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path: root/drivers/base/power/main.c
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Diffstat (limited to 'drivers/base/power/main.c')
-rw-r--r--drivers/base/power/main.c87
1 files changed, 81 insertions, 6 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index eb474c882ebe..48c6294e9c34 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -131,6 +131,7 @@ void device_pm_add(struct device *dev)
dev_warn(dev, "parent %s should not be sleeping\n",
dev_name(dev->parent));
list_add_tail(&dev->power.entry, &dpm_list);
+ dev->power.in_dpm_list = true;
mutex_unlock(&dpm_list_mtx);
}
@@ -145,6 +146,7 @@ void device_pm_remove(struct device *dev)
complete_all(&dev->power.completion);
mutex_lock(&dpm_list_mtx);
list_del_init(&dev->power.entry);
+ dev->power.in_dpm_list = false;
mutex_unlock(&dpm_list_mtx);
device_wakeup_disable(dev);
pm_runtime_remove(dev);
@@ -244,6 +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.
@@ -488,7 +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 ";
@@ -618,7 +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 ";
@@ -750,7 +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);
@@ -1027,7 +1085,7 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a
TRACE_DEVICE(dev);
TRACE_SUSPEND(0);
- dpm_wait_for_children(dev, async);
+ dpm_wait_for_subordinate(dev, async);
if (async_error)
goto Complete;
@@ -1174,7 +1232,7 @@ static int __device_suspend_late(struct device *dev, pm_message_t state, bool as
__pm_runtime_disable(dev, false);
- dpm_wait_for_children(dev, async);
+ dpm_wait_for_subordinate(dev, async);
if (async_error)
goto Complete;
@@ -1342,6 +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.
@@ -1358,7 +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;
@@ -1454,6 +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);