[PATCH] dmaengine: stm32-dmamux: fix pm_runtime_get_sync fialure cases

Calling pm_runtime_get_sync increments the counter even in case of
failure, causing incorrect ref count. Call pm_runtime_put_sync if
pm_runtime_get_sync fails.

Signed-off-by: Navid Emamdoost <redacted>
---
 drivers/dma/stm32-dmamux.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c
index 12f7637e13a1..ab250d7eed29 100644
--- a/drivers/dma/stm32-dmamux.c
+++ b/drivers/dma/stm32-dmamux.c

@@ -140,6 +140,7 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec,
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret < 0) {
 		spin_unlock_irqrestore(&dmamux->lock, flags);
+		pm_runtime_put_sync(&pdev->dev);
 		goto error;
 	}
 	spin_unlock_irqrestore(&dmamux->lock, flags);

@@ -340,8 +341,10 @@ static int stm32_dmamux_suspend(struct device *dev)
 	int i, ret;
 
 	ret = pm_runtime_get_sync(dev);
-	if (ret < 0)
+	if (ret < 0) {
+		pm_runtime_put_sync(dev);
 		return ret;
+	}
 
 	for (i = 0; i < stm32_dmamux->dma_requests; i++)
 		stm32_dmamux->ccr[i] = stm32_dmamux_read(stm32_dmamux->iomem,

-- 
2.17.1

On 03-06-20, 14:36, Navid Emamdoost wrote:

s/fialure/failure

why put_sync()

here too

 		return ret;
+	}
 
 	for (i = 0; i < stm32_dmamux->dma_requests; i++)
 		stm32_dmamux->ccr[i] = stm32_dmamux_read(stm32_dmamux->iomem,
-- 
2.17.1

-- 
~Vinod

On Wed, Jun 24, 2020 at 2:40 AM Vinod Koul [off-list ref] wrote:

On 03-06-20, 14:36, Navid Emamdoost wrote:

s/fialure/failure

quoted

Calling pm_runtime_get_sync increments the counter even in case of
failure, causing incorrect ref count. Call pm_runtime_put_sync if
pm_runtime_get_sync fails.

Signed-off-by: Navid Emamdoost <redacted>
---
 drivers/dma/stm32-dmamux.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c
index 12f7637e13a1..ab250d7eed29 100644
--- a/drivers/dma/stm32-dmamux.c
+++ b/drivers/dma/stm32-dmamux.c

@@ -140,6 +140,7 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec,
      ret = pm_runtime_get_sync(&pdev->dev);
      if (ret < 0) {
              spin_unlock_irqrestore(&dmamux->lock, flags);
+             pm_runtime_put_sync(&pdev->dev);

why put_sync()

quoted

              goto error;
      }
      spin_unlock_irqrestore(&dmamux->lock, flags);

@@ -340,8 +341,10 @@ static int stm32_dmamux_suspend(struct device *dev)
      int i, ret;

      ret = pm_runtime_get_sync(dev);
-     if (ret < 0)
+     if (ret < 0) {
+             pm_runtime_put_sync(dev);

here too

Is put_noidle() better?

quoted

              return ret;
+     }

      for (i = 0; i < stm32_dmamux->dma_requests; i++)
              stm32_dmamux->ccr[i] = stm32_dmamux_read(stm32_dmamux->iomem,
--
2.17.1

--
~Vinod

-- 
Navid.