esp-idf/components/driver/include/esp_private/spi_slave_internal.h

/*
 * SPDX-FileCopyrightText: 2020-2021 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */

/**
 * @brief
 * This file contains SPI Slave private/internal APIs. Private/Internal APIs are:
 * - Visible to other IDF components
 * - Suggest NOT to use these APIs in your applications
 * - We don't provide backward compatibility on these APIs either
 */

#pragma once
#include "sdkconfig.h"
#include "esp_err.h"
#include "hal/spi_types.h"
#include "driver/spi_slave.h"

#ifdef __cplusplus
extern "C" {
#endif


/**
 * @brief Reset the trans Queue of slave driver
 * @note
 * This API is used to reset SPI Slave transaction queue. After calling this function:
 * - The SPI Slave transaction queue will be reset.
 *
 * @note This API shouldn't be called when the corresponding SPI Master is doing an SPI transaction.
 * If this gets called when its corresponding SPI Master is doing an SPI transaction, the SPI Slave behaviour is undefined
 *
 * @param host SPI peripheral that is acting as a slave
 *
 * @return
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP_OK                on success
 */
esp_err_t spi_slave_queue_reset(spi_host_device_t host);


/**
 * @brief Reset the trans Queue from within ISR of slave driver
 * @note
 * This API is used to reset SPI Slave transaction queue from within ISR. After calling this function:
 * - The SPI Slave transaction queue will be empty.
 *
 * @param host SPI peripheral that is acting as a slave
 *
 * @return
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP_OK                on success
 */
esp_err_t spi_slave_queue_reset_isr(spi_host_device_t host);


/**
 * @brief Queue a SPI transaction in ISR
 * @note
 * Similar as ``spi_slave_queue_trans``, but can and can only called within an ISR, then get the transaction results
 * through the transaction descriptor passed in ``spi_slave_interface_config_t::post_trans_cb``. if use this API, you
 * should trigger a transaction by normal ``spi_slave_queue_trans`` once and only once to start isr
 *
 * If you use both ``spi_slave_queue_trans`` and ``spi_slave_queue_trans_isr`` simultaneously to transfer valid data,
 * you should deal with concurrency issues on your self risk
 *
 * @param host SPI peripheral that is acting as a slave
 * @param trans_desc Description of transaction to execute. Not const because we may want to write status back
 *                   into the transaction description.
 * @return
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP_ERR_NO_MEM        if trans_queue is full
 *         - ESP_OK                on success
 */
esp_err_t spi_slave_queue_trans_isr(spi_host_device_t host, const spi_slave_transaction_t *trans_desc);


#ifdef __cplusplus
}
#endif