[PATCH v9 2/5] drm/connector: Add support for privacy-screen property

[Rajat Jain]

Add support for generic electronic privacy screen property, that
can be added by systems that have an integrated EPS.

Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
---
v9: rebased on top of https://cgit.freedesktop.org/drm/drm-tip:drm-tip
v8: Remove the ...destroy_privacy_screen() method and let the property
    be destroyed along with others at the time of device destruction.
    (because drm core doesn't also like properties destroyed in
     late_register()).
v7: * Initial version, formed by moving the privacy-screen property into
      drm core.
    * Break the init_property() into create_property() and attach_property()
      so that property can be created while registering connector, but
      attached in late_register() (after ACPI node detection).


 drivers/gpu/drm/drm_atomic_uapi.c |  4 +++
 drivers/gpu/drm/drm_connector.c   | 51 +++++++++++++++++++++++++++++++
 include/drm/drm_connector.h       | 24 +++++++++++++++
 3 files changed, 79 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index a1e5e262bae2d..843a8cdacd149 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -766,6 +766,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
 						   fence_ptr);
 	} else if (property == connector->max_bpc_property) {
 		state->max_requested_bpc = val;
+	} else if (property == connector->privacy_screen_property) {
+		state->privacy_screen_status = val;
 	} else if (connector->funcs->atomic_set_property) {
 		return connector->funcs->atomic_set_property(connector,
 				state, property, val);
@@ -842,6 +844,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector,
 		*val = 0;
 	} else if (property == connector->max_bpc_property) {
 		*val = state->max_requested_bpc;
+	} else if (property == connector->privacy_screen_property) {
+		*val = state->privacy_screen_status;
 	} else if (connector->funcs->atomic_get_property) {
 		return connector->funcs->atomic_get_property(connector,
 				state, property, val);
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 644f0ad106717..182aa557962b2 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -1186,6 +1186,10 @@ static const struct drm_prop_enum_list dp_colorspaces[] = {
  *	can also expose this property to external outputs, in which case they
  *	must support "None", which should be the default (since external screens
  *	have a built-in scaler).
+ *
+ * privacy-screen:
+ *	This optional property can be used to enable / disable an integrated
+ *	electronic privacy screen that is available on some displays.
  */
 
 int drm_connector_create_standard_properties(struct drm_device *dev)
@@ -2152,6 +2156,53 @@ int drm_connector_set_panel_orientation_with_quirk(
 }
 EXPORT_SYMBOL(drm_connector_set_panel_orientation_with_quirk);
 
+static const struct drm_prop_enum_list privacy_screen_enum[] = {
+	{ PRIVACY_SCREEN_DISABLED, "Disabled" },
+	{ PRIVACY_SCREEN_ENABLED, "Enabled" },
+};
+
+/**
+ * drm_connector_create_privacy_screen_property -
+ *     create the drm connecter's privacy-screen property.
+ * @connector: connector for which to create the privacy-screen property
+ *
+ * This function creates the "privacy-screen" property for the
+ * connector. It is not attached.
+ */
+void
+drm_connector_create_privacy_screen_property(struct drm_connector *connector)
+{
+	if (connector->privacy_screen_property)
+		return;
+
+	connector->privacy_screen_property =
+		drm_property_create_enum(connector->dev, DRM_MODE_PROP_ENUM,
+					 "privacy-screen", privacy_screen_enum,
+					 ARRAY_SIZE(privacy_screen_enum));
+}
+EXPORT_SYMBOL(drm_connector_create_privacy_screen_property);
+
+/**
+ * drm_connector_attach_privacy_screen_property -
+ *     attach the drm connecter's privacy-screen property.
+ * @connector: connector on which to attach the privacy-screen property
+ *
+ * This function attaches the "privacy-screen" property to the
+ * connector. Initial state of privacy-screen is set to disabled.
+ */
+void
+drm_connector_attach_privacy_screen_property(struct drm_connector *connector)
+{
+	struct drm_property *prop = connector->privacy_screen_property;
+
+	if (!prop)
+		return;
+
+	drm_object_attach_property(&connector->base, prop,
+				   PRIVACY_SCREEN_DISABLED);
+}
+EXPORT_SYMBOL(drm_connector_attach_privacy_screen_property);
+
 int drm_connector_set_obj_prop(struct drm_mode_object *obj,
 				    struct drm_property *property,
 				    uint64_t value)
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 19ae6bb5c85be..f9ce89cc13542 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -271,6 +271,20 @@ struct drm_monitor_range_info {
 	u8 max_vfreq;
 };
 
+/**
+ * enum drm_privacy_screen_status - privacy screen status
+ *
+ * This enum is used to track and control the state of the integrated privacy
+ * screen present on some display panels, via the "privacy-screen" property.
+ *
+ * @PRIVACY_SCREEN_DISABLED: The privacy-screen on the panel is disabled
+ * @PRIVACY_SCREEN_ENABLED:  The privacy-screen on the panel is enabled
+ **/
+enum drm_privacy_screen_status {
+	PRIVACY_SCREEN_DISABLED = 0,
+	PRIVACY_SCREEN_ENABLED = 1,
+};
+
 /*
  * This is a consolidated colorimetry list supported by HDMI and
  * DP protocol standard. The respective connectors will register
@@ -686,6 +700,8 @@ struct drm_connector_state {
 	 */
 	u8 max_bpc;
 
+	enum drm_privacy_screen_status privacy_screen_status;
+
 	/**
 	 * @hdr_output_metadata:
 	 * DRM blob property for HDR output metadata
@@ -1285,6 +1301,12 @@ struct drm_connector {
 	 */
 	struct drm_property *max_bpc_property;
 
+	/**
+	 *  @privacy_screen_property: Optional property for the connector to
+	 *  control the integrated privacy screen, if available.
+	 */
+	struct drm_property *privacy_screen_property;
+
 #define DRM_CONNECTOR_POLL_HPD (1 << 0)
 #define DRM_CONNECTOR_POLL_CONNECT (1 << 1)
 #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2)
@@ -1598,6 +1620,8 @@ int drm_connector_set_panel_orientation_with_quirk(
 	int width, int height);
 int drm_connector_attach_max_bpc_property(struct drm_connector *connector,
 					  int min, int max);
+void drm_connector_create_privacy_screen_property(struct drm_connector *conn);
+void drm_connector_attach_privacy_screen_property(struct drm_connector *conn);
 
 /**
  * struct drm_tile_group - Tile group metadata
-- 
2.25.1.481.gfbce0eb801-goog