diff options
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
| -rw-r--r-- | drivers/rtc/rtc-ds1307.c | 37 |
1 files changed, 24 insertions, 13 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index d4543e8730cb..84ab971978cf 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -20,7 +20,8 @@ -/* We can't determine type by probing, but if we expect pre-Linux code +/* + * We can't determine type by probing, but if we expect pre-Linux code * to have set the chip up as a clock (turning on the oscillator and * setting the date and time), Linux can ignore the non-clock features. * That's a natural job for a factory or repair bench. @@ -37,7 +38,7 @@ enum ds_type { mcp7941x, rx_8025, last_ds_type /* always last */ - // rs5c372 too? different address... + /* rs5c372 too? different address... */ }; @@ -59,7 +60,8 @@ enum ds_type { # define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */ #define DS1307_REG_YEAR 0x06 /* 00-99 */ -/* Other registers (control, status, alarms, trickle charge, NVRAM, etc) +/* + * Other registers (control, status, alarms, trickle charge, NVRAM, etc) * start at 7, and they differ a LOT. Only control and status matter for * basic RTC date and time functionality; be careful using them. */ @@ -366,6 +368,11 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t) | DS1340_BIT_CENTURY; break; case mcp7941x: + /* + * these bits were cleared when preparing the date/time + * values and need to be set again before writing the + * buffer out to the device. + */ buf[DS1307_REG_SECS] |= MCP7941X_BIT_ST; buf[DS1307_REG_WDAY] |= MCP7941X_BIT_VBATEN; break; @@ -411,7 +418,8 @@ static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t) ds1307->regs[6], ds1307->regs[7], ds1307->regs[8]); - /* report alarm time (ALARM1); assume 24 hour and day-of-month modes, + /* + * report alarm time (ALARM1); assume 24 hour and day-of-month modes, * and that all four fields are checked matches */ t->time.tm_sec = bcd2bin(ds1307->regs[0] & 0x7f); @@ -439,7 +447,7 @@ static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t) static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t) { - struct i2c_client *client = to_i2c_client(dev); + struct i2c_client *client = to_i2c_client(dev); struct ds1307 *ds1307 = i2c_get_clientdata(client); unsigned char *buf = ds1307->regs; u8 control, status; @@ -602,8 +610,6 @@ static struct bin_attribute nvram = { /*----------------------------------------------------------------------*/ -static struct i2c_driver ds1307_driver; - static int __devinit ds1307_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -624,7 +630,8 @@ static int __devinit ds1307_probe(struct i2c_client *client, && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) return -EIO; - if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL))) + ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL); + if (!ds1307) return -ENOMEM; i2c_set_clientdata(client, ds1307); @@ -659,7 +666,8 @@ static int __devinit ds1307_probe(struct i2c_client *client, if (ds1307->regs[0] & DS1337_BIT_nEOSC) ds1307->regs[0] &= ~DS1337_BIT_nEOSC; - /* Using IRQ? Disable the square wave and both alarms. + /* + * Using IRQ? Disable the square wave and both alarms. * For some variants, be sure alarms can trigger when we're * running on Vbackup (BBSQI/BBSQW) */ @@ -765,7 +773,8 @@ read_rtc: goto exit_free; } - /* minimal sanity checking; some chips (like DS1340) don't + /* + * minimal sanity checking; some chips (like DS1340) don't * specify the extra bits as must-be-zero, but there are * still a few values that are clearly out-of-range. */ @@ -837,7 +846,8 @@ read_rtc: switch (ds1307->type) { case ds_1340: case m41t00: - /* NOTE: ignores century bits; fix before deploying + /* + * NOTE: ignores century bits; fix before deploying * systems that will run through year 2100. */ break; @@ -847,7 +857,8 @@ read_rtc: if (!(tmp & DS1307_BIT_12HR)) break; - /* Be sure we're in 24 hour mode. Multi-master systems + /* + * Be sure we're in 24 hour mode. Multi-master systems * take note... */ tmp = bcd2bin(tmp & 0x1f); @@ -902,7 +913,7 @@ exit_free: static int __devexit ds1307_remove(struct i2c_client *client) { - struct ds1307 *ds1307 = i2c_get_clientdata(client); + struct ds1307 *ds1307 = i2c_get_clientdata(client); if (test_and_clear_bit(HAS_ALARM, &ds1307->flags)) { free_irq(client->irq, client); |