Re: [PATCH 2.6.8.1 0/2] leds: new class for led devices

[Robert Schwebel <robert@schwebel.de>]

John, 

On Thu, Sep 02, 2004 at 08:33:10PM +0000, John Lenz wrote:
> This is an attempt to provide an alternative to the current arm
> specific led interface. This arm interface does not integrate well
> with the device model and sysfs.

I have written a GPIO device class driver for the same purpose; before
this goes into the kernel I think we should try to merge your attempts
with mine.

On embedded systems you normally have several things which are similar
to LEDs; embedded processors have quite a lot of general purpose I/O
pins. Normally you want some of the pins being used from userspace (like
'echo 1 > /sys/class/gpio/gpio5/level'), others are used from device
drivers. My framework offers a request_gpio() function similar to
request_gpio(), so the kernel can administrate these ressources. 

I suppose it is not too difficult to unify our drivers in a way that the
base mechanism is more abstract then LEDs (a GPIO pin can also represent
a power switch or whatever) and still can support your LED levels. 

I'll pull the gpio patch out of my working tree and post it here for
discussion. 

Robert
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