Turris Mox Moxtet bus GPIO expander

modulename: gpio-moxtet.ko

configname: CONFIG_GPIO_MOXTET

Linux Kernel Configuration
└─>Device Drivers
└─>GPIO Support
└─>SPI GPIO expanders
└─>Turris Mox Moxtet bus GPIO expander
In linux kernel since version 5.1 (release Date: 2019-05-05)  
Say yes here if you are building for the Turris Mox router.
This is the driver needed for configuring the GPIOs via the Moxtet
bus. For example the Mox module with SFP cage needs this driver
so that phylink can use corresponding GPIOs.

source code: