/* * bus.c - bus driver management * * Copyright (c) 2002-3 Patrick Mochel * Copyright (c) 2002-3 Open Source Development Labs * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de> * Copyright (c) 2007 Novell Inc. * * This file is released under the GPLv2 * */ #include <linux/device.h>#include <linux/module.h>#include <linux/errno.h>#include <linux/slab.h>#include <linux/init.h>#include <linux/string.h>#include <linux/mutex.h>#include <linux/sysfs.h>#include "base.h"#include "power/power.h" /* /sys/devices/system */static struct kset *system_kset; #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) /* * sysfs bindings for drivers */ #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) static int __must_check bus_rescan_devices_helper(struct device *dev, void *data); static struct bus_type *bus_get(struct bus_type *bus){ if (bus) { kset_get(&bus->p->subsys); return bus; } return NULL;} static void bus_put(struct bus_type *bus){ if (bus) kset_put(&bus->p->subsys);} static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, char *buf){ struct driver_attribute *drv_attr = to_drv_attr(attr); struct driver_private *drv_priv = to_driver(kobj); ssize_t ret = -EIO; if (drv_attr->show) ret = drv_attr->show(drv_priv->driver, buf); return ret;} static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count){ struct driver_attribute *drv_attr = to_drv_attr(attr); struct driver_private *drv_priv = to_driver(kobj); ssize_t ret = -EIO; if (drv_attr->store) ret = drv_attr->store(drv_priv->driver, buf, count); return ret;} static const struct sysfs_ops driver_sysfs_ops = { .show = drv_attr_show, .store = drv_attr_store,}; static void driver_release(struct kobject *kobj){ struct driver_private *drv_priv = to_driver(kobj); pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); kfree(drv_priv);} static struct kobj_type driver_ktype = { .sysfs_ops = &driver_sysfs_ops, .release = driver_release,}; /* * sysfs bindings for buses */static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, char *buf){ struct bus_attribute *bus_attr = to_bus_attr(attr); struct subsys_private *subsys_priv = to_subsys_private(kobj); ssize_t ret = 0; if (bus_attr->show) ret = bus_attr->show(subsys_priv->bus, buf); return ret;} static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count){ struct bus_attribute *bus_attr = to_bus_attr(attr); struct subsys_private *subsys_priv = to_subsys_private(kobj); ssize_t ret = 0; if (bus_attr->store) ret = bus_attr->store(subsys_priv->bus, buf, count); return ret;} static const struct sysfs_ops bus_sysfs_ops = { .show = bus_attr_show, .store = bus_attr_store,}; int bus_create_file(struct bus_type *bus, struct bus_attribute *attr){ int error; if (bus_get(bus)) { error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); bus_put(bus); } else error = -EINVAL; return error;}EXPORT_SYMBOL_GPL(bus_create_file); void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr){ if (bus_get(bus)) { sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); bus_put(bus); }}EXPORT_SYMBOL_GPL(bus_remove_file); static struct kobj_type bus_ktype = { .sysfs_ops = &bus_sysfs_ops,}; static int bus_uevent_filter(struct kset *kset, struct kobject *kobj){ struct kobj_type *ktype = get_ktype(kobj); if (ktype == &bus_ktype) return 1; return 0;} static const struct kset_uevent_ops bus_uevent_ops = { .filter = bus_uevent_filter,}; static struct kset *bus_kset; /* Manually detach a device from its associated driver. */static ssize_t unbind_store(struct device_driver *drv, const char *buf, size_t count){ struct bus_type *bus = bus_get(drv->bus); struct device *dev; int err = -ENODEV; dev = bus_find_device_by_name(bus, NULL, buf); if (dev && dev->driver == drv) { if (dev->parent) /* Needed for USB */ device_lock(dev->parent); device_release_driver(dev); if (dev->parent) device_unlock(dev->parent); err = count; } put_device(dev); bus_put(bus); return err;}static DRIVER_ATTR_WO(unbind); /* * Manually attach a device to a driver. * Note: the driver must want to bind to the device, * it is not possible to override the driver's id table. */static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t count){ struct bus_type *bus = bus_get(drv->bus); struct device *dev; int err = -ENODEV; dev = bus_find_device_by_name(bus, NULL, buf); if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { if (dev->parent) /* Needed for USB */ device_lock(dev->parent); device_lock(dev); err = driver_probe_device(drv, dev); device_unlock(dev); if (dev->parent) device_unlock(dev->parent); if (err > 0) { /* success */ err = count; } else if (err == 0) { /* driver didn't accept device */ err = -ENODEV; } } put_device(dev); bus_put(bus); return err;}static DRIVER_ATTR_WO(bind); static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf){ return sprintf(buf, "%d\n", bus->p->drivers_autoprobe);} static ssize_t store_drivers_autoprobe(struct bus_type *bus, const char *buf, size_t count){ if (buf[0] == '0') bus->p->drivers_autoprobe = 0; else bus->p->drivers_autoprobe = 1; return count;} static ssize_t store_drivers_probe(struct bus_type *bus, const char *buf, size_t count){ struct device *dev; dev = bus_find_device_by_name(bus, NULL, buf); if (!dev) return -ENODEV; if (bus_rescan_devices_helper(dev, NULL) != 0) return -EINVAL; return count;} static struct device *next_device(struct klist_iter *i){ struct klist_node *n = klist_next(i); struct device *dev = NULL; struct device_private *dev_prv; if (n) { dev_prv = to_device_private_bus(n); dev = dev_prv->device; } return dev;} /** * bus_for_each_dev - device iterator. * @bus: bus type. * @start: device to start iterating from. * @data: data for the callback. * @fn: function to be called for each device. * * Iterate over @bus's list of devices, and call @fn for each, * passing it @data. If @start is not NULL, we use that device to * begin iterating from. * * We check the return of @fn each time. If it returns anything * other than 0, we break out and return that value. * * NOTE: The device that returns a non-zero value is not retained * in any way, nor is its refcount incremented. If the caller needs * to retain this data, it should do so, and increment the reference * count in the supplied callback. */int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data, int (*fn)(struct device *, void *)){ struct klist_iter i; struct device *dev; int error = 0; if (!bus || !bus->p) return -EINVAL; klist_iter_init_node(&bus->p->klist_devices, &i, (start ? &start->p->knode_bus : NULL)); while ((dev = next_device(&i)) && !error) error = fn(dev, data); klist_iter_exit(&i); return error;}EXPORT_SYMBOL_GPL(bus_for_each_dev); /** * bus_find_device - device iterator for locating a particular device. * @bus: bus type * @start: Device to begin with * @data: Data to pass to match function * @match: Callback function to check device * * This is similar to the bus_for_each_dev() 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, this function will * return to the caller and not iterate over any more devices. */struct device *bus_find_device(struct bus_type *bus, struct device *start, void *data, int (*match)(struct device *dev, void *data)){ struct klist_iter i; struct device *dev; if (!bus || !bus->p) return NULL; klist_iter_init_node(&bus->p->klist_devices, &i, (start ? &start->p->knode_bus : NULL)); while ((dev = next_device(&i))) if (match(dev, data) && get_device(dev)) break; klist_iter_exit(&i); return dev;}EXPORT_SYMBOL_GPL(bus_find_device); static int match_name(struct device *dev, void *data){ const char *name = data; return sysfs_streq(name, dev_name(dev));} /** * bus_find_device_by_name - device iterator for locating a particular device of a specific name * @bus: bus type * @start: Device to begin with * @name: name of the device to match * * This is similar to the bus_find_device() function above, but it handles * searching by a name automatically, no need to write another strcmp matching * function. */struct device *bus_find_device_by_name(struct bus_type *bus, struct device *start, const char *name){ return bus_find_device(bus, start, (void *)name, match_name);}EXPORT_SYMBOL_GPL(bus_find_device_by_name); /** * subsys_find_device_by_id - find a device with a specific enumeration number * @subsys: subsystem * @id: index 'id' in struct device * @hint: device to check first * * Check the hint's next object and if it is a match return it directly, * otherwise, fall back to a full list search. Either way a reference for * the returned object is taken. */struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id, struct device *hint){ struct klist_iter i; struct device *dev; if (!subsys) return NULL; if (hint) { klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus); dev = next_device(&i); if (dev && dev->id == id && get_device(dev)) { klist_iter_exit(&i); return dev; } klist_iter_exit(&i); } klist_iter_init_node(&subsys->p->klist_devices, &i, NULL); while ((dev = next_device(&i))) { if (dev->id == id && get_device(dev)) { klist_iter_exit(&i); return dev; } } klist_iter_exit(&i); return NULL;}EXPORT_SYMBOL_GPL(subsys_find_device_by_id); static struct device_driver *next_driver(struct klist_iter *i){ struct klist_node *n = klist_next(i); struct driver_private *drv_priv; if (n) { drv_priv = container_of(n, struct driver_private, knode_bus); return drv_priv->driver; } return NULL;} /** * bus_for_each_drv - driver iterator * @bus: bus we're dealing with. * @start: driver to start iterating on. * @data: data to pass to the callback. * @fn: function to call for each driver. * * This is nearly identical to the device iterator above. * We iterate over each driver that belongs to @bus, and call * @fn for each. If @fn returns anything but 0, we break out * and return it. If @start is not NULL, we use it as the head * of the list. * * NOTE: we don't return the driver that returns a non-zero * value, nor do we leave the reference count incremented for that * driver. If the caller needs to know that info, it must set it * in the callback. It must also be sure to increment the refcount * so it doesn't disappear before returning to the caller. */int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, void *data, int (*fn)(struct device_driver *, void *)){ struct klist_iter i; struct device_driver *drv; int error = 0; if (!bus) return -EINVAL; klist_iter_init_node(&bus->p->klist_drivers, &i, start ? &start->p->knode_bus : NULL); while ((drv = next_driver(&i)) && !error) error = fn(drv, data); klist_iter_exit(&i); return error;}EXPORT_SYMBOL_GPL(bus_for_each_drv); static int device_add_attrs(struct bus_type *bus, struct device *dev){ int error = 0; int i; if (!bus->dev_attrs) return 0; for (i = 0; bus->dev_attrs[i].attr.name; i++) { error = device_create_file(dev, &bus->dev_attrs[i]); if (error) { while (--i >= 0) device_remove_file(dev, &bus->dev_attrs[i]); break; } } return error;} static void device_remove_attrs(struct bus_type *bus, struct device *dev){ int i; if (bus->dev_attrs) { for (i = 0; bus->dev_attrs[i].attr.name; i++) device_remove_file(dev, &bus->dev_attrs[i]); }} /** * bus_add_device - add device to bus * @dev: device being added * * - Add device's bus attributes. * - Create links to device's bus. * - Add the device to its bus's list of devices. */int bus_add_device(struct device *dev){ struct bus_type *bus = bus_get(dev->bus); int error = 0; if (bus) { pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); error = device_add_attrs(bus, dev);Lines 1–500 of 1263. 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/* * bus.c - bus driver management * * Copyright (c) 2002-3 Patrick Mochel * Copyright (c) 2002-3 Open Source Development Labs * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de> * Copyright (c) 2007 Novell Inc. * * This file is released under the GPLv2 * */ #include <linux/device.h> #include <linux/module.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/string.h> #include <linux/mutex.h> #include <linux/sysfs.h> #include "base.h" #include "power/power.h" /* /sys/devices/system */ static struct kset *system_kset; #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) /* * sysfs bindings for drivers */ #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) static int __must_check bus_rescan_devices_helper(struct device *dev, void *data); static struct bus_type *bus_get(struct bus_type *bus) { if (bus) { kset_get(&bus->p->subsys); return bus; } return NULL; } static void bus_put(struct bus_type *bus) { if (bus) kset_put(&bus->p->subsys); } static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct driver_attribute *drv_attr = to_drv_attr(attr); struct driver_private *drv_priv = to_driver(kobj); ssize_t ret = -EIO; if (drv_attr->show) ret = drv_attr->show(drv_priv->driver, buf); return ret; } static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) { struct driver_attribute *drv_attr = to_drv_attr(attr); struct driver_private *drv_priv = to_driver(kobj); ssize_t ret = -EIO; if (drv_attr->store) ret = drv_attr->store(drv_priv->driver, buf, count); return ret; } static const struct sysfs_ops driver_sysfs_ops = { .show = drv_attr_show, .store = drv_attr_store, }; static void driver_release(struct kobject *kobj) { struct driver_private *drv_priv = to_driver(kobj); pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); kfree(drv_priv); } static struct kobj_type driver_ktype = { .sysfs_ops = &driver_sysfs_ops, .release = driver_release, }; /* * sysfs bindings for buses */ static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct bus_attribute *bus_attr = to_bus_attr(attr); struct subsys_private *subsys_priv = to_subsys_private(kobj); ssize_t ret = 0; if (bus_attr->show) ret = bus_attr->show(subsys_priv->bus, buf); return ret; } static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) { struct bus_attribute *bus_attr = to_bus_attr(attr); struct subsys_private *subsys_priv = to_subsys_private(kobj); ssize_t ret = 0; if (bus_attr->store) ret = bus_attr->store(subsys_priv->bus, buf, count); return ret; } static const struct sysfs_ops bus_sysfs_ops = { .show = bus_attr_show, .store = bus_attr_store, }; int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) { int error; if (bus_get(bus)) { error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); bus_put(bus); } else error = -EINVAL; return error; } EXPORT_SYMBOL_GPL(bus_create_file); void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) { if (bus_get(bus)) { sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); bus_put(bus); } } EXPORT_SYMBOL_GPL(bus_remove_file); static struct kobj_type bus_ktype = { .sysfs_ops = &bus_sysfs_ops, }; static int bus_uevent_filter(struct kset *kset, struct kobject *kobj) { struct kobj_type *ktype = get_ktype(kobj); if (ktype == &bus_ktype) return 1; return 0; } static const struct kset_uevent_ops bus_uevent_ops = { .filter = bus_uevent_filter, }; static struct kset *bus_kset; /* Manually detach a device from its associated driver. */ static ssize_t unbind_store(struct device_driver *drv, const char *buf, size_t count) { struct bus_type *bus = bus_get(drv->bus); struct device *dev; int err = -ENODEV; dev = bus_find_device_by_name(bus, NULL, buf); if (dev && dev->driver == drv) { if (dev->parent) /* Needed for USB */ device_lock(dev->parent); device_release_driver(dev); if (dev->parent) device_unlock(dev->parent); err = count; } put_device(dev); bus_put(bus); return err; } static DRIVER_ATTR_WO(unbind); /* * Manually attach a device to a driver. * Note: the driver must want to bind to the device, * it is not possible to override the driver's id table. */ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t count) { struct bus_type *bus = bus_get(drv->bus); struct device *dev; int err = -ENODEV; dev = bus_find_device_by_name(bus, NULL, buf); if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { if (dev->parent) /* Needed for USB */ device_lock(dev->parent); device_lock(dev); err = driver_probe_device(drv, dev); device_unlock(dev); if (dev->parent) device_unlock(dev->parent); if (err > 0) { /* success */ err = count; } else if (err == 0) { /* driver didn't accept device */ err = -ENODEV; } } put_device(dev); bus_put(bus); return err; } static DRIVER_ATTR_WO(bind); static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf) { return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); } static ssize_t store_drivers_autoprobe(struct bus_type *bus, const char *buf, size_t count) { if (buf[0] == '0') bus->p->drivers_autoprobe = 0; else bus->p->drivers_autoprobe = 1; return count; } static ssize_t store_drivers_probe(struct bus_type *bus, const char *buf, size_t count) { struct device *dev; dev = bus_find_device_by_name(bus, NULL, buf); if (!dev) return -ENODEV; if (bus_rescan_devices_helper(dev, NULL) != 0) return -EINVAL; return count; } static struct device *next_device(struct klist_iter *i) { struct klist_node *n = klist_next(i); struct device *dev = NULL; struct device_private *dev_prv; if (n) { dev_prv = to_device_private_bus(n); dev = dev_prv->device; } return dev; } /** * bus_for_each_dev - device iterator. * @bus: bus type. * @start: device to start iterating from. * @data: data for the callback. * @fn: function to be called for each device. * * Iterate over @bus's list of devices, and call @fn for each, * passing it @data. If @start is not NULL, we use that device to * begin iterating from. * * We check the return of @fn each time. If it returns anything * other than 0, we break out and return that value. * * NOTE: The device that returns a non-zero value is not retained * in any way, nor is its refcount incremented. If the caller needs * to retain this data, it should do so, and increment the reference * count in the supplied callback. */ int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data, int (*fn)(struct device *, void *)) { struct klist_iter i; struct device *dev; int error = 0; if (!bus || !bus->p) return -EINVAL; klist_iter_init_node(&bus->p->klist_devices, &i, (start ? &start->p->knode_bus : NULL)); while ((dev = next_device(&i)) && !error) error = fn(dev, data); klist_iter_exit(&i); return error; } EXPORT_SYMBOL_GPL(bus_for_each_dev); /** * bus_find_device - device iterator for locating a particular device. * @bus: bus type * @start: Device to begin with * @data: Data to pass to match function * @match: Callback function to check device * * This is similar to the bus_for_each_dev() 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, this function will * return to the caller and not iterate over any more devices. */ struct device *bus_find_device(struct bus_type *bus, struct device *start, void *data, int (*match)(struct device *dev, void *data)) { struct klist_iter i; struct device *dev; if (!bus || !bus->p) return NULL; klist_iter_init_node(&bus->p->klist_devices, &i, (start ? &start->p->knode_bus : NULL)); while ((dev = next_device(&i))) if (match(dev, data) && get_device(dev)) break; klist_iter_exit(&i); return dev; } EXPORT_SYMBOL_GPL(bus_find_device); static int match_name(struct device *dev, void *data) { const char *name = data; return sysfs_streq(name, dev_name(dev)); } /** * bus_find_device_by_name - device iterator for locating a particular device of a specific name * @bus: bus type * @start: Device to begin with * @name: name of the device to match * * This is similar to the bus_find_device() function above, but it handles * searching by a name automatically, no need to write another strcmp matching * function. */ struct device *bus_find_device_by_name(struct bus_type *bus, struct device *start, const char *name) { return bus_find_device(bus, start, (void *)name, match_name); } EXPORT_SYMBOL_GPL(bus_find_device_by_name); /** * subsys_find_device_by_id - find a device with a specific enumeration number * @subsys: subsystem * @id: index 'id' in struct device * @hint: device to check first * * Check the hint's next object and if it is a match return it directly, * otherwise, fall back to a full list search. Either way a reference for * the returned object is taken. */ struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id, struct device *hint) { struct klist_iter i; struct device *dev; if (!subsys) return NULL; if (hint) { klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus); dev = next_device(&i); if (dev && dev->id == id && get_device(dev)) { klist_iter_exit(&i); return dev; } klist_iter_exit(&i); } klist_iter_init_node(&subsys->p->klist_devices, &i, NULL); while ((dev = next_device(&i))) { if (dev->id == id && get_device(dev)) { klist_iter_exit(&i); return dev; } } klist_iter_exit(&i); return NULL; } EXPORT_SYMBOL_GPL(subsys_find_device_by_id); static struct device_driver *next_driver(struct klist_iter *i) { struct klist_node *n = klist_next(i); struct driver_private *drv_priv; if (n) { drv_priv = container_of(n, struct driver_private, knode_bus); return drv_priv->driver; } return NULL; } /** * bus_for_each_drv - driver iterator * @bus: bus we're dealing with. * @start: driver to start iterating on. * @data: data to pass to the callback. * @fn: function to call for each driver. * * This is nearly identical to the device iterator above. * We iterate over each driver that belongs to @bus, and call * @fn for each. If @fn returns anything but 0, we break out * and return it. If @start is not NULL, we use it as the head * of the list. * * NOTE: we don't return the driver that returns a non-zero * value, nor do we leave the reference count incremented for that * driver. If the caller needs to know that info, it must set it * in the callback. It must also be sure to increment the refcount * so it doesn't disappear before returning to the caller. */ int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, void *data, int (*fn)(struct device_driver *, void *)) { struct klist_iter i; struct device_driver *drv; int error = 0; if (!bus) return -EINVAL; klist_iter_init_node(&bus->p->klist_drivers, &i, start ? &start->p->knode_bus : NULL); while ((drv = next_driver(&i)) && !error) error = fn(drv, data); klist_iter_exit(&i); return error; } EXPORT_SYMBOL_GPL(bus_for_each_drv); static int device_add_attrs(struct bus_type *bus, struct device *dev) { int error = 0; int i; if (!bus->dev_attrs) return 0; for (i = 0; bus->dev_attrs[i].attr.name; i++) { error = device_create_file(dev, &bus->dev_attrs[i]); if (error) { while (--i >= 0) device_remove_file(dev, &bus->dev_attrs[i]); break; } } return error; } static void device_remove_attrs(struct bus_type *bus, struct device *dev) { int i; if (bus->dev_attrs) { for (i = 0; bus->dev_attrs[i].attr.name; i++) device_remove_file(dev, &bus->dev_attrs[i]); } } /** * bus_add_device - add device to bus * @dev: device being added * * - Add device's bus attributes. * - Create links to device's bus. * - Add the device to its bus's list of devices. */ int bus_add_device(struct device *dev) { struct bus_type *bus = bus_get(dev->bus); int error = 0; if (bus) { pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); error = device_add_attrs(bus, dev);