On Wed, 26 Feb 2025 14:55:15 +0100, Adrien Vergé wrote:
This fixes a regression introduced a few weeks ago in stable kernels 6.12.14 and 6.13.3. The internal microphone on ASUS Vivobook N705UD / X705UD laptops is broken: the microphone appears in userspace (e.g. Gnome settings) but no sound is detected. I bisected it to commit 3b4309546b48 ("ALSA: hda: Fix headset detection failure due to unstable sort").
I figured out the cause:
- The initial pins enabled for the ALC256 driver are: cfg->inputs == { { pin=0x19, type=AUTO_PIN_MIC, is_headset_mic=1, is_headphone_mic=0, has_boost_on_pin=1 }, { pin=0x1a, type=AUTO_PIN_MIC, is_headset_mic=0, is_headphone_mic=0, has_boost_on_pin=1 } }
- Since 2017 and commits c1732ede5e8 ("ALSA: hda/realtek - Fix headset and mic on several ASUS laptops with ALC256") and 28e8af8a163 ("ALSA: hda/realtek: Fix mic and headset jack sense on ASUS X705UD"), the quirk ALC256_FIXUP_ASUS_MIC is also applied to ASUS X705UD / N705UD laptops. This added another internal microphone on pin 0x13: cfg->inputs == { { pin=0x13, type=AUTO_PIN_MIC, is_headset_mic=0, is_headphone_mic=0, has_boost_on_pin=1 }, { pin=0x19, type=AUTO_PIN_MIC, is_headset_mic=1, is_headphone_mic=0, has_boost_on_pin=1 }, { pin=0x1a, type=AUTO_PIN_MIC, is_headset_mic=0, is_headphone_mic=0, has_boost_on_pin=1 } } I don't know what this pin 0x13 corresponds to. To the best of my knowledge, these laptops have only one internal microphone.
- Before 2025 and commit 3b4309546b48 ("ALSA: hda: Fix headset detection failure due to unstable sort"), the sort function would let the microphone of pin 0x1a (the working one) *before* the microphone of pin 0x13 (the phantom one).
- After this commit 3b4309546b48, the fixed sort function puts the working microphone (pin 0x1a) *after* the phantom one (pin 0x13). As a result, no sound is detected anymore.
It looks like the quirk ALC256_FIXUP_ASUS_MIC is not needed anymore for ASUS Vivobook X705UD / N705UD laptops. Without it, everything works fine:
- the internal microphone is detected and records actual sound,
- plugging in a jack headset is detected and can record actual sound with it,
- unplugging the jack headset makes the system go back to internal microphone and can record actual sound.
Cc: stable@vger.kernel.org Cc: Kuan-Wei Chiu visitorckw@gmail.com Cc: Chris Chiu chris.chiu@canonical.com Fixes: 3b4309546b48 ("ALSA: hda: Fix headset detection failure due to unstable sort") Tested-by: Adrien Vergé adrienverge@gmail.com Signed-off-by: Adrien Vergé adrienverge@gmail.com
Thanks, applied now.
Takashi