backend/drm: store drm prop lists as structs

This makes modifying the property lists slightly easier.

backend/drm/atomic.c

@@ -320,7 +320,7 @@ void drm_atomic_connector_rollback_commit(struct wlr_drm_connector_state *state)
 
 static void plane_disable(struct atomic *atom, struct wlr_drm_plane *plane) {
 	uint32_t id = plane->id;
-	const union wlr_drm_plane_props *props = &plane->props;
+	const struct wlr_drm_plane_props *props = &plane->props;
 	atomic_add(atom, id, props->fb_id, 0);
 	atomic_add(atom, id, props->crtc_id, 0);
 }
@@ -329,7 +329,7 @@ static void set_plane_props(struct atomic *atom, struct wlr_drm_backend *drm,
 		struct wlr_drm_plane *plane, struct wlr_drm_fb *fb, uint32_t crtc_id,
 		int32_t x, int32_t y) {
 	uint32_t id = plane->id;
-	const union wlr_drm_plane_props *props = &plane->props;
+	const struct wlr_drm_plane_props *props = &plane->props;
 
 	if (fb == NULL) {
 		wlr_log(WLR_ERROR, "Failed to acquire FB for plane %"PRIu32, plane->id);

backend/drm/drm.c

@@ -139,7 +139,7 @@ static bool init_plane(struct wlr_drm_backend *drm,
 		struct wlr_drm_plane *p, const drmModePlane *drm_plane) {
 	uint32_t id = drm_plane->plane_id;
 
-	union wlr_drm_plane_props props = {0};
+	struct wlr_drm_plane_props props = {0};
 	if (!get_drm_plane_props(drm->fd, id, &props)) {
 		return false;
 	}

backend/drm/properties.c

@@ -19,7 +19,7 @@ struct prop_info {
 };
 
 static const struct prop_info connector_info[] = {
-#define INDEX(name) (offsetof(union wlr_drm_connector_props, name) / sizeof(uint32_t))
+#define INDEX(name) (offsetof(struct wlr_drm_connector_props, name) / sizeof(uint32_t))
 	{ "CRTC_ID", INDEX(crtc_id) },
 	{ "DPMS", INDEX(dpms) },
 	{ "EDID", INDEX(edid) },
@@ -35,7 +35,7 @@ static const struct prop_info connector_info[] = {
 };
 
 static const struct prop_info crtc_info[] = {
-#define INDEX(name) (offsetof(union wlr_drm_crtc_props, name) / sizeof(uint32_t))
+#define INDEX(name) (offsetof(struct wlr_drm_crtc_props, name) / sizeof(uint32_t))
 	{ "ACTIVE", INDEX(active) },
 	{ "GAMMA_LUT", INDEX(gamma_lut) },
 	{ "GAMMA_LUT_SIZE", INDEX(gamma_lut_size) },
@@ -45,7 +45,7 @@ static const struct prop_info crtc_info[] = {
 };
 
 static const struct prop_info plane_info[] = {
-#define INDEX(name) (offsetof(union wlr_drm_plane_props, name) / sizeof(uint32_t))
+#define INDEX(name) (offsetof(struct wlr_drm_plane_props, name) / sizeof(uint32_t))
 	{ "CRTC_H", INDEX(crtc_h) },
 	{ "CRTC_ID", INDEX(crtc_id) },
 	{ "CRTC_W", INDEX(crtc_w) },
@@ -100,19 +100,18 @@ static bool scan_properties(int fd, uint32_t id, uint32_t type, uint32_t *result
 	return true;
 }
 
-bool get_drm_connector_props(int fd, uint32_t id,
+bool get_drm_connector_props(int fd, uint32_t id, struct wlr_drm_connector_props *out) {
-		union wlr_drm_connector_props *out) {
+	return scan_properties(fd, id, DRM_MODE_OBJECT_CONNECTOR, (uint32_t *)out,
-	return scan_properties(fd, id, DRM_MODE_OBJECT_CONNECTOR, out->props,
 		connector_info, sizeof(connector_info) / sizeof(connector_info[0]));
 }
 
-bool get_drm_crtc_props(int fd, uint32_t id, union wlr_drm_crtc_props *out) {
+bool get_drm_crtc_props(int fd, uint32_t id, struct wlr_drm_crtc_props *out) {
-	return scan_properties(fd, id, DRM_MODE_OBJECT_CRTC, out->props,
+	return scan_properties(fd, id, DRM_MODE_OBJECT_CRTC, (uint32_t *)out,
 		crtc_info, sizeof(crtc_info) / sizeof(crtc_info[0]));
 }
 
-bool get_drm_plane_props(int fd, uint32_t id, union wlr_drm_plane_props *out) {
+bool get_drm_plane_props(int fd, uint32_t id, struct wlr_drm_plane_props *out) {
-	return scan_properties(fd, id, DRM_MODE_OBJECT_PLANE, out->props,
+	return scan_properties(fd, id, DRM_MODE_OBJECT_PLANE, (uint32_t *)out,
 		plane_info, sizeof(plane_info) / sizeof(plane_info[0]));
 }
 

include/backend/drm/drm.h

@@ -29,7 +29,7 @@ struct wlr_drm_plane {
 
 	struct wlr_drm_format_set formats;
 
-	union wlr_drm_plane_props props;
+	struct wlr_drm_plane_props props;
 
 	uint32_t initial_crtc_id;
 	struct liftoff_plane *liftoff;
@@ -71,7 +71,7 @@ struct wlr_drm_crtc {
 	struct wlr_drm_plane *primary;
 	struct wlr_drm_plane *cursor;
 
-	union wlr_drm_crtc_props props;
+	struct wlr_drm_crtc_props props;
 };
 
 struct wlr_drm_backend {
@@ -181,7 +181,7 @@ struct wlr_drm_connector {
 	struct wlr_drm_crtc *crtc;
 	uint32_t possible_crtcs;
 
-	union wlr_drm_connector_props props;
+	struct wlr_drm_connector_props props;
 
 	bool cursor_enabled;
 	int cursor_x, cursor_y;

include/backend/drm/properties.h

@@ -11,8 +11,7 @@
  * https://dri.freedesktop.org/docs/drm/gpu/drm-kms.html#kms-properties
  */
 
-union wlr_drm_connector_props {
+struct wlr_drm_connector_props {
-	struct {
 	uint32_t edid;
 	uint32_t dpms;
 	uint32_t link_status; // not guaranteed to exist
@@ -27,12 +26,9 @@ union wlr_drm_connector_props {
 	// atomic-modesetting only
 
 	uint32_t crtc_id;
-	};
-	uint32_t props[4];
 };
 
-union wlr_drm_crtc_props {
+struct wlr_drm_crtc_props {
-	struct {
 	// Neither of these are guaranteed to exist
 	uint32_t vrr_enabled;
 	uint32_t gamma_lut;
@@ -42,12 +38,9 @@ union wlr_drm_crtc_props {
 
 	uint32_t active;
 	uint32_t mode_id;
-	};
-	uint32_t props[6];
 };
 
-union wlr_drm_plane_props {
+struct wlr_drm_plane_props {
-	struct {
 	uint32_t type;
 	uint32_t rotation; // Not guaranteed to exist
 	uint32_t in_formats; // Not guaranteed to exist
@@ -67,14 +60,12 @@ union wlr_drm_plane_props {
 	uint32_t fb_damage_clips;
 	uint32_t hotspot_x;
 	uint32_t hotspot_y;
-	};
-	uint32_t props[16];
 };
 
 bool get_drm_connector_props(int fd, uint32_t id,
-	union wlr_drm_connector_props *out);
+	struct wlr_drm_connector_props *out);
-bool get_drm_crtc_props(int fd, uint32_t id, union wlr_drm_crtc_props *out);
+bool get_drm_crtc_props(int fd, uint32_t id, struct wlr_drm_crtc_props *out);
-bool get_drm_plane_props(int fd, uint32_t id, union wlr_drm_plane_props *out);
+bool get_drm_plane_props(int fd, uint32_t id, struct wlr_drm_plane_props *out);
 
 bool get_drm_prop(int fd, uint32_t obj, uint32_t prop, uint64_t *ret);
 void *get_drm_prop_blob(int fd, uint32_t obj, uint32_t prop, size_t *ret_len);