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From 64b22a0da12adb571c01edd671ee43634ebd7e41 Mon Sep 17 00:00:00 2001
From: Abhinav Kumar <quic_abhinavk@quicinc.com>
Date: Wed, 18 May 2022 15:34:07 -0700
Subject: [PATCH] drm/msm/dpu: handle pm_runtime_get_sync() errors in bind path
Git-commit: 64b22a0da12adb571c01edd671ee43634ebd7e41
Patch-mainline: v5.19-rc1
References: git-fixes

If there are errors while trying to enable the pm in the
bind path, it will lead to unclocked access of hw revision
register thereby crashing the device.

This will not address why the pm_runtime_get_sync() fails
but at the very least we should be able to prevent the
crash by handling the error and bailing out earlier.

changes in v2:
	- use pm_runtime_resume_and_get() instead of
	  pm_runtime_get_sync()

Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/486721/
Link: https://lore.kernel.org/r/20220518223407.26147-1-quic_abhinavk@quicinc.com
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index 2b9d931474e0..bce47647d891 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -1089,7 +1089,9 @@ static int dpu_kms_hw_init(struct msm_kms *kms)
 
 	dpu_kms_parse_data_bus_icc_path(dpu_kms);
 
-	pm_runtime_get_sync(&dpu_kms->pdev->dev);
+	rc = pm_runtime_resume_and_get(&dpu_kms->pdev->dev);
+	if (rc < 0)
+		goto error;
 
 	dpu_kms->core_rev = readl_relaxed(dpu_kms->mmio + 0x0);
 
-- 
2.35.3