From: linux@prisktech.co.nz (Tony Prisk)
To: linux-arm-kernel@lists.infradead.org
Subject: GPIO sysfs 'default' values
Date: Thu, 21 Feb 2013 20:11:20 +1300 [thread overview]
Message-ID: <1361430680.10390.7.camel@gitbox> (raw)
Hi Grant, Linus.
I was testing our new gpio/pinctrl driver today and noticed something a
little weird.
I exported gpio0 via sysfs and echoed the direction value - it was 'in'.
This pin is used to control an LCD panel, and is actually in 'out' mode.
If I write 'in' to direction, it changes mode to 'in' and the panel
turns off. Setting it back to 'out' and value=0, and the panel turns on
again.
I noticed that I had no gpiochip->get_direction, so I added it, but the
result was the same.
Any idea what I've missed?
Regards
Tony Prisk
next reply other threads:[~2013-02-21 7:11 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-21 7:11 Tony Prisk [this message]
2013-02-21 7:27 ` GPIO sysfs 'default' values Tony Prisk
2013-02-21 7:37 ` Lothar Waßmann
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