Re: [PATCH v6 03/10] drm/msm/dp: Read DPCD and sink count in bridge detect()

[Konrad Dybcio]

On 5/24/26 12:33 PM, Dmitry Baryshkov wrote:
> From: Jessica Zhang <jessica.zhang@xxxxxxxxxxxxxxxx>
> 
> Instead of relying on the link_ready flag to specify if DP is connected,
> read the DPCD bits and get the sink count to accurately detect if DP is
> connected.
> 
> Signed-off-by: Jessica Zhang <jessica.zhang@xxxxxxxxxxxxxxxx>
> Tested-by: Val Packett <val@xxxxxxxxxxxx> # x1e80100-dell-latitude-7455
> Tested-by: Yongxing Mou <yongxing.mou@xxxxxxxxxxxxxxxx> # Hamoa IOT EVK, QCS8300 Ride
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/msm/dp/dp_display.c | 63 +++++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/msm/dp/dp_drm.c     | 20 ------------
>  drivers/gpu/drm/msm/dp/dp_drm.h     |  2 ++
>  3 files changed, 65 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index 1dd168acbbc3..97c4752005c0 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -1152,6 +1152,69 @@ static int msm_dp_hpd_event_thread_start(struct msm_dp_display_private *msm_dp_p
>  	return 0;
>  }
>  
> +/**
> + * msm_dp_bridge_detect - callback to determine if connector is connected
> + *
> + * @bridge: Pointer to drm bridge structure
> + * @connector: Pointer to drm connector structure
> + *
> + * Returns: where there is a display connected to the DPTX (returning

		whether?

Otherwise, if keeping msm_dp_aux_enable_xfers(true) is intentional
in bailout cases:

Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>

Konrad