[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>

/* 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[] = {
		{client->addr, 0, 1, &addr},		/* setup read addr */
		{client->addr, I2C_M_RD, 7, buf},	/* read time/date */
	};

	/* 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 = {
		client->addr, 0, 8, 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 = rtc_device_register(em3027_driver.driver.name, &client->dev,
				  &em3027_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc))
		return PTR_ERR(rtc);

	i2c_set_clientdata(client, rtc);

	return 0;
}

static int em3027_remove(struct i2c_client *client)
{
	struct rtc_device *rtc = i2c_get_clientdata(client);

	if (rtc)
		rtc_device_unregister(rtc);

	return 0;
}

static struct i2c_device_id em3027_id[] = {
	{ "em3027", 0 },
	{ }
};

static struct i2c_driver em3027_driver = {
	.driver = {
		   .name = "rtc-em3027",
	},
	.probe = &em3027_probe,
	.remove = &em3027_remove,
	.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>
ae3551f9 MR	18
	19	/* Registers */
	20	#define EM3027_REG_ON_OFF_CTRL 0x00
	21	#define EM3027_REG_IRQ_CTRL 0x01
	22	#define EM3027_REG_IRQ_FLAGS 0x02
	23	#define EM3027_REG_STATUS 0x03
	24	#define EM3027_REG_RST_CTRL 0x04
	25
	26	#define EM3027_REG_WATCH_SEC 0x08
	27	#define EM3027_REG_WATCH_MIN 0x09
	28	#define EM3027_REG_WATCH_HOUR 0x0a
	29	#define EM3027_REG_WATCH_DATE 0x0b
	30	#define EM3027_REG_WATCH_DAY 0x0c
	31	#define EM3027_REG_WATCH_MON 0x0d
	32	#define EM3027_REG_WATCH_YEAR 0x0e
	33
	34	#define EM3027_REG_ALARM_SEC 0x10
	35	#define EM3027_REG_ALARM_MIN 0x11
	36	#define EM3027_REG_ALARM_HOUR 0x12
	37	#define EM3027_REG_ALARM_DATE 0x13
	38	#define EM3027_REG_ALARM_DAY 0x14
	39	#define EM3027_REG_ALARM_MON 0x15
	40	#define EM3027_REG_ALARM_YEAR 0x16
	41
	42	static struct i2c_driver em3027_driver;
	43
	44	static int em3027_get_time(struct device dev, struct rtc_time tm)
	45	{
	46	struct i2c_client *client = to_i2c_client(dev);
	47
	48	unsigned char addr = EM3027_REG_WATCH_SEC;
	49	unsigned char buf[7];
	50
	51	struct i2c_msg msgs[] = {
	52	{client->addr, 0, 1, &addr}, /* setup read addr */
	53	{client->addr, I2C_M_RD, 7, buf}, /* read time/date */
	54	};
	55
	56	/* read time/date registers */
	57	if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
	58	dev_err(&client->dev, "%s: read error\n", __func__);
	59	return -EIO;
	60	}
	61
	62	tm->tm_sec = bcd2bin(buf[0]);
	63	tm->tm_min = bcd2bin(buf[1]);
	64	tm->tm_hour = bcd2bin(buf[2]);
	65	tm->tm_mday = bcd2bin(buf[3]);
	66	tm->tm_wday = bcd2bin(buf[4]);
	67	tm->tm_mon = bcd2bin(buf[5]);
	68	tm->tm_year = bcd2bin(buf[6]) + 100;
	69
	70	return 0;
	71	}
	72
	73	static int em3027_set_time(struct device dev, struct rtc_time tm)
	74	{
	75	struct i2c_client *client = to_i2c_client(dev);
	76	unsigned char buf[8];
	77
	78	struct i2c_msg msg = {
	79	client->addr, 0, 8, buf, /* write time/date */
	80	};
	81
82	buf[0] = EM3027_REG_WATCH_SEC;
83	buf[1] = bin2bcd(tm->tm_sec);
84	buf[2] = bin2bcd(tm->tm_min);
85	buf[3] = bin2bcd(tm->tm_hour);
86	buf[4] = bin2bcd(tm->tm_mday);
87	buf[5] = bin2bcd(tm->tm_wday);
88	buf[6] = bin2bcd(tm->tm_mon);
89	buf[7] = bin2bcd(tm->tm_year % 100);
90
91	/* write time/date registers */
92	if ((i2c_transfer(client->adapter, &msg, 1)) != 1) {
93	dev_err(&client->dev, "%s: write error\n", __func__);
94	return -EIO;
95	}
96
97	return 0;
98	}
99
100	static const struct rtc_class_ops em3027_rtc_ops = {
101	.read_time = em3027_get_time,
102	.set_time = em3027_set_time,
103	};
104
105	static int em3027_probe(struct i2c_client *client,
106	const struct i2c_device_id *id)
107	{
108	struct rtc_device *rtc;
109
110	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
111	return -ENODEV;
112
113	rtc = rtc_device_register(em3027_driver.driver.name, &client->dev,
114	&em3027_rtc_ops, THIS_MODULE);
115	if (IS_ERR(rtc))
116	return PTR_ERR(rtc);
117
118	i2c_set_clientdata(client, rtc);
119
120	return 0;
121	}
122
123	static int em3027_remove(struct i2c_client *client)
124	{
125	struct rtc_device *rtc = i2c_get_clientdata(client);
126
127	if (rtc)
128	rtc_device_unregister(rtc);
129
130	return 0;
131	}
132
133	static struct i2c_device_id em3027_id[] = {
134	{ "em3027", 0 },
135	{ }
136	};
137
138	static struct i2c_driver em3027_driver = {
139	.driver = {
140	.name = "rtc-em3027",
141	},
142	.probe = &em3027_probe,
143	.remove = &em3027_remove,
144	.id_table = em3027_id,
145	};
146
0abc9201	147	module_i2c_driver(em3027_driver);
ae3551f9 MR	148
	149	MODULE_AUTHOR("Mike Rapoport <[email protected]>");
	150	MODULE_DESCRIPTION("EM Microelectronic EM3027 RTC driver");
	151	MODULE_LICENSE("GPL");