Libgpiod tools control tegra-gpio failed

Hi,
I used libgpiod tool(v1.4.3) to test the GPIO12 on Jetson Nano, and I can’t change the output value of GPIO12 with command gpioset. While I connect a PCA9555 chip to I2C interface of Jetson Nano. The gpioset command can change the output value of PCA9555 GPIO.
GPIO12:
gpioset /dev/gpiochip0 194 1
gpioset /dev/gpiochip0 194 0
PCA9555:
gpioset /dev/gpiochip1 0 1
gpioset /dev/gpiochip1 0 0

hello ainolike,

may I know which JetPack release you’re working with, thanks

JetPack-4.6

hello ainolike,

how about using sysfs to toggle this pin,
$ cd /sys/class/gpio
# echo 194 > export
# cd gpio194
# echo out > direction && echo 1 > value

This method has no problem.

Hi JerryChange,
In my application I want to use the method of operating /dev/gpiochip0 just like gpioset. Do you have any idears?

hello ainolike,

I’ve tried on Nano platform, and it’s able to toggle the GPIO12 with libgpiod.
for example,

# gpioset gpiochip0 194=0
# gpioget gpiochip0 194
0
# gpioset gpiochip0 194=1
# gpioget gpiochip0 194
1

Hi JerryChange,
I try on both Jetson Nano Developer Kit and our own designed board with the same Jetson Nano module. This problem only occurs on our own designed board.

hello ainolike,

you should check Jetson Nano Product Design Guide to review the board design, thanks

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.