rtc: ds3232: use rtc->ops_lock to protect alarm operations
ds3232->mutex is used to protect for alarm operations which
need to access status and control registers.
But we can use rtc->ops_lock instead. rtc->ops_lock is held when most
of rtc_class_ops methods are called, so we only need to explicitly
acquire it from irq handler in order to protect form concurrent
accesses.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c
index 9857287..7edc889 100644
--- a/drivers/rtc/rtc-ds3232.c
+++ b/drivers/rtc/rtc-ds3232.c
@@ -52,11 +52,6 @@
int irq;
struct rtc_device *rtc;
- /* The mutex protects alarm operations, and prevents a race
- * between the enable_irq() in the workqueue and the free_irq()
- * in the remove function.
- */
- struct mutex mutex;
bool suspended;
};
@@ -187,8 +182,6 @@
int ret;
u8 buf[4];
- mutex_lock(&ds3232->mutex);
-
ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
if (ret)
goto out;
@@ -215,7 +208,6 @@
ret = 0;
out:
- mutex_unlock(&ds3232->mutex);
return ret;
}
@@ -233,8 +225,6 @@
if (ds3232->irq <= 0)
return -EINVAL;
- mutex_lock(&ds3232->mutex);
-
buf[0] = bin2bcd(alarm->time.tm_sec);
buf[1] = bin2bcd(alarm->time.tm_min);
buf[2] = bin2bcd(alarm->time.tm_hour);
@@ -267,7 +257,6 @@
ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
}
out:
- mutex_unlock(&ds3232->mutex);
return ret;
}
@@ -277,11 +266,9 @@
int control;
int ret;
- mutex_lock(&ds3232->mutex);
-
ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
if (ret)
- goto unlock;
+ return ret;
if (enabled)
/* enable alarm1 interrupt */
@@ -291,9 +278,6 @@
control &= ~(DS3232_REG_CR_A1IE);
ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
-unlock:
- mutex_unlock(&ds3232->mutex);
-
return ret;
}
@@ -311,10 +295,11 @@
{
struct device *dev = dev_id;
struct ds3232 *ds3232 = dev_get_drvdata(dev);
+ struct mutex *lock = &ds3232->rtc->ops_lock;
int ret;
int stat, control;
- mutex_lock(&ds3232->mutex);
+ mutex_lock(lock);
ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
if (ret)
@@ -352,7 +337,7 @@
}
unlock:
- mutex_unlock(&ds3232->mutex);
+ mutex_unlock(lock);
return IRQ_HANDLED;
}
@@ -380,8 +365,6 @@
ds3232->dev = dev;
dev_set_drvdata(dev, ds3232);
- mutex_init(&ds3232->mutex);
-
ret = ds3232_check_rtc_status(dev);
if (ret)
return ret;