IMX7 eval - Incorrect GPIO value on sysfs

Technical Support
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1

Our Colibri is running on the Toradex Image 2.7

We want to read the current state of an output pin to toggle it.
Reading an input value works fine but reading output values always returns 0 (on low_active returns 1).
Setting the output values works(LED)

Testing this on other environments worked as expected(RPI).

We tried GPIO1_IO2,6,7 on the eval board.

After export and set direction:

echo 1 > /sys/class/gpio/gpio7/value
cat /sys/class/gpio/gpio7/value              #returns 0
2

Please note the SION bit described in Section 8.2.3.2 of the iMX7 Reference Manual. Also have a look at this post. SION bit would have to be set for the below to work.

echo 1 > /sys/class/gpio/gpio7/value
cat /sys/class/gpio/gpio7/value              #returns 1