[PATCH] watchdog: mena21_wdt: Drop unnecessary mutex lock

[Jia-Ju Bai]

There is already a mutex in the watchdog core which serializes
calls to the various API functions. 
So the mutex lock "drv->lock" is unnecessary and can be dropped.

Signed-off-by: Jia-Ju Bai <baijiaju1...@gmail.com>
---
 drivers/watchdog/mena21_wdt.c | 18 ------------------
 1 file changed, 18 deletions(-)

diff --git a/drivers/watchdog/mena21_wdt.c b/drivers/watchdog/mena21_wdt.c
index 25d5d2b8cfbe..0be7f50e8ff9 100644
--- a/drivers/watchdog/mena21_wdt.c
+++ b/drivers/watchdog/mena21_wdt.c
@@ -31,7 +31,6 @@ enum a21_wdt_gpios {
 
 struct a21_wdt_drv {
        struct watchdog_device wdt;
-       struct mutex lock;
        unsigned gpios[NUM_GPIOS];
 };
 
@@ -55,12 +54,8 @@ static int a21_wdt_start(struct watchdog_device *wdt)
 {
        struct a21_wdt_drv *drv = watchdog_get_drvdata(wdt);
 
-       mutex_lock(&drv->lock);
-
        gpio_set_value(drv->gpios[GPIO_WD_ENAB], 1);
 
-       mutex_unlock(&drv->lock);
-
        return 0;
 }
 
@@ -68,12 +63,8 @@ static int a21_wdt_stop(struct watchdog_device *wdt)
 {
        struct a21_wdt_drv *drv = watchdog_get_drvdata(wdt);
 
-       mutex_lock(&drv->lock);
-
        gpio_set_value(drv->gpios[GPIO_WD_ENAB], 0);
 
-       mutex_unlock(&drv->lock);
-
        return 0;
 }
 
@@ -81,14 +72,10 @@ static int a21_wdt_ping(struct watchdog_device *wdt)
 {
        struct a21_wdt_drv *drv = watchdog_get_drvdata(wdt);
 
-       mutex_lock(&drv->lock);
-
        gpio_set_value(drv->gpios[GPIO_WD_TRIG], 0);
        ndelay(10);
        gpio_set_value(drv->gpios[GPIO_WD_TRIG], 1);
 
-       mutex_unlock(&drv->lock);
-
        return 0;
 }
 
@@ -108,8 +95,6 @@ static int a21_wdt_set_timeout(struct watchdog_device *wdt,
                return -EINVAL;
        }
 
-       mutex_lock(&drv->lock);
-
        if (timeout == 1)
                gpio_set_value(drv->gpios[GPIO_WD_FAST], 1);
        else
@@ -117,8 +102,6 @@ static int a21_wdt_set_timeout(struct watchdog_device *wdt,
 
        wdt->timeout = timeout;
 
-       mutex_unlock(&drv->lock);
-
        return 0;
 }
 
@@ -191,7 +174,6 @@ static int a21_wdt_probe(struct platform_device *pdev)
                        return ret;
        }
 
-       mutex_init(&drv->lock);
        watchdog_init_timeout(&a21_wdt, 30, &pdev->dev);
        watchdog_set_nowayout(&a21_wdt, nowayout);
        watchdog_set_drvdata(&a21_wdt, drv);
-- 
2.17.0