alsa-project/alsa-ucm-conf issue #687 was opened from akincano:

### Hardware Information - Laptop: ASUS ZenBook UX425EA_UX425EA - Audio Controller: Intel Tiger Lake-LP Smart Sound Technology - Audio Controller (PCI ID: 0x8086:0xa0c8) - Codec: Realtek ALC294 (Vendor ID: 0x10ec0294, Subsystem ID: 0x10431cee) - Kernel: 6.18.5.arch1-1 - Distribution: Arch Linux

### Software Versions ```bash alsa-ucm-conf 1.2.15.2-1 sof-firmware 2025.12-1 linux 6.18.5.arch1-1 ```

### Problem Description The SOF HiFi profile fails to create speaker/headphone audio devices on this hardware. WirePlumber reports: ```bash spa.alsa: No sink and source at HiFi: Headphones ``` The HiFi profile shows as available: no and only HDMI outputs are exposed, with no analog audio devices.

### Root Cause **This is a UCM configuration issue**, not a kernel driver issue. The problem is that /usr/share/alsa/ucm2/HDA/HiFi-analog.conf checks for ALSA controls that don't exist on this hardware.

**ALSA controls exposed by this hardware (identical for both SOF and HDA):** ```bash numid=3,iface=CARD,name='Speaker Phantom Jack' numid=2,iface=MIXER,name='Master Playback Switch' numid=1,iface=MIXER,name='Master Playback Volume' [HDMI/IEC958 controls omitted for brevity] ```

**Controls the UCM config expects but don't exist:** - Headphone Playback Volume ❌ (only Master Playback Volume exists) - Headphone Playback Switch ❌ (only Master Playback Switch exists) - Headphone Jack ❌ (only Speaker Phantom Jack exists)

**UCM config logic that fails:** In /usr/share/alsa/ucm2/HDA/HiFi-analog.conf: ```bash If.hpvol { Condition { Type ControlExists Control "name='Headphone Playback Volume'" } False.Define.hpvol "" }

If.hp { Condition { Type String Empty "${var:hpvol}" } False.SectionDevice."Headphones" { # ... creates headphone device } } ``` Because Headphone Playback Volume doesn't exist, hpvol is set to empty string, and the If.hp condition prevents the headphone device from being created.

Similarly, the jack detection logic checks for: ```bash Define.hpjack "Headphone Jack" If.hpjack { Condition { Type ControlExists Control "iface=CARD,name='Headphone Mic Jack'" } # ... falls back to checking 'Front Headphone Jack' } ``` But never checks for Speaker Phantom Jack, which is what this hardware exposes.

### Working Configuration (Legacy HDA Driver) With the legacy snd_hda_intel driver (forced via blacklisting SOF), PulseAudio's built-in profile logic correctly handles this hardware:

**Working profile:** output:analog-stereo+input:analog-stereo

**Exposed ports:** - analog-output-speaker: Speakers (uses Master Playback Volume/Switch) - analog-output-headphones: Headphones (uses Master Playback Volume/Switch) - Automatic jack detection via Speaker Phantom Jack

The legacy HDA driver works because PulseAudio has fallback logic that handles hardware with only Master volume controls, but SOF's UCM-based configuration doesn't have this fallback.

### Proposed Solution The UCM configuration needs to be updated to handle hardware that only exposes Master Playback Volume/Switch instead of dedicated Headphone controls.

**Option 1: Add fallback logic to HiFi-analog.conf**

Check for Master Playback Volume when Headphone Playback Volume doesn't exist: ```bash If.hpvol { Condition { Type ControlExists Control "name='Headphone Playback Volume'" } False.If.master { Condition { Type ControlExists Control "name='Master Playback Volume'" } True.Define.hpvol "Master" } } ```

Similarly for jack detection, check Speaker Phantom Jack: ```bash If.hpjack { Condition { Type ControlExists Control "iface=CARD,name='Headphone Mic Jack'" } True.Define.hpjack "Headphone Mic Jack" False.If.front { Condition { Type ControlExists Control "iface=CARD,name='Front Headphone Jack'" } True.Define.hpjack "Front Headphone Jack" False.If.speaker { Condition { Type ControlExists Control "iface=CARD,name='Speaker Phantom Jack'" } True.Define.hpjack "Speaker Phantom Jack" } } } ```

**Option 2: Create a specific profile for this hardware**

Create a UCM profile specifically for Tiger Lake systems with Realtek ALC294 that only expose Master controls.

**Option 3: Update SOF topology** If this is a SOF topology issue, update the topology to expose proper Headphone controls instead of just Master.

### Additional Debug Information **Pin 0x21 configuration (headphone jack):** ```bash Node 0x21 [Pin Complex] wcaps 0x40058d: Stereo Amp-Out Pincap 0x0001001c: OUT HP EAPD Detect Pin Default 0x411111f0: [N/A] Speaker at Ext Rear Misc = NO_PRESENCE Pin-ctls: 0x00: Unsolicited: tag=00, enabled=0 ``` The pin is capable of jack detection (EAPD Detect in capabilities) but is misconfigured as "N/A" with "NO_PRESENCE". However, the jack detection still works via the Speaker Phantom Jack ALSA control.

**Full codec information:** Available upon request

**Full WirePlumber logs:** Available upon request

### Impact This affects all ASUS ZenBook UX425EA users (and potentially other laptops with similar hardware configurations) running SOF. Users must either:

1. Use pro-audio profile (no automatic headphone/speaker switching) 2. Blacklist SOF and force legacy HDA driver (not a long-term solution)

### Related Issues This was initially reported in #686 which was closed as a kernel issue, but further investigation revealed it's actually a UCM configuration problem. The kernel driver is exposing the ALSA controls correctly; the UCM config just doesn't know how to handle this hardware configuration.

Issue URL : https://github.com/alsa-project/alsa-ucm-conf/issues/687 Repository URL: https://github.com/alsa-project/alsa-ucm-conf