placeholder for GPIO based PWM Haptics Driver

Hi,

I am working on a platform which has a GPIO based Haptics Module driven using PWM signals. I am developing a GPIO client driver for the same. 

The design is as below

Haptics Driver --> gets duty-cycle, period --> calculates pwm signal required --> pass pwm to gpio --> drive the Haptics motor.

Where should I place the driver under Linux source Tree?

Thanks & Regards
Gururaja