[linux.git] / drivers / rtc / rtc-em3027.c

/*
 * An rtc/i2c driver for the EM Microelectronic EM3027
 * Copyright 2011 CompuLab, Ltd.
 *
 * Author: Mike Rapoport <[email protected]>
 *
 * Based on rtc-ds1672.c by Alessandro Zummo <[email protected]>
 *
 * 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/i2c.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/module.h>
#include <linux/of.h>

/* Registers */
#define EM3027_REG_ON_OFF_CTRL	0x00
#define EM3027_REG_IRQ_CTRL	0x01
#define EM3027_REG_IRQ_FLAGS	0x02
#define EM3027_REG_STATUS	0x03
#define EM3027_REG_RST_CTRL	0x04

#define EM3027_REG_WATCH_SEC	0x08
#define EM3027_REG_WATCH_MIN	0x09
#define EM3027_REG_WATCH_HOUR	0x0a
#define EM3027_REG_WATCH_DATE	0x0b
#define EM3027_REG_WATCH_DAY	0x0c
#define EM3027_REG_WATCH_MON	0x0d
#define EM3027_REG_WATCH_YEAR	0x0e

#define EM3027_REG_ALARM_SEC	0x10
#define EM3027_REG_ALARM_MIN	0x11
#define EM3027_REG_ALARM_HOUR	0x12
#define EM3027_REG_ALARM_DATE	0x13
#define EM3027_REG_ALARM_DAY	0x14
#define EM3027_REG_ALARM_MON	0x15
#define EM3027_REG_ALARM_YEAR	0x16

static struct i2c_driver em3027_driver;

static int em3027_get_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);

	unsigned char addr = EM3027_REG_WATCH_SEC;
	unsigned char buf[7];

	struct i2c_msg msgs[] = {
		{/* setup read addr */
			.addr = client->addr,
			.len = 1,
			.buf = &addr
		},
		{/* read time/date */
			.addr = client->addr,
			.flags = I2C_M_RD,
			.len = 7,
			.buf = buf
		},
	};

	/* read time/date registers */
	if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
		dev_err(&client->dev, "%s: read error\n", __func__);
		return -EIO;
	}

	tm->tm_sec	= bcd2bin(buf[0]);
	tm->tm_min	= bcd2bin(buf[1]);
	tm->tm_hour	= bcd2bin(buf[2]);
	tm->tm_mday	= bcd2bin(buf[3]);
	tm->tm_wday	= bcd2bin(buf[4]);
	tm->tm_mon	= bcd2bin(buf[5]);
	tm->tm_year	= bcd2bin(buf[6]) + 100;

	return 0;
}

static int em3027_set_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned char buf[8];

	struct i2c_msg msg = {
		.addr = client->addr,
		.len = 8,
		.buf = buf,	/* write time/date */
	};

	buf[0] = EM3027_REG_WATCH_SEC;
	buf[1] = bin2bcd(tm->tm_sec);
	buf[2] = bin2bcd(tm->tm_min);
	buf[3] = bin2bcd(tm->tm_hour);
	buf[4] = bin2bcd(tm->tm_mday);
	buf[5] = bin2bcd(tm->tm_wday);
	buf[6] = bin2bcd(tm->tm_mon);
	buf[7] = bin2bcd(tm->tm_year % 100);

	/* write time/date registers */
	if ((i2c_transfer(client->adapter, &msg, 1)) != 1) {
		dev_err(&client->dev, "%s: write error\n", __func__);
		return -EIO;
	}

	return 0;
}

static const struct rtc_class_ops em3027_rtc_ops = {
	.read_time = em3027_get_time,
	.set_time = em3027_set_time,
};

static int em3027_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct rtc_device *rtc;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
		return -ENODEV;

	rtc = devm_rtc_device_register(&client->dev, em3027_driver.driver.name,
				  &em3027_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc))
		return PTR_ERR(rtc);

	i2c_set_clientdata(client, rtc);

	return 0;
}

static const struct i2c_device_id em3027_id[] = {
	{ "em3027", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, em3027_id);

#ifdef CONFIG_OF
static const struct of_device_id em3027_of_match[] = {
	{ .compatible = "emmicro,em3027", },
	{}
};
MODULE_DEVICE_TABLE(of, em3027_of_match);
#endif

static struct i2c_driver em3027_driver = {
	.driver = {
		   .name = "rtc-em3027",
		   .of_match_table = of_match_ptr(em3027_of_match),
	},
	.probe = &em3027_probe,
	.id_table = em3027_id,
};

module_i2c_driver(em3027_driver);

MODULE_AUTHOR("Mike Rapoport <[email protected]>");
MODULE_DESCRIPTION("EM Microelectronic EM3027 RTC driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
ae3551f9 MR	1	/*
	2	* An rtc/i2c driver for the EM Microelectronic EM3027
	3	* Copyright 2011 CompuLab, Ltd.
	4	*
	5	* Author: Mike Rapoport <[email protected]>
	6	*
	7	* Based on rtc-ds1672.c by Alessandro Zummo <[email protected]>
	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/i2c.h>
	15	#include <linux/rtc.h>
	16	#include <linux/bcd.h>
2113852b	17	#include <linux/module.h>
e706974d	18	#include <linux/of.h>
ae3551f9 MR	19
	20	/* Registers */
	21	#define EM3027_REG_ON_OFF_CTRL 0x00
	22	#define EM3027_REG_IRQ_CTRL 0x01
	23	#define EM3027_REG_IRQ_FLAGS 0x02
	24	#define EM3027_REG_STATUS 0x03
	25	#define EM3027_REG_RST_CTRL 0x04
	26
	27	#define EM3027_REG_WATCH_SEC 0x08
	28	#define EM3027_REG_WATCH_MIN 0x09
	29	#define EM3027_REG_WATCH_HOUR 0x0a
	30	#define EM3027_REG_WATCH_DATE 0x0b
	31	#define EM3027_REG_WATCH_DAY 0x0c
	32	#define EM3027_REG_WATCH_MON 0x0d
	33	#define EM3027_REG_WATCH_YEAR 0x0e
	34
	35	#define EM3027_REG_ALARM_SEC 0x10
	36	#define EM3027_REG_ALARM_MIN 0x11
	37	#define EM3027_REG_ALARM_HOUR 0x12
	38	#define EM3027_REG_ALARM_DATE 0x13
	39	#define EM3027_REG_ALARM_DAY 0x14
	40	#define EM3027_REG_ALARM_MON 0x15
	41	#define EM3027_REG_ALARM_YEAR 0x16
	42
	43	static struct i2c_driver em3027_driver;
	44
	45	static int em3027_get_time(struct device dev, struct rtc_time tm)
	46	{
	47	struct i2c_client *client = to_i2c_client(dev);
	48
	49	unsigned char addr = EM3027_REG_WATCH_SEC;
	50	unsigned char buf[7];
	51
	52	struct i2c_msg msgs[] = {
84cab86c S	53	{/* setup read addr */
	54	.addr = client->addr,
	55	.len = 1,
	56	.buf = &addr
	57	},
	58	{/* read time/date */
	59	.addr = client->addr,
	60	.flags = I2C_M_RD,
	61	.len = 7,
	62	.buf = buf
	63	},
ae3551f9 MR	64	};
	65
	66	/* read time/date registers */
	67	if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
	68	dev_err(&client->dev, "%s: read error\n", __func__);
	69	return -EIO;
	70	}
	71
	72	tm->tm_sec = bcd2bin(buf[0]);
	73	tm->tm_min = bcd2bin(buf[1]);
	74	tm->tm_hour = bcd2bin(buf[2]);
	75	tm->tm_mday = bcd2bin(buf[3]);
	76	tm->tm_wday = bcd2bin(buf[4]);
	77	tm->tm_mon = bcd2bin(buf[5]);
	78	tm->tm_year = bcd2bin(buf[6]) + 100;
	79
	80	return 0;
	81	}
	82
	83	static int em3027_set_time(struct device dev, struct rtc_time tm)
	84	{
	85	struct i2c_client *client = to_i2c_client(dev);
	86	unsigned char buf[8];
	87
	88	struct i2c_msg msg = {
84cab86c S	89	.addr = client->addr,
	90	.len = 8,
	91	.buf = buf, /* write time/date */
ae3551f9 MR	92	};
	93
	94	buf[0] = EM3027_REG_WATCH_SEC;
	95	buf[1] = bin2bcd(tm->tm_sec);
	96	buf[2] = bin2bcd(tm->tm_min);
	97	buf[3] = bin2bcd(tm->tm_hour);
	98	buf[4] = bin2bcd(tm->tm_mday);
	99	buf[5] = bin2bcd(tm->tm_wday);
	100	buf[6] = bin2bcd(tm->tm_mon);
	101	buf[7] = bin2bcd(tm->tm_year % 100);
	102
	103	/* write time/date registers */
	104	if ((i2c_transfer(client->adapter, &msg, 1)) != 1) {
	105	dev_err(&client->dev, "%s: write error\n", __func__);
	106	return -EIO;
	107	}
	108
	109	return 0;
	110	}
	111
	112	static const struct rtc_class_ops em3027_rtc_ops = {
	113	.read_time = em3027_get_time,
	114	.set_time = em3027_set_time,
	115	};
	116
	117	static int em3027_probe(struct i2c_client *client,
	118	const struct i2c_device_id *id)
	119	{
	120	struct rtc_device *rtc;
	121
	122	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
	123	return -ENODEV;
	124
019b21d0	125	rtc = devm_rtc_device_register(&client->dev, em3027_driver.driver.name,
ae3551f9 MR	126	&em3027_rtc_ops, THIS_MODULE);
	127	if (IS_ERR(rtc))
	128	return PTR_ERR(rtc);
	129
	130	i2c_set_clientdata(client, rtc);
	131
	132	return 0;
	133	}
	134
45a63518	135	static const struct i2c_device_id em3027_id[] = {
ae3551f9 MR	136	{ "em3027", 0 },
	137	{ }
	138	};
e706974d PR	139	MODULE_DEVICE_TABLE(i2c, em3027_id);
	140
	141	#ifdef CONFIG_OF
	142	static const struct of_device_id em3027_of_match[] = {
	143	{ .compatible = "emmicro,em3027", },
	144	{}
	145	};
	146	MODULE_DEVICE_TABLE(of, em3027_of_match);
	147	#endif
ae3551f9 MR	148
	149	static struct i2c_driver em3027_driver = {
	150	.driver = {
	151	.name = "rtc-em3027",
e706974d	152	.of_match_table = of_match_ptr(em3027_of_match),
ae3551f9 MR	153	},
ae3551f9 MR	154	.probe = &em3027_probe,
ae3551f9 MR	155	.id_table = em3027_id,
	156	};
	157
0abc9201	158	module_i2c_driver(em3027_driver);
ae3551f9 MR	159
	160	MODULE_AUTHOR("Mike Rapoport <[email protected]>");
	161	MODULE_DESCRIPTION("EM Microelectronic EM3027 RTC driver");
	162	MODULE_LICENSE("GPL");