Public bug reported:
Summary
On an ASUS Zenbook S14 UX5406SA (Lunar Lake) running Ubuntu 25.10 beta, the
internal speakers/mic do not work. SOF topology for this model is present
(l23), firmware packages are current, but the cs42l43 codec and cs35l56
amplifiers fail to initialize due to missing power supplies (kernel falls back
to “dummy regulator”). Likely a kernel/platform (ACPI/regulator mapping) issue
rather than SOF firmware.
System
Device: ASUS Zenbook S14 UX5406SA (Lunar Lake)
Ubuntu: 25.10 beta (Questing)
Kernel: 6.17.0-4-generic (uname -a: Linux ubuntu 6.17.0-4-generic
#4-Ubuntu SMP PREEMPT_DYNAMIC Mon Sep 8 16:09:17 UTC 2025 x86_64
GNU/Linux)
Firmware/UCm:
firmware-sof-signed 2025.05.1-1 (installed & candidate)
alsa-ucm-conf 1.2.12-1ubuntu2
Topology files present (excerpt):
/lib/firmware/intel/sof-ipc4-tplg/
sof-lnl-cs42l43-l0-cs35l56-l23-2ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23-4ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23.tplg
ALSA Card:
0 [sofsoundwire]: sof-soundwire - sof-soundwire
ASUSTeKCOMPUTERINC.-ASUSZenbookS14UX5406SA_UX5406SA-1.0-UX5406SA
Observed behavior (dmesg excerpts)
sof-audio-pci-intel-lnl ...: SoundWire enabled on CannonLake+ platform, using
SOF driver
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-p not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-d not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-a not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-io not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-cp not found, using dummy regulator
...
cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_P not found, using dummy regulator
cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_IO not found, using dummy regulator
cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_A not found, using dummy regulator
...
cs42l43-codec cs42l43-codec: supply vdd-amp not found, using dummy regulator
...
cs42l43 sdw:0:0:01fa:4243:01: Failed to read IRQ status: -16
What I expected
With current firmware-sof-signed and the correct l23 topology present, the
codec/amps should get proper regulator supplies via ACPI/platform definitions
and initialize, providing working internal speakers/mic.
What I get
Only HDMI/DP sinks appear; internal speakers/mic are non-functional (PipeWire
shows “Dummy Output”/no sinks). The drivers explicitly warn about missing
supplies and fail to attach properly on SoundWire.
Why I believe this is a kernel/platform issue
SOF firmware and topology files are present and up-to-date.
Errors indicate missing regulator supplies (VDD_P, VDD_A, VDD_IO, etc.)
for cs42l43/cs35l56, which are normally provided via ACPI/regulator
mappings in the platform layer.
Fedora reportedly has this model working already; likely their kernel
carries upstream/backported fixes for Lunar Lake + cs42l43/cs35l56
regulator/ACPI integration.
Request
Please review and pull/backport the upstream fixes that define the required
regulators/mappings for ASUS UX5406SA (Lunar Lake) using cs42l43 + cs35l56 on
SoundWire. If additional UCM tweaks are needed for the l23 variant, please
advise.
Commands used:
uname -a
apt policy firmware-sof-signed alsa-ucm-conf
ls /lib/firmware/intel/sof-ipc4-tplg/ | grep l23
cat /proc/asound/cards
dmesg | grep -i -e snd_sof -e soundwire -e cs42l43 -e cs35l56 | tail -n 200
ubuntu@ubuntu:~$ uname -a
Linux ubuntu 6.17.0-4-generic #4-Ubuntu SMP PREEMPT_DYNAMIC Mon Sep 8 16:09:17
UTC 2025 x86_64 GNU/Linux
ubuntu@ubuntu:~$ apt policy firmware-sof-signed alsa-ucm-conf
firmware-sof-signed:
Installed: 2025.05.1-1
Candidate: 2025.05.1-1
Version table:
*** 2025.05.1-1 500
500 cdrom://Ubuntu 25.10 _Questing Quokka_ - Beta amd64 (20250917.2)
questing/main amd64 Packages
500 cdrom://Ubuntu 25.10 _Questing Quokka_ - Beta amd64 (20250917.2)
questing/main i386 Packages
500 http://archive.ubuntu.com/ubuntu questing/main amd64 Packages
500 http://archive.ubuntu.com/ubuntu questing/main i386 Packages
100 /var/lib/dpkg/status
alsa-ucm-conf:
Installed: 1.2.12-1ubuntu2
Candidate: 1.2.12-1ubuntu2
Version table:
*** 1.2.12-1ubuntu2 500
500 http://archive.ubuntu.com/ubuntu questing/main amd64 Packages
500 http://archive.ubuntu.com/ubuntu questing/main i386 Packages
100 /var/lib/dpkg/status
ubuntu@ubuntu:~$ ls /lib/firmware/intel/sof-ipc4-tplg/ | grep l23
sof-adl-cs42l43-l0-cs35l56-l23.tplg
sof-arl-cs42l43-l0-cs35l56-l23.tplg
sof-lnl-cs42l43-l0-cs35l56-l23-2ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23-4ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23.tplg
sof-lnl-rt711-l0-rt1316-l23-rt714-l1.tplg
sof-mtl-cs42l43-l0-cs35l56-l23.tplg
sof-mtl-rt711-l0-rt1316-l23-rt714-l1.tplg
ubuntu@ubuntu:~$ cat /proc/asound/cards
0 [sofsoundwire ]: sof-soundwire - sof-soundwire
ASUSTeKCOMPUTERINC.-ASUSZenbookS14UX5406SA_UX5406SA-1.0-UX5406SA
ubuntu@ubuntu:~$
sudo dmesg | grep -i -e snd_sof -e soundwire -e cs42l43 -e cs35l56 | tail -n 200
[ 10.413856] sof-audio-pci-intel-lnl 0000:00:1f.3: SoundWire enabled on
CannonLake+ platform, using SOF driver
[ 11.010122] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-p not found, using
dummy regulator
[ 11.010225] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-d not found, using
dummy regulator
[ 11.010250] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-a not found, using
dummy regulator
[ 11.010263] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-io not found, using
dummy regulator
[ 11.010279] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-cp not found, using
dummy regulator
[ 11.015735] cs42l43 sdw:0:0:01fa:4243:01: devid: 0x042a43, rev: 0xa1, otp:
0x03
[ 11.046810] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_P not found, using
dummy regulator
[ 11.046865] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_IO not found, using
dummy regulator
[ 11.046875] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_A not found, using
dummy regulator
[ 11.054838] cs35l56 sdw:0:2:01fa:3556:01:0: Cirrus Logic CS35L56 Rev B0 OTP3
fw:3.4.4 (patched=0)
[ 11.062578] cs35l56 sdw:0:2:01fa:3556:01:0: Slave 2 state check1:
UNATTACHED, status was 1
[ 11.062778] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_P not found, using
dummy regulator
[ 11.062831] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_IO not found, using
dummy regulator
[ 11.062846] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_A not found, using
dummy regulator
[ 11.070812] cs35l56 sdw:0:2:01fa:3556:01:1: Cirrus Logic CS35L56 Rev B0 OTP3
fw:3.4.4 (patched=0)
[ 11.072524] sof-audio-pci-intel-lnl 0000:00:1f.3: Topology file:
intel/sof-ipc4-tplg/sof-lnl-cs42l43-l0-cs35l56-l23-2ch.tplg
[ 11.078035] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_P not found, using
dummy regulator
[ 11.078066] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_IO not found, using
dummy regulator
[ 11.078071] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_A not found, using
dummy regulator
[ 11.085803] cs35l56 sdw:0:3:01fa:3556:01:2: Cirrus Logic CS35L56 Rev B0 OTP3
fw:3.4.4 (patched=0)
[ 11.085911] cs35l56 sdw:0:2:01fa:3556:01:1: Slave 1 state check1:
UNATTACHED, status was 1
[ 11.089553] cs42l43 sdw:0:0:01fa:4243:01: Slave 6 state check1: UNATTACHED,
status was 1
[ 11.092655] cs35l56 sdw:0:3:01fa:3556:01:2: Slave 2 state check1:
UNATTACHED, status was 1
[ 11.092663] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_P not found, using
dummy regulator
[ 11.092683] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_IO not found, using
dummy regulator
[ 11.092688] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_A not found, using
dummy regulator
[ 11.099500] cs35l56 sdw:0:3:01fa:3556:01:3: Cirrus Logic CS35L56 Rev B0 OTP3
fw:3.4.4 (patched=0)
[ 11.110428] cs35l56 sdw:0:3:01fa:3556:01:3: Slave 1 state check1:
UNATTACHED, status was 1
[ 11.706761] cs42l43-codec cs42l43-codec: supply vdd-amp not found, using
dummy regulator
[ 11.735217] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_B not found, using
dummy regulator
[ 11.735235] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_AMP not found, using
dummy regulator
[ 11.737319] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_B not found, using
dummy regulator
[ 11.737344] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_AMP not found, using
dummy regulator
[ 11.740916] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_B not found, using
dummy regulator
[ 11.740927] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_AMP not found, using
dummy regulator
[ 11.743148] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_B not found, using
dummy regulator
[ 11.743179] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_AMP not found, using
dummy regulator
[ 11.752570] cs35l56 sdw:0:3:01fa:3556:01:3: DSP1:
cirrus/cs35l56-b0-dsp1-misc-10431e13.wmfw: format 3 timestamp 0x65e6703c
** Affects: linux (Ubuntu)
Importance: Undecided
Status: New
** Tags: asus audio cs35l56 cs42l43 lunar-lake sof soundwire zenbook
** Attachment added: "Screenshot From 2025-09-21 08-00-16.png"
https://bugs.launchpad.net/bugs/2125284/+attachment/5910753/+files/Screenshot%20From%202025-09-21%2008-00-16.png
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https://bugs.launchpad.net/bugs/2125284
Title:
ASUS Zenbook S14 UX5406SA (Lunar Lake): no internal audio –
cs42l43/cs35l56 report missing power supplies (“using dummy
regulator”) on Ubuntu 25.10 beta (kernel 6.17)
Status in linux package in Ubuntu:
New
Bug description:
Summary
On an ASUS Zenbook S14 UX5406SA (Lunar Lake) running Ubuntu 25.10 beta, the
internal speakers/mic do not work. SOF topology for this model is present
(l23), firmware packages are current, but the cs42l43 codec and cs35l56
amplifiers fail to initialize due to missing power supplies (kernel falls back
to “dummy regulator”). Likely a kernel/platform (ACPI/regulator mapping) issue
rather than SOF firmware.
System
Device: ASUS Zenbook S14 UX5406SA (Lunar Lake)
Ubuntu: 25.10 beta (Questing)
Kernel: 6.17.0-4-generic (uname -a: Linux ubuntu 6.17.0-4-generic
#4-Ubuntu SMP PREEMPT_DYNAMIC Mon Sep 8 16:09:17 UTC 2025 x86_64
GNU/Linux)
Firmware/UCm:
firmware-sof-signed 2025.05.1-1 (installed & candidate)
alsa-ucm-conf 1.2.12-1ubuntu2
Topology files present (excerpt):
/lib/firmware/intel/sof-ipc4-tplg/
sof-lnl-cs42l43-l0-cs35l56-l23-2ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23-4ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23.tplg
ALSA Card:
0 [sofsoundwire]: sof-soundwire - sof-soundwire
ASUSTeKCOMPUTERINC.-ASUSZenbookS14UX5406SA_UX5406SA-1.0-UX5406SA
Observed behavior (dmesg excerpts)
sof-audio-pci-intel-lnl ...: SoundWire enabled on CannonLake+ platform, using
SOF driver
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-p not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-d not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-a not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-io not found, using dummy regulator
cs42l43 sdw:0:0:01fa:4243:01: supply vdd-cp not found, using dummy regulator
...
cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_P not found, using dummy regulator
cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_IO not found, using dummy regulator
cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_A not found, using dummy regulator
...
cs42l43-codec cs42l43-codec: supply vdd-amp not found, using dummy regulator
...
cs42l43 sdw:0:0:01fa:4243:01: Failed to read IRQ status: -16
What I expected
With current firmware-sof-signed and the correct l23 topology present, the
codec/amps should get proper regulator supplies via ACPI/platform definitions
and initialize, providing working internal speakers/mic.
What I get
Only HDMI/DP sinks appear; internal speakers/mic are non-functional (PipeWire
shows “Dummy Output”/no sinks). The drivers explicitly warn about missing
supplies and fail to attach properly on SoundWire.
Why I believe this is a kernel/platform issue
SOF firmware and topology files are present and up-to-date.
Errors indicate missing regulator supplies (VDD_P, VDD_A, VDD_IO,
etc.) for cs42l43/cs35l56, which are normally provided via
ACPI/regulator mappings in the platform layer.
Fedora reportedly has this model working already; likely their kernel
carries upstream/backported fixes for Lunar Lake + cs42l43/cs35l56
regulator/ACPI integration.
Request
Please review and pull/backport the upstream fixes that define the required
regulators/mappings for ASUS UX5406SA (Lunar Lake) using cs42l43 + cs35l56 on
SoundWire. If additional UCM tweaks are needed for the l23 variant, please
advise.
Commands used:
uname -a
apt policy firmware-sof-signed alsa-ucm-conf
ls /lib/firmware/intel/sof-ipc4-tplg/ | grep l23
cat /proc/asound/cards
dmesg | grep -i -e snd_sof -e soundwire -e cs42l43 -e cs35l56 | tail -n 200
ubuntu@ubuntu:~$ uname -a
Linux ubuntu 6.17.0-4-generic #4-Ubuntu SMP PREEMPT_DYNAMIC Mon Sep 8
16:09:17 UTC 2025 x86_64 GNU/Linux
ubuntu@ubuntu:~$ apt policy firmware-sof-signed alsa-ucm-conf
firmware-sof-signed:
Installed: 2025.05.1-1
Candidate: 2025.05.1-1
Version table:
*** 2025.05.1-1 500
500 cdrom://Ubuntu 25.10 _Questing Quokka_ - Beta amd64 (20250917.2)
questing/main amd64 Packages
500 cdrom://Ubuntu 25.10 _Questing Quokka_ - Beta amd64 (20250917.2)
questing/main i386 Packages
500 http://archive.ubuntu.com/ubuntu questing/main amd64 Packages
500 http://archive.ubuntu.com/ubuntu questing/main i386 Packages
100 /var/lib/dpkg/status
alsa-ucm-conf:
Installed: 1.2.12-1ubuntu2
Candidate: 1.2.12-1ubuntu2
Version table:
*** 1.2.12-1ubuntu2 500
500 http://archive.ubuntu.com/ubuntu questing/main amd64 Packages
500 http://archive.ubuntu.com/ubuntu questing/main i386 Packages
100 /var/lib/dpkg/status
ubuntu@ubuntu:~$ ls /lib/firmware/intel/sof-ipc4-tplg/ | grep l23
sof-adl-cs42l43-l0-cs35l56-l23.tplg
sof-arl-cs42l43-l0-cs35l56-l23.tplg
sof-lnl-cs42l43-l0-cs35l56-l23-2ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23-4ch.tplg
sof-lnl-cs42l43-l0-cs35l56-l23.tplg
sof-lnl-rt711-l0-rt1316-l23-rt714-l1.tplg
sof-mtl-cs42l43-l0-cs35l56-l23.tplg
sof-mtl-rt711-l0-rt1316-l23-rt714-l1.tplg
ubuntu@ubuntu:~$ cat /proc/asound/cards
0 [sofsoundwire ]: sof-soundwire - sof-soundwire
ASUSTeKCOMPUTERINC.-ASUSZenbookS14UX5406SA_UX5406SA-1.0-UX5406SA
ubuntu@ubuntu:~$
sudo dmesg | grep -i -e snd_sof -e soundwire -e cs42l43 -e cs35l56 | tail -n
200
[ 10.413856] sof-audio-pci-intel-lnl 0000:00:1f.3: SoundWire enabled on
CannonLake+ platform, using SOF driver
[ 11.010122] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-p not found, using
dummy regulator
[ 11.010225] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-d not found, using
dummy regulator
[ 11.010250] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-a not found, using
dummy regulator
[ 11.010263] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-io not found, using
dummy regulator
[ 11.010279] cs42l43 sdw:0:0:01fa:4243:01: supply vdd-cp not found, using
dummy regulator
[ 11.015735] cs42l43 sdw:0:0:01fa:4243:01: devid: 0x042a43, rev: 0xa1, otp:
0x03
[ 11.046810] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_P not found, using
dummy regulator
[ 11.046865] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_IO not found, using
dummy regulator
[ 11.046875] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_A not found, using
dummy regulator
[ 11.054838] cs35l56 sdw:0:2:01fa:3556:01:0: Cirrus Logic CS35L56 Rev B0
OTP3 fw:3.4.4 (patched=0)
[ 11.062578] cs35l56 sdw:0:2:01fa:3556:01:0: Slave 2 state check1:
UNATTACHED, status was 1
[ 11.062778] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_P not found, using
dummy regulator
[ 11.062831] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_IO not found, using
dummy regulator
[ 11.062846] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_A not found, using
dummy regulator
[ 11.070812] cs35l56 sdw:0:2:01fa:3556:01:1: Cirrus Logic CS35L56 Rev B0
OTP3 fw:3.4.4 (patched=0)
[ 11.072524] sof-audio-pci-intel-lnl 0000:00:1f.3: Topology file:
intel/sof-ipc4-tplg/sof-lnl-cs42l43-l0-cs35l56-l23-2ch.tplg
[ 11.078035] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_P not found, using
dummy regulator
[ 11.078066] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_IO not found, using
dummy regulator
[ 11.078071] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_A not found, using
dummy regulator
[ 11.085803] cs35l56 sdw:0:3:01fa:3556:01:2: Cirrus Logic CS35L56 Rev B0
OTP3 fw:3.4.4 (patched=0)
[ 11.085911] cs35l56 sdw:0:2:01fa:3556:01:1: Slave 1 state check1:
UNATTACHED, status was 1
[ 11.089553] cs42l43 sdw:0:0:01fa:4243:01: Slave 6 state check1:
UNATTACHED, status was 1
[ 11.092655] cs35l56 sdw:0:3:01fa:3556:01:2: Slave 2 state check1:
UNATTACHED, status was 1
[ 11.092663] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_P not found, using
dummy regulator
[ 11.092683] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_IO not found, using
dummy regulator
[ 11.092688] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_A not found, using
dummy regulator
[ 11.099500] cs35l56 sdw:0:3:01fa:3556:01:3: Cirrus Logic CS35L56 Rev B0
OTP3 fw:3.4.4 (patched=0)
[ 11.110428] cs35l56 sdw:0:3:01fa:3556:01:3: Slave 1 state check1:
UNATTACHED, status was 1
[ 11.706761] cs42l43-codec cs42l43-codec: supply vdd-amp not found, using
dummy regulator
[ 11.735217] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_B not found, using
dummy regulator
[ 11.735235] cs35l56 sdw:0:2:01fa:3556:01:0: supply VDD_AMP not found,
using dummy regulator
[ 11.737319] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_B not found, using
dummy regulator
[ 11.737344] cs35l56 sdw:0:2:01fa:3556:01:1: supply VDD_AMP not found,
using dummy regulator
[ 11.740916] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_B not found, using
dummy regulator
[ 11.740927] cs35l56 sdw:0:3:01fa:3556:01:2: supply VDD_AMP not found,
using dummy regulator
[ 11.743148] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_B not found, using
dummy regulator
[ 11.743179] cs35l56 sdw:0:3:01fa:3556:01:3: supply VDD_AMP not found,
using dummy regulator
[ 11.752570] cs35l56 sdw:0:3:01fa:3556:01:3: DSP1:
cirrus/cs35l56-b0-dsp1-misc-10431e13.wmfw: format 3 timestamp 0x65e6703c
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