On Fri, Sep 12, 2025 at 04:58:44PM +0800, Damon Ding wrote:
> The &drm_panel_funcs.enable() and &drm_panel_funcs.disable() mainly
> help turn on/off the backlight to make the image visible, and the
> backlight operations are even needless if drm_panel_of_backlight() or
> drm_panel_dp_aux_backlight() is applied, in which case the enabling
> and disabling process just add necessary delays.
Not necessary, it can actually be turning the panel off and on. Maybe
it's worth squashing this patch into the panel_bridge conversion as it
will point out that these functions are still being called at a correct
times by the DRM bridge framework.
>
> Therefore, it should make sense to remove panel disabling and move
> panel enabling after analogix_dp_set_bridge() finished.
>
> Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
> ---
> drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 66d0cca1f268..c98058e9c917 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -749,9 +749,6 @@ static int analogix_dp_commit(struct analogix_dp_device *dp)
> {
> int ret;
>
> - /* Keep the panel disabled while we configure video */
> - drm_panel_disable(dp->plat_data->panel);
> -
> ret = analogix_dp_train_link(dp);
> if (ret) {
> dev_err(dp->dev, "unable to do link train, ret=%d\n", ret);
> @@ -771,9 +768,6 @@ static int analogix_dp_commit(struct analogix_dp_device *dp)
> return ret;
> }
>
> - /* Safe to enable the panel now */
> - drm_panel_enable(dp->plat_data->panel);
> -
> /* Check whether panel supports fast training */
> ret = analogix_dp_fast_link_train_detection(dp);
> if (ret)
> @@ -1156,6 +1150,7 @@ static void analogix_dp_bridge_atomic_enable(struct drm_bridge *bridge,
> while (timeout_loop < MAX_PLL_LOCK_LOOP) {
> if (analogix_dp_set_bridge(dp) == 0) {
> dp->dpms_mode = DRM_MODE_DPMS_ON;
> + drm_panel_enable(dp->plat_data->panel);
> return;
> }
> dev_err(dp->dev, "failed to set bridge, retry: %d\n",
> --
> 2.34.1
>
--
With best wishes
Dmitry