I'm trying to use the hdmi cec tools that come with the latest Raspian. When I try and run cec-ctl or cec-compliance I get a fail to open /dev/cec0. The kernel modules I have from lsmod (partial):
videobuf2_dma_contig 20480 1 bcm2835_codec
videobuf2_vmalloc 16384 1 bcm2835_v4l2
videobuf2_memops 16384 2 videobuf2_dma_contig,videobuf2_vmalloc
videobuf2_v4l2 24576 3 bcm2835_codec,bcm2835_v4l2,v4l2_mem2mem
snd_pcm 102400 1 snd_bcm2835
snd_timer 32768 1 snd_pcm
videobuf2_common 45056 4 bcm2835_codec,bcm2835_v4l2,v4l2_mem2mem,videobuf2_v4l2
snd 73728 5 snd_timer,snd_bcm2835,snd_pcm
videodev 200704 6 bcm2835_codec,v4l2_common,videobuf2_common,bcm2835_v4l2,v4l2_mem2mem,videobuf2_v4l2
media 36864 2 videodev,v4l2_mem2mem
What module/driver do I need for the v4l utils?
cec-client -mdo? I'm working on the same problem on my Pi, but that command is able to autodetect and do some things. Once it's running, send the pi CEC commands and it will print it on the screen