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Re: (Semi-random) thoughts on device tree structure and devfs

On Tue, Mar 09, 2010 at 04:10:47PM +0000, Iain Hibbert wrote:
> On Tue, 9 Mar 2010, David Young wrote:
> > On Tue, Mar 09, 2010 at 08:09:57AM +0000, Iain Hibbert wrote:
> > > (I say "device" rather than disk because I know that Bluetooth controllers
> > > work this way - you can't get the BDADDR until it is up and running)
> >
> > I don't understand why the intrinsic properties cannot be found out in
> > the match routine, or why waiting for several queries is a problem.
> Well, in the case of bt3c(4) it needs to load firmware before you can talk
> to it and find out the BDADDR.  So, you also need to access the disk
> before it configures..  I don't think the boot up sequence can handle this
> scenario as yet?  In that case, the firmware is loaded when the device is
> enabled (/etc/rc), not during autoconfig.

I guess that you could split bt3c(4) into upper & lower drivers.  The
upper driver's responsibility is to load the firmware and to match and
attach an instance of the lower driver.


David Young             OJC Technologies      Urbana, IL * (217) 278-3933

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