On Tue, Sep 29, 2026 at 12:25:32PM +0800, Yongxing Mou wrote:
> From: Abhinav Kumar <[email protected]>
>
> Whenever virtual channel slot allocation changes, the DP
> source must send the action control trigger sequence to notify
> the sink about the same. This would be applicable during the
> start and stop of the pixel stream. Add the infrastructure
> to be able to send ACT packets for the DP controller when
> operating in MST mode.
>
> Add REG_DP_MST_ACT, the ACT trigger register used by this sequence.
>
> Signed-off-by: Abhinav Kumar <[email protected]>
> Signed-off-by: Yongxing Mou <[email protected]>
> ---
> drivers/gpu/drm/msm/dp/dp_ctrl.c | 44
> ++++++++++++++++++++++++++++++++++++-
> drivers/gpu/drm/msm/dp/dp_ctrl.h | 5 ++++-
> drivers/gpu/drm/msm/dp/dp_display.c | 3 ++-
> drivers/gpu/drm/msm/dp/dp_display.h | 1 +
> drivers/gpu/drm/msm/dp/dp_reg.h | 1 +
> 5 files changed, 51 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> index e1614bc49a7c..65d22505c2b6 100644
> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> @@ -142,6 +142,7 @@ struct msm_dp_ctrl_private {
> bool core_clks_on;
> bool link_clks_on;
> bool stream_clks_on[DP_STREAM_MAX];
> + bool mst_active;
I really don't like the idea of having this flag in two locations. Here
and in the msm_dp_display_private. Can we have it in one place only?
> };
>
[...]
>
> static void msm_dp_display_unprepare(struct msm_dp_display_private *dp)
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.h
> b/drivers/gpu/drm/msm/dp/dp_display.h
> index 83117e7619f3..472429d09200 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.h
> +++ b/drivers/gpu/drm/msm/dp/dp_display.h
> @@ -19,6 +19,7 @@ struct msm_dp {
> struct drm_bridge *bridge;
> bool audio_enabled;
> bool power_on;
> + bool mst_active;
> unsigned int connector_type;
> bool is_edp;
>
--
With best wishes
Dmitry
