1 files changed, 4 insertions, 1 deletions
diff --git a/hwc/hwc.c b/hwc/hwc.c
index 6b69e4b..c4da67d 100644
--- a/hwc/hwc.c
+++ b/hwc/hwc.c
@@ -811,7 +811,10 @@ static int omap4_hwc_set(struct hwc_composer_device *dev, hwc_display_t dpy,
 
     // LOGD("set %d layers (sgx=%d)\n", dsscomp->num_ovls, hwc_dev->use_sgx);
 
-    if (hwc_dev->use_sgx) {
+    if (hwc_dev->use_sgx && dpy && sur) {
+        // list can be NULL which means hwc is temporarily disabled.
+        // however, if dpy and sur are null it means we're turning the
+        // screen off. no shall not call eglSwapBuffers() in that case.
         if (!eglSwapBuffers((EGLDisplay)dpy, (EGLSurface)sur)) {
             LOGE("eglSwapBuffers error");
             err = HWC_EGL_ERROR;