led: core: Use atomic bit-field for the blink-flags
All the LED_BLINK* flags are accessed read-modify-write from e.g.
led_set_brightness and led_blink_set_oneshot while both
set_brightness_work and the blink_timer may be running.
If these race then the modify step done by one of them may be lost,
switch the LED_BLINK* flags to a new atomic work_flags bit-field
to avoid this race.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
diff --git a/include/linux/leds.h b/include/linux/leds.h
index ddfcb2d..21c598b 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -42,16 +42,20 @@
#define LED_UNREGISTERING (1 << 1)
/* Upper 16 bits reflect control information */
#define LED_CORE_SUSPENDRESUME (1 << 16)
-#define LED_BLINK_SW (1 << 17)
-#define LED_BLINK_ONESHOT (1 << 18)
-#define LED_BLINK_ONESHOT_STOP (1 << 19)
-#define LED_BLINK_INVERT (1 << 20)
-#define LED_BLINK_BRIGHTNESS_CHANGE (1 << 21)
-#define LED_BLINK_DISABLE (1 << 22)
-#define LED_SYSFS_DISABLE (1 << 23)
-#define LED_DEV_CAP_FLASH (1 << 24)
-#define LED_HW_PLUGGABLE (1 << 25)
-#define LED_PANIC_INDICATOR (1 << 26)
+#define LED_SYSFS_DISABLE (1 << 17)
+#define LED_DEV_CAP_FLASH (1 << 18)
+#define LED_HW_PLUGGABLE (1 << 19)
+#define LED_PANIC_INDICATOR (1 << 20)
+
+ /* set_brightness_work / blink_timer flags, atomic, private. */
+ unsigned long work_flags;
+
+#define LED_BLINK_SW 0
+#define LED_BLINK_ONESHOT 1
+#define LED_BLINK_ONESHOT_STOP 2
+#define LED_BLINK_INVERT 3
+#define LED_BLINK_BRIGHTNESS_CHANGE 4
+#define LED_BLINK_DISABLE 5
/* Set LED brightness level
* Must not sleep. Use brightness_set_blocking for drivers