Re: [PATCH] 2.5.14 IDE 56

benh
2002-05-07T17:19:30Z

> /driverfs/root/pci0/00:1f.4/usb_bus/000/
>
>and it wouldn't be impossible (or even necessarily very hard) to make an
>IDE controller export the "IDE device tree" the same way a USB controller
>now exports the "USB device tree".
>
>For things like hotplug etc, I think driverfs is eventually the only way
>to go, simply because it gives you the full (and unambiguous) path to
>_any_ device, and is completely bus-agnostic.
>
>But there is definitely a potential backwards-compatibility-issue.

One interesting thing here would be to have some optional link between
the bus-oriented device tree and the function-oriented tree (ie. devfs
or simply /dev). For example, an IDE node in driverfs could eventually
hold symlinks to the entries it provides in /dev when using devfs (or
just provide major/minor when not using devfs).

What do you think ?

One problem I've been faced with on ppc is to be able to match
a linux device with what the firmware (Open Firmware) thinks that
device is. The firmware view is bus-centered and it would be pretty
easy to provide some additional entries in driverfs that give the
OF fullpath of a given device. But then, the link between the actual
driver in driverfs and the "device" as used by, for example, the
filesystem isn't trivial.

Ben.