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Signed-off-by: Jessica Zhang Signed-off-by: Dmitry Baryshkov --- drivers/gpu/drm/msm/dp/dp_display.c | 60 +++++++++++++++++++++++++++++++++= ++++ drivers/gpu/drm/msm/dp/dp_drm.c | 20 ------------- drivers/gpu/drm/msm/dp/dp_drm.h | 2 ++ 3 files changed, 62 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/d= p_display.c index 5997cd28ba11..a05144de3b93 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -1151,6 +1151,66 @@ static int msm_dp_hpd_event_thread_start(struct msm_= dp_display_private *msm_dp_p return 0; } =20 +/** + * msm_dp_bridge_detect - callback to determine if connector is connected + * @bridge: Pointer to drm bridge structure + * @connector: Pointer to drm connector structure + * Returns: Bridge's 'is connected' status + */ +enum drm_connector_status msm_dp_bridge_detect(struct drm_bridge *bridge, + struct drm_connector *connector) +{ + struct msm_dp_bridge *msm_dp_bridge =3D to_dp_bridge(bridge); + struct msm_dp *dp =3D msm_dp_bridge->msm_dp_display; + struct msm_dp_display_private *priv; + int ret =3D 0; + int status =3D connector_status_disconnected; + u8 dpcd[DP_RECEIVER_CAP_SIZE]; + struct drm_dp_desc desc; + + dp =3D to_dp_bridge(bridge)->msm_dp_display; + + priv =3D container_of(dp, struct msm_dp_display_private, msm_dp_display); + + if (!dp->link_ready) + return status; + + msm_dp_aux_enable_xfers(priv->aux, true); + + ret =3D pm_runtime_resume_and_get(&dp->pdev->dev); + if (ret) { + DRM_ERROR("failed to pm_runtime_resume\n"); + msm_dp_aux_enable_xfers(priv->aux, false); + return status; + } + + ret =3D msm_dp_aux_is_link_connected(priv->aux); + if (dp->internal_hpd && !ret) + goto end; + + ret =3D drm_dp_read_dpcd_caps(priv->aux, dpcd); + if (ret) + goto end; + + ret =3D drm_dp_read_desc(priv->aux, &desc, drm_dp_is_branch(dpcd)); + if (ret) + goto end; + + status =3D connector_status_connected; + if (drm_dp_read_sink_count_cap(connector, dpcd, &desc)) { + int sink_count =3D drm_dp_read_sink_count(priv->aux); + + drm_dbg_dp(dp->drm_dev, "sink_count =3D %d\n", sink_count); + + if (sink_count <=3D 0) + status =3D connector_status_disconnected; + } + +end: + pm_runtime_put_sync(&dp->pdev->dev); + return status; +} + static irqreturn_t msm_dp_display_irq_handler(int irq, void *dev_id) { struct msm_dp_display_private *dp =3D dev_id; diff --git a/drivers/gpu/drm/msm/dp/dp_drm.c b/drivers/gpu/drm/msm/dp/dp_dr= m.c index fd6443d2b6ce..e4622c85fb66 100644 --- a/drivers/gpu/drm/msm/dp/dp_drm.c +++ b/drivers/gpu/drm/msm/dp/dp_drm.c @@ -15,26 +15,6 @@ #include "dp_audio.h" #include "dp_drm.h" =20 -/** - * msm_dp_bridge_detect - callback to determine if connector is connected - * @bridge: Pointer to drm bridge structure - * @connector: Pointer to drm connector structure - * Returns: Bridge's 'is connected' status - */ -static enum drm_connector_status -msm_dp_bridge_detect(struct drm_bridge *bridge, struct drm_connector *conn= ector) -{ - struct msm_dp *dp; - - dp =3D to_dp_bridge(bridge)->msm_dp_display; - - drm_dbg_dp(dp->drm_dev, "link_ready =3D %s\n", - str_true_false(dp->link_ready)); - - return (dp->link_ready) ? connector_status_connected : - connector_status_disconnected; -} - static int msm_dp_bridge_atomic_check(struct drm_bridge *bridge, struct drm_bridge_state *bridge_state, struct drm_crtc_state *crtc_state, diff --git a/drivers/gpu/drm/msm/dp/dp_drm.h b/drivers/gpu/drm/msm/dp/dp_dr= m.h index 9eb3431dd93a..6c0426803d78 100644 --- a/drivers/gpu/drm/msm/dp/dp_drm.h +++ b/drivers/gpu/drm/msm/dp/dp_drm.h @@ -25,6 +25,8 @@ int msm_dp_bridge_init(struct msm_dp *msm_dp_display, str= uct drm_device *dev, struct drm_encoder *encoder, bool yuv_supported); =20 +enum drm_connector_status msm_dp_bridge_detect(struct drm_bridge *bridge, + struct drm_connector *connector); void msm_dp_bridge_atomic_enable(struct drm_bridge *drm_bridge, struct drm_atomic_state *state); void msm_dp_bridge_atomic_disable(struct drm_bridge *drm_bridge, --=20 2.47.3