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authorDavid Brownell <david-b@pacbell.net>2007-07-17 04:05:10 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-17 10:23:09 -0700
commitc065f35c17929067a367139d14e26897d60c7f6d (patch)
treee8c4c3c7bbf51e4b303a821f62c866a166f5e7f5 /drivers/rtc
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')
-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 5306a1a5b87..5158a625671 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -27,13 +27,8 @@
* This is currently a simple no-alarms driver. If your board has the
* alarm irq wired up on a ds1337 or ds1339, and you want to use that,
* then look at the rtc-rs5c372 driver for code to steal...
- *
- * If the I2C "force" mechanism is used, we assume the chip is a ds1337.
- * (Much better would be board-specific tables of I2C devices, along with
- * the platform_data drivers would use to sort such issues out.)
*/
enum ds_type {
- unknown = 0,
ds_1307,
ds_1337,
ds_1338,
@@ -43,11 +38,6 @@ enum ds_type {
// rs5c372 too? different address...
};
-static unsigned short normal_i2c[] = { 0x68, I2C_CLIENT_END };
-
-I2C_CLIENT_INSMOD;
-
-
/* RTC registers don't differ much, except for the century flag */
#define DS1307_REG_SECS 0x00 /* 00-59 */
@@ -55,6 +45,8 @@ I2C_CLIENT_INSMOD;
# define DS1340_BIT_nEOSC 0x80
#define DS1307_REG_MIN 0x01 /* 00-59 */
#define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
+# define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
+# define DS1307_BIT_PM 0x20 /* in REG_HOUR */
# define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
# define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
#define DS1307_REG_WDAY 0x03 /* 01-07 */
@@ -252,39 +244,27 @@ static const struct rtc_class_ops ds13xx_rtc_ops = {
static struct i2c_driver ds1307_driver;
-static int __devinit
-ds1307_detect(struct i2c_adapter *adapter, int address, int kind)
+static int __devinit ds1307_probe(struct i2c_client *client)
{
struct ds1307 *ds1307;
int err = -ENODEV;
- struct i2c_client *client;
int tmp;
const struct chip_desc *chip;
+ struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
- if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL))) {
- err = -ENOMEM;
- goto exit;
+ chip = find_chip(client->name);
+ if (!chip) {
+ dev_err(&client->dev, "unknown chip type '%s'\n",
+ client->name);
+ return -ENODEV;
}
- /* REVISIT: pending driver model conversion, set up "client"
- * ourselves, and use a hack to determine the RTC type (instead
- * of reading the client->name we're given)
- */
- client = &ds1307->dev;
- client->addr = address;
- client->adapter = adapter;
- client->driver = &ds1307_driver;
-
- /* HACK: "force" implies "needs ds1337-style-oscillator setup", and
- * that's the only kind of chip setup we'll know about. Until the
- * driver model conversion, here's where to add any board-specific
- * code to say what kind of chip is present...
- */
- if (kind >= 0)
- chip = find_chip("ds1337");
- else
- chip = find_chip("ds1307");
- strlcpy(client->name, chip->name, I2C_NAME_SIZE);
+ if (!i2c_check_functionality(adapter,
+ I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+ return -EIO;
+
+ if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL)))
+ return -ENOMEM;
ds1307->client = client;
i2c_set_clientdata(client, ds1307);
@@ -378,94 +358,92 @@ read_rtc:
goto read_rtc;
}
break;
- default:
+ case ds_1337:
+ case ds_1339:
break;
}
tmp = ds1307->regs[DS1307_REG_SECS];
tmp = BCD2BIN(tmp & 0x7f);
if (tmp > 60)
- goto exit_free;
+ goto exit_bad;
tmp = BCD2BIN(ds1307->regs[DS1307_REG_MIN] & 0x7f);
if (tmp > 60)
- goto exit_free;
+ goto exit_bad;
tmp = BCD2BIN(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
if (tmp == 0 || tmp > 31)
- goto exit_free;
+ goto exit_bad;
tmp = BCD2BIN(ds1307->regs[DS1307_REG_MONTH] & 0x1f);
if (tmp == 0 || tmp > 12)
- goto exit_free;
+ goto exit_bad;
- /* force into in 24 hour mode (most chips) or
- * disable century bit (ds1340)
- *
- * REVISIT forcing 24 hour mode can prevent multi-master
- * configs from sharing this RTC ... don't do this.
- * The clock needs to be reset after changing it, too...
- */
tmp = ds1307->regs[DS1307_REG_HOUR];
- if (tmp & (1 << 6)) {
- if (tmp & (1 << 5))
- tmp = BCD2BIN(tmp & 0x1f) + 12;
- else
- tmp = BCD2BIN(tmp);
+ switch (ds1307->type) {
+ case ds_1340:
+ case m41t00:
+ /* NOTE: ignores century bits; fix before deploying
+ * systems that will run through year 2100.
+ */
+ break;
+ default:
+ if (!(tmp & DS1307_BIT_12HR))
+ break;
+
+ /* Be sure we're in 24 hour mode. Multi-master systems
+ * take note...
+ */
+ tmp = BCD2BIN(tmp & 0x1f);
+ if (tmp == 12)
+ tmp = 0;
+ if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
+ tmp += 12;
i2c_smbus_write_byte_data(client,
DS1307_REG_HOUR,
BIN2BCD(tmp));
}
- /* Tell the I2C layer a new client has arrived */
- if ((err = i2c_attach_client(client)))
- goto exit_free;
-
ds1307->rtc = rtc_device_register(client->name, &client->dev,
&ds13xx_rtc_ops, THIS_MODULE);
if (IS_ERR(ds1307->rtc)) {
err = PTR_ERR(ds1307->rtc);
dev_err(&client->dev,
"unable to register the class device\n");
- goto exit_detach;
+ goto exit_free;
}
return 0;
-exit_detach:
- i2c_detach_client(client);
+exit_bad:
+ dev_dbg(&client->dev, "%s: %02x %02x %02x %02x %02x %02x %02x\n",
+ "bogus register",
+ ds1307->regs[0], ds1307->regs[1],
+ ds1307->regs[2], ds1307->regs[3],
+ ds1307->regs[4], ds1307->regs[5],
+ ds1307->regs[6]);
+
exit_free:
kfree(ds1307);
-exit:
return err;
}
-static int __devinit
-ds1307_attach_adapter(struct i2c_adapter *adapter)
-{
- if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
- return 0;
- return i2c_probe(adapter, &addr_data, ds1307_detect);
-}
-
-static int __devexit ds1307_detach_client(struct i2c_client *client)
+static int __devexit ds1307_remove(struct i2c_client *client)
{
- int err;
struct ds1307 *ds1307 = i2c_get_clientdata(client);
rtc_device_unregister(ds1307->rtc);
- if ((err = i2c_detach_client(client)))
- return err;
kfree(ds1307);
return 0;
}
static struct i2c_driver ds1307_driver = {
.driver = {
- .name = "ds1307",
+ .name = "rtc-ds1307",
.owner = THIS_MODULE,
},
- .attach_adapter = ds1307_attach_adapter,
- .detach_client = __devexit_p(ds1307_detach_client),
+ .probe = ds1307_probe,
+ .remove = __devexit_p(ds1307_remove),
};
static int __init ds1307_init(void)