[bug #44218] linuxgpio not working with raspberryPi 2. "Can't open gpioX/direction" : Permission denied. Fixed by little delay

[avrs-admin]

Rizlik rizlik@inventati.org
Mon 09 Feb 2015 11:31:25 PM UTC

Hi,

When trying to use avrdude with my raspberryPi2 using linuxgpio programmer I got:

"Can't open gpioX/direction" : Permission denied

When stepping the code in gdb the problem is not reproduced, so I thought that the problem is that avrdude try to change direction too fast after he exported the gpio pin.

Indeed adding a little delay before trying to switch direction fixes the problem. I attach a little patch that solve the problem for me.

Same problem is shown by

$ echo 2 > /sys/class/gpio/export; echo in > /sys/class/gpio2/direction

So isn't a problem of avrdude.

Hope it helps,
rizlik

file #33041: gpio_fix.patch

This issue was migrated from https://savannah.nongnu.org/bugs/?44218

[mcuee]

Yes #372 seems to be the same as #917 and #472.

• [bug #53279] Permission denied accessing /sys/class/gpio/gpioX/direction would leave pin exported #472
• Fix permission denied error in linuxgpio programmer #917

[mcuee]

I will mark this as duplicate of #386 and the fix is in #917.