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Merge branches 'pm-sleep' and 'pm-runtime' into pm-core

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This commit is contained in:
Rafael J. Wysocki
2015-12-07 02:17:17 +01:00
parent 7b06a6d7bf 013c074f86 5de85b9d57
commit d89d7ff9ed
5 changed files with 90 additions and 7 deletions
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50
drivers/base/dd.c
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@@ -54,6 +54,13 @@ static LIST_HEAD(deferred_probe_active_list);
static struct workqueue_struct *deferred_wq;
static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
/*
* In some cases, like suspend to RAM or hibernation, It might be reasonable
* to prohibit probing of devices as it could be unsafe.
* Once defer_all_probes is true all drivers probes will be forcibly deferred.
*/
static bool defer_all_probes;
/*
* deferred_probe_work_func() - Retry probing devices in the active list.
*/
@@ -171,6 +178,30 @@ static void driver_deferred_probe_trigger(void)
queue_work(deferred_wq, &deferred_probe_work);
}
/**
* device_block_probing() - Block/defere device's probes
*
* It will disable probing of devices and defer their probes instead.
*/
void device_block_probing(void)
{
defer_all_probes = true;
/* sync with probes to avoid races. */
wait_for_device_probe();
}
/**
* device_unblock_probing() - Unblock/enable device's probes
*
* It will restore normal behavior and trigger re-probing of deferred
* devices.
*/
void device_unblock_probing(void)
{
defer_all_probes = false;
driver_deferred_probe_trigger();
}
/**
* deferred_probe_initcall() - Enable probing of deferred devices
*
@@ -277,9 +308,20 @@ static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
static int really_probe(struct device *dev, struct device_driver *drv)
{
int ret = 0;
int ret = -EPROBE_DEFER;
int local_trigger_count = atomic_read(&deferred_trigger_count);
if (defer_all_probes) {
/*
* Value of defer_all_probes can be set only by
* device_defer_all_probes_enable() which, in turn, will call
* wait_for_device_probe() right after that to avoid any races.
*/
dev_dbg(dev, "Driver %s force probe deferral\n", drv->name);
driver_deferred_probe_add(dev);
return ret;
}
atomic_inc(&probe_count);
pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
drv->bus->name, __func__, drv->name, dev_name(dev));
@@ -340,6 +382,7 @@ probe_failed:
dev_set_drvdata(dev, NULL);
if (dev->pm_domain && dev->pm_domain->dismiss)
dev->pm_domain->dismiss(dev);
pm_runtime_reinit(dev);
switch (ret) {
case -EPROBE_DEFER:
@@ -393,6 +436,10 @@ int driver_probe_done(void)
*/
void wait_for_device_probe(void)
{
/* wait for the deferred probe workqueue to finish */
if (driver_deferred_probe_enable)
flush_workqueue(deferred_wq);
/* wait for the known devices to complete their probing */
wait_event(probe_waitqueue, atomic_read(&probe_count) == 0);
async_synchronize_full();
@@ -695,6 +742,7 @@ static void __device_release_driver(struct device *dev)
dev_set_drvdata(dev, NULL);
if (dev->pm_domain && dev->pm_domain->dismiss)
dev->pm_domain->dismiss(dev);
pm_runtime_reinit(dev);
klist_remove(&dev->p->knode_driver);
if (dev->bus)