ERR(hwmon_dev)) {
390 dev_err(dev, "unable to register hwmon device %ld\n",
391 PTR_ERR(hwmon_dev));
392 }
393}
394
395static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled)
396{
397 struct ds3232 *ds3232 = dev_get_drvdata(dev);
398
399 if (ds3232->irq <= 0)
400 return -EINVAL;
401
402 return ds3232_update_alarm(dev, enabled);
403}
404
405static irqreturn_t ds3232_irq(int irq, void *dev_id)
406{
407 struct device *dev = dev_id;
408 struct ds3232 *ds3232 = dev_get_drvdata(dev);
409 struct mutex *lock = &ds3232->rtc->ops_lock;
410 int ret;
411 int stat, control;
412
413 mutex_lock(lock);
414
415 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
416 if (ret)
417 goto unlock;
418
419 if (stat & DS3232_REG_SR_A1F) {
420 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
421 if (ret) {
422 dev_warn(ds3232->dev,
423 "Read Control Register error %d\n", ret);
424 } else {
425 /* disable alarm1 interrupt */
426 control &= ~(DS3232_REG_CR_A1IE);
427 ret = regmap_write(ds3232->regmap, DS3232_REG_CR,
428 control);
429 if (ret) {
430 dev_warn(ds3232->dev,
431 "Write Control Register error %d\n",
432 ret);
433 goto unlock;
434 }
435
436 /* clear the alarm pend flag */
437 stat &= ~DS3232_REG_SR_A1F;
438 ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
439 if (ret) {
440 dev_warn(ds3232->dev,
441 "Write Status Register error %d\n",
442 ret);
443 goto unlock;
444 }
445
446 rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
447 }
448 }
449
450unlock:
451 mutex_unlock(lock);
452
453 return IRQ_HANDLED;
454}
455
456static const struct rtc_class_ops ds3232_rtc_ops = {
457 .read_time = ds3232_read_time,
458 .set_time = ds3232_set_time,
459 .read_alarm = ds3232_read_alarm,
460 .set_alarm = ds3232_set_alarm,
461 .alarm_irq_enable = ds3232_alarm_irq_enable,
462};
463
464static int ds3232_nvmem_read(void *priv, unsigned int offset, void *val,
465 size_t bytes)
466{
467 struct regmap *ds3232_regmap = (struct regmap *)priv;
468
469 return regmap_bulk_read(ds3232_regmap, DS3232_REG_SRAM_START + offset,
470 val, bytes);
471}
472
473static int ds3232_nvmem_write(void *priv, unsigned int offset, void *val,
474 size_t bytes)
475{
476 struct regmap *ds3232_regmap = (struct regmap *)priv;
477
478 return regmap_bulk_write(ds3232_regmap, DS3232_REG_SRAM_START + offset,
479 val, bytes);
480}
481
482static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
483 const char *name)
484{
485 struct ds3232 *ds3232;
486 int ret;
487 struct nvmem_config nvmem_cfg = {
488 .name = "ds3232_sram",
489 .stride = 1,
490 .size = DS3232_REG_SRAM_SIZE,
491 .word_size = 1,
492 .reg_read = ds3232_nvmem_read,
493 .reg_write = ds3232_nvmem_write,
494 .priv = regmap,
495 .type = NVMEM_TYPE_BATTERY_BACKED
496 };
497
498 ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL);
499 if (!ds3232)
500 return -ENOMEM;
501
502 ds3232->regmap = regmap;
503 ds3232->irq = irq;
504 ds3232->dev = dev;
505 dev_set_drvdata(dev, ds3232);
506
507 ret = ds3232_check_rtc_status(dev);
508 if (ret)
509 return ret;
510
511 if (ds3232->irq > 0)
512 device_init_wakeup(dev, 1);
513
514 ds3232_hwmon_register(dev, name);
515
516 ds3232->rtc = devm_rtc_device_register(dev, name, &ds3232_rtc_ops,
517 THIS_MODULE);
518 if (IS_ERR(ds3232->rtc))
519 return PTR_ERR(ds3232->rtc);
520
521 ret = rtc_nvmem_register(ds3232->rtc, &nvmem_cfg);
522 if(ret)
523 return ret;
524
525 if (ds3232->irq > 0) {
526 ret = devm_request_threaded_irq(dev, ds3232->irq, NULL,
527 ds3232_irq,
528 IRQF_SHARED | IRQF_ONESHOT,
529 name, dev);
530 if (ret) {
531 device_set_wakeup_capable(dev, 0);
532 ds3232->irq = 0;
533 dev_err(dev, "unable to request IRQ\n");
534 }
535 }
536
537 return 0;
538}
539
540#ifdef CONFIG_PM_SLEEP
541static int ds3232_suspend(struct device *dev)
542{
543 struct ds3232 *ds3232 = dev_get_drvdata(dev);
544
545 if (device_may_wakeup(dev)) {
546 if (enable_irq_wake(ds3232->irq))
547 dev_warn_once(dev, "Cannot set wakeup source\n");
548 }
549
550 return 0;
551}
552
553static int ds3232_resume(struct device *dev)
554{
555 struct ds3232 *ds3232 = dev_get_drvdata(dev);
556
557 if (device_may_wakeup(dev))
558 disable_irq_wake(ds3232->irq);
559
560 return 0;
561}
562#endif
563
564static const struct dev_pm_ops ds3232_pm_ops = {
565 SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
566};
567
568#if IS_ENABLED(CONFIG_I2C)
569
570static int ds3232_i2c_probe(struct i2c_client *client,
571 const struct i2c_device_id *id)
572{
573 struct regmap *regmap;
574 static const struct regmap_config config = {
575 .reg_bits = 8,
576 .val_bits = 8,
577 .max_register = DS3232_REG_SRAM_END,
578 };
579
580 regmap = devm_regmap_init_i2c(client, &config);
581 if (IS_ERR(regmap)) {
582 dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
583 __func__, PTR_ERR(regmap));
584 return PTR_ERR(regmap);
585 }
586
587 return ds3232_probe(&client->dev, regmap, client->irq, client->name);
588}
589
590static const struct i2c_device_id ds3232_id[] = {
591 { "ds3232", 0 },
592 { }
593};
594MODULE_DEVICE_TABLE(i2c, ds3232_id);
595
596static const struct of_device_id ds3232_of_match[] = {
597 { .compatible = "dallas,ds3232" },
598 { }
599};
600MODULE_DEVICE_TABLE(of, ds3232_of_match);
601
602static struct i2c_driver ds3232_driver = {
603 .driver = {
604 .name = "rtc-ds3232",
605 .of_match_table = of_match_ptr(ds3232_of_match),
606 .pm = &ds3232_pm_ops,
607 },
608 .probe = ds3232_i2c_probe,
609 .id_table = ds3232_id,
610};
611
612static int ds3232_register_driver(void)
613{
614 return i2c_add_driver(&ds3232_driver);
615}
616
617static void ds3232_unregister_driver(void)
618{
619 i2c_del_driver(&ds3232_driver);
620}
621
622#else
623
624static int ds3232_register_driver(void)
625{
626 return 0;
627}
628
629static void ds3232_unregister_driver(void)
630{
631}
632
633#endif
634
635#if IS_ENABLED(CONFIG_SPI_MASTER)
636
637static int ds3234_probe(struct spi_device *spi)
638{
639 int res;
640 unsigned int tmp;
641 static const struct regmap_config config = {
642 .reg_bits = 8,
643 .val_bits = 8,
644 .max_register = DS3232_REG_SRAM_END,
645 .write_flag_mask = 0x80,
646 };
647 struct regmap *regmap;
648
649 regmap = devm_regmap_init_spi(spi, &config);
650 if (IS_ERR(regmap)) {
651 dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
652 __func__, PTR_ERR(regmap));
653 return PTR_ERR(regmap);
654 }
655
656 spi->mode = SPI_MODE_3;
657 spi->bits_per_word = 8;
658 spi_setup(spi);
659
660 res = regmap_read(regmap, DS3232_REG_SECONDS, &tmp);
661 if (res)
662 return res;
663
664 /* Control settings
665 *
666 * CONTROL_REG
667 * BIT 7 6 5 4 3 2 1 0
668 * EOSC BBSQW CONV RS2 RS1 INTCN A2IE A1IE
669 *
670 * 0 0 0 1 1 1 0 0
671 *
672 * CONTROL_STAT_REG
673 * BIT 7 6 5 4 3 2 1 0
674 * OSF BB32kHz CRATE1 CRATE0 EN32kHz BSY A2F A1F
675 *
676 * 1 0 0 0 1 0 0 0
677 */
678 res = regmap_read(regmap, DS3232_REG_CR, &tmp);
679 if (res)
680 return res;
681 res = regmap_write(regmap, DS3232_REG_CR, tmp & 0x1c);
682 if (res)
683 return res;
684
685 res = regmap_read(regmap, DS3232_REG_SR, &tmp);
686 if (res)
687 return res;
688 res = regmap_write(regmap, DS3232_REG_SR, tmp & 0x88);
689 if (res)
690 return res;
691
692 /* Print our settings */
693 res = regmap_read(regmap, DS3232_REG_CR, &tmp);
694 if (res)
695 return res;
696 dev_info(&spi->dev, "Control Reg: 0x%02x\n", tmp);
697
698 res = regmap_read(regmap, DS3232_REG_SR, &tmp);
699 if (res)
700 return res;
701 dev_info(&spi->dev, "Ctrl/Stat Reg: 0x%02x\n", tmp);
702
703 return ds3232_probe(&spi->dev, regmap, spi->irq, "ds3234");
704}
705
706static struct spi_driver ds3234_driver = {
707 .driver = {
708 .name = "ds3234",
709 },
710 .probe = ds3234_probe,
711};
712
713static int ds3234_register_driver(void)
714{
715 return spi_register_driver(&ds3234_driver);
716}
717
718static void ds3234_unregister_driver(void)
719{
720 spi_unregister_driver(&ds3234_driver);
721}
722
723#else
724
725static int ds3234_register_driver(void)
726{
727 return 0;
728}
729
730static void ds3234_unregister_driver(void)
731{
732}
733
734#endif
735
736static int __init ds323x_init(void)
737{
738 int ret;
739
740 ret = ds3232_register_driver();
741 if (ret) {
742 pr_err("Failed to register ds3232 driver: %d\n", ret);
743 return ret;
744 }
745
746 ret = ds3234_register_driver();
747 if (ret) {
748 pr_err("Failed to register ds3234 driver: %d\n", ret);
749 ds3232_unregister_driver();
750 }
751
752 return ret;
753}
754module_init(ds323x_init)
755
756static void __exit ds323x_exit(void)
757{
758 ds3234_unregister_driver();
759 ds3232_unregister_driver();
760}
761module_exit(ds323x_exit)
762
763MODULE_AUTHOR("Srikanth Srinivasan <srikanth.srinivasan@freescale.com>");
764MODULE_AUTHOR("Dennis Aberilla <denzzzhome@yahoo.com>");
765MODULE_DESCRIPTION("Maxim/Dallas DS3232/DS3234 RTC Driver");
766MODULE_LICENSE("GPL");
767MODULE_ALIAS("spi:ds3234");