uas-ugv/main/sx127x_driver/sx127x_driver.c

#include "sx127x_driver.h"

#include <string.h>
#include <freertos/task.h>
#include <esp_log.h>

const char *SX127X_TAG = "sx127x";

#define SX127X_CHECK(check, str, ret_val, ...)                                       \
    if (!(check))                                                                    \
    {                                                                                \
        ESP_LOGE(SX127X_TAG, "%s(%d): " str, __FUNCTION__, __LINE__, ##__VA_ARGS__); \
        return (ret_val);                                                            \
    }

#ifdef NODEBUG
#define SX127X_ERROR_CHECK(ret, fun)   \
    {                                  \
        esp_err_t _error_code = (ret); \
        if (_error_code != ESP_OK)     \
        {                              \
            return _error_code;        \
        }                              \
    }
#else
#define SX127X_ERROR_CHECK(ret, fun)                                    \
    {                                                                   \
        esp_err_t _error_code = (ret);                                  \
        if (_error_code != ESP_OK)                                      \
        {                                                               \
            const char *_error_name = esp_err_to_name(_error_code);     \
            ESP_LOGE(SX127X_TAG, "%s(%d): " fun ": %s (%d)",            \
                     __FUNCTION__, __LINE__, _error_name, _error_code); \
            return _error_code;                                         \
        }                                                               \
    }
#endif

esp_err_t sx127x_init(sx127x_config_t *config, sx127x_t *handle)
{
    esp_err_t ret;

    memcpy(&handle->config, config, sizeof(sx127x_config_t));

    ret = gpio_set_direction(config->rst_io_num, GPIO_MODE_OUTPUT);
    SX127X_ERROR_CHECK(ret, "gpio_set_direction")
    ret = gpio_set_direction(config->irq_io_num, GPIO_MODE_OUTPUT);
    SX127X_ERROR_CHECK(ret, "gpio_set_direction")

    gpio_set_level(config->cs_io_num, 1);

    // perform reset
    gpio_set_level(config->rst_io_num, 0);
    vTaskDelay(pdMS_TO_TICKS(10));
    gpio_set_level(config->rst_io_num, 1);
    vTaskDelay(pdMS_TO_TICKS(10));

    spi_bus_config_t bus_config = {
        .mosi_io_num = config->mosi_io_num,
        .miso_io_num = config->miso_io_num,
        .sclk_io_num = config->sck_io_num,
        .quadhd_io_num = -1,
        .quadwp_io_num = -1,
        .max_transfer_sz = SX127X_MAX_TRANSFER};
    ret = spi_bus_initialize(config->spi_host, &bus_config, 1);
    SX127X_ERROR_CHECK(ret, "spi_bus_initialize")

    spi_device_interface_config_t device_config = {
        .command_bits = 0,
        .address_bits = 8,
        .dummy_bits = 0,
        .mode = 0,
        .duty_cycle_pos = 0,
        .cs_ena_pretrans = 2,
        .cs_ena_posttrans = 2,
        .clock_speed_hz = 8, // 80mhz / 8 = 10mhz
        .input_delay_ns = 0,
        .spics_io_num = config->cs_io_num,
        .flags = 0,
        .queue_size = 8,
        .pre_cb = NULL,
        .post_cb = NULL,
    };
    ret = spi_bus_add_device(config->spi_host, &device_config, &handle->device_handle);
    SX127X_ERROR_CHECK(ret, "spi_bus_add_device")

    return ESP_OK;
}

esp_err_t sx127x_free(sx127x_t *handle)
{
    esp_err_t ret;

    ret = spi_bus_remove_device(handle->device_handle);
    SX127X_ERROR_CHECK(ret, "spi_bus_remove_device")

    ret = spi_bus_free(handle->config.spi_host);
    SX127X_ERROR_CHECK(ret, "spi_bus_free")

    return ESP_OK;
}