Bug 83851

Summary:	snd_soc_sst_acpi / rt5640: Microphone not working
Product:	Drivers	Reporter:	Jan-Michael Brummer (jan.brummer)
Component:	Sound(ALSA)	Assignee:	Jaroslav Kysela (perex)
Status:	NEW ---
Severity:	normal	CC:	giacomo.handjaras, jarkko.nikula, pierre-louis.bossart, softwarefreedomsolutions
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	3.16	Subsystem:
Regression:	No	Bisected commit-id:

Description Jan-Michael Brummer 2014-09-03 20:31:05 UTC

Using snd_soc_sst_acpi the audio device within the Dell Venue 8 Pro tablet is working fine for audio output as long a alsa state file is loaded. Audio input on the other hand is not working at all, there is only a constant noise level on the volume bar. What kind of debug logs are necessary in order to analyse this issue in case this is not already known?

Comment 1 Jarkko Nikula 2014-10-03 13:56:56 UTC

We have been debugging this off-list with Jan. There are couple patches queued for byt-rt5640 based machines along the patch that adds microphone support for the Dell Venue 8 Pro tablet:

https://git.kernel.org/cgit/linux/kernel/git/broonie/sound.git/commit/?h=for-next&id=24221dcc8be736a2b0b83ecaeb60b99bd7e9334c

These patches most probably will be queued for Linux 3.18.

Comment 2 Bobby Budnick 2015-02-19 22:29:41 UTC

I am trying to capture sound from the internal microphone of the Dell Venue 8 Pro 5830 and I am only getting static.  I am running a compiled 3.18 kernel with the referenced patch already added.  I am also using an alsa state file that allows for sound playback.  Are there certain alsamixer options that should be enabled?  I have played with the alsamixer settings with no luck.

Comment 3 Giacomo H 2015-02-22 10:38:46 UTC

I have the same issue with an ASUS T100: no sound from the internal microphone! I have tried kernel 3.18 and 3.19, Fedlet and Ubuntu, without any luck. The patches of Jarkko Nikula enabled recording from an EXTERNAL microphone (connected to the mini-jack port of the tablet), at least for my device.

Comment 4 Pierre Bossart 2016-11-29 18:47:08 UTC

please try with a more recent kernel, this should be fixed.