summaryrefslogtreecommitdiff
path: root/drivers/base/dd.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/base/dd.c')
-rw-r--r--drivers/base/dd.c79
1 files changed, 66 insertions, 13 deletions
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index d76cd97a98b6..a8b258e5407b 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -53,6 +53,19 @@ static LIST_HEAD(deferred_probe_pending_list);
static LIST_HEAD(deferred_probe_active_list);
static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
+static ssize_t deferred_probe_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ bool value;
+
+ mutex_lock(&deferred_probe_mutex);
+ value = !list_empty(&dev->p->deferred_probe);
+ mutex_unlock(&deferred_probe_mutex);
+
+ return sprintf(buf, "%d\n", value);
+}
+DEVICE_ATTR_RO(deferred_probe);
+
/*
* In some cases, like suspend to RAM or hibernation, It might be reasonable
* to prohibit probing of devices as it could be unsafe.
@@ -244,6 +257,7 @@ static void driver_bound(struct device *dev)
__func__, dev_name(dev));
klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices);
+ device_links_driver_bound(dev);
device_pm_check_callbacks(dev);
@@ -338,6 +352,10 @@ static int really_probe(struct device *dev, struct device_driver *drv)
return ret;
}
+ ret = device_links_check_suppliers(dev);
+ if (ret)
+ 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));
@@ -416,6 +434,7 @@ probe_failed:
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
pinctrl_bind_failed:
+ device_links_no_driver(dev);
devres_release_all(dev);
driver_sysfs_remove(dev);
dev->driver = NULL;
@@ -508,6 +527,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
drv->bus->name, __func__, dev_name(dev), drv->name);
+ pm_runtime_get_suppliers(dev);
if (dev->parent)
pm_runtime_get_sync(dev->parent);
@@ -518,6 +538,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
if (dev->parent)
pm_runtime_put(dev->parent);
+ pm_runtime_put_suppliers(dev);
return ret;
}
@@ -772,7 +793,7 @@ EXPORT_SYMBOL_GPL(driver_attach);
* __device_release_driver() must be called with @dev lock held.
* When called for a USB interface, @dev->parent lock must be held as well.
*/
-static void __device_release_driver(struct device *dev)
+static void __device_release_driver(struct device *dev, struct device *parent)
{
struct device_driver *drv;
@@ -781,7 +802,27 @@ static void __device_release_driver(struct device *dev)
if (driver_allows_async_probing(drv))
async_synchronize_full();
+ while (device_links_busy(dev)) {
+ device_unlock(dev);
+ if (parent)
+ device_unlock(parent);
+
+ device_links_unbind_consumers(dev);
+ if (parent)
+ device_lock(parent);
+
+ device_lock(dev);
+ /*
+ * A concurrent invocation of the same function might
+ * have released the driver successfully while this one
+ * was waiting, so check for that.
+ */
+ if (dev->driver != drv)
+ return;
+ }
+
pm_runtime_get_sync(dev);
+ pm_runtime_clean_up_links(dev);
driver_sysfs_remove(dev);
@@ -796,6 +837,8 @@ static void __device_release_driver(struct device *dev)
dev->bus->remove(dev);
else if (drv->remove)
drv->remove(dev);
+
+ device_links_driver_cleanup(dev);
devres_release_all(dev);
dev->driver = NULL;
dev_set_drvdata(dev, NULL);
@@ -812,12 +855,32 @@ static void __device_release_driver(struct device *dev)
}
}
+void device_release_driver_internal(struct device *dev,
+ struct device_driver *drv,
+ struct device *parent)
+{
+ if (parent)
+ device_lock(parent);
+
+ device_lock(dev);
+ if (!drv || drv == dev->driver)
+ __device_release_driver(dev, parent);
+
+ device_unlock(dev);
+ if (parent)
+ device_unlock(parent);
+}
+
/**
* device_release_driver - manually detach device from driver.
* @dev: device.
*
* Manually detach device from driver.
* When called for a USB interface, @dev->parent lock must be held.
+ *
+ * If this function is to be called with @dev->parent lock held, ensure that
+ * the device's consumers are unbound in advance or that their locks can be
+ * acquired under the @dev->parent lock.
*/
void device_release_driver(struct device *dev)
{
@@ -826,9 +889,7 @@ void device_release_driver(struct device *dev)
* within their ->remove callback for the same device, they
* will deadlock right here.
*/
- device_lock(dev);
- __device_release_driver(dev);
- device_unlock(dev);
+ device_release_driver_internal(dev, NULL, NULL);
}
EXPORT_SYMBOL_GPL(device_release_driver);
@@ -853,15 +914,7 @@ void driver_detach(struct device_driver *drv)
dev = dev_prv->device;
get_device(dev);
spin_unlock(&drv->p->klist_devices.k_lock);
-
- if (dev->parent) /* Needed for USB */
- device_lock(dev->parent);
- device_lock(dev);
- if (dev->driver == drv)
- __device_release_driver(dev);
- device_unlock(dev);
- if (dev->parent)
- device_unlock(dev->parent);
+ device_release_driver_internal(dev, drv, dev->parent);
put_device(dev);
}
}