Hi, Sam:
Sam Ravnborg <sam@xxxxxxxxxxxx> 於 2022年7月18日 週一 凌晨1:45寫道：
>
> The mode_valid implementation had a call to
> drm_bridge_chain_mode_fixup() which would be wrong as the mode_valid is
> not allowed to change anything - only to validate the mode.
>
> As the next bridge is often/always a connector the call had no effect
> anyway. So drop it.
>
> From the git history I could see this call was included in the original
> version of the driver so there was no help there to find out why it was
> added in the first place. But a lot has changed since the initial driver
> were added and is seems safe to remove the call now.
Acked-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
>
> Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Reviewed-by: Maxime Ripard <mripard@xxxxxxxxxx>
> Cc: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
> Cc: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
> Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx>
> Cc: Dafna Hirschfeld <dafna.hirschfeld@xxxxxxxxxxxxx>
> Cc: linux-mediatek@xxxxxxxxxxxxxxxxxxx
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> ---
> drivers/gpu/drm/mediatek/mtk_hdmi.c | 11 -----------
> 1 file changed, 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> index 3196189429bc..a63b76055f81 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> @@ -1208,22 +1208,11 @@ static int mtk_hdmi_bridge_mode_valid(struct drm_bridge *bridge,
> const struct drm_display_mode *mode)
> {
> struct mtk_hdmi *hdmi = hdmi_ctx_from_bridge(bridge);
> - struct drm_bridge *next_bridge;
>
> dev_dbg(hdmi->dev, "xres=%d, yres=%d, refresh=%d, intl=%d clock=%d\n",
> mode->hdisplay, mode->vdisplay, drm_mode_vrefresh(mode),
> !!(mode->flags & DRM_MODE_FLAG_INTERLACE), mode->clock * 1000);
>
> - next_bridge = drm_bridge_get_next_bridge(&hdmi->bridge);
> - if (next_bridge) {
> - struct drm_display_mode adjusted_mode;
> -
> - drm_mode_copy(&adjusted_mode, mode);
> - if (!drm_bridge_chain_mode_fixup(next_bridge, mode,
> - &adjusted_mode))
> - return MODE_BAD;
> - }
> -
> if (hdmi->conf) {
> if (hdmi->conf->cea_modes_only && !drm_match_cea_mode(mode))
> return MODE_BAD;
> --
> 2.34.1
>
