Re: [PATCH 1/1] PXAFB: Support for backlight control

From: Rodolfo Giometti
Date: Wed Feb 21 2007 - 11:12:21 EST

On Wed, Feb 21, 2007 at 06:00:37PM +0200, Paul Sokolovsky wrote:
> On the other hand, there's already
> drivers/video/backlight/backlight.c which provides generic BL support,
> implemented using notifier callback for FB core. Moreover, there's

My patch _uses_ that support.

> corgi_bl.c driver which, contrary to its name is a generic driver for
> embedded/PDA device backlight. It essentially subclassses pretty
> abstract backlight.c, and provides good implementation for most BL
> implementation. What you really need to do to use it, is to supply
> single machine-dependent method, set_bl_intensity(). That method is
> usually <10 lines.

I see, but in this manner you need to make a complete file for each
board, while with my patch you can just put few lines into machine's
definition file (a struct and 2 functions).

> With this in mind, adhoc backlight handlers in pxafb and few other
> drivers are artifacts of older times. And it's sad they are tried to
> be resurrected instead of being removed.

IMHO, the actual backlight support is not so much, infact I'd like to
generalize it to support also backlighted keyboards (or input
devices). :)




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