(more) devices without power management support: uvideo1 uaudio2 umidi0 umidi1 umidi2

[Matthias Petermann <mp%petermann-it.de@localhost>]

Hello everybody,

the original thread on this topic "Re: Devices without power management 
support: dm0 dm1 (LVM / Device Mapper prevents ACPI Sleep State 3)" is a 
bit older. I hope it is ok that I continue here because the topic seems 
very similar to me.

Now that my x230 has become my main computer via the docking station 
with NetBSD, a few other devices have noticed that apparently have no 
support for their power management in NetBSD.

These are:

* uvideo (a Logitech webcam in my case)
* uaudio (DSP from a Steinberg UR22mkII currently not functional under 
NetBSD)
* umidi (MIDI interface from a Steinberg UR22mkII)

I do not (currently) need these devices in NetBSD, but I would like to 
send the laptop to sleep regularly without having to disconnect the 
wiring beforehand.

So my first question would be: Is there a simple way to prevent the 
"detection" of the USB devices in question, so that they are not 
initialized by the kernel? I couldn't use it with that, but I could send 
the computer to sleep, which would be a great relief for me at the moment.

A functioning power management would of course be even better. Does 
anyone already work on this topic or do you know of a USB driver that I 
could take as a good example? I guess it won't be that easy with the 
Device Mapper (original thread), since there are real devices attached 
to it, the state of which definitely changes when the power supply is 
switched off.

Best regards
Matthias