#include "hw_config.h"

/* SDIO Interface */
static sd_sdio_if_t sdio_if = {
    /*
    Pins CLK_gpio, D1_gpio, D2_gpio, and D3_gpio are at offsets from pin
    D0_gpio. The offsets are determined by sd_driver\SDIO\rp2040_sdio.pio.
        CLK_gpio = (D0_gpio + SDIO_CLK_PIN_D0_OFFSET) % 32;
        As of this writing, SDIO_CLK_PIN_D0_OFFSET is 30,
            which is -2 in mod32 arithmetic, so:
        CLK_gpio = D0_gpio -2.
        D1_gpio = D0_gpio + 1;
        D2_gpio = D0_gpio + 2;
        D3_gpio = D0_gpio + 3;
    */
    .CMD_gpio = 3,
    .D0_gpio = 4,
    .baud_rate = 125 * 1000 * 1000 / 6  // 20833333 Hz
};

/* Hardware Configuration of the SD Card socket "object" */
static sd_card_t sd_card = {.type = SD_IF_SDIO, .sdio_if_p = &sdio_if};

/**
 * @brief Get the number of SD cards.
 *
 * @return The number of SD cards, which is 1 in this case.
 */
size_t sd_get_num() { return 1; }

/**
 * @brief Get a pointer to an SD card object by its number.
 *
 * @param[in] num The number of the SD card to get.
 *
 * @return A pointer to the SD card object, or @c NULL if the number is invalid.
 */
sd_card_t* sd_get_by_num(size_t num) {
  if (0 == num) {
    // The number 0 is a valid SD card number.
    // Return a pointer to the sd_card object.
    return &sd_card;
  } else {
    // The number is invalid. Return @c NULL.
    return NULL;
  }
}