Input: qt2160 - switch to using brightness_set_blocking()

Commit Message

Dmitry Torokhov Feb. 9, 2019, 5:20 p.m. UTC

Now that LEDs core allows "blocking" flavor of "set brightness" method we
can use it and get rid of private work items.

Signed-off-by: Dmitry Torokhov <[e-mail]>
---
 drivers/input/keyboard/qt2160.c | 69 +++++++++++++--------------------
 1 file changed, 27 insertions(+), 42 deletions(-)

Comments

Sven Van Asbroeck Feb. 10, 2019, 11:47 p.m. UTC | #1

On Sat, Feb 9, 2019 at 12:21 PM Dmitry Torokhov
<[e-mail]> wrote:
>
> Now that LEDs core allows "blocking" flavor of "set brightness" method we
> can use it and get rid of private work items.
>
> Signed-off-by: Dmitry Torokhov <[e-mail]>

Looking good !

Reviewed-by: Sven Van Asbroeck <[e-mail]>

Good job to get rid of that led_lock mutex. It didn't serve any purpose
but more importantly, it could introduce a sleep in brightness_set,
which cannot sleep...

Patch

diff --git a/drivers/input/keyboard/qt2160.c b/drivers/input/keyboard/qt2160.c
index 43b86482dda0..d466bc07aebb 100644
--- a/drivers/input/keyboard/qt2160.c
+++ b/drivers/input/keyboard/qt2160.c
@@ -58,10 +58,9 @@  static unsigned char qt2160_key2code[] = {
 struct qt2160_led {
 	struct qt2160_data *qt2160;
 	struct led_classdev cdev;
-	struct work_struct work;
 	char name[32];
 	int id;
-	enum led_brightness new_brightness;
+	enum led_brightness brightness;
 };
 #endif
 
@@ -74,7 +73,6 @@  struct qt2160_data {
 	u16 key_matrix;
 #ifdef CONFIG_LEDS_CLASS
 	struct qt2160_led leds[QT2160_NUM_LEDS_X];
-	struct mutex led_lock;
 #endif
 };
 
@@ -83,46 +81,39 @@  static int qt2160_write(struct i2c_client *client, u8 reg, u8 data);
 
 #ifdef CONFIG_LEDS_CLASS
 
-static void qt2160_led_work(struct work_struct *work)
+static int qt2160_led_set(struct led_classdev *cdev,
+			  enum led_brightness value)
 {
-	struct qt2160_led *led = container_of(work, struct qt2160_led, work);
+	struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
 	struct qt2160_data *qt2160 = led->qt2160;
 	struct i2c_client *client = qt2160->client;
-	int value = led->new_brightness;
 	u32 drive, pwmen;
 
-	mutex_lock(&qt2160->led_lock);
-
-	drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
-	pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
-	if (value != LED_OFF) {
-		drive |= (1 << led->id);
-		pwmen |= (1 << led->id);
-
-	} else {
-		drive &= ~(1 << led->id);
-		pwmen &= ~(1 << led->id);
-	}
-	qt2160_write(client, QT2160_CMD_DRIVE_X, drive);
-	qt2160_write(client, QT2160_CMD_PWMEN_X, pwmen);
+	if (value != led->brightness) {
+		drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
+		pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
+		if (value != LED_OFF) {
+			drive |= BIT(led->id);
+			pwmen |= BIT(led->id);
 
-	/*
-	 * Changing this register will change the brightness
-	 * of every LED in the qt2160. It's a HW limitation.
-	 */
-	if (value != LED_OFF)
-		qt2160_write(client, QT2160_CMD_PWM_DUTY, value);
+		} else {
+			drive &= ~BIT(led->id);
+			pwmen &= ~BIT(led->id);
+		}
+		qt2160_write(client, QT2160_CMD_DRIVE_X, drive);
+		qt2160_write(client, QT2160_CMD_PWMEN_X, pwmen);
 
-	mutex_unlock(&qt2160->led_lock);
-}
+		/*
+		 * Changing this register will change the brightness
+		 * of every LED in the qt2160. It's a HW limitation.
+		 */
+		if (value != LED_OFF)
+			qt2160_write(client, QT2160_CMD_PWM_DUTY, value);
 
-static void qt2160_led_set(struct led_classdev *cdev,
-			   enum led_brightness value)
-{
-	struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
+		led->brightness = value;
+	}
 
-	led->new_brightness = value;
-	schedule_work(&led->work);
+	return 0;
 }
 
 #endif /* CONFIG_LEDS_CLASS */
@@ -293,20 +284,16 @@  static int qt2160_register_leds(struct qt2160_data *qt2160)
 	int ret;
 	int i;
 
-	mutex_init(&qt2160->led_lock);
-
 	for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
 		struct qt2160_led *led = &qt2160->leds[i];
 
 		snprintf(led->name, sizeof(led->name), "qt2160:x%d", i);
 		led->cdev.name = led->name;
-		led->cdev.brightness_set = qt2160_led_set;
+		led->cdev.brightness_set_blocking = qt2160_led_set;
 		led->cdev.brightness = LED_OFF;
 		led->id = i;
 		led->qt2160 = qt2160;
 
-		INIT_WORK(&led->work, qt2160_led_work);
-
 		ret = led_classdev_register(&client->dev, &led->cdev);
 		if (ret < 0)
 			return ret;
@@ -324,10 +311,8 @@  static void qt2160_unregister_leds(struct qt2160_data *qt2160)
 {
 	int i;
 
-	for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
+	for (i = 0; i < QT2160_NUM_LEDS_X; i++)
 		led_classdev_unregister(&qt2160->leds[i].cdev);
-		cancel_work_sync(&qt2160->leds[i].work);
-	}
 }
 
 #else