diff options
Diffstat (limited to 'drivers/staging/meilhaus/meslock.h')
-rw-r--r-- | drivers/staging/meilhaus/meslock.h | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/drivers/staging/meilhaus/meslock.h b/drivers/staging/meilhaus/meslock.h new file mode 100644 index 0000000..f42b25c --- /dev/null +++ b/drivers/staging/meilhaus/meslock.h @@ -0,0 +1,73 @@ +/** + * @file meslock.h + * + * @brief Provides the subdevice lock class. + * @note Copyright (C) 2006 Meilhaus Electronic GmbH (support@meilhaus.de) + * @author Guenter Gebhardt + */ + +#ifndef _MESLOCK_H_ +#define _MESLOCK_H_ + +#include <linux/spinlock.h> + +#ifdef __KERNEL__ + +/** + * @brief The subdevice lock class. + */ +typedef struct me_slock { + struct file *filep; /**< Pointer to file structure holding the subdevice. */ + int count; /**< Number of tasks which are inside the subdevice. */ + spinlock_t spin_lock; /**< Spin lock protecting the attributes from concurrent access. */ +} me_slock_t; + +/** + * @brief Tries to enter a subdevice. + * + * @param slock The subdevice lock instance. + * @param filep The file structure identifying the calling process. + * + * @return 0 on success. + */ +int me_slock_enter(struct me_slock *slock, struct file *filep); + +/** + * @brief Exits a subdevice. + * + * @param slock The subdevice lock instance. + * @param filep The file structure identifying the calling process. + * + * @return 0 on success. + */ +int me_slock_exit(struct me_slock *slock, struct file *filep); + +/** + * @brief Tries to perform a locking action on a subdevice. + * + * @param slock The subdevice lock instance. + * @param filep The file structure identifying the calling process. + * @param The action to be done. + * + * @return 0 on success. + */ +int me_slock_lock(struct me_slock *slock, struct file *filep, int lock); + +/** + * @brief Initializes a lock structure. + * + * @param slock The lock structure to initialize. + * @return 0 on success. + */ +int me_slock_init(me_slock_t * slock); + +/** + * @brief Deinitializes a lock structure. + * + * @param slock The lock structure to deinitialize. + * @return 0 on success. + */ +void me_slock_deinit(me_slock_t * slock); + +#endif +#endif |