diff options
Diffstat (limited to 'drivers/base/bus.c')
| -rw-r--r-- | drivers/base/bus.c | 41 |
1 files changed, 36 insertions, 5 deletions
diff --git a/drivers/base/bus.c b/drivers/base/bus.c index fa601b085eb..29f6af554e7 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -152,7 +152,11 @@ static ssize_t driver_unbind(struct device_driver *drv, dev = bus_find_device(bus, NULL, (void *)buf, driver_helper); if (dev && dev->driver == drv) { + if (dev->parent) /* Needed for USB */ + down(&dev->parent->sem); device_release_driver(dev); + if (dev->parent) + up(&dev->parent->sem); err = count; } put_device(dev); @@ -175,9 +179,13 @@ static ssize_t driver_bind(struct device_driver *drv, dev = bus_find_device(bus, NULL, (void *)buf, driver_helper); if (dev && dev->driver == NULL) { + if (dev->parent) /* Needed for USB */ + down(&dev->parent->sem); down(&dev->sem); err = driver_probe_device(drv, dev); up(&dev->sem); + if (dev->parent) + up(&dev->parent->sem); } put_device(dev); put_bus(bus); @@ -420,6 +428,26 @@ static void driver_remove_attrs(struct bus_type * bus, struct device_driver * dr } } +#ifdef CONFIG_HOTPLUG +/* + * 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) +{ + driver_create_file(drv, &driver_attr_unbind); + driver_create_file(drv, &driver_attr_bind); +} + +static void remove_bind_files(struct device_driver *drv) +{ + driver_remove_file(drv, &driver_attr_bind); + driver_remove_file(drv, &driver_attr_unbind); +} +#else +static inline void add_bind_files(struct device_driver *drv) {} +static inline void remove_bind_files(struct device_driver *drv) {} +#endif /** * bus_add_driver - Add a driver to the bus. @@ -449,8 +477,7 @@ int bus_add_driver(struct device_driver * drv) module_add_driver(drv->owner, drv); driver_add_attrs(bus, drv); - driver_create_file(drv, &driver_attr_unbind); - driver_create_file(drv, &driver_attr_bind); + add_bind_files(drv); } return error; } @@ -468,8 +495,7 @@ int bus_add_driver(struct device_driver * drv) void bus_remove_driver(struct device_driver * drv) { if (drv->bus) { - driver_remove_file(drv, &driver_attr_bind); - driver_remove_file(drv, &driver_attr_unbind); + 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); @@ -484,8 +510,13 @@ 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) { - if (!dev->driver) + if (!dev->driver) { + if (dev->parent) /* Needed for USB */ + down(&dev->parent->sem); device_attach(dev); + if (dev->parent) + up(&dev->parent->sem); + } return 0; } |