[PATCH 02/15] drm/atomic: Reject attempts to use multiple rotation angles at once

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

The rotation property should only accept exactly one rotation angle
at once. Let's reject attempts to set none or multiple angles.

Testcase: igt/kms_rotation_crc/bad-rotation
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/drm_atomic.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 23739609427d..58b90c247153 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -710,6 +710,8 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 	} else if (property == config->prop_src_h) {
 		state->src_h = val;
 	} else if (property == config->rotation_property) {
+		if (!is_power_of_2(val & DRM_ROTATE_MASK))
+			return -EINVAL;
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
-- 
2.7.4