From 8e4bff4cab0ddac6060645b0715210484d02ff40 Mon Sep 17 00:00:00 2001 From: Yuval Adam <_@yuv.al> Date: Wed, 30 Aug 2017 08:25:59 +0000 Subject: Initial file dump from open source release --- .../DocBook/media/v4l/vidioc-subdev-g-edid.xml | 152 +++++++++++++++++++++ 1 file changed, 152 insertions(+) create mode 100644 Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml (limited to 'Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml') diff --git a/Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml b/Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml new file mode 100644 index 00000000..bbd18f0e --- /dev/null +++ b/Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml @@ -0,0 +1,152 @@ + + + ioctl VIDIOC_SUBDEV_G_EDID, VIDIOC_SUBDEV_S_EDID + &manvol; + + + + VIDIOC_SUBDEV_G_EDID + VIDIOC_SUBDEV_S_EDID + Get or set the EDID of a video receiver/transmitter + + + + + + int ioctl + int fd + int request + struct v4l2_subdev_edid *argp + + + + + int ioctl + int fd + int request + const struct v4l2_subdev_edid *argp + + + + + + Arguments + + + + fd + + &fd; + + + + request + + VIDIOC_SUBDEV_G_EDID, VIDIOC_SUBDEV_S_EDID + + + + argp + + + + + + + + + Description + These ioctls can be used to get or set an EDID associated with an input pad + from a receiver or an output pad of a transmitter subdevice. + + To get the EDID data the application has to fill in the pad, + start_block, blocks and edid + fields and call VIDIOC_SUBDEV_G_EDID. The current EDID from block + start_block and of size blocks + will be placed in the memory edid points to. The edid + pointer must point to memory at least blocks * 128 bytes + large (the size of one block is 128 bytes). + + If there are fewer blocks than specified, then the driver will set blocks + to the actual number of blocks. If there are no EDID blocks available at all, then the error code + ENODATA is set. + + If blocks have to be retrieved from the sink, then this call will block until they + have been read. + + To set the EDID blocks of a receiver the application has to fill in the pad, + blocks and edid fields and set + start_block to 0. It is not possible to set part of an EDID, + it is always all or nothing. Setting the EDID data is only valid for receivers as it makes + no sense for a transmitter. + + The driver assumes that the full EDID is passed in. If there are more EDID blocks than + the hardware can handle then the EDID is not written, but instead the error code E2BIG is set + and blocks is set to the maximum that the hardware supports. + If start_block is any + value other than 0 then the error code EINVAL is set. + + To disable an EDID you set blocks to 0. Depending on the + hardware this will drive the hotplug pin low and/or block the source from reading the EDID + data in some way. In any case, the end result is the same: the EDID is no longer available. + + + + struct <structname>v4l2_subdev_edid</structname> + + &cs-str; + + + __u32 + pad + Pad for which to get/set the EDID blocks. + + + __u32 + start_block + Read the EDID from starting with this block. Must be 0 when setting + the EDID. + + + __u32 + blocks + The number of blocks to get or set. Must be less or equal to 256 (the + maximum number of blocks as defined by the standard). When you set the EDID and + blocks is 0, then the EDID is disabled or erased. + + + __u8 * + edid + Pointer to memory that contains the EDID. The minimum size is + blocks * 128. + + + __u32 + reserved[5] + Reserved for future extensions. Applications and drivers must + set the array to zero. + + + +
+ + + + &return-value; + + + + ENODATA + + The EDID data is not available. + + + + E2BIG + + The EDID data you provided is more than the hardware can handle. + + + + + -- cgit v1.3.1