On Thu, May 15, 2014 at 11:04 PM, Charles Steinkuehler <
[email protected]> wrote:

> On 5/15/2014 8:00 PM, Jason Kridner wrote:
> > I was able to get PWM output, but I'm struggling with GPIOs for some
> reason:
> >
> > root@beaglebone:~# dash -x `which config-pin` P9_18 out
> > .
> > .
> > .
> > + sudo -A su -c echo out > /sys/class/gpio/gpio4/direction
> > + echo_dbg echo gpio > /sys/devices/ocp.3/P9_18_pinmux.36/state
> > + [ -n  ]
> > + sudo -A su -c echo gpio > /sys/devices/ocp.3/P9_18_pinmux.36/state
> > + exit 0
> >
> > root@beaglebone:~# cat /sys/devices/ocp.3/P9_18_pinmux.36/state
> > gpio
> >
> > root@beaglebone:~# cat /sys/class/gpio/gpio4/direction
> > out
> >
> > root@beaglebone:~# fgrep P9_18
> /sys/devices/ocp.3/cape-universal.48/status
> > 11 P9_18                      4 IN  0
> >
> > Thoughts on why this still says "IN" and I don't see output?
>
> Hmm...probably because the cape-universal status under ocp represents
> the device tree that got exported, where all pins are GPIO inputs with
> appropriate pull up/down until you change them.  Since the settings are
> changed via the standard GPIO export sysfs files, this doesn't directly
> affect the device tree and likely isn't getting pulled back into the
> cape-universal sysfs entries.
>
> The pinmux helper and gpio sysfs entries should contain the proper
> values, and you should get correct results if you:
>
> config-pin -q p9.18
>

Fair enough:

beaglebone:~# config-pin -q p9.18
P9_18 Mode: gpio Direction: out Value: 1

Did some probing on the hardware and it looks fine. Guess I was having
another issue.


> --
> Charles Steinkuehler
> [email protected]
>
> --
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