On Wed, 2016-11-23 at 13:22 +0800, Shrirang Bagul wrote:

Hi,

I'm attempting to enable audio on Intel Atom E3815. I have a board with RT5660 codec from Realtek connected to the SoC over I2S2. The codec can be configured over I2C bus. The board supports External Mic In and Line Out connections for audio.

I am running Ubuntu 16.04 LTS with kernel v4.4.

To support RT5660 codec, I have backported patches - d01580c ASoC: rt5660: enable MCLK detection 2b26dd4 ASoC: rt5660: add rt5660 codec driver from https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git topic/rt5660 branch

To support I2S_CLK using MCLK I've also backported the patch to support PMC platform clocks - [13/17] clk: x86: Add Atom PMC platform clocks (https://patchwork.kernel.org/pat ch/9277989/)

To understand the I2S over LPE architecture for audio I'm referring to the Intel Atom Processor E3800: Datasheet (http://www.intel.com/content/dam/www/public/us/ en/documents/datasheets/atom-e3800-family-datasheet.pdf) and discussions on alsa-devel mailing list thread: http://mailman.alsa-project.org/pipermail/alsa-d evel/2015-November/100303.html

After implementing the machine driver byt-rt5660.c (by referring to byt- rt5640.c), the CPU DAI baytrail-pcm-audio is registered successfully and the fw_sst_0f28.bin-48kHz_i2s_master firmware also is loaded without any errors. It is possible to configure the codec controls using alsamixer.

However, an attempt to record results in an empty PCM file and no audio is heard if I try to playback using aplay.

I'm assuming the pointer is being incremented on playback ? It's sometimes helpful to disable pulseaudio and try directly with aplay.

You can also try aplay -Dhw0,0 --test-position

If the position is moving then it's likely the codec mixer configuration is missing something or your MCLK is missing ?

The record result seems like the DSP is not capturing data. Can you try again without pulseaudio and use arecord -Dhw:0,0 --test-position. Is there anything in dmesg after plyback/capture ?

I'm clueless on how to proceed from this point onward in getting the audio to work on this board. The ouput of alsa-info.sh, clk_summary & gpio config from debugfs and dmesg log is attached with this message. I have published the source code here: http://kernel.ubuntu.com/git/snb/ubuntu-xenial.git/log/?h=x-master-au dio-test

I would highly appreciate your help!

Liam