Manjaro + Kodi + LG TV: CEC not working at all

[naps62]

I have an LG C1 tv, a Raspberry Pi 4B on which I installed Manjaro and Kodi

On Kodi's settings, CEC does not even show as an option (in previous attempts that I had before settling on Manjaro, there was an option on Input -> Peripherals, even though I never got it to work)

I have installed kodi-rpi, which depends on libcec-rpi

cec-client gives me the following output (while connected to the TV):

naps62 in pi in ~
❯ cec-client -l
libCEC version: 6.0.2, git revision: <unknown>, compiled on 2021-03-27 18:45:45 by ray@pi4 on Linux 5.10.25-2-MANJARO-ARM (aarch64), features: P8_USB, DRM, P8_detect, randr, Linux
Found devices: NONE

I've tried a couple of different HDMI cables, tried all 4 of the tv's input ports, and tried disconnecting other HDMI devices (as I saw in another thread). Kodi's debug logs have no mention of CEC at all

I'm running out of ideas, and need help

[naps62]

Apparently changing the PKGBUILD of libcec-rpi to include -DRPI_INCLUDE_DIR=/opt/vc/include -DRPI_LIB_DIR=/opt/vc/lib seems to fix it on libcec's side (still testing Kodi)

can anyone confirm if this is an appropiate fix? in which case I guess the published pkgbuild is wrong (which I know is not this repo's responsibility)

[popcornmix]

If you want to build cec to use the firmware cec driver then those defines are needed: https://github.com/Pulse-Eight/libcec/blob/master/docs/README.raspberrypi.md

When using the linux driver for cec (i.e. using dtoverlay=vc4-kms-v3d), those options aren't needed.

[naps62]

I'm not sure what your first sentence means, to be honest. I'm not very familiar with how these libraries work

Are you saying the PKGBUILD from libcec-rpi is indeed wrong? (given that it's intended to target Raspberry Pi)

[popcornmix]

I think these are questions for Manjaro.

I'm just saying you can build libcec for the rpi firmware cec driver using instructions here. Or you can build it using the linux cec framework (available when using dtoverlay=vc4-kms-v3d) by following instructions here.

I don't know know which Manjaro considers the default.

[naps62]

manjaro uses no defaults. It just compiles from this file, which defines the flags in the build() function explicitly

Indeed, I have dtoverlay=vc4-fkms-v3d on my system (added by kodi I believe?). Would this cause the compilation to run with Raspberry pi support: NO? (which is what was happening) Or should it still say YES in that case?

[PanopticaRising]

Thanks @naps62 for opening this thread, I recently set up a RPI4 with Manjaro and was banging my head against a wall, and thanks @popcornmix for the instructions.

I had compiled libcec myself to troubleshoot the issue, but I missed the key line:

-- Raspberry Pi support:                   yes
-- Linux support:                          yes

Even though I have dtoverlay=vc4-fkms-v3d, I still needed to add the RPI lib/include directories in /opt/vc for RPI support to show up. I recompiled with both,

cmake -DHAVE_LINUX_API=1  -DRPI_INCLUDE_DIR=/opt/vc/include -DRPI_LIB_DIR=/opt/vc/lib ..

And my cec-client finally detects my LG TV!

Looking at the PKGBUILD that @naps62 posted, I'd wager the similar missing RPIINCLUDE* is the source of the problem.

[PanopticaRising]

Correction, that PKGBUILD file had the RPI_INCLUDE_ options included in a previous commit. The maintainers removed it, referencing this in the commit: https://github.com/raspberrypi/linux/issues/4103