rtc: ds1343: remove unnecessary mutex

Use rtc_lock and rtc_unlock to lock the rtc from the interrupt handler.
This removes the need for a driver specific lock.

Link: https://lore.kernel.org/r/20191019204941.6203-7-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/rtc/rtc-ds1343.c b/drivers/rtc/rtc-ds1343.c
index 42c785c..fc6d77f 100644 (file)
--- a/drivers/rtc/rtc-ds1343.c
+++ b/drivers/rtc/rtc-ds1343.c
@@ -78,7 +78,6 @@ struct ds1343_priv {
        struct spi_device *spi;
        struct rtc_device *rtc;
        struct regmap *map;
-       struct mutex mutex;
        unsigned int irqen;
        int irq;
        int alarm_sec;
@@ -290,17 +289,15 @@ static int ds1343_update_alarm(struct device *dev)
 static int ds1343_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
        struct ds1343_priv *priv = dev_get_drvdata(dev);
-       int res = 0;
+       int res;
        unsigned int stat;
 
        if (priv->irq <= 0)
                return -EINVAL;
 
-       mutex_lock(&priv->mutex);
-
        res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
        if (res)
-               goto out;
+               return res;
 
        alarm->enabled = !!(priv->irqen & RTC_AF);
        alarm->pending = !!(stat & DS1343_IRQF0);
@@ -310,21 +307,16 @@ static int ds1343_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
        alarm->time.tm_hour = priv->alarm_hour < 0 ? 0 : priv->alarm_hour;
        alarm->time.tm_mday = priv->alarm_mday < 0 ? 0 : priv->alarm_mday;
 
-out:
-       mutex_unlock(&priv->mutex);
-       return res;
+       return 0;
 }
 
 static int ds1343_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
        struct ds1343_priv *priv = dev_get_drvdata(dev);
-       int res = 0;
 
        if (priv->irq <= 0)
                return -EINVAL;
 
-       mutex_lock(&priv->mutex);
-
        priv->alarm_sec = alarm->time.tm_sec;
        priv->alarm_min = alarm->time.tm_min;
        priv->alarm_hour = alarm->time.tm_hour;
@@ -333,33 +325,22 @@ static int ds1343_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
        if (alarm->enabled)
                priv->irqen |= RTC_AF;
 
-       res = ds1343_update_alarm(dev);
-
-       mutex_unlock(&priv->mutex);
-
-       return res;
+       return ds1343_update_alarm(dev);
 }
 
 static int ds1343_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
        struct ds1343_priv *priv = dev_get_drvdata(dev);
-       int res = 0;
 
        if (priv->irq <= 0)
                return -EINVAL;
 
-       mutex_lock(&priv->mutex);
-
        if (enabled)
                priv->irqen |= RTC_AF;
        else
                priv->irqen &= ~RTC_AF;
 
-       res = ds1343_update_alarm(dev);
-
-       mutex_unlock(&priv->mutex);
-
-       return res;
+       return ds1343_update_alarm(dev);
 }
 
 static irqreturn_t ds1343_thread(int irq, void *dev_id)
@@ -368,7 +349,7 @@ static irqreturn_t ds1343_thread(int irq, void *dev_id)
        unsigned int stat, control;
        int res = 0;
 
-       mutex_lock(&priv->mutex);
+       rtc_lock(priv->rtc);
 
        res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
        if (res)
@@ -389,7 +370,7 @@ static irqreturn_t ds1343_thread(int irq, void *dev_id)
        }
 
 out:
-       mutex_unlock(&priv->mutex);
+       rtc_unlock(priv->rtc);
        return IRQ_HANDLED;
 }
 
@@ -422,7 +403,6 @@ static int ds1343_probe(struct spi_device *spi)
                return -ENOMEM;
 
        priv->spi = spi;
-       mutex_init(&priv->mutex);
 
        /* RTC DS1347 works in spi mode 3 and
         * its chip select is active high
@@ -500,9 +480,7 @@ static int ds1343_remove(struct spi_device *spi)
        struct ds1343_priv *priv = spi_get_drvdata(spi);
 
        if (spi->irq) {
-               mutex_lock(&priv->mutex);
                priv->irqen &= ~RTC_AF;
-               mutex_unlock(&priv->mutex);
 
                dev_pm_clear_wake_irq(&spi->dev);
                device_init_wakeup(&spi->dev, false);