Re: [PATCH 1/5] uapi/linux/media.h: add flags field to struct media_v2_topology

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Niklas,

Thank you for the patch.

On Thu, Jun 11, 2020 at 01:05:37AM +0200, Niklas Söderlund wrote:
> Add a flags field to the media_v2_topology structure by taking one
> of the reserved u32 fields. Also define a flag to carry information
> about if the graph is complete. The use-case is to have a way to report
> to user-space if the media graph contains all subdevices.
> 
> The other bits in the flags field are unused for now, but could be
> claimed to carry other type of information in the future.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  drivers/media/mc/mc-device.c | 2 +-
>  include/uapi/linux/media.h   | 4 +++-
>  2 files changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/mc/mc-device.c b/drivers/media/mc/mc-device.c
> index da8088351135298a..c2ef5bb512a5fba0 100644
> --- a/drivers/media/mc/mc-device.c
> +++ b/drivers/media/mc/mc-device.c
> @@ -242,6 +242,7 @@ static long media_device_get_topology(struct media_device *mdev, void *arg)
>  	int ret = 0;
>  
>  	topo->topology_version = mdev->topology_version;
> +	topo->flags = 0;
>  
>  	/* Get entities and number of entities */
>  	i = 0;
> @@ -269,7 +270,6 @@ static long media_device_get_topology(struct media_device *mdev, void *arg)
>  		uentity++;
>  	}
>  	topo->num_entities = i;
> -	topo->reserved1 = 0;
>  
>  	/* Get interfaces and number of interfaces */
>  	i = 0;
> diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
> index 383ac7b7d8f07eca..7c07b9939252c768 100644
> --- a/include/uapi/linux/media.h
> +++ b/include/uapi/linux/media.h
> @@ -351,7 +351,7 @@ struct media_v2_topology {
>  	__u64 topology_version;
>  
>  	__u32 num_entities;
> -	__u32 reserved1;
> +	__u32 flags;
>  	__u64 ptr_entities;
>  
>  	__u32 num_interfaces;
> @@ -367,6 +367,8 @@ struct media_v2_topology {
>  	__u64 ptr_links;
>  } __attribute__ ((packed));
>  
> +#define MEDIA_TOPOLOGY_FLAG_COMPLETE	(1 << 0)
> +

Missing documentation :-)

Should we use the BIT() macro ?

>  /* ioctls */
>  
>  #define MEDIA_IOC_DEVICE_INFO	_IOWR('|', 0x00, struct media_device_info)

-- 
Regards,

Laurent Pinchart