1 /**
2  * @file
3  * @brief    Exclusive access lock utility functions.
4 */
5 
6 /* ****************************************************************************
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37  * $Date: 2018-08-09 18:45:02 -0500 (Thu, 09 Aug 2018) $
38  * $Revision: 36818 $
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40  *************************************************************************** */
41 
42 /* Define to prevent redundant inclusion */
43 #ifndef _MXC_LOCK_H_
44 #define _MXC_LOCK_H_
45 
46 /* **** Includes **** */
47 #include "mxc_config.h"
48 
49 #ifdef __cplusplus
50 extern "C" {
51 #endif
52 
53 /**
54  * @ingroup    syscfg
55  * @defgroup   mxc_lock_utilities Exclusive Access Locks
56  * @brief      Lock functions to obtain and release a variable for exclusive
57  *             access. These functions are marked interrupt safe if they are
58  *             interrupt safe.
59  * @{
60  */
61 
62 /* **** Definitions **** */
63 
64 /* **** Globals **** */
65 
66 /* **** Function Prototypes **** */
67 
68 /**
69  * @brief      Attempts to acquire the lock.
70  * @details    This in an interrupt safe function that can be used as a mutex.
71  *             The lock variable must remain in scope until the lock is
72  *             released. Will not block if another thread has already acquired
73  *             the lock.
74  * @param      lock   Pointer to variable that is used for the lock.
75  * @param      value  Value to be place in the lock. Can not be 0.
76  *
77  * @return     #E_NO_ERROR if everything successful, #E_BUSY if lock is taken.
78  */
79 int mxc_get_lock(uint32_t *lock, uint32_t value);
80 
81 /**
82  * @brief         Free the given lock.
83  * @param[in,out] lock  Pointer to the variable used for the lock. When the lock
84  *                      is free, the value pointed to by @p lock is set to zero.
85  */
86 void mxc_free_lock(uint32_t *lock);
87 
88 /**@} end of group mxc_lock_utilities */
89 
90 #ifdef __cplusplus
91 }
92 #endif
93 
94 #endif /* _MXC_LOCK_H_ */
95