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

// SPDX-License-Identifier: GPL-2.0-only
/*
 * 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.
 */

#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
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
94c01ab6 SW	2	/*
	3	* RTC driver for Maxim MAX8907
	4	*
	5	* Copyright (c) 2011-2012, NVIDIA Corporation.
	6	*
	7	* Based on drivers/rtc/rtc-max8925.c,
	8	* Copyright (C) 2009-2010 Marvell International Ltd.
94c01ab6 SW	9	*/
	10
	11	#include <linux/bcd.h>
	12	#include <linux/i2c.h>
	13	#include <linux/mfd/max8907.h>
	14	#include <linux/module.h>
	15	#include <linux/platform_device.h>
	16	#include <linux/regmap.h>
	17	#include <linux/rtc.h>
	18	#include <linux/slab.h>
	19
	20	enum {
	21	RTC_SEC = 0,
	22	RTC_MIN,
	23	RTC_HOUR,
	24	RTC_WEEKDAY,
	25	RTC_DATE,
	26	RTC_MONTH,
	27	RTC_YEAR1,
	28	RTC_YEAR2,
	29	};
	30
	31	#define TIME_NUM 8
	32	#define ALARM_1SEC (1 << 7)
	33	#define HOUR_12 (1 << 7)
	34	#define HOUR_AM_PM (1 << 5)
	35	#define ALARM0_IRQ (1 << 3)
	36	#define ALARM1_IRQ (1 << 2)
	37	#define ALARM0_STATUS (1 << 2)
	38	#define ALARM1_STATUS (1 << 1)
	39
	40	struct max8907_rtc {
	41	struct max8907 *max8907;
	42	struct regmap *regmap;
	43	struct rtc_device *rtc_dev;
	44	int irq;
	45	};
	46
	47	static irqreturn_t max8907_irq_handler(int irq, void *data)
	48	{
	49	struct max8907_rtc *rtc = data;
	50
75ea799d	51	regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0);
94c01ab6 SW	52
	53	rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF \| RTC_AF);
	54
	55	return IRQ_HANDLED;
	56	}
	57
	58	static void regs_to_tm(u8 regs, struct rtc_time tm)
	59	{
	60	tm->tm_year = bcd2bin(regs[RTC_YEAR2]) * 100 +
	61	bcd2bin(regs[RTC_YEAR1]) - 1900;
	62	tm->tm_mon = bcd2bin(regs[RTC_MONTH] & 0x1f) - 1;
	63	tm->tm_mday = bcd2bin(regs[RTC_DATE] & 0x3f);
75ea799d	64	tm->tm_wday = (regs[RTC_WEEKDAY] & 0x07);
94c01ab6 SW	65	if (regs[RTC_HOUR] & HOUR_12) {
	66	tm->tm_hour = bcd2bin(regs[RTC_HOUR] & 0x01f);
	67	if (tm->tm_hour == 12)
	68	tm->tm_hour = 0;
	69	if (regs[RTC_HOUR] & HOUR_AM_PM)
	70	tm->tm_hour += 12;
	71	} else {
	72	tm->tm_hour = bcd2bin(regs[RTC_HOUR] & 0x03f);
	73	}
	74	tm->tm_min = bcd2bin(regs[RTC_MIN] & 0x7f);
	75	tm->tm_sec = bcd2bin(regs[RTC_SEC] & 0x7f);
	76	}
	77
	78	static void tm_to_regs(struct rtc_time tm, u8 regs)
	79	{
	80	u8 high, low;
	81
	82	high = (tm->tm_year + 1900) / 100;
	83	low = tm->tm_year % 100;
	84	regs[RTC_YEAR2] = bin2bcd(high);
	85	regs[RTC_YEAR1] = bin2bcd(low);
	86	regs[RTC_MONTH] = bin2bcd(tm->tm_mon + 1);
	87	regs[RTC_DATE] = bin2bcd(tm->tm_mday);
75ea799d	88	regs[RTC_WEEKDAY] = tm->tm_wday;
94c01ab6 SW	89	regs[RTC_HOUR] = bin2bcd(tm->tm_hour);
	90	regs[RTC_MIN] = bin2bcd(tm->tm_min);
	91	regs[RTC_SEC] = bin2bcd(tm->tm_sec);
	92	}
	93
	94	static int max8907_rtc_read_time(struct device dev, struct rtc_time tm)
	95	{
	96	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	97	u8 regs[TIME_NUM];
	98	int ret;
	99
	100	ret = regmap_bulk_read(rtc->regmap, MAX8907_REG_RTC_SEC, regs,
	101	TIME_NUM);
	102	if (ret < 0)
	103	return ret;
	104
	105	regs_to_tm(regs, tm);
	106
	107	return 0;
	108	}
	109
	110	static int max8907_rtc_set_time(struct device dev, struct rtc_time tm)
	111	{
	112	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	113	u8 regs[TIME_NUM];
	114
	115	tm_to_regs(tm, regs);
	116
	117	return regmap_bulk_write(rtc->regmap, MAX8907_REG_RTC_SEC, regs,
	118	TIME_NUM);
	119	}
	120
	121	static int max8907_rtc_read_alarm(struct device dev, struct rtc_wkalrm alrm)
	122	{
	123	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	124	u8 regs[TIME_NUM];
	125	unsigned int val;
	126	int ret;
	127
	128	ret = regmap_bulk_read(rtc->regmap, MAX8907_REG_ALARM0_SEC, regs,
	129	TIME_NUM);
	130	if (ret < 0)
	131	return ret;
	132
	133	regs_to_tm(regs, &alrm->time);
	134
	135	ret = regmap_read(rtc->regmap, MAX8907_REG_ALARM0_CNTL, &val);
	136	if (ret < 0)
	137	return ret;
	138
	139	alrm->enabled = !!(val & 0x7f);
	140
	141	return 0;
	142	}
	143
	144	static int max8907_rtc_set_alarm(struct device dev, struct rtc_wkalrm alrm)
	145	{
	146	struct max8907_rtc *rtc = dev_get_drvdata(dev);
	147	u8 regs[TIME_NUM];
	148	int ret;
	149
	150	tm_to_regs(&alrm->time, regs);
	151
	152	/* Disable alarm while we update the target time */
75ea799d	153	ret = regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0);
94c01ab6 SW	154	if (ret < 0)
	155	return ret;
	156
	157	ret = regmap_bulk_write(rtc->regmap, MAX8907_REG_ALARM0_SEC, regs,
	158	TIME_NUM);
	159	if (ret < 0)
	160	return ret;
	161
	162	if (alrm->enabled)
75ea799d	163	ret = regmap_write(rtc->regmap, MAX8907_REG_ALARM0_CNTL, 0x77);
94c01ab6 SW	164
	165	return ret;
	166	}
	167
	168	static const struct rtc_class_ops max8907_rtc_ops = {
	169	.read_time = max8907_rtc_read_time,
	170	.set_time = max8907_rtc_set_time,
	171	.read_alarm = max8907_rtc_read_alarm,
	172	.set_alarm = max8907_rtc_set_alarm,
	173	};
	174
5a167f45	175	static int max8907_rtc_probe(struct platform_device *pdev)
94c01ab6 SW	176	{
	177	struct max8907 *max8907 = dev_get_drvdata(pdev->dev.parent);
	178	struct max8907_rtc *rtc;
	179	int ret;
	180
	181	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
	182	if (!rtc)
	183	return -ENOMEM;
	184	platform_set_drvdata(pdev, rtc);
	185
	186	rtc->max8907 = max8907;
	187	rtc->regmap = max8907->regmap_rtc;
	188
ac4e7d49	189	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8907-rtc",
94c01ab6 SW	190	&max8907_rtc_ops, THIS_MODULE);
	191	if (IS_ERR(rtc->rtc_dev)) {
	192	ret = PTR_ERR(rtc->rtc_dev);
	193	dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
	194	return ret;
	195	}
	196
	197	rtc->irq = regmap_irq_get_virq(max8907->irqc_rtc,
	198	MAX8907_IRQ_RTC_ALARM0);
2fa76062 SK	199	if (rtc->irq < 0)
2fa76062 SK	200	return rtc->irq;
94c01ab6	201
83a72c87 JH	202	ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
	203	max8907_irq_handler,
	204	IRQF_ONESHOT, "max8907-alarm0", rtc);
2fa76062	205	if (ret < 0)
94c01ab6 SW	206	dev_err(&pdev->dev, "Failed to request IRQ%d: %d\n",
94c01ab6 SW	207	rtc->irq, ret);
94c01ab6	208
94c01ab6 SW	209	return ret;
	210	}
	211
94c01ab6 SW	212	static struct platform_driver max8907_rtc_driver = {
	213	.driver = {
	214	.name = "max8907-rtc",
94c01ab6 SW	215	},
94c01ab6 SW	216	.probe = max8907_rtc_probe,
94c01ab6 SW	217	};
	218	module_platform_driver(max8907_rtc_driver);
	219
	220	MODULE_DESCRIPTION("Maxim MAX8907 RTC driver");
	221	MODULE_LICENSE("GPL v2");