Add minimal bus locking API which is useful for serial devices that implement request-reply protocol
Cc: [email protected] Cc: Guenter Roeck <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Andrey Smirnov <[email protected]> --- drivers/tty/serdev/core.c | 1 + include/linux/serdev.h | 11 +++++++++++ 2 files changed, 12 insertions(+) diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c index 759e834..20ca231 100644 --- a/drivers/tty/serdev/core.c +++ b/drivers/tty/serdev/core.c @@ -269,6 +269,7 @@ struct serdev_device *serdev_device_alloc(struct serdev_controller *ctrl) serdev->dev.type = &serdev_device_type; init_completion(&serdev->write_wakeup); mutex_init(&serdev->write_lock); + mutex_init(&serdev->bus_lock); return serdev; } EXPORT_SYMBOL_GPL(serdev_device_alloc); diff --git a/include/linux/serdev.h b/include/linux/serdev.h index 8f7aa35..6b73a79 100644 --- a/include/linux/serdev.h +++ b/include/linux/serdev.h @@ -48,6 +48,7 @@ struct serdev_device { const struct serdev_device_ops *ops; struct completion write_wakeup; struct mutex write_lock; + struct mutex bus_lock; }; static inline struct serdev_device *to_serdev_device(struct device *d) @@ -55,6 +56,16 @@ static inline struct serdev_device *to_serdev_device(struct device *d) return container_of(d, struct serdev_device, dev); } +static inline void serdev_device_bus_lock(struct serdev_device *serdev) +{ + mutex_lock(&serdev->bus_lock); +} + +static inline void serdev_device_bus_unlock(struct serdev_device *serdev) +{ + mutex_unlock(&serdev->bus_lock); +} + /** * struct serdev_device_driver - serdev slave device driver * @driver: serdev device drivers should initialize name field of this -- 2.9.3
