On Sat, 12 Feb 2011, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rjw@xxxxxxx> > > The platform bus type is often used to handle Systems-on-a-Chip (SoC) > where all devices are represented by objects of type struct > platform_device. In those cases the same "platform" device driver > may be used with multiple different system configurations, but the > actions needed to put the devices it handles into a low-power state > and back into the full-power state may depend on the design of the > given SoC. The driver, however, cannot possibly include all the > information necessary for the power management of its device on all > the systems it is used with. Moreover, the device hierarchy in its > current form also is not suitable for representing this kind of > information. > > The patch below attempts to address this problem by introducing > objects of type struct dev_power_domain that can be used for > representing power domains within a SoC. Every struct > dev_power_domain object provides a sets of device power > management callbacks that can be used to perform what's needed for > device power management in addition to the operations carried out by > the device's driver and subsystem. > > Namely, if a struct dev_power_domain object is pointed to by the > pwr_domain field in a struct device, the callbacks provided by its > ops member will be executed in addition to the corresponding > callbacks provided by the device's subsystem and driver during all > power transitions. Overall this looks very good. > Index: linux-2.6/include/linux/pm.h > =================================================================== > --- linux-2.6.orig/include/linux/pm.h > +++ linux-2.6/include/linux/pm.h > @@ -463,6 +463,14 @@ struct dev_pm_info { > > extern void update_pm_runtime_accounting(struct device *dev); > > +/* > + * Power domains provide callbacks that are executed during system suspend, > + * hibernation, system resume and during runtime PM transitions along with > + * subsystem-level and driver-level callbacks. > + */ > +struct dev_power_domain { > + struct dev_pm_ops ops; > +}; I don't have a clear picture of how people are going to want to use these dev_power_domain structures. Should there be a void *priv; member as well? Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm