[PATCH] gpu: drm: i915: display: Avoid null values intel_plane_atomic_check_with_state

[Alessandro Zanni <alessandro.zanni87@gmail.com>]

This fix solves multiple Smatch errors:

drivers/gpu/drm/i915/display/intel_atomic_plane.c:660
intel_plane_atomic_check_with_state() error:
we previously assumed 'fb' could be null (see line 648)

drivers/gpu/drm/i915/display/intel_atomic_plane.c:664
intel_plane_atomic_check_with_state()
error: we previously assumed 'fb' could be null (see line 659)

drivers/gpu/drm/i915/display/intel_atomic_plane.c:671
intel_plane_atomic_check_with_state()
error: we previously assumed 'fb' could be null (see line 663)

We should check first if fb is not null before to access its properties.

Signed-off-by: Alessandro Zanni <alessandro.zanni87@gmail.com>
---
 drivers/gpu/drm/i915/display/intel_atomic_plane.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
index e979786aa5cf..1606f79b39e6 100644
--- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
+++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
@@ -656,18 +656,18 @@ int intel_plane_atomic_check_with_state(const struct intel_crtc_state *old_crtc_
 	    intel_plane_is_scaled(new_plane_state))
 		new_crtc_state->scaled_planes |= BIT(plane->id);
 
-	if (new_plane_state->uapi.visible &&
+	if (new_plane_state->uapi.visible && fb &&
 	    intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier))
 		new_crtc_state->nv12_planes |= BIT(plane->id);
 
-	if (new_plane_state->uapi.visible &&
+	if (new_plane_state->uapi.visible && fb &&
 	    fb->format->format == DRM_FORMAT_C8)
 		new_crtc_state->c8_planes |= BIT(plane->id);
 
 	if (new_plane_state->uapi.visible || old_plane_state->uapi.visible)
 		new_crtc_state->update_planes |= BIT(plane->id);
 
-	if (new_plane_state->uapi.visible &&
+	if (new_plane_state->uapi.visible && fb &&
 	    intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier)) {
 		new_crtc_state->data_rate_y[plane->id] =
 			intel_plane_data_rate(new_crtc_state, new_plane_state, 0);
-- 
2.43.0