1 /*
2 * Copyright (c) 2016 - 2020, Nordic Semiconductor ASA
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this
9 * list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * 3. Neither the name of the copyright holder nor the names of its
16 * contributors may be used to endorse or promote products derived from this
17 * software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
20 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
23 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <nrfx.h>
33
34 #if NRFX_CHECK(NRFX_RNG_ENABLED)
35
36 #include <nrfx_rng.h>
37
38 #define NRFX_LOG_MODULE RNG
39 #include <nrfx_log.h>
40
41 /**
42 * @brief Internal state of RNG driver.
43 */
44 static nrfx_drv_state_t m_rng_state;
45
46 /**
47 * @brief Pointer to handler calling from interrupt routine.
48 */
49 static nrfx_rng_evt_handler_t m_rng_hndl;
50
nrfx_rng_init(nrfx_rng_config_t const * p_config,nrfx_rng_evt_handler_t handler)51 nrfx_err_t nrfx_rng_init(nrfx_rng_config_t const * p_config, nrfx_rng_evt_handler_t handler)
52 {
53 NRFX_ASSERT(p_config);
54 NRFX_ASSERT(handler);
55 if (m_rng_state != NRFX_DRV_STATE_UNINITIALIZED)
56 {
57 return NRFX_ERROR_ALREADY_INITIALIZED;
58 }
59
60 m_rng_hndl = handler;
61
62 if (p_config->error_correction)
63 {
64 nrf_rng_error_correction_enable(NRF_RNG);
65 }
66 nrf_rng_shorts_disable(NRF_RNG, NRF_RNG_SHORT_VALRDY_STOP_MASK);
67 NRFX_IRQ_PRIORITY_SET(RNG_IRQn, p_config->interrupt_priority);
68 NRFX_IRQ_ENABLE(RNG_IRQn);
69
70 m_rng_state = NRFX_DRV_STATE_INITIALIZED;
71
72 return NRFX_SUCCESS;
73 }
74
nrfx_rng_start(void)75 void nrfx_rng_start(void)
76 {
77 NRFX_ASSERT(m_rng_state == NRFX_DRV_STATE_INITIALIZED);
78 nrf_rng_event_clear(NRF_RNG, NRF_RNG_EVENT_VALRDY);
79 nrf_rng_int_enable(NRF_RNG, NRF_RNG_INT_VALRDY_MASK);
80 nrf_rng_task_trigger(NRF_RNG, NRF_RNG_TASK_START);
81 }
82
nrfx_rng_stop(void)83 void nrfx_rng_stop(void)
84 {
85 NRFX_ASSERT(m_rng_state == NRFX_DRV_STATE_INITIALIZED);
86 nrf_rng_int_disable(NRF_RNG, NRF_RNG_INT_VALRDY_MASK);
87 nrf_rng_task_trigger(NRF_RNG, NRF_RNG_TASK_STOP);
88 }
89
nrfx_rng_uninit(void)90 void nrfx_rng_uninit(void)
91 {
92 NRFX_ASSERT(m_rng_state == NRFX_DRV_STATE_INITIALIZED);
93
94 nrf_rng_int_disable(NRF_RNG, NRF_RNG_INT_VALRDY_MASK);
95 nrf_rng_task_trigger(NRF_RNG, NRF_RNG_TASK_STOP);
96 NRFX_IRQ_DISABLE(RNG_IRQn);
97
98 m_rng_state = NRFX_DRV_STATE_UNINITIALIZED;
99 NRFX_LOG_INFO("Uninitialized.");
100 }
101
nrfx_rng_irq_handler(void)102 void nrfx_rng_irq_handler(void)
103 {
104 nrf_rng_event_clear(NRF_RNG, NRF_RNG_EVENT_VALRDY);
105
106 uint8_t rng_value = nrf_rng_random_value_get(NRF_RNG);
107
108 m_rng_hndl(rng_value);
109
110 NRFX_LOG_DEBUG("Event: NRF_RNG_EVENT_VALRDY.");
111 }
112
113 #endif // NRFX_CHECK(NRFX_RNG_ENABLED)
114