Re: [PATCH 5/7] drm/msm/dp: Implement hpd_notify()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 10/08/2022 06:50, Bjorn Andersson wrote:
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 <bjorn.andersson@xxxxxxxxxx>
---
  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));

Not used anymore, isn't it? Then dp_display->dev also seems unused.

+
  	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_ */

--
With best wishes
Dmitry




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux