Re: [PATCH v4 15/79] media: sh_vou: fix pm_runtime_get_sync() usage count

From: Jonathan Cameron
Date: Fri Apr 30 2021 - 12:41:47 EST


On Wed, 28 Apr 2021 16:51:36 +0200
Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> wrote:

> The pm_runtime_get_sync() internally increments the
> dev->power.usage_count without decrementing it, even on errors.
> Replace it by the new pm_runtime_resume_and_get(), introduced by:
> commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
> in order to properly decrement the usage counter and avoid memory
> leaks.
>
> While here, check if the PM runtime error was caught at open time.
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> ---
> drivers/media/platform/sh_vou.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/sh_vou.c b/drivers/media/platform/sh_vou.c
> index 4ac48441f22c..ca4310e26c49 100644
> --- a/drivers/media/platform/sh_vou.c
> +++ b/drivers/media/platform/sh_vou.c
> @@ -1133,7 +1133,11 @@ static int sh_vou_open(struct file *file)
> if (v4l2_fh_is_singular_file(file) &&
> vou_dev->status == SH_VOU_INITIALISING) {
> /* First open */
> - pm_runtime_get_sync(vou_dev->v4l2_dev.dev);
> + err = pm_runtime_resume_and_get(vou_dev->v4l2_dev.dev);
> + if (err < 0) {
> + v4l2_fh_release(file);
> + goto done_open;
> + }
> err = sh_vou_hw_init(vou_dev);
> if (err < 0) {
> pm_runtime_put(vou_dev->v4l2_dev.dev);