forked from Minki/linux
bc451f2058
Move complete knowledge of namespaces into the kobject layer so we can use that information when reporting kobjects to userspace. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1819 lines
45 KiB
C
1819 lines
45 KiB
C
/*
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* drivers/base/core.c - core driver model code (device registration, etc)
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*
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* Copyright (c) 2002-3 Patrick Mochel
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* Copyright (c) 2002-3 Open Source Development Labs
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* Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de>
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* Copyright (c) 2006 Novell, Inc.
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*
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* This file is released under the GPLv2
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*
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*/
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/kdev_t.h>
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#include <linux/notifier.h>
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#include <linux/genhd.h>
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#include <linux/kallsyms.h>
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#include <linux/mutex.h>
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#include <linux/async.h>
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#include "base.h"
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#include "power/power.h"
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int (*platform_notify)(struct device *dev) = NULL;
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int (*platform_notify_remove)(struct device *dev) = NULL;
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static struct kobject *dev_kobj;
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struct kobject *sysfs_dev_char_kobj;
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struct kobject *sysfs_dev_block_kobj;
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#ifdef CONFIG_BLOCK
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static inline int device_is_not_partition(struct device *dev)
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{
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return !(dev->type == &part_type);
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}
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#else
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static inline int device_is_not_partition(struct device *dev)
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{
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return 1;
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}
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#endif
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/**
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* dev_driver_string - Return a device's driver name, if at all possible
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* @dev: struct device to get the name of
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*
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* Will return the device's driver's name if it is bound to a device. If
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* the device is not bound to a device, it will return the name of the bus
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* it is attached to. If it is not attached to a bus either, an empty
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* string will be returned.
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*/
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const char *dev_driver_string(const struct device *dev)
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{
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struct device_driver *drv;
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/* dev->driver can change to NULL underneath us because of unbinding,
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* so be careful about accessing it. dev->bus and dev->class should
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* never change once they are set, so they don't need special care.
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*/
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drv = ACCESS_ONCE(dev->driver);
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return drv ? drv->name :
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(dev->bus ? dev->bus->name :
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(dev->class ? dev->class->name : ""));
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}
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EXPORT_SYMBOL(dev_driver_string);
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#define to_dev(obj) container_of(obj, struct device, kobj)
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#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
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static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr,
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char *buf)
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{
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struct device_attribute *dev_attr = to_dev_attr(attr);
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struct device *dev = to_dev(kobj);
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ssize_t ret = -EIO;
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if (dev_attr->show)
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ret = dev_attr->show(dev, dev_attr, buf);
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if (ret >= (ssize_t)PAGE_SIZE) {
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print_symbol("dev_attr_show: %s returned bad count\n",
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(unsigned long)dev_attr->show);
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}
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return ret;
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}
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static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr,
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const char *buf, size_t count)
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{
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struct device_attribute *dev_attr = to_dev_attr(attr);
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struct device *dev = to_dev(kobj);
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ssize_t ret = -EIO;
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if (dev_attr->store)
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ret = dev_attr->store(dev, dev_attr, buf, count);
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return ret;
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}
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static const struct sysfs_ops dev_sysfs_ops = {
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.show = dev_attr_show,
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.store = dev_attr_store,
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};
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/**
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* device_release - free device structure.
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* @kobj: device's kobject.
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*
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* This is called once the reference count for the object
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* reaches 0. We forward the call to the device's release
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* method, which should handle actually freeing the structure.
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*/
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static void device_release(struct kobject *kobj)
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{
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struct device *dev = to_dev(kobj);
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struct device_private *p = dev->p;
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if (dev->release)
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dev->release(dev);
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else if (dev->type && dev->type->release)
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dev->type->release(dev);
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else if (dev->class && dev->class->dev_release)
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dev->class->dev_release(dev);
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else
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WARN(1, KERN_ERR "Device '%s' does not have a release() "
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"function, it is broken and must be fixed.\n",
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dev_name(dev));
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kfree(p);
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}
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static const void *device_namespace(struct kobject *kobj)
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{
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struct device *dev = to_dev(kobj);
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const void *ns = NULL;
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if (dev->class && dev->class->ns_type)
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ns = dev->class->namespace(dev);
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return ns;
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}
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static struct kobj_type device_ktype = {
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.release = device_release,
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.sysfs_ops = &dev_sysfs_ops,
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.namespace = device_namespace,
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};
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static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
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{
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struct kobj_type *ktype = get_ktype(kobj);
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if (ktype == &device_ktype) {
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struct device *dev = to_dev(kobj);
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if (dev->bus)
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return 1;
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if (dev->class)
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return 1;
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}
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return 0;
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}
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static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
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{
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struct device *dev = to_dev(kobj);
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if (dev->bus)
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return dev->bus->name;
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if (dev->class)
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return dev->class->name;
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return NULL;
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}
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static int dev_uevent(struct kset *kset, struct kobject *kobj,
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struct kobj_uevent_env *env)
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{
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struct device *dev = to_dev(kobj);
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int retval = 0;
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/* add device node properties if present */
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if (MAJOR(dev->devt)) {
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const char *tmp;
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const char *name;
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mode_t mode = 0;
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add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt));
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add_uevent_var(env, "MINOR=%u", MINOR(dev->devt));
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name = device_get_devnode(dev, &mode, &tmp);
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if (name) {
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add_uevent_var(env, "DEVNAME=%s", name);
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kfree(tmp);
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if (mode)
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add_uevent_var(env, "DEVMODE=%#o", mode & 0777);
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}
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}
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if (dev->type && dev->type->name)
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add_uevent_var(env, "DEVTYPE=%s", dev->type->name);
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if (dev->driver)
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add_uevent_var(env, "DRIVER=%s", dev->driver->name);
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#ifdef CONFIG_SYSFS_DEPRECATED
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if (dev->class) {
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struct device *parent = dev->parent;
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/* find first bus device in parent chain */
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while (parent && !parent->bus)
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parent = parent->parent;
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if (parent && parent->bus) {
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const char *path;
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path = kobject_get_path(&parent->kobj, GFP_KERNEL);
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if (path) {
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add_uevent_var(env, "PHYSDEVPATH=%s", path);
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kfree(path);
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}
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add_uevent_var(env, "PHYSDEVBUS=%s", parent->bus->name);
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if (parent->driver)
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add_uevent_var(env, "PHYSDEVDRIVER=%s",
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parent->driver->name);
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}
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} else if (dev->bus) {
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add_uevent_var(env, "PHYSDEVBUS=%s", dev->bus->name);
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if (dev->driver)
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add_uevent_var(env, "PHYSDEVDRIVER=%s",
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dev->driver->name);
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}
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#endif
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/* have the bus specific function add its stuff */
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if (dev->bus && dev->bus->uevent) {
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retval = dev->bus->uevent(dev, env);
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if (retval)
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pr_debug("device: '%s': %s: bus uevent() returned %d\n",
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dev_name(dev), __func__, retval);
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}
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/* have the class specific function add its stuff */
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if (dev->class && dev->class->dev_uevent) {
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retval = dev->class->dev_uevent(dev, env);
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if (retval)
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pr_debug("device: '%s': %s: class uevent() "
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"returned %d\n", dev_name(dev),
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__func__, retval);
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}
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/* have the device type specific fuction add its stuff */
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if (dev->type && dev->type->uevent) {
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retval = dev->type->uevent(dev, env);
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if (retval)
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pr_debug("device: '%s': %s: dev_type uevent() "
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"returned %d\n", dev_name(dev),
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__func__, retval);
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}
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return retval;
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}
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static const struct kset_uevent_ops device_uevent_ops = {
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.filter = dev_uevent_filter,
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.name = dev_uevent_name,
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.uevent = dev_uevent,
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};
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static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
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char *buf)
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{
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struct kobject *top_kobj;
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struct kset *kset;
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struct kobj_uevent_env *env = NULL;
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int i;
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size_t count = 0;
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int retval;
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/* search the kset, the device belongs to */
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top_kobj = &dev->kobj;
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while (!top_kobj->kset && top_kobj->parent)
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top_kobj = top_kobj->parent;
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if (!top_kobj->kset)
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goto out;
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kset = top_kobj->kset;
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if (!kset->uevent_ops || !kset->uevent_ops->uevent)
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goto out;
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/* respect filter */
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if (kset->uevent_ops && kset->uevent_ops->filter)
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if (!kset->uevent_ops->filter(kset, &dev->kobj))
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goto out;
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env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
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if (!env)
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return -ENOMEM;
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/* let the kset specific function add its keys */
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retval = kset->uevent_ops->uevent(kset, &dev->kobj, env);
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if (retval)
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goto out;
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/* copy keys to file */
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for (i = 0; i < env->envp_idx; i++)
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count += sprintf(&buf[count], "%s\n", env->envp[i]);
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out:
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kfree(env);
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return count;
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}
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static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
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const char *buf, size_t count)
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{
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enum kobject_action action;
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if (kobject_action_type(buf, count, &action) == 0)
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kobject_uevent(&dev->kobj, action);
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else
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dev_err(dev, "uevent: unknown action-string\n");
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return count;
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}
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static struct device_attribute uevent_attr =
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__ATTR(uevent, S_IRUGO | S_IWUSR, show_uevent, store_uevent);
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static int device_add_attributes(struct device *dev,
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struct device_attribute *attrs)
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{
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int error = 0;
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int i;
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if (attrs) {
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for (i = 0; attr_name(attrs[i]); i++) {
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error = device_create_file(dev, &attrs[i]);
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if (error)
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break;
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}
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if (error)
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while (--i >= 0)
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device_remove_file(dev, &attrs[i]);
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}
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return error;
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}
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static void device_remove_attributes(struct device *dev,
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struct device_attribute *attrs)
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{
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int i;
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if (attrs)
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for (i = 0; attr_name(attrs[i]); i++)
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device_remove_file(dev, &attrs[i]);
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}
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static int device_add_groups(struct device *dev,
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const struct attribute_group **groups)
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{
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int error = 0;
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int i;
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if (groups) {
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for (i = 0; groups[i]; i++) {
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error = sysfs_create_group(&dev->kobj, groups[i]);
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if (error) {
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while (--i >= 0)
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sysfs_remove_group(&dev->kobj,
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groups[i]);
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break;
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}
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}
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}
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return error;
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}
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static void device_remove_groups(struct device *dev,
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const struct attribute_group **groups)
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{
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int i;
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if (groups)
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for (i = 0; groups[i]; i++)
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sysfs_remove_group(&dev->kobj, groups[i]);
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}
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static int device_add_attrs(struct device *dev)
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{
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struct class *class = dev->class;
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struct device_type *type = dev->type;
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int error;
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if (class) {
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error = device_add_attributes(dev, class->dev_attrs);
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if (error)
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return error;
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}
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if (type) {
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error = device_add_groups(dev, type->groups);
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if (error)
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goto err_remove_class_attrs;
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}
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error = device_add_groups(dev, dev->groups);
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if (error)
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goto err_remove_type_groups;
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return 0;
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err_remove_type_groups:
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if (type)
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device_remove_groups(dev, type->groups);
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err_remove_class_attrs:
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if (class)
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device_remove_attributes(dev, class->dev_attrs);
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return error;
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}
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static void device_remove_attrs(struct device *dev)
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{
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struct class *class = dev->class;
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struct device_type *type = dev->type;
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device_remove_groups(dev, dev->groups);
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if (type)
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device_remove_groups(dev, type->groups);
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if (class)
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device_remove_attributes(dev, class->dev_attrs);
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}
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|
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static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
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char *buf)
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{
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return print_dev_t(buf, dev->devt);
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}
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static struct device_attribute devt_attr =
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__ATTR(dev, S_IRUGO, show_dev, NULL);
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/* kset to create /sys/devices/ */
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struct kset *devices_kset;
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/**
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* device_create_file - create sysfs attribute file for device.
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* @dev: device.
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* @attr: device attribute descriptor.
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*/
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int device_create_file(struct device *dev,
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const struct device_attribute *attr)
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{
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int error = 0;
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if (dev)
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error = sysfs_create_file(&dev->kobj, &attr->attr);
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return error;
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}
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|
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/**
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* device_remove_file - remove sysfs attribute file.
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* @dev: device.
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* @attr: device attribute descriptor.
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*/
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void device_remove_file(struct device *dev,
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const struct device_attribute *attr)
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{
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if (dev)
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sysfs_remove_file(&dev->kobj, &attr->attr);
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}
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|
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/**
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* device_create_bin_file - create sysfs binary attribute file for device.
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* @dev: device.
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* @attr: device binary attribute descriptor.
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*/
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int device_create_bin_file(struct device *dev,
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const struct bin_attribute *attr)
|
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{
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int error = -EINVAL;
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if (dev)
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error = sysfs_create_bin_file(&dev->kobj, attr);
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return error;
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}
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EXPORT_SYMBOL_GPL(device_create_bin_file);
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|
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/**
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* device_remove_bin_file - remove sysfs binary attribute file
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* @dev: device.
|
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* @attr: device binary attribute descriptor.
|
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*/
|
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void device_remove_bin_file(struct device *dev,
|
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const struct bin_attribute *attr)
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{
|
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if (dev)
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sysfs_remove_bin_file(&dev->kobj, attr);
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}
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EXPORT_SYMBOL_GPL(device_remove_bin_file);
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|
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/**
|
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* device_schedule_callback_owner - helper to schedule a callback for a device
|
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* @dev: device.
|
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* @func: callback function to invoke later.
|
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* @owner: module owning the callback routine
|
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*
|
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* Attribute methods must not unregister themselves or their parent device
|
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* (which would amount to the same thing). Attempts to do so will deadlock,
|
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* since unregistration is mutually exclusive with driver callbacks.
|
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*
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* Instead methods can call this routine, which will attempt to allocate
|
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* and schedule a workqueue request to call back @func with @dev as its
|
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* argument in the workqueue's process context. @dev will be pinned until
|
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* @func returns.
|
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*
|
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* This routine is usually called via the inline device_schedule_callback(),
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* which automatically sets @owner to THIS_MODULE.
|
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*
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* 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
|
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* underlying sysfs routine (since it is intended for use by attribute
|
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* 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)
|
|
{
|
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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_private *p = to_device_private_parent(n);
|
|
struct device *dev = p->device;
|
|
|
|
get_device(dev);
|
|
}
|
|
|
|
static void klist_children_put(struct klist_node *n)
|
|
{
|
|
struct device_private *p = to_device_private_parent(n);
|
|
struct device *dev = p->device;
|
|
|
|
put_device(dev);
|
|
}
|
|
|
|
/**
|
|
* device_initialize - init device structure.
|
|
* @dev: device.
|
|
*
|
|
* 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 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)
|
|
{
|
|
dev->kobj.kset = devices_kset;
|
|
kobject_init(&dev->kobj, &device_ktype);
|
|
INIT_LIST_HEAD(&dev->dma_pools);
|
|
mutex_init(&dev->mutex);
|
|
lockdep_set_novalidate_class(&dev->mutex);
|
|
spin_lock_init(&dev->devres_lock);
|
|
INIT_LIST_HEAD(&dev->devres_head);
|
|
device_pm_init(dev);
|
|
set_dev_node(dev, -1);
|
|
}
|
|
|
|
#ifdef CONFIG_SYSFS_DEPRECATED
|
|
static struct kobject *get_device_parent(struct device *dev,
|
|
struct device *parent)
|
|
{
|
|
/* class devices without a parent live in /sys/class/<classname>/ */
|
|
if (dev->class && (!parent || parent->class != dev->class))
|
|
return &dev->class->p->class_subsys.kobj;
|
|
/* all other devices keep their parent */
|
|
else if (parent)
|
|
return &parent->kobj;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static inline void cleanup_device_parent(struct device *dev) {}
|
|
static inline void cleanup_glue_dir(struct device *dev,
|
|
struct kobject *glue_dir) {}
|
|
#else
|
|
static struct kobject *virtual_device_parent(struct device *dev)
|
|
{
|
|
static struct kobject *virtual_dir = NULL;
|
|
|
|
if (!virtual_dir)
|
|
virtual_dir = kobject_create_and_add("virtual",
|
|
&devices_kset->kobj);
|
|
|
|
return virtual_dir;
|
|
}
|
|
|
|
struct class_dir {
|
|
struct kobject kobj;
|
|
struct class *class;
|
|
};
|
|
|
|
#define to_class_dir(obj) container_of(obj, struct class_dir, kobj)
|
|
|
|
static void class_dir_release(struct kobject *kobj)
|
|
{
|
|
struct class_dir *dir = to_class_dir(kobj);
|
|
kfree(dir);
|
|
}
|
|
|
|
static const
|
|
struct kobj_ns_type_operations *class_dir_child_ns_type(struct kobject *kobj)
|
|
{
|
|
struct class_dir *dir = to_class_dir(kobj);
|
|
return dir->class->ns_type;
|
|
}
|
|
|
|
static struct kobj_type class_dir_ktype = {
|
|
.release = class_dir_release,
|
|
.sysfs_ops = &kobj_sysfs_ops,
|
|
.child_ns_type = class_dir_child_ns_type
|
|
};
|
|
|
|
static struct kobject *
|
|
class_dir_create_and_add(struct class *class, struct kobject *parent_kobj)
|
|
{
|
|
struct class_dir *dir;
|
|
int retval;
|
|
|
|
dir = kzalloc(sizeof(*dir), GFP_KERNEL);
|
|
if (!dir)
|
|
return NULL;
|
|
|
|
dir->class = class;
|
|
kobject_init(&dir->kobj, &class_dir_ktype);
|
|
|
|
dir->kobj.kset = &class->p->class_dirs;
|
|
|
|
retval = kobject_add(&dir->kobj, parent_kobj, "%s", class->name);
|
|
if (retval < 0) {
|
|
kobject_put(&dir->kobj);
|
|
return NULL;
|
|
}
|
|
return &dir->kobj;
|
|
}
|
|
|
|
|
|
static struct kobject *get_device_parent(struct device *dev,
|
|
struct device *parent)
|
|
{
|
|
if (dev->class) {
|
|
static DEFINE_MUTEX(gdp_mutex);
|
|
struct kobject *kobj = NULL;
|
|
struct kobject *parent_kobj;
|
|
struct kobject *k;
|
|
|
|
/*
|
|
* If we have no parent, we live in "virtual".
|
|
* Class-devices with a non class-device as parent, live
|
|
* in a "glue" 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;
|
|
|
|
mutex_lock(&gdp_mutex);
|
|
|
|
/* find our class-directory at the parent and reference it */
|
|
spin_lock(&dev->class->p->class_dirs.list_lock);
|
|
list_for_each_entry(k, &dev->class->p->class_dirs.list, entry)
|
|
if (k->parent == parent_kobj) {
|
|
kobj = kobject_get(k);
|
|
break;
|
|
}
|
|
spin_unlock(&dev->class->p->class_dirs.list_lock);
|
|
if (kobj) {
|
|
mutex_unlock(&gdp_mutex);
|
|
return kobj;
|
|
}
|
|
|
|
/* or create a new class-directory at the parent device */
|
|
k = class_dir_create_and_add(dev->class, parent_kobj);
|
|
/* do not emit an uevent for this simple "glue" directory */
|
|
mutex_unlock(&gdp_mutex);
|
|
return k;
|
|
}
|
|
|
|
if (parent)
|
|
return &parent->kobj;
|
|
return NULL;
|
|
}
|
|
|
|
static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir)
|
|
{
|
|
/* see if we live in a "glue" directory */
|
|
if (!glue_dir || !dev->class ||
|
|
glue_dir->kset != &dev->class->p->class_dirs)
|
|
return;
|
|
|
|
kobject_put(glue_dir);
|
|
}
|
|
|
|
static void cleanup_device_parent(struct device *dev)
|
|
{
|
|
cleanup_glue_dir(dev, dev->kobj.parent);
|
|
}
|
|
#endif
|
|
|
|
static void setup_parent(struct device *dev, struct device *parent)
|
|
{
|
|
struct kobject *kobj;
|
|
kobj = get_device_parent(dev, parent);
|
|
if (kobj)
|
|
dev->kobj.parent = kobj;
|
|
}
|
|
|
|
static int device_add_class_symlinks(struct device *dev)
|
|
{
|
|
int error;
|
|
|
|
if (!dev->class)
|
|
return 0;
|
|
|
|
error = sysfs_create_link(&dev->kobj,
|
|
&dev->class->p->class_subsys.kobj,
|
|
"subsystem");
|
|
if (error)
|
|
goto out;
|
|
|
|
#ifdef CONFIG_SYSFS_DEPRECATED
|
|
/* stacked class devices need a symlink in the class directory */
|
|
if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
|
|
device_is_not_partition(dev)) {
|
|
error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
|
|
&dev->kobj, dev_name(dev));
|
|
if (error)
|
|
goto out_subsys;
|
|
}
|
|
|
|
if (dev->parent && device_is_not_partition(dev)) {
|
|
struct device *parent = dev->parent;
|
|
char *class_name;
|
|
|
|
/*
|
|
* stacked class devices have the 'device' link
|
|
* pointing to the bus device instead of the 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;
|
|
}
|
|
return 0;
|
|
|
|
out_device:
|
|
if (dev->parent && device_is_not_partition(dev))
|
|
sysfs_remove_link(&dev->kobj, "device");
|
|
out_busid:
|
|
if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
|
|
device_is_not_partition(dev))
|
|
sysfs_remove_link(&dev->class->p->class_subsys.kobj,
|
|
dev_name(dev));
|
|
#else
|
|
/* link in the class directory pointing to the device */
|
|
error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
|
|
&dev->kobj, dev_name(dev));
|
|
if (error)
|
|
goto out_subsys;
|
|
|
|
if (dev->parent && device_is_not_partition(dev)) {
|
|
error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
|
|
"device");
|
|
if (error)
|
|
goto out_busid;
|
|
}
|
|
return 0;
|
|
|
|
out_busid:
|
|
sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev_name(dev));
|
|
#endif
|
|
|
|
out_subsys:
|
|
sysfs_remove_link(&dev->kobj, "subsystem");
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
static void device_remove_class_symlinks(struct device *dev)
|
|
{
|
|
if (!dev->class)
|
|
return;
|
|
|
|
#ifdef CONFIG_SYSFS_DEPRECATED
|
|
if (dev->parent && device_is_not_partition(dev)) {
|
|
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);
|
|
}
|
|
sysfs_remove_link(&dev->kobj, "device");
|
|
}
|
|
|
|
if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
|
|
device_is_not_partition(dev))
|
|
sysfs_remove_link(&dev->class->p->class_subsys.kobj,
|
|
dev_name(dev));
|
|
#else
|
|
if (dev->parent && device_is_not_partition(dev))
|
|
sysfs_remove_link(&dev->kobj, "device");
|
|
|
|
sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev_name(dev));
|
|
#endif
|
|
|
|
sysfs_remove_link(&dev->kobj, "subsystem");
|
|
}
|
|
|
|
/**
|
|
* dev_set_name - set a device name
|
|
* @dev: device
|
|
* @fmt: format string for the device's name
|
|
*/
|
|
int dev_set_name(struct device *dev, const char *fmt, ...)
|
|
{
|
|
va_list vargs;
|
|
int err;
|
|
|
|
va_start(vargs, fmt);
|
|
err = kobject_set_name_vargs(&dev->kobj, fmt, vargs);
|
|
va_end(vargs);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dev_set_name);
|
|
|
|
/**
|
|
* device_to_dev_kobj - select a /sys/dev/ directory for the device
|
|
* @dev: device
|
|
*
|
|
* By default we select char/ for new entries. Setting class->dev_obj
|
|
* to NULL prevents an entry from being created. class->dev_kobj must
|
|
* be set (or cleared) before any devices are registered to the class
|
|
* otherwise device_create_sys_dev_entry() and
|
|
* device_remove_sys_dev_entry() will disagree about the the presence
|
|
* of the link.
|
|
*/
|
|
static struct kobject *device_to_dev_kobj(struct device *dev)
|
|
{
|
|
struct kobject *kobj;
|
|
|
|
if (dev->class)
|
|
kobj = dev->class->dev_kobj;
|
|
else
|
|
kobj = sysfs_dev_char_kobj;
|
|
|
|
return kobj;
|
|
}
|
|
|
|
static int device_create_sys_dev_entry(struct device *dev)
|
|
{
|
|
struct kobject *kobj = device_to_dev_kobj(dev);
|
|
int error = 0;
|
|
char devt_str[15];
|
|
|
|
if (kobj) {
|
|
format_dev_t(devt_str, dev->devt);
|
|
error = sysfs_create_link(kobj, &dev->kobj, devt_str);
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
static void device_remove_sys_dev_entry(struct device *dev)
|
|
{
|
|
struct kobject *kobj = device_to_dev_kobj(dev);
|
|
char devt_str[15];
|
|
|
|
if (kobj) {
|
|
format_dev_t(devt_str, dev->devt);
|
|
sysfs_remove_link(kobj, devt_str);
|
|
}
|
|
}
|
|
|
|
int device_private_init(struct device *dev)
|
|
{
|
|
dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL);
|
|
if (!dev->p)
|
|
return -ENOMEM;
|
|
dev->p->device = dev;
|
|
klist_init(&dev->p->klist_children, klist_children_get,
|
|
klist_children_put);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* device_add - add device to device hierarchy.
|
|
* @dev: device.
|
|
*
|
|
* This is part 2 of device_register(), though may be called
|
|
* separately _iff_ device_initialize() has been called separately.
|
|
*
|
|
* 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)
|
|
{
|
|
struct device *parent = NULL;
|
|
struct class_interface *class_intf;
|
|
int error = -EINVAL;
|
|
|
|
dev = get_device(dev);
|
|
if (!dev)
|
|
goto done;
|
|
|
|
if (!dev->p) {
|
|
error = device_private_init(dev);
|
|
if (error)
|
|
goto done;
|
|
}
|
|
|
|
/*
|
|
* for statically allocated devices, which should all be converted
|
|
* some day, we need to initialize the name. We prevent reading back
|
|
* the name, and force the use of dev_name()
|
|
*/
|
|
if (dev->init_name) {
|
|
dev_set_name(dev, "%s", dev->init_name);
|
|
dev->init_name = NULL;
|
|
}
|
|
|
|
if (!dev_name(dev)) {
|
|
error = -EINVAL;
|
|
goto name_error;
|
|
}
|
|
|
|
pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
|
|
|
|
parent = get_device(dev->parent);
|
|
setup_parent(dev, parent);
|
|
|
|
/* use parent numa_node */
|
|
if (parent)
|
|
set_dev_node(dev, dev_to_node(parent));
|
|
|
|
/* first, register with generic layer. */
|
|
/* we require the name to be set before, and pass NULL */
|
|
error = kobject_add(&dev->kobj, dev->kobj.parent, NULL);
|
|
if (error)
|
|
goto Error;
|
|
|
|
/* notify platform of device entry */
|
|
if (platform_notify)
|
|
platform_notify(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_create_sys_dev_entry(dev);
|
|
if (error)
|
|
goto devtattrError;
|
|
|
|
devtmpfs_create_node(dev);
|
|
}
|
|
|
|
error = device_add_class_symlinks(dev);
|
|
if (error)
|
|
goto SymlinkError;
|
|
error = device_add_attrs(dev);
|
|
if (error)
|
|
goto AttrsError;
|
|
error = bus_add_device(dev);
|
|
if (error)
|
|
goto BusError;
|
|
error = dpm_sysfs_add(dev);
|
|
if (error)
|
|
goto DPMError;
|
|
device_pm_add(dev);
|
|
|
|
/* Notify clients of device addition. This call must come
|
|
* after dpm_sysf_add() and before kobject_uevent().
|
|
*/
|
|
if (dev->bus)
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
BUS_NOTIFY_ADD_DEVICE, dev);
|
|
|
|
kobject_uevent(&dev->kobj, KOBJ_ADD);
|
|
bus_probe_device(dev);
|
|
if (parent)
|
|
klist_add_tail(&dev->p->knode_parent,
|
|
&parent->p->klist_children);
|
|
|
|
if (dev->class) {
|
|
mutex_lock(&dev->class->p->class_mutex);
|
|
/* tie the class to the device */
|
|
klist_add_tail(&dev->knode_class,
|
|
&dev->class->p->class_devices);
|
|
|
|
/* notify any interfaces that the device is here */
|
|
list_for_each_entry(class_intf,
|
|
&dev->class->p->class_interfaces, node)
|
|
if (class_intf->add_dev)
|
|
class_intf->add_dev(dev, class_intf);
|
|
mutex_unlock(&dev->class->p->class_mutex);
|
|
}
|
|
done:
|
|
put_device(dev);
|
|
return error;
|
|
DPMError:
|
|
bus_remove_device(dev);
|
|
BusError:
|
|
device_remove_attrs(dev);
|
|
AttrsError:
|
|
device_remove_class_symlinks(dev);
|
|
SymlinkError:
|
|
if (MAJOR(dev->devt))
|
|
devtmpfs_delete_node(dev);
|
|
if (MAJOR(dev->devt))
|
|
device_remove_sys_dev_entry(dev);
|
|
devtattrError:
|
|
if (MAJOR(dev->devt))
|
|
device_remove_file(dev, &devt_attr);
|
|
ueventattrError:
|
|
device_remove_file(dev, &uevent_attr);
|
|
attrError:
|
|
kobject_uevent(&dev->kobj, KOBJ_REMOVE);
|
|
kobject_del(&dev->kobj);
|
|
Error:
|
|
cleanup_device_parent(dev);
|
|
if (parent)
|
|
put_device(parent);
|
|
name_error:
|
|
kfree(dev->p);
|
|
dev->p = NULL;
|
|
goto done;
|
|
}
|
|
|
|
/**
|
|
* device_register - register a device with the system.
|
|
* @dev: pointer to the device structure
|
|
*
|
|
* This happens in two clean steps - initialize the device
|
|
* and add it to the system. The two steps can be called
|
|
* separately, but this is the easiest and most common.
|
|
* 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)
|
|
{
|
|
device_initialize(dev);
|
|
return device_add(dev);
|
|
}
|
|
|
|
/**
|
|
* get_device - increment reference count for device.
|
|
* @dev: device.
|
|
*
|
|
* This simply forwards the call to kobject_get(), though
|
|
* we do take care to provide for the case that we get a NULL
|
|
* pointer passed in.
|
|
*/
|
|
struct device *get_device(struct device *dev)
|
|
{
|
|
return dev ? to_dev(kobject_get(&dev->kobj)) : NULL;
|
|
}
|
|
|
|
/**
|
|
* put_device - decrement reference count.
|
|
* @dev: device in question.
|
|
*/
|
|
void put_device(struct device *dev)
|
|
{
|
|
/* might_sleep(); */
|
|
if (dev)
|
|
kobject_put(&dev->kobj);
|
|
}
|
|
|
|
/**
|
|
* device_del - delete device from system.
|
|
* @dev: device.
|
|
*
|
|
* This is the first part of the device unregistration
|
|
* sequence. This removes the device from the lists we control
|
|
* from here, has it removed from the other driver model
|
|
* subsystems it was added to in device_add(), and removes it
|
|
* from the kobject hierarchy.
|
|
*
|
|
* NOTE: this should be called manually _iff_ device_add() was
|
|
* also called manually.
|
|
*/
|
|
void device_del(struct device *dev)
|
|
{
|
|
struct device *parent = dev->parent;
|
|
struct class_interface *class_intf;
|
|
|
|
/* Notify clients of device removal. This call must come
|
|
* before dpm_sysfs_remove().
|
|
*/
|
|
if (dev->bus)
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
BUS_NOTIFY_DEL_DEVICE, dev);
|
|
device_pm_remove(dev);
|
|
dpm_sysfs_remove(dev);
|
|
if (parent)
|
|
klist_del(&dev->p->knode_parent);
|
|
if (MAJOR(dev->devt)) {
|
|
devtmpfs_delete_node(dev);
|
|
device_remove_sys_dev_entry(dev);
|
|
device_remove_file(dev, &devt_attr);
|
|
}
|
|
if (dev->class) {
|
|
device_remove_class_symlinks(dev);
|
|
|
|
mutex_lock(&dev->class->p->class_mutex);
|
|
/* notify any interfaces that the device is now gone */
|
|
list_for_each_entry(class_intf,
|
|
&dev->class->p->class_interfaces, node)
|
|
if (class_intf->remove_dev)
|
|
class_intf->remove_dev(dev, class_intf);
|
|
/* remove the device from the class list */
|
|
klist_del(&dev->knode_class);
|
|
mutex_unlock(&dev->class->p->class_mutex);
|
|
}
|
|
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);
|
|
kobject_uevent(&dev->kobj, KOBJ_REMOVE);
|
|
cleanup_device_parent(dev);
|
|
kobject_del(&dev->kobj);
|
|
put_device(parent);
|
|
}
|
|
|
|
/**
|
|
* device_unregister - unregister device from system.
|
|
* @dev: device going away.
|
|
*
|
|
* We do this in two parts, like we do device_register(). First,
|
|
* we remove it from all the subsystems with device_del(), then
|
|
* we decrement the reference count via put_device(). If that
|
|
* is the final reference count, the device will be cleaned up
|
|
* via device_release() above. Otherwise, the structure will
|
|
* stick around until the final reference to the device is dropped.
|
|
*/
|
|
void device_unregister(struct device *dev)
|
|
{
|
|
pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
|
|
device_del(dev);
|
|
put_device(dev);
|
|
}
|
|
|
|
static struct device *next_device(struct klist_iter *i)
|
|
{
|
|
struct klist_node *n = klist_next(i);
|
|
struct device *dev = NULL;
|
|
struct device_private *p;
|
|
|
|
if (n) {
|
|
p = to_device_private_parent(n);
|
|
dev = p->device;
|
|
}
|
|
return dev;
|
|
}
|
|
|
|
/**
|
|
* device_get_devnode - path of device node file
|
|
* @dev: device
|
|
* @mode: returned file access mode
|
|
* @tmp: possibly allocated string
|
|
*
|
|
* Return the relative path of a possible device node.
|
|
* Non-default names may need to allocate a memory to compose
|
|
* a name. This memory is returned in tmp and needs to be
|
|
* freed by the caller.
|
|
*/
|
|
const char *device_get_devnode(struct device *dev,
|
|
mode_t *mode, const char **tmp)
|
|
{
|
|
char *s;
|
|
|
|
*tmp = NULL;
|
|
|
|
/* the device type may provide a specific name */
|
|
if (dev->type && dev->type->devnode)
|
|
*tmp = dev->type->devnode(dev, mode);
|
|
if (*tmp)
|
|
return *tmp;
|
|
|
|
/* the class may provide a specific name */
|
|
if (dev->class && dev->class->devnode)
|
|
*tmp = dev->class->devnode(dev, mode);
|
|
if (*tmp)
|
|
return *tmp;
|
|
|
|
/* return name without allocation, tmp == NULL */
|
|
if (strchr(dev_name(dev), '!') == NULL)
|
|
return dev_name(dev);
|
|
|
|
/* replace '!' in the name with '/' */
|
|
*tmp = kstrdup(dev_name(dev), GFP_KERNEL);
|
|
if (!*tmp)
|
|
return NULL;
|
|
while ((s = strchr(*tmp, '!')))
|
|
s[0] = '/';
|
|
return *tmp;
|
|
}
|
|
|
|
/**
|
|
* device_for_each_child - device child iterator.
|
|
* @parent: parent struct device.
|
|
* @data: data for the callback.
|
|
* @fn: function to be called for each device.
|
|
*
|
|
* Iterate over @parent's child devices, and call @fn for each,
|
|
* passing it @data.
|
|
*
|
|
* We check the return of @fn each time. If it returns anything
|
|
* other than 0, we break out and return that value.
|
|
*/
|
|
int device_for_each_child(struct device *parent, void *data,
|
|
int (*fn)(struct device *dev, void *data))
|
|
{
|
|
struct klist_iter i;
|
|
struct device *child;
|
|
int error = 0;
|
|
|
|
if (!parent->p)
|
|
return 0;
|
|
|
|
klist_iter_init(&parent->p->klist_children, &i);
|
|
while ((child = next_device(&i)) && !error)
|
|
error = fn(child, data);
|
|
klist_iter_exit(&i);
|
|
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 *dev, void *data))
|
|
{
|
|
struct klist_iter i;
|
|
struct device *child;
|
|
|
|
if (!parent)
|
|
return NULL;
|
|
|
|
klist_iter_init(&parent->p->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)
|
|
{
|
|
devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL);
|
|
if (!devices_kset)
|
|
return -ENOMEM;
|
|
dev_kobj = kobject_create_and_add("dev", NULL);
|
|
if (!dev_kobj)
|
|
goto dev_kobj_err;
|
|
sysfs_dev_block_kobj = kobject_create_and_add("block", dev_kobj);
|
|
if (!sysfs_dev_block_kobj)
|
|
goto block_kobj_err;
|
|
sysfs_dev_char_kobj = kobject_create_and_add("char", dev_kobj);
|
|
if (!sysfs_dev_char_kobj)
|
|
goto char_kobj_err;
|
|
|
|
return 0;
|
|
|
|
char_kobj_err:
|
|
kobject_put(sysfs_dev_block_kobj);
|
|
block_kobj_err:
|
|
kobject_put(dev_kobj);
|
|
dev_kobj_err:
|
|
kset_unregister(devices_kset);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_for_each_child);
|
|
EXPORT_SYMBOL_GPL(device_find_child);
|
|
|
|
EXPORT_SYMBOL_GPL(device_initialize);
|
|
EXPORT_SYMBOL_GPL(device_add);
|
|
EXPORT_SYMBOL_GPL(device_register);
|
|
|
|
EXPORT_SYMBOL_GPL(device_del);
|
|
EXPORT_SYMBOL_GPL(device_unregister);
|
|
EXPORT_SYMBOL_GPL(get_device);
|
|
EXPORT_SYMBOL_GPL(put_device);
|
|
|
|
EXPORT_SYMBOL_GPL(device_create_file);
|
|
EXPORT_SYMBOL_GPL(device_remove_file);
|
|
|
|
struct root_device
|
|
{
|
|
struct device dev;
|
|
struct module *owner;
|
|
};
|
|
|
|
#define to_root_device(dev) container_of(dev, struct root_device, dev)
|
|
|
|
static void root_device_release(struct device *dev)
|
|
{
|
|
kfree(to_root_device(dev));
|
|
}
|
|
|
|
/**
|
|
* __root_device_register - allocate and register a root device
|
|
* @name: root device name
|
|
* @owner: owner module of the root device, usually THIS_MODULE
|
|
*
|
|
* This function allocates a root device and registers it
|
|
* using device_register(). In order to free the returned
|
|
* device, use root_device_unregister().
|
|
*
|
|
* Root devices are dummy devices which allow other devices
|
|
* to be grouped under /sys/devices. Use this function to
|
|
* allocate a root device and then use it as the parent of
|
|
* any device which should appear under /sys/devices/{name}
|
|
*
|
|
* The /sys/devices/{name} directory will also contain a
|
|
* 'module' symlink which points to the @owner directory
|
|
* in sysfs.
|
|
*
|
|
* Returns &struct device pointer on success, or ERR_PTR() on error.
|
|
*
|
|
* Note: You probably want to use root_device_register().
|
|
*/
|
|
struct device *__root_device_register(const char *name, struct module *owner)
|
|
{
|
|
struct root_device *root;
|
|
int err = -ENOMEM;
|
|
|
|
root = kzalloc(sizeof(struct root_device), GFP_KERNEL);
|
|
if (!root)
|
|
return ERR_PTR(err);
|
|
|
|
err = dev_set_name(&root->dev, "%s", name);
|
|
if (err) {
|
|
kfree(root);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
root->dev.release = root_device_release;
|
|
|
|
err = device_register(&root->dev);
|
|
if (err) {
|
|
put_device(&root->dev);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
#ifdef CONFIG_MODULE /* gotta find a "cleaner" way to do this */
|
|
if (owner) {
|
|
struct module_kobject *mk = &owner->mkobj;
|
|
|
|
err = sysfs_create_link(&root->dev.kobj, &mk->kobj, "module");
|
|
if (err) {
|
|
device_unregister(&root->dev);
|
|
return ERR_PTR(err);
|
|
}
|
|
root->owner = owner;
|
|
}
|
|
#endif
|
|
|
|
return &root->dev;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__root_device_register);
|
|
|
|
/**
|
|
* root_device_unregister - unregister and free a root device
|
|
* @dev: device going away
|
|
*
|
|
* This function unregisters and cleans up a device that was created by
|
|
* root_device_register().
|
|
*/
|
|
void root_device_unregister(struct device *dev)
|
|
{
|
|
struct root_device *root = to_root_device(dev);
|
|
|
|
if (root->owner)
|
|
sysfs_remove_link(&root->dev.kobj, "module");
|
|
|
|
device_unregister(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(root_device_unregister);
|
|
|
|
|
|
static void device_create_release(struct device *dev)
|
|
{
|
|
pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
|
|
kfree(dev);
|
|
}
|
|
|
|
/**
|
|
* device_create_vargs - 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
|
|
* @drvdata: the data to be added to the device for callbacks
|
|
* @fmt: string for the device's name
|
|
* @args: va_list 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.
|
|
*
|
|
* Returns &struct device pointer on success, or ERR_PTR() on error.
|
|
*
|
|
* Note: the struct class passed to this function must have previously
|
|
* been created with a call to class_create().
|
|
*/
|
|
struct device *device_create_vargs(struct class *class, struct device *parent,
|
|
dev_t devt, void *drvdata, 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;
|
|
dev_set_drvdata(dev, drvdata);
|
|
|
|
retval = kobject_set_name_vargs(&dev->kobj, fmt, args);
|
|
if (retval)
|
|
goto error;
|
|
|
|
retval = device_register(dev);
|
|
if (retval)
|
|
goto error;
|
|
|
|
return dev;
|
|
|
|
error:
|
|
put_device(dev);
|
|
return ERR_PTR(retval);
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_create_vargs);
|
|
|
|
/**
|
|
* 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
|
|
* @drvdata: the data to be added to the device for callbacks
|
|
* @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.
|
|
*
|
|
* Returns &struct device pointer on success, or ERR_PTR() on error.
|
|
*
|
|
* 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, void *drvdata, const char *fmt, ...)
|
|
{
|
|
va_list vargs;
|
|
struct device *dev;
|
|
|
|
va_start(vargs, fmt);
|
|
dev = device_create_vargs(class, parent, devt, drvdata, fmt, vargs);
|
|
va_end(vargs);
|
|
return dev;
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_create);
|
|
|
|
static int __match_devt(struct device *dev, void *data)
|
|
{
|
|
dev_t *devt = data;
|
|
|
|
return dev->devt == *devt;
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
|
|
dev = class_find_device(class, NULL, &devt, __match_devt);
|
|
if (dev) {
|
|
put_device(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
|
|
*
|
|
* 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)
|
|
{
|
|
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: '%s': %s: renaming to '%s'\n", dev_name(dev),
|
|
__func__, 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 = kstrdup(dev_name(dev), GFP_KERNEL);
|
|
if (!old_device_name) {
|
|
error = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
error = kobject_rename(&dev->kobj, new_name);
|
|
if (error)
|
|
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_rename_link(&dev->parent->kobj,
|
|
&dev->kobj,
|
|
old_class_name,
|
|
new_class_name);
|
|
}
|
|
}
|
|
#else
|
|
if (dev->class) {
|
|
error = sysfs_rename_link(&dev->class->p->class_subsys.kobj,
|
|
&dev->kobj, old_device_name, new_name);
|
|
}
|
|
#endif
|
|
|
|
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)
|
|
* @dpm_order: how to reorder the dpm_list
|
|
*/
|
|
int device_move(struct device *dev, struct device *new_parent,
|
|
enum dpm_order dpm_order)
|
|
{
|
|
int error;
|
|
struct device *old_parent;
|
|
struct kobject *new_parent_kobj;
|
|
|
|
dev = get_device(dev);
|
|
if (!dev)
|
|
return -EINVAL;
|
|
|
|
device_pm_lock();
|
|
new_parent = get_device(new_parent);
|
|
new_parent_kobj = get_device_parent(dev, new_parent);
|
|
|
|
pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev),
|
|
__func__, new_parent ? dev_name(new_parent) : "<NULL>");
|
|
error = kobject_move(&dev->kobj, new_parent_kobj);
|
|
if (error) {
|
|
cleanup_glue_dir(dev, new_parent_kobj);
|
|
put_device(new_parent);
|
|
goto out;
|
|
}
|
|
old_parent = dev->parent;
|
|
dev->parent = new_parent;
|
|
if (old_parent)
|
|
klist_remove(&dev->p->knode_parent);
|
|
if (new_parent) {
|
|
klist_add_tail(&dev->p->knode_parent,
|
|
&new_parent->p->klist_children);
|
|
set_dev_node(dev, dev_to_node(new_parent));
|
|
}
|
|
|
|
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->p->knode_parent);
|
|
dev->parent = old_parent;
|
|
if (old_parent) {
|
|
klist_add_tail(&dev->p->knode_parent,
|
|
&old_parent->p->klist_children);
|
|
set_dev_node(dev, dev_to_node(old_parent));
|
|
}
|
|
}
|
|
cleanup_glue_dir(dev, new_parent_kobj);
|
|
put_device(new_parent);
|
|
goto out;
|
|
}
|
|
switch (dpm_order) {
|
|
case DPM_ORDER_NONE:
|
|
break;
|
|
case DPM_ORDER_DEV_AFTER_PARENT:
|
|
device_pm_move_after(dev, new_parent);
|
|
break;
|
|
case DPM_ORDER_PARENT_BEFORE_DEV:
|
|
device_pm_move_before(new_parent, dev);
|
|
break;
|
|
case DPM_ORDER_DEV_LAST:
|
|
device_pm_move_last(dev);
|
|
break;
|
|
}
|
|
out_put:
|
|
put_device(old_parent);
|
|
out:
|
|
device_pm_unlock();
|
|
put_device(dev);
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_move);
|
|
|
|
/**
|
|
* device_shutdown - call ->shutdown() on each device to shutdown.
|
|
*/
|
|
void device_shutdown(void)
|
|
{
|
|
struct device *dev;
|
|
|
|
spin_lock(&devices_kset->list_lock);
|
|
/*
|
|
* Walk the devices list backward, shutting down each in turn.
|
|
* Beware that device unplug events may also start pulling
|
|
* devices offline, even as the system is shutting down.
|
|
*/
|
|
while (!list_empty(&devices_kset->list)) {
|
|
dev = list_entry(devices_kset->list.prev, struct device,
|
|
kobj.entry);
|
|
get_device(dev);
|
|
/*
|
|
* Make sure the device is off the kset list, in the
|
|
* event that dev->*->shutdown() doesn't remove it.
|
|
*/
|
|
list_del_init(&dev->kobj.entry);
|
|
spin_unlock(&devices_kset->list_lock);
|
|
|
|
if (dev->bus && dev->bus->shutdown) {
|
|
dev_dbg(dev, "shutdown\n");
|
|
dev->bus->shutdown(dev);
|
|
} else if (dev->driver && dev->driver->shutdown) {
|
|
dev_dbg(dev, "shutdown\n");
|
|
dev->driver->shutdown(dev);
|
|
}
|
|
put_device(dev);
|
|
|
|
spin_lock(&devices_kset->list_lock);
|
|
}
|
|
spin_unlock(&devices_kset->list_lock);
|
|
async_synchronize_full();
|
|
}
|