circuitpython/nrf5/hal/hal_spi.c

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/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Glenn Ruben Bakke
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdint.h>
#include <stdio.h>
#include "mphalport.h"
#include "hal_spi.h"
#ifdef HAL_SPI_MODULE_ENABLED
static uint32_t m_ss_pin;
static const uint32_t hal_spi_frequency_lookup[] = {
SPI_FREQUENCY_FREQUENCY_K125, // 125 kbps
SPI_FREQUENCY_FREQUENCY_K250, // 250 kbps
SPI_FREQUENCY_FREQUENCY_K500, // 500 kbps
SPI_FREQUENCY_FREQUENCY_M1, // 1 Mbps
SPI_FREQUENCY_FREQUENCY_M2, // 2 Mbps
SPI_FREQUENCY_FREQUENCY_M4, // 4 Mbps
SPI_FREQUENCY_FREQUENCY_M8 // 8 Mbps
};
void hal_spi_master_init(NRF_SPI_Type * p_instance, hal_spi_init_t const * p_spi_init) {
hal_gpio_pin_set(p_spi_init->enable_pin);
m_ss_pin = p_spi_init->enable_pin;
hal_gpio_cfg_pin_output(p_spi_init->clk_pin);
hal_gpio_cfg_pin_output(p_spi_init->mosi_pin);
hal_gpio_cfg_pin_input(p_spi_init->miso_pin, HAL_GPIO_PULL_DISABLED);
hal_gpio_cfg_pin_output(p_spi_init->enable_pin);
#if NRF51
p_instance->PSELSCK = p_spi_init->clk_pin;
p_instance->PSELMOSI = p_spi_init->mosi_pin;
p_instance->PSELMISO = p_spi_init->miso_pin;
#else
p_instance->PSEL.SCK = p_spi_init->clk_pin;
p_instance->PSEL.MOSI = p_spi_init->mosi_pin;
p_instance->PSEL.MISO = p_spi_init->miso_pin;
#endif
p_instance->FREQUENCY = hal_spi_frequency_lookup[p_spi_init->freq];
uint32_t mode;
switch (p_spi_init->mode) {
case HAL_SPI_MODE_CPOL0_CPHA0:
mode = (SPI_CONFIG_CPHA_Leading << SPI_CONFIG_CPHA_Pos) | (SPI_CONFIG_CPOL_ActiveHigh << SPI_CONFIG_CPOL_Pos);
break;
case HAL_SPI_MODE_CPOL0_CPHA1:
mode = (SPI_CONFIG_CPHA_Trailing << SPI_CONFIG_CPHA_Pos) | (SPI_CONFIG_CPOL_ActiveHigh << SPI_CONFIG_CPOL_Pos);
break;
case HAL_SPI_MODE_CPOL1_CPHA0:
mode = (SPI_CONFIG_CPHA_Leading << SPI_CONFIG_CPHA_Pos) | (SPI_CONFIG_CPOL_ActiveLow << SPI_CONFIG_CPOL_Pos);
break;
case HAL_SPI_MODE_CPOL1_CPHA1:
mode = (SPI_CONFIG_CPHA_Trailing << SPI_CONFIG_CPHA_Pos) | (SPI_CONFIG_CPOL_ActiveLow << SPI_CONFIG_CPOL_Pos);
break;
default:
mode = 0;
break;
}
if (p_spi_init->lsb_first) {
p_instance->CONFIG = (mode | (SPI_CONFIG_ORDER_LsbFirst << SPI_CONFIG_ORDER_Pos));
} else {
p_instance->CONFIG = (mode | (SPI_CONFIG_ORDER_MsbFirst << SPI_CONFIG_ORDER_Pos));
}
p_instance->EVENTS_READY = 0U;
p_instance->ENABLE = (SPI_ENABLE_ENABLE_Enabled << SPI_ENABLE_ENABLE_Pos);
}
void hal_spi_master_tx_rx(NRF_SPI_Type * p_instance, uint16_t transfer_size, const uint8_t * tx_data, uint8_t * rx_data) {
uint16_t number_of_txd_bytes = 0;
p_instance->EVENTS_READY = 0;
hal_gpio_pin_clear(m_ss_pin);
while (number_of_txd_bytes < transfer_size) {
p_instance->TXD = (uint32_t)(tx_data[number_of_txd_bytes]);
// wait for the transaction complete or timeout (about 10ms - 20 ms)
while (p_instance->EVENTS_READY == 0) {
;
}
p_instance->EVENTS_READY = 0;
rx_data[number_of_txd_bytes] = (uint8_t)p_instance->RXD;
number_of_txd_bytes++;
};
hal_gpio_pin_set(m_ss_pin);
}
#endif // HAL_SPI_MODULE_ENABLED