| /* |
| * drivers/base/core.c - core driver model code (device registration, etc) |
| * |
| * 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/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> |
| |
| #include "base.h" |
| #include "power/power.h" |
| |
| int (*platform_notify)(struct device * dev) = NULL; |
| 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) |
| |
| static ssize_t |
| dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf) |
| { |
| struct device_attribute * dev_attr = to_dev_attr(attr); |
| struct device * dev = to_dev(kobj); |
| ssize_t ret = -EIO; |
| |
| if (dev_attr->show) |
| ret = dev_attr->show(dev, dev_attr, buf); |
| return ret; |
| } |
| |
| static ssize_t |
| dev_attr_store(struct kobject * kobj, struct attribute * attr, |
| const char * buf, size_t count) |
| { |
| struct device_attribute * dev_attr = to_dev_attr(attr); |
| struct device * dev = to_dev(kobj); |
| ssize_t ret = -EIO; |
| |
| if (dev_attr->store) |
| ret = dev_attr->store(dev, dev_attr, buf, count); |
| return ret; |
| } |
| |
| static struct sysfs_ops dev_sysfs_ops = { |
| .show = dev_attr_show, |
| .store = dev_attr_store, |
| }; |
| |
| |
| /** |
| * device_release - free device structure. |
| * @kobj: device's kobject. |
| * |
| * This is called once the reference count for the object |
| * reaches 0. We forward the call to the device's release |
| * method, which should handle actually freeing the structure. |
| */ |
| static void device_release(struct kobject * kobj) |
| { |
| struct device * dev = to_dev(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", |
| dev->bus_id); |
| WARN_ON(1); |
| } |
| } |
| |
| static struct kobj_type device_ktype = { |
| .release = device_release, |
| .sysfs_ops = &dev_sysfs_ops, |
| }; |
| |
| |
| static int dev_uevent_filter(struct kset *kset, struct kobject *kobj) |
| { |
| struct kobj_type *ktype = get_ktype(kobj); |
| |
| 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; |
| } |
| |
| static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj) |
| { |
| struct device *dev = to_dev(kobj); |
| |
| 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, |
| struct kobj_uevent_env *env) |
| { |
| struct device *dev = to_dev(kobj); |
| int retval = 0; |
| |
| /* 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); |
| |
| if (dev->driver) |
| 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); |
| |
| 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) { |
| 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; |
| } |
| |
| static struct kset_uevent_ops device_uevent_ops = { |
| .filter = dev_uevent_filter, |
| .name = dev_uevent_name, |
| .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, &device_uevent_ops); |
| |
| |
| /** |
| * device_create_file - create sysfs attribute file for device. |
| * @dev: device. |
| * @attr: device attribute descriptor. |
| */ |
| |
| int device_create_file(struct device * dev, struct device_attribute * attr) |
| { |
| int error = 0; |
| if (get_device(dev)) { |
| error = sysfs_create_file(&dev->kobj, &attr->attr); |
| put_device(dev); |
| } |
| return error; |
| } |
| |
| /** |
| * device_remove_file - remove sysfs attribute file. |
| * @dev: device. |
| * @attr: device attribute descriptor. |
| */ |
| |
| void device_remove_file(struct device * dev, struct device_attribute * attr) |
| { |
| if (get_device(dev)) { |
| sysfs_remove_file(&dev->kobj, &attr->attr); |
| put_device(dev); |
| } |
| } |
| |
| /** |
| * 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); |
| |
| get_device(dev); |
| } |
| |
| static void klist_children_put(struct klist_node *n) |
| { |
| struct device *dev = container_of(n, struct device, knode_parent); |
| |
| put_device(dev); |
| } |
| |
| |
| /** |
| * device_initialize - init device structure. |
| * @dev: device. |
| * |
| * This prepares the device for use by other layers, |
| * including adding it to the device hierarchy. |
| * It is the first half of device_register(), if called by |
| * that, though it can also be called separately, so one |
| * may use @dev's fields (e.g. the refcount). |
| */ |
| |
| void device_initialize(struct device *dev) |
| { |
| dev->kobj.kset = &devices_subsys; |
| dev->kobj.ktype = &device_ktype; |
| kobject_init(&dev->kobj); |
| 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"); |
| } |
| |
| /** |
| * 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 it 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. |
| */ |
| int device_add(struct device *dev) |
| { |
| struct device *parent = NULL; |
| struct class_interface *class_intf; |
| int error; |
| |
| error = pm_sleep_lock(); |
| if (error) { |
| dev_warn(dev, "Suspicious %s during suspend\n", __FUNCTION__); |
| dump_stack(); |
| return error; |
| } |
| |
| dev = get_device(dev); |
| if (!dev || !strlen(dev->bus_id)) { |
| error = -EINVAL; |
| goto Error; |
| } |
| |
| 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); |
| error = kobject_add(&dev->kobj); |
| if (error) |
| goto Error; |
| |
| /* notify platform of device entry */ |
| if (platform_notify) |
| platform_notify(dev); |
| |
| /* notify clients of device entry (new way) */ |
| if (dev->bus) |
| blocking_notifier_call_chain(&dev->bus->bus_notifier, |
| BUS_NOTIFY_ADD_DEVICE, dev); |
| |
| 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 = dpm_sysfs_add(dev); |
| if (error) |
| goto PMError; |
| device_pm_add(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); |
| |
| 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); |
| pm_sleep_unlock(); |
| return error; |
| BusError: |
| device_pm_remove(dev); |
| dpm_sysfs_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: |
| if (parent) |
| put_device(parent); |
| 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. |
| */ |
| |
| 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) |
| { |
| 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; |
| |
| device_pm_remove(dev); |
| if (parent) |
| klist_del(&dev->knode_parent); |
| 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); |
| if (dev->bus) |
| blocking_notifier_call_chain(&dev->bus->bus_notifier, |
| BUS_NOTIFY_DEL_DEVICE, dev); |
| kobject_uevent(&dev->kobj, KOBJ_REMOVE); |
| kobject_del(&dev->kobj); |
| if (parent) |
| 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("DEV: Unregistering device. ID = '%s'\n", dev->bus_id); |
| device_del(dev); |
| put_device(dev); |
| } |
| |
| |
| static struct device * next_device(struct klist_iter * i) |
| { |
| struct klist_node * n = klist_next(i); |
| return n ? container_of(n, struct device, knode_parent) : NULL; |
| } |
| |
| /** |
| * 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 *, void *)) |
| { |
| struct klist_iter i; |
| struct device * child; |
| int error = 0; |
| |
| klist_iter_init(&parent->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 *, 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); |
| 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); |
| |
| |
| 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); |
| |
| /** |
| * find_device - finds 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 |
| */ |
| static struct device *find_device(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); |
| return dev; |
| } |
| |
| /** |
| * 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 = find_device(class, devt); |
| if (dev) |
| device_unregister(dev); |
| } |
| EXPORT_SYMBOL_GPL(device_destroy); |
| |
| #ifdef CONFIG_PM_SLEEP |
| /** |
| * destroy_suspended_device - asks the PM core to remove a suspended device |
| * @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 notifies the PM core of the necessity to unregister a suspended |
| * device created with a call to device_create() (devices cannot be |
| * unregistered directly while suspended, since the PM core holds their |
| * semaphores at that time). |
| * |
| * It can only be called within the scope of a system sleep transition. In |
| * practice this means it has to be directly or indirectly invoked either by |
| * a suspend or resume method, or by the PM core (e.g. via |
| * disable_nonboot_cpus() or enable_nonboot_cpus()). |
| */ |
| void destroy_suspended_device(struct class *class, dev_t devt) |
| { |
| struct device *dev; |
| |
| dev = find_device(class, devt); |
| if (dev) |
| device_pm_schedule_removal(dev); |
| } |
| EXPORT_SYMBOL_GPL(destroy_suspended_device); |
| #endif /* CONFIG_PM_SLEEP */ |
| |
| /** |
| * 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); |
| } |
| } |
| #else |
| 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) { |
| dev_err(dev, "%s: sysfs_create_symlink failed (%d)\n", |
| __FUNCTION__, error); |
| } |
| } |
| #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) |
| */ |
| 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); |