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¶
__u32 |
|
Pad number as reported by the media controller API. Filled in by the application. |
__u32 |
|
Index of the mbus code in the enumeration belonging to the given pad. Filled in by the application. |
__u32 |
|
The media bus format code, as defined in Media Bus Formats. Filled in by the driver. |
__u32 |
|
Media bus format codes to be enumerated, from enum v4l2_subdev_format_whence. |
__u32 |
|
|
__u32 |
|
Stream identifier. |
__u32 |
|
Reserved for future extensions. Applications and drivers must set the array to zero. |
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, thewhich
field has an unsupported value, or theindex
field is out of bounds.