[PATCH 1/2] drm/msm/dpu1: don't choke on disabling the writeback connector

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

In order to prevent any errors on connector being disabled, move the
state->crtc check upfront. This should fix the issues during suspend
when the writeback connector gets forcebly disabled.

Fixes: 71174f362d67 ("drm/msm/dpu: move writeback's atomic_check to dpu_writeback.c")
Cc: stable@vger.kernel.org
Reported-by: Leonard Lausen <leonard@lausen.nl>
Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/57
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
index 16f144cbc0c9..5c172bcf3419 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
@@ -39,6 +39,13 @@ static int dpu_wb_conn_atomic_check(struct drm_connector *connector,
 
 	DPU_DEBUG("[atomic_check:%d]\n", connector->base.id);
 
+	crtc = conn_state->crtc;
+	if (!crtc)
+		return 0;
+
+	if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
+		return 0;
+
 	if (!conn_state || !conn_state->connector) {
 		DPU_ERROR("invalid connector state\n");
 		return -EINVAL;
@@ -47,13 +54,6 @@ static int dpu_wb_conn_atomic_check(struct drm_connector *connector,
 		return -EINVAL;
 	}
 
-	crtc = conn_state->crtc;
-	if (!crtc)
-		return 0;
-
-	if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
-		return 0;
-
 	crtc_state = drm_atomic_get_crtc_state(state, crtc);
 	if (IS_ERR(crtc_state))
 		return PTR_ERR(crtc_state);

-- 
2.39.2