2 * RTC driver for Maxim MAX77686
4 * Copyright (C) 2012 Samsung Electronics Co.Ltd
6 * based on rtc-max8997.c
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.
15 #include <linux/slab.h>
16 #include <linux/rtc.h>
17 #include <linux/delay.h>
18 #include <linux/mutex.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/mfd/max77686-private.h>
22 #include <linux/irqdomain.h>
23 #include <linux/regmap.h>
25 /* RTC Control Register */
26 #define BCD_EN_SHIFT 0
27 #define BCD_EN_MASK (1 << BCD_EN_SHIFT)
28 #define MODEL24_SHIFT 1
29 #define MODEL24_MASK (1 << MODEL24_SHIFT)
30 /* RTC Update Register1 */
31 #define RTC_UDR_SHIFT 0
32 #define RTC_UDR_MASK (1 << RTC_UDR_SHIFT)
33 #define RTC_RBUDR_SHIFT 4
34 #define RTC_RBUDR_MASK (1 << RTC_RBUDR_SHIFT)
35 /* WTSR and SMPL Register */
38 #define WTSR_EN_SHIFT 6
39 #define SMPL_EN_SHIFT 7
40 #define WTSRT_MASK (3 << WTSRT_SHIFT)
41 #define SMPLT_MASK (3 << SMPLT_SHIFT)
42 #define WTSR_EN_MASK (1 << WTSR_EN_SHIFT)
43 #define SMPL_EN_MASK (1 << SMPL_EN_SHIFT)
44 /* RTC Hour register */
45 #define HOUR_PM_SHIFT 6
46 #define HOUR_PM_MASK (1 << HOUR_PM_SHIFT)
47 /* RTC Alarm Enable */
48 #define ALARM_ENABLE_SHIFT 7
49 #define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT)
51 #define MAX77686_RTC_UPDATE_DELAY 16
52 #undef MAX77686_RTC_WTSR_SMPL
65 struct max77686_rtc_info
{
67 struct max77686_dev
*max77686
;
68 struct i2c_client
*rtc
;
69 struct rtc_device
*rtc_dev
;
72 struct regmap
*regmap
;
78 enum MAX77686_RTC_OP
{
83 static inline int max77686_rtc_calculate_wday(u8 shifted
)
93 static void max77686_rtc_data_to_tm(u8
*data
, struct rtc_time
*tm
,
96 tm
->tm_sec
= data
[RTC_SEC
] & 0x7f;
97 tm
->tm_min
= data
[RTC_MIN
] & 0x7f;
99 tm
->tm_hour
= data
[RTC_HOUR
] & 0x1f;
101 tm
->tm_hour
= data
[RTC_HOUR
] & 0x0f;
102 if (data
[RTC_HOUR
] & HOUR_PM_MASK
)
106 tm
->tm_wday
= max77686_rtc_calculate_wday(data
[RTC_WEEKDAY
] & 0x7f);
107 tm
->tm_mday
= data
[RTC_DATE
] & 0x1f;
108 tm
->tm_mon
= (data
[RTC_MONTH
] & 0x0f) - 1;
109 tm
->tm_year
= (data
[RTC_YEAR
] & 0x7f) + 100;
114 static int max77686_rtc_tm_to_data(struct rtc_time
*tm
, u8
*data
)
116 data
[RTC_SEC
] = tm
->tm_sec
;
117 data
[RTC_MIN
] = tm
->tm_min
;
118 data
[RTC_HOUR
] = tm
->tm_hour
;
119 data
[RTC_WEEKDAY
] = 1 << tm
->tm_wday
;
120 data
[RTC_DATE
] = tm
->tm_mday
;
121 data
[RTC_MONTH
] = tm
->tm_mon
+ 1;
122 data
[RTC_YEAR
] = tm
->tm_year
> 100 ? (tm
->tm_year
- 100) : 0;
124 if (tm
->tm_year
< 100) {
125 pr_warn("%s: MAX77686 RTC cannot handle the year %d."
126 "Assume it's 2000.\n", __func__
, 1900 + tm
->tm_year
);
132 static int max77686_rtc_update(struct max77686_rtc_info
*info
,
133 enum MAX77686_RTC_OP op
)
138 if (op
== MAX77686_RTC_WRITE
)
139 data
= 1 << RTC_UDR_SHIFT
;
141 data
= 1 << RTC_RBUDR_SHIFT
;
143 ret
= regmap_update_bits(info
->max77686
->rtc_regmap
,
144 MAX77686_RTC_UPDATE0
, data
, data
);
146 dev_err(info
->dev
, "%s: fail to write update reg(ret=%d, data=0x%x)\n",
147 __func__
, ret
, data
);
149 /* Minimum 16ms delay required before RTC update. */
150 msleep(MAX77686_RTC_UPDATE_DELAY
);
156 static int max77686_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
158 struct max77686_rtc_info
*info
= dev_get_drvdata(dev
);
159 u8 data
[RTC_NR_TIME
];
162 mutex_lock(&info
->lock
);
164 ret
= max77686_rtc_update(info
, MAX77686_RTC_READ
);
168 ret
= regmap_bulk_read(info
->max77686
->rtc_regmap
,
169 MAX77686_RTC_SEC
, data
, RTC_NR_TIME
);
171 dev_err(info
->dev
, "%s: fail to read time reg(%d)\n", __func__
, ret
);
175 max77686_rtc_data_to_tm(data
, tm
, info
->rtc_24hr_mode
);
177 ret
= rtc_valid_tm(tm
);
180 mutex_unlock(&info
->lock
);
184 static int max77686_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
186 struct max77686_rtc_info
*info
= dev_get_drvdata(dev
);
187 u8 data
[RTC_NR_TIME
];
190 ret
= max77686_rtc_tm_to_data(tm
, data
);
194 mutex_lock(&info
->lock
);
196 ret
= regmap_bulk_write(info
->max77686
->rtc_regmap
,
197 MAX77686_RTC_SEC
, data
, RTC_NR_TIME
);
199 dev_err(info
->dev
, "%s: fail to write time reg(%d)\n", __func__
,
204 ret
= max77686_rtc_update(info
, MAX77686_RTC_WRITE
);
207 mutex_unlock(&info
->lock
);
211 static int max77686_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
213 struct max77686_rtc_info
*info
= dev_get_drvdata(dev
);
214 u8 data
[RTC_NR_TIME
];
218 mutex_lock(&info
->lock
);
220 ret
= max77686_rtc_update(info
, MAX77686_RTC_READ
);
224 ret
= regmap_bulk_read(info
->max77686
->rtc_regmap
,
225 MAX77686_ALARM1_SEC
, data
, RTC_NR_TIME
);
227 dev_err(info
->dev
, "%s:%d fail to read alarm reg(%d)\n",
228 __func__
, __LINE__
, ret
);
232 max77686_rtc_data_to_tm(data
, &alrm
->time
, info
->rtc_24hr_mode
);
235 for (i
= 0; i
< RTC_NR_TIME
; i
++) {
236 if (data
[i
] & ALARM_ENABLE_MASK
) {
243 ret
= regmap_read(info
->max77686
->regmap
, MAX77686_REG_STATUS2
, &val
);
245 dev_err(info
->dev
, "%s:%d fail to read status2 reg(%d)\n",
246 __func__
, __LINE__
, ret
);
250 if (val
& (1 << 4)) /* RTCA1 */
254 mutex_unlock(&info
->lock
);
258 static int max77686_rtc_stop_alarm(struct max77686_rtc_info
*info
)
260 u8 data
[RTC_NR_TIME
];
264 if (!mutex_is_locked(&info
->lock
))
265 dev_warn(info
->dev
, "%s: should have mutex locked\n", __func__
);
267 ret
= max77686_rtc_update(info
, MAX77686_RTC_READ
);
271 ret
= regmap_bulk_read(info
->max77686
->rtc_regmap
,
272 MAX77686_ALARM1_SEC
, data
, RTC_NR_TIME
);
274 dev_err(info
->dev
, "%s: fail to read alarm reg(%d)\n",
279 max77686_rtc_data_to_tm(data
, &tm
, info
->rtc_24hr_mode
);
281 for (i
= 0; i
< RTC_NR_TIME
; i
++)
282 data
[i
] &= ~ALARM_ENABLE_MASK
;
284 ret
= regmap_bulk_write(info
->max77686
->rtc_regmap
,
285 MAX77686_ALARM1_SEC
, data
, RTC_NR_TIME
);
287 dev_err(info
->dev
, "%s: fail to write alarm reg(%d)\n",
292 ret
= max77686_rtc_update(info
, MAX77686_RTC_WRITE
);
297 static int max77686_rtc_start_alarm(struct max77686_rtc_info
*info
)
299 u8 data
[RTC_NR_TIME
];
303 if (!mutex_is_locked(&info
->lock
))
304 dev_warn(info
->dev
, "%s: should have mutex locked\n", __func__
);
306 ret
= max77686_rtc_update(info
, MAX77686_RTC_READ
);
310 ret
= regmap_bulk_read(info
->max77686
->rtc_regmap
,
311 MAX77686_ALARM1_SEC
, data
, RTC_NR_TIME
);
313 dev_err(info
->dev
, "%s: fail to read alarm reg(%d)\n",
318 max77686_rtc_data_to_tm(data
, &tm
, info
->rtc_24hr_mode
);
320 data
[RTC_SEC
] |= (1 << ALARM_ENABLE_SHIFT
);
321 data
[RTC_MIN
] |= (1 << ALARM_ENABLE_SHIFT
);
322 data
[RTC_HOUR
] |= (1 << ALARM_ENABLE_SHIFT
);
323 data
[RTC_WEEKDAY
] &= ~ALARM_ENABLE_MASK
;
324 if (data
[RTC_MONTH
] & 0xf)
325 data
[RTC_MONTH
] |= (1 << ALARM_ENABLE_SHIFT
);
326 if (data
[RTC_YEAR
] & 0x7f)
327 data
[RTC_YEAR
] |= (1 << ALARM_ENABLE_SHIFT
);
328 if (data
[RTC_DATE
] & 0x1f)
329 data
[RTC_DATE
] |= (1 << ALARM_ENABLE_SHIFT
);
331 ret
= regmap_bulk_write(info
->max77686
->rtc_regmap
,
332 MAX77686_ALARM1_SEC
, data
, RTC_NR_TIME
);
334 dev_err(info
->dev
, "%s: fail to write alarm reg(%d)\n",
339 ret
= max77686_rtc_update(info
, MAX77686_RTC_WRITE
);
344 static int max77686_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
346 struct max77686_rtc_info
*info
= dev_get_drvdata(dev
);
347 u8 data
[RTC_NR_TIME
];
350 ret
= max77686_rtc_tm_to_data(&alrm
->time
, data
);
354 mutex_lock(&info
->lock
);
356 ret
= max77686_rtc_stop_alarm(info
);
360 ret
= regmap_bulk_write(info
->max77686
->rtc_regmap
,
361 MAX77686_ALARM1_SEC
, data
, RTC_NR_TIME
);
364 dev_err(info
->dev
, "%s: fail to write alarm reg(%d)\n",
369 ret
= max77686_rtc_update(info
, MAX77686_RTC_WRITE
);
374 ret
= max77686_rtc_start_alarm(info
);
376 mutex_unlock(&info
->lock
);
380 static int max77686_rtc_alarm_irq_enable(struct device
*dev
,
381 unsigned int enabled
)
383 struct max77686_rtc_info
*info
= dev_get_drvdata(dev
);
386 mutex_lock(&info
->lock
);
388 ret
= max77686_rtc_start_alarm(info
);
390 ret
= max77686_rtc_stop_alarm(info
);
391 mutex_unlock(&info
->lock
);
396 static irqreturn_t
max77686_rtc_alarm_irq(int irq
, void *data
)
398 struct max77686_rtc_info
*info
= data
;
400 dev_info(info
->dev
, "%s:irq(%d)\n", __func__
, irq
);
402 rtc_update_irq(info
->rtc_dev
, 1, RTC_IRQF
| RTC_AF
);
407 static const struct rtc_class_ops max77686_rtc_ops
= {
408 .read_time
= max77686_rtc_read_time
,
409 .set_time
= max77686_rtc_set_time
,
410 .read_alarm
= max77686_rtc_read_alarm
,
411 .set_alarm
= max77686_rtc_set_alarm
,
412 .alarm_irq_enable
= max77686_rtc_alarm_irq_enable
,
415 #ifdef MAX77686_RTC_WTSR_SMPL
416 static void max77686_rtc_enable_wtsr(struct max77686_rtc_info
*info
, bool enable
)
419 unsigned int val
, mask
;
422 val
= (1 << WTSR_EN_SHIFT
) | (3 << WTSRT_SHIFT
);
426 mask
= WTSR_EN_MASK
| WTSRT_MASK
;
428 dev_info(info
->dev
, "%s: %s WTSR\n", __func__
,
429 enable
? "enable" : "disable");
431 ret
= regmap_update_bits(info
->max77686
->rtc_regmap
,
432 MAX77686_WTSR_SMPL_CNTL
, mask
, val
);
434 dev_err(info
->dev
, "%s: fail to update WTSR reg(%d)\n",
439 max77686_rtc_update(info
, MAX77686_RTC_WRITE
);
442 static void max77686_rtc_enable_smpl(struct max77686_rtc_info
*info
, bool enable
)
445 unsigned int val
, mask
;
448 val
= (1 << SMPL_EN_SHIFT
) | (0 << SMPLT_SHIFT
);
452 mask
= SMPL_EN_MASK
| SMPLT_MASK
;
454 dev_info(info
->dev
, "%s: %s SMPL\n", __func__
,
455 enable
? "enable" : "disable");
457 ret
= regmap_update_bits(info
->max77686
->rtc_regmap
,
458 MAX77686_WTSR_SMPL_CNTL
, mask
, val
);
460 dev_err(info
->dev
, "%s: fail to update SMPL reg(%d)\n",
465 max77686_rtc_update(info
, MAX77686_RTC_WRITE
);
468 regmap_read(info
->max77686
->rtc_regmap
, MAX77686_WTSR_SMPL_CNTL
, &val
);
469 dev_info(info
->dev
, "%s: WTSR_SMPL(0x%02x)\n", __func__
, val
);
471 #endif /* MAX77686_RTC_WTSR_SMPL */
473 static int max77686_rtc_init_reg(struct max77686_rtc_info
*info
)
478 /* Set RTC control register : Binary mode, 24hour mdoe */
479 data
[0] = (1 << BCD_EN_SHIFT
) | (1 << MODEL24_SHIFT
);
480 data
[1] = (0 << BCD_EN_SHIFT
) | (1 << MODEL24_SHIFT
);
482 info
->rtc_24hr_mode
= 1;
484 ret
= regmap_bulk_write(info
->max77686
->rtc_regmap
, MAX77686_RTC_CONTROLM
, data
, 2);
486 dev_err(info
->dev
, "%s: fail to write controlm reg(%d)\n",
491 ret
= max77686_rtc_update(info
, MAX77686_RTC_WRITE
);
495 static struct regmap_config max77686_rtc_regmap_config
= {
500 static int max77686_rtc_probe(struct platform_device
*pdev
)
502 struct max77686_dev
*max77686
= dev_get_drvdata(pdev
->dev
.parent
);
503 struct max77686_rtc_info
*info
;
506 dev_info(&pdev
->dev
, "%s\n", __func__
);
508 info
= devm_kzalloc(&pdev
->dev
, sizeof(struct max77686_rtc_info
),
513 mutex_init(&info
->lock
);
514 info
->dev
= &pdev
->dev
;
515 info
->max77686
= max77686
;
516 info
->rtc
= max77686
->rtc
;
517 info
->max77686
->rtc_regmap
= devm_regmap_init_i2c(info
->max77686
->rtc
,
518 &max77686_rtc_regmap_config
);
519 if (IS_ERR(info
->max77686
->rtc_regmap
)) {
520 ret
= PTR_ERR(info
->max77686
->rtc_regmap
);
521 dev_err(info
->max77686
->dev
, "Failed to allocate register map: %d\n",
525 platform_set_drvdata(pdev
, info
);
527 ret
= max77686_rtc_init_reg(info
);
530 dev_err(&pdev
->dev
, "Failed to initialize RTC reg:%d\n", ret
);
534 #ifdef MAX77686_RTC_WTSR_SMPL
535 max77686_rtc_enable_wtsr(info
, true);
536 max77686_rtc_enable_smpl(info
, true);
539 device_init_wakeup(&pdev
->dev
, 1);
541 info
->rtc_dev
= devm_rtc_device_register(&pdev
->dev
, "max77686-rtc",
542 &max77686_rtc_ops
, THIS_MODULE
);
544 if (IS_ERR(info
->rtc_dev
)) {
545 dev_info(&pdev
->dev
, "%s: fail\n", __func__
);
547 ret
= PTR_ERR(info
->rtc_dev
);
548 dev_err(&pdev
->dev
, "Failed to register RTC device: %d\n", ret
);
553 virq
= irq_create_mapping(max77686
->irq_domain
, MAX77686_RTCIRQ_RTCA1
);
560 ret
= devm_request_threaded_irq(&pdev
->dev
, virq
, NULL
,
561 max77686_rtc_alarm_irq
, 0, "rtc-alarm0", info
);
563 dev_err(&pdev
->dev
, "Failed to request alarm IRQ: %d: %d\n",
570 static void max77686_rtc_shutdown(struct platform_device
*pdev
)
572 #ifdef MAX77686_RTC_WTSR_SMPL
573 struct max77686_rtc_info
*info
= platform_get_drvdata(pdev
);
577 for (i
= 0; i
< 3; i
++) {
578 max77686_rtc_enable_wtsr(info
, false);
579 regmap_read(info
->max77686
->rtc_regmap
, MAX77686_WTSR_SMPL_CNTL
, &val
);
580 dev_info(info
->dev
, "%s: WTSR_SMPL reg(0x%02x)\n", __func__
,
582 if (val
& WTSR_EN_MASK
) {
583 dev_emerg(info
->dev
, "%s: fail to disable WTSR\n",
586 dev_info(info
->dev
, "%s: success to disable WTSR\n",
592 /* Disable SMPL when power off */
593 max77686_rtc_enable_smpl(info
, false);
594 #endif /* MAX77686_RTC_WTSR_SMPL */
597 static const struct platform_device_id rtc_id
[] = {
598 { "max77686-rtc", 0 },
602 static struct platform_driver max77686_rtc_driver
= {
604 .name
= "max77686-rtc",
605 .owner
= THIS_MODULE
,
607 .probe
= max77686_rtc_probe
,
608 .shutdown
= max77686_rtc_shutdown
,
612 module_platform_driver(max77686_rtc_driver
);
614 MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
615 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
616 MODULE_LICENSE("GPL");