[linux.git] / drivers / rtc / rtc-max8907.c

/*
 * RTC driver for Maxim MAX8907
 *
 * Copyright (c) 2011-2012, NVIDIA Corporation.
 *
 * Based on drivers/rtc/rtc-max8925.c,
 * Copyright (C) 2009-2010 Marvell International Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/bcd.h>
#include <linux/i2c.h>
#include <linux/mfd/max8907.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/rtc.h>
#include <linux/slab.h>

enum {
	RTC_SEC = 0,
	RTC_MIN,
	RTC_HOUR,
	RTC_WEEKDAY,
	RTC_DATE,
	RTC_MONTH,
	RTC_YEAR1,
	RTC_YEAR2,
};

#define TIME_NUM			8
#define ALARM_1SEC			(1 << 7)
#define HOUR_12				(1 << 7)
#define HOUR_AM_PM			(1 << 5)
#define ALARM0_IRQ			(1 << 3)
#define ALARM1_IRQ			(1 << 2)
#define ALARM0_STATUS			(1 << 2)
#define ALARM1_STATUS			(1 << 1)

struct max8907_rtc {
	struct max8907		*max8907;
	struct regmap		*regmap;
	struct rtc_device	*rtc_dev;
	int			irq;
};

static irqreturn_t max8907_irq_handler(int irq, void *data)
{
	struct max8907_rtc *rtc = data;

	regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0);

	rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);

	return IRQ_HANDLED;
}

static void regs_to_tm(u8 *regs, struct rtc_time *tm)
{
	tm->tm_year = bcd2bin(regs[RTC_YEAR2]) * 100 +
		bcd2bin(regs[RTC_YEAR1]) - 1900;
	tm->tm_mon = bcd2bin(regs[RTC_MONTH] & 0x1f) - 1;
	tm->tm_mday = bcd2bin(regs[RTC_DATE] & 0x3f);
	tm->tm_wday = (regs[RTC_WEEKDAY] & 0x07);
	if (regs[RTC_HOUR] & HOUR_12) {
		tm->tm_hour = bcd2bin(regs[RTC_HOUR] & 0x01f);
		if (tm->tm_hour == 12)
			tm->tm_hour = 0;
		if (regs[RTC_HOUR] & HOUR_AM_PM)
			tm->tm_hour += 12;
	} else {
		tm->tm_hour = bcd2bin(regs[RTC_HOUR] & 0x03f);
	}
	tm->tm_min = bcd2bin(regs[RTC_MIN] & 0x7f);
	tm->tm_sec = bcd2bin(regs[RTC_SEC] & 0x7f);
}

static void tm_to_regs(struct rtc_time *tm, u8 *regs)
{
	u8 high, low;

	high = (tm->tm_year + 1900) / 100;
	low = tm->tm_year % 100;
	regs[RTC_YEAR2] = bin2bcd(high);
	regs[RTC_YEAR1] = bin2bcd(low);
	regs[RTC_MONTH] = bin2bcd(tm->tm_mon + 1);
	regs[RTC_DATE] = bin2bcd(tm->tm_mday);
	regs[RTC_WEEKDAY] = tm->tm_wday;
	regs[RTC_HOUR] = bin2bcd(tm->tm_hour);
	regs[RTC_MIN] = bin2bcd(tm->tm_min);
	regs[RTC_SEC] = bin2bcd(tm->tm_sec);
}

static int max8907_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	u8 regs[TIME_NUM];
	int ret;

	ret = regmap_bulk_read(rtc->regmap, MAX8907_REG_RTC_SEC, regs,
			       TIME_NUM);
	if (ret < 0)
		return ret;

	regs_to_tm(regs, tm);

	return 0;
}

static int max8907_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	u8 regs[TIME_NUM];

	tm_to_regs(tm, regs);

	return regmap_bulk_write(rtc->regmap, MAX8907_REG_RTC_SEC, regs,
				 TIME_NUM);
}

static int max8907_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	u8 regs[TIME_NUM];
	unsigned int val;
	int ret;

	ret = regmap_bulk_read(rtc->regmap, MAX8907_REG_ALARM0_SEC, regs,
			       TIME_NUM);
	if (ret < 0)
		return ret;

	regs_to_tm(regs, &alrm->time);

	ret = regmap_read(rtc->regmap, MAX8907_REG_ALARM0_CNTL, &val);
	if (ret < 0)
		return ret;

	alrm->enabled = !!(val & 0x7f);

	return 0;
}

static int max8907_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	u8 regs[TIME_NUM];
	int ret;

	tm_to_regs(&alrm->time, regs);

	/* Disable alarm while we update the target time */
	ret = regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0);
	if (ret < 0)
		return ret;

	ret = regmap_bulk_write(rtc->regmap, MAX8907_REG_ALARM0_SEC, regs,
				TIME_NUM);
	if (ret < 0)
		return ret;

	if (alrm->enabled)
		ret = regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0x77);

	return ret;
}

static const struct rtc_class_ops max8907_rtc_ops = {
	.read_time	= max8907_rtc_read_time,
	.set_time	= max8907_rtc_set_time,
	.read_alarm	= max8907_rtc_read_alarm,
	.set_alarm	= max8907_rtc_set_alarm,
};

static int max8907_rtc_probe(struct platform_device *pdev)
{
	struct max8907 *max8907 = dev_get_drvdata(pdev->dev.parent);
	struct max8907_rtc *rtc;
	int ret;

	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
	if (!rtc)
		return -ENOMEM;
	platform_set_drvdata(pdev, rtc);

	rtc->max8907 = max8907;
	rtc->regmap = max8907->regmap_rtc;

	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8907-rtc",
					&max8907_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc->rtc_dev)) {
		ret = PTR_ERR(rtc->rtc_dev);
		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
		return ret;
	}

	rtc->irq = regmap_irq_get_virq(max8907->irqc_rtc,
				       MAX8907_IRQ_RTC_ALARM0);
	if (rtc->irq < 0)
		return rtc->irq;

	ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
				max8907_irq_handler,
				IRQF_ONESHOT, "max8907-alarm0", rtc);
	if (ret < 0)
		dev_err(&pdev->dev, "Failed to request IRQ%d: %d\n",
			rtc->irq, ret);

	return ret;
}

static struct platform_driver max8907_rtc_driver = {
	.driver = {
		.name = "max8907-rtc",
	},
	.probe = max8907_rtc_probe,
};
module_platform_driver(max8907_rtc_driver);

MODULE_DESCRIPTION("Maxim MAX8907 RTC driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
94c01ab6 SW	1	/*
	2	* RTC driver for Maxim MAX8907
	3	*
	4	* Copyright (c) 2011-2012, NVIDIA Corporation.
	5	*
	6	* Based on drivers/rtc/rtc-max8925.c,
	7	* Copyright (C) 2009-2010 Marvell International Ltd.
	8	*
	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.
	12	*/
	13
	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>
	22
	23	enum {
	24	RTC_SEC = 0,
	25	RTC_MIN,
	26	RTC_HOUR,
	27	RTC_WEEKDAY,
	28	RTC_DATE,
	29	RTC_MONTH,
	30	RTC_YEAR1,
	31	RTC_YEAR2,
	32	};
	33
	34	#define TIME_NUM 8
	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)
	42
	43	struct max8907_rtc {
	44	struct max8907 *max8907;
	45	struct regmap *regmap;
	46	struct rtc_device *rtc_dev;
	47	int irq;
	48	};
	49
	50	static irqreturn_t max8907_irq_handler(int irq, void *data)
	51	{
	52	struct max8907_rtc *rtc = data;
	53
75ea799d	54	regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0);
94c01ab6 SW	55
	56	rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF \| RTC_AF);
	57
	58	return IRQ_HANDLED;
	59	}
	60
	61	static void regs_to_tm(u8 regs, struct rtc_time tm)
	62	{
	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);
75ea799d	67	tm->tm_wday = (regs[RTC_WEEKDAY] & 0x07);
94c01ab6 SW	68	if (regs[RTC_HOUR] & HOUR_12) {
	69	tm->tm_hour = bcd2bin(regs[RTC_HOUR] & 0x01f);
	70	if (tm->tm_hour == 12)
	71	tm->tm_hour = 0;
	72	if (regs[RTC_HOUR] & HOUR_AM_PM)
	73	tm->tm_hour += 12;
	74	} else {
	75	tm->tm_hour = bcd2bin(regs[RTC_HOUR] & 0x03f);
	76	}
	77	tm->tm_min = bcd2bin(regs[RTC_MIN] & 0x7f);
	78	tm->tm_sec = bcd2bin(regs[RTC_SEC] & 0x7f);
	79	}
	80
	81	static void tm_to_regs(struct rtc_time tm, u8 regs)
	82	{
	83	u8 high, low;
	84
	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);
75ea799d	91	regs[RTC_WEEKDAY] = tm->tm_wday;
94c01ab6 SW	92	regs[RTC_HOUR] = bin2bcd(tm->tm_hour);
	93	regs[RTC_MIN] = bin2bcd(tm->tm_min);
	94	regs[RTC_SEC] = bin2bcd(tm->tm_sec);
	95	}
	96
	97	static int max8907_rtc_read_time(struct device dev, struct rtc_time tm)
	98	{
	99	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	100	u8 regs[TIME_NUM];
	101	int ret;
	102
	103	ret = regmap_bulk_read(rtc->regmap, MAX8907_REG_RTC_SEC, regs,
	104	TIME_NUM);
	105	if (ret < 0)
	106	return ret;
	107
	108	regs_to_tm(regs, tm);
	109
	110	return 0;
	111	}
	112
	113	static int max8907_rtc_set_time(struct device dev, struct rtc_time tm)
	114	{
	115	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	116	u8 regs[TIME_NUM];
	117
	118	tm_to_regs(tm, regs);
	119
	120	return regmap_bulk_write(rtc->regmap, MAX8907_REG_RTC_SEC, regs,
	121	TIME_NUM);
	122	}
	123
	124	static int max8907_rtc_read_alarm(struct device dev, struct rtc_wkalrm alrm)
	125	{
	126	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	127	u8 regs[TIME_NUM];
	128	unsigned int val;
	129	int ret;
	130
	131	ret = regmap_bulk_read(rtc->regmap, MAX8907_REG_ALARM0_SEC, regs,
	132	TIME_NUM);
	133	if (ret < 0)
	134	return ret;
	135
	136	regs_to_tm(regs, &alrm->time);
	137
	138	ret = regmap_read(rtc->regmap, MAX8907_REG_ALARM0_CNTL, &val);
	139	if (ret < 0)
	140	return ret;
	141
	142	alrm->enabled = !!(val & 0x7f);
	143
	144	return 0;
	145	}
	146
	147	static int max8907_rtc_set_alarm(struct device dev, struct rtc_wkalrm alrm)
	148	{
	149	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	150	u8 regs[TIME_NUM];
	151	int ret;
	152
	153	tm_to_regs(&alrm->time, regs);
	154
	155	/* Disable alarm while we update the target time */
75ea799d	156	ret = regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0);
94c01ab6 SW	157	if (ret < 0)
	158	return ret;
	159
	160	ret = regmap_bulk_write(rtc->regmap, MAX8907_REG_ALARM0_SEC, regs,
	161	TIME_NUM);
	162	if (ret < 0)
	163	return ret;
	164
	165	if (alrm->enabled)
75ea799d	166	ret = regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0x77);
94c01ab6 SW	167
	168	return ret;
	169	}
	170
	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,
	176	};
	177
5a167f45	178	static int max8907_rtc_probe(struct platform_device *pdev)
94c01ab6 SW	179	{
	180	struct max8907 *max8907 = dev_get_drvdata(pdev->dev.parent);
	181	struct max8907_rtc *rtc;
	182	int ret;
	183
	184	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
	185	if (!rtc)
	186	return -ENOMEM;
	187	platform_set_drvdata(pdev, rtc);
	188
	189	rtc->max8907 = max8907;
	190	rtc->regmap = max8907->regmap_rtc;
	191
ac4e7d49	192	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8907-rtc",
94c01ab6 SW	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);
	197	return ret;
	198	}
	199
	200	rtc->irq = regmap_irq_get_virq(max8907->irqc_rtc,
	201	MAX8907_IRQ_RTC_ALARM0);
2fa76062 SK	202	if (rtc->irq < 0)
2fa76062 SK	203	return rtc->irq;
94c01ab6	204
83a72c87 JH	205	ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
	206	max8907_irq_handler,
	207	IRQF_ONESHOT, "max8907-alarm0", rtc);
2fa76062	208	if (ret < 0)
94c01ab6 SW	209	dev_err(&pdev->dev, "Failed to request IRQ%d: %d\n",
94c01ab6 SW	210	rtc->irq, ret);
94c01ab6	211
94c01ab6 SW	212	return ret;
	213	}
	214
94c01ab6 SW	215	static struct platform_driver max8907_rtc_driver = {
	216	.driver = {
	217	.name = "max8907-rtc",
94c01ab6 SW	218	},
94c01ab6 SW	219	.probe = max8907_rtc_probe,
94c01ab6 SW	220	};
	221	module_platform_driver(max8907_rtc_driver);
	222
	223	MODULE_DESCRIPTION("Maxim MAX8907 RTC driver");
	224	MODULE_LICENSE("GPL v2");