Re: Git backlight subsystem tree

Greg KH
2007-02-08T21:24:52Z

On Thu, Feb 08, 2007 at 06:32:02PM +0000, James Simmons wrote:
> On Thu, 8 Feb 2007, Richard Purdie wrote:
>
> > On Thu, 2007-02-08 at 15:28 +0000, James Simmons wrote:
> > > I have some patches that move the backlight away from using the class
> > > stuff. The only problem is the patch requires all backlight devices
> > > to be linked to a real struct device. Right now the acpi backligths are
> > > not.
> >
> > Why would you want to do that?
> >
> > The whole point of having this is so that backlights appear as a
> > standard interface under /sys/class/backlight.
> >
> > An example of why standardised interfaces are good would be someone
> > writing an applet for a handheld to control the backlight brightness.
> > With the class in place, the applet can easily work with any backlight.
> > Without it, it has to be written for each backlight.
> >
> > So this is a very strong NAK but I'm curious why you'd want to do it...
>
> I CC Greg to explain. The backlight class didn't go away. The way it is
> handled is different.

Have a pointer to the patch so I can help explain better?

As a short summary, 'struct class_device' is going away. Using a
'struct device' in its place is what the conversion should have just
done, no functionality change otherwise.

thanks,

greg k-h