[PATCH 1/2] leds: tps6131x: queue torch refresh work on freezable workqueue

[Jiale Yao]

The torch watchdog refresh work performs I2C register writes and
reschedules itself every ten seconds while the torch is enabled. Since
schedule_delayed_work() uses the non-freezable system workqueue, the
callback can run after the I2C adapter has been suspended.

Queue the refresh on system_freezable_wq so it is frozen before devices
are suspended and resumed only after they become available again.

Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
---
 drivers/leds/flash/leds-tps6131x.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/leds/flash/leds-tps6131x.c b/drivers/leds/flash/leds-tps6131x.c
index 5c9a5af5af05..841a6538e75e 100644
--- a/drivers/leds/flash/leds-tps6131x.c
+++ b/drivers/leds/flash/leds-tps6131x.c
@@ -11,6 +11,7 @@
 #include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/regmap.h>
+#include <linux/workqueue.h>
 #include <media/v4l2-flash-led-class.h>
 
 #define TPS6131X_REG_0				0x00
@@ -307,8 +308,9 @@ static void tps6131x_torch_refresh_handler(struct work_struct *work)
 		return;
 	}
 
-	schedule_delayed_work(&tps6131x->torch_refresh_work,
-			      TPS6131X_TORCH_REFRESH_INTERVAL_JIFFIES);
+	queue_delayed_work(system_freezable_wq,
+			   &tps6131x->torch_refresh_work,
+			   TPS6131X_TORCH_REFRESH_INTERVAL_JIFFIES);
 }
 
 static int tps6131x_brightness_set(struct led_classdev *cdev, enum led_brightness brightness)
@@ -367,8 +369,9 @@ static int tps6131x_brightness_set(struct led_classdev *cdev, enum led_brightnes
 	 * To prevent this, the mode must be refreshed within the watchdog timeout.
 	 */
 	if (brightness)
-		schedule_delayed_work(&tps6131x->torch_refresh_work,
-				      TPS6131X_TORCH_REFRESH_INTERVAL_JIFFIES);
+		queue_delayed_work(system_freezable_wq,
+				   &tps6131x->torch_refresh_work,
+				   TPS6131X_TORCH_REFRESH_INTERVAL_JIFFIES);
 
 	return 0;
 }
-- 
2.34.1