ES9038 I2C Linux Driver Install Manual

Setup compile environment

Getting Kernel Source

Install "rpi-source" software.
The "rpi-source" command automaticaly downloads the kernel source that matched running linux kernel version.

https://github.com/notro/rpi-source/wiki

to install:

sudo wget https://raw.githubusercontent.com/notro/rpi-source/master/rpi-source -O /usr/bin/rpi-source && sudo chmod +x /usr/bin/rpi-source && /usr/bin/rpi-source -q --tag-update

Getting dtc (Device Tree Compiler) package

Install dtc by package system.

sudo apt-get install device-tree-compiler 

Install bc command

If bc is not installed, must install bc.

sudo apt-get install bc

Getting GCC package

The GCC version must match the gcc that used to build the kernel, the required version can be checked by

sudo cat /proc/version	

Install GCC-4.9.x by package system.

sudo apt-get install gcc-4.9 g++-4.9

Change default GCC

update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.9 10
update-alternatives --config gcc

Check GCC version is 4.9.x.

gcc --version

Driver Install

1. Get the kernel source

Choose place of kernel source files & directory, e.g. '.' current folder.

rpi-source -d .

if rpi-source gives kernel version mismatch, use

sudo apt-get install raspberrypi-kernel-headers

2. Build & Install driver & dtb (device tree blob)

make
sudo make modules_install
make dtbs
sudo make install_dtbo

3. Change /boot/config.txt

remove existing dtoverlay Add following lines.

dtoverlay=hifibunny3-q2m
dtparam=i2c_arm=on

4. Reboot Raspberry Pi

5. Check driver is normaly installed

Use aplay -l command to check audio card is added.

aplay -l

6. optional: enable bbr

sudo nano /etc/sysctl.conf

add following to the end of the file:

net.core.default_qdisc=fq
net.ipv4.tcp_congestion_control=bbr

In terminal, run:

sudo sysctl -p

check:

sysctl net.ipv4.tcp_congestion_control

Note

This driver only works with the ES9038Q2M DAC connected through i2c/i2s.

Supports volume control and DoP, tested on Moode Audio. SoX resampling needs to be set to '32 bit/ *kHz' for proper DoP function.

DAC is setup in MASTER mode with NCO to support both 44.1KHz and 48KHz family with a single crystal.

Crystal freq is assumed to be 100MHz, if other freq are used, ES9038Q2M_NCO_0~ES9038Q2M_NCO_3 values need to be adjusted.

ES9038Q2M datasheet can be found at http://file2.dzsc.com/product/18/05/25/829029_170233543.pdf (I do not manage this site).