linux-kernel - [PATCH v4 2/3] drm/msm: reset devfreq freq_table/max_state before devfreq_add

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Date:   Mon, 13 Jul 2020 18:53:41 -0400
From:   Jonathan Marek <jonathan@...ek.ca>
To:     freedreno@...ts.freedesktop.org
Cc:     Rob Clark <robdclark@...il.com>, Sean Paul <sean@...rly.run>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        linux-arm-msm@...r.kernel.org (open list:DRM DRIVER FOR MSM ADRENO GPU),
        dri-devel@...ts.freedesktop.org (open list:DRM DRIVER FOR MSM ADRENO
        GPU), linux-kernel@...r.kernel.org (open list)
Subject: [PATCH v4 2/3] drm/msm: reset devfreq freq_table/max_state before devfreq_add_device

These never get set back to 0 when probing fails, so an attempt to probe
again results in broken behavior. Fix the problem by setting thse to zero
before they are used.

Signed-off-by: Jonathan Marek <jonathan@...ek.ca>
---
 drivers/gpu/drm/msm/msm_gpu.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index a22d30622306..aa9775ab52f0 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -93,7 +93,11 @@ static void msm_devfreq_init(struct msm_gpu *gpu)
 	/*
 	 * Don't set the freq_table or max_state and let devfreq build the table
 	 * from OPP
+	 * After a deferred probe, these may have be left to non-zero values,
+	 * so set them back to zero before creating the devfreq device
 	 */
+	msm_devfreq_profile.freq_table = NULL;
+	msm_devfreq_profile.max_state = 0;
 
 	gpu->devfreq.devfreq = devm_devfreq_add_device(&gpu->pdev->dev,
 			&msm_devfreq_profile, DEVFREQ_GOV_SIMPLE_ONDEMAND,
-- 
2.26.1