[alsa-devel] IEC61937 passthrough with BYT/CHT HdmiLpeAudio
Hi Takashi,
While I was looking at IEC61937, I ran a quick test on my BYT and CHT boxes, and as I suspected IEC61937 works fine since your modifications to add s16_le support. I can get AC3 to my HDMI receiver without problems just by using the hw:0,<1,2,3> device, depending on which port is used.
e.g. aplay -Dhw:0,2 -c2 -r48000 -fs16le ac3_surround_test.spdif
To make things more usable for applications, and maybe support receivers who actually care about the AES0 non-audio bit or reduce the initial lock time, it'd be nice to support the traditional command line, e.g.
aplay -D'hdmi:CARD=0,DEV=<0,1,2>,AES0=0x6' -c2 -r48000 -fs16_le ac3_surround_test.spdif
However we seem to have a mix of alsa-lib configuration issues and maybe a miss at the driver level
I added the missing devices in HdmiLpeAudio.conf with the patch below, which helps select the right output, but somehow the AES0 non-audio bit doesn't seem to be set.
[plb@ZOTAC PASSTHROUGH]$ amixer -Dhw:0 cget numid=12 numid=12,iface=PCM,name='IEC958 Playback Default',device=2 ; type=IEC958,access=rw------,values=1 : values=[AES0=0x00 AES1=0x00 AES2=0x00 AES3=0x00] [plb@ZOTAC PASSTHROUGH]$ aplay -D'hdmi:CARD=0,DEV=2,AES0=0x6' -c2 -r48000 -fs16_le ac3_surround_test.spdif Playing raw data 'ac3_surround_test.spdif' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo ^CAborted by signal Interrupt... [plb@ZOTAC PASSTHROUGH]$ amixer -Dhw:0 cget numid=12numid=12,iface=PCM,name='IEC958 Playback Default',device=2 ; type=IEC958,access=rw------,values=1 : values=[AES0=0x00 AES1=0x00 AES2=0x00 AES3=0x00]
Could it be that we are missing the 'index' which is used in the HDaudio case to access the 'IEC958 Playback Default' controls?
Thanks
-Pierre
diff HdmiLpeAudio.conf /usr/share/alsa/cards/HdmiLpeAudio.conf 59,135d58 < device 0 < lock true < preserve true < value [ $AES0 $AES1 $AES2 $AES3 ] < } < ] < } < } < < HdmiLpeAudio.pcm.hdmi.1 { < @args [ CARD AES0 AES1 AES2 AES3 ] < @args.CARD { < type string < } < @args.AES0 { < type integer < } < @args.AES1 { < type integer < } < @args.AES2 { < type integer < } < @args.AES3 { < type integer < } < type hooks < slave.pcm { < type hw < card $CARD < device 1 < } < hooks.0 { < type ctl_elems < hook_args [ < { < interface PCM < name "IEC958 Playback Default" < device 1 < lock true < preserve true < value [ $AES0 $AES1 $AES2 $AES3 ] < } < ] < } < } < < HdmiLpeAudio.pcm.hdmi.2 { < @args [ CARD AES0 AES1 AES2 AES3 ] < @args.CARD { < type string < } < @args.AES0 { < type integer < } < @args.AES1 { < type integer < } < @args.AES2 { < type integer < } < @args.AES3 { < type integer < } < type hooks < slave.pcm { < type hw < card $CARD < device 2 < } < hooks.0 { < type ctl_elems < hook_args [ < { < interface PCM < name "IEC958 Playback Default" < device 2
On Wed, 16 Aug 2017 17:15:09 +0200, Pierre-Louis Bossart wrote:
Hi Takashi,
While I was looking at IEC61937, I ran a quick test on my BYT and CHT boxes, and as I suspected IEC61937 works fine since your modifications to add s16_le support. I can get AC3 to my HDMI receiver without problems just by using the hw:0,<1,2,3> device, depending on which port is used.
e.g. aplay -Dhw:0,2 -c2 -r48000 -fs16le ac3_surround_test.spdif
To make things more usable for applications, and maybe support receivers who actually care about the AES0 non-audio bit or reduce the initial lock time, it'd be nice to support the traditional command line, e.g.
aplay -D'hdmi:CARD=0,DEV=<0,1,2>,AES0=0x6' -c2 -r48000 -fs16_le ac3_surround_test.spdif
However we seem to have a mix of alsa-lib configuration issues and maybe a miss at the driver level
Yeah, alsa-lib config is still not updated to follow the recent changes in kernel side. It needs multiple HDMI entries.
I added the missing devices in HdmiLpeAudio.conf with the patch below, which helps select the right output, but somehow the AES0 non-audio bit doesn't seem to be set.
[plb@ZOTAC PASSTHROUGH]$ amixer -Dhw:0 cget numid=12 numid=12,iface=PCM,name='IEC958 Playback Default',device=2 ; type=IEC958,access=rw------,values=1 : values=[AES0=0x00 AES1=0x00 AES2=0x00 AES3=0x00] [plb@ZOTAC PASSTHROUGH]$ aplay -D'hdmi:CARD=0,DEV=2,AES0=0x6' -c2 -r48000 -fs16_le ac3_surround_test.spdif Playing raw data 'ac3_surround_test.spdif' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo ^CAborted by signal Interrupt... [plb@ZOTAC PASSTHROUGH]$ amixer -Dhw:0 cget numid=12numid=12,iface=PCM,name='IEC958 Playback Default',device=2 ; type=IEC958,access=rw------,values=1 : values=[AES0=0x00 AES1=0x00 AES2=0x00 AES3=0x00]
Did you check the value during the playback? Since you set "preserve" in HDMI config, the old value gets restored at closing the PCM.
thanks,
Takashi
Could it be that we are missing the 'index' which is used in the HDaudio case to access the 'IEC958 Playback Default' controls?
Thanks
-Pierre
diff HdmiLpeAudio.conf /usr/share/alsa/cards/HdmiLpeAudio.conf 59,135d58 < device 0 < lock true < preserve true < value [ $AES0 $AES1 $AES2 $AES3 ] < } < ] < } < } < < HdmiLpeAudio.pcm.hdmi.1 { < @args [ CARD AES0 AES1 AES2 AES3 ] < @args.CARD { < type string < } < @args.AES0 { < type integer < } < @args.AES1 { < type integer < } < @args.AES2 { < type integer < } < @args.AES3 { < type integer < } < type hooks < slave.pcm { < type hw < card $CARD < device 1 < } < hooks.0 { < type ctl_elems < hook_args [ < { < interface PCM < name "IEC958 Playback Default" < device 1 < lock true < preserve true < value [ $AES0 $AES1 $AES2 $AES3 ] < } < ] < } < } < < HdmiLpeAudio.pcm.hdmi.2 { < @args [ CARD AES0 AES1 AES2 AES3 ] < @args.CARD { < type string < } < @args.AES0 { < type integer < } < @args.AES1 { < type integer < } < @args.AES2 { < type integer < } < @args.AES3 { < type integer < } < type hooks < slave.pcm { < type hw < card $CARD < device 2 < } < hooks.0 { < type ctl_elems < hook_args [ < { < interface PCM < name "IEC958 Playback Default" < device 2
On 08/16/2017 10:52 AM, Takashi Iwai wrote:
On Wed, 16 Aug 2017 17:15:09 +0200, Pierre-Louis Bossart wrote:
Hi Takashi,
While I was looking at IEC61937, I ran a quick test on my BYT and CHT boxes, and as I suspected IEC61937 works fine since your modifications to add s16_le support. I can get AC3 to my HDMI receiver without problems just by using the hw:0,<1,2,3> device, depending on which port is used.
e.g. aplay -Dhw:0,2 -c2 -r48000 -fs16le ac3_surround_test.spdif
To make things more usable for applications, and maybe support receivers who actually care about the AES0 non-audio bit or reduce the initial lock time, it'd be nice to support the traditional command line, e.g.
aplay -D'hdmi:CARD=0,DEV=<0,1,2>,AES0=0x6' -c2 -r48000 -fs16_le ac3_surround_test.spdif
However we seem to have a mix of alsa-lib configuration issues and maybe a miss at the driver level
Yeah, alsa-lib config is still not updated to follow the recent changes in kernel side. It needs multiple HDMI entries.
I added the missing devices in HdmiLpeAudio.conf with the patch below, which helps select the right output, but somehow the AES0 non-audio bit doesn't seem to be set.
[plb@ZOTAC PASSTHROUGH]$ amixer -Dhw:0 cget numid=12 numid=12,iface=PCM,name='IEC958 Playback Default',device=2 ; type=IEC958,access=rw------,values=1 : values=[AES0=0x00 AES1=0x00 AES2=0x00 AES3=0x00] [plb@ZOTAC PASSTHROUGH]$ aplay -D'hdmi:CARD=0,DEV=2,AES0=0x6' -c2 -r48000 -fs16_le ac3_surround_test.spdif Playing raw data 'ac3_surround_test.spdif' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo ^CAborted by signal Interrupt... [plb@ZOTAC PASSTHROUGH]$ amixer -Dhw:0 cget numid=12numid=12,iface=PCM,name='IEC958 Playback Default',device=2 ; type=IEC958,access=rw------,values=1 : values=[AES0=0x00 AES1=0x00 AES2=0x00 AES3=0x00]
Did you check the value during the playback? Since you set "preserve" in HDMI config, the old value gets restored at closing the PCM.
yes, that was the issue, thanks. I'll send a patch just now, it works fine
thanks,
Takashi
Could it be that we are missing the 'index' which is used in the HDaudio case to access the 'IEC958 Playback Default' controls?
Thanks
-Pierre
diff HdmiLpeAudio.conf /usr/share/alsa/cards/HdmiLpeAudio.conf 59,135d58 < device 0 < lock true < preserve true < value [ $AES0 $AES1 $AES2 $AES3 ] < } < ] < } < } < < HdmiLpeAudio.pcm.hdmi.1 { < @args [ CARD AES0 AES1 AES2 AES3 ] < @args.CARD { < type string < } < @args.AES0 { < type integer < } < @args.AES1 { < type integer < } < @args.AES2 { < type integer < } < @args.AES3 { < type integer < } < type hooks < slave.pcm { < type hw < card $CARD < device 1 < } < hooks.0 { < type ctl_elems < hook_args [ < { < interface PCM < name "IEC958 Playback Default" < device 1 < lock true < preserve true < value [ $AES0 $AES1 $AES2 $AES3 ] < } < ] < } < } < < HdmiLpeAudio.pcm.hdmi.2 { < @args [ CARD AES0 AES1 AES2 AES3 ] < @args.CARD { < type string < } < @args.AES0 { < type integer < } < @args.AES1 { < type integer < } < @args.AES2 { < type integer < } < @args.AES3 { < type integer < } < type hooks < slave.pcm { < type hw < card $CARD < device 2 < } < hooks.0 { < type ctl_elems < hook_args [ < { < interface PCM < name "IEC958 Playback Default" < device 2
participants (2)
-
Pierre-Louis Bossart -
Takashi Iwai