GPIO stopped working after upgrade to DEY 2.2-r3

Upgraded from DEY 2.2-r1 to DEY 2.2-r2 and GPIO has stopped working. Writing value to /sys/class/gpio/gpio5/value does cause value to be written to device.

DEY-2.4-r1 is the latest release, and the problem could be due to the differences in device tree? Perhaps this GPIO is used by something else now? I would explicitly define it as GPIO there.

The four gpio we use were missing after the upgrade to 2.2-r3. I had to export each of them (e.g., echo 5 > /sys/class/gpio/export).
At this point, I can write to the gpio (e.g., echo 1 > /sys/class/gpio/gpio5/value) nothing happens.

I now suspect the problem is related to the fact that when I try to write I2C_SLAVE to /dev/i2c-0 while preparing to read a value, I get errno 6 “No such device or address”

do you see /dev/i2c-0 with ls ? Have you tried running tests from https://www.digi.com/resources/documentation/digidocs/90002285/#reference/bsp/v4-9_6ul/r_i2c_6ul.htm

Thank you for sticking with me…

I see /dev/i2c-0 under 2.2r3

ls -l /dev/i2c-0

crw-rw---- 1 root digiapix 89, 0 Apr 5 14:34 /dev/i2c-0
It differs from 2.2r1 with group permits and ownership

ls -la /dev/i2c-0

crw------- 1 root root 89, 0 Jan 1 1970 /dev/i2c-0

I have run i2cdetect, my device as at bus address 0x12. I see the device under r1, I do not see it under r3.

yes digi apix was introduced in dey-2.2r3:
https://www.digi.com/resources/documentation/digidocs/90002286/#reference/apix/r_apix_i2c.htm
There is an Eclipse based IDE now and i2c apix example there. give it a try.