watchdog: sch56xx: Remove unnecessary checks for register changes

Since the watchdog core keeps track of the watchdog's active state, start/stop
will never get called when no changes are necessary. So we can remove the
check for the output_enable register changing before writing it (which is
an expensive operation).

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Hans de Goede 2012-05-22 11:40:25 +02:00 committed by Wim Van Sebroeck
parent fb551405c0
commit 85a2e40cb5

View File

@ -334,18 +334,14 @@ static int watchdog_start(struct watchdog_device *wddev)
if (ret)
goto leave;
/* 2. Enable output (if not already enabled) */
if (!(data->watchdog_output_enable & SCH56XX_WDOG_OUTPUT_ENABLE)) {
val = data->watchdog_output_enable |
SCH56XX_WDOG_OUTPUT_ENABLE;
ret = sch56xx_write_virtual_reg(data->addr,
SCH56XX_REG_WDOG_OUTPUT_ENABLE,
val);
if (ret)
goto leave;
/* 2. Enable output */
val = data->watchdog_output_enable | SCH56XX_WDOG_OUTPUT_ENABLE;
ret = sch56xx_write_virtual_reg(data->addr,
SCH56XX_REG_WDOG_OUTPUT_ENABLE, val);
if (ret)
goto leave;
data->watchdog_output_enable = val;
}
data->watchdog_output_enable = val;
/* 3. Clear the watchdog event bit if set */
val = inb(data->addr + 9);
@ -377,21 +373,16 @@ static int watchdog_stop(struct watchdog_device *wddev)
int ret = 0;
u8 val;
if (data->watchdog_output_enable & SCH56XX_WDOG_OUTPUT_ENABLE) {
val = data->watchdog_output_enable &
~SCH56XX_WDOG_OUTPUT_ENABLE;
mutex_lock(data->io_lock);
ret = sch56xx_write_virtual_reg(data->addr,
SCH56XX_REG_WDOG_OUTPUT_ENABLE,
val);
mutex_unlock(data->io_lock);
if (ret)
return ret;
val = data->watchdog_output_enable & ~SCH56XX_WDOG_OUTPUT_ENABLE;
mutex_lock(data->io_lock);
ret = sch56xx_write_virtual_reg(data->addr,
SCH56XX_REG_WDOG_OUTPUT_ENABLE, val);
mutex_unlock(data->io_lock);
if (ret)
return ret;
data->watchdog_output_enable = val;
}
return ret;
data->watchdog_output_enable = val;
return 0;
}
static const struct watchdog_ops watchdog_ops = {