From 7490e44239e60293bca0c2663229050c36c660c2 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Sat, 25 Sep 2010 23:35:15 +0200 Subject: PM / Runtime: Add no_callbacks flag Some devices, such as USB interfaces, cannot be power-managed independently of their parents, i.e., they cannot be put in low power while the parent remains at full power. This patch (as1425) creates a new "no_callbacks" flag, which tells the PM core not to invoke the runtime-PM callback routines for the such devices but instead to assume that the callbacks always succeed. In addition, the non-debugging runtime-PM sysfs attributes for the devices are removed, since they are pretty much meaningless. The advantage of this scheme comes not so much from avoiding the callbacks themselves, but rather from the fact that without the need for a process context in which to run the callbacks, more work can be done in interrupt context. Signed-off-by: Alan Stern Signed-off-by: Rafael J. Wysocki --- include/linux/pm.h | 7 +++++++ include/linux/pm_runtime.h | 2 ++ 2 files changed, 9 insertions(+) (limited to 'include') diff --git a/include/linux/pm.h b/include/linux/pm.h index 1abfe84f447d..abd81ffaba3c 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -41,6 +41,12 @@ extern void (*pm_power_off_prepare)(void); struct device; +#ifdef CONFIG_PM +extern const char power_group_name[]; /* = "power" */ +#else +#define power_group_name NULL +#endif + typedef struct pm_message { int event; } pm_message_t; @@ -475,6 +481,7 @@ struct dev_pm_info { unsigned int deferred_resume:1; unsigned int run_wake:1; unsigned int runtime_auto:1; + unsigned int no_callbacks:1; enum rpm_request request; enum rpm_status runtime_status; int runtime_error; diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index 5869d87fffac..8ca52f7c357e 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -36,6 +36,7 @@ extern void pm_runtime_forbid(struct device *dev); extern int pm_generic_runtime_idle(struct device *dev); extern int pm_generic_runtime_suspend(struct device *dev); extern int pm_generic_runtime_resume(struct device *dev); +extern void pm_runtime_no_callbacks(struct device *dev); static inline bool pm_children_suspended(struct device *dev) { @@ -110,6 +111,7 @@ static inline bool pm_runtime_suspended(struct device *dev) { return false; } static inline int pm_generic_runtime_idle(struct device *dev) { return 0; } static inline int pm_generic_runtime_suspend(struct device *dev) { return 0; } static inline int pm_generic_runtime_resume(struct device *dev) { return 0; } +static inline void pm_runtime_no_callbacks(struct device *dev) {} #endif /* !CONFIG_PM_RUNTIME */ -- cgit v1.2.3