rtc: rx8025: protect ctrl1 register update by rtc->ops_lock

The ctrl1 register is accessed by alarm operations.  But it is updated
in threaded interrupt handler without acquiring rtc->ops_lock.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

diff --git a/drivers/rtc/rtc-rx8025.c b/drivers/rtc/rtc-rx8025.c
index 18240f526adede006710f01b4a335296411cc34a..259995281e0df910a6bac4438fe5696a99a07bea 100644 (file)
--- a/drivers/rtc/rtc-rx8025.c
+++ b/drivers/rtc/rtc-rx8025.c
@@ -146,8 +146,10 @@ static irqreturn_t rx8025_handle_irq(int irq, void *dev_id)
 {
        struct i2c_client *client = dev_id;
        struct rx8025_data *rx8025 = i2c_get_clientdata(client);
+       struct mutex *lock = &rx8025->rtc->ops_lock;
        int status;
 
+       mutex_lock(lock);
        status = rx8025_read_reg(client, RX8025_REG_CTRL2);
        if (status < 0)
                goto out;
@@ -172,6 +174,8 @@ static irqreturn_t rx8025_handle_irq(int irq, void *dev_id)
        }
 
 out:
+       mutex_unlock(lock);
+
        return IRQ_HANDLED;
 }