Re: [PATCH 1/2] [media] media-device: check before unregister if mdev was registered

From: Sakari Ailus
Date: Thu Sep 10 2015 - 13:16:21 EST


Javier Martinez Canillas wrote:
> Most media functions that unregister, check if the corresponding register
> function succeed before. So these functions can safely be called even if a
> registration was never made or the component as already been unregistered.
>
> Add the same check to media_device_unregister() function for consistency.
>
> This will also allow to split the media_device_register() function in an
> initialization and registration functions without the need to change the
> generic cleanup functions and error code paths for all the media drivers.
>
> Suggested-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> Signed-off-by: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>
> ---
>
> drivers/media/media-device.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
> index 1312e93ebd6e..745defb34b33 100644
> --- a/drivers/media/media-device.c
> +++ b/drivers/media/media-device.c
> @@ -574,6 +574,8 @@ EXPORT_SYMBOL_GPL(__media_device_register);
> * media_device_unregister - unregister a media device
> * @mdev: The media device
> *
> + * If the media device has never been registered this function will
> + * return immediately.

I'd say "It is safe to call this function on an unregistered (but
initialised) media device.". Up to you.

Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>

--
Sakari Ailus
sakari.ailus@xxxxxxxxxxxxxxx
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