drm: Add a rotation parameter to connectors.

Some connectors, particularly writeback, can implement flip
or transpose operations as writing back to memory.

Add a connector rotation property to control this.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

Author: 6by9

drivers/gpu/drm/drm_atomic_uapi.c

@@ -793,6 +793,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
 		state->privacy_screen_sw_state = val;
 	} else if (property == connector->broadcast_rgb_property) {
 		state->hdmi.broadcast_rgb = val;
+	} else if (property == connector->rotation_property) {
+		state->rotation = val;
 	} else if (connector->funcs->atomic_set_property) {
 		return connector->funcs->atomic_set_property(connector,
 				state, property, val);
@@ -884,6 +886,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector,
 		*val = state->privacy_screen_sw_state;
 	} else if (property == connector->broadcast_rgb_property) {
 		*val = state->hdmi.broadcast_rgb;
+	} else if (property == connector->rotation_property) {
+		*val = state->rotation;
 	} else if (connector->funcs->atomic_get_property) {
 		return connector->funcs->atomic_get_property(connector,
 				state, property, val);

drivers/gpu/drm/drm_blend.c

@@ -241,6 +241,16 @@ int drm_plane_create_alpha_property(struct drm_plane *plane)
 }
 EXPORT_SYMBOL(drm_plane_create_alpha_property);
 
+static const struct drm_prop_enum_list drm_rotate_props[] = {
+	{ __builtin_ffs(DRM_MODE_ROTATE_0) - 1,   "rotate-0" },
+	{ __builtin_ffs(DRM_MODE_ROTATE_90) - 1,  "rotate-90" },
+	{ __builtin_ffs(DRM_MODE_ROTATE_180) - 1, "rotate-180" },
+	{ __builtin_ffs(DRM_MODE_ROTATE_270) - 1, "rotate-270" },
+	{ __builtin_ffs(DRM_MODE_REFLECT_X) - 1,  "reflect-x" },
+	{ __builtin_ffs(DRM_MODE_REFLECT_Y) - 1,  "reflect-y" },
+	{ __builtin_ffs(DRM_MODE_TRANSPOSE) - 1,  "transpose" },
+};
+
 /**
  * drm_plane_create_rotation_property - create a new rotation property
  * @plane: drm plane
@@ -281,23 +291,15 @@ int drm_plane_create_rotation_property(struct drm_plane *plane,
 				       unsigned int rotation,
 				       unsigned int supported_rotations)
 {
-	static const struct drm_prop_enum_list props[] = {
-		{ __builtin_ffs(DRM_MODE_ROTATE_0) - 1,   "rotate-0" },
-		{ __builtin_ffs(DRM_MODE_ROTATE_90) - 1,  "rotate-90" },
-		{ __builtin_ffs(DRM_MODE_ROTATE_180) - 1, "rotate-180" },
-		{ __builtin_ffs(DRM_MODE_ROTATE_270) - 1, "rotate-270" },
-		{ __builtin_ffs(DRM_MODE_REFLECT_X) - 1,  "reflect-x" },
-		{ __builtin_ffs(DRM_MODE_REFLECT_Y) - 1,  "reflect-y" },
-		{ __builtin_ffs(DRM_MODE_TRANSPOSE) - 1,  "transpose" },
-	};
 	struct drm_property *prop;
 
 	WARN_ON((supported_rotations & DRM_MODE_ROTATE_MASK) == 0);
 	WARN_ON(!is_power_of_2(rotation & DRM_MODE_ROTATE_MASK));
 	WARN_ON(rotation & ~supported_rotations);
 
 	prop = drm_property_create_bitmask(plane->dev, 0, "rotation",
-					   props, ARRAY_SIZE(props),
+					   drm_rotate_props,
+					   ARRAY_SIZE(drm_rotate_props),
 					   supported_rotations);
 	if (!prop)
 		return -ENOMEM;
@@ -313,6 +315,34 @@ int drm_plane_create_rotation_property(struct drm_plane *plane,
 }
 EXPORT_SYMBOL(drm_plane_create_rotation_property);
 
+int drm_connector_create_rotation_property(struct drm_connector *conn,
+					   unsigned int rotation,
+					   unsigned int supported_rotations)
+{
+	struct drm_property *prop;
+
+	WARN_ON((supported_rotations & DRM_MODE_ROTATE_MASK) == 0);
+	WARN_ON(!is_power_of_2(rotation & DRM_MODE_ROTATE_MASK));
+	WARN_ON(rotation & ~supported_rotations);
+
+	prop = drm_property_create_bitmask(conn->dev, 0, "rotation",
+					   drm_rotate_props,
+					   ARRAY_SIZE(drm_rotate_props),
+					   supported_rotations);
+	if (!prop)
+		return -ENOMEM;
+
+	drm_object_attach_property(&conn->base, prop, rotation);
+
+	if (conn->state)
+		conn->state->rotation = rotation;
+
+	conn->rotation_property = prop;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_connector_create_rotation_property);
+
 /**
  * drm_rotation_simplify() - Try to simplify the rotation
  * @rotation: Rotation to be simplified

include/drm/drm_blend.h

@@ -34,6 +34,7 @@
 struct drm_device;
 struct drm_atomic_state;
 struct drm_plane;
+struct drm_connector;
 
 static inline bool drm_rotation_90_or_270(unsigned int rotation)
 {
@@ -58,4 +59,8 @@ int drm_atomic_normalize_zpos(struct drm_device *dev,
 			      struct drm_atomic_state *state);
 int drm_plane_create_blend_mode_property(struct drm_plane *plane,
 					 unsigned int supported_modes);
+
+int drm_connector_create_rotation_property(struct drm_connector *conn,
+					   unsigned int rotation,
+					   unsigned int supported_rotations);
 #endif

include/drm/drm_connector.h

@@ -1149,6 +1149,11 @@ struct drm_connector_state {
 	 * @drm_atomic_helper_connector_hdmi_check().
 	 */
 	struct drm_connector_hdmi_state hdmi;
+
+	/**
+	 * @rotation: Connector property to rotate the maximum output image.
+	 */
+	u32 rotation;
 };
 
 struct drm_connector_hdmi_audio_funcs {
@@ -2103,6 +2108,12 @@ struct drm_connector {
 	 */
 	struct drm_property *broadcast_rgb_property;
 
+	/**
+	 * @rotation_property: Optional DRM property controlling rotation of the
+	 * output.
+	 */
+	struct drm_property *rotation_property;
+
 #define DRM_CONNECTOR_POLL_HPD (1 << 0)
 #define DRM_CONNECTOR_POLL_CONNECT (1 << 1)
 #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2)