diff options
| -rw-r--r-- | drivers/base/power/main.c | 67 |
1 files changed, 63 insertions, 4 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index aec774c02ffc..7a767c8488dd 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -1236,6 +1236,41 @@ EXPORT_SYMBOL_GPL(dpm_resume_end); /*------------------------- Suspend routines -------------------------*/ +static bool dpm_leaf_device(struct device *dev) +{ + struct device *child; + + lockdep_assert_held(&dpm_list_mtx); + + child = device_find_any_child(dev); + if (child) { + put_device(child); + + return false; + } + + return true; +} + +static void dpm_async_suspend_parent(struct device *dev, async_func_t func) +{ + guard(mutex)(&dpm_list_mtx); + + /* + * If the device is suspended asynchronously and the parent's callback + * deletes both the device and the parent itself, the parent object may + * be freed while this function is running, so avoid that by checking + * if the device has been deleted already as the parent cannot be + * deleted before it. + */ + if (!device_pm_initialized(dev)) + return; + + /* Start processing the device's parent if it is "async". */ + if (dev->parent) + dpm_async_with_cleanup(dev->parent, func); +} + /** * resume_event - Return a "resume" message for given "suspend" sleep state. * @sleep_state: PM message representing a sleep state. @@ -1661,6 +1696,8 @@ static void dpm_clear_superiors_direct_complete(struct device *dev) device_links_read_unlock(idx); } +static void async_suspend(void *data, async_cookie_t cookie); + /** * device_suspend - Execute "suspend" callbacks for given device. * @dev: Device to handle. @@ -1790,7 +1827,13 @@ static int device_suspend(struct device *dev, pm_message_t state, bool async) complete_all(&dev->power.completion); TRACE_SUSPEND(error); - return error; + + if (error || async_error) + return error; + + dpm_async_suspend_parent(dev, async_suspend); + + return 0; } static void async_suspend(void *data, async_cookie_t cookie) @@ -1808,6 +1851,7 @@ static void async_suspend(void *data, async_cookie_t cookie) int dpm_suspend(pm_message_t state) { ktime_t starttime = ktime_get(); + struct device *dev; int error = 0; trace_suspend_resume(TPS("dpm_suspend"), state.event, true); @@ -1821,12 +1865,21 @@ int dpm_suspend(pm_message_t state) mutex_lock(&dpm_list_mtx); + /* + * Start processing "async" leaf devices upfront so they don't need to + * wait for the "sync" devices they don't depend on. + */ + list_for_each_entry_reverse(dev, &dpm_prepared_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_leaf_device(dev)) + dpm_async_with_cleanup(dev, async_suspend); + } + while (!list_empty(&dpm_prepared_list)) { - struct device *dev = to_device(dpm_prepared_list.prev); + dev = to_device(dpm_prepared_list.prev); list_move(&dev->power.entry, &dpm_suspended_list); - dpm_clear_async_state(dev); if (dpm_async_fn(dev, async_suspend)) continue; @@ -1840,8 +1893,14 @@ int dpm_suspend(pm_message_t state) mutex_lock(&dpm_list_mtx); - if (error || async_error) + if (error || async_error) { + /* + * Move all devices to the target list to resume them + * properly. + */ + list_splice(&dpm_prepared_list, &dpm_suspended_list); break; + } } mutex_unlock(&dpm_list_mtx); |