With linux-rpi 5.15.23-1 kernel, Hifiberry DAC2 HD fails

I've been tinkering with this all day. I have a Raspberry Pi 4B with Arch Linux installed. I have a Hifiberry DAC2 HD, and with kernel 5.15.23, I cannot get the DAC2 HD to initialize.

My config.txt is:

$this->bbcode_second_pass_quote('', 'g')pu_mem=32
initramfs initramfs-linux.img followkernel
max_usb_current=1
disable_splash=1
disable_overscan=1
dtparam=krnbt=on
dtparam=i2s=on
force_eeprom_read=0
dtoverlay=hifiberry-dacplushd

[graysky]

I believe we are shipping modules for all hifiberry stuff offered in the kernel. I did not see one specifically named "DAC2" though. Can you point me to a reference document spelling out which modules are needed for this hardware?
$this->bbcode_second_pass_code('', '
Location:
-> Device Drivers
-> Sound card support (SOUND [=y])
-> Advanced Linux Sound Architecture (SND [=m])
-> ALSA for SoC audio support (SND_SOC [=m])
...
<M> Support for HifiBerry DAC
<M> Support for HifiBerry DAC+
<M> Support for HifiBerry DAC+ HD
<M> Support for HifiBerry DAC+ADC
<M> Support for HifiBerry DAC+ADC PRO
<M> Support for HifiBerry DAC+DSP
<M> Support for HifiBerry Digi
<M> Support for the HifiBerry Amp
...
')

[apastuszak]

Hifiberry's documentation says to use DAC+ HD:

https://www.hifiberry.com/blog/configur ... linux-5-4/

https://www.hifiberry.com/docs/software ... ux-3-18-x/

This does work in the 5.10 kernel.

[graysky]

Please consider opening a ticket upsteam if you believe the hardware worked under rpi-5.10.y but not under rpi-5.15.y: https://github.com/raspberrypi/linux/issues/new/choose

[apastuszak]

I installed Raspbian and used rpi-update to install the 5.15 kernel and the DAC 2 HD disappeared from the aplay list.

I opened an upstream bug.

https://github.com/raspberrypi/linux/issues/4898

Feel freed to review and tell me if I need to provide them with any additional details.

[graysky]

If you can confirm the bug on RPiOS + ArchARM, it is clearly upstream

[graysky]

https://github.com/raspberrypi/linux/co ... 1d66d9c179

[apastuszak]

I saw that this morning. Now we just need to wait for it to trickle down. Impressive, they got it done so quickly.

[graysky]

$this->bbcode_second_pass_quote('apastuszak', 'I') saw that this morning. Now we just need to wait for it to trickle down. Impressive, they got it done so quickly.

[apastuszak]

I manually updated the overlay and it worked, once I I added the overlay to my config.txt.

In 5.10, the kernel automatically detected it and it just worked. In 5.15, I have to add:

$this->bbcode_second_pass_code('', 'force_eeprom_read=0
dtoverlay=hifiberry-dacplushd')

Then I reboot and the DAC2HD works.