[PATCH] engine: stm32-dma: call pm_runtime_put if pm_runtime_get_sync fails

From: Navid Emamdoost
Date: Wed Jun 03 2020 - 14:34:25 EST


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

Signed-off-by: Navid Emamdoost <navid.emamdoost@xxxxxxxxx>
---
drivers/dma/stm32-dma.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index 0ddbaa4b4f0b..0aab86bd97fe 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -1169,8 +1169,10 @@ static int stm32_dma_alloc_chan_resources(struct dma_chan *c)
chan->config_init = false;

ret = pm_runtime_get_sync(dmadev->ddev.dev);
- if (ret < 0)
+ if (ret < 0) {
+ pm_runtime_put(dmadev->ddev.dev);
return ret;
+ }

ret = stm32_dma_disable_chan(chan);
if (ret < 0)
@@ -1439,8 +1441,10 @@ static int stm32_dma_suspend(struct device *dev)
int id, ret, scr;

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

for (id = 0; id < STM32_DMA_MAX_CHANNELS; id++) {
scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id));
--
2.17.1