Re: [PATCH 1/2 v4] v4l: add a media-bus API for configuring v4l2 subdev pixel and frame formats

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thursday 03 December 2009 15:16:56 Guennadi Liakhovetski wrote:
> Video subdevices, like cameras, decoders, connect to video bridges over
> specialised busses. Data is being transferred over these busses in various
> formats, which only loosely correspond to fourcc codes, describing how video
> data is stored in RAM. This is not a one-to-one correspondence, therefore we
> cannot use fourcc codes to configure subdevice output data formats. This patch
> adds codes for several such on-the-bus formats and an API, similar to the
> familiar .s_fmt(), .g_fmt(), .try_fmt(), .enum_fmt() API for configuring those
> codes. After all users of the old API in struct v4l2_subdev_video_ops are
> converted, it will be removed. Also add helper routines to support generic
> pass-through mode for the soc-camera framework.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
> ---
> 
> v3 -> v4: more comments addressed - thanks! Now based on the current 
> linux-next. Hans, as for _nXk suffixes, I preferred to preserve them to 
> keep all notation explicit. Without them a format like 
> V4L2_MBUS_FMT_SBGGR10 would be ambiguous, whether one of 
> V4L2_MBUS_FMT_SBGGR10_2X8_PAD*_?E or the V4L2_MBUS_FMT_SBGGR10_1X10 is 
> meant. I also removed struct soc_mbus_datafmt and soc_mbus_find_datafmt() 
> upon your request, although I'm not happy having to open-code it in about 
> 4 drivers. But we can extract that code in a generic routine later. One of 
> the important advantages of that struct and function was, that they 
> allowed to keep supported formats in drivers centrally at just one 
> location, thus being able to add new or remove deprecated formats easily, 
> and to avoid long switch-case blocks by just calling one function to 
> search in the array.
> 
> Thanks
> Guennadi
> 
>  drivers/media/video/Makefile       |    2 +-
>  drivers/media/video/soc_mediabus.c |  157 ++++++++++++++++++++++++++++++++++++
>  include/media/soc_mediabus.h       |   65 +++++++++++++++
>  include/media/v4l2-mediabus.h      |   61 ++++++++++++++
>  include/media/v4l2-subdev.h        |   19 ++++-
>  5 files changed, 302 insertions(+), 2 deletions(-)
>  create mode 100644 drivers/media/video/soc_mediabus.c
>  create mode 100644 include/media/soc_mediabus.h
>  create mode 100644 include/media/v4l2-mediabus.h
> 
> diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
> index 7a2dcc3..e7bc8da 100644
> --- a/drivers/media/video/Makefile
> +++ b/drivers/media/video/Makefile
> @@ -149,7 +149,7 @@ obj-$(CONFIG_VIDEO_VIVI) += vivi.o
>  obj-$(CONFIG_VIDEO_CX23885) += cx23885/
>  
>  obj-$(CONFIG_VIDEO_OMAP2)		+= omap2cam.o
> -obj-$(CONFIG_SOC_CAMERA)		+= soc_camera.o
> +obj-$(CONFIG_SOC_CAMERA)		+= soc_camera.o soc_mediabus.o
>  obj-$(CONFIG_SOC_CAMERA_PLATFORM)	+= soc_camera_platform.o
>  # soc-camera host drivers have to be linked after camera drivers
>  obj-$(CONFIG_VIDEO_MX1)			+= mx1_camera.o
> diff --git a/drivers/media/video/soc_mediabus.c b/drivers/media/video/soc_mediabus.c
> new file mode 100644
> index 0000000..c54cae7
> --- /dev/null
> +++ b/drivers/media/video/soc_mediabus.c
> @@ -0,0 +1,157 @@
> +/*
> + * soc-camera media bus helper routines
> + *
> + * Copyright (C) 2009, Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
> + *
> + * 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.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-mediabus.h>
> +#include <media/soc_mediabus.h>
> +
> +#define MBUS_IDX(f) (V4L2_MBUS_FMT_ ## f - V4L2_MBUS_FMT_FIXED - 1)
> +
> +static const struct soc_mbus_pixelfmt mbus_fmt[] = {
> +	[MBUS_IDX(YUYV8_2X8)] = {
> +		.fourcc			= V4L2_PIX_FMT_YUYV,
> +		.name			= "YUYV",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(YVYU8_2X8)] = {
> +		.fourcc			= V4L2_PIX_FMT_YVYU,
> +		.name			= "YVYU",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(UYVY8_2X8)] = {
> +		.fourcc			= V4L2_PIX_FMT_UYVY,
> +		.name			= "UYVY",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(VYUY8_2X8)] = {
> +		.fourcc			= V4L2_PIX_FMT_VYUY,
> +		.name			= "VYUY",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(RGB555_2X8_PADHI_LE)] = {
> +		.fourcc			= V4L2_PIX_FMT_RGB555,
> +		.name			= "RGB555",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(RGB555_2X8_PADHI_BE)] = {
> +		.fourcc			= V4L2_PIX_FMT_RGB555X,
> +		.name			= "RGB555X",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(RGB565_2X8_LE)] = {
> +		.fourcc			= V4L2_PIX_FMT_RGB565,
> +		.name			= "RGB565",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(RGB565_2X8_BE)] = {
> +		.fourcc			= V4L2_PIX_FMT_RGB565X,
> +		.name			= "RGB565X",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(SBGGR8_1X8)] = {
> +		.fourcc			= V4L2_PIX_FMT_SBGGR8,
> +		.name			= "Bayer 8 BGGR",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_NONE,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(SBGGR10_1X10)] = {
> +		.fourcc			= V4L2_PIX_FMT_SBGGR10,
> +		.name			= "Bayer 10 BGGR",
> +		.bits_per_sample	= 10,
> +		.packing		= SOC_MBUS_PACKING_EXTEND16,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(GREY8_1X8)] = {
> +		.fourcc			= V4L2_PIX_FMT_GREY,
> +		.name			= "Grey",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_NONE,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(Y10_1X10)] = {
> +		.fourcc			= V4L2_PIX_FMT_Y10,
> +		.name			= "Grey 10bit",
> +		.bits_per_sample	= 10,
> +		.packing		= SOC_MBUS_PACKING_EXTEND16,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(SBGGR10_2X8_PADHI_LE)] = {
> +		.fourcc			= V4L2_PIX_FMT_SBGGR10,
> +		.name			= "Bayer 10 BGGR",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(SBGGR10_2X8_PADLO_LE)] = {
> +		.fourcc			= V4L2_PIX_FMT_SBGGR10,
> +		.name			= "Bayer 10 BGGR",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADLO,
> +		.order			= SOC_MBUS_ORDER_LE,
> +	}, [MBUS_IDX(SBGGR10_2X8_PADHI_BE)] = {
> +		.fourcc			= V4L2_PIX_FMT_SBGGR10,
> +		.name			= "Bayer 10 BGGR",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
> +		.order			= SOC_MBUS_ORDER_BE,
> +	}, [MBUS_IDX(SBGGR10_2X8_PADLO_BE)] = {
> +		.fourcc			= V4L2_PIX_FMT_SBGGR10,
> +		.name			= "Bayer 10 BGGR",
> +		.bits_per_sample	= 8,
> +		.packing		= SOC_MBUS_PACKING_2X8_PADLO,
> +		.order			= SOC_MBUS_ORDER_BE,
> +	},
> +};
> +
> +s32 soc_mbus_bytes_per_line(u32 width, const struct soc_mbus_pixelfmt *mf)
> +{
> +	switch (mf->packing) {
> +	case SOC_MBUS_PACKING_NONE:
> +		return width * mf->bits_per_sample / 8;
> +	case SOC_MBUS_PACKING_2X8_PADHI:
> +	case SOC_MBUS_PACKING_2X8_PADLO:
> +	case SOC_MBUS_PACKING_EXTEND16:
> +		return width * 2;
> +	}
> +	return -EINVAL;
> +}
> +EXPORT_SYMBOL(soc_mbus_bytes_per_line);
> +
> +const struct soc_mbus_pixelfmt *soc_mbus_get_fmtdesc(
> +	enum v4l2_mbus_pixelcode code)
> +{
> +	if ((unsigned int)(code - V4L2_MBUS_FMT_FIXED) > ARRAY_SIZE(mbus_fmt))
> +		return NULL;
> +	return mbus_fmt + code - V4L2_MBUS_FMT_FIXED - 1;
> +}
> +EXPORT_SYMBOL(soc_mbus_get_fmtdesc);
> +
> +static int __init soc_mbus_init(void)
> +{
> +	return 0;
> +}
> +
> +static void __exit soc_mbus_exit(void)
> +{
> +}
> +
> +module_init(soc_mbus_init);
> +module_exit(soc_mbus_exit);
> +
> +MODULE_DESCRIPTION("soc-camera media bus interface");
> +MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@xxxxxx>");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/media/soc_mediabus.h b/include/media/soc_mediabus.h
> new file mode 100644
> index 0000000..037cd7b
> --- /dev/null
> +++ b/include/media/soc_mediabus.h
> @@ -0,0 +1,65 @@
> +/*
> + * SoC-camera Media Bus API extensions
> + *
> + * Copyright (C) 2009, Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
> + *
> + * 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 SOC_MEDIABUS_H
> +#define SOC_MEDIABUS_H
> +
> +#include <linux/videodev2.h>
> +
> +#include <media/v4l2-mediabus.h>
> +
> +/**
> + * enum soc_mbus_packing - data packing types on the media-bus
> + * @SOC_MBUS_PACKING_NONE:	no packing, bit-for-bit transfer to RAM
> + * @SOC_MBUS_PACKING_2X8_PADHI:	16 bits transferred in 2 8-bit samples, in the
> + *				possibly incomplete byte high bits are padding
> + * @SOC_MBUS_PACKING_2X8_PADLO:	as above, but low bits are padding
> + * @SOC_MBUS_PACKING_EXTEND16:	sample width (e.g., 10 bits) has to be extended
> + *				to 16 bits
> + */
> +enum soc_mbus_packing {
> +	SOC_MBUS_PACKING_NONE,
> +	SOC_MBUS_PACKING_2X8_PADHI,
> +	SOC_MBUS_PACKING_2X8_PADLO,
> +	SOC_MBUS_PACKING_EXTEND16,
> +};
> +
> +/**
> + * enum soc_mbus_order - sample order on the media bus
> + * @SOC_MBUS_ORDER_LE:		least significant sample first
> + * @SOC_MBUS_ORDER_BE:		most significant sample first
> + */
> +enum soc_mbus_order {
> +	SOC_MBUS_ORDER_LE,
> +	SOC_MBUS_ORDER_BE,
> +};
> +
> +/**
> + * struct soc_mbus_pixelfmt - Data format on the media bus
> + * @name:		Name of the format
> + * @fourcc:		Fourcc code, that will be obtained if the data is
> + *			stored in memory in the following way:
> + * @packing:		Type of sample-packing, that has to be used
> + * @order:		Sample order when storing in memory
> + * @bits_per_sample:	How many bits the bridge has to sample
> + */
> +struct soc_mbus_pixelfmt {
> +	const char		*name;
> +	u32			fourcc;
> +	enum soc_mbus_packing	packing;
> +	enum soc_mbus_order	order;
> +	u8			bits_per_sample;
> +};
> +
> +const struct soc_mbus_pixelfmt *soc_mbus_get_fmtdesc(
> +	enum v4l2_mbus_pixelcode code);
> +s32 soc_mbus_bytes_per_line(u32 width, const struct soc_mbus_pixelfmt *mf);
> +
> +#endif
> diff --git a/include/media/v4l2-mediabus.h b/include/media/v4l2-mediabus.h
> new file mode 100644
> index 0000000..5cf2a6d
> --- /dev/null
> +++ b/include/media/v4l2-mediabus.h
> @@ -0,0 +1,61 @@
> +/*
> + * Media Bus API header
> + *
> + * Copyright (C) 2009, Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
> + *
> + * 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 V4L2_MEDIABUS_H
> +#define V4L2_MEDIABUS_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,

Darn, I was so hoping that I could sign off on it, but this makes no sense
now.

Either it is:

	V4L2_MBUS_FMT_YUYV8_1X8,
	V4L2_MBUS_FMT_YVYU8_1X8,
	V4L2_MBUS_FMT_UYVY8_1X8,
	V4L2_MBUS_FMT_VYUY8_1X8

where the 'YUYV' code tells you the order of the Y, U and V samples over the
bus, or it is:

	V4L2_MBUS_FMT_YUYV8_2X8_BE,
	V4L2_MBUS_FMT_YUYV8_2X8_LE,
	V4L2_MBUS_FMT_YVYU8_2X8_BE,
	V4L2_MBUS_FMT_YVYU8_2X8_LE,

Where the BE or LE suffix tells you the order in which the YU/YV pairs are
arriving.

Personally I prefer the first (1X8) representation.

Just pick one of these two and you can send it again and add my signed-off-by:

Signed-off-by: Hans Verkuil <hverkuil@xxxxxxxxx>

Regards,

	Hans

> +	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,
> +};
> +
> +/**
> + * 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;
> +	enum v4l2_mbus_pixelcode	code;
> +	enum v4l2_field			field;
> +	enum v4l2_colorspace		colorspace;
> +};
> +
> +#endif
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index 544ce87..c53d462 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -22,6 +22,7 @@
>  #define _V4L2_SUBDEV_H
>  
>  #include <media/v4l2-common.h>
> +#include <media/v4l2-mediabus.h>
>  
>  /* generic v4l2_device notify callback notification values */
>  #define V4L2_SUBDEV_IR_RX_NOTIFY		_IOW('v', 0, u32)
> @@ -207,7 +208,7 @@ struct v4l2_subdev_audio_ops {
>     s_std_output: set v4l2_std_id for video OUTPUT devices. This is ignored by
>  	video input devices.
>  
> -  s_crystal_freq: sets the frequency of the crystal used to generate the
> +   s_crystal_freq: sets the frequency of the crystal used to generate the
>  	clocks in Hz. An extra flags field allows device specific configuration
>  	regarding clock frequency dividers, etc. If not used, then set flags
>  	to 0. If the frequency is not supported, then -EINVAL is returned.
> @@ -217,6 +218,14 @@ struct v4l2_subdev_audio_ops {
>  
>     s_routing: see s_routing in audio_ops, except this version is for video
>  	devices.
> +
> +   enum_mbus_fmt: enumerate pixel formats, provided by a video data source
> +
> +   g_mbus_fmt: get the current pixel format, provided by a video data source
> +
> +   try_mbus_fmt: try to set a pixel format on a video data source
> +
> +   s_mbus_fmt: set a pixel format on a video data source
>   */
>  struct v4l2_subdev_video_ops {
>  	int (*s_routing)(struct v4l2_subdev *sd, u32 input, u32 output, u32 config);
> @@ -240,6 +249,14 @@ struct v4l2_subdev_video_ops {
>  	int (*s_parm)(struct v4l2_subdev *sd, struct v4l2_streamparm *param);
>  	int (*enum_framesizes)(struct v4l2_subdev *sd, struct v4l2_frmsizeenum *fsize);
>  	int (*enum_frameintervals)(struct v4l2_subdev *sd, struct v4l2_frmivalenum *fival);
> +	int (*enum_mbus_fmt)(struct v4l2_subdev *sd, int index,
> +			     enum v4l2_mbus_pixelcode *code);
> +	int (*g_mbus_fmt)(struct v4l2_subdev *sd,
> +			  struct v4l2_mbus_framefmt *fmt);
> +	int (*try_mbus_fmt)(struct v4l2_subdev *sd,
> +			    struct v4l2_mbus_framefmt *fmt);
> +	int (*s_mbus_fmt)(struct v4l2_subdev *sd,
> +			  struct v4l2_mbus_framefmt *fmt);
>  };
>  
>  /**
> -- 
> 1.6.2.4
> 
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux Input]     [Video for Linux]     [Gstreamer Embedded]     [Mplayer Users]     [Linux USB Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]
  Powered by Linux