On Tue, 8 Mar 2005, Adam Belay wrote: > I'm not sure if I agree that a parent can be suspended without first suspending > its children. In general, a parent device can be lowered in power only if the > context and operation of the child devices are maintained. If the change in > state does not affect the operation of child devices, then it really isn't a > "suspend". This partly a question of definitions and usage. However, if a parent's change of state can be made transparent to the child device driver (i.e., the parent resumes automatically whenever the child driver tries to do anything), then why shouldn't the parent suspend itself without suspending the child? Consider a driver for a disk device, which has a "gendisk" child. The idea of suspending a gendisk doesn't really make sense, since a gendisk isn't a physical device. So the driver might want to spin down and suspend the physical disk without suspending the gendisk child. Alan Stern
