No speaker audio on Samsung Galaxy Book 940XGK (Meteor Lake + MAX98390 I2C amplifiers)

[Rafasamarall]

Hardware
Laptop: Samsung 940XGK (Galaxy Book, NP940XGK-KG1BR)
BIOS: P13VAG.810.251121.04
CPU/Audio: Intel Meteor Lake-P (sof-audio-pci-intel-mtl 0000:00:1f.3)
HDA Codec: Realtek ALC298 (subsystem ID 0x144dca07)
Speaker Amplifiers: 3x Maxim MAX98390 on I2C bus 3 (addresses 0x39, 0x3c, 0x3d)
ACPI HID: MAX98390
DMICs: 2

System
Distro: Debian 13 (trixie)
Kernel: 6.19.6+deb13-amd64
SOF firmware: firmware-sof-signed 2025.01-1 (also tested with upstream sof-bin v2025.12.2)
PipeWire: 1.4.2

Problem
Internal speakers produce no sound. The HDA headphone output through ALC298 works fine, but the MAX98390 I2C speaker amplifiers have no kernel support for this Meteor Lake configuration.

Details from dmesg
sof-audio-pci-intel-mtl 0000:00:1f.3: using HDA machine driver skl_hda_dsp_generic now
sof-audio-pci-intel-mtl 0000:00:1f.3: loading topology: intel/sof-ipc4-tplg/sof-hda-generic-2ch.tplg
snd_hda_codec_alc269 ehdaudio0D0: autoconfig for ALC298: line_outs=1 (0x17/0x0/0x0/0x0/0x0) type:speaker
i2c i2c-3: new_device: Instantiated device max98390-hda at 0x39
i2c i2c-3: new_device: Instantiated device max98390-hda at 0x3c
i2c i2c-3: new_device: Instantiated device max98390-hda at 0x3d

I2C scan confirms devices present
$ sudo i2cdetect -r -y 3
0 1 2 3 4 5 6 7 8 9 a b c d e f
30: -- -- -- -- -- -- -- -- 38 39 -- -- 3c 3d -- --

What's missing
No entry in soc-acpi-intel-mtl-match.c for MAX98390 on MTL SSP
No sof-mtl-max98390*.tplg IPC4 topology file exists
The snd_soc_max98390 I2C driver doesn't match the i2c:max98390-hda modalias (only matches i2c:max98390)
The ACPI device MAX98390:00 is detected but the three I2C codec instances at 0x39/0x3c/0x3d remain unbound

ACPI info
ACPI path: _SB_.PC00.I2C2.MX98
ACPI status: 15 (present + enabled)
Device modalias: i2c:max98390-hda
NHLT: BT ssp_mask 0x4, DMICs: 2

[Rafasamarall]

I found the root cause of my immediate issue. I had a DKMS out-of-tree module (snd_hda_scodec_max98390) that was working on kernel 6.12.73. When I upgraded to kernel 6.19.6 (Debian backports), the DKMS module failed to build due to the MODULE_IMPORT_NS / EXPORT_SYMBOL_NS_GPL API change (now requires string arguments instead of bare identifiers).

After fixing the source and rebuilding the DKMS module, my speakers work again on 6.19.6.

However, the core issue remains: there is no native in-tree support for MAX98390 HDA amplifiers on Intel Meteor Lake (Samsung Galaxy Book). The hardware requires:

1. A snd-hda-scodec-max98390 driver (HDA component codec for MAX98390)
2. A systemd service or serial-multi-instantiate support to bind the I2C devices (0x39, 0x3c, 0x3d on bus 3)
3. Proper quirk entries in snd_hda_codec_realtek for ALC298 + MAX98390 (subsystem ID 0x144dca07)

I'm currently relying on a DKMS workaround. Would appreciate native kernel support for this hardware.