[PATCH hwc] drm_hwcomposer: correct handling of DRM_MODE_ROTATE_0

[Rob Herring]

If the rotation property is supported for a plane, then the rotation
value must be non-zero. For the case of 0 degree rotation,
DRM_MODE_ROTATE_0 needs to be set.

Signed-off-by: Rob Herring <robh at kernel.org>
---
 drmdisplaycompositor.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drmdisplaycompositor.cpp b/drmdisplaycompositor.cpp
index 8225726df5cd..dceb78d452c4 100644
--- a/drmdisplaycompositor.cpp
+++ b/drmdisplaycompositor.cpp
@@ -581,6 +581,8 @@ int DrmDisplayCompositor::CommitFrame(DrmDisplayComposition *display_comp,
         rotation |= DRM_MODE_ROTATE_180;
       else if (layer.transform & DrmHwcTransform::kRotate270)
         rotation |= DRM_MODE_ROTATE_270;
+      else
+        rotation |= DRM_MODE_ROTATE_0;
 
       if (fence_fd < 0) {
         int prop_id = plane->in_fence_fd_property().id();
@@ -610,7 +612,7 @@ int DrmDisplayCompositor::CommitFrame(DrmDisplayComposition *display_comp,
     }
 
     // TODO: Once we have atomic test, this should fall back to GL
-    if (rotation && plane->rotation_property().id() == 0) {
+    if (rotation != DRM_MODE_ROTATE_0 && plane->rotation_property().id() == 0) {
       ALOGE("Rotation is not supported on plane %d", plane->id());
       ret = -EINVAL;
       break;
-- 
2.14.1