Re: Registering GPIO LEDs

[Ian Pilcher <arequipeno@gmail.com>]

On 08/09/2013 12:26 AM, Kim, Milo wrote:
> It sounds you want to make the LED platform data flexible, right?

Yes, but only to the extent that it can handle this particular hardware.
I'm mostly concerned that something like a kernel upgrade, BIOS upgrade,
or loading additional modules will cause the "magic" GPIO numbers to
change.

> If you can use .dtb file in your system, it may be possible to use just offset
> values with GPIO controller, ich_gpio. Then, no hardcoded GPIO is required.

I'm fairly sure that device tree is not an option in most x86_64
distros.  (And the whole reason I'm doing this is to used such a
"mainstream" distro on this hardware, rather than the NAS vendor's
"firmware".)

For now, I think I'll go the kernel module route.  If necessary, user-
space can use sysfs to find the GPIO base of the ICH and pass it in.  I
suspect there's a way to do this entirely in the kernel, but I also
suspect that it's too much trouble to be worth the effort right now.

Thanks!

-- 
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Ian Pilcher                                         arequipeno@gmail.com
Sometimes there's nothing left to do but crash and burn...or die trying.
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