Subject: Re: USB feedback wanted
To: Bill Sommerfeld <email@example.com>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
Date: 06/30/1998 13:20:08
>What if I have multiple ostensibly "identical" (but not
>interchangeable) devices plugged into the bus... How do I nail down
>the configuration so that the mapping from device-driver minor numbers
>to physical devices remains the same? even if I temporarily
>plug/unplug yet another device?
>Think of a monophonic speaker. Assume I have two plugged in as my
>`left' and `right' stereo channels. if I just let the mapping
>"float", what happens if I add a third speaker, and it happens to come
>"before" the other two in the autoconfig order? does the new one
>become "left", the old "left" become "right" and the old "right" get
>nothing at all?
If you think that's bad, wait till you try it with USB Ethernet
Trying to make the kernel automagically "get it right" , using only
bus-specific locators, when you can pull out, change, and reorder
devices "on the fly", seems like a lose to me.
The same problem comes up with PCMCIA, too...