diff --git a/glamor/glamor_egl.c b/glamor/glamor_egl.c
index 918a790de..844dbbe71 100644
--- a/glamor/glamor_egl.c
+++ b/glamor/glamor_egl.c
@@ -562,6 +562,8 @@ static uint32_t
 gbm_format_for_depth(CARD8 depth)
 {
     switch (depth) {
+    case 15:
+        return GBM_FORMAT_ARGB1555;
     case 16:
         return GBM_FORMAT_RGB565;
     case 24:
diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
index 570fbc54a..2a9f3c164 100644
--- a/hw/xwayland/xwayland-glamor-gbm.c
+++ b/hw/xwayland/xwayland-glamor-gbm.c
@@ -116,6 +116,8 @@ static uint32_t
 gbm_format_for_depth(int depth, int gles)
 {
     switch (depth) {
+    case 15:
+        return GBM_FORMAT_ARGB1555;
     case 16:
         return GBM_FORMAT_RGB565;
     case 24: