Re: [PATCH v4 1/1] media: v4l2-common: Add helper function media_bus_fmt_to_csi2_(bpp|dt)()

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Frank,

Thanks for the update. A few minor comments...

On Wed, May 13, 2026 at 04:59:47PM -0400, Frank Li wrote:
> Add helper function media_bus_fmt_to_csi2_bpp() to get media bus fmt's bpp
> to reduce codes such as
> 
> 	static const struct imx7_csi_pixfmt pixel_formats[] = {
>         {
>                 .fourcc = V4L2_PIX_FMT_UYVY,
>                 .codes  = IMX_BUS_FMTS(
>                         MEDIA_BUS_FMT_UYVY8_2X8,
>                         MEDIA_BUS_FMT_UYVY8_1X16
>                 ),
>                 .yuv    = true,
>                 .bpp    = 16,
>         },
> 	....
> 
> .bpp can be removed from pixel_formats with this helper function.
> 
> CSI2 data type is defined by MIPI Camera Serial Interface 2 Spec Ver4.1.
> See section 9.4.
> 
> Add helper function media_bus_fmt_to_csi2_dt() to convert media bus fmt to
> MIPI defined data type and avoid below duplicated static array in each CSI2
> drivers.
> 
> 	{
> 		.code = MEDIA_BUS_FMT_UYVY8_1X16,
> 		.data_type = MIPI_CSI2_DT_YUV422_8B,
> 	}
> 
> Only add known map for dt type. Need update media_bus_fmt_info when new
> mapping used.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> Change in v4
> - add space after }
> - fix bpps value when m_nXk (m.n*k)
> - add comments about bpp defination. only convert from suffix of
> MEDIA_BUS_FMT_*
> - move struct media_bus_fmt_info to c file
> - change field name fmt to code
> There are some open at
> https://lore.kernel.org/linux-media/20251013-csi-bgr-rgb-v4-0-55eab2caa69f@kernel.org/.
> this version just fix known review comments.
> 
> Change in v3:
> - squash two help function patch to one.
> - use media_bus_fmt_info to do map.
> ---
>  drivers/media/v4l2-core/v4l2-common.c | 178 ++++++++++++++++++++++++++
>  include/media/mipi-csi2.h             |  26 ++++
>  2 files changed, 204 insertions(+)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
> index 554c591e11133..6dba7267f0ff5 100644
> --- a/drivers/media/v4l2-core/v4l2-common.c
> +++ b/drivers/media/v4l2-core/v4l2-common.c
> @@ -46,6 +46,7 @@
>  #include <linux/uaccess.h>
>  #include <asm/io.h>
>  #include <asm/div64.h>
> +#include <media/mipi-csi2.h>
>  #include <media/v4l2-common.h>
>  #include <media/v4l2-device.h>
>  #include <media/v4l2-ctrls.h>
> @@ -806,3 +807,180 @@ struct clk *__devm_v4l2_sensor_clk_get(struct device *dev, const char *id,
>  	return clk_hw->clk;
>  }
>  EXPORT_SYMBOL_GPL(__devm_v4l2_sensor_clk_get);
> +
> +/**
> + * struct media_bus_fmt_info - information about a media bus format
> + * @code: media bus format identifier (MEDIA_BUS_FMT_*)
> + * @dt: data type define in MIPI spec (MIPI_CSI2_DT *)
> + * @bpp: bit width per pixel, which is suffix from MEDIA_BUS_FMT_*, no pad. no
> + *	 compressed data.
> + */
> +struct media_bus_fmt_info {
> +	u32 code;
> +	u8 dt;
> +	u8 bpp;
> +};
> +
> +static const struct media_bus_fmt_info media_bus_fmt_info[] = {
> +	{ .code = MEDIA_BUS_FMT_RGB444_1X12, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_RGB565_1X16, .dt = MIPI_CSI2_DT_RGB565, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_BGR565_2X8_BE, .dt = MIPI_CSI2_DT_RGB565, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_BGR565_2X8_LE, .dt = MIPI_CSI2_DT_RGB565, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_RGB565_2X8_BE, .dt = MIPI_CSI2_DT_RGB565, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_RGB565_2X8_LE, .dt = MIPI_CSI2_DT_RGB565, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_RGB666_1X18, .bpp = 18 },
> +	{ .code = MEDIA_BUS_FMT_RGB666_2X9_BE, .bpp = 18 },
> +	{ .code = MEDIA_BUS_FMT_BGR666_1X18, .bpp = 18 },
> +	{ .code = MEDIA_BUS_FMT_RBG888_1X24, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB666_1X24_CPADHI, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_BGR666_1X24_CPADHI, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB565_1X24_CPADHI, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG, .bpp = 21 },
> +	{ .code = MEDIA_BUS_FMT_BGR888_1X24, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_BGR888_3X8, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_GBR888_1X24, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X24, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_2X12_BE, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_2X12_LE, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_3X8, .dt = MIPI_CSI2_DT_RGB888, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_3X8_DELTA, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG, .bpp = 28 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, .bpp = 28 },
> +	{ .code = MEDIA_BUS_FMT_RGB666_1X30_CPADLO, .bpp = 30 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X30_CPADLO, .bpp = 30 },
> +	{ .code = MEDIA_BUS_FMT_ARGB8888_1X32, .bpp = 32 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X32_PADHI, .bpp = 32 },
> +	{ .code = MEDIA_BUS_FMT_RGB101010_1X30, .bpp = 30 },
> +	{ .code = MEDIA_BUS_FMT_RGB101010_1X7X5_SPWG, .bpp = 35 },
> +	{ .code = MEDIA_BUS_FMT_RGB101010_1X7X5_JEIDA, .bpp = 35 },
> +	{ .code = MEDIA_BUS_FMT_RGB666_1X36_CPADLO, .bpp = 36 },
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X36_CPADLO, .bpp = 36 },
> +	{ .code = MEDIA_BUS_FMT_RGB121212_1X36, .bpp = 36 },
> +	{ .code = MEDIA_BUS_FMT_RGB161616_1X48, .bpp = 48 },
> +
> +	{ .code = MEDIA_BUS_FMT_Y8_1X8, .dt = MIPI_CSI2_DT_RAW8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_UV8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_UYVY8_1_5X8, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_VYUY8_1_5X8, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_YUYV8_1_5X8, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_YVYU8_1_5X8, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_VYUY8_2X8, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_YUYV8_2X8, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_YVYU8_2X8, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_Y10_1X10, .dt = MIPI_CSI2_DT_RAW10, .bpp = 10 },
> +	{ .code = MEDIA_BUS_FMT_Y10_2X8_PADHI_LE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_UYVY10_2X10, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_VYUY10_2X10, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_YVYU10_2X10, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_Y12_1X12, .dt = MIPI_CSI2_DT_RAW12, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_UYVY12_2X12, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_VYUY12_2X12, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_YUYV12_2X12, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_YVYU12_2X12, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_Y14_1X14, .dt = MIPI_CSI2_DT_RAW14, .bpp = 14 },
> +	{ .code = MEDIA_BUS_FMT_Y16_1X16, .dt = MIPI_CSI2_DT_RAW16, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_VYUY8_1X16, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_YUYV8_1X16, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_YVYU8_1X16, .dt = MIPI_CSI2_DT_YUV422_8B, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_YDYUYDYV8_1X16, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_UYVY10_1X20, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_VYUY10_1X20, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_YUYV10_1X20, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_YVYU10_1X20, .dt = MIPI_CSI2_DT_YUV422_10B, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_VUY8_1X24, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_YUV8_1X24, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_UYYVYY8_0_5X24, .dt = MIPI_CSI2_DT_YUV420_8B, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_UYVY12_1X24, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_VYUY12_1X24, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_YUYV12_1X24, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_YVYU12_1X24, .bpp = 24 },
> +	{ .code = MEDIA_BUS_FMT_YUV10_1X30, .bpp = 30 },
> +	{ .code = MEDIA_BUS_FMT_UYYVYY10_0_5X30, .bpp = 15 },
> +	{ .code = MEDIA_BUS_FMT_AYUV8_1X32, .bpp = 32 },
> +	{ .code = MEDIA_BUS_FMT_UYYVYY12_0_5X36, .bpp = 18 },
> +	{ .code = MEDIA_BUS_FMT_YUV12_1X36, .bpp = 36 },
> +	{ .code = MEDIA_BUS_FMT_YUV16_1X48, .bpp = 48 },
> +	{ .code = MEDIA_BUS_FMT_UYYVYY16_0_5X48, .bpp = 24 },
> +
> +	{ .code = MEDIA_BUS_FMT_SBGGR8_1X8, .dt = MIPI_CSI2_DT_RAW8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SGBRG8_1X8, .dt = MIPI_CSI2_DT_RAW8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SGRBG8_1X8, .dt = MIPI_CSI2_DT_RAW8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SRGGB8_1X8, .dt = MIPI_CSI2_DT_RAW8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR10_ALAW8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SGBRG10_ALAW8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SGRBG10_ALAW8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SRGGB10_ALAW8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR10_DPCM8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SGBRG10_DPCM8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SGRBG10_DPCM8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SRGGB10_DPCM8_1X8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR10_2X8_PADHI_BE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR10_2X8_PADHI_LE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR10_2X8_PADLO_BE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR10_2X8_PADLO_LE, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR10_1X10, .dt = MIPI_CSI2_DT_RAW10, .bpp = 10 },
> +	{ .code = MEDIA_BUS_FMT_SGBRG10_1X10, .dt = MIPI_CSI2_DT_RAW10, .bpp = 10 },
> +	{ .code = MEDIA_BUS_FMT_SGRBG10_1X10, .dt = MIPI_CSI2_DT_RAW10, .bpp = 10 },
> +	{ .code = MEDIA_BUS_FMT_SRGGB10_1X10, .dt = MIPI_CSI2_DT_RAW10, .bpp = 10 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR12_1X12, .dt = MIPI_CSI2_DT_RAW12, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_SGBRG12_1X12, .dt = MIPI_CSI2_DT_RAW12, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_SGRBG12_1X12, .dt = MIPI_CSI2_DT_RAW12, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_SRGGB12_1X12, .dt = MIPI_CSI2_DT_RAW12, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR14_1X14, .dt = MIPI_CSI2_DT_RAW14, .bpp = 14 },
> +	{ .code = MEDIA_BUS_FMT_SGBRG14_1X14, .dt = MIPI_CSI2_DT_RAW14, .bpp = 14 },
> +	{ .code = MEDIA_BUS_FMT_SGRBG14_1X14, .dt = MIPI_CSI2_DT_RAW14, .bpp = 14 },
> +	{ .code = MEDIA_BUS_FMT_SRGGB14_1X14, .dt = MIPI_CSI2_DT_RAW14, .bpp = 14 },
> +	{ .code = MEDIA_BUS_FMT_SBGGR16_1X16, .dt = MIPI_CSI2_DT_RAW16, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_SGBRG16_1X16, .dt = MIPI_CSI2_DT_RAW16, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_SGRBG16_1X16, .dt = MIPI_CSI2_DT_RAW16, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_SRGGB16_1X16, .dt = MIPI_CSI2_DT_RAW16, .bpp = 16 },
> +
> +	{ .code = MEDIA_BUS_FMT_JPEG_1X8, .bpp = 8 },
> +
> +	{ .code = MEDIA_BUS_FMT_S5C_UYVY_JPEG_1X8, .bpp = 8 },
> +
> +	{ .code = MEDIA_BUS_FMT_AHSV8888_1X32, .bpp = 8 },
> +
> +	{ .code = MEDIA_BUS_FMT_META_8, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_META_10, .bpp = 10 },
> +	{ .code = MEDIA_BUS_FMT_META_12, .bpp = 12 },
> +	{ .code = MEDIA_BUS_FMT_META_14, .bpp = 14 },
> +	{ .code = MEDIA_BUS_FMT_META_16, .bpp = 16 },
> +	{ .code = MEDIA_BUS_FMT_META_20, .bpp = 20 },
> +	{ .code = MEDIA_BUS_FMT_META_24, .bpp = 24 },
> +};
> +
> +static const struct media_bus_fmt_info *media_bus_fmt_info_get(u32 bus_fmt)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(media_bus_fmt_info); i++) {

Can be defined here.

> +		if (media_bus_fmt_info[i].code == bus_fmt)
> +			return &media_bus_fmt_info[i];
> +	}
> +
> +	return NULL;
> +}
> +
> +u32 media_bus_fmt_to_csi2_dt(int bus_fmt)

u32 for bus_fmt.

> +{
> +	const struct media_bus_fmt_info *info = media_bus_fmt_info_get(bus_fmt);
> +
> +	return info ? info->dt : MIPI_CSI2_DT_INVALIDATE;
> +}
> +EXPORT_SYMBOL_GPL(media_bus_fmt_to_csi2_dt);
> +
> +u32 media_bus_fmt_to_csi2_bpp(int bus_fmt)

Ditto.

> +{
> +	const struct media_bus_fmt_info *info = media_bus_fmt_info_get(bus_fmt);
> +
> +	return info ? info->bpp : 0;
> +}
> +EXPORT_SYMBOL_GPL(media_bus_fmt_to_csi2_bpp);
> diff --git a/include/media/mipi-csi2.h b/include/media/mipi-csi2.h
> index 40fc0264250d7..bd22d2ae57e81 100644
> --- a/include/media/mipi-csi2.h
> +++ b/include/media/mipi-csi2.h
> @@ -44,4 +44,30 @@
>  #define MIPI_CSI2_DT_RAW20		0x2f
>  #define MIPI_CSI2_DT_USER_DEFINED(n)	(0x30 + (n))	/* 0..7 */
>  
> +/* Use one undefined value in spec */
> +#define MIPI_CSI2_DT_INVALIDATE		0xff

s/INVALID\KATE//

> +
> +/**
> + * media_bus_fmt_to_csi2_dt - Get MIPI CSI2 data type from media bus format
> + *
> + * @bus_fmt: media bus format identifier (MEDIA_BUS_FMT_*)
> + *
> + * return MIPI CSI2 data type MIPI_CSI2_DT_*, MIPI_CSI2_DT_INVALIDATE means

 * Return: ...

> + * can't get data type from bus_fmt.
> + */
> +u32 media_bus_fmt_to_csi2_dt(int bus_fmt);

I also realised you'll need linux/types.h for u32.

> +
> +/**
> + * media_bus_fmt_to_csi2_bpp - Get media bus format's bit width per pixel

s/width per pixel/depth/

?

> + *
> + * @bus_fmt: media bus format identifier (MEDIA_BUS_FMT_*)
> + *
> + * returns bit width per pixel, 0 is invalidate width, which can't get from

Ditto.

> + * bus_fmt.
> + *
> + * Notes: this bpp is suffix from MEDIA_BUS_FMT_*, no pad, not for compressed
> + * data.
> + */
> +u32 media_bus_fmt_to_csi2_bpp(int bus_fmt);
> +
>  #endif /* _MEDIA_MIPI_CSI2_H */

-- 
Kind regards,

Sakari Ailus