[PATCH] ARM: gta02: Add gpio bank B quirk for hardware revision 5 and earlier

Pavel Machek pavel at ucw.cz
Mon Nov 30 07:31:41 EST 2009


On Sun 2009-11-29 11:56:51, Lars-Peter Clausen wrote:
> Pavel Machek wrote:
> > Hi!
> >
> >> On gta02 hardware revision 5 and earlier the basis resistors for
> >> transistors of the leds are missing and reading their gpio pin
> >> status will always return 0. So we have to shadow the led states
> >> in software. This is done by "hijacking" the gpio accessor
> >> functions for bank B.
> >
> > Should that be done in LED driver, instead? Pave
> Hi
> 
> Nope, that won't work. Every time a gpio on gpb is changed the leds
> will turn off. So we would have to ship a special version of each
> driver using a gpio pin form gpb. We certainly don't want to do that.

_Any_ GPIO pin change will turn off the LED? Wow, the hardware is
severely misdesigned then, ok. That means you do need to modify GPIO
:-(. You probably should state it clearly in the comments.
									Pavel
-- 
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