Em Wed, 7 Jun 2017 10:52:07 +0100
Kieran Bingham <kbingham@xxxxxxxxxx> escreveu:
> From: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
>
> Return NULL, if a null entity is parsed for it's v4l2_subdev
>
> Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
Could you please improve this patch description?
I'm unsure if this is a bug fix, or some sort of feature...
On what situations would a null entity be passed to this function?
Regards,
Mauro
>
> ---
> Not sure if this patch ever made it out of my mailbox:
>
> Here's the respin with the parameter evaluated only once.
>
> v4:
> - Improve macro usage to evaluate ent only once
>
> include/media/v4l2-subdev.h | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index a40760174797..0f92ebd2d710 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -826,8 +826,15 @@ struct v4l2_subdev {
> struct v4l2_subdev_platform_data *pdata;
> };
>
> -#define media_entity_to_v4l2_subdev(ent) \
> - container_of(ent, struct v4l2_subdev, entity)
> +#define media_entity_to_v4l2_subdev(ent) \
> +({ \
> + typeof(ent) __me_sd_ent = (ent); \
> + \
> + __me_sd_ent ? \
> + container_of(__me_sd_ent, struct v4l2_subdev, entity) : \
> + NULL; \
> +})
> +
> #define vdev_to_v4l2_subdev(vdev) \
> ((struct v4l2_subdev *)video_get_drvdata(vdev))
>
Thanks,
Mauro
