diff options
Diffstat (limited to 'drivers/base/power/generic_ops.c')
| -rw-r--r-- | drivers/base/power/generic_ops.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c new file mode 100644 index 00000000000..4b29d498125 --- /dev/null +++ b/drivers/base/power/generic_ops.c @@ -0,0 +1,233 @@ +/* + * drivers/base/power/generic_ops.c - Generic PM callbacks for subsystems + * + * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include <linux/pm.h> +#include <linux/pm_runtime.h> + +#ifdef CONFIG_PM_RUNTIME +/** + * pm_generic_runtime_idle - Generic runtime idle callback for subsystems. + * @dev: Device to handle. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_idle(), execute it and return its error code, if nonzero. + * Otherwise, execute pm_runtime_suspend() for the device and return 0. + */ +int pm_generic_runtime_idle(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + if (pm && pm->runtime_idle) { + int ret = pm->runtime_idle(dev); + if (ret) + return ret; + } + + pm_runtime_suspend(dev); + return 0; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_idle); + +/** + * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems. + * @dev: Device to suspend. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_suspend(), execute it and return its error code. Otherwise, + * return -EINVAL. + */ +int pm_generic_runtime_suspend(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + ret = pm && pm->runtime_suspend ? pm->runtime_suspend(dev) : -EINVAL; + + return ret; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_suspend); + +/** + * pm_generic_runtime_resume - Generic runtime resume callback for subsystems. + * @dev: Device to resume. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_resume(), execute it and return its error code. Otherwise, + * return -EINVAL. + */ +int pm_generic_runtime_resume(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + ret = pm && pm->runtime_resume ? pm->runtime_resume(dev) : -EINVAL; + + return ret; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_resume); +#endif /* CONFIG_PM_RUNTIME */ + +#ifdef CONFIG_PM_SLEEP +/** + * __pm_generic_call - Generic suspend/freeze/poweroff/thaw subsystem callback. + * @dev: Device to handle. + * @event: PM transition of the system under way. + * + * If the device has not been suspended at run time, execute the + * suspend/freeze/poweroff/thaw callback provided by its driver, if defined, and + * return its error code. Otherwise, return zero. + */ +static int __pm_generic_call(struct device *dev, int event) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int (*callback)(struct device *); + + if (!pm || pm_runtime_suspended(dev)) + return 0; + + switch (event) { + case PM_EVENT_SUSPEND: + callback = pm->suspend; + break; + case PM_EVENT_FREEZE: + callback = pm->freeze; + break; + case PM_EVENT_HIBERNATE: + callback = pm->poweroff; + break; + case PM_EVENT_THAW: + callback = pm->thaw; + break; + default: + callback = NULL; + break; + } + + return callback ? callback(dev) : 0; +} + +/** + * pm_generic_suspend - Generic suspend callback for subsystems. + * @dev: Device to suspend. + */ +int pm_generic_suspend(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_SUSPEND); +} +EXPORT_SYMBOL_GPL(pm_generic_suspend); + +/** + * pm_generic_freeze - Generic freeze callback for subsystems. + * @dev: Device to freeze. + */ +int pm_generic_freeze(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_FREEZE); +} +EXPORT_SYMBOL_GPL(pm_generic_freeze); + +/** + * pm_generic_poweroff - Generic poweroff callback for subsystems. + * @dev: Device to handle. + */ +int pm_generic_poweroff(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_HIBERNATE); +} +EXPORT_SYMBOL_GPL(pm_generic_poweroff); + +/** + * pm_generic_thaw - Generic thaw callback for subsystems. + * @dev: Device to thaw. + */ +int pm_generic_thaw(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_THAW); +} +EXPORT_SYMBOL_GPL(pm_generic_thaw); + +/** + * __pm_generic_resume - Generic resume/restore callback for subsystems. + * @dev: Device to handle. + * @event: PM transition of the system under way. + * + * Execute the resume/resotre callback provided by the @dev's driver, if + * defined. If it returns 0, change the device's runtime PM status to 'active'. + * Return the callback's error code. + */ +static int __pm_generic_resume(struct device *dev, int event) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int (*callback)(struct device *); + int ret; + + if (!pm) + return 0; + + switch (event) { + case PM_EVENT_RESUME: + callback = pm->resume; + break; + case PM_EVENT_RESTORE: + callback = pm->restore; + break; + default: + callback = NULL; + break; + } + + if (!callback) + return 0; + + ret = callback(dev); + if (!ret) { + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + } + + return ret; +} + +/** + * pm_generic_resume - Generic resume callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_resume(struct device *dev) +{ + return __pm_generic_resume(dev, PM_EVENT_RESUME); +} +EXPORT_SYMBOL_GPL(pm_generic_resume); + +/** + * pm_generic_restore - Generic restore callback for subsystems. + * @dev: Device to restore. + */ +int pm_generic_restore(struct device *dev) +{ + return __pm_generic_resume(dev, PM_EVENT_RESTORE); +} +EXPORT_SYMBOL_GPL(pm_generic_restore); +#endif /* CONFIG_PM_SLEEP */ + +struct dev_pm_ops generic_subsys_pm_ops = { +#ifdef CONFIG_PM_SLEEP + .suspend = pm_generic_suspend, + .resume = pm_generic_resume, + .freeze = pm_generic_freeze, + .thaw = pm_generic_thaw, + .poweroff = pm_generic_poweroff, + .restore = pm_generic_restore, +#endif +#ifdef CONFIG_PM_RUNTIME + .runtime_suspend = pm_generic_runtime_suspend, + .runtime_resume = pm_generic_runtime_resume, + .runtime_idle = pm_generic_runtime_idle, +#endif +}; +EXPORT_SYMBOL_GPL(generic_subsys_pm_ops); |