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1/*
2 * RTC client/driver for the Maxim/Dallas DS3232 Real-Time Clock over I2C
3 *
4 * Copyright (C) 2009-2011 Freescale Semiconductor.
5 * Author: Jack Lan <jack.lan@freescale.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
11 */
12/*
13 * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
14 * recommened in .../Documentation/i2c/writing-clients section
15 * "Sending and receiving", using SMBus level communication is preferred.
16 */
17
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/interrupt.h>
21#include <linux/i2c.h>
22#include <linux/rtc.h>
23#include <linux/bcd.h>
24#include <linux/workqueue.h>
25#include <linux/slab.h>
26
27#define DS3232_REG_SECONDS 0x00
28#define DS3232_REG_MINUTES 0x01
29#define DS3232_REG_HOURS 0x02
30#define DS3232_REG_AMPM 0x02
31#define DS3232_REG_DAY 0x03
32#define DS3232_REG_DATE 0x04
33#define DS3232_REG_MONTH 0x05
34#define DS3232_REG_CENTURY 0x05
35#define DS3232_REG_YEAR 0x06
36#define DS3232_REG_ALARM1 0x07 /* Alarm 1 BASE */
37#define DS3232_REG_ALARM2 0x0B /* Alarm 2 BASE */
38#define DS3232_REG_CR 0x0E /* Control register */
39# define DS3232_REG_CR_nEOSC 0x80
40# define DS3232_REG_CR_INTCN 0x04
41# define DS3232_REG_CR_A2IE 0x02
42# define DS3232_REG_CR_A1IE 0x01
43
44#define DS3232_REG_SR 0x0F /* control/status register */
45# define DS3232_REG_SR_OSF 0x80
46# define DS3232_REG_SR_BSY 0x04
47# define DS3232_REG_SR_A2F 0x02
48# define DS3232_REG_SR_A1F 0x01
49
50struct ds3232 {
51 struct i2c_client *client;
52 struct rtc_device *rtc;
53 struct work_struct work;
54
55 /* The mutex protects alarm operations, and prevents a race
56 * between the enable_irq() in the workqueue and the free_irq()
57 * in the remove function.
58 */
59 struct mutex mutex;
60 int exiting;
61};
62
63static struct i2c_driver ds3232_driver;
64
65static int ds3232_check_rtc_status(struct i2c_client *client)
66{
67 int ret = 0;
68 int control, stat;
69
70 stat = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
71 if (stat < 0)
72 return stat;
73
74 if (stat & DS3232_REG_SR_OSF)
75 dev_warn(&client->dev,
76 "oscillator discontinuity flagged, "
77 "time unreliable\n");
78
79 stat &= ~(DS3232_REG_SR_OSF | DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
80
81 ret = i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
82 if (ret < 0)
83 return ret;
84
85 /* If the alarm is pending, clear it before requesting
86 * the interrupt, so an interrupt event isn't reported
87 * before everything is initialized.
88 */
89
90 control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
91 if (control < 0)
92 return control;
93
94 control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
95 control |= DS3232_REG_CR_INTCN;
96
97 return i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
98}
99
100static int ds3232_read_time(struct device *dev, struct rtc_time *time)
101{
102 struct i2c_client *client = to_i2c_client(dev);
103 int ret;
104 u8 buf[7];
105 unsigned int year, month, day, hour, minute, second;
106 unsigned int week, twelve_hr, am_pm;
107 unsigned int century, add_century = 0;
108
109 ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_SECONDS, 7, buf);
110
111 if (ret < 0)
112 return ret;
113 if (ret < 7)
114 return -EIO;
115
116 second = buf[0];
117 minute = buf[1];
118 hour = buf[2];
119 week = buf[3];
120 day = buf[4];
121 month = buf[5];
122 year = buf[6];
123
124 /* Extract additional information for AM/PM and century */
125
126 twelve_hr = hour & 0x40;
127 am_pm = hour & 0x20;
128 century = month & 0x80;
129
130 /* Write to rtc_time structure */
131
132 time->tm_sec = bcd2bin(second);
133 time->tm_min = bcd2bin(minute);
134 if (twelve_hr) {
135 /* Convert to 24 hr */
136 if (am_pm)
137 time->tm_hour = bcd2bin(hour & 0x1F) + 12;
138 else
139 time->tm_hour = bcd2bin(hour & 0x1F);
140 } else {
141 time->tm_hour = bcd2bin(hour);
142 }
143
144 /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
145 time->tm_wday = bcd2bin(week) - 1;
146 time->tm_mday = bcd2bin(day);
147 /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
148 time->tm_mon = bcd2bin(month & 0x7F) - 1;
149 if (century)
150 add_century = 100;
151
152 time->tm_year = bcd2bin(year) + add_century;
153
154 return rtc_valid_tm(time);
155}
156
157static int ds3232_set_time(struct device *dev, struct rtc_time *time)
158{
159 struct i2c_client *client = to_i2c_client(dev);
160 u8 buf[7];
161
162 /* Extract time from rtc_time and load into ds3232*/
163
164 buf[0] = bin2bcd(time->tm_sec);
165 buf[1] = bin2bcd(time->tm_min);
166 buf[2] = bin2bcd(time->tm_hour);
167 /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
168 buf[3] = bin2bcd(time->tm_wday + 1);
169 buf[4] = bin2bcd(time->tm_mday); /* Date */
170 /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
171 buf[5] = bin2bcd(time->tm_mon + 1);
172 if (time->tm_year >= 100) {
173 buf[5] |= 0x80;
174 buf[6] = bin2bcd(time->tm_year - 100);
175 } else {
176 buf[6] = bin2bcd(time->tm_year);
177 }
178
179 return i2c_smbus_write_i2c_block_data(client,
180 DS3232_REG_SECONDS, 7, buf);
181}
182
183/*
184 * DS3232 has two alarm, we only use alarm1
185 * According to linux specification, only support one-shot alarm
186 * no periodic alarm mode
187 */
188static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
189{
190 struct i2c_client *client = to_i2c_client(dev);
191 struct ds3232 *ds3232 = i2c_get_clientdata(client);
192 int control, stat;
193 int ret;
194 u8 buf[4];
195
196 mutex_lock(&ds3232->mutex);
197
198 ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
199 if (ret < 0)
200 goto out;
201 stat = ret;
202 ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
203 if (ret < 0)
204 goto out;
205 control = ret;
206 ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
207 if (ret < 0)
208 goto out;
209
210 alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
211 alarm->time.tm_min = bcd2bin(buf[1] & 0x7F);
212 alarm->time.tm_hour = bcd2bin(buf[2] & 0x7F);
213 alarm->time.tm_mday = bcd2bin(buf[3] & 0x7F);
214
215 alarm->time.tm_mon = -1;
216 alarm->time.tm_year = -1;
217 alarm->time.tm_wday = -1;
218 alarm->time.tm_yday = -1;
219 alarm->time.tm_isdst = -1;
220
221 alarm->enabled = !!(control & DS3232_REG_CR_A1IE);
222 alarm->pending = !!(stat & DS3232_REG_SR_A1F);
223
224 ret = 0;
225out:
226 mutex_unlock(&ds3232->mutex);
227 return ret;
228}
229
230/*
231 * linux rtc-module does not support wday alarm
232 * and only 24h time mode supported indeed
233 */
234static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
235{
236 struct i2c_client *client = to_i2c_client(dev);
237 struct ds3232 *ds3232 = i2c_get_clientdata(client);
238 int control, stat;
239 int ret;
240 u8 buf[4];
241
242 if (client->irq <= 0)
243 return -EINVAL;
244
245 mutex_lock(&ds3232->mutex);
246
247 buf[0] = bin2bcd(alarm->time.tm_sec);
248 buf[1] = bin2bcd(alarm->time.tm_min);
249 buf[2] = bin2bcd(alarm->time.tm_hour);
250 buf[3] = bin2bcd(alarm->time.tm_mday);
251
252 /* clear alarm interrupt enable bit */
253 ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
254 if (ret < 0)
255 goto out;
256 control = ret;
257 control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
258 ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
259 if (ret < 0)
260 goto out;
261
262 /* clear any pending alarm flag */
263 ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
264 if (ret < 0)
265 goto out;
266 stat = ret;
267 stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
268 ret = i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
269 if (ret < 0)
270 goto out;
271
272 ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
273
274 if (alarm->enabled) {
275 control |= DS3232_REG_CR_A1IE;
276 ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
277 }
278out:
279 mutex_unlock(&ds3232->mutex);
280 return ret;
281}
282
283static void ds3232_update_alarm(struct i2c_client *client)
284{
285 struct ds3232 *ds3232 = i2c_get_clientdata(client);
286 int control;
287 int ret;
288 u8 buf[4];
289
290 mutex_lock(&ds3232->mutex);
291
292 ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
293 if (ret < 0)
294 goto unlock;
295
296 buf[0] = bcd2bin(buf[0]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
297 0x80 : buf[0];
298 buf[1] = bcd2bin(buf[1]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
299 0x80 : buf[1];
300 buf[2] = bcd2bin(buf[2]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
301 0x80 : buf[2];
302 buf[3] = bcd2bin(buf[3]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
303 0x80 : buf[3];
304
305 ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
306 if (ret < 0)
307 goto unlock;
308
309 control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
310 if (control < 0)
311 goto unlock;
312
313 if (ds3232->rtc->irq_data & (RTC_AF | RTC_UF))
314 /* enable alarm1 interrupt */
315 control |= DS3232_REG_CR_A1IE;
316 else
317 /* disable alarm1 interrupt */
318 control &= ~(DS3232_REG_CR_A1IE);
319 i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
320
321unlock:
322 mutex_unlock(&ds3232->mutex);
323}
324
325static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled)
326{
327 struct i2c_client *client = to_i2c_client(dev);
328 struct ds3232 *ds3232 = i2c_get_clientdata(client);
329
330 if (client->irq <= 0)
331 return -EINVAL;
332
333 if (enabled)
334 ds3232->rtc->irq_data |= RTC_AF;
335 else
336 ds3232->rtc->irq_data &= ~RTC_AF;
337
338 ds3232_update_alarm(client);
339 return 0;
340}
341
342static irqreturn_t ds3232_irq(int irq, void *dev_id)
343{
344 struct i2c_client *client = dev_id;
345 struct ds3232 *ds3232 = i2c_get_clientdata(client);
346
347 disable_irq_nosync(irq);
348 schedule_work(&ds3232->work);
349 return IRQ_HANDLED;
350}
351
352static void ds3232_work(struct work_struct *work)
353{
354 struct ds3232 *ds3232 = container_of(work, struct ds3232, work);
355 struct i2c_client *client = ds3232->client;
356 int stat, control;
357
358 mutex_lock(&ds3232->mutex);
359
360 stat = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
361 if (stat < 0)
362 goto unlock;
363
364 if (stat & DS3232_REG_SR_A1F) {
365 control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
366 if (control < 0)
367 goto out;
368 /* disable alarm1 interrupt */
369 control &= ~(DS3232_REG_CR_A1IE);
370 i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
371
372 /* clear the alarm pend flag */
373 stat &= ~DS3232_REG_SR_A1F;
374 i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
375
376 rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
377 }
378
379out:
380 if (!ds3232->exiting)
381 enable_irq(client->irq);
382unlock:
383 mutex_unlock(&ds3232->mutex);
384}
385
386static const struct rtc_class_ops ds3232_rtc_ops = {
387 .read_time = ds3232_read_time,
388 .set_time = ds3232_set_time,
389 .read_alarm = ds3232_read_alarm,
390 .set_alarm = ds3232_set_alarm,
391 .alarm_irq_enable = ds3232_alarm_irq_enable,
392};
393
394static int __devinit ds3232_probe(struct i2c_client *client,
395 const struct i2c_device_id *id)
396{
397 struct ds3232 *ds3232;
398 int ret;
399
400 ds3232 = kzalloc(sizeof(struct ds3232), GFP_KERNEL);
401 if (!ds3232)
402 return -ENOMEM;
403
404 ds3232->client = client;
405 i2c_set_clientdata(client, ds3232);
406
407 INIT_WORK(&ds3232->work, ds3232_work);
408 mutex_init(&ds3232->mutex);
409
410 ret = ds3232_check_rtc_status(client);
411 if (ret)
412 goto out_free;
413
414 ds3232->rtc = rtc_device_register(client->name, &client->dev,
415 &ds3232_rtc_ops, THIS_MODULE);
416 if (IS_ERR(ds3232->rtc)) {
417 ret = PTR_ERR(ds3232->rtc);
418 dev_err(&client->dev, "unable to register the class device\n");
419 goto out_irq;
420 }
421
422 if (client->irq >= 0) {
423 ret = request_irq(client->irq, ds3232_irq, 0,
424 "ds3232", client);
425 if (ret) {
426 dev_err(&client->dev, "unable to request IRQ\n");
427 goto out_free;
428 }
429 }
430
431 return 0;
432
433out_irq:
434 if (client->irq >= 0)
435 free_irq(client->irq, client);
436
437out_free:
438 kfree(ds3232);
439 return ret;
440}
441
442static int __devexit ds3232_remove(struct i2c_client *client)
443{
444 struct ds3232 *ds3232 = i2c_get_clientdata(client);
445
446 if (client->irq >= 0) {
447 mutex_lock(&ds3232->mutex);
448 ds3232->exiting = 1;
449 mutex_unlock(&ds3232->mutex);
450
451 free_irq(client->irq, client);
452 cancel_work_sync(&ds3232->work);
453 }
454
455 rtc_device_unregister(ds3232->rtc);
456 kfree(ds3232);
457 return 0;
458}
459
460static const struct i2c_device_id ds3232_id[] = {
461 { "ds3232", 0 },
462 { }
463};
464MODULE_DEVICE_TABLE(i2c, ds3232_id);
465
466static struct i2c_driver ds3232_driver = {
467 .driver = {
468 .name = "rtc-ds3232",
469 .owner = THIS_MODULE,
470 },
471 .probe = ds3232_probe,
472 .remove = __devexit_p(ds3232_remove),
473 .id_table = ds3232_id,
474};
475
476static int __init ds3232_init(void)
477{
478 return i2c_add_driver(&ds3232_driver);
479}
480
481static void __exit ds3232_exit(void)
482{
483 i2c_del_driver(&ds3232_driver);
484}
485
486module_init(ds3232_init);
487module_exit(ds3232_exit);
488
489MODULE_AUTHOR("Srikanth Srinivasan <srikanth.srinivasan@freescale.com>");
490MODULE_DESCRIPTION("Maxim/Dallas DS3232 RTC Driver");
491MODULE_LICENSE("GPL");
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 int ret;
410 int stat, control;
411
412 rtc_lock(ds3232->rtc);
413
414 ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
415 if (ret)
416 goto unlock;
417
418 if (stat & DS3232_REG_SR_A1F) {
419 ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
420 if (ret) {
421 dev_warn(ds3232->dev,
422 "Read Control Register error %d\n", ret);
423 } else {
424 /* disable alarm1 interrupt */
425 control &= ~(DS3232_REG_CR_A1IE);
426 ret = regmap_write(ds3232->regmap, DS3232_REG_CR,
427 control);
428 if (ret) {
429 dev_warn(ds3232->dev,
430 "Write Control Register error %d\n",
431 ret);
432 goto unlock;
433 }
434
435 /* clear the alarm pend flag */
436 stat &= ~DS3232_REG_SR_A1F;
437 ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
438 if (ret) {
439 dev_warn(ds3232->dev,
440 "Write Status Register error %d\n",
441 ret);
442 goto unlock;
443 }
444
445 rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
446 }
447 }
448
449unlock:
450 rtc_unlock(ds3232->rtc);
451
452 return IRQ_HANDLED;
453}
454
455static const struct rtc_class_ops ds3232_rtc_ops = {
456 .read_time = ds3232_read_time,
457 .set_time = ds3232_set_time,
458 .read_alarm = ds3232_read_alarm,
459 .set_alarm = ds3232_set_alarm,
460 .alarm_irq_enable = ds3232_alarm_irq_enable,
461};
462
463static int ds3232_nvmem_read(void *priv, unsigned int offset, void *val,
464 size_t bytes)
465{
466 struct regmap *ds3232_regmap = (struct regmap *)priv;
467
468 return regmap_bulk_read(ds3232_regmap, DS3232_REG_SRAM_START + offset,
469 val, bytes);
470}
471
472static int ds3232_nvmem_write(void *priv, unsigned int offset, void *val,
473 size_t bytes)
474{
475 struct regmap *ds3232_regmap = (struct regmap *)priv;
476
477 return regmap_bulk_write(ds3232_regmap, DS3232_REG_SRAM_START + offset,
478 val, bytes);
479}
480
481static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
482 const char *name)
483{
484 struct ds3232 *ds3232;
485 int ret;
486 struct nvmem_config nvmem_cfg = {
487 .name = "ds3232_sram",
488 .stride = 1,
489 .size = DS3232_REG_SRAM_SIZE,
490 .word_size = 1,
491 .reg_read = ds3232_nvmem_read,
492 .reg_write = ds3232_nvmem_write,
493 .priv = regmap,
494 .type = NVMEM_TYPE_BATTERY_BACKED
495 };
496
497 ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL);
498 if (!ds3232)
499 return -ENOMEM;
500
501 ds3232->regmap = regmap;
502 ds3232->irq = irq;
503 ds3232->dev = dev;
504 dev_set_drvdata(dev, ds3232);
505
506 ret = ds3232_check_rtc_status(dev);
507 if (ret)
508 return ret;
509
510 if (ds3232->irq > 0)
511 device_init_wakeup(dev, 1);
512
513 ds3232_hwmon_register(dev, name);
514
515 ds3232->rtc = devm_rtc_device_register(dev, name, &ds3232_rtc_ops,
516 THIS_MODULE);
517 if (IS_ERR(ds3232->rtc))
518 return PTR_ERR(ds3232->rtc);
519
520 ret = devm_rtc_nvmem_register(ds3232->rtc, &nvmem_cfg);
521 if(ret)
522 return ret;
523
524 if (ds3232->irq > 0) {
525 ret = devm_request_threaded_irq(dev, ds3232->irq, NULL,
526 ds3232_irq,
527 IRQF_SHARED | IRQF_ONESHOT,
528 name, dev);
529 if (ret) {
530 device_set_wakeup_capable(dev, 0);
531 ds3232->irq = 0;
532 dev_err(dev, "unable to request IRQ\n");
533 }
534 }
535
536 return 0;
537}
538
539#ifdef CONFIG_PM_SLEEP
540static int ds3232_suspend(struct device *dev)
541{
542 struct ds3232 *ds3232 = dev_get_drvdata(dev);
543
544 if (device_may_wakeup(dev)) {
545 if (enable_irq_wake(ds3232->irq))
546 dev_warn_once(dev, "Cannot set wakeup source\n");
547 }
548
549 return 0;
550}
551
552static int ds3232_resume(struct device *dev)
553{
554 struct ds3232 *ds3232 = dev_get_drvdata(dev);
555
556 if (device_may_wakeup(dev))
557 disable_irq_wake(ds3232->irq);
558
559 return 0;
560}
561#endif
562
563static const struct dev_pm_ops ds3232_pm_ops = {
564 SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
565};
566
567#if IS_ENABLED(CONFIG_I2C)
568
569static int ds3232_i2c_probe(struct i2c_client *client)
570{
571 struct regmap *regmap;
572 static const struct regmap_config config = {
573 .reg_bits = 8,
574 .val_bits = 8,
575 .max_register = DS3232_REG_SRAM_END,
576 };
577
578 regmap = devm_regmap_init_i2c(client, &config);
579 if (IS_ERR(regmap)) {
580 dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
581 __func__, PTR_ERR(regmap));
582 return PTR_ERR(regmap);
583 }
584
585 return ds3232_probe(&client->dev, regmap, client->irq, client->name);
586}
587
588static const struct i2c_device_id ds3232_id[] = {
589 { "ds3232", 0 },
590 { }
591};
592MODULE_DEVICE_TABLE(i2c, ds3232_id);
593
594static const __maybe_unused struct of_device_id ds3232_of_match[] = {
595 { .compatible = "dallas,ds3232" },
596 { }
597};
598MODULE_DEVICE_TABLE(of, ds3232_of_match);
599
600static struct i2c_driver ds3232_driver = {
601 .driver = {
602 .name = "rtc-ds3232",
603 .of_match_table = of_match_ptr(ds3232_of_match),
604 .pm = &ds3232_pm_ops,
605 },
606 .probe_new = ds3232_i2c_probe,
607 .id_table = ds3232_id,
608};
609
610static int ds3232_register_driver(void)
611{
612 return i2c_add_driver(&ds3232_driver);
613}
614
615static void ds3232_unregister_driver(void)
616{
617 i2c_del_driver(&ds3232_driver);
618}
619
620#else
621
622static int ds3232_register_driver(void)
623{
624 return 0;
625}
626
627static void ds3232_unregister_driver(void)
628{
629}
630
631#endif
632
633#if IS_ENABLED(CONFIG_SPI_MASTER)
634
635static int ds3234_probe(struct spi_device *spi)
636{
637 int res;
638 unsigned int tmp;
639 static const struct regmap_config config = {
640 .reg_bits = 8,
641 .val_bits = 8,
642 .max_register = DS3232_REG_SRAM_END,
643 .write_flag_mask = 0x80,
644 };
645 struct regmap *regmap;
646
647 regmap = devm_regmap_init_spi(spi, &config);
648 if (IS_ERR(regmap)) {
649 dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
650 __func__, PTR_ERR(regmap));
651 return PTR_ERR(regmap);
652 }
653
654 spi->mode = SPI_MODE_3;
655 spi->bits_per_word = 8;
656 spi_setup(spi);
657
658 res = regmap_read(regmap, DS3232_REG_SECONDS, &tmp);
659 if (res)
660 return res;
661
662 /* Control settings
663 *
664 * CONTROL_REG
665 * BIT 7 6 5 4 3 2 1 0
666 * EOSC BBSQW CONV RS2 RS1 INTCN A2IE A1IE
667 *
668 * 0 0 0 1 1 1 0 0
669 *
670 * CONTROL_STAT_REG
671 * BIT 7 6 5 4 3 2 1 0
672 * OSF BB32kHz CRATE1 CRATE0 EN32kHz BSY A2F A1F
673 *
674 * 1 0 0 0 1 0 0 0
675 */
676 res = regmap_read(regmap, DS3232_REG_CR, &tmp);
677 if (res)
678 return res;
679 res = regmap_write(regmap, DS3232_REG_CR, tmp & 0x1c);
680 if (res)
681 return res;
682
683 res = regmap_read(regmap, DS3232_REG_SR, &tmp);
684 if (res)
685 return res;
686 res = regmap_write(regmap, DS3232_REG_SR, tmp & 0x88);
687 if (res)
688 return res;
689
690 /* Print our settings */
691 res = regmap_read(regmap, DS3232_REG_CR, &tmp);
692 if (res)
693 return res;
694 dev_info(&spi->dev, "Control Reg: 0x%02x\n", tmp);
695
696 res = regmap_read(regmap, DS3232_REG_SR, &tmp);
697 if (res)
698 return res;
699 dev_info(&spi->dev, "Ctrl/Stat Reg: 0x%02x\n", tmp);
700
701 return ds3232_probe(&spi->dev, regmap, spi->irq, "ds3234");
702}
703
704static struct spi_driver ds3234_driver = {
705 .driver = {
706 .name = "ds3234",
707 },
708 .probe = ds3234_probe,
709};
710
711static int ds3234_register_driver(void)
712{
713 return spi_register_driver(&ds3234_driver);
714}
715
716static void ds3234_unregister_driver(void)
717{
718 spi_unregister_driver(&ds3234_driver);
719}
720
721#else
722
723static int ds3234_register_driver(void)
724{
725 return 0;
726}
727
728static void ds3234_unregister_driver(void)
729{
730}
731
732#endif
733
734static int __init ds323x_init(void)
735{
736 int ret;
737
738 ret = ds3232_register_driver();
739 if (ret) {
740 pr_err("Failed to register ds3232 driver: %d\n", ret);
741 return ret;
742 }
743
744 ret = ds3234_register_driver();
745 if (ret) {
746 pr_err("Failed to register ds3234 driver: %d\n", ret);
747 ds3232_unregister_driver();
748 }
749
750 return ret;
751}
752module_init(ds323x_init)
753
754static void __exit ds323x_exit(void)
755{
756 ds3234_unregister_driver();
757 ds3232_unregister_driver();
758}
759module_exit(ds323x_exit)
760
761MODULE_AUTHOR("Srikanth Srinivasan <srikanth.srinivasan@freescale.com>");
762MODULE_AUTHOR("Dennis Aberilla <denzzzhome@yahoo.com>");
763MODULE_DESCRIPTION("Maxim/Dallas DS3232/DS3234 RTC Driver");
764MODULE_LICENSE("GPL");
765MODULE_ALIAS("spi:ds3234");