[PATCH v3 14/27] drm/msm/dpu: don't use unsupported blend stages

[Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>]

The dpu_crtc_atomic_check() compares blending stage with DPU_STAGE_MAX
(maximum amount of blending stages supported by the driver), however we
should compare it against .max_mixer_blendstages, the maximum blend
stage supported by the mixer.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index c1579d6f5060..b485234eefb2 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -1129,6 +1129,7 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
 									  crtc);
 	struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
 	struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc_state);
+	struct dpu_kms *dpu_kms = _dpu_crtc_get_kms(crtc);
 
 	const struct drm_plane_state *pstate;
 	struct drm_plane *plane;
@@ -1164,7 +1165,7 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
 	drm_atomic_crtc_state_for_each_plane_state(plane, pstate, crtc_state) {
 		struct dpu_plane_state *dpu_pstate = to_dpu_plane_state(pstate);
 		struct drm_rect dst, clip = crtc_rect;
-		int z_pos;
+		int stage;
 
 		if (IS_ERR_OR_NULL(pstate)) {
 			rc = PTR_ERR(pstate);
@@ -1189,17 +1190,16 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
 			return -E2BIG;
 		}
 
-		z_pos = pstate->normalized_zpos;
-
-		/* verify z_pos setting before using it */
-		if (z_pos >= DPU_STAGE_MAX - DPU_STAGE_0) {
+		/* verify stage setting before using it */
+		stage = DPU_STAGE_0 + pstate->normalized_zpos;
+		if (stage >= dpu_kms->catalog->caps->max_mixer_blendstages) {
 			DPU_ERROR("> %d plane stages assigned\n",
-					DPU_STAGE_MAX - DPU_STAGE_0);
+					dpu_kms->catalog->caps->max_mixer_blendstages - DPU_STAGE_0);
 			return -EINVAL;
 		}
 
-		to_dpu_plane_state(pstate)->stage = z_pos + DPU_STAGE_0;
-		DRM_DEBUG_ATOMIC("%s: zpos %d\n", dpu_crtc->name, z_pos);
+		to_dpu_plane_state(pstate)->stage = stage;
+		DRM_DEBUG_ATOMIC("%s: stage %d\n", dpu_crtc->name, stage);
 
 	}
 
-- 
2.39.1