Kernel compilation failed (configuration multimedia support on module instead of builded in)

[VivienLaure]

Hi,

I wanted to change a little bit the configuration of the kernel so that i can use a camera with my BPI-R2.

My setup is particular since i use a grabber (the Magewell USB Capture HDMI Gen 2) and a camera plugged in hdmi to this grabber. Finally the camera should be seen as an usb camera device.

The setup is working on my ubuntu 16.04 (kernel 4.13.0-39-generic), i use uvc and v4l and i can display the camera flux using qv4l2 for example.

I tried to configure the kernel so that i have the same modules i use on my desktop version. To do so i had to configure MEDIA_CAMERA_SUPPORT = y, MEDIA_USB_SUPPORT = y and USB_VIDEO_CLASS = m.

The list of module i need :

Module Size Used by
snd_usb_audio 196608 1
snd_usbmidi_lib 32768 1 snd_usb_audio
uvcvideo 90112 0
videobuf2_vmalloc 16384 1 uvcvideo
videobuf2_memops 16384 1 videobuf2_vmalloc
videobuf2_v4l2 24576 1 uvcvideo
videobuf2_core 40960 2 uvcvideo,videobuf2_v4l2

videodev 176128 3 uvcvideo,videobuf2_core,videobuf2_v4l2
media 40960 2 uvcvideo,videodev

The two module i'm missing are media.ko and videodev.ko but when i set MEDIA_SUPPORT = m , i got the following error at the compilation (see attached file). I don't understand this error because i found the definition of the functions marked as undefined references in linux-mt/include/media/cec.h.

I don't know if i'm missing dependencies or if it's a bug because i'm pretty new to that stuff, a little help would be appreciated.

If you need futher information don't hesitate.

Vivien LAURE

Error_log.txt