/* * 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 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);