Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 1 | /* |
| 2 | * An I2C driver for the Ricoh RS5C372 RTC |
| 3 | * |
| 4 | * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net> |
| 5 | * Copyright (C) 2006 Tower Technologies |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/i2c.h> |
| 13 | #include <linux/rtc.h> |
| 14 | #include <linux/bcd.h> |
| 15 | |
| 16 | #define DRV_VERSION "0.2" |
| 17 | |
| 18 | /* Addresses to scan */ |
| 19 | static unsigned short normal_i2c[] = { /* 0x32,*/ I2C_CLIENT_END }; |
| 20 | |
| 21 | /* Insmod parameters */ |
| 22 | I2C_CLIENT_INSMOD; |
| 23 | |
| 24 | #define RS5C372_REG_SECS 0 |
| 25 | #define RS5C372_REG_MINS 1 |
| 26 | #define RS5C372_REG_HOURS 2 |
| 27 | #define RS5C372_REG_WDAY 3 |
| 28 | #define RS5C372_REG_DAY 4 |
| 29 | #define RS5C372_REG_MONTH 5 |
| 30 | #define RS5C372_REG_YEAR 6 |
| 31 | #define RS5C372_REG_TRIM 7 |
| 32 | |
| 33 | #define RS5C372_TRIM_XSL 0x80 |
| 34 | #define RS5C372_TRIM_MASK 0x7F |
| 35 | |
| 36 | #define RS5C372_REG_BASE 0 |
| 37 | |
| 38 | static int rs5c372_attach(struct i2c_adapter *adapter); |
| 39 | static int rs5c372_detach(struct i2c_client *client); |
| 40 | static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind); |
| 41 | |
| 42 | static struct i2c_driver rs5c372_driver = { |
| 43 | .driver = { |
| 44 | .name = "rs5c372", |
| 45 | }, |
| 46 | .attach_adapter = &rs5c372_attach, |
| 47 | .detach_client = &rs5c372_detach, |
| 48 | }; |
| 49 | |
| 50 | static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm) |
| 51 | { |
| 52 | unsigned char buf[7] = { RS5C372_REG_BASE }; |
| 53 | |
| 54 | /* this implements the 1st reading method, according |
| 55 | * to the datasheet. buf[0] is initialized with |
| 56 | * address ptr and transmission format register. |
| 57 | */ |
| 58 | struct i2c_msg msgs[] = { |
| 59 | { client->addr, 0, 1, buf }, |
| 60 | { client->addr, I2C_M_RD, 7, buf }, |
| 61 | }; |
| 62 | |
| 63 | if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { |
| 64 | dev_err(&client->dev, "%s: read error\n", __FUNCTION__); |
| 65 | return -EIO; |
| 66 | } |
| 67 | |
| 68 | tm->tm_sec = BCD2BIN(buf[RS5C372_REG_SECS] & 0x7f); |
| 69 | tm->tm_min = BCD2BIN(buf[RS5C372_REG_MINS] & 0x7f); |
| 70 | tm->tm_hour = BCD2BIN(buf[RS5C372_REG_HOURS] & 0x3f); |
| 71 | tm->tm_wday = BCD2BIN(buf[RS5C372_REG_WDAY] & 0x07); |
| 72 | tm->tm_mday = BCD2BIN(buf[RS5C372_REG_DAY] & 0x3f); |
| 73 | |
| 74 | /* tm->tm_mon is zero-based */ |
| 75 | tm->tm_mon = BCD2BIN(buf[RS5C372_REG_MONTH] & 0x1f) - 1; |
| 76 | |
| 77 | /* year is 1900 + tm->tm_year */ |
| 78 | tm->tm_year = BCD2BIN(buf[RS5C372_REG_YEAR]) + 100; |
| 79 | |
| 80 | dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " |
| 81 | "mday=%d, mon=%d, year=%d, wday=%d\n", |
| 82 | __FUNCTION__, |
| 83 | tm->tm_sec, tm->tm_min, tm->tm_hour, |
| 84 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); |
| 85 | |
| 86 | return 0; |
| 87 | } |
| 88 | |
| 89 | static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm) |
| 90 | { |
| 91 | unsigned char buf[8] = { RS5C372_REG_BASE }; |
| 92 | |
| 93 | dev_dbg(&client->dev, |
| 94 | "%s: secs=%d, mins=%d, hours=%d ", |
| 95 | "mday=%d, mon=%d, year=%d, wday=%d\n", |
| 96 | __FUNCTION__, tm->tm_sec, tm->tm_min, tm->tm_hour, |
| 97 | tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); |
| 98 | |
| 99 | buf[1] = BIN2BCD(tm->tm_sec); |
| 100 | buf[2] = BIN2BCD(tm->tm_min); |
| 101 | buf[3] = BIN2BCD(tm->tm_hour); |
| 102 | buf[4] = BIN2BCD(tm->tm_wday); |
| 103 | buf[5] = BIN2BCD(tm->tm_mday); |
| 104 | buf[6] = BIN2BCD(tm->tm_mon + 1); |
| 105 | buf[7] = BIN2BCD(tm->tm_year - 100); |
| 106 | |
| 107 | if ((i2c_master_send(client, buf, 8)) != 8) { |
| 108 | dev_err(&client->dev, "%s: write error\n", __FUNCTION__); |
| 109 | return -EIO; |
| 110 | } |
| 111 | |
| 112 | return 0; |
| 113 | } |
| 114 | |
| 115 | static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim) |
| 116 | { |
| 117 | unsigned char buf = RS5C372_REG_TRIM; |
| 118 | |
| 119 | struct i2c_msg msgs[] = { |
| 120 | { client->addr, 0, 1, &buf }, |
| 121 | { client->addr, I2C_M_RD, 1, &buf }, |
| 122 | }; |
| 123 | |
| 124 | if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { |
| 125 | dev_err(&client->dev, "%s: read error\n", __FUNCTION__); |
| 126 | return -EIO; |
| 127 | } |
| 128 | |
| 129 | dev_dbg(&client->dev, "%s: raw trim=%x\n", __FUNCTION__, trim); |
| 130 | |
| 131 | if (osc) |
| 132 | *osc = (buf & RS5C372_TRIM_XSL) ? 32000 : 32768; |
| 133 | |
| 134 | if (trim) |
| 135 | *trim = buf & RS5C372_TRIM_MASK; |
| 136 | |
| 137 | return 0; |
| 138 | } |
| 139 | |
| 140 | static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| 141 | { |
| 142 | return rs5c372_get_datetime(to_i2c_client(dev), tm); |
| 143 | } |
| 144 | |
| 145 | static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| 146 | { |
| 147 | return rs5c372_set_datetime(to_i2c_client(dev), tm); |
| 148 | } |
| 149 | |
| 150 | static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq) |
| 151 | { |
| 152 | int err, osc, trim; |
| 153 | |
Alessandro Zummo | adfb434 | 2006-04-10 22:54:43 -0700 | [diff] [blame] | 154 | err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim); |
| 155 | if (err == 0) { |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 156 | seq_printf(seq, "%d.%03d KHz\n", osc / 1000, osc % 1000); |
| 157 | seq_printf(seq, "trim\t: %d\n", trim); |
| 158 | } |
| 159 | |
| 160 | return 0; |
| 161 | } |
| 162 | |
| 163 | static struct rtc_class_ops rs5c372_rtc_ops = { |
| 164 | .proc = rs5c372_rtc_proc, |
| 165 | .read_time = rs5c372_rtc_read_time, |
| 166 | .set_time = rs5c372_rtc_set_time, |
| 167 | }; |
| 168 | |
| 169 | static ssize_t rs5c372_sysfs_show_trim(struct device *dev, |
| 170 | struct device_attribute *attr, char *buf) |
| 171 | { |
Alessandro Zummo | 8289607 | 2006-04-10 22:54:44 -0700 | [diff] [blame] | 172 | int err, trim; |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 173 | |
Alessandro Zummo | 8289607 | 2006-04-10 22:54:44 -0700 | [diff] [blame] | 174 | err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim); |
| 175 | if (err) |
| 176 | return err; |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 177 | |
Alessandro Zummo | 8289607 | 2006-04-10 22:54:44 -0700 | [diff] [blame] | 178 | return sprintf(buf, "0x%2x\n", trim); |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 179 | } |
| 180 | static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL); |
| 181 | |
| 182 | static ssize_t rs5c372_sysfs_show_osc(struct device *dev, |
| 183 | struct device_attribute *attr, char *buf) |
| 184 | { |
Alessandro Zummo | 8289607 | 2006-04-10 22:54:44 -0700 | [diff] [blame] | 185 | int err, osc; |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 186 | |
Alessandro Zummo | 8289607 | 2006-04-10 22:54:44 -0700 | [diff] [blame] | 187 | err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL); |
| 188 | if (err) |
| 189 | return err; |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 190 | |
Alessandro Zummo | 8289607 | 2006-04-10 22:54:44 -0700 | [diff] [blame] | 191 | return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000); |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 192 | } |
| 193 | static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL); |
| 194 | |
| 195 | static int rs5c372_attach(struct i2c_adapter *adapter) |
| 196 | { |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 197 | return i2c_probe(adapter, &addr_data, rs5c372_probe); |
| 198 | } |
| 199 | |
| 200 | static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind) |
| 201 | { |
| 202 | int err = 0; |
| 203 | struct i2c_client *client; |
| 204 | struct rtc_device *rtc; |
| 205 | |
| 206 | dev_dbg(&adapter->dev, "%s\n", __FUNCTION__); |
| 207 | |
| 208 | if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) { |
| 209 | err = -ENODEV; |
| 210 | goto exit; |
| 211 | } |
| 212 | |
| 213 | if (!(client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL))) { |
| 214 | err = -ENOMEM; |
| 215 | goto exit; |
| 216 | } |
| 217 | |
| 218 | /* I2C client */ |
| 219 | client->addr = address; |
| 220 | client->driver = &rs5c372_driver; |
| 221 | client->adapter = adapter; |
| 222 | |
| 223 | strlcpy(client->name, rs5c372_driver.driver.name, I2C_NAME_SIZE); |
| 224 | |
| 225 | /* Inform the i2c layer */ |
| 226 | if ((err = i2c_attach_client(client))) |
| 227 | goto exit_kfree; |
| 228 | |
| 229 | dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); |
| 230 | |
| 231 | rtc = rtc_device_register(rs5c372_driver.driver.name, &client->dev, |
| 232 | &rs5c372_rtc_ops, THIS_MODULE); |
| 233 | |
| 234 | if (IS_ERR(rtc)) { |
| 235 | err = PTR_ERR(rtc); |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 236 | goto exit_detach; |
| 237 | } |
| 238 | |
| 239 | i2c_set_clientdata(client, rtc); |
| 240 | |
| 241 | device_create_file(&client->dev, &dev_attr_trim); |
| 242 | device_create_file(&client->dev, &dev_attr_osc); |
| 243 | |
| 244 | return 0; |
| 245 | |
| 246 | exit_detach: |
| 247 | i2c_detach_client(client); |
| 248 | |
| 249 | exit_kfree: |
| 250 | kfree(client); |
| 251 | |
| 252 | exit: |
| 253 | return err; |
| 254 | } |
| 255 | |
| 256 | static int rs5c372_detach(struct i2c_client *client) |
| 257 | { |
| 258 | int err; |
| 259 | struct rtc_device *rtc = i2c_get_clientdata(client); |
| 260 | |
Alessandro Zummo | 7520b94 | 2006-03-27 01:16:45 -0800 | [diff] [blame] | 261 | if (rtc) |
| 262 | rtc_device_unregister(rtc); |
| 263 | |
| 264 | if ((err = i2c_detach_client(client))) |
| 265 | return err; |
| 266 | |
| 267 | kfree(client); |
| 268 | |
| 269 | return 0; |
| 270 | } |
| 271 | |
| 272 | static __init int rs5c372_init(void) |
| 273 | { |
| 274 | return i2c_add_driver(&rs5c372_driver); |
| 275 | } |
| 276 | |
| 277 | static __exit void rs5c372_exit(void) |
| 278 | { |
| 279 | i2c_del_driver(&rs5c372_driver); |
| 280 | } |
| 281 | |
| 282 | module_init(rs5c372_init); |
| 283 | module_exit(rs5c372_exit); |
| 284 | |
| 285 | MODULE_AUTHOR( |
| 286 | "Pavel Mironchik <pmironchik@optifacio.net>, " |
| 287 | "Alessandro Zummo <a.zummo@towertech.it>"); |
| 288 | MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver"); |
| 289 | MODULE_LICENSE("GPL"); |
| 290 | MODULE_VERSION(DRV_VERSION); |