colibri PXA320 and UCB1400 - touch screen troubles

[Yuri Ludkevich]

2010/8/11 Daniel Mack <daniel at caiaq.de>

> On Wed, Aug 11, 2010 at 02:08:10PM +0400, Yuri Ludkevich wrote:
> > 2010/8/11 Daniel Mack <daniel at caiaq.de>
> > > Yes, they are aliases to the signals without the "_2" suffix. Quoting
> > > the PXA reference manual, chapter 5.3:
> > >
> > > GPIO<6_0>_2:
> > >
> > > General-Purpose IO Ports, second instantiation. The same signals as
> > > GPIO<6:0>, but they are given separate names because they are
> configured
> > > on separate multi-function pins. The recommended configuration is for
> > > both multi-function pin instantiations of these GPIOs not to be
> > > configured simultaneously for GPIO functionality. The preferred
> > > configuration for dual instantiation GPIO usage (that is, using both
> > > GPIO<6:0> and GPIO<6:0>_2 functions) is to configure one multi-function
> > > pin as a GPIO and the second multi-function pin instantiation for an
> > > alternate function other than a GPIO function. Configuring GPIO<6:0> to
> > > be present on two separate multi-function pins is not recommended.
> > > However, when GPIO<6:0> is configured as an output and both
> > > multi-function pin instantiations are programmed for GPIO function, the
> > > primary and secondary instantiation of the multi-function pins are both
> > > outputs from the common GGPIO<6:0> signal. However, when GPIO<6:0> is
> an
> > > input, the inputs from both multi-function pin instantiations are ORed
> > > together before the result is sent to the internal GPIO<6:0> input
> > > logic.
> >
> > Hmmm. I found with pxaregs tool what both GPIO4 and GPIO4_2 configured as
> > GPIO. May be this cause irq autodetection to fail?
>
> No - if you don't tell the driver which GPIO the interrupt line is
> connected to, it can't know. But as the reference manual says, such
> configurations should be avoided.
>
> You're welcome to come up with a patch :)
>
> Daniel
>
> I configure GPIO4 pin as nCS3 (alternate function #1) in colibri-pxa320.c
and after that irq autoprobing found valid irq for UCB1400. So touchscreen
now working just fine.

May be I need to check other second instantiation pins for same thing?


PS: i am really sorry for may replaying.. i did not notice in time :(
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