Mark Knecht wrote: > On Wed, Mar 19, 2008 at 1:52 PM, Cesare Marilungo > <cesare@xxxxxxxxxxxxxxxxx> wrote: > >> > >> Hi Mark, >> what if you want to control the order of two different devices both usb >> (and so both handled by the snd-usb-audio module? In particular I have >> an usb audio interface and usb keyboard which is recognized as an audio >> device (even if it doesn't have audio functionalities). The order >> switches randomly at each reboot. >> >> Thanks in advance, >> >> -c. >> >> > > Hi Cesare, > Good to hear from you. > > This was the subject of another thread I asked on (I think) this > list a week or two ago. Apparently there is no way to do this for > cards using identical drivers. I had an opportunity to put together a > machine using 3 HDSP9652's but I needed to know that order of the > cards and ensure that every time I booted that the order wouldn't > change. The response I got was that Alsa cannot handle this. > Yes, I remember that thread. But I thought my case would be addressable since the device are, at least, different. I also thought it should be quite common to have both an usb audio interface and an usb midi keyboard. > I did a little bit of study of how Windows does this for internal > cards. It appears that Windows pays attention to the resources the > device is using and keeps track of those. PCI bus and slot number. IRQ > assingment, etc. As loog as things don't change then it will comtinue > to use them the same way every day. > > For external devices it seems that the best way to do this in Linux > is though udev. Most external devices have a UUID of some type. If you > can identify the UUID and then build a udev rule it should work but > that's all way beyond my skill set. > I'll try this. Thanks. > Hope this helps, > Mark > > > All the best, -c. _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
