HID: playstation: expose DualSense player LEDs through LED class.

The DualSense player LEDs were so far not adjustable from user-space.
This patch exposes each LED individually through the LED class. Each
LED uses the new 'player' function resulting in a name like:
'inputX:white:player-1' for the first LED.

Signed-off-by: Roderick Colenbrander <roderick.colenbrander@sony.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Author: Roderick Colenbrander

drivers/hid/hid-playstation.c

@@ -56,6 +56,13 @@ struct ps_calibration_data {
 	int sens_denom;
 };
 
+struct ps_led_info {
+	const char *name;
+	const char *color;
+	enum led_brightness (*brightness_get)(struct led_classdev *cdev);
+	int (*brightness_set)(struct led_classdev *cdev, enum led_brightness);
+};
+
 /* Seed values for DualShock4 / DualSense CRC32 for different report types. */
 #define PS_INPUT_CRC32_SEED	0xA1
 #define PS_OUTPUT_CRC32_SEED	0xA2
@@ -531,6 +538,32 @@ static int ps_get_report(struct hid_device *hdev, uint8_t report_id, uint8_t *bu
 	return 0;
 }
 
+static int ps_led_register(struct ps_device *ps_dev, struct led_classdev *led,
+		const struct ps_led_info *led_info)
+{
+	int ret;
+
+	led->name = devm_kasprintf(&ps_dev->hdev->dev, GFP_KERNEL,
+			"%s:%s:%s", ps_dev->input_dev_name, led_info->color, led_info->name);
+
+	if (!led->name)
+		return -ENOMEM;
+
+	led->brightness = 0;
+	led->max_brightness = 1;
+	led->flags = LED_CORE_SUSPENDRESUME;
+	led->brightness_get = led_info->brightness_get;
+	led->brightness_set_blocking = led_info->brightness_set;
+
+	ret = devm_led_classdev_register(&ps_dev->hdev->dev, led);
+	if (ret) {
+		hid_err(ps_dev->hdev, "Failed to register LED %s: %d\n", led_info->name, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
 /* Register a DualSense/DualShock4 RGB lightbar represented by a multicolor LED. */
 static int ps_lightbar_register(struct ps_device *ps_dev, struct led_classdev_mc *lightbar_mc_dev,
 	int (*brightness_set)(struct led_classdev *, enum led_brightness))
@@ -822,6 +855,35 @@ static int dualsense_lightbar_set_brightness(struct led_classdev *cdev,
 	return 0;
 }
 
+static enum led_brightness dualsense_player_led_get_brightness(struct led_classdev *led)
+{
+	struct hid_device *hdev = to_hid_device(led->dev->parent);
+	struct dualsense *ds = hid_get_drvdata(hdev);
+
+	return !!(ds->player_leds_state & BIT(led - ds->player_leds));
+}
+
+static int dualsense_player_led_set_brightness(struct led_classdev *led, enum led_brightness value)
+{
+	struct hid_device *hdev = to_hid_device(led->dev->parent);
+	struct dualsense *ds = hid_get_drvdata(hdev);
+	unsigned long flags;
+	unsigned int led_index;
+
+	spin_lock_irqsave(&ds->base.lock, flags);
+
+	led_index = led - ds->player_leds;
+	if (value == LED_OFF)
+		ds->player_leds_state &= ~BIT(led_index);
+	else
+		ds->player_leds_state |= BIT(led_index);
+
+	ds->update_player_leds = true;
+	spin_unlock_irqrestore(&ds->base.lock, flags);
+
+	schedule_work(&ds->output_worker);
+}
+
 static void dualsense_init_output_report(struct dualsense *ds, struct dualsense_output_report *rp,
 		void *buf)
 {
@@ -1207,7 +1269,20 @@ static struct ps_device *dualsense_create(struct hid_device *hdev)
 	struct dualsense *ds;
 	struct ps_device *ps_dev;
 	uint8_t max_output_report_size;
-	int ret;
+	int i, ret;
+
+	static const struct ps_led_info player_leds_info[] = {
+		{ LED_FUNCTION_PLAYER1, "white", dualsense_player_led_get_brightness,
+				dualsense_player_led_set_brightness },
+		{ LED_FUNCTION_PLAYER2, "white", dualsense_player_led_get_brightness,
+				dualsense_player_led_set_brightness },
+		{ LED_FUNCTION_PLAYER3, "white", dualsense_player_led_get_brightness,
+				dualsense_player_led_set_brightness },
+		{ LED_FUNCTION_PLAYER4, "white", dualsense_player_led_get_brightness,
+				dualsense_player_led_set_brightness },
+		{ LED_FUNCTION_PLAYER5, "white", dualsense_player_led_get_brightness,
+				dualsense_player_led_set_brightness }
+	};
 
 	ds = devm_kzalloc(&hdev->dev, sizeof(*ds), GFP_KERNEL);
 	if (!ds)
@@ -1297,6 +1372,14 @@ static struct ps_device *dualsense_create(struct hid_device *hdev)
 	/* Set default lightbar color. */
 	dualsense_set_lightbar(ds, 0, 0, 128); /* blue */
 
+	for (i = 0; i < ARRAY_SIZE(player_leds_info); i++) {
+		const struct ps_led_info *led_info = &player_leds_info[i];
+
+		ret = ps_led_register(ps_dev, &ds->player_leds[i], led_info);
+		if (ret < 0)
+			goto err;
+	}
+
 	ret = ps_device_set_player_id(ps_dev);
 	if (ret) {
 		hid_err(hdev, "Failed to assign player id for DualSense: %d\n", ret);