<br><br><div class="gmail_quote">2010/8/11 Marek Vasut <span dir="ltr"><<a href="mailto:marek.vasut@gmail.com">marek.vasut@gmail.com</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Dne St 11. srpna 2010 12:51:25 Daniel Mack napsal(a):<br>
<div><div></div><div class="h5">> On Wed, Aug 11, 2010 at 02:46:15PM +0400, Yuri Ludkevich wrote:<br>
> > 2010/8/11 Daniel Mack <<a href="mailto:daniel@caiaq.de">daniel@caiaq.de</a>><br>
> ><br>
> > > On Wed, Aug 11, 2010 at 02:08:10PM +0400, Yuri Ludkevich wrote:<br>
> > > > 2010/8/11 Daniel Mack <<a href="mailto:daniel@caiaq.de">daniel@caiaq.de</a>><br>
> > > ><br>
> > > > > Yes, they are aliases to the signals without the "_2" suffix.<br>
> > > > > Quoting the PXA reference manual, chapter 5.3:<br>
> > > > ><br>
> > > > > GPIO<6_0>_2:<br>
> > > > ><br>
> > > > > General-Purpose IO Ports, second instantiation. The same signals as<br>
> > > > > GPIO<6:0>, but they are given separate names because they are<br>
> > ><br>
> > > configured<br>
> > ><br>
> > > > > on separate multi-function pins. The recommended configuration is<br>
> > > > > for both multi-function pin instantiations of these GPIOs not to<br>
> > > > > be configured simultaneously for GPIO functionality. The preferred<br>
> > > > > configuration for dual instantiation GPIO usage (that is, using<br>
> > > > > both GPIO<6:0> and GPIO<6:0>_2 functions) is to configure one<br>
> > > > > multi-function pin as a GPIO and the second multi-function pin<br>
> > > > > instantiation for an alternate function other than a GPIO<br>
> > > > > function. Configuring GPIO<6:0> to be present on two separate<br>
> > > > > multi-function pins is not recommended. However, when GPIO<6:0> is<br>
> > > > > configured as an output and both multi-function pin instantiations<br>
> > > > > are programmed for GPIO function, the primary and secondary<br>
> > > > > instantiation of the multi-function pins are both outputs from the<br>
> > > > > common GGPIO<6:0> signal. However, when GPIO<6:0> is<br>
> > ><br>
> > > an<br>
> > ><br>
> > > > > input, the inputs from both multi-function pin instantiations are<br>
> > > > > ORed together before the result is sent to the internal GPIO<6:0><br>
> > > > > input logic.<br>
> > > ><br>
> > > > Hmmm. I found with pxaregs tool what both GPIO4 and GPIO4_2<br>
> > > > configured as GPIO. May be this cause irq autodetection to fail?<br>
> > ><br>
> > > No - if you don't tell the driver which GPIO the interrupt line is<br>
> > > connected to, it can't know. But as the reference manual says, such<br>
> > > configurations should be avoided.<br>
> > ><br>
> > > You're welcome to come up with a patch :)<br>
> > ><br>
> > > Daniel<br>
> ><br>
> > I configure GPIO4 pin as nCS3 (alternate function #1) in colibri-pxa320.c<br>
> > and after that irq autoprobing found valid irq for UCB1400. So<br>
> > touchscreen now working just fine.<br>
><br>
> Good. Can you share a patch?<br>
<br>
</div></div>nCS3 is the chipselect for CPLD space actually (and the EXT chipselects). If<br>
it's configured as nCS3, you can write to the CPLD, but in case you don't need<br>
PCMCIA (and ext. chipselects), you should be ok either way.<br>
<br>
And as Dan said, don't mix GPIO4 and GPIO4_2 :)<br>
<br></blockquote><div>Yep. I know about CPLD. Our board do not use PCMCIA, only SD/MMC. So for us it should work.<br><br>But if someone wants to use both PCMCIA and touchscreen - how to configure this GPIOs properly?<br>
<br></div></div><br>