Re: [PATCH v3 2/3] drm: Add bus flag for Sharp-specific signals

From: Sam Ravnborg
Date: Sat Apr 27 2019 - 02:32:22 EST


Hi Paul

On Fri, Apr 26, 2019 at 01:18:53AM +0200, Paul Cercueil wrote:
> Add the DRM_BUS_FLAG_SHARP_SIGNALS to the drm_bus_flags enum.
>
> This flags can be used when the display must be driven with the
> Sharp-specific signals SPL, CLS, REV, PS.
>
> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> ---
>
> Notes:
> v3: New patch
>
> include/drm/drm_connector.h | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index 02a131202add..ac7d58fd1e03 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -323,6 +323,8 @@ enum drm_panel_orientation {
> * edge of the pixel clock
> * @DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE: Sync signals are sampled on the falling
> * edge of the pixel clock
> + * @DRM_BUS_FLAG_SHARP_SIGNALS: Set if the Sharp-specific signals
> + * (SPL, CLS, PS, REV) must be used
> */
> enum drm_bus_flags {
> DRM_BUS_FLAG_DE_LOW = BIT(0),
> @@ -341,6 +343,7 @@ enum drm_bus_flags {
> DRM_BUS_FLAG_SYNC_DRIVE_NEGEDGE = DRM_BUS_FLAG_SYNC_NEGEDGE,
> DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE = DRM_BUS_FLAG_SYNC_NEGEDGE,
> DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE = DRM_BUS_FLAG_SYNC_POSEDGE,
> + DRM_BUS_FLAG_SHARP_SIGNALS = BIT(8),
> };

This solutions looks very good to me.
Now the panel can report to the display driver that is needs the
DRM_BUS_FLAG_SHARP_SIGNALS, so the display driver can adapt to the
connected display.
Obviously not many display drivers will support DRM_BUS_FLAG_SHARP_SIGNALS
but the one that does now no longer need to include panel configuration.

You can add:
Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx>

But we need Thierry or someone else with more knowledge in this
area to comment on this before we can apply it.
drm_bus_flag is today only timing related config, and there be a better
way to do this.

Thierry?

Sam