Clemens,
Today I got my show-stopper (Griffin FireWave) for OXFW driver and investigate it with easy script (see the end of this message).
Currently firewire-speakers driver handles this device but there're known issues that: 1.the device doesn't generate sounds at some combinations between channels and rates 2.96.0kHz/2ch seems not supported.
As a result of my investigation: The device is known to have two modes: 5.1ch surround mode and Dolby Pro Logic II mode.
At the former mode, stream transfers 6 PCM frames. At the latter mode, stream stransfers 2 PCM frames. The driver can switch these modes to execute AV/C Stream Format Information command with Single subfunction[1]. The purpose of this command is to change internal formation of a packet. Available formations can be retrieved by AV/C Stream Format Information command with Single subfunction[1].
$ ./firewave.sh get Supported stream formats: response: 000: 0c ff bf c1 00 00 00 00 ff 00 00 90 40 04 02 01 ............@... response: 010: 06 06 .. response: 000: 0c ff bf c1 00 00 00 00 ff 00 01 90 40 02 02 01 ............@... response: 010: 06 06 .. response: 000: 0c ff bf c1 00 00 00 00 ff 00 02 90 40 03 02 01 ............@... response: 010: 06 06 .. response: 000: 0c ff bf c1 00 00 00 00 ff 00 03 90 40 05 02 01 ............@... response: 010: 06 06 .. response: 000: 0c ff bf c1 00 00 00 00 ff 00 04 90 40 02 02 01 ............@... response: 010: 02 00 .. response: 000: 0c ff bf c1 00 00 00 00 ff 00 05 90 40 03 02 01 ............@... response: 010: 02 00 .. response: 000: 0c ff bf c1 00 00 00 00 ff 00 06 90 40 04 02 01 ............@... response: 010: 02 00 .. response: 000: 0a ff bf c1 00 00 00 00 ff ff 07 ff ............ Current stream format: response: 000: 0c ff bf c0 00 00 00 00 ff 00 90 40 04 02 01 06 ...........@.... response: 010: 06 . Supported sampling rates in current number of channels: response: 000: 0c ff 19 00 90 00 ff ff ........ response: 000: 0c ff 19 00 90 01 ff ff ........ response: 000: 0c ff 19 00 90 02 ff ff ........ response: 000: 08 ff 19 00 90 03 ff ff ........ response: 000: 0c ff 19 00 90 04 ff ff ........ response: 000: 08 ff 19 00 90 05 ff ff ........ response: 000: 08 ff 19 00 90 06 ff ff ........
According to this output, the available formations of this device are: Mode A. 6ch Multi Bit Linear Audio (MBLA) data at 32.0/44.1/48.0/96.0kHz Mode B. 2ch IEC60958 Compliant data at 32.0/44.1/48.0kHz
For the detail of MBLA and IEC 60958 Compliant data, please refer to [2]. The mode A is equivalent to 5.1ch surround mode, and mode B is equivalent to Dolby Pro Logic II mode. FYI, the last commands are AV/C Plug Signal Format commands[3] and they show the device generally supports 32.0/44.1/48.0/96.0.
As long as I tested, the driver (firewire-speaker) can playback and the device successfully generates sound unless the driver attempts to transfer packets with different number of channels against current setting. For example, when 2ch/48.0kHz is set, then playbacks at 2ch 32.0/44.1/48.0 are successful. Or when 6ch/32.0kHz is set, then playbacks at 6ch 32.0/44.1/48.0/96.0 are successful.
But when the driver attempt to transfer packets with different number of channels, this operation freezes the device. The device desn't react transactions anymore. For example:
$ ./firewave.sh set 44100 6 response: 000: 09 ff bf c0 00 00 00 00 ff 00 90 40 03 02 01 06 ...........@.... response: 010: 06 . $ aplay -D hw:FireWave,0 -f S32_LE -c 2 -r 44100 /dev/urandom (the application and the device freeze)
This causes a bad effect to userspace applications, especially PulseAudio.When connecting sound devices, PulseAudio starts any streams to detect its channel profiles. For FireWave, PulseAudio starts two streams: 2ch and 6ch streams. These operations can freeze the device.
For 96.0kHz/2ch, I tried this: $ ./firewave.sh set 48000 2 response: 000: 09 ff bf c0 00 00 00 00 ff 00 90 40 04 02 01 02 ...........@.... response: 010: 00 . $ aplay -D hw:FireWave -f S32_LE -c 2 -r 96000 /dev/urandom
The device is expected to generate noise but it sounds nothing. Thus I think the device doesn't support this mode.
I have a plan to include improvements for this issue to my patchset for OXFW driver. The patchset will be posted till the beginning of next month, I think.
[1] TA Document 2004008, AV/C Stream Format Information Specification 1.1 (working draft) (April 15, 2005, 1394TA) [2] IEC 61883-6:2005 Consumer audio/video equipment - Digital interface - Part 6: Audio and Music Data Transmission Protocol, Edition 2.0 [2] TA Document 2004006, AV/C Digital Interface Command Set General Specification Version 4.2 (September 1, 2004, 1394TA)
Regards
Takashi Sakamoto o-takashi@sakamocchi.jp
----- 8< ----- $ cat ./firewave.sh
#!/bin/bash
if [ $# -lt 1 ] || [[ $1 != "get" ]] && [[ $1 != "set" ]]; then echo "firewave.sh 'get'" echo "firewave.sh 'set' (32000|44100|48000|96000) (2|6)" exit fi
if [[ $1 == get ]]; then echo "Supported stream formats:"
# AV/C Stream Format Information command with List subfunction for i in $(seq 0 7) ; do ./firewire-request /dev/fw1 fcp $(printf "0x01ffbfc100000000ffff%02xff" $i) done
echo "Current stream format:"
# AV/C Stream Format Information command with Single subfunction ./firewire-request /dev/fw1 fcp 0x01ffbfc000000000ffffffff
echo "Supported sampling rates in current number of channels:"
# AV/C Plug Signal Format command for i in $(seq 0 6); do ./firewire-request /dev/fw1 fcp $(printf "0x02ff190090%02xffff" $i) done
exit fi
if [ ! $# -eq 3 ]; then echo 'Invalid number of arguments.' exit fi
if [ $2 -eq 32000 ] && [ $3 -eq 6 ]; then rate=2 ch=6 format=6 elif [ $2 -eq 44100 ] && [ $3 -eq 6 ]; then rate=3 ch=6 format=6 elif [ $2 -eq 48000 ] && [ $3 -eq 6 ]; then rate=4 ch=6 format=6 elif [ $2 -eq 96000 ] && [ $3 -eq 6 ]; then rate=5 ch=6 format=6 elif [ $2 -eq 32000 ] && [ $3 -eq 2 ]; then rate=2 ch=2 format=0 elif [ $2 -eq 44100 ] && [ $3 -eq 2 ]; then rate=3 ch=2 format=0 elif [ $2 -eq 48000 ] && [ $3 -eq 2 ]; then rate=4 ch=2 format=0 elif [ $2 -eq 96000 ] && [ $3 -eq 2 ]; then rate=5 ch=2 format=0 else echo "Unsupported combination between rate and channel." exit fi
# AV/C Stream Format Information command with Single subfunction ./firewire-request /dev/fw1 fcp $(printf "0x00ffbfc000000000ff009040%02x0201%02x%02x" $rate $ch $format)