Re: [PATCH/RFC v3 01/11] v4l: Move the media/v4l2-mediabus.h header to include/linux

[Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>]

Hi Laurent,

Thanks for the patch!

Laurent Pinchart wrote:
> The header defines the v4l2_mbus_framefmt structure which will be used
> by the V4L2 subdevs userspace API.
> 
> Change the type of the v4l2_mbus_framefmt::code field to __u32, as enum
> sizes can differ between different ABIs on the same architectures.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  include/linux/Kbuild          |    1 +
>  include/linux/v4l2-mediabus.h |   70 +++++++++++++++++++++++++++++++++++++++++
>  include/media/soc_mediabus.h  |    3 +-
>  include/media/v4l2-mediabus.h |   53 +------------------------------
>  4 files changed, 73 insertions(+), 54 deletions(-)
>  create mode 100644 include/linux/v4l2-mediabus.h
> 
> diff --git a/include/linux/Kbuild b/include/linux/Kbuild
> index f836ee4..38127c2 100644
> --- a/include/linux/Kbuild
> +++ b/include/linux/Kbuild
> @@ -369,6 +369,7 @@ header-y += unistd.h
>  header-y += usbdevice_fs.h
>  header-y += utime.h
>  header-y += utsname.h
> +header-y += v4l2-mediabus.h
>  header-y += veth.h
>  header-y += vhost.h
>  header-y += videodev.h
> diff --git a/include/linux/v4l2-mediabus.h b/include/linux/v4l2-mediabus.h
> new file mode 100644
> index 0000000..127512a
> --- /dev/null
> +++ b/include/linux/v4l2-mediabus.h
> @@ -0,0 +1,70 @@
> +/*
> + * Media Bus API header
> + *
> + * Copyright (C) 2009, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#ifndef __LINUX_V4L2_MEDIABUS_H
> +#define __LINUX_V4L2_MEDIABUS_H
> +
> +#include <linux/types.h>
> +#include <linux/videodev2.h>
> +
> +/*
> + * These pixel codes uniquely identify data formats on the media bus. Mostly
> + * they correspond to similarly named V4L2_PIX_FMT_* formats, format 0 is
> + * reserved, V4L2_MBUS_FMT_FIXED shall be used by host-client pairs, where the
> + * data format is fixed. Additionally, "2X8" means that one pixel is transferred
> + * in two 8-bit samples, "BE" or "LE" specify in which order those samples are
> + * transferred over the bus: "LE" means that the least significant bits are
> + * transferred first, "BE" means that the most significant bits are transferred
> + * first, and "PADHI" and "PADLO" define which bits - low or high, in the
> + * incomplete high byte, are filled with padding bits.
> + */
> +enum v4l2_mbus_pixelcode {
> +	V4L2_MBUS_FMT_FIXED = 1,
> +	V4L2_MBUS_FMT_YUYV8_2X8,
> +	V4L2_MBUS_FMT_YVYU8_2X8,
> +	V4L2_MBUS_FMT_UYVY8_2X8,
> +	V4L2_MBUS_FMT_VYUY8_2X8,
> +	V4L2_MBUS_FMT_RGB555_2X8_PADHI_LE,
> +	V4L2_MBUS_FMT_RGB555_2X8_PADHI_BE,
> +	V4L2_MBUS_FMT_RGB565_2X8_LE,
> +	V4L2_MBUS_FMT_RGB565_2X8_BE,
> +	V4L2_MBUS_FMT_SBGGR8_1X8,
> +	V4L2_MBUS_FMT_SBGGR10_1X10,
> +	V4L2_MBUS_FMT_GREY8_1X8,
> +	V4L2_MBUS_FMT_Y10_1X10,
> +	V4L2_MBUS_FMT_SBGGR10_2X8_PADHI_LE,
> +	V4L2_MBUS_FMT_SBGGR10_2X8_PADLO_LE,
> +	V4L2_MBUS_FMT_SBGGR10_2X8_PADHI_BE,
> +	V4L2_MBUS_FMT_SBGGR10_2X8_PADLO_BE,
> +	V4L2_MBUS_FMT_SGRBG8_1X8,
> +	V4L2_MBUS_FMT_SBGGR12_1X12,
> +	V4L2_MBUS_FMT_YUYV8_1_5X8,
> +	V4L2_MBUS_FMT_YVYU8_1_5X8,
> +	V4L2_MBUS_FMT_UYVY8_1_5X8,
> +	V4L2_MBUS_FMT_VYUY8_1_5X8,
> +};
> +
> +/**
> + * struct v4l2_mbus_framefmt - frame format on the media bus
> + * @width:	frame width
> + * @height:	frame height
> + * @code:	data format code
> + * @field:	used interlacing type
> + * @colorspace:	colorspace of the data
> + */
> +struct v4l2_mbus_framefmt {
> +	__u32				width;
> +	__u32				height;
> +	__u32				code;
> +	enum v4l2_field			field;
> +	enum v4l2_colorspace		colorspace;
> +};

I think this struct would benefit from some reserved fields since it's
part of the user space interface.

No other comments.

Cheers,

-- 
Sakari Ailus
sakari.ailus@maxwell.research.nokia.com