diff options
Diffstat (limited to 'drivers/base/base.h')
| -rw-r--r-- | drivers/base/base.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/base/base.h b/drivers/base/base.h index 0042e4774b0c..123031a757d9 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -73,6 +73,7 @@ static inline void subsys_put(struct subsys_private *sp) kset_put(&sp->subsys); } +struct subsys_private *bus_to_subsys(const struct bus_type *bus); struct subsys_private *class_to_subsys(const struct class *class); struct driver_private { @@ -180,6 +181,22 @@ int driver_add_groups(const struct device_driver *drv, const struct attribute_gr void driver_remove_groups(const struct device_driver *drv, const struct attribute_group **groups); void device_driver_detach(struct device *dev); +static inline void device_set_driver(struct device *dev, const struct device_driver *drv) +{ + /* + * Majority (all?) read accesses to dev->driver happens either + * while holding device lock or in bus/driver code that is only + * invoked when the device is bound to a driver and there is no + * concern of the pointer being changed while it is being read. + * However when reading device's uevent file we read driver pointer + * without taking device lock (so we do not block there for + * arbitrary amount of time). We use WRITE_ONCE() here to prevent + * tearing so that READ_ONCE() can safely be used in uevent code. + */ + // FIXME - this cast should not be needed "soon" + WRITE_ONCE(dev->driver, (struct device_driver *)drv); +} + int devres_release_all(struct device *dev); void device_block_probing(void); void device_unblock_probing(void); |