leds: core: Fix regression caused by commit 2b83ff9

jacek-anaszewski · jacek-anaszewski · commit 7b6af2c53192 · 2018-01-07T13:27:07.000+01:00
Commit 2b83ff9 ("led: core: Fix brightness setting when setting delay_off=0") replaced del_timer_sync(&led_cdev->blink_timer) with led_stop_software_blink() in led_blink_set(), which additionally clears LED_BLINK_SW flag as well as zeroes blink_delay_on and blink_delay_off properties of the struct led_classdev. Cleansing of the latter ones wasn't required to fix the original issue but wasn't considered harmful. It nonetheless turned out to be so in case when pointer to one or both props is passed to led_blink_set() like in the ledtrig-timer.c. In such cases zeroes are passed later in delay_on and/or delay_off arguments to led_blink_setup(), which results either in stopping the software blinking or setting blinking frequency always to 1Hz. Avoid using led_stop_software_blink() and add a single call required to clear LED_BLINK_SW flag, which was the only needed modification to fix the original issue. Fixes 2b83ff9 ("led: core: Fix brightness setting when setting delay_off=0") Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
@@ -186,8 +186,9 @@ void led_blink_set(struct led_classdev *led_cdev,
 		   unsigned long *delay_on,
 		   unsigned long *delay_off)
 {
-	led_stop_software_blink(led_cdev);
+	del_timer_sync(&led_cdev->blink_timer);
 
+	clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
 	clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
 	clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
 

Original file line number	Diff line number	Diff line change
`@@ -186,8 +186,9 @@ void led_blink_set(struct led_classdev *led_cdev,`
`186`	`186`	`unsigned long *delay_on,`
`187`	`187`	`unsigned long *delay_off)`
`188`	`188`	`{`
`189`		`- led_stop_software_blink(led_cdev);`
	`189`	`+ del_timer_sync(&led_cdev->blink_timer);`
`190`	`190`
	`191`	`+ clear_bit(LED_BLINK_SW, &led_cdev->work_flags);`
`191`	`192`	`clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);`
`192`	`193`	`clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);`
`193`	`194`