drivers/i2c/chips/rtc8564.c

   1 /*
   2  *  linux/drivers/i2c/chips/rtc8564.c
   3  *
   4  *  Copyright (C) 2002-2004 Stefan Eletzhofer
   5  *
   6  *      based on linux/drivers/acron/char/pcf8583.c
   7  *  Copyright (C) 2000 Russell King
   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  * Driver for system3's EPSON RTC 8564 chip
  14  */
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/i2c.h>
  18 #include <linux/slab.h>
  19 #include <linux/string.h>
  20 #include <linux/rtc.h>          /* get the user-level API */
  21 #include <linux/init.h>
  22 #include <linux/init.h>
  23
  24 #include "rtc8564.h"
  25
  26 #ifdef DEBUG
  27 # define _DBG(x, fmt, args...) do{ if (debug>=x) printk(KERN_DEBUG"%s: " fmt "\n", __FUNCTION__, ##args); } while(0);
  28 #else
  29 # define _DBG(x, fmt, args...) do { } while(0);
  30 #endif
  31
  32 #define _DBGRTCTM(x, rtctm) if (debug>=x) printk("%s: secs=%d, mins=%d, hours=%d, mday=%d, " \
  33                         "mon=%d, year=%d, wday=%d VL=%d\n", __FUNCTION__, \
  34                         (rtctm).secs, (rtctm).mins, (rtctm).hours, (rtctm).mday, \
  35                         (rtctm).mon, (rtctm).year, (rtctm).wday, (rtctm).vl);
  36
  37 struct rtc8564_data {
  38         struct i2c_client client;
  39         u16 ctrl;
  40 };
  41
  42 static inline u8 _rtc8564_ctrl1(struct i2c_client *client)
  43 {
  44         struct rtc8564_data *data = i2c_get_clientdata(client);
  45         return data->ctrl & 0xff;
  46 }
  47 static inline u8 _rtc8564_ctrl2(struct i2c_client *client)
  48 {
  49         struct rtc8564_data *data = i2c_get_clientdata(client);
  50         return (data->ctrl & 0xff00) >> 8;
  51 }
  52
  53 #define CTRL1(c) _rtc8564_ctrl1(c)
  54 #define CTRL2(c) _rtc8564_ctrl2(c)
  55
  56 #define BCD_TO_BIN(val) (((val)&15) + ((val)>>4)*10)
  57 #define BIN_TO_BCD(val) ((((val)/10)<<4) + (val)%10)
  58
  59 static int debug;;
  60 module_param(debug, int, S_IRUGO | S_IWUSR);
  61
  62 static struct i2c_driver rtc8564_driver;
  63
  64 static unsigned short ignore[] = { I2C_CLIENT_END };
  65 static unsigned short normal_addr[] = { 0x51, I2C_CLIENT_END };
  66
  67 static struct i2c_client_address_data addr_data = {
  68         .normal_i2c             = normal_addr,
  69         .normal_i2c_range       = ignore,
  70         .probe                  = ignore,
  71         .probe_range            = ignore,
  72         .ignore                 = ignore,
  73         .ignore_range           = ignore,
  74         .force                  = ignore,
  75 };
  76
  77 static int rtc8564_read_mem(struct i2c_client *client, struct mem *mem);
  78 static int rtc8564_write_mem(struct i2c_client *client, struct mem *mem);
  79
  80 static int rtc8564_read(struct i2c_client *client, unsigned char adr,
  81                         unsigned char *buf, unsigned char len)
  82 {
  83         int ret = -EIO;
  84         unsigned char addr[1] = { adr };
  85         struct i2c_msg msgs[2] = {
  86                 {client->addr, 0, 1, addr},
  87                 {client->addr, I2C_M_RD, len, buf}
  88         };
  89
  90         _DBG(1, "client=%p, adr=%d, buf=%p, len=%d", client, adr, buf, len);
  91
  92         if (!buf) {
  93                 ret = -EINVAL;
  94                 goto done;
  95         }
  96
  97         ret = i2c_transfer(client->adapter, msgs, 2);
  98         if (ret == 2) {
  99                 ret = 0;
 100         }
 101
 102 done:
 103         return ret;
 104 }
 105
 106 static int rtc8564_write(struct i2c_client *client, unsigned char adr,
 107                          unsigned char *data, unsigned char len)
 108 {
 109         int ret = 0;
 110         unsigned char _data[16];
 111         struct i2c_msg wr;
 112         int i;
 113
 114         if (!data || len > 15) {
 115                 ret = -EINVAL;
 116                 goto done;
 117         }
 118
 119         _DBG(1, "client=%p, adr=%d, buf=%p, len=%d", client, adr, data, len);
 120
 121         _data[0] = adr;
 122         for (i = 0; i < len; i++) {
 123                 _data[i + 1] = data[i];
 124                 _DBG(5, "data[%d] = 0x%02x (%d)", i, data[i], data[i]);
 125         }
 126
 127         wr.addr = client->addr;
 128         wr.flags = 0;
 129         wr.len = len + 1;
 130         wr.buf = _data;
 131
 132         ret = i2c_transfer(client->adapter, &wr, 1);
 133         if (ret == 1) {
 134                 ret = 0;
 135         }
 136
 137 done:
 138         return ret;
 139 }
 140
 141 static int rtc8564_attach(struct i2c_adapter *adap, int addr, int kind)
 142 {
 143         int ret;
 144         struct i2c_client *new_client;
 145         struct rtc8564_data *d;
 146         unsigned char data[10];
 147         unsigned char ad[1] = { 0 };
 148         struct i2c_msg ctrl_wr[1] = {
 149                 {addr, 0, 2, data}
 150         };
 151         struct i2c_msg ctrl_rd[2] = {
 152                 {addr, 0, 1, ad},
 153                 {addr, I2C_M_RD, 2, data}
 154         };
 155
 156         d = kmalloc(sizeof(struct rtc8564_data), GFP_KERNEL);
 157         if (!d) {
 158                 ret = -ENOMEM;
 159                 goto done;
 160         }
 161         memset(d, 0, sizeof(struct rtc8564_data));
 162         new_client = &d->client;
 163
 164         strlcpy(new_client->name, "RTC8564", I2C_NAME_SIZE);
 165         i2c_set_clientdata(new_client, d);
 166         new_client->flags = I2C_CLIENT_ALLOW_USE | I2C_DF_NOTIFY;
 167         new_client->addr = addr;
 168         new_client->adapter = adap;
 169         new_client->driver = &rtc8564_driver;
 170
 171         _DBG(1, "client=%p", new_client);
 172
 173         /* init ctrl1 reg */
 174         data[0] = 0;
 175         data[1] = 0;
 176         ret = i2c_transfer(new_client->adapter, ctrl_wr, 1);
 177         if (ret != 1) {
 178                 printk(KERN_INFO "rtc8564: cant init ctrl1\n");
 179                 ret = -ENODEV;
 180                 goto done;
 181         }
 182
 183         /* read back ctrl1 and ctrl2 */
 184         ret = i2c_transfer(new_client->adapter, ctrl_rd, 2);
 185         if (ret != 2) {
 186                 printk(KERN_INFO "rtc8564: cant read ctrl\n");
 187                 ret = -ENODEV;
 188                 goto done;
 189         }
 190
 191         d->ctrl = data[0] | (data[1] << 8);
 192
 193         _DBG(1, "RTC8564_REG_CTRL1=%02x, RTC8564_REG_CTRL2=%02x",
 194              data[0], data[1]);
 195
 196         ret = i2c_attach_client(new_client);
 197 done:
 198         if (ret) {
 199                 kfree(d);
 200         }
 201         return ret;
 202 }
 203
 204 static int rtc8564_probe(struct i2c_adapter *adap)
 205 {
 206         return i2c_probe(adap, &addr_data, rtc8564_attach);
 207 }
 208
 209 static int rtc8564_detach(struct i2c_client *client)
 210 {
 211         i2c_detach_client(client);
 212         kfree(i2c_get_clientdata(client));
 213         return 0;
 214 }
 215
 216 static int rtc8564_get_datetime(struct i2c_client *client, struct rtc_tm *dt)
 217 {
 218         int ret = -EIO;
 219         unsigned char buf[15];
 220
 221         _DBG(1, "client=%p, dt=%p", client, dt);
 222
 223         if (!dt)
 224                 return -EINVAL;
 225
 226         memset(buf, 0, sizeof(buf));
 227
 228         ret = rtc8564_read(client, 0, buf, 15);
 229         if (ret)
 230                 return ret;
 231
 232         /* century stored in minute alarm reg */
 233         dt->year = BCD_TO_BIN(buf[RTC8564_REG_YEAR]);
 234         dt->year += 100 * BCD_TO_BIN(buf[RTC8564_REG_AL_MIN] & 0x3f);
 235         dt->mday = BCD_TO_BIN(buf[RTC8564_REG_DAY] & 0x3f);
 236         dt->wday = BCD_TO_BIN(buf[RTC8564_REG_WDAY] & 7);
 237         dt->mon = BCD_TO_BIN(buf[RTC8564_REG_MON_CENT] & 0x1f);
 238
 239         dt->secs = BCD_TO_BIN(buf[RTC8564_REG_SEC] & 0x7f);
 240         dt->vl = (buf[RTC8564_REG_SEC] & 0x80) == 0x80;
 241         dt->mins = BCD_TO_BIN(buf[RTC8564_REG_MIN] & 0x7f);
 242         dt->hours = BCD_TO_BIN(buf[RTC8564_REG_HR] & 0x3f);
 243
 244         _DBGRTCTM(2, *dt);
 245
 246         return 0;
 247 }
 248
 249 static int
 250 rtc8564_set_datetime(struct i2c_client *client, struct rtc_tm *dt, int datetoo)
 251 {
 252         int ret, len = 5;
 253         unsigned char buf[15];
 254
 255         _DBG(1, "client=%p, dt=%p", client, dt);
 256
 257         if (!dt)
 258                 return -EINVAL;
 259
 260         _DBGRTCTM(2, *dt);
 261
 262         buf[RTC8564_REG_CTRL1] = CTRL1(client) | RTC8564_CTRL1_STOP;
 263         buf[RTC8564_REG_CTRL2] = CTRL2(client);
 264         buf[RTC8564_REG_SEC] = BIN_TO_BCD(dt->secs);
 265         buf[RTC8564_REG_MIN] = BIN_TO_BCD(dt->mins);
 266         buf[RTC8564_REG_HR] = BIN_TO_BCD(dt->hours);
 267
 268         if (datetoo) {
 269                 len += 5;
 270                 buf[RTC8564_REG_DAY] = BIN_TO_BCD(dt->mday);
 271                 buf[RTC8564_REG_WDAY] = BIN_TO_BCD(dt->wday);
 272                 buf[RTC8564_REG_MON_CENT] = BIN_TO_BCD(dt->mon) & 0x1f;
 273                 /* century stored in minute alarm reg */
 274                 buf[RTC8564_REG_YEAR] = BIN_TO_BCD(dt->year % 100);
 275                 buf[RTC8564_REG_AL_MIN] = BIN_TO_BCD(dt->year / 100);
 276         }
 277
 278         ret = rtc8564_write(client, 0, buf, len);
 279         if (ret) {
 280                 _DBG(1, "error writing data! %d", ret);
 281         }
 282
 283         buf[RTC8564_REG_CTRL1] = CTRL1(client);
 284         ret = rtc8564_write(client, 0, buf, 1);
 285         if (ret) {
 286                 _DBG(1, "error writing data! %d", ret);
 287         }
 288
 289         return ret;
 290 }
 291
 292 static int rtc8564_get_ctrl(struct i2c_client *client, unsigned int *ctrl)
 293 {
 294         struct rtc8564_data *data = i2c_get_clientdata(client);
 295
 296         if (!ctrl)
 297                 return -1;
 298
 299         *ctrl = data->ctrl;
 300         return 0;
 301 }
 302
 303 static int rtc8564_set_ctrl(struct i2c_client *client, unsigned int *ctrl)
 304 {
 305         struct rtc8564_data *data = i2c_get_clientdata(client);
 306         unsigned char buf[2];
 307
 308         if (!ctrl)
 309                 return -1;
 310
 311         buf[0] = *ctrl & 0xff;
 312         buf[1] = (*ctrl & 0xff00) >> 8;
 313         data->ctrl = *ctrl;
 314
 315         return rtc8564_write(client, 0, buf, 2);
 316 }
 317
 318 static int rtc8564_read_mem(struct i2c_client *client, struct mem *mem)
 319 {
 320
 321         if (!mem)
 322                 return -EINVAL;
 323
 324         return rtc8564_read(client, mem->loc, mem->data, mem->nr);
 325 }
 326
 327 static int rtc8564_write_mem(struct i2c_client *client, struct mem *mem)
 328 {
 329
 330         if (!mem)
 331                 return -EINVAL;
 332
 333         return rtc8564_write(client, mem->loc, mem->data, mem->nr);
 334 }
 335
 336 static int
 337 rtc8564_command(struct i2c_client *client, unsigned int cmd, void *arg)
 338 {
 339
 340         _DBG(1, "cmd=%d", cmd);
 341
 342         switch (cmd) {
 343         case RTC_GETDATETIME:
 344                 return rtc8564_get_datetime(client, arg);
 345
 346         case RTC_SETTIME:
 347                 return rtc8564_set_datetime(client, arg, 0);
 348
 349         case RTC_SETDATETIME:
 350                 return rtc8564_set_datetime(client, arg, 1);
 351
 352         case RTC_GETCTRL:
 353                 return rtc8564_get_ctrl(client, arg);
 354
 355         case RTC_SETCTRL:
 356                 return rtc8564_set_ctrl(client, arg);
 357
 358         case MEM_READ:
 359                 return rtc8564_read_mem(client, arg);
 360
 361         case MEM_WRITE:
 362                 return rtc8564_write_mem(client, arg);
 363
 364         default:
 365                 return -EINVAL;
 366         }
 367 }
 368
 369 static struct i2c_driver rtc8564_driver = {
 370         .owner          = THIS_MODULE,
 371         .name           = "RTC8564",
 372         .id             = I2C_DRIVERID_RTC8564,
 373         .flags          = I2C_DF_NOTIFY,
 374         .attach_adapter = rtc8564_probe,
 375         .detach_client  = rtc8564_detach,
 376         .command        = rtc8564_command
 377 };
 378
 379 static __init int rtc8564_init(void)
 380 {
 381         return i2c_add_driver(&rtc8564_driver);
 382 }
 383
 384 static __exit void rtc8564_exit(void)
 385 {
 386         i2c_del_driver(&rtc8564_driver);
 387 }
 388
 389 MODULE_AUTHOR("Stefan Eletzhofer <Stefan.Eletzhofer@eletztrick.de>");
 390 MODULE_DESCRIPTION("EPSON RTC8564 Driver");
 391 MODULE_LICENSE("GPL");
 392
 393 module_init(rtc8564_init);
 394 module_exit(rtc8564_exit);