[PATCH v2] platform/x86: asus-wmi: support the disable camera LED on F10 of Zenbook 2023

[Devin Bayer <dev@doubly.so>]

Adds a sysfs entry for the LED on F10 above the crossed out camera icon on 2023 Zenbooks.

v2
- Changed name from `platform::camera` to `asus::camera`
- Separated patch from patchset

v1
- https://lore.kernel.org/platform-driver-x86/20240620082223.20178-1-dev@doubly.so/

Signed-off-by: Devin Bayer <dev@doubly.so>
---
 drivers/platform/x86/asus-wmi.c            | 36 ++++++++++++++++++++++
 include/linux/platform_data/x86/asus-wmi.h |  2 ++
 2 files changed, 38 insertions(+)

diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 3f07bbf809ef..20b7ed6a27b5 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -73,6 +73,7 @@ module_param(fnlock_default, bool, 0444);
 #define NOTIFY_LID_FLIP_ROG		0xbd
 
 #define ASUS_WMI_FNLOCK_BIOS_DISABLED	BIT(0)
+#define ASUS_WMI_DEVID_CAMERA_LED		0x00060079
 
 #define ASUS_MID_FAN_DESC		"mid_fan"
 #define ASUS_GPU_FAN_DESC		"gpu_fan"
@@ -227,6 +228,7 @@ struct asus_wmi {
 	struct led_classdev lightbar_led;
 	int lightbar_led_wk;
 	struct led_classdev micmute_led;
+	struct led_classdev camera_led;
 	struct workqueue_struct *led_workqueue;
 	struct work_struct tpd_led_work;
 	struct work_struct wlan_led_work;
@@ -1533,6 +1535,27 @@ static int micmute_led_set(struct led_classdev *led_cdev,
 	return err < 0 ? err : 0;
 }
 
+static enum led_brightness camera_led_get(struct led_classdev *led_cdev)
+{
+	struct asus_wmi *asus;
+	u32 result;
+
+	asus = container_of(led_cdev, struct asus_wmi, camera_led);
+	asus_wmi_get_devstate(asus, ASUS_WMI_DEVID_CAMERA_LED, &result);
+
+	return result & ASUS_WMI_DSTS_BRIGHTNESS_MASK;
+}
+
+static int camera_led_set(struct led_classdev *led_cdev,
+			   enum led_brightness brightness)
+{
+	int state = brightness != LED_OFF;
+	int err;
+
+	err = asus_wmi_set_devstate(ASUS_WMI_DEVID_CAMERA_LED, state, NULL);
+	return err < 0 ? err : 0;
+}
+
 static void asus_wmi_led_exit(struct asus_wmi *asus)
 {
 	led_classdev_unregister(&asus->kbd_led);
@@ -1540,6 +1563,7 @@ static void asus_wmi_led_exit(struct asus_wmi *asus)
 	led_classdev_unregister(&asus->wlan_led);
 	led_classdev_unregister(&asus->lightbar_led);
 	led_classdev_unregister(&asus->micmute_led);
+	led_classdev_unregister(&asus->camera_led);
 
 	if (asus->led_workqueue)
 		destroy_workqueue(asus->led_workqueue);
@@ -1631,6 +1655,18 @@ static int asus_wmi_led_init(struct asus_wmi *asus)
 			goto error;
 	}
 
+	if (asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_CAMERA_LED)) {
+		asus->camera_led.name = "asus::camera";
+		asus->camera_led.max_brightness = 1;
+		asus->camera_led.brightness_get = camera_led_get;
+		asus->camera_led.brightness_set_blocking = camera_led_set;
+
+		rv = led_classdev_register(&asus->platform_device->dev,
+						&asus->camera_led);
+		if (rv)
+			goto error;
+	}
+
 error:
 	if (rv)
 		asus_wmi_led_exit(asus);
diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h
index ab1c7deff118..fb0b00f7d292 100644
--- a/include/linux/platform_data/x86/asus-wmi.h
+++ b/include/linux/platform_data/x86/asus-wmi.h
@@ -50,6 +50,8 @@
 #define ASUS_WMI_DEVID_LED5		0x00020015
 #define ASUS_WMI_DEVID_LED6		0x00020016
 #define ASUS_WMI_DEVID_MICMUTE_LED		0x00040017
+#define ASUS_WMI_DEVID_CAMERA_LED_NEG		0x00060078
+#define ASUS_WMI_DEVID_CAMERA_LED		0x00060079
 
 /* Backlight and Brightness */
 #define ASUS_WMI_DEVID_ALS_ENABLE	0x00050001 /* Ambient Light Sensor */
-- 
2.45.2