[PATCH -next 2/2] drm/rockchip: fix PM usage counter unbalance in poweron

Zhang Qilong zhangqilong3 at huawei.com
Thu Sep 22 06:21:07 PDT 2022


pm_runtime_get_sync will increment pm usage counter even it failed.
Forgetting to putting operation will result in reference leak here.
We fix it by replacing it with the newest pm_runtime_resume_and_get
to keep usage counter balanced.

Fixes:34cc0aa254560 ("drm/rockchip: Add support for Rockchip Soc LVDS")
Fixes:cca1705c3d895 ("drm/rockchip: lvds: Add PX30 support")
Signed-off-by: Zhang Qilong <zhangqilong3 at huawei.com>
---
 drivers/gpu/drm/rockchip/rockchip_lvds.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_lvds.c b/drivers/gpu/drm/rockchip/rockchip_lvds.c
index 5a284332ec49..68f6ebb33460 100644
--- a/drivers/gpu/drm/rockchip/rockchip_lvds.c
+++ b/drivers/gpu/drm/rockchip/rockchip_lvds.c
@@ -152,7 +152,7 @@ static int rk3288_lvds_poweron(struct rockchip_lvds *lvds)
 		DRM_DEV_ERROR(lvds->dev, "failed to enable lvds pclk %d\n", ret);
 		return ret;
 	}
-	ret = pm_runtime_get_sync(lvds->dev);
+	ret = pm_runtime_resume_and_get(lvds->dev);
 	if (ret < 0) {
 		DRM_DEV_ERROR(lvds->dev, "failed to get pm runtime: %d\n", ret);
 		clk_disable(lvds->pclk);
@@ -336,16 +336,20 @@ static int px30_lvds_poweron(struct rockchip_lvds *lvds)
 {
 	int ret;
 
-	ret = pm_runtime_get_sync(lvds->dev);
+	ret = pm_runtime_resume_and_get(lvds->dev);
 	if (ret < 0) {
 		DRM_DEV_ERROR(lvds->dev, "failed to get pm runtime: %d\n", ret);
 		return ret;
 	}
 
 	/* Enable LVDS mode */
-	return regmap_update_bits(lvds->grf, PX30_LVDS_GRF_PD_VO_CON1,
+	ret = regmap_update_bits(lvds->grf, PX30_LVDS_GRF_PD_VO_CON1,
 				  PX30_LVDS_MODE_EN(1) | PX30_LVDS_P2S_EN(1),
 				  PX30_LVDS_MODE_EN(1) | PX30_LVDS_P2S_EN(1));
+	if (ret)
+		pm_runtime_put(lvds->dev);
+
+	return ret;
 }
 
 static void px30_lvds_poweroff(struct rockchip_lvds *lvds)
-- 
2.25.1




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