Here are the results of a few quick smoke tests.
First I attached FireWave and Speakers to my Mac mini and booted into OS X to make sure that this hardware still works. Both do. I don't have Griffin's driver installed. The FireWave puts out proper stereo sound on the L/R port, some muffled sound and pops on the C/S port, and nothing on the LS/RS port. The Speakers put out a loud tinny sound as expected from them.
Rebooted into Linux (2.6.38-rc3). snd_firewire_speakers gets loaded right after I modprobed firewire-ohci, yet somehow no devices are bound to it. (I guess I will add some printks here to look closer onto the device probe under various circumstances.) Removed the speakers, and perhaps replugged the FireWave. They get bound, programs show them as sound card. Unloaded the snd_hda_intel driver to make testing easier.
Xine, although configured to the alsa backend, somehow refuses to use the alsa backend and falls through to jack which doesn't have any devices present at the moment. Kaffeine which uses xine as backend pops up a window that it can't open the sound device. Audacious complains about missing mixer and can't use this sound card.
KDE4's hardware control, sound pane, shows the card and lets me play the test sound on it. First few seconds are choppy. Shortly after the test sound faded I press teh test button again and get a kernel panic:
BUG: unable to handle kernel paging request at [...] IP: [...] iso_packets_buffer_destroy+0x8/0x1d [snd_firewire_lib] [...] Call Trace: [...] amdtp_out_stream_stop+0x3b/0x46 [snd_firewire_lib] [...]
I will send you a screenshot off list.
Next test: Plugged the Speakers in, unloaded snd_hda_intel, loaded firewire-ohci, snd_firewire_speakers now gets bound to devie right away. Started xine and played a file. No complaint. (Hmm, I wonder whether I had an operator error in my earlier session with FireWave.) There is the same problem as in the first KDE4 control panel test: Playback starts with an Autechre remix during the first few seconds. ;-)
Subsequent pause/resume or program exit/ program restart of xine do not feature the choppy lead in anymore.
Audacious again pops up a window titled "ALSA error", saying "No suitable mixer element found." But it actually plays back now.
Alas the missing mixer makes the whole affair not quite usable yet: The LaCie FireWire Speakers are very loud; too loud for the desk or living room. On OS X, I had their volume pulled down to the lowest mark.
No kernel panic yet.
Plugged Speakers out and FireWave in. Gets bound. Xine plays back, as does Audacious (which again first the missing mixer nag window). Alas there is choppy noise during the whole playback, with different audio sources.
Reboot with FireWave plugged in. Same results as in the session before. The choppy noise apparently starts as soon as there was a louder part in the audio stream. This noise changes is pitch all the time along with the music. The Speakers don't seem to have that noise, but I can't really be sure because the building where I live in is not suitable to test them longer at full volume, at least not at this time of day.
Still haven't reproduced the aforementioned kernel panic.
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By the way, the ALSA subsystem is not sparse-clean if CF="-D__CHECK_ENDIAN__" is specified in the make command line. Sparse gets nervous about __bitwise types being used as integers.