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

From: Vinod Koul
Date: Wed Jun 24 2020 - 03:40:21 EST


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

s/fialure/failure

> 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 <navid.emamdoost@xxxxxxxxx>
> ---
> 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()

> 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

> 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