On Aug 11 2014 00:54, Clemens Ladisch wrote:
Takashi Sakamoto wrote:
I have an issue for Griffin Firewave.
This device can handle AV/C Stream Format Information command and driver can get to know stream formations via the command.
According to these responses, supported formations are: Input Stream to device: Rate PCM MIDI 32000 6 0 44100 6 0 48000 6 0 96000 6 0 32000 2 0 44100 2 0 48000 2 0
But current 'firewire-speakers' has PCM constraints below:
- 6ch at 32/44.1/48/96 kHz
- 2ch at 48/96 kHz
http://mailman.alsa-project.org/pipermail/alsa-devel/2014-February/073562.ht...
So this OXFW driver may lost a support for 2ch/96.0kHz for FireWave and gain 2ch/32.0kHz and 2ch/44.1kHz.
I don't know exactly the reason of these gaps.
The old driver configured nothing but the rate. Is there any mechanism to set the stream format?
Yes. It's AV/C stream format information command.
The old driver uses AV/C plug signal format command. This command basically get/set sampling rate.
But the stream format information command can be available to get/set stream format and some models with OXFW, especially FireWave, uses this command.
But in this series of patches, I don't use this command. I expected the models to change stream format according to parameters in AMDTP packets such like the value of dbs field.
Regards
Takashi Sakamoto (In summer vacation) o-takashi@sakamocchi.jp