Merge branch 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/linvil...
[pandora-kernel.git] / drivers / base / bus.c
index 2e954d0..7d8a7ce 100644 (file)
@@ -371,12 +371,31 @@ 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_put;
+               error = sysfs_create_link(&bus->devices.kobj,
+                                               &dev->kobj, dev->bus_id);
+               if (error)
+                       goto out_id;
+               error = sysfs_create_link(&dev->kobj,
+                               &dev->bus->subsys.kset.kobj, "subsystem");
+               if (error)
+                       goto out_subsys;
+               error = sysfs_create_link(&dev->kobj,
+                               &dev->bus->subsys.kset.kobj, "bus");
+               if (error)
+                       goto out_deprecated;
        }
+       return 0;
+
+out_deprecated:
+       sysfs_remove_link(&dev->kobj, "subsystem");
+out_subsys:
+       sysfs_remove_link(&bus->devices.kobj, dev->bus_id);
+out_id:
+       device_remove_attrs(bus, dev);
+out_put:
+       put_bus(dev->bus);
        return error;
 }
 
@@ -384,16 +403,24 @@ 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 +439,10 @@ 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);
+               if (dev->is_registered) {
+                       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 +485,17 @@ 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 +504,7 @@ 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
 
@@ -476,35 +513,49 @@ 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;
 
-       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;
-               }
-               drv->kobj.kset = &bus->drivers;
-               if ((error = kobject_register(&drv->kobj))) {
-                       put_bus(bus);
-                       return error;
-               }
-
-               driver_attach(drv);
-               klist_add_tail(&drv->knode_bus, &bus->klist_drivers);
-               module_add_driver(drv->owner, drv);
-
-               driver_add_attrs(bus, drv);
-               add_bind_files(drv);
+       if (!bus)
+               return 0;
+
+       pr_debug("bus %s: add driver %s\n", bus->name, drv->name);
+       error = kobject_set_name(&drv->kobj, "%s", drv->name);
+       if (error)
+               goto out_put_bus;
+       drv->kobj.kset = &bus->drivers;
+       if ((error = kobject_register(&drv->kobj)))
+               goto out_put_bus;
+
+       error = driver_attach(drv);
+       if (error)
+               goto out_unregister;
+       klist_add_tail(&drv->knode_bus, &bus->klist_drivers);
+       module_add_driver(drv->owner, 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.
@@ -516,30 +567,36 @@ int bus_add_driver(struct device_driver * drv)
 
 void bus_remove_driver(struct device_driver * drv)
 {
-       if (drv->bus) {
-               remove_bind_files(drv);
-               driver_remove_attrs(drv->bus, drv);
-               klist_remove(&drv->knode_bus);
-               pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name);
-               driver_detach(drv);
-               module_remove_driver(drv);
-               kobject_unregister(&drv->kobj);
-               put_bus(drv->bus);
-       }
+       if (!drv->bus)
+               return;
+
+       remove_bind_files(drv);
+       driver_remove_attrs(drv->bus, drv);
+       klist_remove(&drv->knode_bus);
+       pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name);
+       driver_detach(drv);
+       module_remove_driver(drv);
+       kobject_unregister(&drv->kobj);
+       put_bus(drv->bus);
 }
 
 
 /* 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 +607,9 @@ 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 +621,7 @@ 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 +630,14 @@ 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 +712,6 @@ 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.
@@ -706,12 +747,16 @@ 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);
-       bus_add_attrs(bus);
+       klist_init(&bus->klist_drivers, NULL, NULL);
+       retval = bus_add_attrs(bus);
+       if (retval)
+               goto bus_attrs_fail;
 
        pr_debug("bus type '%s' registered\n", bus->name);
        return 0;
 
+bus_attrs_fail:
+       kset_unregister(&bus->drivers);
 bus_drivers_fail:
        kset_unregister(&bus->devices);
 bus_devices_fail: