drm/atomic: Add TV subconnector property to get/set_property

The subconnector property was created by drm_mode_create_tv_properties(),
but wasn't exposed to the userspace through the generic
atomic_get/set_property implementation, and wasn't stored in any generic
state structure.

Let's solve this.
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://lore.kernel.org/r/20220728-rpi-analog-tv-properties-v4-6-60d38873f782@cerno.techSigned-off-by: Maxime Ripard <maxime@cerno.tech>

drivers/gpu/drm/drm_atomic_uapi.c

@@ -688,6 +688,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
 		return -EINVAL;
 	} else if (property == config->tv_select_subconnector_property) {
 		state->tv.select_subconnector = val;
+	} else if (property == config->tv_subconnector_property) {
+		state->tv.subconnector = val;
 	} else if (property == config->tv_left_margin_property) {
 		state->tv.margins.left = val;
 	} else if (property == config->tv_right_margin_property) {
@@ -796,6 +798,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector,
 			*val = connector->dpms;
 	} else if (property == config->tv_select_subconnector_property) {
 		*val = state->tv.select_subconnector;
+	} else if (property == config->tv_subconnector_property) {
+		*val = state->tv.subconnector;
 	} else if (property == config->tv_left_margin_property) {
 		*val = state->tv.margins.left;
 	} else if (property == config->tv_right_margin_property) {

include/drm/drm_connector.h

@@ -693,6 +693,7 @@ struct drm_connector_tv_margins {
 /**
  * struct drm_tv_connector_state - TV connector related states
  * @select_subconnector: selected subconnector
+ * @subconnector: detected subconnector
  * @margins: TV margins
  * @mode: TV mode
  * @brightness: brightness in percent
@@ -704,6 +705,7 @@ struct drm_connector_tv_margins {
  */
 struct drm_tv_connector_state {
 	enum drm_mode_subconnector select_subconnector;
+	enum drm_mode_subconnector subconnector;
 	struct drm_connector_tv_margins margins;
 	unsigned int mode;
 	unsigned int brightness;