Module does not build

[jkanev]

When compiling for the latest kernel, the compiler stops with an error. From /var/lib/dkms/akvcam/1.2.3/build/make.log:

DKMS (dkms-3.2.0) make.log for akvcam/1.2.3 for kernel 6.12.38+deb13-amd64 (x86_64)
Wed 20 Aug 13:36:18 CEST 2025

Building module(s)
# command: make -j4 KERNELRELEASE=6.12.38+deb13-amd64 KERNEL_DIR=/lib/modules/6.12.38+deb13-amd64/build all
make -C /lib/modules/6.12.38+deb13-amd64/build M=/var/lib/dkms/akvcam/1.2.3/build  modules
make[1]: Entering directory '/usr/src/linux-headers-6.12.38+deb13-amd64'
  CC [M]  /var/lib/dkms/akvcam/1.2.3/build/module.o
  CC [M]  /var/lib/dkms/akvcam/1.2.3/build/attributes.o
  CC [M]  /var/lib/dkms/akvcam/1.2.3/build/buffers.o
  CC [M]  /var/lib/dkms/akvcam/1.2.3/build/controls.o
  CC [M]  /var/lib/dkms/akvcam/1.2.3/build/device.o
  CC [M]  /var/lib/dkms/akvcam/1.2.3/build/driver.o
/var/lib/dkms/akvcam/1.2.3/build/buffers.c: In function ‘akvcam_buffers_new’:
/var/lib/dkms/akvcam/1.2.3/build/buffers.c:107:16: error: ‘struct vb2_queue’ has no member named ‘min_buffers_needed’
  107 |     self->queue.min_buffers_needed = AKVCAM_BUFFERS_MIN;
      |                ^
/var/lib/dkms/akvcam/1.2.3/build/buffers.c: In function ‘akvcam_buffers_count’:
/var/lib/dkms/akvcam/1.2.3/build/buffers.c:145:23: error: ‘const struct vb2_queue’ has no member named ‘min_buffers_needed’
  145 |     return self->queue.min_buffers_needed;
      |                       ^
/var/lib/dkms/akvcam/1.2.3/build/buffers.c: In function ‘akvcam_buffers_set_count’:
/var/lib/dkms/akvcam/1.2.3/build/buffers.c:150:16: error: ‘struct vb2_queue’ has no member named ‘min_buffers_needed’
  150 |     self->queue.min_buffers_needed = nbuffers;
      |                ^
/var/lib/dkms/akvcam/1.2.3/build/buffers.c: In function ‘akvcam_buffers_count’:
/var/lib/dkms/akvcam/1.2.3/build/buffers.c:146:1: error: control reaches end of non-void function [-Werror=return-type]
  146 | }
      | ^
cc1: some warnings being treated as errors
make[3]: *** [/usr/src/linux-headers-6.12.38+deb13-common/scripts/Makefile.build:234: /var/lib/dkms/akvcam/1.2.3/build/buffers.o] Error 1
make[3]: *** Waiting for unfinished jobs....
/var/lib/dkms/akvcam/1.2.3/build/device.c: In function ‘akvcam_device_new’:
/var/lib/dkms/akvcam/1.2.3/build/device.c:133:14: error: ‘V4L2_DEVICE_NAME_SIZE’ undeclared (first use in this function)
  133 |              V4L2_DEVICE_NAME_SIZE,
      |              ^~~~~~~~~~~~~~~~~~~~~
/var/lib/dkms/akvcam/1.2.3/build/device.c:133:14: note: each undeclared identifier is reported only once for each function it appears in
make[3]: *** [/usr/src/linux-headers-6.12.38+deb13-common/scripts/Makefile.build:234: /var/lib/dkms/akvcam/1.2.3/build/device.o] Error 1
make[2]: *** [/usr/src/linux-headers-6.12.38+deb13-common/Makefile:1970: /var/lib/dkms/akvcam/1.2.3/build] Error 2
make[1]: *** [/usr/src/linux-headers-6.12.38+deb13-common/Makefile:236: __sub-make] Error 2
make[1]: Leaving directory '/usr/src/linux-headers-6.12.38+deb13-amd64'
make: *** [Makefile:44: all] Error 2

# exit code: 2
# elapsed time: 00:00:03
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