firewire: fw-sbp2: use an own workqueue (fix system responsiveness)
[safe/jmp/linux-2.6] / drivers / base / core.c
index d5e15a0..c134341 100644 (file)
@@ -3,18 +3,21 @@
  *
  * Copyright (c) 2002-3 Patrick Mochel
  * Copyright (c) 2002-3 Open Source Development Labs
+ * Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de>
+ * Copyright (c) 2006 Novell, Inc.
  *
  * This file is released under the GPLv2
  *
  */
 
-#include <linux/config.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/kdev_t.h>
+#include <linux/notifier.h>
 
 #include <asm/semaphore.h>
 
@@ -28,6 +31,23 @@ int (*platform_notify_remove)(struct device * dev) = NULL;
  * sysfs bindings for devices.
  */
 
+/**
+ * dev_driver_string - Return a device's driver name, if at all possible
+ * @dev: struct device to get the name of
+ *
+ * Will return the device's driver's name if it is bound to a device.  If
+ * the device is not bound to a device, it will return the name of the bus
+ * it is attached to.  If it is not attached to a bus either, an empty
+ * string will be returned.
+ */
+const char *dev_driver_string(struct device *dev)
+{
+       return dev->driver ? dev->driver->name :
+                       (dev->bus ? dev->bus->name :
+                       (dev->class ? dev->class->name : ""));
+}
+EXPORT_SYMBOL(dev_driver_string);
+
 #define to_dev(obj) container_of(obj, struct device, kobj)
 #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
 
@@ -76,6 +96,10 @@ static void device_release(struct kobject * kobj)
 
        if (dev->release)
                dev->release(dev);
+       else if (dev->type && dev->type->release)
+               dev->type->release(dev);
+       else if (dev->class && dev->class->dev_release)
+               dev->class->dev_release(dev);
        else {
                printk(KERN_ERR "Device '%s' does not have a release() function, "
                        "it is broken and must be fixed.\n",
@@ -84,7 +108,7 @@ static void device_release(struct kobject * kobj)
        }
 }
 
-static struct kobj_type ktype_device = {
+static struct kobj_type device_ktype = {
        .release        = device_release,
        .sysfs_ops      = &dev_sysfs_ops,
 };
@@ -94,10 +118,14 @@ static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
 {
        struct kobj_type *ktype = get_ktype(kobj);
 
-       if (ktype == &ktype_device) {
+       if (ktype == &device_ktype) {
                struct device *dev = to_dev(kobj);
+               if (dev->uevent_suppress)
+                       return 0;
                if (dev->bus)
                        return 1;
+               if (dev->class)
+                       return 1;
        }
        return 0;
 }
@@ -106,43 +134,83 @@ static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
 {
        struct device *dev = to_dev(kobj);
 
-       return dev->bus->name;
+       if (dev->bus)
+               return dev->bus->name;
+       if (dev->class)
+               return dev->class->name;
+       return NULL;
 }
 
-static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
-                       int num_envp, char *buffer, int buffer_size)
+static int dev_uevent(struct kset *kset, struct kobject *kobj,
+                     struct kobj_uevent_env *env)
 {
        struct device *dev = to_dev(kobj);
-       int i = 0;
-       int length = 0;
        int retval = 0;
 
-       /* add bus name of physical device */
-       if (dev->bus)
-               add_uevent_var(envp, num_envp, &i,
-                              buffer, buffer_size, &length,
-                              "PHYSDEVBUS=%s", dev->bus->name);
+       /* add the major/minor if present */
+       if (MAJOR(dev->devt)) {
+               add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt));
+               add_uevent_var(env, "MINOR=%u", MINOR(dev->devt));
+       }
+
+       if (dev->type && dev->type->name)
+               add_uevent_var(env, "DEVTYPE=%s", dev->type->name);
 
-       /* add driver name of physical device */
        if (dev->driver)
-               add_uevent_var(envp, num_envp, &i,
-                              buffer, buffer_size, &length,
-                              "PHYSDEVDRIVER=%s", dev->driver->name);
+               add_uevent_var(env, "DRIVER=%s", dev->driver->name);
+
+#ifdef CONFIG_SYSFS_DEPRECATED
+       if (dev->class) {
+               struct device *parent = dev->parent;
+
+               /* find first bus device in parent chain */
+               while (parent && !parent->bus)
+                       parent = parent->parent;
+               if (parent && parent->bus) {
+                       const char *path;
+
+                       path = kobject_get_path(&parent->kobj, GFP_KERNEL);
+                       if (path) {
+                               add_uevent_var(env, "PHYSDEVPATH=%s", path);
+                               kfree(path);
+                       }
+
+                       add_uevent_var(env, "PHYSDEVBUS=%s", parent->bus->name);
+
+                       if (parent->driver)
+                               add_uevent_var(env, "PHYSDEVDRIVER=%s",
+                                              parent->driver->name);
+               }
+       } else if (dev->bus) {
+               add_uevent_var(env, "PHYSDEVBUS=%s", dev->bus->name);
 
-       /* terminate, set to next free slot, shrink available space */
-       envp[i] = NULL;
-       envp = &envp[i];
-       num_envp -= i;
-       buffer = &buffer[length];
-       buffer_size -= length;
+               if (dev->driver)
+                       add_uevent_var(env, "PHYSDEVDRIVER=%s", dev->driver->name);
+       }
+#endif
 
+       /* have the bus specific function add its stuff */
        if (dev->bus && dev->bus->uevent) {
-               /* have the bus specific function add its stuff */
-               retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size);
-                       if (retval) {
-                       pr_debug ("%s - uevent() returned %d\n",
+               retval = dev->bus->uevent(dev, env);
+               if (retval)
+                       pr_debug ("%s: bus uevent() returned %d\n",
                                  __FUNCTION__, retval);
-               }
+       }
+
+       /* have the class specific function add its stuff */
+       if (dev->class && dev->class->dev_uevent) {
+               retval = dev->class->dev_uevent(dev, env);
+               if (retval)
+                       pr_debug("%s: class uevent() returned %d\n",
+                                __FUNCTION__, retval);
+       }
+
+       /* have the device type specific fuction add its stuff */
+       if (dev->type && dev->type->uevent) {
+               retval = dev->type->uevent(dev, env);
+               if (retval)
+                       pr_debug("%s: dev_type uevent() returned %d\n",
+                                __FUNCTION__, retval);
        }
 
        return retval;
@@ -154,18 +222,190 @@ static struct kset_uevent_ops device_uevent_ops = {
        .uevent =       dev_uevent,
 };
 
+static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
+                          char *buf)
+{
+       struct kobject *top_kobj;
+       struct kset *kset;
+       struct kobj_uevent_env *env = NULL;
+       int i;
+       size_t count = 0;
+       int retval;
+
+       /* search the kset, the device belongs to */
+       top_kobj = &dev->kobj;
+       while (!top_kobj->kset && top_kobj->parent)
+               top_kobj = top_kobj->parent;
+       if (!top_kobj->kset)
+               goto out;
+
+       kset = top_kobj->kset;
+       if (!kset->uevent_ops || !kset->uevent_ops->uevent)
+               goto out;
+
+       /* respect filter */
+       if (kset->uevent_ops && kset->uevent_ops->filter)
+               if (!kset->uevent_ops->filter(kset, &dev->kobj))
+                       goto out;
+
+       env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
+       if (!env)
+               return -ENOMEM;
+
+       /* let the kset specific function add its keys */
+       retval = kset->uevent_ops->uevent(kset, &dev->kobj, env);
+       if (retval)
+               goto out;
+
+       /* copy keys to file */
+       for (i = 0; i < env->envp_idx; i++)
+               count += sprintf(&buf[count], "%s\n", env->envp[i]);
+out:
+       kfree(env);
+       return count;
+}
+
 static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
                            const char *buf, size_t count)
 {
+       enum kobject_action action;
+
+       if (kobject_action_type(buf, count, &action) == 0) {
+               kobject_uevent(&dev->kobj, action);
+               goto out;
+       }
+
+       dev_err(dev, "uevent: unsupported action-string; this will "
+                    "be ignored in a future kernel version\n");
        kobject_uevent(&dev->kobj, KOBJ_ADD);
+out:
        return count;
 }
 
+static struct device_attribute uevent_attr =
+       __ATTR(uevent, S_IRUGO | S_IWUSR, show_uevent, store_uevent);
+
+static int device_add_attributes(struct device *dev,
+                                struct device_attribute *attrs)
+{
+       int error = 0;
+       int i;
+
+       if (attrs) {
+               for (i = 0; attr_name(attrs[i]); i++) {
+                       error = device_create_file(dev, &attrs[i]);
+                       if (error)
+                               break;
+               }
+               if (error)
+                       while (--i >= 0)
+                               device_remove_file(dev, &attrs[i]);
+       }
+       return error;
+}
+
+static void device_remove_attributes(struct device *dev,
+                                    struct device_attribute *attrs)
+{
+       int i;
+
+       if (attrs)
+               for (i = 0; attr_name(attrs[i]); i++)
+                       device_remove_file(dev, &attrs[i]);
+}
+
+static int device_add_groups(struct device *dev,
+                            struct attribute_group **groups)
+{
+       int error = 0;
+       int i;
+
+       if (groups) {
+               for (i = 0; groups[i]; i++) {
+                       error = sysfs_create_group(&dev->kobj, groups[i]);
+                       if (error) {
+                               while (--i >= 0)
+                                       sysfs_remove_group(&dev->kobj, groups[i]);
+                               break;
+                       }
+               }
+       }
+       return error;
+}
+
+static void device_remove_groups(struct device *dev,
+                                struct attribute_group **groups)
+{
+       int i;
+
+       if (groups)
+               for (i = 0; groups[i]; i++)
+                       sysfs_remove_group(&dev->kobj, groups[i]);
+}
+
+static int device_add_attrs(struct device *dev)
+{
+       struct class *class = dev->class;
+       struct device_type *type = dev->type;
+       int error;
+
+       if (class) {
+               error = device_add_attributes(dev, class->dev_attrs);
+               if (error)
+                       return error;
+       }
+
+       if (type) {
+               error = device_add_groups(dev, type->groups);
+               if (error)
+                       goto err_remove_class_attrs;
+       }
+
+       error = device_add_groups(dev, dev->groups);
+       if (error)
+               goto err_remove_type_groups;
+
+       return 0;
+
+ err_remove_type_groups:
+       if (type)
+               device_remove_groups(dev, type->groups);
+ err_remove_class_attrs:
+       if (class)
+               device_remove_attributes(dev, class->dev_attrs);
+
+       return error;
+}
+
+static void device_remove_attrs(struct device *dev)
+{
+       struct class *class = dev->class;
+       struct device_type *type = dev->type;
+
+       device_remove_groups(dev, dev->groups);
+
+       if (type)
+               device_remove_groups(dev, type->groups);
+
+       if (class)
+               device_remove_attributes(dev, class->dev_attrs);
+}
+
+
+static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
+                       char *buf)
+{
+       return print_dev_t(buf, dev->devt);
+}
+
+static struct device_attribute devt_attr =
+       __ATTR(dev, S_IRUGO, show_dev, NULL);
+
 /*
  *     devices_subsys - structure to be registered with kobject core.
  */
 
-decl_subsys(devices, &ktype_device, &device_uevent_ops);
+decl_subsys(devices, &device_ktype, &device_uevent_ops);
 
 
 /**
@@ -198,6 +438,65 @@ void device_remove_file(struct device * dev, struct device_attribute * attr)
        }
 }
 
+/**
+ * device_create_bin_file - create sysfs binary attribute file for device.
+ * @dev: device.
+ * @attr: device binary attribute descriptor.
+ */
+int device_create_bin_file(struct device *dev, struct bin_attribute *attr)
+{
+       int error = -EINVAL;
+       if (dev)
+               error = sysfs_create_bin_file(&dev->kobj, attr);
+       return error;
+}
+EXPORT_SYMBOL_GPL(device_create_bin_file);
+
+/**
+ * device_remove_bin_file - remove sysfs binary attribute file
+ * @dev: device.
+ * @attr: device binary attribute descriptor.
+ */
+void device_remove_bin_file(struct device *dev, struct bin_attribute *attr)
+{
+       if (dev)
+               sysfs_remove_bin_file(&dev->kobj, attr);
+}
+EXPORT_SYMBOL_GPL(device_remove_bin_file);
+
+/**
+ * device_schedule_callback_owner - helper to schedule a callback for a device
+ * @dev: device.
+ * @func: callback function to invoke later.
+ * @owner: module owning the callback routine
+ *
+ * Attribute methods must not unregister themselves or their parent device
+ * (which would amount to the same thing).  Attempts to do so will deadlock,
+ * since unregistration is mutually exclusive with driver callbacks.
+ *
+ * Instead methods can call this routine, which will attempt to allocate
+ * and schedule a workqueue request to call back @func with @dev as its
+ * argument in the workqueue's process context.  @dev will be pinned until
+ * @func returns.
+ *
+ * This routine is usually called via the inline device_schedule_callback(),
+ * which automatically sets @owner to THIS_MODULE.
+ *
+ * Returns 0 if the request was submitted, -ENOMEM if storage could not
+ * be allocated, -ENODEV if a reference to @owner isn't available.
+ *
+ * NOTE: This routine won't work if CONFIG_SYSFS isn't set!  It uses an
+ * underlying sysfs routine (since it is intended for use by attribute
+ * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
+ */
+int device_schedule_callback_owner(struct device *dev,
+               void (*func)(struct device *), struct module *owner)
+{
+       return sysfs_schedule_callback(&dev->kobj,
+                       (void (*)(void *)) func, dev, owner);
+}
+EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
+
 static void klist_children_get(struct klist_node *n)
 {
        struct device *dev = container_of(n, struct device, knode_parent);
@@ -231,8 +530,185 @@ void device_initialize(struct device *dev)
        klist_init(&dev->klist_children, klist_children_get,
                   klist_children_put);
        INIT_LIST_HEAD(&dev->dma_pools);
+       INIT_LIST_HEAD(&dev->node);
        init_MUTEX(&dev->sem);
+       spin_lock_init(&dev->devres_lock);
+       INIT_LIST_HEAD(&dev->devres_head);
        device_init_wakeup(dev, 0);
+       set_dev_node(dev, -1);
+}
+
+#ifdef CONFIG_SYSFS_DEPRECATED
+static struct kobject * get_device_parent(struct device *dev,
+                                         struct device *parent)
+{
+       /*
+        * Set the parent to the class, not the parent device
+        * for topmost devices in class hierarchy.
+        * This keeps sysfs from having a symlink to make old
+        * udevs happy
+        */
+       if (dev->class && (!parent || parent->class != dev->class))
+               return &dev->class->subsys.kobj;
+       else if (parent)
+               return &parent->kobj;
+
+       return NULL;
+}
+#else
+static struct kobject *virtual_device_parent(struct device *dev)
+{
+       static struct kobject *virtual_dir = NULL;
+
+       if (!virtual_dir)
+               virtual_dir = kobject_add_dir(&devices_subsys.kobj, "virtual");
+
+       return virtual_dir;
+}
+
+static struct kobject * get_device_parent(struct device *dev,
+                                         struct device *parent)
+{
+       if (dev->class) {
+               struct kobject *kobj = NULL;
+               struct kobject *parent_kobj;
+               struct kobject *k;
+
+               /*
+                * If we have no parent, we live in "virtual".
+                * Class-devices with a bus-device as parent, live
+                * in a class-directory to prevent namespace collisions.
+                */
+               if (parent == NULL)
+                       parent_kobj = virtual_device_parent(dev);
+               else if (parent->class)
+                       return &parent->kobj;
+               else
+                       parent_kobj = &parent->kobj;
+
+               /* find our class-directory at the parent and reference it */
+               spin_lock(&dev->class->class_dirs.list_lock);
+               list_for_each_entry(k, &dev->class->class_dirs.list, entry)
+                       if (k->parent == parent_kobj) {
+                               kobj = kobject_get(k);
+                               break;
+                       }
+               spin_unlock(&dev->class->class_dirs.list_lock);
+               if (kobj)
+                       return kobj;
+
+               /* or create a new class-directory at the parent device */
+               return kobject_kset_add_dir(&dev->class->class_dirs,
+                                           parent_kobj, dev->class->name);
+       }
+
+       if (parent)
+               return &parent->kobj;
+       return NULL;
+}
+#endif
+
+static int setup_parent(struct device *dev, struct device *parent)
+{
+       struct kobject *kobj;
+       kobj = get_device_parent(dev, parent);
+       if (IS_ERR(kobj))
+               return PTR_ERR(kobj);
+       if (kobj)
+               dev->kobj.parent = kobj;
+       return 0;
+}
+
+static int device_add_class_symlinks(struct device *dev)
+{
+       int error;
+
+       if (!dev->class)
+               return 0;
+       error = sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj,
+                                 "subsystem");
+       if (error)
+               goto out;
+       /*
+        * 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.kobj) {
+               error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
+                                         dev->bus_id);
+               if (error)
+                       goto out_subsys;
+       }
+       if (dev->parent) {
+#ifdef CONFIG_SYSFS_DEPRECATED
+               {
+                       struct device *parent = dev->parent;
+                       char *class_name;
+
+                       /*
+                        * In old sysfs stacked class devices had 'device'
+                        * link pointing to real device instead of parent
+                        */
+                       while (parent->class && !parent->bus && parent->parent)
+                               parent = parent->parent;
+
+                       error = sysfs_create_link(&dev->kobj,
+                                                 &parent->kobj,
+                                                 "device");
+                       if (error)
+                               goto out_busid;
+
+                       class_name = make_class_name(dev->class->name,
+                                                       &dev->kobj);
+                       if (class_name)
+                               error = sysfs_create_link(&dev->parent->kobj,
+                                                       &dev->kobj, class_name);
+                       kfree(class_name);
+                       if (error)
+                               goto out_device;
+               }
+#else
+               error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
+                                         "device");
+               if (error)
+                       goto out_busid;
+#endif
+       }
+       return 0;
+
+#ifdef CONFIG_SYSFS_DEPRECATED
+out_device:
+       if (dev->parent)
+               sysfs_remove_link(&dev->kobj, "device");
+#endif
+out_busid:
+       if (dev->kobj.parent != &dev->class->subsys.kobj)
+               sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
+out_subsys:
+       sysfs_remove_link(&dev->kobj, "subsystem");
+out:
+       return error;
+}
+
+static void device_remove_class_symlinks(struct device *dev)
+{
+       if (!dev->class)
+               return;
+       if (dev->parent) {
+#ifdef CONFIG_SYSFS_DEPRECATED
+               char *class_name;
+
+               class_name = make_class_name(dev->class->name, &dev->kobj);
+               if (class_name) {
+                       sysfs_remove_link(&dev->parent->kobj, class_name);
+                       kfree(class_name);
+               }
+#endif
+               sysfs_remove_link(&dev->kobj, "device");
+       }
+       if (dev->kobj.parent != &dev->class->subsys.kobj)
+               sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
+       sysfs_remove_link(&dev->kobj, "subsystem");
 }
 
 /**
@@ -249,49 +725,111 @@ void device_initialize(struct device *dev)
 int device_add(struct device *dev)
 {
        struct device *parent = NULL;
+       struct class_interface *class_intf;
        int error = -EINVAL;
 
        dev = get_device(dev);
        if (!dev || !strlen(dev->bus_id))
                goto Error;
 
-       parent = get_device(dev->parent);
-
        pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id);
 
+       parent = get_device(dev->parent);
+       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;
 
-       dev->uevent_attr.attr.name = "uevent";
-       dev->uevent_attr.attr.mode = S_IWUSR;
-       if (dev->driver)
-               dev->uevent_attr.attr.owner = dev->driver->owner;
-       dev->uevent_attr.store = store_uevent;
-       device_create_file(dev, &dev->uevent_attr);
+       /* 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);
 
-       if ((error = device_pm_add(dev)))
+       error = device_create_file(dev, &uevent_attr);
+       if (error)
+               goto attrError;
+
+       if (MAJOR(dev->devt)) {
+               error = device_create_file(dev, &devt_attr);
+               if (error)
+                       goto ueventattrError;
+       }
+
+       error = device_add_class_symlinks(dev);
+       if (error)
+               goto SymlinkError;
+       error = device_add_attrs(dev);
+       if (error)
+               goto AttrsError;
+       error = device_pm_add(dev);
+       if (error)
                goto PMError;
-       if ((error = bus_add_device(dev)))
+       error = bus_add_device(dev);
+       if (error)
                goto BusError;
        kobject_uevent(&dev->kobj, KOBJ_ADD);
        bus_attach_device(dev);
        if (parent)
                klist_add_tail(&dev->knode_parent, &parent->klist_children);
 
-       /* notify platform of device entry */
-       if (platform_notify)
-               platform_notify(dev);
+       if (dev->class) {
+               down(&dev->class->sem);
+               /* tie the class to the device */
+               list_add_tail(&dev->node, &dev->class->devices);
+
+               /* notify any interfaces that the device is here */
+               list_for_each_entry(class_intf, &dev->class->interfaces, node)
+                       if (class_intf->add_dev)
+                               class_intf->add_dev(dev, class_intf);
+               up(&dev->class->sem);
+       }
  Done:
        put_device(dev);
        return error;
  BusError:
        device_pm_remove(dev);
  PMError:
+       if (dev->bus)
+               blocking_notifier_call_chain(&dev->bus->bus_notifier,
+                                            BUS_NOTIFY_DEL_DEVICE, dev);
+       device_remove_attrs(dev);
+ AttrsError:
+       device_remove_class_symlinks(dev);
+ SymlinkError:
+       if (MAJOR(dev->devt))
+               device_remove_file(dev, &devt_attr);
+
+       if (dev->class) {
+               sysfs_remove_link(&dev->kobj, "subsystem");
+               /* If this is not a "fake" compatible device, remove the
+                * symlink from the class to the device. */
+               if (dev->kobj.parent != &dev->class->subsys.kobj)
+                       sysfs_remove_link(&dev->class->subsys.kobj,
+                                         dev->bus_id);
+               if (parent) {
+#ifdef CONFIG_SYSFS_DEPRECATED
+                       char *class_name = make_class_name(dev->class->name,
+                                                          &dev->kobj);
+                       if (class_name)
+                               sysfs_remove_link(&dev->parent->kobj,
+                                                 class_name);
+                       kfree(class_name);
+#endif
+                       sysfs_remove_link(&dev->kobj, "device");
+               }
+       }
+ ueventattrError:
+       device_remove_file(dev, &uevent_attr);
+ attrError:
        kobject_uevent(&dev->kobj, KOBJ_REMOVE);
        kobject_del(&dev->kobj);
  Error:
@@ -363,17 +901,84 @@ void put_device(struct device * dev)
 void device_del(struct device * dev)
 {
        struct device * parent = dev->parent;
+       struct class_interface *class_intf;
 
        if (parent)
                klist_del(&dev->knode_parent);
-       device_remove_file(dev, &dev->uevent_attr);
+       if (MAJOR(dev->devt))
+               device_remove_file(dev, &devt_attr);
+       if (dev->class) {
+               sysfs_remove_link(&dev->kobj, "subsystem");
+               /* If this is not a "fake" compatible device, remove the
+                * symlink from the class to the device. */
+               if (dev->kobj.parent != &dev->class->subsys.kobj)
+                       sysfs_remove_link(&dev->class->subsys.kobj,
+                                         dev->bus_id);
+               if (parent) {
+#ifdef CONFIG_SYSFS_DEPRECATED
+                       char *class_name = make_class_name(dev->class->name,
+                                                          &dev->kobj);
+                       if (class_name)
+                               sysfs_remove_link(&dev->parent->kobj,
+                                                 class_name);
+                       kfree(class_name);
+#endif
+                       sysfs_remove_link(&dev->kobj, "device");
+               }
+
+               down(&dev->class->sem);
+               /* notify any interfaces that the device is now gone */
+               list_for_each_entry(class_intf, &dev->class->interfaces, node)
+                       if (class_intf->remove_dev)
+                               class_intf->remove_dev(dev, class_intf);
+               /* remove the device from the class list */
+               list_del_init(&dev->node);
+               up(&dev->class->sem);
+
+               /* If we live in a parent class-directory, unreference it */
+               if (dev->kobj.parent->kset == &dev->class->class_dirs) {
+                       struct device *d;
+                       int other = 0;
+
+                       /*
+                        * if we are the last child of our class, delete
+                        * our class-directory at this parent
+                        */
+                       down(&dev->class->sem);
+                       list_for_each_entry(d, &dev->class->devices, node) {
+                               if (d == dev)
+                                       continue;
+                               if (d->kobj.parent == dev->kobj.parent) {
+                                       other = 1;
+                                       break;
+                               }
+                       }
+                       if (!other)
+                               kobject_del(dev->kobj.parent);
+
+                       kobject_put(dev->kobj.parent);
+                       up(&dev->class->sem);
+               }
+       }
+       device_remove_file(dev, &uevent_attr);
+       device_remove_attrs(dev);
+       bus_remove_device(dev);
+
+       /*
+        * Some platform devices are driven without driver attached
+        * and managed resources may have been acquired.  Make sure
+        * all resources are released.
+        */
+       devres_release_all(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);
@@ -432,12 +1037,45 @@ 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);
@@ -450,3 +1088,267 @@ EXPORT_SYMBOL_GPL(put_device);
 
 EXPORT_SYMBOL_GPL(device_create_file);
 EXPORT_SYMBOL_GPL(device_remove_file);
+
+
+static void device_create_release(struct device *dev)
+{
+       pr_debug("%s called for %s\n", __FUNCTION__, dev->bus_id);
+       kfree(dev);
+}
+
+/**
+ * device_create - creates a device and registers it with sysfs
+ * @class: pointer to the struct class that this device should be registered to
+ * @parent: pointer to the parent struct device of this new device, if any
+ * @devt: the dev_t for the char device to be added
+ * @fmt: string for the device's name
+ *
+ * This function can be used by char device classes.  A struct device
+ * will be created in sysfs, registered to the specified class.
+ *
+ * A "dev" file will be created, showing the dev_t for the device, if
+ * the dev_t is not 0,0.
+ * If a pointer to a parent struct device is passed in, the newly created
+ * struct device will be a child of that device in sysfs.
+ * The pointer to the struct device will be returned from the call.
+ * Any further sysfs files that might be required can be created using this
+ * pointer.
+ *
+ * Note: the struct class passed to this function must have previously
+ * been created with a call to class_create().
+ */
+struct device *device_create(struct class *class, struct device *parent,
+                            dev_t devt, const char *fmt, ...)
+{
+       va_list args;
+       struct device *dev = NULL;
+       int retval = -ENODEV;
+
+       if (class == NULL || IS_ERR(class))
+               goto error;
+
+       dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+       if (!dev) {
+               retval = -ENOMEM;
+               goto error;
+       }
+
+       dev->devt = devt;
+       dev->class = class;
+       dev->parent = parent;
+       dev->release = device_create_release;
+
+       va_start(args, fmt);
+       vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
+       va_end(args);
+       retval = device_register(dev);
+       if (retval)
+               goto error;
+
+       return dev;
+
+error:
+       kfree(dev);
+       return ERR_PTR(retval);
+}
+EXPORT_SYMBOL_GPL(device_create);
+
+/**
+ * device_destroy - removes a device that was created with device_create()
+ * @class: pointer to the struct class that this device was registered with
+ * @devt: the dev_t of the device that was previously registered
+ *
+ * This call unregisters and cleans up a device that was created with a
+ * call to device_create().
+ */
+void device_destroy(struct class *class, dev_t devt)
+{
+       struct device *dev = NULL;
+       struct device *dev_tmp;
+
+       down(&class->sem);
+       list_for_each_entry(dev_tmp, &class->devices, node) {
+               if (dev_tmp->devt == devt) {
+                       dev = dev_tmp;
+                       break;
+               }
+       }
+       up(&class->sem);
+
+       if (dev)
+               device_unregister(dev);
+}
+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
+ */
+int device_rename(struct device *dev, char *new_name)
+{
+       char *old_class_name = NULL;
+       char *new_class_name = NULL;
+       char *old_device_name = NULL;
+       int error;
+
+       dev = get_device(dev);
+       if (!dev)
+               return -EINVAL;
+
+       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
+
+       old_device_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
+       if (!old_device_name) {
+               error = -ENOMEM;
+               goto out;
+       }
+       strlcpy(old_device_name, dev->bus_id, BUS_ID_SIZE);
+       strlcpy(dev->bus_id, new_name, BUS_ID_SIZE);
+
+       error = kobject_rename(&dev->kobj, new_name);
+       if (error) {
+               strlcpy(dev->bus_id, old_device_name, BUS_ID_SIZE);
+               goto out;
+       }
+
+#ifdef CONFIG_SYSFS_DEPRECATED
+       if (old_class_name) {
+               new_class_name = make_class_name(dev->class->name, &dev->kobj);
+               if (new_class_name) {
+                       error = sysfs_create_link(&dev->parent->kobj,
+                                                 &dev->kobj, new_class_name);
+                       if (error)
+                               goto out;
+                       sysfs_remove_link(&dev->parent->kobj, old_class_name);
+               }
+       }
+#endif
+
+       if (dev->class) {
+               sysfs_remove_link(&dev->class->subsys.kobj, old_device_name);
+               error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
+                                         dev->bus_id);
+               if (error) {
+                       /* Uh... how to unravel this if restoring can fail? */
+                       dev_err(dev, "%s: sysfs_create_symlink failed (%d)\n",
+                               __FUNCTION__, error);
+               }
+       }
+out:
+       put_device(dev);
+
+       kfree(new_class_name);
+       kfree(old_class_name);
+       kfree(old_device_name);
+
+       return error;
+}
+EXPORT_SYMBOL_GPL(device_rename);
+
+static int device_move_class_links(struct device *dev,
+                                  struct device *old_parent,
+                                  struct device *new_parent)
+{
+       int error = 0;
+#ifdef CONFIG_SYSFS_DEPRECATED
+       char *class_name;
+
+       class_name = make_class_name(dev->class->name, &dev->kobj);
+       if (!class_name) {
+               error = -ENOMEM;
+               goto out;
+       }
+       if (old_parent) {
+               sysfs_remove_link(&dev->kobj, "device");
+               sysfs_remove_link(&old_parent->kobj, class_name);
+       }
+       if (new_parent) {
+               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");
+       }
+       else
+               error = 0;
+out:
+       kfree(class_name);
+       return error;
+#else
+       if (old_parent)
+               sysfs_remove_link(&dev->kobj, "device");
+       if (new_parent)
+               error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
+                                         "device");
+       return error;
+#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 (can by NULL)
+ */
+int device_move(struct device *dev, struct device *new_parent)
+{
+       int error;
+       struct device *old_parent;
+       struct kobject *new_parent_kobj;
+
+       dev = get_device(dev);
+       if (!dev)
+               return -EINVAL;
+
+       new_parent = get_device(new_parent);
+       new_parent_kobj = get_device_parent (dev, new_parent);
+       if (IS_ERR(new_parent_kobj)) {
+               error = PTR_ERR(new_parent_kobj);
+               put_device(new_parent);
+               goto out;
+       }
+       pr_debug("DEVICE: moving '%s' to '%s'\n", dev->bus_id,
+                new_parent ? new_parent->bus_id : "<NULL>");
+       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);
+       if (new_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)) {
+                       if (new_parent)
+                               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);