[systemd-devel] [BUG] too many rfkill services

[Lennart Poettering]

On Thu, 20.11.14 13:34, Dan Williams (dcbw at redhat.com) wrote:

> That's normal behavior in the case of a platform rfkill device and a
> device-specific rfkill device.  The platform rfkill functionality can
> sometimes (often?) cut power to the device through BIOS and GPIOs, and
> it will drop off the USB or PCI bus.  But the device itself can also
> expose rfkill functionality through it's own drivers, that doesn't cause
> it to drop off the bus.  This is your case with the USB-based Bluetooth
> device and the BIOS-based platform killswitch.
> 
> Since the routing of all these rfkills is highly model specific, there
> is no way to know that the platform rfkill has an affect on any other
> device in a generic way.  That would have to be hardcoded into the
> kernel and would be pretty awful to maintain.

Hmm, so, currently we include the rfkill device name in the filename
we store in disk (combined with ID_PATH if it is known). For an rfkill
device that comes and goes and each time changes its name this
filename will not be stable. 

Is there any way how we can get some stable ID out of these devices,
in a way that allows multiple rfkill devices per USB device/interface?
I don't see how without kernel change.

If rfkill devices shall be reliably recognizable, then we need some
kind of sub-USB device stability...

Lennart

-- 
Lennart Poettering, Red Hat