How to get AC3 passthrough on Freescale IMX6 Yocto image ?

[subodh]

Hi,

I am using a SABRE-SD IMX6 Quad board.

I have built the image using instructions from freescale git for

3.10.31+. (Not using X11, instead trying with directfb ).

I have working gstreamer 0.10 and 1.0 on board and can decode audio and

playback on HDMI

using the following settings for ALSA.

https://community.freescale.com/docs/DOC-93745

But I need to pass the audio directly to HDMI for decoding.

Is pulseaudio a must for getting passthrough to work ?

Please let me know in case more information from my setup is needed.

Thanks.

Following is my board setup

root@imx6qsabresd:~# aplay -l

**** List of PLAYBACK Hardware Devices ****

card 0: imxhdmisoc [imx-hdmi-soc], device 0: i.MX HDMI Audio Tx

hdmi-hifi-0 []

   Subdevices: 1/1

   Subdevice #0: subdevice #0

root@imx6qsabresd:~# uname -a

Linux imx6qsabresd 3.10.31-1.1.0_beta+g94a7e47 #1 SMP PREEMPT Sun Oct 12

02:14:32 IST 2014 armv7l GNU/Linux

root@imx6qsabresd:~# gst-inspect-1.0 | grep pulse

pulseaudio:  pulsesink: PulseAudio Audio Sink

pulseaudio:  pulsesrc: PulseAudio Audio Source

root@imx6qsabresd:~# ls /usr/lib/pulseaudio/libpulsecommon-5.0.so

/usr/lib/pulseaudio/libpulsecommon-5.0.so

Regards,

Subodh

[weidong_sun]

Hello Subodh,

    I think your request should be no problem, please refer to document named i.MX_6_linux_Reference_Manual.pdf !  you can get more information.

Regards,

Weidong

[subodh]

Hi weidong.sun

Thanks for the reference.

Following is the output I get for iecset. But I fail to play any ac3 content using gstreamer-1.0.

I only have 5.1 audio content and the audioconvert element in gstreamer converts it to stereo for playback.

Could this behavior be triggered by the HDMI monitor device being a 2 channel sink ?

Could you suggest some other tests to confirm if my board is getting configured correctly?     

root@imx6qsabresd:/unit_tests# iecset -c1

Mode: consumer

Data: audio

Rate: 48000 Hz

Copyright: permitted

Emphasis: none

Category: general

Original: 1st generation

Clock: 1000 ppm

Test case results ( Looks like some configuration issue as both are failing) :

=======================================================

root@imx6qsabresd:/unit_tests# ./mxc_cec_test.out

Start CEC testing!

Unable to Open HDMI CEC device

Don't initialize hdmi cec!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

sleep for ready!

^C

root@imx6qsabresd:/unit_tests# ./autorun-sound.sh

Checking for devnode: /dev/dsp

autorun-sound.sh: FAIL devnode not found: /dev/dsp

Checking for devnode: /dev/adsp

autorun-sound.sh: FAIL devnode not found: /dev/adsp

Checking for devnode: /dev/audio

autorun-sound.sh: FAIL devnode not found: /dev/audio

Checking for devnode: /dev/mixer

autorun-sound.sh: FAIL devnode not found: /dev/mixer

autorun-sound.sh: Exiting FAIL

Thanks and Regards,

Subodh