v4l2 control ops can not be called by v4l2-ctl

[Kyletec]

Hi

I am using imx8mm to develop a camera driver.

System is debian buster kernel version 4.19.35

I am currently using default OV5640 camera with the driver ov5640_mipi_v2.c under /drivers/media/platform/mxc/capture. The basic functions works well with clear video. 

Then I need to add some control functions such as V4L2_CID_EXPOSURE and V4L2_CID_CONTRAST. I wrote ov5640_ctrl_ops and related functions according to https://www.kernel.org/doc/html/v4.19/media/kapi/v4l2-controls.html

But I cannot call the ctrls by v4l2-ctl command.

When i try "v4l2-ctl -d /dev/video0 -c Exposure=0" it shows "unknown control". 

"v4l2-ctl --list-ctrls --device /dev/video0" shows nothing.

I checked i.MX Reference Manual but the document seems not updated and gave no clue about imx8 board

Am I missing some modules in the kernel? Or using wrong library? 

Does anyone can help?

Thanks in advance and best regards,

Kai

[igorpadykov]

Hi Kai 

what bsp used in the case, may be recommended to try latest nxp releases from

source.codeaurora.org/external/imx/linux-imx repository
https://source.codeaurora.org/external/imx/linux-imx/tree/?h=lf-5.10.y

Documentation:

https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applicat...

Best regards
igor

[Kyletec]

Hello Igor,

Thank you for your reply. I am currently using BSP version 4.19.35

https://source.codeaurora.org/external/imx/linux-imx/tree/?h=imx_4.19.35_1.1.0

Does this version support any v4l2 control options? Or I must update to higher version?

Best regards,

Kai

[igorpadykov]

for "v4l2-ctl" efforts may be useful to look on below

https://community.nxp.com/t5/i-MX-Processors/Unable-to-record-a-video-using-MINISASTOCSI/td-p/128538...

Best regards
igor