[PATCH 0/6] drm: handle IRQ_HPD events correctly

[PATCH 0/6] drm: handle IRQ_HPD events correctly

[Dmitry Baryshkov]

Both DisplayPort and HDMI standards define a way for the Sink / display
to notify the Source / host about some kinds of events. In case of HDMI
it's as simple as singnalling changes to the EDID. In case of
DisplayPort it's more complicated and requires actual checking of the
DPCD registers.

Currently USB-C drivers don't have a way to deliver the IRQ_HPD
notifications, leading to missing MST notifications. Provide necessary
plumbing to let IRQ_HPD events be passed to the DisplayPort drivers.

Note: the Yoga C630 UCSI driver and Acer Aspire1 EC driver are not yet
enabled to send the IRQ_HPD events. Both of them would need some more
reverse engineering to find out how the event is being reported by the
EC.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
Dmitry Baryshkov (6):
      drm/connector: report IRQ_HPD events to drm_connector_oob_hotplug_event()
      drm/bridge: pass down IRQ_HPD to the drivers
      drm/bridge: aux-hpd: let drivers pass IRQ_HPD events
      drm/msm: dp: handle the IRQ_HPD events reported by USB-C
      soc: qcom: pmic-glink-altmode: pass down HPD_IRQ events
      usb: typec: ucsi: huawei-gaokun: pass down HPD_IRQ events

 drivers/gpu/drm/bridge/aux-hpd-bridge.c        |  9 +++++---
 drivers/gpu/drm/bridge/chrontel-ch7033.c       |  2 +-
 drivers/gpu/drm/bridge/lontium-lt8912b.c       |  2 +-
 drivers/gpu/drm/bridge/lontium-lt9611uxc.c     |  3 ++-
 drivers/gpu/drm/bridge/ti-tfp410.c             |  2 +-
 drivers/gpu/drm/display/drm_bridge_connector.c | 21 ++++++++++--------
 drivers/gpu/drm/drm_bridge.c                   | 18 ++++++++++------
 drivers/gpu/drm/drm_connector.c                |  6 ++++--
 drivers/gpu/drm/i915/display/intel_dp.c        |  3 ++-
 drivers/gpu/drm/meson/meson_encoder_hdmi.c     |  3 ++-
 drivers/gpu/drm/msm/dp/dp_display.c            |  6 +++++-
 drivers/gpu/drm/msm/dp/dp_drm.h                |  3 ++-
 drivers/gpu/drm/omapdrm/dss/hdmi4.c            |  3 ++-
 drivers/soc/qcom/pmic_glink_altmode.c          |  4 +++-
 drivers/usb/typec/altmodes/displayport.c       | 12 +++++++----
 drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c    |  9 ++++----
 include/drm/bridge/aux-bridge.h                | 13 +++++++++--
 include/drm/drm_bridge.h                       | 30 +++++++++++++++++++++-----
 include/drm/drm_connector.h                    |  6 ++++--
 19 files changed, 107 insertions(+), 48 deletions(-)
---
base-commit: 66672af7a095d89f082c5327f3b15bc2f93d558e
change-id: 20260414-hpd-irq-events-e72bc076a5f1

Best regards,
--  
With best wishes
Dmitry

[PATCH 1/6] drm/connector: report IRQ_HPD events to drm_connector_oob_hotplug_event()

[Dmitry Baryshkov]

The DisplayPort standard defines a special kind of events called IRQ.
These events are used to notify DP Source about the events on the Sink
side. It is extremely important for DP MST handling, where the MST
events are reported through this IRQ.

In case of the USB-C DP AltMode there is no actual HPD pulse, but the
events are ported through the bits in the AltMode VDOs.

Extend the drm_connector_oob_hotplug_event() interface and report IRQ
events to the DisplayPort Sink drivers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/gpu/drm/drm_connector.c          |  4 +++-
 drivers/usb/typec/altmodes/displayport.c | 12 ++++++++----
 include/drm/drm_connector.h              |  3 ++-
 3 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 47dc53c4a738..5fdacbd84bd7 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -3510,6 +3510,7 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
  * drm_connector_oob_hotplug_event - Report out-of-band hotplug event to connector
  * @connector_fwnode: fwnode_handle to report the event on
  * @status: hot plug detect logical state
+ * @irq_hpd: HPD pulse detected
  *
  * On some hardware a hotplug event notification may come from outside the display
  * driver / device. An example of this is some USB Type-C setups where the hardware
@@ -3520,7 +3521,8 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
  * a drm_connector reference through calling drm_connector_find_by_fwnode().
  */
 void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode,
-				     enum drm_connector_status status)
+				     enum drm_connector_status status,
+				     bool irq_hpd)
 {
 	struct drm_connector *connector;
 
diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
index 35d9c3086990..0cade62da905 100644
--- a/drivers/usb/typec/altmodes/displayport.c
+++ b/drivers/usb/typec/altmodes/displayport.c
@@ -189,7 +189,8 @@ static int dp_altmode_status_update(struct dp_altmode *dp)
 	} else {
 		drm_connector_oob_hotplug_event(dp->connector_fwnode,
 						hpd ? connector_status_connected :
-						      connector_status_disconnected);
+						      connector_status_disconnected,
+						hpd && irq_hpd);
 		dp->hpd = hpd;
 		sysfs_notify(&dp->alt->dev.kobj, "displayport", "hpd");
 		if (hpd && irq_hpd) {
@@ -212,7 +213,8 @@ static int dp_altmode_configured(struct dp_altmode *dp)
 	 */
 	if (dp->pending_hpd) {
 		drm_connector_oob_hotplug_event(dp->connector_fwnode,
-						connector_status_connected);
+						connector_status_connected,
+						dp->pending_irq_hpd);
 		sysfs_notify(&dp->alt->dev.kobj, "displayport", "hpd");
 		dp->pending_hpd = false;
 		if (dp->pending_irq_hpd) {
@@ -397,7 +399,8 @@ static int dp_altmode_vdm(struct typec_altmode *alt,
 			dp->data.conf = 0;
 			if (dp->hpd) {
 				drm_connector_oob_hotplug_event(dp->connector_fwnode,
-								connector_status_disconnected);
+								connector_status_disconnected,
+								false);
 				dp->hpd = false;
 				sysfs_notify(&dp->alt->dev.kobj, "displayport", "hpd");
 			}
@@ -827,7 +830,8 @@ void dp_altmode_remove(struct typec_altmode *alt)
 
 	if (dp->connector_fwnode) {
 		drm_connector_oob_hotplug_event(dp->connector_fwnode,
-						connector_status_disconnected);
+						connector_status_disconnected,
+						false);
 
 		fwnode_handle_put(dp->connector_fwnode);
 	}
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index f83f28cae207..e8e7e6c9eb5c 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -2521,7 +2521,8 @@ drm_connector_is_unregistered(struct drm_connector *connector)
 }
 
 void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode,
-				     enum drm_connector_status status);
+				     enum drm_connector_status status,
+				     bool irq_hpd);
 const char *drm_get_connector_type_name(unsigned int connector_type);
 const char *drm_get_connector_status_name(enum drm_connector_status status);
 const char *drm_get_subpixel_order_name(enum subpixel_order order);

-- 
2.47.3

[PATCH 2/6] drm/bridge: pass down IRQ_HPD to the drivers

[Dmitry Baryshkov]

Pass down the notifications about the IRQ_HPD events down to the
individual drivers, letting them handle those as required.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/gpu/drm/bridge/chrontel-ch7033.c       |  2 +-
 drivers/gpu/drm/bridge/lontium-lt8912b.c       |  2 +-
 drivers/gpu/drm/bridge/lontium-lt9611uxc.c     |  3 ++-
 drivers/gpu/drm/bridge/ti-tfp410.c             |  2 +-
 drivers/gpu/drm/display/drm_bridge_connector.c | 21 ++++++++++++---------
 drivers/gpu/drm/drm_bridge.c                   |  5 +++--
 drivers/gpu/drm/drm_connector.c                |  2 +-
 drivers/gpu/drm/i915/display/intel_dp.c        |  3 ++-
 drivers/gpu/drm/meson/meson_encoder_hdmi.c     |  3 ++-
 drivers/gpu/drm/msm/dp/dp_display.c            |  3 ++-
 drivers/gpu/drm/msm/dp/dp_drm.h                |  3 ++-
 drivers/gpu/drm/omapdrm/dss/hdmi4.c            |  3 ++-
 include/drm/drm_bridge.h                       |  8 +++++---
 include/drm/drm_connector.h                    |  3 ++-
 14 files changed, 38 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/bridge/chrontel-ch7033.c b/drivers/gpu/drm/bridge/chrontel-ch7033.c
index 54d49d4882c8..6d932dbe062b 100644
--- a/drivers/gpu/drm/bridge/chrontel-ch7033.c
+++ b/drivers/gpu/drm/bridge/chrontel-ch7033.c
@@ -259,7 +259,7 @@ static const struct drm_connector_helper_funcs ch7033_connector_helper_funcs = {
 	.best_encoder = ch7033_connector_best_encoder,
 };
 
-static void ch7033_hpd_event(void *arg, enum drm_connector_status status)
+static void ch7033_hpd_event(void *arg, enum drm_connector_status status, bool irq_hpd)
 {
 	struct ch7033_priv *priv = arg;
 
diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c
index 8a0b48efca58..3ffbb7346418 100644
--- a/drivers/gpu/drm/bridge/lontium-lt8912b.c
+++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c
@@ -504,7 +504,7 @@ static int lt8912_attach_dsi(struct lt8912 *lt)
 	return 0;
 }
 
-static void lt8912_bridge_hpd_cb(void *data, enum drm_connector_status status)
+static void lt8912_bridge_hpd_cb(void *data, enum drm_connector_status status, bool irq_hpd)
 {
 	struct lt8912 *lt = data;
 
diff --git a/drivers/gpu/drm/bridge/lontium-lt9611uxc.c b/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
index 11aab07d88df..7e5a110cfa1f 100644
--- a/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
@@ -430,7 +430,8 @@ static const struct drm_edid *lt9611uxc_bridge_edid_read(struct drm_bridge *brid
 
 static void lt9611uxc_bridge_hpd_notify(struct drm_bridge *bridge,
 					struct drm_connector *connector,
-					enum drm_connector_status status)
+					enum drm_connector_status status,
+					bool irq_hpd)
 {
 	const struct drm_edid *drm_edid;
 
diff --git a/drivers/gpu/drm/bridge/ti-tfp410.c b/drivers/gpu/drm/bridge/ti-tfp410.c
index 3b6b0e92cf89..4111aa104256 100644
--- a/drivers/gpu/drm/bridge/ti-tfp410.c
+++ b/drivers/gpu/drm/bridge/ti-tfp410.c
@@ -110,7 +110,7 @@ static void tfp410_hpd_work_func(struct work_struct *work)
 		drm_helper_hpd_irq_event(dvi->bridge.dev);
 }
 
-static void tfp410_hpd_callback(void *arg, enum drm_connector_status status)
+static void tfp410_hpd_callback(void *arg, enum drm_connector_status status, bool irq_hpd)
 {
 	struct tfp410 *dvi = arg;
 
diff --git a/drivers/gpu/drm/display/drm_bridge_connector.c b/drivers/gpu/drm/display/drm_bridge_connector.c
index 39cc18f78eda..749d3d63216c 100644
--- a/drivers/gpu/drm/display/drm_bridge_connector.c
+++ b/drivers/gpu/drm/display/drm_bridge_connector.c
@@ -141,7 +141,8 @@ struct drm_bridge_connector {
  */
 
 static void drm_bridge_connector_hpd_notify(struct drm_connector *connector,
-					    enum drm_connector_status status)
+					    enum drm_connector_status status,
+					    bool irq_hpd)
 {
 	struct drm_bridge_connector *bridge_connector =
 		to_drm_bridge_connector(connector);
@@ -149,12 +150,12 @@ static void drm_bridge_connector_hpd_notify(struct drm_connector *connector,
 	/* Notify all bridges in the pipeline of hotplug events. */
 	drm_for_each_bridge_in_chain_scoped(bridge_connector->encoder, bridge) {
 		if (bridge->funcs->hpd_notify)
-			bridge->funcs->hpd_notify(bridge, connector, status);
+			bridge->funcs->hpd_notify(bridge, connector, status, irq_hpd);
 	}
 }
 
 static void drm_bridge_connector_handle_hpd(struct drm_bridge_connector *drm_bridge_connector,
-					    enum drm_connector_status status)
+					    enum drm_connector_status status, bool irq_hpd)
 {
 	struct drm_connector *connector = &drm_bridge_connector->base;
 	struct drm_device *dev = connector->dev;
@@ -163,24 +164,26 @@ static void drm_bridge_connector_handle_hpd(struct drm_bridge_connector *drm_bri
 	connector->status = status;
 	mutex_unlock(&dev->mode_config.mutex);
 
-	drm_bridge_connector_hpd_notify(connector, status);
+	drm_bridge_connector_hpd_notify(connector, status, irq_hpd);
 
 	drm_kms_helper_connector_hotplug_event(connector);
 }
 
 static void drm_bridge_connector_hpd_cb(void *cb_data,
-					enum drm_connector_status status)
+					enum drm_connector_status status,
+					bool irq_hpd)
 {
-	drm_bridge_connector_handle_hpd(cb_data, status);
+	drm_bridge_connector_handle_hpd(cb_data, status, irq_hpd);
 }
 
 static void drm_bridge_connector_oob_hotplug_event(struct drm_connector *connector,
-						   enum drm_connector_status status)
+						   enum drm_connector_status status,
+						   bool irq_hpd)
 {
 	struct drm_bridge_connector *bridge_connector =
 		to_drm_bridge_connector(connector);
 
-	drm_bridge_connector_handle_hpd(bridge_connector, status);
+	drm_bridge_connector_handle_hpd(bridge_connector, status, irq_hpd);
 }
 
 static void drm_bridge_connector_enable_hpd(struct drm_connector *connector)
@@ -223,7 +226,7 @@ drm_bridge_connector_detect(struct drm_connector *connector, bool force)
 		if (hdmi)
 			drm_atomic_helper_connector_hdmi_hotplug(connector, status);
 
-		drm_bridge_connector_hpd_notify(connector, status);
+		drm_bridge_connector_hpd_notify(connector, status, false);
 	} else {
 		switch (connector->connector_type) {
 		case DRM_MODE_CONNECTOR_DPI:
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index d6f512b73389..9c44e9b6c638 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -1444,7 +1444,8 @@ EXPORT_SYMBOL_GPL(drm_bridge_edid_read);
  */
 void drm_bridge_hpd_enable(struct drm_bridge *bridge,
 			   void (*cb)(void *data,
-				      enum drm_connector_status status),
+				      enum drm_connector_status status,
+				      bool irq_hpd),
 			   void *data)
 {
 	if (!(bridge->ops & DRM_BRIDGE_OP_HPD))
@@ -1509,7 +1510,7 @@ void drm_bridge_hpd_notify(struct drm_bridge *bridge,
 {
 	mutex_lock(&bridge->hpd_mutex);
 	if (bridge->hpd_cb)
-		bridge->hpd_cb(bridge->hpd_data, status);
+		bridge->hpd_cb(bridge->hpd_data, status, false);
 	mutex_unlock(&bridge->hpd_mutex);
 }
 EXPORT_SYMBOL_GPL(drm_bridge_hpd_notify);
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 5fdacbd84bd7..809ce38c4822 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -3531,7 +3531,7 @@ void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode,
 		return;
 
 	if (connector->funcs->oob_hotplug_event)
-		connector->funcs->oob_hotplug_event(connector, status);
+		connector->funcs->oob_hotplug_event(connector, status, irq_hpd);
 
 	drm_connector_put(connector);
 }
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index b8b6d62fb275..524d6c67ca54 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -6784,7 +6784,8 @@ static int intel_dp_connector_atomic_check(struct drm_connector *_connector,
 }
 
 static void intel_dp_oob_hotplug_event(struct drm_connector *_connector,
-				       enum drm_connector_status hpd_state)
+				       enum drm_connector_status hpd_state,
+				       bool irq_hpd)
 {
 	struct intel_connector *connector = to_intel_connector(_connector);
 	struct intel_display *display = to_intel_display(connector);
diff --git a/drivers/gpu/drm/meson/meson_encoder_hdmi.c b/drivers/gpu/drm/meson/meson_encoder_hdmi.c
index 1abb0572bb5f..346c4d2e26e8 100644
--- a/drivers/gpu/drm/meson/meson_encoder_hdmi.c
+++ b/drivers/gpu/drm/meson/meson_encoder_hdmi.c
@@ -323,7 +323,8 @@ static int meson_encoder_hdmi_atomic_check(struct drm_bridge *bridge,
 
 static void meson_encoder_hdmi_hpd_notify(struct drm_bridge *bridge,
 					  struct drm_connector *connector,
-					  enum drm_connector_status status)
+					  enum drm_connector_status status,
+					  bool irq_hpd)
 {
 	struct meson_encoder_hdmi *encoder_hdmi = bridge_to_meson_encoder_hdmi(bridge);
 
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index d2124d625485..45e14a0010c2 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1785,7 +1785,8 @@ void msm_dp_bridge_hpd_disable(struct drm_bridge *bridge)
 
 void msm_dp_bridge_hpd_notify(struct drm_bridge *bridge,
 			      struct drm_connector *connector,
-			      enum drm_connector_status status)
+			      enum drm_connector_status status,
+			      bool irq_hpd)
 {
 	struct msm_dp_bridge *msm_dp_bridge = to_dp_bridge(bridge);
 	struct msm_dp *msm_dp_display = msm_dp_bridge->msm_dp_display;
diff --git a/drivers/gpu/drm/msm/dp/dp_drm.h b/drivers/gpu/drm/msm/dp/dp_drm.h
index 9eb3431dd93a..5a877655d56c 100644
--- a/drivers/gpu/drm/msm/dp/dp_drm.h
+++ b/drivers/gpu/drm/msm/dp/dp_drm.h
@@ -41,6 +41,7 @@ void msm_dp_bridge_hpd_enable(struct drm_bridge *bridge);
 void msm_dp_bridge_hpd_disable(struct drm_bridge *bridge);
 void msm_dp_bridge_hpd_notify(struct drm_bridge *bridge,
 			      struct drm_connector *connector,
-			      enum drm_connector_status status);
+			      enum drm_connector_status status,
+			      bool irq_hpd);
 
 #endif /* _DP_DRM_H_ */
diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi4.c b/drivers/gpu/drm/omapdrm/dss/hdmi4.c
index 29b2dfb90b5f..dae9e464889c 100644
--- a/drivers/gpu/drm/omapdrm/dss/hdmi4.c
+++ b/drivers/gpu/drm/omapdrm/dss/hdmi4.c
@@ -429,7 +429,8 @@ static void hdmi4_bridge_disable(struct drm_bridge *bridge,
 
 static void hdmi4_bridge_hpd_notify(struct drm_bridge *bridge,
 				    struct drm_connector *connector,
-				    enum drm_connector_status status)
+				    enum drm_connector_status status,
+				    bool irq_hpd)
 {
 	struct omap_hdmi *hdmi = drm_bridge_to_hdmi(bridge);
 
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index a8d67bd9ee50..4eea124c7eb7 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -615,7 +615,8 @@ struct drm_bridge_funcs {
 	 */
 	void (*hpd_notify)(struct drm_bridge *bridge,
 			   struct drm_connector *connector,
-			   enum drm_connector_status status);
+			   enum drm_connector_status status,
+			   bool irq_hpd);
 
 	/**
 	 * @hpd_enable:
@@ -1260,7 +1261,7 @@ struct drm_bridge {
 	 * @hpd_cb: Hot plug detection callback, registered with
 	 * drm_bridge_hpd_enable().
 	 */
-	void (*hpd_cb)(void *data, enum drm_connector_status status);
+	void (*hpd_cb)(void *data, enum drm_connector_status status, bool irq_hpd);
 	/**
 	 * @hpd_data: Private data passed to the Hot plug detection callback
 	 * @hpd_cb.
@@ -1550,7 +1551,8 @@ const struct drm_edid *drm_bridge_edid_read(struct drm_bridge *bridge,
 					    struct drm_connector *connector);
 void drm_bridge_hpd_enable(struct drm_bridge *bridge,
 			   void (*cb)(void *data,
-				      enum drm_connector_status status),
+				      enum drm_connector_status status,
+				      bool irq_hpd),
 			   void *data);
 void drm_bridge_hpd_disable(struct drm_bridge *bridge);
 void drm_bridge_hpd_notify(struct drm_bridge *bridge,
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index e8e7e6c9eb5c..e164b0dbaa47 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1704,7 +1704,8 @@ struct drm_connector_funcs {
 	 * has been received from a source outside the display driver / device.
 	 */
 	void (*oob_hotplug_event)(struct drm_connector *connector,
-				  enum drm_connector_status status);
+				  enum drm_connector_status status,
+				  bool irq_hpd);
 
 	/**
 	 * @debugfs_init:

-- 
2.47.3

[PATCH 3/6] drm/bridge: aux-hpd: let drivers pass IRQ_HPD events

[Dmitry Baryshkov]

Let users of aux-hpd, the UCSI and PMIC GLINK drivers pass the IRQ_HPD
events to the DisplayPort drivers.

The drm_aux_hpd_bridge_notify() is keps to ease merging of the series,
preventing extra cross-tree merges. It will be removed once all
drivers are converted. The drm_bridge_hpd_notify() function is kept for
the driver which only care about the connector status and will always
pass false as the irq_hpd event.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/gpu/drm/bridge/aux-hpd-bridge.c |  9 ++++++---
 drivers/gpu/drm/drm_bridge.c            | 15 +++++++++------
 include/drm/bridge/aux-bridge.h         | 13 +++++++++++--
 include/drm/drm_bridge.h                | 22 ++++++++++++++++++++--
 4 files changed, 46 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/bridge/aux-hpd-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-bridge.c
index f02a38a2638a..74d606b27dc6 100644
--- a/drivers/gpu/drm/bridge/aux-hpd-bridge.c
+++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.c
@@ -136,16 +136,19 @@ struct device *drm_dp_hpd_bridge_register(struct device *parent, struct device_n
 EXPORT_SYMBOL_GPL(drm_dp_hpd_bridge_register);
 
 /**
- * drm_aux_hpd_bridge_notify - notify hot plug detection events
+ * drm_aux_hpd_bridge_notify_with_irq - notify hot plug detection events
  * @dev: device created for the HPD bridge
  * @status: output connection status
+ * @irq_hpd: recorded IRQ_HPD status
  *
  * A wrapper around drm_bridge_hpd_notify() that is used to report hot plug
  * detection events for bridges created via drm_dp_hpd_bridge_register().
  *
  * This function shall be called in a context that can sleep.
  */
-void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status)
+void drm_aux_hpd_bridge_notify_with_irq(struct device *dev,
+					enum drm_connector_status status,
+					bool irq_hpd)
 {
 	struct auxiliary_device *adev = to_auxiliary_dev(dev);
 	struct drm_aux_hpd_bridge_data *data = auxiliary_get_drvdata(adev);
@@ -155,7 +158,7 @@ void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status sta
 
 	drm_bridge_hpd_notify(&data->bridge, status);
 }
-EXPORT_SYMBOL_GPL(drm_aux_hpd_bridge_notify);
+EXPORT_SYMBOL_GPL(drm_aux_hpd_bridge_notify_with_irq);
 
 static int drm_aux_hpd_bridge_attach(struct drm_bridge *bridge,
 				     struct drm_encoder *encoder,
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index 9c44e9b6c638..5a3dd4f92fbc 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -1495,25 +1495,28 @@ void drm_bridge_hpd_disable(struct drm_bridge *bridge)
 EXPORT_SYMBOL_GPL(drm_bridge_hpd_disable);
 
 /**
- * drm_bridge_hpd_notify - notify hot plug detection events
+ * drm_bridge_hpd_notify_with_irq - notify hot plug detection and sink IRQ events
  * @bridge: bridge control structure
  * @status: output connection status
+ * @irq_hpd: recorded IRQ_HPD status
  *
  * Bridge drivers shall call this function to report hot plug events when they
- * detect a change in the output status, when hot plug detection has been
+ * detect a change in the output status or when the sink has reported the IRQ
+ * event (usually delivered as IRQ_HPD pulse), when hot plug detection has been
  * enabled by drm_bridge_hpd_enable().
  *
  * This function shall be called in a context that can sleep.
  */
-void drm_bridge_hpd_notify(struct drm_bridge *bridge,
-			   enum drm_connector_status status)
+void drm_bridge_hpd_notify_with_irq(struct drm_bridge *bridge,
+				    enum drm_connector_status status,
+				    bool irq_hpd)
 {
 	mutex_lock(&bridge->hpd_mutex);
 	if (bridge->hpd_cb)
-		bridge->hpd_cb(bridge->hpd_data, status, false);
+		bridge->hpd_cb(bridge->hpd_data, status, irq_hpd);
 	mutex_unlock(&bridge->hpd_mutex);
 }
-EXPORT_SYMBOL_GPL(drm_bridge_hpd_notify);
+EXPORT_SYMBOL_GPL(drm_bridge_hpd_notify_with_irq);
 
 #ifdef CONFIG_OF
 /**
diff --git a/include/drm/bridge/aux-bridge.h b/include/drm/bridge/aux-bridge.h
index c2f5a855512f..6f837df90b2f 100644
--- a/include/drm/bridge/aux-bridge.h
+++ b/include/drm/bridge/aux-bridge.h
@@ -25,7 +25,9 @@ struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent, str
 int devm_drm_dp_hpd_bridge_add(struct device *dev, struct auxiliary_device *adev);
 struct device *drm_dp_hpd_bridge_register(struct device *parent,
 					  struct device_node *np);
-void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status);
+void drm_aux_hpd_bridge_notify_with_irq(struct device *dev,
+					enum drm_connector_status status,
+					bool irq_hpd);
 #else
 static inline struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent,
 								    struct device_node *np)
@@ -44,9 +46,16 @@ static inline struct device *drm_dp_hpd_bridge_register(struct device *parent,
 	return NULL;
 }
 
-static inline void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status)
+static inline void drm_aux_hpd_bridge_notify_with_irq(struct device *dev,
+						      enum drm_connector_status status,
+						      bool irq_hpd)
 {
 }
 #endif
 
+static inline void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status)
+{
+	drm_aux_hpd_bridge_notify_with_irq(dev, status, false);
+}
+
 #endif
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index 4eea124c7eb7..c3bb30133925 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -1555,8 +1555,26 @@ void drm_bridge_hpd_enable(struct drm_bridge *bridge,
 				      bool irq_hpd),
 			   void *data);
 void drm_bridge_hpd_disable(struct drm_bridge *bridge);
-void drm_bridge_hpd_notify(struct drm_bridge *bridge,
-			   enum drm_connector_status status);
+void drm_bridge_hpd_notify_with_irq(struct drm_bridge *bridge,
+				    enum drm_connector_status status,
+				    bool irq_hpd);
+
+/**
+ * drm_bridge_hpd_notify - notify hot plug detection events
+ * @bridge: bridge control structure
+ * @status: output connection status
+ *
+ * Bridge drivers shall call this function to report hot plug events when they
+ * detect a change in the output status, when hot plug detection has been
+ * enabled by drm_bridge_hpd_enable().
+ *
+ * This function shall be called in a context that can sleep.
+ */
+static inline void drm_bridge_hpd_notify(struct drm_bridge *bridge,
+					 enum drm_connector_status status)
+{
+	drm_bridge_hpd_notify_with_irq(bridge, status, false);
+}
 
 #ifdef CONFIG_DRM_PANEL_BRIDGE
 bool drm_bridge_is_panel(const struct drm_bridge *bridge);

-- 
2.47.3

[PATCH 4/6] drm/msm: dp: handle the IRQ_HPD events reported by USB-C

[Dmitry Baryshkov]

Let the MSM DisplayPort driver properly track and handle IRQ_HPD
delivered over the OOB events (e.g. from the USB-C AltMode handler).

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 45e14a0010c2..390a967a53f0 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1800,4 +1800,7 @@ void msm_dp_bridge_hpd_notify(struct drm_bridge *bridge,
 		msm_dp_add_event(dp, EV_HPD_PLUG_INT, 0, 0);
 	else if (msm_dp_display->link_ready && status == connector_status_disconnected)
 		msm_dp_add_event(dp, EV_HPD_UNPLUG_INT, 0, 0);
+
+	if (irq_hpd)
+		msm_dp_add_event(dp, EV_IRQ_HPD_INT, 0, 0);
 }

-- 
2.47.3

[PATCH 5/6] soc: qcom: pmic-glink-altmode: pass down HPD_IRQ events

[Dmitry Baryshkov]

Pass IRQ_HPD events to the HPD bridge, letting those to be delivered to
the DisplayPort driver.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/soc/qcom/pmic_glink_altmode.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/qcom/pmic_glink_altmode.c b/drivers/soc/qcom/pmic_glink_altmode.c
index 619bad2c27ee..618dce748316 100644
--- a/drivers/soc/qcom/pmic_glink_altmode.c
+++ b/drivers/soc/qcom/pmic_glink_altmode.c
@@ -373,7 +373,9 @@ static void pmic_glink_altmode_worker(struct work_struct *work)
 		else
 			conn_status = connector_status_disconnected;
 
-		drm_aux_hpd_bridge_notify(&alt_port->bridge->dev, conn_status);
+		drm_aux_hpd_bridge_notify_with_irq(&alt_port->bridge->dev,
+						   conn_status,
+						   alt_port->hpd_irq);
 	} else if (alt_port->mux_ctrl == MUX_CTRL_STATE_TUNNELING) {
 		if (alt_port->svid == USB_TYPEC_TBT_SID)
 			pmic_glink_altmode_enable_tbt(altmode, alt_port);

-- 
2.47.3

[PATCH 6/6] usb: typec: ucsi: huawei-gaokun: pass down HPD_IRQ events

[Dmitry Baryshkov]

Pass IRQ_HPD events to the HPD bridge, letting those to be delivered to
the DisplayPort driver.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c b/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c
index ca749fde49bd..328ba92e1b44 100644
--- a/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c
+++ b/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c
@@ -299,10 +299,11 @@ static void gaokun_ucsi_handle_altmode(struct gaokun_ucsi_port *port)
 
 	/* UCSI callback .connector_status() have set orientation */
 	if (port->bridge)
-		drm_aux_hpd_bridge_notify(&port->bridge->dev,
-					  port->hpd_state ?
-					  connector_status_connected :
-					  connector_status_disconnected);
+		drm_aux_hpd_bridge_notify_with_irq(&port->bridge->dev,
+						   port->hpd_state ?
+						   connector_status_connected :
+						   connector_status_disconnected,
+						   port->hpd_irq);
 
 	gaokun_ec_ucsi_pan_ack(uec->ec, port->idx);
 }

-- 
2.47.3

Re: [PATCH 1/6] drm/connector: report IRQ_HPD events to drm_connector_oob_hotplug_event()

[Tomi Valkeinen]

Hi,

On 16/04/2026 02:22, Dmitry Baryshkov wrote:
> The DisplayPort standard defines a special kind of events called IRQ.
> These events are used to notify DP Source about the events on the Sink
> side. It is extremely important for DP MST handling, where the MST
> events are reported through this IRQ.
> 
> In case of the USB-C DP AltMode there is no actual HPD pulse, but the
> events are ported through the bits in the AltMode VDOs.
> 
> Extend the drm_connector_oob_hotplug_event() interface and report IRQ
> events to the DisplayPort Sink drivers.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
> ---
>   drivers/gpu/drm/drm_connector.c          |  4 +++-
>   drivers/usb/typec/altmodes/displayport.c | 12 ++++++++----
>   include/drm/drm_connector.h              |  3 ++-
>   3 files changed, 13 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index 47dc53c4a738..5fdacbd84bd7 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -3510,6 +3510,7 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
>    * drm_connector_oob_hotplug_event - Report out-of-band hotplug event to connector
>    * @connector_fwnode: fwnode_handle to report the event on
>    * @status: hot plug detect logical state
> + * @irq_hpd: HPD pulse detected
>    *
>    * On some hardware a hotplug event notification may come from outside the display
>    * driver / device. An example of this is some USB Type-C setups where the hardware
> @@ -3520,7 +3521,8 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
>    * a drm_connector reference through calling drm_connector_find_by_fwnode().
>    */
>   void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode,
> -				     enum drm_connector_status status)
> +				     enum drm_connector_status status,
> +				     bool irq_hpd)
I find the "IRQ HPD" naming always confusing, even if I'm somewhat 
familiar with DP, but if someone has mainly worked on HDMI, I'm sure 
it's even worse.

Can we define this a bit more precisely? Is 'irq_hpd' only for 
displayport?  If so, perhaps 'dp_irq_hpd' or 'displayport_irq_hpd'. I 
might even call it 'dp_hpd_pulse', but maybe that's not good as the spec 
talks about HPD pulse for both short and long ones (although in the 
kernel doc you just write "HPD pulse")... The kernel doc could be 
expanded a bit to make it clear what this flag indicates.

  Tomi

Re: [PATCH 6/6] usb: typec: ucsi: huawei-gaokun: pass down HPD_IRQ events

[Heikki Krogerus]

Thu, Apr 16, 2026 at 02:22:37AM +0300, Dmitry Baryshkov kirjoitti:
> Pass IRQ_HPD events to the HPD bridge, letting those to be delivered to
> the DisplayPort driver.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
>  drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c b/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c
> index ca749fde49bd..328ba92e1b44 100644
> --- a/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c
> +++ b/drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c
> @@ -299,10 +299,11 @@ static void gaokun_ucsi_handle_altmode(struct gaokun_ucsi_port *port)
>  
>  	/* UCSI callback .connector_status() have set orientation */
>  	if (port->bridge)
> -		drm_aux_hpd_bridge_notify(&port->bridge->dev,
> -					  port->hpd_state ?
> -					  connector_status_connected :
> -					  connector_status_disconnected);
> +		drm_aux_hpd_bridge_notify_with_irq(&port->bridge->dev,
> +						   port->hpd_state ?
> +						   connector_status_connected :
> +						   connector_status_disconnected,
> +						   port->hpd_irq);
>  
>  	gaokun_ec_ucsi_pan_ack(uec->ec, port->idx);
>  }
> 
> -- 
> 2.47.3

-- 
heikki

Re: [PATCH 6/6] usb: typec: ucsi: huawei-gaokun: pass down HPD_IRQ events

[Pengyu Luo]

On Thu, Apr 16, 2026 at 7:22 AM Dmitry Baryshkov
<dmitry.baryshkov@oss.qualcomm.com> wrote:
>
> Pass IRQ_HPD events to the HPD bridge, letting those to be delivered to
> the DisplayPort driver.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Reviewed-by: Pengyu Luo <mitltlatltl@gmail.com>

Best wishes,
Pengyu