diff options
Diffstat (limited to 'drivers/base/bus.c')
-rw-r--r-- | drivers/base/bus.c | 133 |
1 files changed, 79 insertions, 54 deletions
diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 2e954d07175a..12173d16bea7 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -371,12 +371,20 @@ int bus_add_device(struct device * dev) if (bus) { pr_debug("bus %s: add device %s\n", bus->name, dev->bus_id); error = device_add_attrs(bus, dev); - if (!error) { - sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id); - sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "subsystem"); - sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "bus"); - } + if (error) + goto out; + error = sysfs_create_link(&bus->devices.kobj, + &dev->kobj, dev->bus_id); + if (error) + goto out; + error = sysfs_create_link(&dev->kobj, + &dev->bus->subsys.kset.kobj, "subsystem"); + if (error) + goto out; + error = sysfs_create_link(&dev->kobj, + &dev->bus->subsys.kset.kobj, "bus"); } +out: return error; } @@ -384,16 +392,24 @@ int bus_add_device(struct device * dev) * bus_attach_device - add device to bus * @dev: device tried to attach to a driver * + * - Add device to bus's list of devices. * - Try to attach to driver. */ -void bus_attach_device(struct device * dev) +int bus_attach_device(struct device * dev) { - struct bus_type * bus = dev->bus; + struct bus_type *bus = dev->bus; + int ret = 0; if (bus) { - device_attach(dev); - klist_add_tail(&dev->knode_bus, &bus->klist_devices); + dev->is_registered = 1; + ret = device_attach(dev); + if (ret >= 0) { + klist_add_tail(&dev->knode_bus, &bus->klist_devices); + ret = 0; + } else + dev->is_registered = 0; } + return ret; } /** @@ -412,7 +428,8 @@ void bus_remove_device(struct device * dev) sysfs_remove_link(&dev->kobj, "bus"); sysfs_remove_link(&dev->bus->devices.kobj, dev->bus_id); device_remove_attrs(dev->bus, dev); - klist_remove(&dev->knode_bus); + dev->is_registered = 0; + klist_del(&dev->knode_bus); pr_debug("bus %s: remove device %s\n", dev->bus->name, dev->bus_id); device_release_driver(dev); put_bus(dev->bus); @@ -455,10 +472,17 @@ static void driver_remove_attrs(struct bus_type * bus, struct device_driver * dr * Thanks to drivers making their tables __devinit, we can't allow manual * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled. */ -static void add_bind_files(struct device_driver *drv) +static int __must_check add_bind_files(struct device_driver *drv) { - driver_create_file(drv, &driver_attr_unbind); - driver_create_file(drv, &driver_attr_bind); + int ret; + + ret = driver_create_file(drv, &driver_attr_unbind); + if (ret == 0) { + ret = driver_create_file(drv, &driver_attr_bind); + if (ret) + driver_remove_file(drv, &driver_attr_unbind); + } + return ret; } static void remove_bind_files(struct device_driver *drv) @@ -467,7 +491,7 @@ static void remove_bind_files(struct device_driver *drv) driver_remove_file(drv, &driver_attr_unbind); } #else -static inline void add_bind_files(struct device_driver *drv) {} +static inline int add_bind_files(struct device_driver *drv) { return 0; } static inline void remove_bind_files(struct device_driver *drv) {} #endif @@ -476,7 +500,7 @@ static inline void remove_bind_files(struct device_driver *drv) {} * @drv: driver. * */ -int bus_add_driver(struct device_driver * drv) +int bus_add_driver(struct device_driver *drv) { struct bus_type * bus = get_bus(drv->bus); int error = 0; @@ -484,27 +508,39 @@ int bus_add_driver(struct device_driver * drv) if (bus) { pr_debug("bus %s: add driver %s\n", bus->name, drv->name); error = kobject_set_name(&drv->kobj, "%s", drv->name); - if (error) { - put_bus(bus); - return error; - } + if (error) + goto out_put_bus; drv->kobj.kset = &bus->drivers; - if ((error = kobject_register(&drv->kobj))) { - put_bus(bus); - return error; - } + if ((error = kobject_register(&drv->kobj))) + goto out_put_bus; - driver_attach(drv); + error = driver_attach(drv); + if (error) + goto out_unregister; klist_add_tail(&drv->knode_bus, &bus->klist_drivers); module_add_driver(drv->owner, drv); - driver_add_attrs(bus, drv); - add_bind_files(drv); + error = driver_add_attrs(bus, drv); + if (error) { + /* How the hell do we get out of this pickle? Give up */ + printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", + __FUNCTION__, drv->name); + } + error = add_bind_files(drv); + if (error) { + /* Ditto */ + printk(KERN_ERR "%s: add_bind_files(%s) failed\n", + __FUNCTION__, drv->name); + } } return error; +out_unregister: + kobject_unregister(&drv->kobj); +out_put_bus: + put_bus(bus); + return error; } - /** * bus_remove_driver - delete driver from bus's knowledge. * @drv: driver. @@ -530,16 +566,21 @@ void bus_remove_driver(struct device_driver * drv) /* Helper for bus_rescan_devices's iter */ -static int bus_rescan_devices_helper(struct device *dev, void *data) +static int __must_check bus_rescan_devices_helper(struct device *dev, + void *data) { + int ret = 0; + if (!dev->driver) { if (dev->parent) /* Needed for USB */ down(&dev->parent->sem); - device_attach(dev); + ret = device_attach(dev); if (dev->parent) up(&dev->parent->sem); + if (ret > 0) + ret = 0; } - return 0; + return ret < 0 ? ret : 0; } /** @@ -550,9 +591,9 @@ static int bus_rescan_devices_helper(struct device *dev, void *data) * attached and rescan it against existing drivers to see if it matches * any by calling device_attach() for the unbound devices. */ -void bus_rescan_devices(struct bus_type * bus) +int bus_rescan_devices(struct bus_type * bus) { - bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); + return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); } /** @@ -564,7 +605,7 @@ void bus_rescan_devices(struct bus_type * bus) * to use if probing criteria changed during a devices lifetime and * driver attachment should change accordingly. */ -void device_reprobe(struct device *dev) +int device_reprobe(struct device *dev) { if (dev->driver) { if (dev->parent) /* Needed for USB */ @@ -573,14 +614,14 @@ void device_reprobe(struct device *dev) if (dev->parent) up(&dev->parent->sem); } - - bus_rescan_devices_helper(dev, NULL); + return bus_rescan_devices_helper(dev, NULL); } EXPORT_SYMBOL_GPL(device_reprobe); -struct bus_type * get_bus(struct bus_type * bus) +struct bus_type *get_bus(struct bus_type *bus) { - return bus ? container_of(subsys_get(&bus->subsys), struct bus_type, subsys) : NULL; + return bus ? container_of(subsys_get(&bus->subsys), + struct bus_type, subsys) : NULL; } void put_bus(struct bus_type * bus) @@ -655,22 +696,6 @@ static void klist_devices_put(struct klist_node *n) put_device(dev); } -static void klist_drivers_get(struct klist_node *n) -{ - struct device_driver *drv = container_of(n, struct device_driver, - knode_bus); - - get_driver(drv); -} - -static void klist_drivers_put(struct klist_node *n) -{ - struct device_driver *drv = container_of(n, struct device_driver, - knode_bus); - - put_driver(drv); -} - /** * bus_register - register a bus with the system. * @bus: bus. @@ -706,7 +731,7 @@ int bus_register(struct bus_type * bus) goto bus_drivers_fail; klist_init(&bus->klist_devices, klist_devices_get, klist_devices_put); - klist_init(&bus->klist_drivers, klist_drivers_get, klist_drivers_put); + klist_init(&bus->klist_drivers, NULL, NULL); bus_add_attrs(bus); pr_debug("bus type '%s' registered\n", bus->name); |