diff options
Diffstat (limited to 'drivers/base/dd.c')
| -rw-r--r-- | drivers/base/dd.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 3b419c9a1e7e..2b905016664d 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -65,7 +65,8 @@ void device_bind_driver(struct device * dev) * This function returns 1 if a match is found, an error if one * occurs (that is not -ENODEV or -ENXIO), and 0 otherwise. * - * This function must be called with @dev->sem held. + * This function must be called with @dev->sem held. When called + * for a USB interface, @dev->parent->sem must be held as well. */ int driver_probe_device(struct device_driver * drv, struct device * dev) { @@ -123,6 +124,8 @@ static int __device_attach(struct device_driver * drv, void * data) * * Returns 1 if the device was bound to a driver; * 0 if no matching device was found; error code otherwise. + * + * When called for a USB interface, @dev->parent->sem must be held. */ int device_attach(struct device * dev) { @@ -152,10 +155,14 @@ static int __driver_attach(struct device * dev, void * data) * is an error. */ + if (dev->parent) /* Needed for USB */ + down(&dev->parent->sem); down(&dev->sem); if (!dev->driver) driver_probe_device(drv, dev); up(&dev->sem); + if (dev->parent) + up(&dev->parent->sem); return 0; } @@ -181,6 +188,8 @@ void driver_attach(struct device_driver * drv) * Manually detach device from driver. * * __device_release_driver() must be called with @dev->sem held. + * When called for a USB interface, @dev->parent->sem must be held + * as well. */ static void __device_release_driver(struct device * dev) @@ -233,10 +242,14 @@ void driver_detach(struct device_driver * drv) get_device(dev); spin_unlock(&drv->klist_devices.k_lock); + if (dev->parent) /* Needed for USB */ + down(&dev->parent->sem); down(&dev->sem); if (dev->driver == drv) __device_release_driver(dev); up(&dev->sem); + if (dev->parent) + up(&dev->parent->sem); put_device(dev); } } |