7.58. ioctl VIDIOC_SUBDEV_ENUM_MBUS_CODE

7.58.1. Name

VIDIOC_SUBDEV_ENUM_MBUS_CODE - Enumerate media bus formats

7.58.2. Synopsis

VIDIOC_SUBDEV_ENUM_MBUS_CODE

int ioctl(int fd, VIDIOC_SUBDEV_ENUM_MBUS_CODE, struct v4l2_subdev_mbus_code_enum * argp)

7.58.3. Arguments

fd

File descriptor returned by open().

argp

Pointer to struct v4l2_subdev_mbus_code_enum.

7.58.4. Description

This call is used by the application to access the enumeration of media bus formats for the selected pad.

The enumerations are defined by the driver, and indexed using the index field of struct v4l2_subdev_mbus_code_enum. Each enumeration starts with the index of 0, and the lowest invalid index marks the end of enumeration.

Therefore, to enumerate media bus formats available at a given sub-device pad, initialize the pad, and which fields to desired values, and set index to 0. Then call the ioctl VIDIOC_SUBDEV_ENUM_MBUS_CODE ioctl with a pointer to this structure.

A successful call will return with the code field filled in with a mbus code value. Repeat with increasing index until EINVAL is received. EINVAL means that either pad is invalid, or that there are no more codes available at this pad.

The driver must not return the same value of code for different indices at the same pad.

Available media bus formats may depend on the current ‘try’ formats at other pads of the sub-device, as well as on the current active links. See ioctl VIDIOC_SUBDEV_G_FMT, VIDIOC_SUBDEV_S_FMT for more information about the try formats.

type v4l2_subdev_mbus_code_enum

struct v4l2_subdev_mbus_code_enum

__u32	pad	Pad number as reported by the media controller API. Filled in by the application.
__u32	index	Index of the mbus code in the enumeration belonging to the given pad. Filled in by the application.
__u32	code	The media bus format code, as defined in Media Bus Formats. Filled in by the driver.
__u32	which	Media bus format codes to be enumerated, from enum v4l2_subdev_format_whence.
__u32	flags	See Subdev Media Bus Code Enumerate Flags
__u32	stream	Stream identifier.
__u32	reserved[6]	Reserved for future extensions. Applications and drivers must set the array to zero.

Subdev Media Bus Code Enumerate Flags

V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE	0x00000001	The driver allows the application to try to change the default colorspace encoding. The application can ask to configure the colorspace of the subdevice when calling the VIDIOC_SUBDEV_S_FMT ioctl with V4L2_MBUS_FRAMEFMT_SET_CSC set. See Media Bus Formats on how to do this.
V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC	0x00000002	The driver allows the application to try to change the default transform function. The application can ask to configure the transform function of the subdevice when calling the VIDIOC_SUBDEV_S_FMT ioctl with V4L2_MBUS_FRAMEFMT_SET_CSC set. See Media Bus Formats on how to do this.
V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC	0x00000004	The driver allows the application to try to change the default Y’CbCr encoding. The application can ask to configure the Y’CbCr encoding of the subdevice when calling the VIDIOC_SUBDEV_S_FMT ioctl with V4L2_MBUS_FRAMEFMT_SET_CSC set. See Media Bus Formats on how to do this.
V4L2_SUBDEV_MBUS_CODE_CSC_HSV_ENC	0x00000004	The driver allows the application to try to change the default HSV encoding. The application can ask to configure the HSV encoding of the subdevice when calling the VIDIOC_SUBDEV_S_FMT ioctl with V4L2_MBUS_FRAMEFMT_SET_CSC set. See Media Bus Formats on how to do this.
V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION	0x00000008	The driver allows the application to try to change the default quantization. The application can ask to configure the quantization of the subdevice when calling the VIDIOC_SUBDEV_S_FMT ioctl with V4L2_MBUS_FRAMEFMT_SET_CSC set. See Media Bus Formats on how to do this.

7.58.5. Return Value

On success 0 is returned, on error -1 and the errno variable is set appropriately. The generic error codes are described at the Generic Error Codes chapter.

EINVAL

The struct v4l2_subdev_mbus_code_enum pad references a non-existing pad, the which field has an unsupported value, or the index field is out of bounds.