The generic PM domains (genpd) framework in the kernel provides a way of grouping devices together that have common power management (PM) operations. It is commonly used to represent hardware power domains (a.k.a power islands) that share a common voltage rail, but can also be used more generically. The genpd framework is also tighly coupled with the runtime power-management framework (runtime PM) which manages idle power states of individual devices.
This talk will give an overview of genpd, its common uses, how it interacts with hardware power domains, runtime PM, and how device driver writers interact with it through the runtime PM framework.
Kevin Hilman, Baylibre