Re: Future devfs plans

[Erik Steffl <steffl@bigfoot.com>]

Andreas Jellinghaus wrote:
> On Mon, 26 Jul 2004 00:34:51 +0000, Ramón Rey Vicente wrote:
> 
>>With udev you can do that, and without important bugs :). And the more
>>important thing is _udev is in active development_
> 
> 
> devfs has the "open /dev/somefile" to load $somedriver
> mechanism. it is said to be racy, as far as I know.
> 
> udev works very differently. mostly, the idea is kernel detects hardware,
> kernel calls hotplug, hotplug loads driver, driver registers device
> structure in kernel, kernel calls hotplug for the new device, udev creates
> the device in /dev.
> 
> with this mechanism, the kernel always has all drivers for hardware
> currently available loaded, and udev provides the /dev devices.
> 
> devfs allowes you to not have the driver loaded till you try to use it.
> so udev _cannot_ do what devfs does.
> 
> still I agree that the way kernel/hotplug/udev work is much better and
> supporting the old style devfs works is not necessary. but please be
> honest about the differences.

   which means that now iPod automatically connects to firewire (and 
looses info on random tracks, sometime some other settings), instead of 
only connecting when I try to actually access it (the device).

   it looks like there is no user level (end user, not admin) control on 
when the device drivers are loaded anymore - or is there?

   Is there any way to load drivers on demand (obviously it's not job of 
udev but whose job it is?). What about unloading them - I unmount the 
disk and i think the iPod is disconnecred but it still says connected - 
is there any way to disconnect it (I guess similar problems arise with 
other hotplug devices)

	erik