1 /**
2  * \file
3  *
4  * \brief SAM True Random Number Generator (TRNG) Driver
5  *
6  * Copyright (C) 2014-2015 Atmel Corporation. All rights reserved.
7  *
8  * \asf_license_start
9  *
10  * \page License
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions are met:
14  *
15  * 1. Redistributions of source code must retain the above copyright notice,
16  *    this list of conditions and the following disclaimer.
17  *
18  * 2. Redistributions in binary form must reproduce the above copyright notice,
19  *    this list of conditions and the following disclaimer in the documentation
20  *    and/or other materials provided with the distribution.
21  *
22  * 3. The name of Atmel may not be used to endorse or promote products derived
23  *    from this software without specific prior written permission.
24  *
25  * 4. This software may only be redistributed and used in connection with an
26  *    Atmel microcontroller product.
27  *
28  * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
29  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
30  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
31  * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
32  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
36  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
37  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38  * POSSIBILITY OF SUCH DAMAGE.
39  *
40  * \asf_license_stop
41  *
42  */
43 /*
44  * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
45  */
46 
47 #ifndef TRNG_CALLBACK_H_INCLUDED
48 #define TRNG_CALLBACK_H_INCLUDED
49 
50 #ifdef __cplusplus
51 extern "C" {
52 #endif
53 
54 /**
55  * \addtogroup asfdoc_sam0_trng_group
56  *
57  * @{
58  */
59 
60 #include <trng.h>
61 
62 /**
63  * Enum for the possible types of TRNG asynchronous jobs that may be issued to
64  * the driver.
65  */
66 enum trng_job_type {
67 	/** Asynchronous TRNG read into a user provided buffer */
68 	TRNG_JOB_READ_BUFFER,
69 };
70 
71 /**
72  * \name Callback Management
73  * @{
74  */
75 enum status_code trng_register_callback(
76 		struct trng_module *const module,
77 		trng_callback_t callback_func,
78 		enum trng_callback callback_type);
79 
80 enum status_code trng_unregister_callback(
81 		struct trng_module *module,
82 		enum trng_callback callback_type);
83 
84 /**
85  * \brief Enables callback
86  *
87  * Enables the callback function registered by \ref
88  * trng_register_callback. The callback function will be called from the
89  * interrupt handler when the conditions for the callback type are met.
90  *
91  * \param[in]     module        Pointer to TRNG software instance struct
92  * \param[in]     callback_type Callback type given by an enum
93  */
trng_enable_callback(struct trng_module * const module,enum trng_callback callback_type)94 static inline void trng_enable_callback(
95 		struct trng_module *const module,
96 		enum trng_callback callback_type)
97 {
98 	/* Sanity check arguments */
99 	Assert(module);
100 
101 	/* Enable callback */
102 	module->enable_callback_mask |= (1 << callback_type);
103 }
104 
105 /**
106  * \brief Disables callback
107  *
108  * Disables the callback function registered by the \ref
109  * trng_register_callback.
110  *
111  * \param[in]     module        Pointer to TRNG software instance struct
112  * \param[in]     callback_type Callback type given by an enum
113  */
trng_disable_callback(struct trng_module * const module,enum trng_callback callback_type)114 static inline void trng_disable_callback(
115 		struct trng_module *const module,
116 		enum trng_callback callback_type)
117 {
118 	/* Sanity check arguments */
119 	Assert(module);
120 
121 	/* Disable callback */
122 	module->enable_callback_mask &= ~(1UL << callback_type);
123 
124 	/* Disable data ready interrupt */
125 	if (callback_type == TRNG_CALLBACK_READ_BUFFER) {
126 		module->hw->INTENCLR.reg = TRNG_INTENCLR_DATARDY;
127 	}
128 }
129 
130 /** @} */
131 
132 /**
133  * \name Job Management
134  * @{
135  */
136 enum status_code trng_read_buffer_job(
137 		struct trng_module *const module_inst,
138 		uint32_t *buffer,
139 		uint32_t number);
140 
141 enum status_code trng_get_job_status(
142 		struct trng_module *module_inst,
143 		enum trng_job_type type);
144 
145 void trng_abort_job(
146 		struct trng_module *module_inst,
147 		enum trng_job_type type);
148 
149 /** @} */
150 
151 /** @} */
152 
153 #ifdef __cplusplus
154 }
155 #endif
156 
157 #endif /* TRNG_CALLBACK_H_INCLUDED */
158 
159