[PATCH 6.0 0259/1073] drm/rockchip: lvds: fix PM usage counter unbalance in poweron

Greg Kroah-Hartman
2022-12-28T15:27:38Z

From: Zhang Qilong <zhangqilong3@huawei.com>

[ Upstream commit 4dba27f1a14592ac4cf71c3bc1cc1fd05dea8015 ]

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: 34cc0aa25456 ("drm/rockchip: Add support for Rockchip Soc LVDS")
Fixes: cca1705c3d89 ("drm/rockchip: lvds: Add PX30 support")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220922132107.105419-3-zhangqilong3@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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)
--
2.35.1