backend/drm: GAMMA_LUT_SIZE isn't atomic

GAMMA_LUT_SIZE isn't an atomic property. It can be used with the legacy
interface too. So we can unify both codepaths and remove
wlr_drm_interface.crtc_get_gamma_size.

It's no guaranteed to exist though, so we still need to keep the
fallback.

3 files changed, 15 insertions, 26 deletions

diff --git a/backend/drm/atomic.c b/backend/drm/atomic.c
index d4f033f0..3060d671 100644
--- a/backend/drm/atomic.c
+++ b/backend/drm/atomic.c
@@ -240,23 +240,6 @@ static bool atomic_crtc_commit(struct wlr_drm_backend *drm,
 	return true;
 }
 
-static size_t atomic_crtc_get_gamma_size(struct wlr_drm_backend *drm,
-		struct wlr_drm_crtc *crtc) {
-	if (crtc->props.gamma_lut_size == 0) {
-		return legacy_iface.crtc_get_gamma_size(drm, crtc);
-	}
-
-	uint64_t gamma_lut_size;
-	if (!get_drm_prop(drm->fd, crtc->id, crtc->props.gamma_lut_size,
-			&gamma_lut_size)) {
-		wlr_log(WLR_ERROR, "Unable to get gamma lut size");
-		return 0;
-	}
-
-	return (size_t)gamma_lut_size;
-}
-
 const struct wlr_drm_interface atomic_iface = {
 	.crtc_commit = atomic_crtc_commit,
-	.crtc_get_gamma_size = atomic_crtc_get_gamma_size,
 };
diff --git a/backend/drm/drm.c b/backend/drm/drm.c
index 60df4348..8482b368 100644
--- a/backend/drm/drm.c
+++ b/backend/drm/drm.c
@@ -581,12 +581,24 @@ static void fill_empty_gamma_table(size_t size,
 static size_t drm_connector_get_gamma_size(struct wlr_output *output) {
 	struct wlr_drm_connector *conn = get_drm_connector_from_output(output);
 	struct wlr_drm_backend *drm = get_drm_backend_from_backend(output->backend);
+	struct wlr_drm_crtc *crtc = conn->crtc;
 
-	if (conn->crtc) {
-		return drm->iface->crtc_get_gamma_size(drm, conn->crtc);
+	if (crtc == NULL) {
+		return 0;
 	}
 
-	return 0;
+	if (crtc->props.gamma_lut_size == 0) {
+		return (size_t)crtc->legacy_crtc->gamma_size;
+	}
+
+	uint64_t gamma_lut_size;
+	if (!get_drm_prop(drm->fd, crtc->id, crtc->props.gamma_lut_size,
+			&gamma_lut_size)) {
+		wlr_log(WLR_ERROR, "Unable to get gamma lut size");
+		return 0;
+	}
+
+	return gamma_lut_size;
 }
 
 bool set_drm_connector_gamma(struct wlr_output *output, size_t size,
diff --git a/backend/drm/legacy.c b/backend/drm/legacy.c
index 09e7df16..c32d0399 100644
--- a/backend/drm/legacy.c
+++ b/backend/drm/legacy.c
@@ -117,12 +117,6 @@ bool drm_legacy_crtc_set_gamma(struct wlr_drm_backend *drm,
 	return true;
 }
 
-static size_t legacy_crtc_get_gamma_size(struct wlr_drm_backend *drm,
-		struct wlr_drm_crtc *crtc) {
-	return (size_t)crtc->legacy_crtc->gamma_size;
-}
-
 const struct wlr_drm_interface legacy_iface = {
 	.crtc_commit = legacy_crtc_commit,
-	.crtc_get_gamma_size = legacy_crtc_get_gamma_size,
 };