[alsa-devel] [RFC/PATCH v7 03/12] media: Entities, pads and links

Hans Verkuil hverkuil at xs4all.nl
Tue Dec 21 17:22:39 CET 2010


Hi Laurent,

I promised to look at the new type names, so here is my opinion:

On Monday, December 20, 2010 12:36:26 Laurent Pinchart wrote:

<snip>

> +
> +#define MEDIA_ENTITY_TYPE_SHIFT			16
> +#define MEDIA_ENTITY_TYPE_MASK			0x00ff0000
> +#define MEDIA_ENTITY_SUBTYPE_MASK		0x0000ffff
> +
> +#define MEDIA_ENTITY_TYPE_DEVNODE		(1 << MEDIA_ENTITY_TYPE_SHIFT)
> +#define MEDIA_ENTITY_TYPE_DEVNODE_V4L		(MEDIA_ENTITY_TYPE_DEVNODE + 1)
> +#define MEDIA_ENTITY_TYPE_DEVNODE_FB		(MEDIA_ENTITY_TYPE_DEVNODE + 2)
> +#define MEDIA_ENTITY_TYPE_DEVNODE_ALSA		(MEDIA_ENTITY_TYPE_DEVNODE + 3)
> +#define MEDIA_ENTITY_TYPE_DEVNODE_DVB		(MEDIA_ENTITY_TYPE_DEVNODE + 4)
> +
> +#define MEDIA_ENTITY_TYPE_V4L2_SUBDEV		(2 << MEDIA_ENTITY_TYPE_SHIFT)
> +#define MEDIA_ENTITY_TYPE_V4L2_SUBDEV_SENSOR	(MEDIA_ENTITY_TYPE_V4L2_SUBDEV + 1)
> +#define MEDIA_ENTITY_TYPE_V4L2_SUBDEV_FLASH	(MEDIA_ENTITY_TYPE_V4L2_SUBDEV + 2)
> +#define MEDIA_ENTITY_TYPE_V4L2_SUBDEV_LENS	(MEDIA_ENTITY_TYPE_V4L2_SUBDEV + 3)
> +
> +#define MEDIA_ENTITY_FLAG_DEFAULT		(1 << 0)
> +
> +#define MEDIA_LINK_FLAG_ENABLED			(1 << 0)
> +#define MEDIA_LINK_FLAG_IMMUTABLE		(1 << 1)
> +
> +#define MEDIA_PAD_FLAG_INPUT			(1 << 0)
> +#define MEDIA_PAD_FLAG_OUTPUT			(1 << 1)

Using V4L2_SUBDEV instead of just SUBDEV is definitely an improvement.

However, I think the defines are getting way too long and I would propose
to use the ME_ prefix instead of MEDIA_ENTITY_. Also ML_ instead of MEDIA_LINK_
and MP_ instead of MEDIA_PAD_.

That way it is less of an alphabet soup when reading code.

Regards,

	Hans

-- 
Hans Verkuil - video4linux developer - sponsored by Cisco


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