[alsa-devel] [PATCH 0/4] ASoC: fix saif record unwork issue

On Wed, Jul 25, 2012 at 01:26:38PM +0800, Lauri Hintsala wrote:

On 07/24/2012 10:21 PM, Mark Brown wrote:

quoted

On Tue, Jul 24, 2012 at 03:46:38PM +0300, Lauri Hintsala wrote:

quoted

1. Recorded audio file is totally silent. Hexdump shows zeros.

This one is commonly due to devices powering up muted by default and
requiring that you set some controls to route the audio through - are
you sure you've not missed anything there?

I tried to set gains and other settings with alsamixer. I didn't see any 
options for muting. Here is the output of amixer.

$ amixer
Simple mixer control 'Headphone',0
   Capabilities: pvolume penum
   Playback channels: Front Left - Front Right
   Limits: Playback 0 - 127
   Mono:
   Front Left: Playback 122 [96%] [9.50dB]
   Front Right: Playback 122 [96%] [9.50dB]
Simple mixer control 'Headphone Mux',0
   Capabilities: enum
   Items: 'DAC' 'LINE_IN'
   Item0: 'LINE_IN'
Simple mixer control 'Headphone Playback ZC',0
   Capabilities: pswitch pswitch-joined penum
   Playback channels: Mono
   Mono: Playback [on]
Simple mixer control 'PCM',0
   Capabilities: pvolume penum
   Playback channels: Front Left - Front Right
   Limits: Playback 0 - 192
   Mono:
   Front Left: Playback 173 [90%]
   Front Right: Playback 173 [90%]
Simple mixer control 'Mic',0
   Capabilities: volume volume-joined penum
   Playback channels: Mono
   Capture channels: Mono
   Limits: 0 - 4
   Mono: 2 [50%] [30.00dB]
Simple mixer control 'Capture',0
   Capabilities: cvolume penum
   Capture channels: Front Left - Front Right
   Limits: Capture 0 - 15
   Front Left: Capture 14 [93%]
   Front Right: Capture 14 [93%]
Simple mixer control 'Capture Attenuate Switch (-6dB)',0
   Capabilities: volume volume-joined penum
   Playback channels: Mono
   Capture channels: Mono
   Limits: 0 - 2
   Mono: 2 [100%]
Simple mixer control 'Capture Mux',0
   Capabilities: enum
   Items: 'MIC_IN' 'LINE_IN'
   Item0: 'LINE_IN'
Simple mixer control 'Capture ZC',0
   Capabilities: pswitch pswitch-joined penum
   Playback channels: Mono
   Mono: Playback [on]

The testing is not currently very reasonable. I have to reboot my 
machine after every single recording because of "busy" bug.

I reproduced your issue.
It seems the root cause is that you used the wrong device to record.
The record device is 1.
root at freescale ~$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: mxssgtl5000 [mxs_sgtl5000], device 0: HiFi Playback sgtl5000-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: mxssgtl5000 [mxs_sgtl5000], device 1: HiFi Capture sgtl5000-1 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Can you try again with below command?
arecord -D hw:0,1 -d 5 -f S16_LE -r 44100 -c 2 1.wav

However, i think it is an issue of the driver that it should report an error
if find user are using a device to do playback or capture without that capability.

I'm wondering soc-core may need provide an interface for user to change the DAI capability
according to the real using, e.g: only playback are used.
I'm not sure if we already have one.
Will do some research on it.

Regards
Dong Aisheng