[PATCH v6 06/10] drm/display/hdmi: implement hotplug functions

[Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>]

The HDMI Connectors need to perform a variety of tasks when the HDMI
connector state changes. Such tasks include setting or invalidating CEC
address, notifying HDMI codec driver, updating scrambler data, etc.

Implementing such tasks in a driver-specific callbacks is error prone.
Start implementing the generic helper function (currently handling only
the HDMI Codec framework) to be used by drivers utilizing HDMI Connector
framework.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
 drivers/gpu/drm/display/drm_hdmi_state_helper.c | 61 +++++++++++++++++++++++++
 include/drm/display/drm_hdmi_state_helper.h     |  8 ++++
 2 files changed, 69 insertions(+)

diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
index 80bf2829ba89b5f84fed4fa9eb1d6302e10a4f9e..4cdeb63688b9e48acd8e8ae87a45b6253f7dd12b 100644
--- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
+++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
@@ -769,3 +769,64 @@ drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector *con
 	return ret;
 }
 EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_clear_audio_infoframe);
+
+/**
+ * drm_atomic_helper_connector_hdmi_hotplug_edid - Handle the hotplug event for the HDMI connector passing custom EDID
+ * @connector: A pointer to the HDMI connector
+ * @status: Connection status
+ * @drm_edid: EDID to process
+ *
+ * This function should be called as a part of the .detect() / .detect_ctx()
+ * and .force() callbacks, updating the HDMI-specific connector's data. Most
+ * drivers should be able to use @drm_atomic_helper_connector_hdmi_hotplug()
+ * instead.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int
+drm_atomic_helper_connector_hdmi_hotplug_edid(struct drm_connector *connector,
+					      enum drm_connector_status status,
+					      const struct drm_edid *drm_edid)
+{
+	if (status == connector_status_disconnected) {
+		// TODO: also handle CEC and scramber, HDMI sink disconnected.
+		drm_connector_hdmi_codec_plugged_notify(connector, false);
+	}
+
+	drm_edid_connector_update(connector, drm_edid);
+
+	if (status == connector_status_connected) {
+		// TODO: also handle CEC and scramber, HDMI sink is now connected.
+		drm_connector_hdmi_codec_plugged_notify(connector, true);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_hotplug_edid);
+
+/**
+ * drm_atomic_helper_connector_hdmi_hotplug - Handle the hotplug event for the HDMI connector
+ * @connector: A pointer to the HDMI connector
+ * @status: Connection status
+ *
+ * This function should be called as a part of the .detect() / .detect_ctx()
+ * and .force() callbacks, updating the HDMI-specific connector's data.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int
+drm_atomic_helper_connector_hdmi_hotplug(struct drm_connector *connector,
+					 enum drm_connector_status status)
+{
+	const struct drm_edid *drm_edid;
+	int ret;
+
+	drm_edid = drm_edid_read(connector);
+	ret = drm_atomic_helper_connector_hdmi_hotplug_edid(connector, status, drm_edid);
+	drm_edid_free(drm_edid);
+
+	return ret;
+}
+EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_hotplug);
diff --git a/include/drm/display/drm_hdmi_state_helper.h b/include/drm/display/drm_hdmi_state_helper.h
index d6d65da6d8f9ee46de33114cce2d6fbe6098a862..4ffd40d73d50d89449508b7a5ce5836a596638a1 100644
--- a/include/drm/display/drm_hdmi_state_helper.h
+++ b/include/drm/display/drm_hdmi_state_helper.h
@@ -6,8 +6,11 @@
 struct drm_atomic_state;
 struct drm_connector;
 struct drm_connector_state;
+struct drm_edid;
 struct hdmi_audio_infoframe;
 
+enum drm_connector_status;
+
 void __drm_atomic_helper_connector_hdmi_reset(struct drm_connector *connector,
 					      struct drm_connector_state *new_conn_state);
 
@@ -19,6 +22,11 @@ int drm_atomic_helper_connector_hdmi_update_audio_infoframe(struct drm_connector
 int drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector *connector);
 int drm_atomic_helper_connector_hdmi_update_infoframes(struct drm_connector *connector,
 						       struct drm_atomic_state *state);
+int drm_atomic_helper_connector_hdmi_hotplug(struct drm_connector *connector,
+					     enum drm_connector_status status);
+int drm_atomic_helper_connector_hdmi_hotplug_edid(struct drm_connector *connector,
+						  enum drm_connector_status status,
+						  const struct drm_edid *drm_edid);
 
 enum drm_mode_status
 drm_hdmi_connector_mode_valid(struct drm_connector *connector,

-- 
2.39.5