topic Re: VIDIOC_DBG_G_CHIP_IDENT failed in i.MX Processors

VIDIOC_DBG_G_CHIP_IDENT failed

dh29 — Tue, 19 Jun 2018 14:49:48 GMT

I am trying to interface an AD7280M (MIPI) video grabber to an IMX7D. I have managed to get the driver initializing the ADV7280M on boot, but upon trying to perform any capture (imx-test utils) I get a VIDIOC_DBG_G_CHIP_IDENT error.

I have the ADV7280M configured in progressive test mode (non-interlaced).

If I run v4l2-dbg -l then I get:

ioctl: VIDIOC_DBG_G_REGISTER

00 04 08 0C 10 14 18 1C
ioctl: VIDIOC_DBG_G_REGISTER failed
: Inappropriate ioctl for device
00000000:

Within my driver, ioctl_dev_init() is never being called, but I don't understand what part of Linux should be calling this?

Is the VIDIOC_DBG_G_CHIP_IDENT error as a result of ioctl_dev_init() not being called?

Is ioctl_dev_init() not being called because of the cause of the VIDIOC_DBG_G_CHIP_IDENT error?

Any guidance/explanation would be appreciated.

Re: VIDIOC_DBG_G_CHIP_IDENT failed

jamesbone — Thu, 05 Jul 2018 14:32:54 GMT

Hello Dh29,

VIDIOC_DBG_G_CHIP_IDENT allows the camera driver to identify itself. Most likely you are not compiling the camera driver or modprobing it. Which camera are you using?

Re: VIDIOC_DBG_G_CHIP_IDENT failed

dh29 — Fri, 06 Jul 2018 16:51:16 GMT

Hi jamesbone ,

Thanks for your reply. It is actually my own driver for an ADV7820M, that is based on /drivers/media/platform/mxc/subdev/ov5640_mipi.c.

The driver is definitely being probed. I am able to capture video using a PAL camera, via the ADV7820M, using gstreamer-1.0.