[alsa-devel] Intel Cherry Trail and NAU8824 codec

[TheKit]

Hello,

I'm trying to get sound working in Linux on Cube iWork8 Ultimate
tablet. It has Windows/Android dualboot, but no kernel sources for
Android, unfortunately. From dmesg I see that NAU8824 codec is used,
which I can't find any drivers for, except proposed patch that wasn't
merged: https://lkml.org/lkml/2015/3/4/765

But, as I understand, additional code (like
https://github.com/kirananto/ZENFONE2/blob/master/sound/soc/intel/board/cht_bl_dpcm_rt5672.c)
is needed to bridge it with Cherry Trail SoC. Any suggestions how to
go about this?

Relevant lines of dmesg from stock Android kernel (where sound works):
<6>[    8.665477] nau8824_i2c_probe enter
<3>[    8.666609] snd_intel_sst: sst_platform_get_resources_edk
<3>[    8.672489] snd_intel_sst: LPE base: 0x91600000
size:0x200000snd_intel_sst: IRAM base: 0x916c0000
<3>[    8.682557] snd_intel_sst: DRAM base: 0x91700000snd_intel_sst:
SHIM base: 0x91740000
<3>[    8.691298] snd_intel_sst: Mailbox base:
0x91744000snd_intel_sst: DDR base: 0x20000000
<6>[    8.700428] snd_intel_sst: Enter: sst_audio_platform_init
<6>[    8.700646] snd_intel_sst: audio:set_cht_platform_config
<6>[    8.700900] snd_soc_sst_platform: sst_platform_probe is deferred
<6>[    8.700918] platform sst-platform: Driver sst-platform requests
probe deferral
<3>[    8.700927] snd_intel_sst: board_name:Cherry Trail CR
<6>[    8.706611] snd_intel_sst: Registering machine device cht_nau88l24
<3>[    8.707127] snd_intel_sst: Requesting FW fw_sst_22a8.bin now...
<4>[    8.713815] intel_sst_acpi 808622A8:00: Direct firmware load
failed with error -2
<4>[    8.724734] intel_sst_acpi 808622A8:00: Falling back to user helper
<6>[    8.789741] platform cht_nau88l24: Driver cht_nau88l24 requests
probe deferral
<6>[    8.789967] cht_cr_nau88l24: Cherrytrail Machine Driver
cht_nau8824 registerd
<6>[    9.077571] snd_soc_sst_platform: sst_platform_probe is deferred
<3>[   10.856689] sst-platform sst-platform: ASoC: no sink widget
found for Audio Capture
<3>[   10.856693] sst-platform sst-platform: ASoC: Failed to add route
media3_out -> direct -> Audio Capture
<6>[   10.873799] nau8824_codec_probe enter
<6>[   11.062658] cht_nau88l24 cht_nau88l24: snd-soc-dummy-dai <->
Headset-cpu-dai mapping ok
<6>[   11.062754] cht_nau88l24 cht_nau88l24: snd-soc-dummy-dai <->
Deepbuffer-cpu-dai mapping ok
<6>[   11.062902] cht_nau88l24 cht_nau88l24: snd-soc-dummy-dai <->
Voip-cpu-dai mapping ok
<6>[   11.063035] cht_cr_nau88l24: cht_hs_detection:Check hs insertion
 after 500 msec
<6>[   11.063035] cht_nau88l24 cht_nau88l24: snd-soc-dummy-dai <->
Lowlatency-cpu-dai mapping ok
<6>[   11.063383] cht_nau88l24 cht_nau88l24: snd-soc-dummy-dai <->
Probe-cpu-dai mapping ok
<6>[   11.063596] cht_nau88l24 cht_nau88l24: nau8824-aif1 <->
ssp2-port mapping ok
<6>[   11.063638] cht_nau88l24 cht_nau88l24: snd-soc-dummy-dai <->
snd-soc-dummy-dai mapping ok
<6>[   11.063674] cht_nau88l24 cht_nau88l24: snd-soc-dummy-dai <->
snd-soc-dummy-dai mapping ok
<3>[   11.063742] cht_nau88l24 cht_nau88l24: ASoC: Failed to add
Headset Mic Switch: -16
<6>[   11.095628] input: cherrytrailaud Headset Jack as
/devices/platform/cht_nau88l24/sound/card1/input9
<6>[   11.096265] cht_cr_nau88l24: snd_cht_mc_probe successful