5 files changed, 127 insertions, 11 deletions

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index ef522ae55480..5aee1c0169ea 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -333,9 +333,7 @@ static int match_name(struct device *dev, void *data)
 {
         const char *name = data;
 
-        if (strcmp(name, dev->bus_id) == 0)
-                return 1;
-        return 0;
+        return sysfs_streq(name, dev->bus_id);
 }
 
 /**
@@ -982,6 +980,56 @@ struct klist *bus_get_device_klist(struct bus_type *bus)
 }
 EXPORT_SYMBOL_GPL(bus_get_device_klist);
 
+/*
+ * Yes, this forcably breaks the klist abstraction temporarily.  It
+ * just wants to sort the klist, not change reference counts and
+ * take/drop locks rapidly in the process.  It does all this while
+ * holding the lock for the list, so objects can't otherwise be
+ * added/removed while we're swizzling.
+ */
+static void device_insertion_sort_klist(struct device *a, struct list_head *list,
+                                        int (*compare)(const struct device *a,
+                                                        const struct device *b))
+{
+        struct list_head *pos;
+        struct klist_node *n;
+        struct device *b;
+
+        list_for_each(pos, list) {
+                n = container_of(pos, struct klist_node, n_node);
+                b = container_of(n, struct device, knode_bus);
+                if (compare(a, b) <= 0) {
+                        list_move_tail(&a->knode_bus.n_node,
+                                       &b->knode_bus.n_node);
+                        return;
+                }
+        }
+        list_move_tail(&a->knode_bus.n_node, list);
+}
+
+void bus_sort_breadthfirst(struct bus_type *bus,
+                           int (*compare)(const struct device *a,
+                                          const struct device *b))
+{
+        LIST_HEAD(sorted_devices);
+        struct list_head *pos, *tmp;
+        struct klist_node *n;
+        struct device *dev;
+        struct klist *device_klist;
+
+        device_klist = bus_get_device_klist(bus);
+
+        spin_lock(&device_klist->k_lock);
+        list_for_each_safe(pos, tmp, &device_klist->k_list) {
+                n = container_of(pos, struct klist_node, n_node);
+                dev = container_of(n, struct device, knode_bus);
+                device_insertion_sort_klist(dev, &sorted_devices, compare);
+        }
+        list_splice(&sorted_devices, &device_klist->k_list);
+        spin_unlock(&device_klist->k_lock);
+}
+EXPORT_SYMBOL_GPL(bus_sort_breadthfirst);
+
 int __init buses_init(void)
 {
         bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL);
diff --git a/drivers/base/core.c b/drivers/base/core.c
index b98cb1416a2d..8c2cc2648f5a 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -523,11 +523,16 @@ static void klist_children_put(struct klist_node *n)
  * device_initialize - init device structure.
  * @dev: device.
  *
- * This prepares the device for use by other layers,
- * including adding it to the device hierarchy.
+ * This prepares the device for use by other layers by initializing
+ * its fields.
  * It is the first half of device_register(), if called by
- * that, though it can also be called separately, so one
- * may use @dev's fields (e.g. the refcount).
+ * that function, though it can also be called separately, so one
+ * may use @dev's fields. In particular, get_device()/put_device()
+ * may be used for reference counting of @dev after calling this
+ * function.
+ *
+ * NOTE: Use put_device() to give up your reference instead of freeing
+ * @dev directly once you have called this function.
  */
 void device_initialize(struct device *dev)
 {
@@ -835,9 +840,13 @@ static void device_remove_sys_dev_entry(struct device *dev)
  * This is part 2 of device_register(), though may be called
  * separately _iff_ device_initialize() has been called separately.
  *
- * This adds it to the kobject hierarchy via kobject_add(), adds it
+ * This adds @dev to the kobject hierarchy via kobject_add(), adds it
  * to the global and sibling lists for the device, then
  * adds it to the other relevant subsystems of the driver model.
+ *
+ * NOTE: _Never_ directly free @dev after calling this function, even
+ * if it returned an error! Always use put_device() to give up your
+ * reference instead.
  */
 int device_add(struct device *dev)
 {
@@ -965,6 +974,10 @@ done:
  * I.e. you should only call the two helpers separately if
  * have a clearly defined need to use and refcount the device
  * before it is added to the hierarchy.
+ *
+ * NOTE: _Never_ directly free @dev after calling this function, even
+ * if it returned an error! Always use put_device() to give up the
+ * reference initialized in this function instead.
  */
 int device_register(struct device *dev)
 {
@@ -1243,7 +1256,7 @@ struct device *device_create_vargs(struct class *class, struct device *parent,
         return dev;
 
 error:
-        kfree(dev);
+        put_device(dev);
         return ERR_PTR(retval);
 }
 EXPORT_SYMBOL_GPL(device_create_vargs);
@@ -1314,6 +1327,11 @@ EXPORT_SYMBOL_GPL(device_destroy);
  * device_rename - renames a device
  * @dev: the pointer to the struct device to be renamed
  * @new_name: the new name of the device
+ *
+ * It is the responsibility of the caller to provide mutual
+ * exclusion between two different calls of device_rename
+ * on the same device to ensure that new_name is valid and
+ * won't conflict with other devices.
  */
 int device_rename(struct device *dev, char *new_name)
 {
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 3ac443b2ac08..20febc00a525 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -257,6 +257,9 @@ static int __driver_attach(struct device *dev, void *data)
          * is an error.
          */
 
+        if (drv->bus->match && !drv->bus->match(dev, drv))
+                return 0;
+
         if (dev->parent)        /* Needed for USB */
                 down(&dev->parent->sem);
         down(&dev->sem);
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 66b710c28812..dfcbfe504867 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -394,6 +394,53 @@ error:
 }
 EXPORT_SYMBOL_GPL(platform_device_register_simple);
 
+/**
+ * platform_device_register_data
+ * @parent: parent device for the device we're adding
+ * @name: base name of the device we're adding
+ * @id: instance id
+ * @data: platform specific data for this platform device
+ * @size: size of platform specific data
+ *
+ * This function creates a simple platform device that requires minimal
+ * resource and memory management. Canned release function freeing memory
+ * allocated for the device allows drivers using such devices to be
+ * unloaded without waiting for the last reference to the device to be
+ * dropped.
+ */
+struct platform_device *platform_device_register_data(
+                struct device *parent,
+                const char *name, int id,
+                const void *data, size_t size)
+{
+        struct platform_device *pdev;
+        int retval;
+
+        pdev = platform_device_alloc(name, id);
+        if (!pdev) {
+                retval = -ENOMEM;
+                goto error;
+        }
+
+        pdev->dev.parent = parent;
+
+        if (size) {
+                retval = platform_device_add_data(pdev, data, size);
+                if (retval)
+                        goto error;
+        }
+
+        retval = platform_device_add(pdev);
+        if (retval)
+                goto error;
+
+        return pdev;
+
+error:
+        platform_device_put(pdev);
+        return ERR_PTR(retval);
+}
+
 static int platform_drv_probe(struct device *_dev)
 {
         struct platform_driver *drv = to_platform_driver(_dev->driver);
@@ -865,7 +912,7 @@ static int platform_pm_restore_noirq(struct device *dev)
 
 #endif /* !CONFIG_HIBERNATION */
 
-struct pm_ext_ops platform_pm_ops = {
+static struct pm_ext_ops platform_pm_ops = {
         .base = {
                 .prepare = platform_pm_prepare,
                 .complete = platform_pm_complete,
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 03bde7524bc3..692c20ba5144 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -83,7 +83,7 @@ void device_pm_add(struct device *dev)
                  * transition is in progress in order to avoid leaving them
                  * unhandled down the road
                  */
-                WARN_ON(true);
+                dev_WARN(dev, "Parentless device registered during a PM transaction\n");
         }
 
         list_add_tail(&dev->power.entry, &dpm_list);