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From: Juergen Beisert <jbe@pengutronix.de>
To: linuxppc-dev@ozlabs.org
Date: Wed, 12 Nov 2008 11:51:44 +0100
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Subject: Using gpiolib to power off my system
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Hi list,

I want to use the gpiolib API in a routine that should poweroff the system=
=20
(MPC5200B). I register my poweroff routine in the define_machine() macro as:

[...]
=2Epower_off	=3D my_power_off,
[...]

In this routine I'm using gpio_request(...), gpio_direction_output(...) and=
=20
gpio_set_value(...) ---- but nothing happens.

When I set the GPIOs in the hard way (ioremap() + playing with the register=
s)=20
the system switches off as expected.

How to get some useful debug output at this late system state (printk does =
not=20
work anymore)?

Regards,
Juergen
=2D-=20
Dipl.-Ing. Juergen Beisert | http://www.pengutronix.de
=A0Pengutronix - Linux Solutions for Science and Industry
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