[PATCH -next 2/3] dmaengine: stm32-dmamux: Fix PM usage counter unbalance in stm32 dmamux ops

Zhang Qilong zhangqilong3 at huawei.com
Sun Jun 6 23:46:39 PDT 2021


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 pm_runtime_resume_and_get to keep usage counter
balanced.

Fixes: 4f3ceca254e0f ("dmaengine: stm32-dmamux: Add PM Runtime support")
Signed-off-by: Zhang Qilong <zhangqilong3 at huawei.com>
---
 drivers/dma/stm32-dmamux.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c
index ef0d0555103d..a42164389ebc 100644
--- a/drivers/dma/stm32-dmamux.c
+++ b/drivers/dma/stm32-dmamux.c
@@ -137,7 +137,7 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec,
 
 	/* Set dma request */
 	spin_lock_irqsave(&dmamux->lock, flags);
-	ret = pm_runtime_get_sync(&pdev->dev);
+	ret = pm_runtime_resume_and_get(&pdev->dev);
 	if (ret < 0) {
 		spin_unlock_irqrestore(&dmamux->lock, flags);
 		goto error;
@@ -336,7 +336,7 @@ static int stm32_dmamux_suspend(struct device *dev)
 	struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev);
 	int i, ret;
 
-	ret = pm_runtime_get_sync(dev);
+	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0)
 		return ret;
 
@@ -361,7 +361,7 @@ static int stm32_dmamux_resume(struct device *dev)
 	if (ret < 0)
 		return ret;
 
-	ret = pm_runtime_get_sync(dev);
+	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0)
 		return ret;
 
-- 
2.31.1




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