On Mon, Aug 25, 2025 at 10:15:59PM +0800, Yongxing Mou wrote:
> From: Abhinav Kumar <quic_abhin...@quicinc.com>
>
> With MST, each DP controller can handle multiple streams.
> There shall be one dp_panel for each stream but the dp_display
> object shall be shared among them. To represent this abstraction,
> create a stream_id for each DP panel which shall be set by the
> MST stream. For SST, default this to stream 0.
>
> Use the stream ID to control the pixel clock of that respective
> stream by extending the clock handles and state tracking of the
> DP pixel clock to an array of max supported streams. The maximum
> streams currently is 4.
>
> Signed-off-by: Abhinav Kumar <quic_abhin...@quicinc.com>
> Signed-off-by: Yongxing Mou <yongxing....@oss.qualcomm.com>
> ---
> drivers/gpu/drm/msm/dp/dp_ctrl.c | 58
> ++++++++++++++++++++++---------------
> drivers/gpu/drm/msm/dp/dp_ctrl.h | 3 +-
> drivers/gpu/drm/msm/dp/dp_display.c | 27 +++++++++++++++--
> drivers/gpu/drm/msm/dp/dp_display.h | 2 ++
> drivers/gpu/drm/msm/dp/dp_panel.h | 11 +++++++
> 5 files changed, 73 insertions(+), 28 deletions(-)
> @@ -2677,10 +2675,11 @@ static const char *ctrl_clks[] = {
> "ctrl_link_iface",
> };
>
> -static int msm_dp_ctrl_clk_init(struct msm_dp_ctrl *msm_dp_ctrl)
> +static int msm_dp_ctrl_clk_init(struct msm_dp_ctrl *msm_dp_ctrl, int
> max_stream)
> {
> struct msm_dp_ctrl_private *ctrl;
> struct device *dev;
> + char stream_id_str[15];
A comment would be nice. Or better replace this with the array lookup,
it's much easier than snprintf.
> int i, rc;
>
> ctrl = container_of(msm_dp_ctrl, struct msm_dp_ctrl_private,
> msm_dp_ctrl);
> @@ -2710,9 +2709,19 @@ static int msm_dp_ctrl_clk_init(struct msm_dp_ctrl
> *msm_dp_ctrl)
> if (rc)
> return rc;
>
> - ctrl->pixel_clk = devm_clk_get(dev, "stream_pixel");
> - if (IS_ERR(ctrl->pixel_clk))
> - return PTR_ERR(ctrl->pixel_clk);
> + ctrl->pixel_clk[DP_STREAM_0] = devm_clk_get(dev, "stream_pixel");
> + if (IS_ERR(ctrl->pixel_clk[DP_STREAM_0]))
> + return PTR_ERR(ctrl->pixel_clk[DP_STREAM_0]);
> +
> + for (i = DP_STREAM_1; i < max_stream; i++) {
> + sprintf(stream_id_str, "stream_%d_pixel", i);
> + ctrl->pixel_clk[i] = devm_clk_get(dev, stream_id_str);
> +
> + if (IS_ERR(ctrl->pixel_clk[i])) {
> + DRM_DEBUG_DP("failed to get stream %d pixel clock", i);
> + break;
> + }
> + }
>
> return 0;
> }
--
With best wishes
Dmitry
