/* * Copyright (c) 2019 - 2020, Nordic Semiconductor ASA * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. Neither the name of the copyright holder nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include #if NRFX_CHECK(NRFX_TWI_ENABLED) || NRFX_CHECK(NRFX_TWIM_ENABLED) #include #define TWI_TWIM_PIN_CONFIGURE(_pin) nrf_gpio_cfg((_pin), \ NRF_GPIO_PIN_DIR_OUTPUT, \ NRF_GPIO_PIN_INPUT_CONNECT, \ NRF_GPIO_PIN_PULLUP, \ NRF_GPIO_PIN_S0D1, \ NRF_GPIO_PIN_NOSENSE) nrfx_err_t nrfx_twi_twim_bus_recover(uint32_t scl_pin, uint32_t sda_pin) { nrf_gpio_pin_set(scl_pin); nrf_gpio_pin_set(sda_pin); TWI_TWIM_PIN_CONFIGURE(scl_pin); TWI_TWIM_PIN_CONFIGURE(sda_pin); NRFX_DELAY_US(4); for (uint8_t i = 0; i < 9; i++) { if (nrf_gpio_pin_read(sda_pin)) { break; } else { // Pulse CLOCK signal nrf_gpio_pin_clear(scl_pin); NRFX_DELAY_US(4); nrf_gpio_pin_set(scl_pin); NRFX_DELAY_US(4); } } // Generate a STOP condition on the bus nrf_gpio_pin_clear(sda_pin); NRFX_DELAY_US(4); nrf_gpio_pin_set(sda_pin); NRFX_DELAY_US(4); if (nrf_gpio_pin_read(sda_pin)) { return NRFX_SUCCESS; } else { return NRFX_ERROR_INTERNAL; } } #endif // NRFX_CHECK(NRFX_TWI_ENABLED) || NRFX_CHECK(NRFX_TWIM_ENABLED)