How would I enable the system to recognize that there is a TCA9545A four port I2C bus switch there and handle it? I see that there are drivers for the family but how would I enable it and where would it show up?
Hi, from hardware point, I2C is master-to-slave mode, master will send out the query to address of slave, and slave will give feedback if exist.
you may use the sysnode to access the GPIO pins.
please also check my comments in Topic 1041755,
How would I go about using sysnode? I am new to this level of interfacing (2 weeks)
you should check the gpio definitions: /kernel/kernel-4.4/include/dt-bindings/gpio/tegra186-gpio.h
about accessing GPIOs via sysnode,
connect to Jetson platform, and you are able to found the GPIO pin at below path.
to generate gpio220 name for example,
cd /sys/class/gpio echo 220 > export
set the pin direction and default value
cd /sys/class/gpio/gpio220 echo out > direction echo 1 > value
please read the L4T documentation for more details.
you may refer to https://elinux.org/Jetson_TX2 for guidance and tutorials.