Hello community,

 

I am running Armbian taken from here on Radxa Rock 4c+. Everything I need seems to be in order (including wifi) but there appears to be no bluetooth device present (it is there using Radxa's images which have old kernels though).

I tried to find out what could be the reason and noticed that dtb coming with Radxa has this:

 

		wireless-bluetooth {

			uart0-gpios {
				rockchip,pins = <0x02 0x13 0x00 0xd0>;
				phandle = <0xf1>;
			};
		};

 in pincntrl section and few other bluetooth/uart related bits while one coming with Armbian does not.

 

I am not sure if this is the root cause and what the easiest way to fix it. I would appreciate any pointers on how to make bluetooth work.

 

Thanks

Edited January 22, 20233 yr by Vskho

Just to leave a note for someone who would come across

 

As I suspected, the issue was in device tree configuration. I checked DTS files for the rock 4c+ in the corresponding release tag of the mainline kernel source (6.1 in my case), and saw that it had bluetooth config present, similar to Radxa's own kernels. I could not find where does Armbian take their DTSes from.

 

Anyway, things I did:

1. Followed regular steps for building the kernel. To be safe, I went with version of the sources as close to the running kernel version as possible.
2. Built just device tree blobs with `make dbts` in the root of sources.
3. Copied over the generated file (arch/arm64/boot/dts/rockchip/rk3399-rock-4c-plus.dtb) to /boot/dtbs
4. Updated `/boot/armbianEnv.txt` to point `fdtfile` the blob I just put there.
5. Reboot!

After this I immediately got bluetooth and sound working, I do not experience any issues with BT keyboard connectivity/speed (as I used to with official legacy 4.4 kernel).

 

P.S.: there are though some things that got broken because of the update. Particularly, I cannot seem to be able to enable the thermal sensor ADC anymore, although, it works fine with DTB shipped by default.

Edited January 30, 20233 yr by Vskho

Do you still have a copy of the rk3399-rock-4c-plus.dtb?

@Joeish360 Here is one I use at the moment which has bluetooth, wifi and thermal sensors working:

 

 

rk3399-rock-4c-plus.dtb

Do you have issues with audio output?
My Rock Pi 4C+ does not recognize builtin sound card:
 

root@rockpi-4cplus:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
root@rockpi-4cplus:~#

 

You`re running Kernel 6.1 ?
Did you guys made any changes for the GPU/Driver/Resolution ?
only with a forced resolution in the armbianenv I got videoutput in the CLI & bootime but as soon the xserver started I got no more video output or I got broken output :-S

with kernel 5 I also got a BT issue & I also guess there is an issue with DTB, btw. GPU is disabled by default but easy to fix in the decompiled DTS file.

unfortunately I couldn't follow these steps ...., but does make dtbs the same than compling a DTS to DTB ?
Did you use any specific dts ?

I'm a bit confused because I tried every DTS /DTB I found....

 

@krankes_etwas, yes, I am on 6.1.11 at the moment with DTB compiled from the master branch of linux kernel.

I did not do anything specific with the resolution/graphics, it worked out of box for me.

As far as I know, `make dtbs` compiles dtc and builds dts to dtbs with it.

@Roman Khudobei I think I have the same, however, I've got sound through HDMI screen, that's the only ALSA source pulseaudio displays. Built-in audiojack does not work.

1 source(s) available.
  * index: 0
	name: <alsa_output.platform-hdmi-sound.stereo-fallback.monitor>
	driver: <module-alsa-card.c>
	flags: DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY
	state: SUSPENDED
	suspend cause: IDLE
	priority: 1000
	volume: front-left: 65536 / 100% / 0.00 dB,   front-right: 65536 / 100% / 0.00 dB
	        balance 0.00
	base volume: 65536 / 100% / 0.00 dB
	volume steps: 65537
	muted: no
	current latency: 0.00 ms
	max rewind: 0 KiB
	sample spec: s16le 2ch 44100Hz
	channel map: front-left,front-right
	             Stereo
	used by: 0
	linked by: 0
	configured latency: 0.00 ms; range is 0.50 .. 2000.00 ms
	monitor_of: 0
	card: 0 <alsa_card.platform-hdmi-sound>
	module: 6
	properties:
		device.description = "Monitor of Built-in Audio Stereo"
		device.class = "monitor"
		alsa.card = "0"
		alsa.card_name = "hdmi-sound"
		alsa.long_card_name = "hdmi-sound"
		alsa.driver_name = "snd_soc_simple_card"
		device.bus_path = "platform-hdmi-sound"
		sysfs.path = "/devices/platform/hdmi-sound/sound/card0"
		device.form_factor = "internal"
		device.string = "0"
		module-udev-detect.discovered = "1"
		device.icon_name = "audio-card"