GPIO expander


There has a I2C(tca9539) device for TX1 GPIO expansion.Currently, we know it could control using the command of Linux i2c tool, but we couldn’t apply this into our coding(c or c++ program).
It seems that TX1 may have the driver for this I2C IC, so we could modify the device tree, and we could use the GPIO function such like gpio_get_value/gpio_set_value for coding in userspace.
This idea is just what we guess.
Is this make sense? If it’s possible, what’s the relative file we should modify?


Hi Ray0420,

I’m not familiar with this. What you said does make sense and you can search “tca9539_77” or “tca9539_74” to understand how to set it in device tree.

Hi vickyy,

Thanks for your reply.