Driver core: "platform_driver_probe() can save codespace": save codespace
[powerpc.git] / drivers / base / core.c
index 68ad11a..67b79a7 100644 (file)
@@ -17,6 +17,7 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/kdev_t.h>
+#include <linux/notifier.h>
 
 #include <asm/semaphore.h>
 
@@ -153,20 +154,24 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
                               "MINOR=%u", MINOR(dev->devt));
        }
 
+#ifdef CONFIG_SYSFS_DEPRECATED
        /* add bus name (same as SUBSYSTEM, deprecated) */
        if (dev->bus)
                add_uevent_var(envp, num_envp, &i,
                               buffer, buffer_size, &length,
                               "PHYSDEVBUS=%s", dev->bus->name);
+#endif
 
        /* add driver name (PHYSDEV* values are deprecated)*/
        if (dev->driver) {
                add_uevent_var(envp, num_envp, &i,
                               buffer, buffer_size, &length,
                               "DRIVER=%s", dev->driver->name);
+#ifdef CONFIG_SYSFS_DEPRECATED
                add_uevent_var(envp, num_envp, &i,
                               buffer, buffer_size, &length,
                               "PHYSDEVDRIVER=%s", dev->driver->name);
+#endif
        }
 
        /* terminate, set to next free slot, shrink available space */
@@ -381,8 +386,55 @@ void device_initialize(struct device *dev)
        INIT_LIST_HEAD(&dev->node);
        init_MUTEX(&dev->sem);
        device_init_wakeup(dev, 0);
+       set_dev_node(dev, -1);
 }
 
+#ifdef CONFIG_SYSFS_DEPRECATED
+static int setup_parent(struct device *dev, struct device *parent)
+{
+       /* Set the parent to the class, not the parent device */
+       /* this keeps sysfs from having a symlink to make old udevs happy */
+       if (dev->class)
+               dev->kobj.parent = &dev->class->subsys.kset.kobj;
+       else if (parent)
+               dev->kobj.parent = &parent->kobj;
+
+       return 0;
+}
+#else
+static int virtual_device_parent(struct device *dev)
+{
+       if (!dev->class)
+               return -ENODEV;
+
+       if (!dev->class->virtual_dir) {
+               static struct kobject *virtual_dir = NULL;
+
+               if (!virtual_dir)
+                       virtual_dir = kobject_add_dir(&devices_subsys.kset.kobj, "virtual");
+               dev->class->virtual_dir = kobject_add_dir(virtual_dir, dev->class->name);
+       }
+
+       dev->kobj.parent = dev->class->virtual_dir;
+       return 0;
+}
+
+static int setup_parent(struct device *dev, struct device *parent)
+{
+       int error;
+
+       /* if this is a class device, and has no parent, create one */
+       if ((dev->class) && (parent == NULL)) {
+               error = virtual_device_parent(dev);
+               if (error)
+                       return error;
+       } else if (parent)
+               dev->kobj.parent = &parent->kobj;
+
+       return 0;
+}
+#endif
+
 /**
  *     device_add - add device to device hierarchy.
  *     @dev:   device.
@@ -405,29 +457,29 @@ int device_add(struct device *dev)
        if (!dev || !strlen(dev->bus_id))
                goto Error;
 
-       /* if this is a class device, and has no parent, create one */
-       if ((dev->class) && (dev->parent == NULL)) {
-               error = virtual_device_parent(dev);
-               if (error)
-                       goto Error;
-       }
+       pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id);
 
        parent = get_device(dev->parent);
 
-       pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id);
+       error = setup_parent(dev, parent);
+       if (error)
+               goto Error;
 
        /* first, register with generic layer. */
        kobject_set_name(&dev->kobj, "%s", dev->bus_id);
-       if (parent)
-               dev->kobj.parent = &parent->kobj;
-
-       if ((error = kobject_add(&dev->kobj)))
+       error = kobject_add(&dev->kobj);
+       if (error)
                goto Error;
 
        /* notify platform of device entry */
        if (platform_notify)
                platform_notify(dev);
 
+       /* notify clients of device entry (new way) */
+       if (dev->bus)
+               blocking_notifier_call_chain(&dev->bus->bus_notifier,
+                                            BUS_NOTIFY_ADD_DEVICE, dev);
+
        dev->uevent_attr.attr.name = "uevent";
        dev->uevent_attr.attr.mode = S_IWUSR;
        if (dev->driver)
@@ -461,13 +513,18 @@ int device_add(struct device *dev)
        if (dev->class) {
                sysfs_create_link(&dev->kobj, &dev->class->subsys.kset.kobj,
                                  "subsystem");
-               sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj,
-                                 dev->bus_id);
+               /* If this is not a "fake" compatible device, then create the
+                * symlink from the class to the device. */
+               if (dev->kobj.parent != &dev->class->subsys.kset.kobj)
+                       sysfs_create_link(&dev->class->subsys.kset.kobj,
+                                         &dev->kobj, dev->bus_id);
+#ifdef CONFIG_SYSFS_DEPRECATED
                if (parent) {
                        sysfs_create_link(&dev->kobj, &dev->parent->kobj, "device");
                        class_name = make_class_name(dev->class->name, &dev->kobj);
                        sysfs_create_link(&dev->parent->kobj, &dev->kobj, class_name);
                }
+#endif
        }
 
        if ((error = device_add_attrs(dev)))
@@ -504,6 +561,9 @@ int device_add(struct device *dev)
  BusError:
        device_pm_remove(dev);
  PMError:
+       if (dev->bus)
+               blocking_notifier_call_chain(&dev->bus->bus_notifier,
+                                            BUS_NOTIFY_DEL_DEVICE, dev);
        device_remove_groups(dev);
  GroupError:
        device_remove_attrs(dev);
@@ -586,22 +646,31 @@ void put_device(struct device * dev)
 void device_del(struct device * dev)
 {
        struct device * parent = dev->parent;
-       char *class_name = NULL;
        struct class_interface *class_intf;
 
        if (parent)
                klist_del(&dev->knode_parent);
-       if (dev->devt_attr)
+       if (dev->devt_attr) {
                device_remove_file(dev, dev->devt_attr);
+               kfree(dev->devt_attr);
+       }
        if (dev->class) {
                sysfs_remove_link(&dev->kobj, "subsystem");
-               sysfs_remove_link(&dev->class->subsys.kset.kobj, dev->bus_id);
-               class_name = make_class_name(dev->class->name, &dev->kobj);
+               /* If this is not a "fake" compatible device, remove the
+                * symlink from the class to the device. */
+               if (dev->kobj.parent != &dev->class->subsys.kset.kobj)
+                       sysfs_remove_link(&dev->class->subsys.kset.kobj,
+                                         dev->bus_id);
+#ifdef CONFIG_SYSFS_DEPRECATED
                if (parent) {
-                       sysfs_remove_link(&dev->kobj, "device");
+                       char *class_name = make_class_name(dev->class->name,
+                                                          &dev->kobj);
                        sysfs_remove_link(&dev->parent->kobj, class_name);
+                       kfree(class_name);
+                       sysfs_remove_link(&dev->kobj, "device");
                }
-               kfree(class_name);
+#endif
+
                down(&dev->class->sem);
                /* notify any interfaces that the device is now gone */
                list_for_each_entry(class_intf, &dev->class->interfaces, node)
@@ -614,13 +683,16 @@ void device_del(struct device * dev)
        device_remove_file(dev, &dev->uevent_attr);
        device_remove_groups(dev);
        device_remove_attrs(dev);
+       bus_remove_device(dev);
 
        /* Notify the platform of the removal, in case they
         * need to do anything...
         */
        if (platform_notify_remove)
                platform_notify_remove(dev);
-       bus_remove_device(dev);
+       if (dev->bus)
+               blocking_notifier_call_chain(&dev->bus->bus_notifier,
+                                            BUS_NOTIFY_DEL_DEVICE, dev);
        device_pm_remove(dev);
        kobject_uevent(&dev->kobj, KOBJ_REMOVE);
        kobject_del(&dev->kobj);
@@ -679,12 +751,45 @@ int device_for_each_child(struct device * parent, void * data,
        return error;
 }
 
+/**
+ * device_find_child - device iterator for locating a particular device.
+ * @parent: parent struct device
+ * @data: Data to pass to match function
+ * @match: Callback function to check device
+ *
+ * This is similar to the device_for_each_child() function above, but it
+ * returns a reference to a device that is 'found' for later use, as
+ * determined by the @match callback.
+ *
+ * The callback should return 0 if the device doesn't match and non-zero
+ * if it does.  If the callback returns non-zero and a reference to the
+ * current device can be obtained, this function will return to the caller
+ * and not iterate over any more devices.
+ */
+struct device * device_find_child(struct device *parent, void *data,
+                                 int (*match)(struct device *, void *))
+{
+       struct klist_iter i;
+       struct device *child;
+
+       if (!parent)
+               return NULL;
+
+       klist_iter_init(&parent->klist_children, &i);
+       while ((child = next_device(&i)))
+               if (match(child, data) && get_device(child))
+                       break;
+       klist_iter_exit(&i);
+       return child;
+}
+
 int __init devices_init(void)
 {
        return subsystem_register(&devices_subsys);
 }
 
 EXPORT_SYMBOL_GPL(device_for_each_child);
+EXPORT_SYMBOL_GPL(device_find_child);
 
 EXPORT_SYMBOL_GPL(device_initialize);
 EXPORT_SYMBOL_GPL(device_add);
@@ -807,8 +912,10 @@ int device_rename(struct device *dev, char *new_name)
 
        pr_debug("DEVICE: renaming '%s' to '%s'\n", dev->bus_id, new_name);
 
+#ifdef CONFIG_SYSFS_DEPRECATED
        if ((dev->class) && (dev->parent))
                old_class_name = make_class_name(dev->class->name, &dev->kobj);
+#endif
 
        if (dev->class) {
                old_symlink_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
@@ -823,6 +930,7 @@ int device_rename(struct device *dev, char *new_name)
 
        error = kobject_rename(&dev->kobj, new_name);
 
+#ifdef CONFIG_SYSFS_DEPRECATED
        if (old_class_name) {
                new_class_name = make_class_name(dev->class->name, &dev->kobj);
                if (new_class_name) {
@@ -831,6 +939,8 @@ int device_rename(struct device *dev, char *new_name)
                        sysfs_remove_link(&dev->parent->kobj, old_class_name);
                }
        }
+#endif
+
        if (dev->class) {
                sysfs_remove_link(&dev->class->subsys.kset.kobj,
                                  old_symlink_name);
@@ -846,3 +956,95 @@ int device_rename(struct device *dev, char *new_name)
 
        return error;
 }
+
+
+static int device_move_class_links(struct device *dev,
+                                  struct device *old_parent,
+                                  struct device *new_parent)
+{
+#ifdef CONFIG_SYSFS_DEPRECATED
+       int error;
+       char *class_name;
+
+       class_name = make_class_name(dev->class->name, &dev->kobj);
+       if (!class_name) {
+               error = PTR_ERR(class_name);
+               class_name = NULL;
+               goto out;
+       }
+       if (old_parent) {
+               sysfs_remove_link(&dev->kobj, "device");
+               sysfs_remove_link(&old_parent->kobj, class_name);
+       }
+       error = sysfs_create_link(&dev->kobj, &new_parent->kobj, "device");
+       if (error)
+               goto out;
+       error = sysfs_create_link(&new_parent->kobj, &dev->kobj, class_name);
+       if (error)
+               sysfs_remove_link(&dev->kobj, "device");
+out:
+       kfree(class_name);
+       return error;
+#else
+       return 0;
+#endif
+}
+
+/**
+ * device_move - moves a device to a new parent
+ * @dev: the pointer to the struct device to be moved
+ * @new_parent: the new parent of the device
+ */
+int device_move(struct device *dev, struct device *new_parent)
+{
+       int error;
+       struct device *old_parent;
+
+       dev = get_device(dev);
+       if (!dev)
+               return -EINVAL;
+
+       if (!device_is_registered(dev)) {
+               error = -EINVAL;
+               goto out;
+       }
+       new_parent = get_device(new_parent);
+       if (!new_parent) {
+               error = -EINVAL;
+               goto out;
+       }
+       pr_debug("DEVICE: moving '%s' to '%s'\n", dev->bus_id,
+               new_parent->bus_id);
+       error = kobject_move(&dev->kobj, &new_parent->kobj);
+       if (error) {
+               put_device(new_parent);
+               goto out;
+       }
+       old_parent = dev->parent;
+       dev->parent = new_parent;
+       if (old_parent)
+               klist_remove(&dev->knode_parent);
+       klist_add_tail(&dev->knode_parent, &new_parent->klist_children);
+       if (!dev->class)
+               goto out_put;
+       error = device_move_class_links(dev, old_parent, new_parent);
+       if (error) {
+               /* We ignore errors on cleanup since we're hosed anyway... */
+               device_move_class_links(dev, new_parent, old_parent);
+               if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
+                       klist_remove(&dev->knode_parent);
+                       if (old_parent)
+                               klist_add_tail(&dev->knode_parent,
+                                              &old_parent->klist_children);
+               }
+               put_device(new_parent);
+               goto out;
+       }
+out_put:
+       put_device(old_parent);
+out:
+       put_device(dev);
+       return error;
+}
+
+EXPORT_SYMBOL_GPL(device_move);