Merge pull request #1277 from emersion/reset-gamma

backend/drm: reset gamma table on VT switch

1 files changed, 35 insertions, 15 deletions

diff --git a/backend/drm/drm.c b/backend/drm/drm.c
index 110c2229..fa9a95ae 100644
--- a/backend/drm/drm.c
+++ b/backend/drm/drm.c
@@ -193,6 +193,7 @@ void finish_drm_resources(struct wlr_drm_backend *drm) {
 		if (crtc->gamma_lut) {
 			drmModeDestroyPropertyBlob(drm->fd, crtc->gamma_lut);
 		}
+		free(crtc->gamma_table);
 	}
 	for (size_t i = 0; i < drm->num_planes; ++i) {
 		struct wlr_drm_plane *plane = &drm->planes[i];
@@ -251,7 +252,7 @@ static bool drm_connector_swap_buffers(struct wlr_output *output,
 	return true;
 }
 
-static void fill_empty_gamma_table(uint32_t size,
+static void fill_empty_gamma_table(size_t size,
 		uint16_t *r, uint16_t *g, uint16_t *b) {
 	for (uint32_t i = 0; i < size; ++i) {
 		uint16_t val = (uint32_t)0xffff * i / (size - 1);
@@ -259,7 +260,7 @@ static void fill_empty_gamma_table(uint32_t size,
 	}
 }
 
-static uint32_t drm_connector_get_gamma_size(struct wlr_output *output) {
+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);
 
@@ -270,8 +271,8 @@ static uint32_t drm_connector_get_gamma_size(struct wlr_output *output) {
 	return 0;
 }
 
-static bool drm_connector_set_gamma(struct wlr_output *output,
-		uint32_t size, uint16_t *r, uint16_t *g, uint16_t *b) {
+bool set_drm_connector_gamma(struct wlr_output *output, size_t size,
+		const uint16_t *r, const uint16_t *g, const uint16_t *b) {
 	struct wlr_drm_connector *conn = get_drm_connector_from_output(output);
 	struct wlr_drm_backend *drm = get_drm_backend_from_backend(output->backend);
 
@@ -279,25 +280,42 @@ static bool drm_connector_set_gamma(struct wlr_output *output,
 		return false;
 	}
 
-	uint16_t *reset_table = NULL;
+	bool reset = false;
 	if (size == 0) {
+		reset = true;
 		size = drm_connector_get_gamma_size(output);
-		reset_table = malloc(3 * size * sizeof(uint16_t));
-		if (reset_table == NULL) {
-			wlr_log(WLR_ERROR, "Failed to allocate gamma table");
+		if (size == 0) {
 			return false;
 		}
-		r = reset_table;
-		g = reset_table + size;
-		b = reset_table + 2 * size;
-		fill_empty_gamma_table(size, r, g, b);
 	}
 
-	bool ok = drm->iface->crtc_set_gamma(drm, conn->crtc, r, g, b, size);
+	uint16_t *gamma_table = malloc(3 * size * sizeof(uint16_t));
+	if (gamma_table == NULL) {
+		wlr_log(WLR_ERROR, "Failed to allocate gamma table");
+		return false;
+	}
+	uint16_t *_r = gamma_table;
+	uint16_t *_g = gamma_table + size;
+	uint16_t *_b = gamma_table + 2 * size;
+
+	if (reset) {
+		fill_empty_gamma_table(size, _r, _g, _b);
+	} else {
+		memcpy(_r, r, size * sizeof(uint16_t));
+		memcpy(_g, g, size * sizeof(uint16_t));
+		memcpy(_b, b, size * sizeof(uint16_t));
+	}
+
+	bool ok = drm->iface->crtc_set_gamma(drm, conn->crtc, size, _r, _g, _b);
 	if (ok) {
 		wlr_output_update_needs_swap(output);
+
+		free(conn->crtc->gamma_table);
+		conn->crtc->gamma_table = gamma_table;
+		conn->crtc->gamma_table_size = size;
+	} else {
+		free(gamma_table);
 	}
-	free(reset_table);
 	return ok;
 }
 
@@ -724,7 +742,7 @@ static const struct wlr_output_impl output_impl = {
 	.destroy = drm_connector_destroy,
 	.make_current = drm_connector_make_current,
 	.swap_buffers = drm_connector_swap_buffers,
-	.set_gamma = drm_connector_set_gamma,
+	.set_gamma = set_drm_connector_gamma,
 	.get_gamma_size = drm_connector_get_gamma_size,
 	.export_dmabuf = drm_connector_export_dmabuf,
 };
@@ -759,6 +777,8 @@ static void dealloc_crtc(struct wlr_drm_connector *conn) {
 	wlr_log(WLR_DEBUG, "De-allocating CRTC %zu for output '%s'",
 		conn->crtc - drm->crtcs, conn->output.name);
 
+	set_drm_connector_gamma(&conn->output, 0, NULL, NULL, NULL);
+
 	for (size_t type = 0; type < 3; ++type) {
 		struct wlr_drm_plane *plane = conn->crtc->planes[type];
 		if (plane == NULL) {