Using GPIO?

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Hi there,

Can't anybody point me in the right direction regarding usage of GPIO
ports under Linux?
I'm running on a PPC405EP, and when the kernel initialises, I get the
messages:

IBM gpio driver version 07.25.02
GPIO #0 at 0xc3070700

Hence the "ibm_ocp_gpio.c"/"ibm_gpio_miscdev" module gets loaded.
However, I then though the GPIO would be available through a
"/dev/gpio"-device, but this does not exist.

How to get any further?

Regards,
  Martin Egholm


Re: Using GPIO?
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Which version of the kernel are you using, and where did you get it?

You should probably ask this question at
http://lists.linuxppc.org/linuxppc-embedded /
after reviewing the archives there.

- Dan

Re: Using GPIO?
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I heard from a friend that since it is an misc-device, it should have
major number 10, and the driver states a minor number 185, so now I
should be able to create the device myself... I will get back with the
result...

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Kernel 2.4.21 from ELDK (as far as I recall). I haven't compiled a new
one myself - yet!

// Martin


Re: Using GPIO?
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And that worked! :-) I just created the device myself opened it, and
inspired by the "gpio_test" test-application I'm now able to control a
couple of attached LEDs and register user-input.
However, I need to poll the input-ports in order to get the event at the
moment. The next step is to lure how to register an interrupt-mechanism
handling this...

Thanks for all your help so far,
  Martin


Re: Using GPIO?
Hi, there - again...

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Is there a news-group associated with that mailing-list, as well?
I'd prefer that...

// Martin


Re: Using GPIO?
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There's a gateway between that list and
nntp://news.gmane.org/gmane.linux.ports.ppc.embedded

See http://gmane.org/ for how posts are authorized
(I find that site confusing and hard to read,
so be prepared to dig a bit).
- Dan

--
My technical stuff: http://kegel.com
My politics: see http://www.misleader.org for examples of why I'm for regime
We've slightly trimmed the long signature. Click to see the full one.
Re: Using GPIO?
Quoted text here. Click to load it

There's a gateway between that list and
nntp://news.gmane.org/gmane.linux.ports.ppc.embedded

See http://gmane.org/ for how posts are authorized
(I find that site confusing and hard to read,
so be prepared to dig a bit).
- Dan

--
My technical stuff: http://kegel.com
My politics: see http://www.misleader.org for examples of why I'm for regime
We've slightly trimmed the long signature. Click to see the full one.

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