diff options
Diffstat (limited to 'drivers/base/power/runtime.c')
| -rw-r--r-- | drivers/base/power/runtime.c | 154 |
1 files changed, 106 insertions, 48 deletions
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index c55a7c70bc1a..f835b85bd4d9 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -19,10 +19,24 @@ typedef int (*pm_callback_t)(struct device *); +static inline pm_callback_t get_callback_ptr(const void *start, size_t offset) +{ + return *(pm_callback_t *)(start + offset); +} + +static pm_callback_t __rpm_get_driver_callback(struct device *dev, + size_t cb_offset) +{ + if (dev->driver && dev->driver->pm) + return get_callback_ptr(dev->driver->pm, cb_offset); + + return NULL; +} + static pm_callback_t __rpm_get_callback(struct device *dev, size_t cb_offset) { - pm_callback_t cb; const struct dev_pm_ops *ops; + pm_callback_t cb = NULL; if (dev->pm_domain) ops = &dev->pm_domain->ops; @@ -36,12 +50,10 @@ static pm_callback_t __rpm_get_callback(struct device *dev, size_t cb_offset) ops = NULL; if (ops) - cb = *(pm_callback_t *)((void *)ops + cb_offset); - else - cb = NULL; + cb = get_callback_ptr(ops, cb_offset); - if (!cb && dev->driver && dev->driver->pm) - cb = *(pm_callback_t *)((void *)dev->driver->pm + cb_offset); + if (!cb) + cb = __rpm_get_driver_callback(dev, cb_offset); return cb; } @@ -1191,10 +1203,12 @@ EXPORT_SYMBOL_GPL(__pm_runtime_resume); * * Return -EINVAL if runtime PM is disabled for @dev. * - * Otherwise, if the runtime PM status of @dev is %RPM_ACTIVE and either - * @ign_usage_count is %true or the runtime PM usage counter of @dev is not - * zero, increment the usage counter of @dev and return 1. Otherwise, return 0 - * without changing the usage counter. + * Otherwise, if its runtime PM status is %RPM_ACTIVE and (1) @ign_usage_count + * is set, or (2) @dev is not ignoring children and its active child count is + * nonero, or (3) the runtime PM usage counter of @dev is not zero, increment + * the usage counter of @dev and return 1. + * + * Otherwise, return 0 without changing the usage counter. * * If @ign_usage_count is %true, this function can be used to prevent suspending * the device when its runtime PM status is %RPM_ACTIVE. @@ -1216,7 +1230,8 @@ static int pm_runtime_get_conditional(struct device *dev, bool ign_usage_count) retval = -EINVAL; } else if (dev->power.runtime_status != RPM_ACTIVE) { retval = 0; - } else if (ign_usage_count) { + } else if (ign_usage_count || (!dev->power.ignore_children && + atomic_read(&dev->power.child_count) > 0)) { retval = 1; atomic_inc(&dev->power.usage_count); } else { @@ -1249,10 +1264,16 @@ EXPORT_SYMBOL_GPL(pm_runtime_get_if_active); * @dev: Target device. * * Increment the runtime PM usage counter of @dev if its runtime PM status is - * %RPM_ACTIVE and its runtime PM usage counter is greater than 0, in which case - * it returns 1. If the device is in a different state or its usage_count is 0, - * 0 is returned. -EINVAL is returned if runtime PM is disabled for the device, - * in which case also the usage_count will remain unmodified. + * %RPM_ACTIVE and its runtime PM usage counter is greater than 0 or it is not + * ignoring children and its active child count is nonzero. 1 is returned in + * this case. + * + * If @dev is in a different state or it is not in use (that is, its usage + * counter is 0, or it is ignoring children, or its active child count is 0), + * 0 is returned. + * + * -EINVAL is returned if runtime PM is disabled for the device, in which case + * also the usage counter of @dev is not updated. */ int pm_runtime_get_if_in_use(struct device *dev) { @@ -1827,7 +1848,7 @@ void pm_runtime_init(struct device *dev) dev->power.request_pending = false; dev->power.request = RPM_REQ_NONE; dev->power.deferred_resume = false; - dev->power.needs_force_resume = 0; + dev->power.needs_force_resume = false; INIT_WORK(&dev->power.work, pm_runtime_work); dev->power.timer_expires = 0; @@ -1854,6 +1875,11 @@ void pm_runtime_reinit(struct device *dev) pm_runtime_put(dev->parent); } } + /* + * Clear power.needs_force_resume in case it has been set by + * pm_runtime_force_suspend() invoked from a driver remove callback. + */ + dev->power.needs_force_resume = false; } /** @@ -1941,13 +1967,23 @@ void pm_runtime_drop_link(struct device_link *link) pm_request_idle(link->supplier); } -bool pm_runtime_need_not_resume(struct device *dev) +static pm_callback_t get_callback(struct device *dev, size_t cb_offset) { - return atomic_read(&dev->power.usage_count) <= 1 && - (atomic_read(&dev->power.child_count) == 0 || - dev->power.ignore_children); + /* + * Setting power.strict_midlayer means that the middle layer + * code does not want its runtime PM callbacks to be invoked via + * pm_runtime_force_suspend() and pm_runtime_force_resume(), so + * return a direct pointer to the driver callback in that case. + */ + if (dev_pm_strict_midlayer_is_set(dev)) + return __rpm_get_driver_callback(dev, cb_offset); + + return __rpm_get_callback(dev, cb_offset); } +#define GET_CALLBACK(dev, callback) \ + get_callback(dev, offsetof(struct dev_pm_ops, callback)) + /** * pm_runtime_force_suspend - Force a device into suspend state if needed. * @dev: Device to suspend. @@ -1964,10 +2000,6 @@ bool pm_runtime_need_not_resume(struct device *dev) * sure the device is put into low power state and it should only be used during * system-wide PM transitions to sleep states. It assumes that the analogous * pm_runtime_force_resume() will be used to resume the device. - * - * Do not use with DPM_FLAG_SMART_SUSPEND as this can lead to an inconsistent - * state where this function has called the ->runtime_suspend callback but the - * PM core marks the driver as runtime active. */ int pm_runtime_force_suspend(struct device *dev) { @@ -1975,10 +2007,10 @@ int pm_runtime_force_suspend(struct device *dev) int ret; pm_runtime_disable(dev); - if (pm_runtime_status_suspended(dev)) + if (pm_runtime_status_suspended(dev) || dev->power.needs_force_resume) return 0; - callback = RPM_GET_CALLBACK(dev, runtime_suspend); + callback = GET_CALLBACK(dev, runtime_suspend); dev_pm_enable_wake_irq_check(dev, true); ret = callback ? callback(dev) : 0; @@ -1990,15 +2022,16 @@ int pm_runtime_force_suspend(struct device *dev) /* * If the device can stay in suspend after the system-wide transition * to the working state that will follow, drop the children counter of - * its parent, but set its status to RPM_SUSPENDED anyway in case this - * function will be called again for it in the meantime. + * its parent and the usage counters of its suppliers. Otherwise, set + * power.needs_force_resume to let pm_runtime_force_resume() know that + * the device needs to be taken care of and to prevent this function + * from handling the device again in case the device is passed to it + * once more subsequently. */ - if (pm_runtime_need_not_resume(dev)) { + if (pm_runtime_need_not_resume(dev)) pm_runtime_set_suspended(dev); - } else { - __update_runtime_status(dev, RPM_SUSPENDED); - dev->power.needs_force_resume = 1; - } + else + dev->power.needs_force_resume = true; return 0; @@ -2009,33 +2042,37 @@ err: } EXPORT_SYMBOL_GPL(pm_runtime_force_suspend); +#ifdef CONFIG_PM_SLEEP + /** * pm_runtime_force_resume - Force a device into resume state if needed. * @dev: Device to resume. * - * Prior invoking this function we expect the user to have brought the device - * into low power state by a call to pm_runtime_force_suspend(). Here we reverse - * those actions and bring the device into full power, if it is expected to be - * used on system resume. In the other case, we defer the resume to be managed - * via runtime PM. + * This function expects that either pm_runtime_force_suspend() has put the + * device into a low-power state prior to calling it, or the device had been + * runtime-suspended before the preceding system-wide suspend transition and it + * was left in suspend during that transition. * - * Typically this function may be invoked from a system resume callback. + * The actions carried out by pm_runtime_force_suspend(), or by a runtime + * suspend in general, are reversed and the device is brought back into full + * power if it is expected to be used on system resume, which is the case when + * its needs_force_resume flag is set or when its smart_suspend flag is set and + * its runtime PM status is "active". + * + * In other cases, the resume is deferred to be managed via runtime PM. + * + * Typically, this function may be invoked from a system resume callback. */ int pm_runtime_force_resume(struct device *dev) { int (*callback)(struct device *); int ret = 0; - if (!dev->power.needs_force_resume) + if (!dev->power.needs_force_resume && (!dev_pm_smart_suspend(dev) || + pm_runtime_status_suspended(dev))) goto out; - /* - * The value of the parent's children counter is correct already, so - * just update the status of the device. - */ - __update_runtime_status(dev, RPM_ACTIVE); - - callback = RPM_GET_CALLBACK(dev, runtime_resume); + callback = GET_CALLBACK(dev, runtime_resume); dev_pm_disable_wake_irq_check(dev, false); ret = callback ? callback(dev) : 0; @@ -2046,9 +2083,30 @@ int pm_runtime_force_resume(struct device *dev) } pm_runtime_mark_last_busy(dev); + out: - dev->power.needs_force_resume = 0; + /* + * The smart_suspend flag can be cleared here because it is not going + * to be necessary until the next system-wide suspend transition that + * will update it again. + */ + dev->power.smart_suspend = false; + /* + * Also clear needs_force_resume to make this function skip devices that + * have been seen by it once. + */ + dev->power.needs_force_resume = false; + pm_runtime_enable(dev); return ret; } EXPORT_SYMBOL_GPL(pm_runtime_force_resume); + +bool pm_runtime_need_not_resume(struct device *dev) +{ + return atomic_read(&dev->power.usage_count) <= 1 && + (atomic_read(&dev->power.child_count) == 0 || + dev->power.ignore_children); +} + +#endif /* CONFIG_PM_SLEEP */ |