leds: convert blink timer to workqueue

This patch converts the blink timer from led-core to workqueue which is more
suitable for this kind of non-priority operations. Moreover, timer may lead to
errors when a LED setting function use a scheduling function such as pinctrl
which is using mutex.

Signed-off-by: Vincent Donnefort <vdonnefort@gmail.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

1 files changed, 6 insertions, 5 deletions

diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
index 71b40d3bf776..4bb116867b88 100644
--- a/drivers/leds/led-core.c
+++ b/drivers/leds/led-core.c
@@ -16,6 +16,7 @@
 #include <linux/module.h>
 #include <linux/rwsem.h>
 #include <linux/leds.h>
+#include <linux/workqueue.h>
 #include "leds.h"
 
 DECLARE_RWSEM(leds_list_lock);
@@ -51,7 +52,7 @@ static void led_set_software_blink(struct led_classdev *led_cdev,
                 return;
         }
 
-        mod_timer(&led_cdev->blink_timer, jiffies + 1);
+        queue_delayed_work(system_wq, &led_cdev->blink_work, 1);
 }
 
 
@@ -75,7 +76,7 @@ void led_blink_set(struct led_classdev *led_cdev,
                    unsigned long *delay_on,
                    unsigned long *delay_off)
 {
-        del_timer_sync(&led_cdev->blink_timer);
+        cancel_delayed_work_sync(&led_cdev->blink_work);
 
         led_cdev->flags &= ~LED_BLINK_ONESHOT;
         led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;
@@ -90,7 +91,7 @@ void led_blink_set_oneshot(struct led_classdev *led_cdev,
                            int invert)
 {
         if ((led_cdev->flags & LED_BLINK_ONESHOT) &&
-             timer_pending(&led_cdev->blink_timer))
+             delayed_work_pending(&led_cdev->blink_work))
                 return;
 
         led_cdev->flags |= LED_BLINK_ONESHOT;
@@ -107,7 +108,7 @@ EXPORT_SYMBOL(led_blink_set_oneshot);
 
 void led_stop_software_blink(struct led_classdev *led_cdev)
 {
-        del_timer_sync(&led_cdev->blink_timer);
+        cancel_delayed_work_sync(&led_cdev->blink_work);
         led_cdev->blink_delay_on = 0;
         led_cdev->blink_delay_off = 0;
 }
@@ -116,7 +117,7 @@ EXPORT_SYMBOL_GPL(led_stop_software_blink);
 void led_set_brightness(struct led_classdev *led_cdev,
                         enum led_brightness brightness)
 {
-        /* delay brightness setting if need to stop soft-blink timer */
+        /* delay brightness setting if need to stop soft-blink work */
         if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) {
                 led_cdev->delayed_set_value = brightness;
                 schedule_work(&led_cdev->set_brightness_work);