how to enable mic linein input using microphone(3.5mm jack) in UBUNTU

meche95

Hi Firefly team,

I would like to use microphone linein (headset with 3.5mm 4 pin jack) in ubuntu.
I checked the mic is working within Android which is default installation when I got the board first time with change in audio setting in Android.

After the firmware changed to ubuntu 18.04,
I tested the mic device input and checked that is working well which is attached mic sensor device right beside the PWR button.
But I want to use the headset (mic+ spk via 3.5mm jack with 4 pins ).

#01. Is it possible to use

headset  in Ubuntu 18.04 ?

#02. How to disable built-in MIC device in kernel?

I checked that the headset(

mic+ spk via 3.5mm jack with 4 pins)

is working within the Android 7.1 firmware.

#02. Is there a way to use headset in Ubuntu 18.04? (by modifying the kernel & some sound related code)

Or where do I change the kernel code?
Roughly I guess that refer to Android code and change the Ubuntu source tree.


Please give me any information, it will be helpful & appreciated.

penguin

Hi, @meche95,
According to the driver code at:
https://github.com/FireflyTeam/k ... soc/codecs/rt5640.c

add "linein-mute = 1" to the rt5640 node in dts.

Then a "/sys/linein/linein" file will be created.

echo 1 > /sys/linein/linein

should be sufficient to turn on Line In support.

meche95

Hi thank you for reply.
I added the "linein-mute=1" and I found the /sys/linein/linein after compile & flasing the firmware.

But when I install ubuntu using the following guideline, mic input DOES NOT work.
And also linein input does not work.

I'm using the rootfs image named in 'rk3399_ubuntu18.04_LXDE.img'.
http://wiki.t-firefly.com/en/Fir ... ux_compile_gpt.html


When I flash the image (FIREFLY-RK3399-UBUNTU18.04-GPT-20190216-1136.img), then MIC input works well.

But when I compiled the kernel, uboot, etc and using rk3399_ubuntu18.04_LXDE.img rootfs then MIC input did NOT work.
How can I enable Mic input with kernel compile with latest source ?

penguin

Hi @meche95,

You can use some tools to extract FIREFLY-RK3399-UBUNTU18.04-GPT-20190216-1136.img,
splitting into individual kernel, uboot and rootfs image etc.

http://wiki.t-firefly.com/en/Fir ... droid_firmware.html

Then you can take the right rootfs to move on.