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Author Topic: problem with getting gpio working on 3.1  (Read 3268 times)

March 09, 2012, 09:54:41 pm
Im trying to get gpio to work on a 3.1 kernel
on boot im seeing the following messages
Code: [Select]
The GPIO_CFG4 is 0x55555,  not equal to 0x155555, maybe using by boot!
The GPIO_CFG5 is 0x15555555,  not equal to 0x0, maybe using by boot!
does anyone have any idea what this means?

also, ive built gpio support w/ sysfs into my kernel.
Id like to do be able to do something like the following...
Code: [Select]
$cd /sys/class/gpio

# this creates 'gpio7' directory, exports gpio[7] for use
$echo 7 > export

#setup gpio7 for output, and change its value to '0'/'low'
$echo "out" > gpio7/direction
$echo 0 > gpio7/value

#try to check value, should be zero, but value always stays 'high'/'1'
$cat gpio7/value
1
its not working, so somethings not right here; I cant change the gpio values, and that gpio error message during boot looks suspicious. can anyone please help me figure out whats going on here?
« Last Edit: March 09, 2012, 09:56:28 pm by changosurf »