Re: [PATCH v4 4/5] HID: asus: add support for xgm led

[Antheas Kapenekakis]

On Mon, 15 Jun 2026 at 18:51, Denis Benato <denis.benato@xxxxxxxxx> wrote:
>
> XG mobile stations have very bright leds behind the fan that can be
> turned either ON or OFF: add a cled interface to allow controlling the
> brightness of those red leds.
>
> Signed-off-by: Denis Benato <denis.benato@xxxxxxxxx>
> ---
>  drivers/hid/hid-asus.c | 91 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 91 insertions(+)
>
> diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c
> index 6896730efafc..e68a6d93369d 100644
> --- a/drivers/hid/hid-asus.c
> +++ b/drivers/hid/hid-asus.c
> @@ -51,6 +51,8 @@ MODULE_DESCRIPTION("Asus HID Keyboard and TouchPad");
>  #define FEATURE_KBD_LED_REPORT_ID1 0x5d
>  #define FEATURE_KBD_LED_REPORT_ID2 0x5e
>
> +#define ROG_XGM_REPORT_SIZE 300
> +
>  #define ROG_ALLY_REPORT_SIZE 64
>  #define ROG_ALLY_X_MIN_MCU 313
>  #define ROG_ALLY_MIN_MCU 319
> @@ -143,6 +145,11 @@ struct asus_worker {
>         bool removed;
>  };
>
> +struct asus_xgm_led {
> +       struct led_classdev cdev;
> +       struct hid_device *hdev;
> +};
> +
>  struct asus_touchpad_info {
>         int max_x;
>         int max_y;
> @@ -169,6 +176,7 @@ struct asus_drvdata {
>         unsigned long battery_next_query;
>         struct asus_hid_listener listener;
>         bool fn_lock;
> +       struct asus_xgm_led *xgm_led;
>  };
>
>  static int asus_report_battery(struct asus_drvdata *, u8 *, int);
> @@ -1119,6 +1127,26 @@ static int asus_battery_probe(struct hid_device *hdev)
>         return ret;
>  }
>
> +static int asus_xgm_led_set(struct led_classdev *led_cdev, enum led_brightness value)
> +{
> +       const u8 buf[ROG_XGM_REPORT_SIZE] = {
> +               FEATURE_KBD_LED_REPORT_ID2, 0xC5, (value) ? 0x50 : 0x00
> +       };
> +       struct asus_xgm_led *xgm = container_of(led_cdev, struct asus_xgm_led, cdev);
> +       int ret;
> +
> +       ret = asus_kbd_set_report(xgm->hdev, buf, ROG_XGM_REPORT_SIZE);
> +       if (ret < 0) {
> +               hid_err(xgm->hdev, "Unable to set XG mobile led state: %d\n", ret);
> +               return ret;
> +       } else if (ret != ROG_XGM_REPORT_SIZE) {
> +               hid_err(xgm->hdev, "Unexpected partial transfer to XG mobile: %d\n", ret);
> +               return -EIO;
> +       }
> +
> +       return 0;
> +}
> +
>  static int asus_input_configured(struct hid_device *hdev, struct hid_input *hi)
>  {
>         struct input_dev *input = hi->input;
> @@ -1343,9 +1371,52 @@ static int asus_start_multitouch(struct hid_device *hdev)
>         return 0;
>  }
>
> +static int asus_xgm_init(struct hid_device *hdev, struct asus_drvdata *drvdata)
> +{
> +       const char *name;
> +       int ret;
> +
> +       drvdata->xgm_led = devm_kzalloc(&hdev->dev, sizeof(*drvdata->xgm_led), GFP_KERNEL);
> +       if (drvdata->xgm_led == NULL)
> +               return -ENOMEM;
> +
> +       name = devm_kasprintf(&hdev->dev, GFP_KERNEL, "asus:xgm-%s:led",
> +                             strlen(hdev->uniq) ? hdev->uniq : dev_name(&hdev->dev));
> +
> +       if (name == NULL) {
> +               ret = -ENOMEM;
> +               goto asus_xgm_init_err;
> +       }
> +
> +       drvdata->xgm_led->hdev = hdev;
> +       drvdata->xgm_led->cdev.name = name;
> +       drvdata->xgm_led->cdev.brightness = 1;
> +       drvdata->xgm_led->cdev.max_brightness = 1;
> +       drvdata->xgm_led->cdev.brightness_set_blocking = asus_xgm_led_set;
> +
> +       /* LED state is arbitrary on boot, set a default */
> +       ret = asus_xgm_led_set(&drvdata->xgm_led->cdev, drvdata->xgm_led->cdev.brightness);
> +       if (ret) {
> +               hid_err(hdev, "Asus failed to set xgm led: %d\n", ret);
> +               goto asus_xgm_init_err;
> +       }
> +
> +       ret = devm_led_classdev_register(&hdev->dev, &drvdata->xgm_led->cdev);
> +       if (ret) {
> +               hid_err(hdev, "Asus failed to register xgm led: %d\n", ret);
> +               goto asus_xgm_init_err;
> +       }
> +
> +       return 0;
> +asus_xgm_init_err:
> +       drvdata->xgm_led = NULL;
> +       return ret;
> +}
> +
>  static int __maybe_unused asus_resume(struct hid_device *hdev)
>  {
>         struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
> +       int ret;
>
>         /*
>          * If we have a backlight listener registered, restore the previous state,
> @@ -1355,7 +1426,17 @@ static int __maybe_unused asus_resume(struct hid_device *hdev)
>         if (drvdata->listener.brightness_set)
>                 asus_kbd_backlight_set(&drvdata->listener, drvdata->kbd_backlight_brightness);
>
> +       if (drvdata->xgm_led) {
> +               ret = asus_xgm_led_set(&drvdata->xgm_led->cdev, drvdata->xgm_led->cdev.brightness);
> +               if (ret) {
> +                       hid_err(hdev, "Asus failed to restore xgm brightness: %d\n", ret);
> +                       goto asus_resume_err;
> +               }
> +       }
> +
>         return 0;
> +asus_resume_err:
> +       return ret;
>  }
>
>  static int __maybe_unused asus_reset_resume(struct hid_device *hdev)
> @@ -1484,6 +1565,16 @@ static int asus_probe(struct hid_device *hdev, const struct hid_device_id *id)
>                 }
>         }
>
> +       if (asus_has_report_id(hdev, FEATURE_KBD_REPORT_ID) &&
> +           ((hdev->product == USB_DEVICE_ID_ASUSTEK_XGM_2022) ||
> +            (hdev->product == USB_DEVICE_ID_ASUSTEK_XGM_2023))) {
> +               ret = asus_xgm_init(hdev, drvdata);
> +               if (ret) {
> +                       hid_err(hdev, "Failed to initialize xg mobile: %d\n", ret);
> +                       goto err_stop_hw;
> +               }
> +       }
> +

reset_resume has a special meaning and perhaps should not have been
used for this driver at all. Check if resume works and if it does use
that instead.

Other than that and the refactor patch I'd rather see separately, the
other 4 patches look fine to me.

Reviewed-by: Antheas Kapenekakis <lkml@xxxxxxxxxxx>

Best,
Antheas

>         /* Laptops keyboard backlight is always at 0x5a */
>         if (is_vendor && (drvdata->quirks & QUIRK_USE_KBD_BACKLIGHT) &&
>             (asus_has_report_id(hdev, FEATURE_KBD_REPORT_ID)) &&
> --
> 2.47.3
>
>