diff options
Diffstat (limited to 'drivers/base/power/main.c')
| -rw-r--r-- | drivers/base/power/main.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 1710c26ba..6e7c3ccea 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -125,6 +125,7 @@ void device_pm_add(struct device *dev) { pr_debug("PM: Adding info for %s:%s\n", dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); + device_pm_check_callbacks(dev); mutex_lock(&dpm_list_mtx); if (dev->parent && dev->parent->power.is_prepared) dev_warn(dev, "parent %s should not be sleeping\n", @@ -147,6 +148,7 @@ void device_pm_remove(struct device *dev) mutex_unlock(&dpm_list_mtx); device_wakeup_disable(dev); pm_runtime_remove(dev); + device_pm_check_callbacks(dev); } /** @@ -963,6 +965,9 @@ void dpm_complete(pm_message_t state) } list_splice(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); + + /* Allow device probing and trigger re-probing of deferred devices */ + device_unblock_probing(); trace_suspend_resume(TPS("dpm_complete"), state.event, false); } @@ -1569,6 +1574,11 @@ static int device_prepare(struct device *dev, pm_message_t state) dev->power.wakeup_path = device_may_wakeup(dev); + if (dev->power.no_pm_callbacks) { + ret = 1; /* Let device go direct_complete */ + goto unlock; + } + if (dev->pm_domain) { info = "preparing power domain "; callback = dev->pm_domain->ops.prepare; @@ -1591,6 +1601,7 @@ static int device_prepare(struct device *dev, pm_message_t state) if (callback) ret = callback(dev); +unlock: device_unlock(dev); if (ret < 0) { @@ -1624,6 +1635,20 @@ int dpm_prepare(pm_message_t state) trace_suspend_resume(TPS("dpm_prepare"), state.event, true); might_sleep(); + /* + * Give a chance for the known devices to complete their probes, before + * disable probing of devices. This sync point is important at least + * at boot time + hibernation restore. + */ + wait_for_device_probe(); + /* + * It is unsafe if probing of devices will happen during suspend or + * hibernation and system behavior will be unpredictable in this case. + * So, let's prohibit device's probing here and defer their probes + * instead. The normal behavior will be restored in dpm_complete(). + */ + device_block_probing(); + mutex_lock(&dpm_list_mtx); while (!list_empty(&dpm_list)) { struct device *dev = to_device(dpm_list.next); @@ -1719,3 +1744,30 @@ void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *)) device_pm_unlock(); } EXPORT_SYMBOL_GPL(dpm_for_each_dev); + +static bool pm_ops_is_empty(const struct dev_pm_ops *ops) +{ + if (!ops) + return true; + + return !ops->prepare && + !ops->suspend && + !ops->suspend_late && + !ops->suspend_noirq && + !ops->resume_noirq && + !ops->resume_early && + !ops->resume && + !ops->complete; +} + +void device_pm_check_callbacks(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + dev->power.no_pm_callbacks = + (!dev->bus || pm_ops_is_empty(dev->bus->pm)) && + (!dev->class || pm_ops_is_empty(dev->class->pm)) && + (!dev->type || pm_ops_is_empty(dev->type->pm)) && + (!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) && + (!dev->driver || pm_ops_is_empty(dev->driver->pm)); + spin_unlock_irq(&dev->power.lock); +} |