drm/msm/dp: Move link training to atomic_enable()

Currently, the DP link training is being done during HPD. Move
link training to atomic_enable() in accordance with the atomic_enable()
documentation.

Link disabling is already done in atomic_post_disable() (as part of the
dp_ctrl_off_link_stream() helper).

Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com>
Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455
Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Acked-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/727606/
Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-4-cf3ab488dd7b@oss.qualcomm.com

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 77f1ae5d7210006cf4f0b2358ebf1370984a734d..1745735b3eb27afe36c93618a2a2153e8c1f8af2 100644 (file)
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -437,11 +437,6 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
        msm_dp_link_psm_config(dp->link, &dp->panel->link_info, false);
 
        msm_dp_link_reset_phy_params_vx_px(dp->link);
-       rc = msm_dp_ctrl_on_link(dp->ctrl);
-       if (rc) {
-               DRM_ERROR("failed to complete DP link training\n");
-               goto end;
-       }
 
        msm_dp_add_event(dp, EV_USER_NOTIFICATION, true, 0);
 
@@ -1699,6 +1694,13 @@ void msm_dp_bridge_atomic_enable(struct drm_bridge *drm_bridge,
                force_link_train = true;
        }
 
+       rc = msm_dp_ctrl_on_link(msm_dp_display->ctrl);
+       if (rc) {
+               DRM_ERROR("Failed link training (rc=%d)\n", rc);
+               // TODO: schedule drm_connector_set_link_status_property()
+               return;
+       }
+
        msm_dp_display_enable(msm_dp_display, force_link_train);
 
        rc = msm_dp_display_post_enable(dp);