VIDIOC_G_DV_PRESET, VIDIOC_S_DV_PRESET — Query or select the DV preset of the current input or output
int ioctl( | int fd, |
| int request, | |
struct v4l2_dv_preset *argp); |
To query and select the current DV preset, applications
use the VIDIOC_G_DV_PRESET and VIDIOC_S_DV_PRESET
ioctls which take a pointer to a struct v4l2_dv_preset type as argument.
Applications must zero the reserved array in struct v4l2_dv_preset.
VIDIOC_G_DV_PRESET returns a dv preset in the field
preset of struct v4l2_dv_preset.
VIDIOC_S_DV_PRESET accepts a pointer to a struct v4l2_dv_preset
that has the preset value to be set. Applications must zero the reserved array in struct v4l2_dv_preset.
If the preset is not supported, it returns an EINVAL error code
On success 0 is returned, on error -1 and the errno variable is set appropriately:
This ioctl is not supported, or the
VIDIOC_S_DV_PRESET,VIDIOC_S_DV_PRESET parameter was unsuitable.
The device is busy and therefore can not change the preset.
Table A.42. struct v4l2_dv_preset
| __u32 | preset | Preset value to represent the digital video timings |
| __u32 | reserved[4] | Reserved fields for future use |