circuitpython/nrf5/hal/hal_twie.c

/*
 * This file is part of the Micro Python project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2017 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 "mphalport.h"
#include "hal_twi.h"

#ifdef HAL_TWIE_MODULE_ENABLED

// EasyDMA variants
#define TWI_MASTER_BASE(x) ((NRF_TWIM_Type *)TWI_BASE_POINTERS[x])
#define TWI_SLAVE_BASE(x) ((NRF_TWIS_Type *)TWI_BASE_POINTERS[x])

static const uint32_t hal_twi_frequency_lookup[] = {
    TWIM_FREQUENCY_FREQUENCY_K100, // 100 kbps
    TWIM_FREQUENCY_FREQUENCY_K250, // 250 kbps
    TWIM_FREQUENCY_FREQUENCY_K400, // 400 kbps
};

void hal_twi_master_init(NRF_TWI_Type * p_instance, hal_twi_init_t const * p_twi_init) {
    // cast to master type
    NRF_TWIM_Type * twim_instance = (NRF_TWIM_Type *)p_instance;

    twim_instance->PSEL.SCL  = p_twi_init->scl_pin->pin;
    twim_instance->PSEL.SDA  = p_twi_init->sda_pin->pin;

#if NRF52840_XXAA
    twim_instance->PSEL.SCL |= (p_twi_init->scl_pin->port << TWIM_PSEL_SCL_PORT_Pos);
    twim_instance->PSEL.SDA |= (p_twi_init->sda_pin->port << TWIM_PSEL_SDA_PORT_Pos);
#endif
    twim_instance->FREQUENCY = hal_twi_frequency_lookup[p_twi_init->freq];
    twim_instance->ENABLE    = (TWIM_ENABLE_ENABLE_Enabled << TWIM_ENABLE_ENABLE_Pos);
}

#include <stdio.h>

void hal_twi_master_tx(NRF_TWI_Type  * p_instance,
                       uint8_t         addr,
                       uint16_t        transfer_size,
                       const uint8_t * tx_data,
                       bool            stop) {
    // cast to master type
    NRF_TWIM_Type * twim_instance = (NRF_TWIM_Type *)p_instance;

    twim_instance->ADDRESS = addr;

    printf("Hal I2C transfer size: %u, addr: %x, stop: %u\n", transfer_size, addr, stop);
    twim_instance->TXD.MAXCNT     = transfer_size;
    twim_instance->TXD.PTR        = (uint32_t)tx_data;

    if (stop) {
        twim_instance->SHORTS = TWIM_SHORTS_LASTTX_STOP_Msk;
    } else {
        twim_instance->SHORTS = TWIM_SHORTS_LASTTX_SUSPEND_Msk;
    }

    if (twim_instance->EVENTS_SUSPENDED == 1) {
        printf("Resuming\n");
        twim_instance->EVENTS_SUSPENDED = 0;
        twim_instance->EVENTS_STOPPED   = 0;
        twim_instance->TASKS_RESUME     = 1; // in case of resume
    } else {
        printf("Starting\n");
        twim_instance->EVENTS_SUSPENDED = 0;
        twim_instance->EVENTS_STOPPED   = 0;
        twim_instance->TASKS_STARTTX    = 1;
    }

    printf("Going into loop\n");
    while (twim_instance->EVENTS_STOPPED == 0 && twim_instance->EVENTS_SUSPENDED == 0) {
        ;
    }
}

void hal_twi_master_rx(NRF_TWI_Type  * p_instance,
                       uint8_t         addr,
                       uint16_t        transfer_size,
                       const uint8_t * rx_data) {
    // cast to master type
    NRF_TWIM_Type * twim_instance = (NRF_TWIM_Type *)p_instance;

    twim_instance->ADDRESS = addr;

}

void hal_twi_slave_init(NRF_TWI_Type * p_instance, hal_twi_init_t const * p_twi_init) {
    // cast to slave type
    NRF_TWIS_Type * twis_instance = (NRF_TWIS_Type *)p_instance;
    (void)twis_instance;
}

#endif // HAL_TWIE_MODULE_ENABLED