[PATCH v3 00/24] i.MX Media Driver

[Philipp Zabel]

Hi Steve,

On Tue, 2017-02-14 at 18:27 -0800, Steve Longerbeam wrote:
[...]
> >
> > # Provide an EDID to the HDMI source
> > v4l2-ctl -d /dev/v4l-subdev2 --set-edid=file=edid-1080p.hex
> 
> I can probably generate this Intel hex file myself from sysfs
> edid outputs, but for convenience do you mind sending me this
> file? I have a 1080p HDMI source I can plug into the tc358743.

I copied the EDID off of some random 1080p HDMI monitor,
probably using something like:

    xxd -g1 /sys/class/drm/card0-HDMI-A-1/edid | cut -c 9-56

----------8<----------
 00 ff ff ff ff ff ff 00 09 d1 89 78 45 54 00 00
 2a 14 01 03 80 35 1e 78 2e b8 45 a1 59 55 9f 28
 0d 50 54 a5 6b 80 81 c0 81 00 81 80 a9 c0 b3 00
 d1 c0 01 01 01 01 02 3a 80 18 71 38 2d 40 58 2c
 45 00 13 2a 21 00 00 1e 00 00 00 ff 00 4e 41 41
 30 36 32 39 36 53 4c 30 0a 20 00 00 00 fd 00 32
 4c 1e 53 11 00 0a 20 20 20 20 20 20 00 00 00 fc
 00 42 65 6e 51 20 47 4c 32 34 34 30 48 0a 01 18
 02 03 22 f1 4f 90 05 04 03 02 01 11 12 13 14 06
 07 15 16 1f 23 09 07 07 65 03 0c 00 10 00 83 01
 00 00 02 3a 80 18 71 38 2d 40 58 2c 45 00 13 2a
 21 00 00 1f 01 1d 80 18 71 1c 16 20 58 2c 25 00
 13 2a 21 00 00 9f 01 1d 00 72 51 d0 1e 20 6e 28
 55 00 13 2a 21 00 00 1e 8c 0a d0 8a 20 e0 2d 10
 10 3e 96 00 13 2a 21 00 00 18 00 00 00 00 00 00
 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 eb
---------->8----------

> The other problem here is that my version of v4l2-ctl, built from
> master branch of git at github.com:gjasny/v4l-utils.git, does not
> support taking a subdev node:
> 
> root at mx6q:~# v4l2-ctl -d /dev/v4l-subdev15 --get-edid=format=hex
> VIDIOC_QUERYCAP: failed: Inappropriate ioctl for device
> /dev/v4l-subdev15: not a v4l2 node
> 
> Is this something you added yourself, or where can I find this version
> of v4l2-ctrl?

Ah right, I still have no proper fix for that. v4l-ctl bails out if it
can't VIDIOC_QUERYCAP, which is an ioctl not supported on subdevices.
I have just patched it out locally:

----------8<----------
diff --git a/utils/v4l2-ctl/v4l2-ctl.cpp b/utils/v4l2-ctl/v4l2-ctl.cpp
index 886a91d093ae..fa15a49375ae 100644
--- a/utils/v4l2-ctl/v4l2-ctl.cpp
+++ b/utils/v4l2-ctl/v4l2-ctl.cpp
@@ -1214,10 +1214,7 @@ int main(int argc, char **argv)
 	}
 
 	verbose = options[OptVerbose];
-	if (doioctl(fd, VIDIOC_QUERYCAP, &vcap)) {
-		fprintf(stderr, "%s: not a v4l2 node\n", device);
-		exit(1);
-	}
+	doioctl(fd, VIDIOC_QUERYCAP, &vcap);
 	capabilities = vcap.capabilities;
 	if (capabilities & V4L2_CAP_DEVICE_CAPS)
 		capabilities = vcap.device_caps;
---------->8----------

Note that setting the EDID is not necessary if you can force the mode on
your HDMI source.

regards
Philipp