| /* |
| * An I2C driver for the Ricoh RS5C372 RTC |
| * |
| * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net> |
| * Copyright (C) 2006 Tower Technologies |
| * |
| * 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> |
| |
| #define DRV_VERSION "0.2" |
| |
| /* Addresses to scan */ |
| static unsigned short normal_i2c[] = { /* 0x32,*/ I2C_CLIENT_END }; |
| |
| /* Insmod parameters */ |
| I2C_CLIENT_INSMOD; |
| |
| #define RS5C372_REG_SECS 0 |
| #define RS5C372_REG_MINS 1 |
| #define RS5C372_REG_HOURS 2 |
| #define RS5C372_REG_WDAY 3 |
| #define RS5C372_REG_DAY 4 |
| #define RS5C372_REG_MONTH 5 |
| #define RS5C372_REG_YEAR 6 |
| #define RS5C372_REG_TRIM 7 |
| |
| #define RS5C372_TRIM_XSL 0x80 |
| #define RS5C372_TRIM_MASK 0x7F |
| |
| #define RS5C372_REG_BASE 0 |
| |
| static int rs5c372_attach(struct i2c_adapter *adapter); |
| static int rs5c372_detach(struct i2c_client *client); |
| static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind); |
| |
| static struct i2c_driver rs5c372_driver = { |
| .driver = { |
| .name = "rs5c372", |
| }, |
| .attach_adapter = &rs5c372_attach, |
| .detach_client = &rs5c372_detach, |
| }; |
| |
| static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm) |
| { |
| unsigned char buf[7] = { RS5C372_REG_BASE }; |
| |
| /* this implements the 1st reading method, according |
| * to the datasheet. buf[0] is initialized with |
| * address ptr and transmission format register. |
| */ |
| struct i2c_msg msgs[] = { |
| { client->addr, 0, 1, buf }, |
| { client->addr, I2C_M_RD, 7, buf }, |
| }; |
| |
| if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { |
| dev_err(&client->dev, "%s: read error\n", __FUNCTION__); |
| return -EIO; |
| } |
| |
| tm->tm_sec = BCD2BIN(buf[RS5C372_REG_SECS] & 0x7f); |
| tm->tm_min = BCD2BIN(buf[RS5C372_REG_MINS] & 0x7f); |
| tm->tm_hour = BCD2BIN(buf[RS5C372_REG_HOURS] & 0x3f); |
| tm->tm_wday = BCD2BIN(buf[RS5C372_REG_WDAY] & 0x07); |
| tm->tm_mday = BCD2BIN(buf[RS5C372_REG_DAY] & 0x3f); |
| |
| /* tm->tm_mon is zero-based */ |
| tm->tm_mon = BCD2BIN(buf[RS5C372_REG_MONTH] & 0x1f) - 1; |
| |
| /* year is 1900 + tm->tm_year */ |
| tm->tm_year = BCD2BIN(buf[RS5C372_REG_YEAR]) + 100; |
| |
| dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " |
| "mday=%d, mon=%d, year=%d, wday=%d\n", |
| __FUNCTION__, |
| tm->tm_sec, tm->tm_min, tm->tm_hour, |
| tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); |
| |
| return 0; |
| } |
| |
| static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm) |
| { |
| unsigned char buf[8] = { RS5C372_REG_BASE }; |
| |
| dev_dbg(&client->dev, |
| "%s: secs=%d, mins=%d, hours=%d " |
| "mday=%d, mon=%d, year=%d, wday=%d\n", |
| __FUNCTION__, tm->tm_sec, tm->tm_min, tm->tm_hour, |
| tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); |
| |
| buf[1] = BIN2BCD(tm->tm_sec); |
| buf[2] = BIN2BCD(tm->tm_min); |
| buf[3] = BIN2BCD(tm->tm_hour); |
| buf[4] = BIN2BCD(tm->tm_wday); |
| buf[5] = BIN2BCD(tm->tm_mday); |
| buf[6] = BIN2BCD(tm->tm_mon + 1); |
| buf[7] = BIN2BCD(tm->tm_year - 100); |
| |
| if ((i2c_master_send(client, buf, 8)) != 8) { |
| dev_err(&client->dev, "%s: write error\n", __FUNCTION__); |
| return -EIO; |
| } |
| |
| return 0; |
| } |
| |
| static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim) |
| { |
| unsigned char buf = RS5C372_REG_TRIM; |
| |
| struct i2c_msg msgs[] = { |
| { client->addr, 0, 1, &buf }, |
| { client->addr, I2C_M_RD, 1, &buf }, |
| }; |
| |
| if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { |
| dev_err(&client->dev, "%s: read error\n", __FUNCTION__); |
| return -EIO; |
| } |
| |
| dev_dbg(&client->dev, "%s: raw trim=%x\n", __FUNCTION__, *trim); |
| |
| if (osc) |
| *osc = (buf & RS5C372_TRIM_XSL) ? 32000 : 32768; |
| |
| if (trim) |
| *trim = buf & RS5C372_TRIM_MASK; |
| |
| return 0; |
| } |
| |
| static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| return rs5c372_get_datetime(to_i2c_client(dev), tm); |
| } |
| |
| static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| return rs5c372_set_datetime(to_i2c_client(dev), tm); |
| } |
| |
| static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq) |
| { |
| int err, osc, trim; |
| |
| err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim); |
| if (err == 0) { |
| seq_printf(seq, "%d.%03d KHz\n", osc / 1000, osc % 1000); |
| seq_printf(seq, "trim\t: %d\n", trim); |
| } |
| |
| return 0; |
| } |
| |
| static const struct rtc_class_ops rs5c372_rtc_ops = { |
| .proc = rs5c372_rtc_proc, |
| .read_time = rs5c372_rtc_read_time, |
| .set_time = rs5c372_rtc_set_time, |
| }; |
| |
| static ssize_t rs5c372_sysfs_show_trim(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| int err, trim; |
| |
| err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim); |
| if (err) |
| return err; |
| |
| return sprintf(buf, "0x%2x\n", trim); |
| } |
| static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL); |
| |
| static ssize_t rs5c372_sysfs_show_osc(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| int err, osc; |
| |
| err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL); |
| if (err) |
| return err; |
| |
| return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000); |
| } |
| static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL); |
| |
| static int rs5c372_attach(struct i2c_adapter *adapter) |
| { |
| return i2c_probe(adapter, &addr_data, rs5c372_probe); |
| } |
| |
| static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind) |
| { |
| int err = 0; |
| struct i2c_client *client; |
| struct rtc_device *rtc; |
| |
| dev_dbg(&adapter->dev, "%s\n", __FUNCTION__); |
| |
| if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) { |
| err = -ENODEV; |
| goto exit; |
| } |
| |
| if (!(client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL))) { |
| err = -ENOMEM; |
| goto exit; |
| } |
| |
| /* I2C client */ |
| client->addr = address; |
| client->driver = &rs5c372_driver; |
| client->adapter = adapter; |
| |
| strlcpy(client->name, rs5c372_driver.driver.name, I2C_NAME_SIZE); |
| |
| /* Inform the i2c layer */ |
| if ((err = i2c_attach_client(client))) |
| goto exit_kfree; |
| |
| dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); |
| |
| rtc = rtc_device_register(rs5c372_driver.driver.name, &client->dev, |
| &rs5c372_rtc_ops, THIS_MODULE); |
| |
| if (IS_ERR(rtc)) { |
| err = PTR_ERR(rtc); |
| goto exit_detach; |
| } |
| |
| i2c_set_clientdata(client, rtc); |
| |
| device_create_file(&client->dev, &dev_attr_trim); |
| device_create_file(&client->dev, &dev_attr_osc); |
| |
| return 0; |
| |
| exit_detach: |
| i2c_detach_client(client); |
| |
| exit_kfree: |
| kfree(client); |
| |
| exit: |
| return err; |
| } |
| |
| static int rs5c372_detach(struct i2c_client *client) |
| { |
| int err; |
| struct rtc_device *rtc = i2c_get_clientdata(client); |
| |
| if (rtc) |
| rtc_device_unregister(rtc); |
| |
| if ((err = i2c_detach_client(client))) |
| return err; |
| |
| kfree(client); |
| |
| return 0; |
| } |
| |
| static __init int rs5c372_init(void) |
| { |
| return i2c_add_driver(&rs5c372_driver); |
| } |
| |
| static __exit void rs5c372_exit(void) |
| { |
| i2c_del_driver(&rs5c372_driver); |
| } |
| |
| module_init(rs5c372_init); |
| module_exit(rs5c372_exit); |
| |
| MODULE_AUTHOR( |
| "Pavel Mironchik <pmironchik@optifacio.net>, " |
| "Alessandro Zummo <a.zummo@towertech.it>"); |
| MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_VERSION(DRV_VERSION); |