At Fri, 13 Jul 2007 16:51:31 +0200, Thibault Le Meur wrote: > > Hi, > > For the M-Audio Audiophile USB device I still see 3 tasks that could be done > to improve support under Alsa: > > 1- Remap the Alsa 'hardware pcm devices' > > Currently: > * hw:1,0 is bound to the Analog interface in playback mode but to the > Digital interface in capture mode > * hw:1,1 is bound to the Analog interface in capture mode but to the Digital > interface in playback mode > > It would be great if the one pcm device+subdevice was always linked to the > same interface (Analog or Digital) > Can anyone could point me to the piece of code that chooses the mapping > between the device physiscal interface and Alsa's pcm interface? I'll try to > see if I can fix this. In the case of usb-audio, it's a bit complicated. The streams are assigned automatically per USB descriptions. I think the easiest would be to mangle the PCM device number in alsa-lib USB-Audio.conf file. Maybe Clemens can give a better hint. > 2- Have the device able to act as a 4 channels-in + 4 channels-out combined > device under Jackd > I had no success in defining a multi pcm device and have it work under Jackd > (but this might be a Jackd issue). > > Just a question about this: in the "Multiple ICE1712 Sound Cards" tutorial, > it is said that : > "A change was made in alsa-lib-1.0.9rc1 which had the unintended effect of > preventing the pcm_multi plugin from working with jackd (or jackdmp) in > duplex mode" "To make it work it's necessary to remove the linking code > which was added in pcm_multi.c rev 1.89. It isn't needed here anyway. Here's > a patch(http://www.sound-man.co.uk/linuxaudio/pcm_multi-patch) that removes > it from alsa-lib versions 1.0.10 to 1.0.13." > > Is it still true with current versions of alsa-lib? The problem with multi plugin and JACK was fixed on 1.0.14. > 3- Have a user interface to switch device_setup modes > This may be the hardest to do and I don't think I've got the required skills > to do this. Anyway, I would realy appreciate any information (or existing > piece of code) about the following: > * how to write a user interface which interacts with the kernel module > * forcing a reinitialization of the snd-usb-audio module without > unprobing/reprobing the kernel module Well, the best would be to allow the driver to change the running mode on the fly without device_setup option. But this seems requring fairly big change because of the current framework of the usb-audio driver. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
