Re: [PATCH 1/7] drm/bridge: analogix_dp: drop extra calls to analogix_dp_prepare_panel()

Damon Ding
2025-04-14T02:35:35Z

Hi Dmitry,

On 2025/4/1 13:11, Dmitry Baryshkov wrote:
> The analogix_dp_prepare_panel() returns immediately if there is no
> attached panel. Drop several calls to this function which are performed
> when dp->plat_data->panel is NULL.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
> ---
> drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 22 +---------------------
> 1 file changed, 1 insertion(+), 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 042154e2d8ccd74ac2dc27fe527e810a50e08a09..ab1cfc340aa95bbf13fe021bd33227b565a5458d 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -1005,17 +1005,11 @@ static int analogix_dp_get_modes(struct drm_connector *connector)
> {
> struct analogix_dp_device *dp = to_dp(connector);
> const struct drm_edid *drm_edid;
> - int ret, num_modes = 0;
> + int num_modes = 0;
>
> if (dp->plat_data->panel) {
> num_modes += drm_panel_get_modes(dp->plat_data->panel, connector);
> } else {
> - ret = analogix_dp_prepare_panel(dp, true, false);
> - if (ret) {
> - DRM_ERROR("Failed to prepare panel (%d)\n", ret);
> - return 0;
> - }
> -
> drm_edid = drm_edid_read_ddc(connector, &dp->aux.ddc);
>
> drm_edid_connector_update(&dp->connector, drm_edid);
> @@ -1024,10 +1018,6 @@ static int analogix_dp_get_modes(struct drm_connector *connector)
> num_modes += drm_edid_connector_add_modes(&dp->connector);
> drm_edid_free(drm_edid);
> }
> -
> - ret = analogix_dp_prepare_panel(dp, false, false);
> - if (ret)
> - DRM_ERROR("Failed to unprepare panel (%d)\n", ret);
> }
>
> if (dp->plat_data->get_modes)
> @@ -1087,19 +1077,9 @@ analogix_dp_detect(struct drm_connector *connector, bool force)
> if (dp->plat_data->panel)
> return connector_status_connected;
>
> - ret = analogix_dp_prepare_panel(dp, true, false);
> - if (ret) {
> - DRM_ERROR("Failed to prepare panel (%d)\n", ret);
> - return connector_status_disconnected;
> - }
> -
> if (!analogix_dp_detect_hpd(dp))
> status = connector_status_connected;
>
> - ret = analogix_dp_prepare_panel(dp, false, false);
> - if (ret)
> - DRM_ERROR("Failed to unprepare panel (%d)\n", ret);
> -
> return status;
> }
>
>

With the patch series:
https://patchwork.kernel.org/project/linux-rockchip/list/?series=942183

When I verify this patch, there will be a small warning:
drivers/gpu/drm/bridge/analogix/analogix_dp_core.c:1075:6: warning:
unused variable 'ret' [-Wunused-variable]
int ret;
^

It should be better to remove the unused 'ret'.

Best regards,
Damon