XU4 HDMI CEC issue

Good idea. At least we should add it to the docs: https://dietpi.com/docs/hardware/
I was thinking to remove the text part from the download page, which seems obsolete when someone already has the board and is now about to download an image for it? I doubt that someone reads the SBC details from our download page to then do a decision about which SBC to obtain?
Then we have some space to fill with information dedicated/relevant for our particular images, like the kernel/repository/pre-image they are shipped with, and/or a link to the docs hardware section. Even that hardware information above the download links seems not that relevant to me there, but a link to the official Wiki/docs/hardware info would be probably more reasonable?

sounds like a good idea, at least we could try to build groups for RPi, Ordoid Rock + x68. So we don’t need to maintain it for each board individually?

Like this: https://github.com/MichaIng/DietPi-Docs/issues/365

Jep, at least the kernel/firmware repository and package maintainers could be grouped as well.

So, lets try reconfiguring kernel:

apt install gcc make libc-dev libncurses-dev bison flex bc build-essential libssl-dev fakeroot git
mkdir kernel
cd kernel
git clone https://github.com/hardkernel/linux.git
cd linux
git checkout -t remotes/origin/odroidxu4-4.14.y
cp /boot/config-4.14.180+ .config
make menuconfig # device drivers -> Multimedia support -> HDMI CEC RC integration
make -j4 deb-pkg LOCALVERSION=-falcot KDEB_PKGVERSION=$(make kernelversion)-1
cd ..
dpkg -i *.deb
cd ..
reboot

After reboot lets check the results:

root@DietPi:~# uname -a
Linux DietPi 4.14.180-falcot #1 SMP PREEMPT Sat Feb 20 14:57:40 GMT 2021 armv7l GNU/Linux

root@DietPi:~# dmesg | grep -i cec
[    3.482080] Registered IR keymap rc-cec
[    3.484638] rc rc0: RC for s5p-cec as /devices/platform/soc/101b0000.cec/rc/rc0
[    3.491962] input: RC for s5p-cec as /devices/platform/soc/101b0000.cec/rc/rc0/input0

But cec-client still gives us no devices:

root@DietPi:~# cec-client -l
libCEC version: 4.0.4, compiled on Linux-4.9.0-8-armmp-lpae ... , features: P8_USB, DRM, P8_detect, randr, Exynos, AOCEC
Found devices: NONE

So, still stuck.

How about checking with cec tools?

apt install v4l-utils
root@DietPi:~# cec-ctl -d0 --playback --phys-addr 4.0.0.0
The CEC adapter doesn't allow setting the physical address manually, ignore this option.

Driver Info:
	Driver Name                : s5p-cec
	Adapter Name               : s5p-cec
	Capabilities               : 0x0000005e
		Logical Addresses
		Transmit
		Passthrough
		Remote Control Support
		Needs HPD
	Driver version             : 4.14.180
	Available Logical Addresses: 1
	Physical Address           : f.f.f.f
	Logical Address Mask       : 0x0000
	CEC Version                : 2.0
	Vendor ID                  : 0x000c03 (HDMI)
	OSD Name                   : Playback
	Logical Addresses          : 1 (Allow RC Passthrough)

	  Logical Address          : Not Allocated
	    Primary Device Type    : Playback
	    Logical Address Type   : Playback
	    All Device Types       : Playback
	    RC TV Profile          : None
	    Device Features        :
		None

root@DietPi:~# cec-follower -d0 &
cec-follower SHA                   : not available

Driver Info:
	Driver Name                : s5p-cec
	Adapter Name               : s5p-cec
	Capabilities               : 0x0000005e
		Logical Addresses
		Transmit
		Passthrough
		Remote Control Support
		Needs HPD
	Driver version             : 4.14.180
	Available Logical Addresses: 1
	Physical Address           : f.f.f.f
	Logical Address Mask       : 0x0000
	CEC Version                : 2.0
	Vendor ID                  : 0x000c03 (HDMI)
	OSD Name                   : Playback
	Logical Addresses          : 1 (Allow RC Passthrough)

	  Logical Address          : Not Allocated
	    Primary Device Type    : Playback
	    Logical Address Type   : Playback
	    All Device Types       : Playback
	    RC TV Profile          : None
	    Device Features        :
		None

Initial Event: State Change: PA: f.f.f.f, LA mask: 0x0000

root@DietPi:~# cec-compliance -d0 -r0
cec-compliance SHA                 : not available
Driver Info:
	Driver Name                : s5p-cec
	Adapter Name               : s5p-cec
	Capabilities               : 0x0000005e
		Logical Addresses
		Transmit
		Passthrough
		Remote Control Support
		Needs HPD
	Driver version             : 4.14.180
	Available Logical Addresses: 1
	Physical Address           : f.f.f.f
	Logical Address Mask       : 0x0000
	CEC Version                : 2.0
	Vendor ID                  : 0x000c03 (HDMI)
	OSD Name                   : Playback
	Logical Addresses          : 1 (Allow RC Passthrough)

	  Logical Address          : Not Allocated
	    Primary Device Type    : Playback
	    Logical Address Type   : Playback
	    All Device Types       : Playback
	    RC TV Profile          : None
	    Device Features        :
		None

Compliance test for device /dev/cec0:

    The test results mean the following:
        OK                  Supported correctly by the device.
        OK (Not Supported)  Not supported and not mandatory for the device.
        OK (Presumed)       Presumably supported.  Manually check to confirm.
        OK (Unexpected)     Supported correctly but is not expected to be supported for this device.
        OK (Refused)        Supported by the device, but was refused.
        FAIL                Failed and was expected to be supported by this device.

Find remote devices:
		fail: cec-compliance.cpp(886): doioctl(node, CEC_TRANSMIT, &msg)
	Polling: FAIL

Network topology:

Total: 1, Succeeded: 0, Failed: 1, Warnings: 0

Meaning still no actual progress

Created a topic on the Hardkernel forum: https://forum.odroid.com/viewtopic.php?f=96&t=41886