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authorDavid Brownell <david-b@pacbell.net>2007-07-17 07:05:10 -0400
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-17 13:23:09 -0400
commitc065f35c17929067a367139d14e26897d60c7f6d (patch)
treee8c4c3c7bbf51e4b303a821f62c866a166f5e7f5 /drivers/rtc/rtc-ds1307.c
parentbe5f59f4b67fbd4de26802a291bbcc2c623302b7 (diff)
rtc-ds1307 becomes new-style i2c driver
Convert the rtc-ds1307 driver into a "new style" driver. Also improve probe() checks: be more correct about switching out of AM/PM mode, and issue a (debug) diagnostic when failing due to bogus register values. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Andrew Victor <andrew@sanpeople.com> Cc: Bill Gatliff <bgat@billgatliff.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kumar Gala <galak@gate.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
-rw-r--r--drivers/rtc/rtc-ds1307.c128
1 files changed, 53 insertions, 75 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 5306a1a5b873..5158a625671f 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -27,13 +27,8 @@
27 * This is currently a simple no-alarms driver. If your board has the 27 * This is currently a simple no-alarms driver. If your board has the
28 * alarm irq wired up on a ds1337 or ds1339, and you want to use that, 28 * alarm irq wired up on a ds1337 or ds1339, and you want to use that,
29 * then look at the rtc-rs5c372 driver for code to steal... 29 * then look at the rtc-rs5c372 driver for code to steal...
30 *
31 * If the I2C "force" mechanism is used, we assume the chip is a ds1337.
32 * (Much better would be board-specific tables of I2C devices, along with
33 * the platform_data drivers would use to sort such issues out.)
34 */ 30 */
35enum ds_type { 31enum ds_type {
36 unknown = 0,
37 ds_1307, 32 ds_1307,
38 ds_1337, 33 ds_1337,
39 ds_1338, 34 ds_1338,
@@ -43,11 +38,6 @@ enum ds_type {
43 // rs5c372 too? different address... 38 // rs5c372 too? different address...
44}; 39};
45 40
46static unsigned short normal_i2c[] = { 0x68, I2C_CLIENT_END };
47
48I2C_CLIENT_INSMOD;
49
50
51 41
52/* RTC registers don't differ much, except for the century flag */ 42/* RTC registers don't differ much, except for the century flag */
53#define DS1307_REG_SECS 0x00 /* 00-59 */ 43#define DS1307_REG_SECS 0x00 /* 00-59 */
@@ -55,6 +45,8 @@ I2C_CLIENT_INSMOD;
55# define DS1340_BIT_nEOSC 0x80 45# define DS1340_BIT_nEOSC 0x80
56#define DS1307_REG_MIN 0x01 /* 00-59 */ 46#define DS1307_REG_MIN 0x01 /* 00-59 */
57#define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */ 47#define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
48# define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
49# define DS1307_BIT_PM 0x20 /* in REG_HOUR */
58# define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */ 50# define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
59# define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */ 51# define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
60#define DS1307_REG_WDAY 0x03 /* 01-07 */ 52#define DS1307_REG_WDAY 0x03 /* 01-07 */
@@ -252,39 +244,27 @@ static const struct rtc_class_ops ds13xx_rtc_ops = {
252 244
253static struct i2c_driver ds1307_driver; 245static struct i2c_driver ds1307_driver;
254 246
255static int __devinit 247static int __devinit ds1307_probe(struct i2c_client *client)
256ds1307_detect(struct i2c_adapter *adapter, int address, int kind)
257{ 248{
258 struct ds1307 *ds1307; 249 struct ds1307 *ds1307;
259 int err = -ENODEV; 250 int err = -ENODEV;
260 struct i2c_client *client;
261 int tmp; 251 int tmp;
262 const struct chip_desc *chip; 252 const struct chip_desc *chip;
253 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
263 254
264 if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL))) { 255 chip = find_chip(client->name);
265 err = -ENOMEM; 256 if (!chip) {
266 goto exit; 257 dev_err(&client->dev, "unknown chip type '%s'\n",
258 client->name);
259 return -ENODEV;
267 } 260 }
268 261
269 /* REVISIT: pending driver model conversion, set up "client" 262 if (!i2c_check_functionality(adapter,
270 * ourselves, and use a hack to determine the RTC type (instead 263 I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
271 * of reading the client->name we're given) 264 return -EIO;
272 */ 265
273 client = &ds1307->dev; 266 if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL)))
274 client->addr = address; 267 return -ENOMEM;
275 client->adapter = adapter;
276 client->driver = &ds1307_driver;
277
278 /* HACK: "force" implies "needs ds1337-style-oscillator setup", and
279 * that's the only kind of chip setup we'll know about. Until the
280 * driver model conversion, here's where to add any board-specific
281 * code to say what kind of chip is present...
282 */
283 if (kind >= 0)
284 chip = find_chip("ds1337");
285 else
286 chip = find_chip("ds1307");
287 strlcpy(client->name, chip->name, I2C_NAME_SIZE);
288 268
289 ds1307->client = client; 269 ds1307->client = client;
290 i2c_set_clientdata(client, ds1307); 270 i2c_set_clientdata(client, ds1307);
@@ -378,94 +358,92 @@ read_rtc:
378 goto read_rtc; 358 goto read_rtc;
379 } 359 }
380 break; 360 break;
381 default: 361 case ds_1337:
362 case ds_1339:
382 break; 363 break;
383 } 364 }
384 365
385 tmp = ds1307->regs[DS1307_REG_SECS]; 366 tmp = ds1307->regs[DS1307_REG_SECS];
386 tmp = BCD2BIN(tmp & 0x7f); 367 tmp = BCD2BIN(tmp & 0x7f);
387 if (tmp > 60) 368 if (tmp > 60)
388 goto exit_free; 369 goto exit_bad;
389 tmp = BCD2BIN(ds1307->regs[DS1307_REG_MIN] & 0x7f); 370 tmp = BCD2BIN(ds1307->regs[DS1307_REG_MIN] & 0x7f);
390 if (tmp > 60) 371 if (tmp > 60)
391 goto exit_free; 372 goto exit_bad;
392 373
393 tmp = BCD2BIN(ds1307->regs[DS1307_REG_MDAY] & 0x3f); 374 tmp = BCD2BIN(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
394 if (tmp == 0 || tmp > 31) 375 if (tmp == 0 || tmp > 31)
395 goto exit_free; 376 goto exit_bad;
396 377
397 tmp = BCD2BIN(ds1307->regs[DS1307_REG_MONTH] & 0x1f); 378 tmp = BCD2BIN(ds1307->regs[DS1307_REG_MONTH] & 0x1f);
398 if (tmp == 0 || tmp > 12) 379 if (tmp == 0 || tmp > 12)
399 goto exit_free; 380 goto exit_bad;
400 381
401 /* force into in 24 hour mode (most chips) or
402 * disable century bit (ds1340)
403 *
404 * REVISIT forcing 24 hour mode can prevent multi-master
405 * configs from sharing this RTC ... don't do this.
406 * The clock needs to be reset after changing it, too...
407 */
408 tmp = ds1307->regs[DS1307_REG_HOUR]; 382 tmp = ds1307->regs[DS1307_REG_HOUR];
409 if (tmp & (1 << 6)) { 383 switch (ds1307->type) {
410 if (tmp & (1 << 5)) 384 case ds_1340:
411 tmp = BCD2BIN(tmp & 0x1f) + 12; 385 case m41t00:
412 else 386 /* NOTE: ignores century bits; fix before deploying
413 tmp = BCD2BIN(tmp); 387 * systems that will run through year 2100.
388 */
389 break;
390 default:
391 if (!(tmp & DS1307_BIT_12HR))
392 break;
393
394 /* Be sure we're in 24 hour mode. Multi-master systems
395 * take note...
396 */
397 tmp = BCD2BIN(tmp & 0x1f);
398 if (tmp == 12)
399 tmp = 0;
400 if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
401 tmp += 12;
414 i2c_smbus_write_byte_data(client, 402 i2c_smbus_write_byte_data(client,
415 DS1307_REG_HOUR, 403 DS1307_REG_HOUR,
416 BIN2BCD(tmp)); 404 BIN2BCD(tmp));
417 } 405 }
418 406
419 /* Tell the I2C layer a new client has arrived */
420 if ((err = i2c_attach_client(client)))
421 goto exit_free;
422
423 ds1307->rtc = rtc_device_register(client->name, &client->dev, 407 ds1307->rtc = rtc_device_register(client->name, &client->dev,
424 &ds13xx_rtc_ops, THIS_MODULE); 408 &ds13xx_rtc_ops, THIS_MODULE);
425 if (IS_ERR(ds1307->rtc)) { 409 if (IS_ERR(ds1307->rtc)) {
426 err = PTR_ERR(ds1307->rtc); 410 err = PTR_ERR(ds1307->rtc);
427 dev_err(&client->dev, 411 dev_err(&client->dev,
428 "unable to register the class device\n"); 412 "unable to register the class device\n");
429 goto exit_detach; 413 goto exit_free;
430 } 414 }
431 415
432 return 0; 416 return 0;
433 417
434exit_detach: 418exit_bad:
435 i2c_detach_client(client); 419 dev_dbg(&client->dev, "%s: %02x %02x %02x %02x %02x %02x %02x\n",
420 "bogus register",
421 ds1307->regs[0], ds1307->regs[1],
422 ds1307->regs[2], ds1307->regs[3],
423 ds1307->regs[4], ds1307->regs[5],
424 ds1307->regs[6]);
425
436exit_free: 426exit_free:
437 kfree(ds1307); 427 kfree(ds1307);
438exit:
439 return err; 428 return err;
440} 429}
441 430
442static int __devinit 431static int __devexit ds1307_remove(struct i2c_client *client)
443ds1307_attach_adapter(struct i2c_adapter *adapter)
444{
445 if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
446 return 0;
447 return i2c_probe(adapter, &addr_data, ds1307_detect);
448}
449
450static int __devexit ds1307_detach_client(struct i2c_client *client)
451{ 432{
452 int err;
453 struct ds1307 *ds1307 = i2c_get_clientdata(client); 433 struct ds1307 *ds1307 = i2c_get_clientdata(client);
454 434
455 rtc_device_unregister(ds1307->rtc); 435 rtc_device_unregister(ds1307->rtc);
456 if ((err = i2c_detach_client(client)))
457 return err;
458 kfree(ds1307); 436 kfree(ds1307);
459 return 0; 437 return 0;
460} 438}
461 439
462static struct i2c_driver ds1307_driver = { 440static struct i2c_driver ds1307_driver = {
463 .driver = { 441 .driver = {
464 .name = "ds1307", 442 .name = "rtc-ds1307",
465 .owner = THIS_MODULE, 443 .owner = THIS_MODULE,
466 }, 444 },
467 .attach_adapter = ds1307_attach_adapter, 445 .probe = ds1307_probe,
468 .detach_client = __devexit_p(ds1307_detach_client), 446 .remove = __devexit_p(ds1307_remove),
469}; 447};
470 448
471static int __init ds1307_init(void) 449static int __init ds1307_init(void)