Yocto / USB touch interrupt to bump up clocks


I’m noticing touch latency on the first touch after a system has been idle for a while.

I’m thinking this can only be done with a physical interrupt line, but is there a way to associate a generic HID touch device (USB), so that a touch event raises the clocks to turbo?



This thread is pretty old but perhaps https://patchwork.kernel.org/patch/9128639/ (which is how this problem is solved on Android systems) might give you half of the solution. The other half is to modify the userspace code so that as soon as a touch event arrives something pokes the governor (?watch /dev/input?).

If you want to be more upstream friendly you could get the userspace code to switch between governors (perhaps swap temporarily to “performance” governor).