gcadapter_oc_kmod
Kernel module for overclocking (setting the polling rate of) the Nintendo Wii U/Mayflash GameCube adapter.
The default overclock is from 125 hz -> 500 hz.
Requirements
linux + linux-headers
Building and running
make to build gcadapter_oc.ko
make clean to clean up
sudo insmod gcadapter_oc.ko to load the module into the running kernel (you'll need to replug the adapter to get any effect, check dmesg)
sudo rmmod gcadapter_oc.ko to unload the module (restores the default rate of 125 hz)
Changing the polling rate
Polling rate is set according to the bInterval value in the USB endpoint descriptor. The value sets the rate in ms, so you can for example set the rate to 4 to get (1000 / 4) 250 hz.
You can change the rate by using the kernel parameter gcadapter_oc.rate=<rate> (if installed), passing the rate to sudo insmod or going into /sys/module/gcadapter_oc/parameters and echo-ing the value.