1 /*
2 * Copyright (c) 2019 - 2025, Nordic Semiconductor ASA
3 * All rights reserved.
4 *
5 * SPDX-License-Identifier: BSD-3-Clause
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright notice, this
11 * list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the copyright holder nor the names of its
18 * contributors may be used to endorse or promote products derived from this
19 * software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 */
33
34 #include <nrfx_twi_twim.h>
35
36 #if NRFX_CHECK(NRFX_TWI_ENABLED) || NRFX_CHECK(NRFX_TWIM_ENABLED)
37
38 #include <hal/nrf_gpio.h>
39
40 #define TWI_TWIM_PIN_CONFIGURE(_pin) nrf_gpio_cfg((_pin), \
41 NRF_GPIO_PIN_DIR_OUTPUT, \
42 NRF_GPIO_PIN_INPUT_CONNECT, \
43 NRF_GPIO_PIN_PULLUP, \
44 NRF_GPIO_PIN_S0D1, \
45 NRF_GPIO_PIN_NOSENSE)
46
nrfx_twi_twim_bus_recover(uint32_t scl_pin,uint32_t sda_pin)47 nrfx_err_t nrfx_twi_twim_bus_recover(uint32_t scl_pin, uint32_t sda_pin)
48 {
49 nrf_gpio_pin_set(scl_pin);
50 nrf_gpio_pin_set(sda_pin);
51
52 TWI_TWIM_PIN_CONFIGURE(scl_pin);
53 TWI_TWIM_PIN_CONFIGURE(sda_pin);
54
55 #if NRF_GPIO_HAS_CLOCKPIN
56 #if defined(NRF_TWIM_CLOCKPIN_SCL_NEEDED)
57 nrf_gpio_pin_clock_set(scl_pin, true);
58 #endif
59 #if defined(NRF_TWIM_CLOCKPIN_SDA_NEEDED)
60 nrf_gpio_pin_clock_set(sda_pin, true);
61 #endif
62 #endif
63
64 NRFX_DELAY_US(4);
65
66 for (uint8_t i = 0; i < 9; i++)
67 {
68 if (nrf_gpio_pin_read(sda_pin))
69 {
70 break;
71 }
72 else
73 {
74 // Pulse CLOCK signal
75 nrf_gpio_pin_clear(scl_pin);
76 NRFX_DELAY_US(4);
77 nrf_gpio_pin_set(scl_pin);
78 NRFX_DELAY_US(4);
79 }
80 }
81
82 // Generate a STOP condition on the bus
83 nrf_gpio_pin_clear(sda_pin);
84 NRFX_DELAY_US(4);
85 nrf_gpio_pin_set(sda_pin);
86 NRFX_DELAY_US(4);
87
88 if (nrf_gpio_pin_read(sda_pin))
89 {
90 return NRFX_SUCCESS;
91 }
92 else
93 {
94 return NRFX_ERROR_INTERNAL;
95 }
96 }
97
98 #endif // NRFX_CHECK(NRFX_TWI_ENABLED) || NRFX_CHECK(NRFX_TWIM_ENABLED)
99
