@@ -228,3 +228,24 @@ void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd)
device_pm_check_callbacks(dev);
}
EXPORT_SYMBOL_GPL(dev_pm_domain_set);
+
+/**
+ * dev_pm_domain_set_performance_state - Request a new performance state.
+ * @dev: The device to make the request for.
+ * @state: Target performance state for the device.
+ *
+ * This function should be called when a new performance state needs to be
+ * requested for a device that is attached to a PM domain. Note that, the
+ * support for performance scaling for PM domains is optional.
+ *
+ * Returns 0 on success and when performance scaling isn't supported, negative
+ * error code on failure.
+ */
+int dev_pm_domain_set_performance_state(struct device *dev, unsigned int state)
+{
+ if (dev->pm_domain && dev->pm_domain->set_performance_state)
+ return dev->pm_domain->set_performance_state(dev, state);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dev_pm_domain_set_performance_state);
@@ -719,6 +719,7 @@ extern void dev_pm_put_subsys_data(struct device *dev);
* @activate: Called before executing probe routines for bus types and drivers.
* @sync: Called after successful driver probe.
* @dismiss: Called after unsuccessful driver probe and after driver removal.
+ * @set_performance_state: Called to request a new performance state.
*
* Power domains provide callbacks that are executed during system suspend,
* hibernation, system resume and during runtime PM transitions instead of
@@ -731,6 +732,7 @@ struct dev_pm_domain {
int (*activate)(struct device *dev);
void (*sync)(struct device *dev);
void (*dismiss)(struct device *dev);
+ int (*set_performance_state)(struct device *dev, unsigned int state);
};
/*
@@ -435,6 +435,7 @@ struct device *dev_pm_domain_attach_by_name(struct device *dev,
void dev_pm_domain_detach(struct device *dev, bool power_off);
int dev_pm_domain_start(struct device *dev);
void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd);
+int dev_pm_domain_set_performance_state(struct device *dev, unsigned int state);
#else
static inline int dev_pm_domain_attach(struct device *dev, bool power_on)
{
@@ -457,6 +458,11 @@ static inline int dev_pm_domain_start(struct device *dev)
}
static inline void dev_pm_domain_set(struct device *dev,
struct dev_pm_domain *pd) {}
+static inline int dev_pm_domain_set_performance_state(struct device *dev,
+ unsigned int state)
+{
+ return 0;
+}
#endif
#endif /* _LINUX_PM_DOMAIN_H */
The generic PM domain is currently the only PM domain variant that supports performance scaling. To allow performance scaling to be supported through a common interface, let's add an optional callback ->set_performance_state(), in the struct dev_pm_domain. Moreover, let's add a function, dev_pm_domain_set_performance_state(), that may be called by consumers to request a new performance state for a device through its PM domain. Note that, in most cases it's preferred that a consumer use the OPP library to request a new performance state for its device. Although, this requires some additional changes to be supported, which are being implemented from subsequent changes. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> --- drivers/base/power/common.c | 21 +++++++++++++++++++++ include/linux/pm.h | 2 ++ include/linux/pm_domain.h | 6 ++++++ 3 files changed, 29 insertions(+)