diff options
| -rw-r--r-- | drivers/base/power/main.c | 85 |
1 files changed, 79 insertions, 6 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 4209140..04bcb11 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -246,6 +246,62 @@ static void dpm_wait_for_children(struct device *dev, bool async) device_for_each_child(dev, &async, dpm_wait_fn); } +static void dpm_wait_for_suppliers(struct device *dev, bool async) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + /* + * If the supplier goes away right after we've checked the link to it, + * we'll wait for its completion to change the state, but that's fine, + * because the only things that will block as a result are the SRCU + * callbacks freeing the link objects for the links in the list we're + * walking. + */ + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + if (READ_ONCE(link->status) != DL_STATE_DORMANT) + dpm_wait(link->supplier, async); + + device_links_read_unlock(idx); +} + +static void dpm_wait_for_superior(struct device *dev, bool async) +{ + dpm_wait(dev->parent, async); + dpm_wait_for_suppliers(dev, async); +} + +static void dpm_wait_for_consumers(struct device *dev, bool async) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + /* + * The status of a device link can only be changed from "dormant" by a + * probe, but that cannot happen during system suspend/resume. In + * theory it can change to "dormant" at that time, but then it is + * reasonable to wait for the target device anyway (eg. if it goes + * away, it's better to wait for it to go away completely and then + * continue instead of trying to continue in parallel with its + * unregistration). + */ + list_for_each_entry_rcu(link, &dev->links.consumers, s_node) + if (READ_ONCE(link->status) != DL_STATE_DORMANT) + dpm_wait(link->consumer, async); + + device_links_read_unlock(idx); +} + +static void dpm_wait_for_subordinate(struct device *dev, bool async) +{ + dpm_wait_for_children(dev, async); + dpm_wait_for_consumers(dev, async); +} + /** * pm_op - Return the PM operation appropriate for given PM event. * @ops: PM operations to choose from. @@ -490,7 +546,7 @@ static int device_resume_noirq(struct device *dev, pm_message_t state, bool asyn if (!dev->power.is_noirq_suspended) goto Out; - dpm_wait(dev->parent, async); + dpm_wait_for_superior(dev, async); if (dev->pm_domain) { info = "noirq power domain "; @@ -620,7 +676,7 @@ static int device_resume_early(struct device *dev, pm_message_t state, bool asyn if (!dev->power.is_late_suspended) goto Out; - dpm_wait(dev->parent, async); + dpm_wait_for_superior(dev, async); if (dev->pm_domain) { info = "early power domain "; @@ -752,7 +808,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) goto Complete; } - dpm_wait(dev->parent, async); + dpm_wait_for_superior(dev, async); dpm_watchdog_set(&wd, dev); device_lock(dev); @@ -1040,7 +1096,7 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a if (dev->power.syscore || dev->power.direct_complete) goto Complete; - dpm_wait_for_children(dev, async); + dpm_wait_for_subordinate(dev, async); if (dev->pm_domain) { info = "noirq power domain "; @@ -1187,7 +1243,7 @@ static int __device_suspend_late(struct device *dev, pm_message_t state, bool as if (dev->power.syscore || dev->power.direct_complete) goto Complete; - dpm_wait_for_children(dev, async); + dpm_wait_for_subordinate(dev, async); if (dev->pm_domain) { info = "late power domain "; @@ -1344,6 +1400,22 @@ static int legacy_suspend(struct device *dev, pm_message_t state, return error; } +static void dpm_clear_suppliers_direct_complete(struct device *dev) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { + spin_lock_irq(&link->supplier->power.lock); + link->supplier->power.direct_complete = false; + spin_unlock_irq(&link->supplier->power.lock); + } + + device_links_read_unlock(idx); +} + /** * device_suspend - Execute "suspend" callbacks for given device. * @dev: Device to handle. @@ -1360,7 +1432,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) TRACE_DEVICE(dev); TRACE_SUSPEND(0); - dpm_wait_for_children(dev, async); + dpm_wait_for_subordinate(dev, async); if (async_error) goto Complete; @@ -1456,6 +1528,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) spin_unlock_irq(&parent->power.lock); } + dpm_clear_suppliers_direct_complete(dev); } device_unlock(dev); |
