I have a ConnectCore6UL-SBC (development kit) and I want to
power-off the MAX98089 audio codec.
The ConnectCore6UL-SBC Hardware Ref. Manual, lists the
I/O expander AUD_PWR/IO28 signal, as the control for the
MAX98089 power switch.
Default state is power on and I want to power off !
Please tell me, where can I change the state of this
I/O expander AUD_PWR/IO28 signal in the device tree.
Further, can I change the state of this signals to runtime,
over /sys/class/gpio or similar ?
The GPIOs on the IO Expander are not supported yet. Digi is currently developing the firmware for this Kinetis chip. Then they need to work on a GPIO driver for Linux. Once this is ready, the IO Expander will appear as another GPIO controller in Linux, with a certain GPIO base number.
The user will be able to control these GPIOs just like any other GPIO in the system.