ioctl VIDIOC_G_DV_TIMINGS, VIDIOC_S_DV_TIMINGS
&manvol;

# VIDIOC_G_DV_TIMINGS

# VIDIOC_S_DV_TIMINGS

Get or set custom DV timings for input or output

    	int ioctl
    	int fd
    	int request
    	struct v4l2_dv_timings *argp

## Arguments

`fd`

  &fd;

`request`

  VIDIOC_G_DV_TIMINGS, VIDIOC_S_DV_TIMINGS

`argp`

## Description

To set custom DV timings for the input or output, applications use the `VIDIOC_S_DV_TIMINGS` ioctl and to get the current custom timings, applications use the `VIDIOC_G_DV_TIMINGS` ioctl. The detailed timing information is filled in using the structure &v4l2-dv-timings;. These ioctls take a pointer to the &v4l2-dv-timings; structure as argument. If the ioctl is not supported or the timing values are not correct, the driver returns &EINVAL;.

&return-value;

EINVAL

  This ioctl is not supported, or the `VIDIOC_S_DV_TIMINGS` parameter was unsuitable.

EBUSY

  The device is busy and therefore can not change the timings.

### struct v4l2_bt_timings

&cs-str;
__u32 | width | Width of the active video in pixels
__u32 | height | Height of the active video in lines
__u32 | interlaced | Progressive (0) or interlaced (1)
__u32 | polarities | This is a bit mask that defines polarities of sync signals. bit 0 (V4L2_DV_VSYNC_POS_POL) is for vertical sync polarity and bit 1 (V4L2_DV_HSYNC_POS_POL) is for horizontal sync polarity. If the bit is set (1) it is positive polarity and if is cleared (0), it is negative polarity.
__u64 | pixelclock | Pixel clock in Hz. Ex. 74.25MHz->74250000
__u32 | hfrontporch | Horizontal front porch in pixels
__u32 | hsync | Horizontal sync length in pixels
__u32 | hbackporch | Horizontal back porch in pixels
__u32 | vfrontporch | Vertical front porch in lines
__u32 | vsync | Vertical sync length in lines
__u32 | vbackporch | Vertical back porch in lines
__u32 | il_vfrontporch | Vertical front porch in lines for bottom field of interlaced field formats
__u32 | il_vsync | Vertical sync length in lines for bottom field of interlaced field formats
__u32 | il_vbackporch | Vertical back porch in lines for bottom field of interlaced field formats

### struct v4l2_dv_timings

&cs-str;
__u32 | type |  | Type of DV timings as listed in .
union |  |
| &v4l2-bt-timings; | bt | Timings defined by BT.656/1120 specifications
| __u32 | reserved[32] |

### DV Timing types

&cs-str;
Timing type | value | Description
V4L2_DV_BT_656_1120 | 0 | BT.656/1120 timings