2 * RTC driver for Maxim MAX8907
4 * Copyright (c) 2011-2012, NVIDIA Corporation.
6 * Based on drivers/rtc/rtc-max8925.c,
7 * Copyright (C) 2009-2010 Marvell International Ltd.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #include <linux/bcd.h>
15 #include <linux/i2c.h>
16 #include <linux/mfd/max8907.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/regmap.h>
20 #include <linux/rtc.h>
21 #include <linux/slab.h>
35 #define ALARM_1SEC (1 << 7)
36 #define HOUR_12 (1 << 7)
37 #define HOUR_AM_PM (1 << 5)
38 #define ALARM0_IRQ (1 << 3)
39 #define ALARM1_IRQ (1 << 2)
40 #define ALARM0_STATUS (1 << 2)
41 #define ALARM1_STATUS (1 << 1)
44 struct max8907
*max8907
;
45 struct regmap
*regmap
;
46 struct rtc_device
*rtc_dev
;
50 static irqreturn_t
max8907_irq_handler(int irq
, void *data
)
52 struct max8907_rtc
*rtc
= data
;
54 regmap_write(rtc
->regmap
, MAX8907_REG_ALARM0_CNTL
, 0);
56 rtc_update_irq(rtc
->rtc_dev
, 1, RTC_IRQF
| RTC_AF
);
61 static void regs_to_tm(u8
*regs
, struct rtc_time
*tm
)
63 tm
->tm_year
= bcd2bin(regs
[RTC_YEAR2
]) * 100 +
64 bcd2bin(regs
[RTC_YEAR1
]) - 1900;
65 tm
->tm_mon
= bcd2bin(regs
[RTC_MONTH
] & 0x1f) - 1;
66 tm
->tm_mday
= bcd2bin(regs
[RTC_DATE
] & 0x3f);
67 tm
->tm_wday
= (regs
[RTC_WEEKDAY
] & 0x07);
68 if (regs
[RTC_HOUR
] & HOUR_12
) {
69 tm
->tm_hour
= bcd2bin(regs
[RTC_HOUR
] & 0x01f);
70 if (tm
->tm_hour
== 12)
72 if (regs
[RTC_HOUR
] & HOUR_AM_PM
)
75 tm
->tm_hour
= bcd2bin(regs
[RTC_HOUR
] & 0x03f);
77 tm
->tm_min
= bcd2bin(regs
[RTC_MIN
] & 0x7f);
78 tm
->tm_sec
= bcd2bin(regs
[RTC_SEC
] & 0x7f);
81 static void tm_to_regs(struct rtc_time
*tm
, u8
*regs
)
85 high
= (tm
->tm_year
+ 1900) / 100;
86 low
= tm
->tm_year
% 100;
87 regs
[RTC_YEAR2
] = bin2bcd(high
);
88 regs
[RTC_YEAR1
] = bin2bcd(low
);
89 regs
[RTC_MONTH
] = bin2bcd(tm
->tm_mon
+ 1);
90 regs
[RTC_DATE
] = bin2bcd(tm
->tm_mday
);
91 regs
[RTC_WEEKDAY
] = tm
->tm_wday
;
92 regs
[RTC_HOUR
] = bin2bcd(tm
->tm_hour
);
93 regs
[RTC_MIN
] = bin2bcd(tm
->tm_min
);
94 regs
[RTC_SEC
] = bin2bcd(tm
->tm_sec
);
97 static int max8907_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
99 struct max8907_rtc
*rtc
= dev_get_drvdata(dev
);
103 ret
= regmap_bulk_read(rtc
->regmap
, MAX8907_REG_RTC_SEC
, regs
,
108 regs_to_tm(regs
, tm
);
113 static int max8907_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
115 struct max8907_rtc
*rtc
= dev_get_drvdata(dev
);
118 tm_to_regs(tm
, regs
);
120 return regmap_bulk_write(rtc
->regmap
, MAX8907_REG_RTC_SEC
, regs
,
124 static int max8907_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
126 struct max8907_rtc
*rtc
= dev_get_drvdata(dev
);
131 ret
= regmap_bulk_read(rtc
->regmap
, MAX8907_REG_ALARM0_SEC
, regs
,
136 regs_to_tm(regs
, &alrm
->time
);
138 ret
= regmap_read(rtc
->regmap
, MAX8907_REG_ALARM0_CNTL
, &val
);
142 alrm
->enabled
= !!(val
& 0x7f);
147 static int max8907_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
149 struct max8907_rtc
*rtc
= dev_get_drvdata(dev
);
153 tm_to_regs(&alrm
->time
, regs
);
155 /* Disable alarm while we update the target time */
156 ret
= regmap_write(rtc
->regmap
, MAX8907_REG_ALARM0_CNTL
, 0);
160 ret
= regmap_bulk_write(rtc
->regmap
, MAX8907_REG_ALARM0_SEC
, regs
,
166 ret
= regmap_write(rtc
->regmap
, MAX8907_REG_ALARM0_CNTL
, 0x77);
171 static const struct rtc_class_ops max8907_rtc_ops
= {
172 .read_time
= max8907_rtc_read_time
,
173 .set_time
= max8907_rtc_set_time
,
174 .read_alarm
= max8907_rtc_read_alarm
,
175 .set_alarm
= max8907_rtc_set_alarm
,
178 static int max8907_rtc_probe(struct platform_device
*pdev
)
180 struct max8907
*max8907
= dev_get_drvdata(pdev
->dev
.parent
);
181 struct max8907_rtc
*rtc
;
184 rtc
= devm_kzalloc(&pdev
->dev
, sizeof(*rtc
), GFP_KERNEL
);
187 platform_set_drvdata(pdev
, rtc
);
189 rtc
->max8907
= max8907
;
190 rtc
->regmap
= max8907
->regmap_rtc
;
192 rtc
->rtc_dev
= devm_rtc_device_register(&pdev
->dev
, "max8907-rtc",
193 &max8907_rtc_ops
, THIS_MODULE
);
194 if (IS_ERR(rtc
->rtc_dev
)) {
195 ret
= PTR_ERR(rtc
->rtc_dev
);
196 dev_err(&pdev
->dev
, "Failed to register RTC device: %d\n", ret
);
200 rtc
->irq
= regmap_irq_get_virq(max8907
->irqc_rtc
,
201 MAX8907_IRQ_RTC_ALARM0
);
205 ret
= devm_request_threaded_irq(&pdev
->dev
, rtc
->irq
, NULL
,
207 IRQF_ONESHOT
, "max8907-alarm0", rtc
);
209 dev_err(&pdev
->dev
, "Failed to request IRQ%d: %d\n",
215 static struct platform_driver max8907_rtc_driver
= {
217 .name
= "max8907-rtc",
218 .owner
= THIS_MODULE
,
220 .probe
= max8907_rtc_probe
,
222 module_platform_driver(max8907_rtc_driver
);
224 MODULE_DESCRIPTION("Maxim MAX8907 RTC driver");
225 MODULE_LICENSE("GPL v2");