The DisplayPort controller's hot-plug mechanism is based on pinmuxing a physical signal no a GPIO pin into the controller. This is not always possible, either because there aren't dedicated GPIOs available or because the hot-plug signal is a virtual notification, in cases such as USB Type-C.
For these cases, by implementing the hpd_notify() callback for the DisplayPort controller's drm_bridge, a downstream drm_bridge (next_bridge) can be used to track and signal the connection status changes. This makes it possible to use downstream drm_bridges such as display-connector or any virtual mechanism, as long as they are implemented as a drm_bridge. Signed-off-by: Bjorn Andersson <[email protected]> --- drivers/gpu/drm/msm/dp/dp_display.c | 23 +++++++++++++++++++++++ drivers/gpu/drm/msm/dp/dp_display.h | 1 + drivers/gpu/drm/msm/dp/dp_drm.c | 3 +++ drivers/gpu/drm/msm/dp/dp_drm.h | 2 ++ 4 files changed, 29 insertions(+) diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index 699f28f2251e..568295381246 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -1303,6 +1303,7 @@ static int dp_display_probe(struct platform_device *pdev) if (!desc) return -EINVAL; + dp->dp_display.dev = &pdev->dev; dp->pdev = pdev; dp->name = "drm_dp"; dp->id = desc->id; @@ -1765,3 +1766,25 @@ void dp_bridge_mode_set(struct drm_bridge *drm_bridge, dp_display->dp_mode.h_active_low = !!(dp_display->dp_mode.drm_mode.flags & DRM_MODE_FLAG_NHSYNC); } + +void dp_bridge_hpd_notify(struct drm_bridge *bridge, + enum drm_connector_status status) +{ + struct msm_dp_bridge *dp_bridge = to_dp_bridge(bridge); + struct msm_dp *dp_display = dp_bridge->dp_display; + struct dp_display_private *dp = container_of(dp_display, struct dp_display_private, dp_display); + + /* Without next_bridge interrupts are handled by the DP core directly */ + if (!dp_display->next_bridge) + return; + + if (!dp->core_initialized) { + drm_dbg_dp(dp->drm_dev, "not initialized\n"); + return; + } + + if (!dp_display->is_connected && status == connector_status_connected) + dp_add_event(dp, EV_HPD_PLUG_INT, 0, 0); + else if (dp_display->is_connected && status == connector_status_disconnected) + dp_add_event(dp, EV_HPD_UNPLUG_INT, 0, 0); +} diff --git a/drivers/gpu/drm/msm/dp/dp_display.h b/drivers/gpu/drm/msm/dp/dp_display.h index dcedf021f7fe..d7bc537ead31 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.h +++ b/drivers/gpu/drm/msm/dp/dp_display.h @@ -11,6 +11,7 @@ #include "disp/msm_disp_snapshot.h" struct msm_dp { + struct device *dev; struct drm_device *drm_dev; struct device *codec_dev; struct drm_bridge *bridge; diff --git a/drivers/gpu/drm/msm/dp/dp_drm.c b/drivers/gpu/drm/msm/dp/dp_drm.c index 6df25f7662e7..875b23910bef 100644 --- a/drivers/gpu/drm/msm/dp/dp_drm.c +++ b/drivers/gpu/drm/msm/dp/dp_drm.c @@ -68,6 +68,7 @@ static const struct drm_bridge_funcs dp_bridge_ops = { .mode_valid = dp_bridge_mode_valid, .get_modes = dp_bridge_get_modes, .detect = dp_bridge_detect, + .hpd_notify = dp_bridge_hpd_notify, }; struct drm_bridge *dp_bridge_init(struct msm_dp *dp_display, struct drm_device *dev, @@ -138,6 +139,8 @@ struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display, struct dr if (IS_ERR(connector)) return connector; + connector->fwnode = fwnode_handle_get(dev_fwnode(dp_display->dev)); + drm_connector_attach_encoder(connector, encoder); return connector; diff --git a/drivers/gpu/drm/msm/dp/dp_drm.h b/drivers/gpu/drm/msm/dp/dp_drm.h index 82035dbb0578..79e6b2cf2d25 100644 --- a/drivers/gpu/drm/msm/dp/dp_drm.h +++ b/drivers/gpu/drm/msm/dp/dp_drm.h @@ -32,5 +32,7 @@ enum drm_mode_status dp_bridge_mode_valid(struct drm_bridge *bridge, void dp_bridge_mode_set(struct drm_bridge *drm_bridge, const struct drm_display_mode *mode, const struct drm_display_mode *adjusted_mode); +void dp_bridge_hpd_notify(struct drm_bridge *bridge, + enum drm_connector_status status); #endif /* _DP_DRM_H_ */ -- 2.35.1
