esp-idf/components/driver/include/driver/spi_common.h

145 lines
6.7 KiB
C

// Copyright 2010-2019 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once
#include <stdint.h>
#include <stdbool.h>
#include "esp_err.h"
#include "esp32/rom/lldesc.h"
#include "soc/spi_periph.h"
#include "hal/spi_types.h"
#include "sdkconfig.h"
#ifdef __cplusplus
extern "C"
{
#endif
//Maximum amount of bytes that can be put in one DMA descriptor
#define SPI_MAX_DMA_LEN (4096-4)
/**
* Transform unsigned integer of length <= 32 bits to the format which can be
* sent by the SPI driver directly.
*
* E.g. to send 9 bits of data, you can:
*
* uint16_t data = SPI_SWAP_DATA_TX(0x145, 9);
*
* Then points tx_buffer to ``&data``.
*
* @param DATA Data to be sent, can be uint8_t, uint16_t or uint32_t.
* @param LEN Length of data to be sent, since the SPI peripheral sends from
* the MSB, this helps to shift the data to the MSB.
*/
#define SPI_SWAP_DATA_TX(DATA, LEN) __builtin_bswap32((uint32_t)(DATA)<<(32-(LEN)))
/**
* Transform received data of length <= 32 bits to the format of an unsigned integer.
*
* E.g. to transform the data of 15 bits placed in a 4-byte array to integer:
*
* uint16_t data = SPI_SWAP_DATA_RX(*(uint32_t*)t->rx_data, 15);
*
* @param DATA Data to be rearranged, can be uint8_t, uint16_t or uint32_t.
* @param LEN Length of data received, since the SPI peripheral writes from
* the MSB, this helps to shift the data to the LSB.
*/
#define SPI_SWAP_DATA_RX(DATA, LEN) (__builtin_bswap32(DATA)>>(32-(LEN)))
#define SPICOMMON_BUSFLAG_SLAVE 0 ///< Initialize I/O in slave mode
#define SPICOMMON_BUSFLAG_MASTER (1<<0) ///< Initialize I/O in master mode
#define SPICOMMON_BUSFLAG_IOMUX_PINS (1<<1) ///< Check using iomux pins. Or indicates the pins are configured through the IO mux rather than GPIO matrix.
#define SPICOMMON_BUSFLAG_SCLK (1<<2) ///< Check existing of SCLK pin. Or indicates CLK line initialized.
#define SPICOMMON_BUSFLAG_MISO (1<<3) ///< Check existing of MISO pin. Or indicates MISO line initialized.
#define SPICOMMON_BUSFLAG_MOSI (1<<4) ///< Check existing of MOSI pin. Or indicates CLK line initialized.
#define SPICOMMON_BUSFLAG_DUAL (1<<5) ///< Check MOSI and MISO pins can output. Or indicates bus able to work under DIO mode.
#define SPICOMMON_BUSFLAG_WPHD (1<<6) ///< Check existing of WP and HD pins. Or indicates WP & HD pins initialized.
#define SPICOMMON_BUSFLAG_QUAD (SPICOMMON_BUSFLAG_DUAL|SPICOMMON_BUSFLAG_WPHD) ///< Check existing of MOSI/MISO/WP/HD pins as output. Or indicates bus able to work under QIO mode.
#define SPICOMMON_BUSFLAG_NATIVE_PINS SPICOMMON_BUSFLAG_IOMUX_PINS
/**
* @brief This is a configuration structure for a SPI bus.
*
* You can use this structure to specify the GPIO pins of the bus. Normally, the driver will use the
* GPIO matrix to route the signals. An exception is made when all signals either can be routed through
* the IO_MUX or are -1. In that case, the IO_MUX is used, allowing for >40MHz speeds.
*
* @note Be advised that the slave driver does not use the quadwp/quadhd lines and fields in spi_bus_config_t refering to these lines will be ignored and can thus safely be left uninitialized.
*/
typedef struct {
int mosi_io_num; ///< GPIO pin for Master Out Slave In (=spi_d) signal, or -1 if not used.
int miso_io_num; ///< GPIO pin for Master In Slave Out (=spi_q) signal, or -1 if not used.
int sclk_io_num; ///< GPIO pin for Spi CLocK signal, or -1 if not used.
int quadwp_io_num; ///< GPIO pin for WP (Write Protect) signal which is used as D2 in 4-bit communication modes, or -1 if not used.
int quadhd_io_num; ///< GPIO pin for HD (HolD) signal which is used as D3 in 4-bit communication modes, or -1 if not used.
int max_transfer_sz; ///< Maximum transfer size, in bytes. Defaults to 4094 if 0.
uint32_t flags; ///< Abilities of bus to be checked by the driver. Or-ed value of ``SPICOMMON_BUSFLAG_*`` flags.
int intr_flags; /**< Interrupt flag for the bus to set the priority, and IRAM attribute, see
* ``esp_intr_alloc.h``. Note that the EDGE, INTRDISABLED attribute are ignored
* by the driver. Note that if ESP_INTR_FLAG_IRAM is set, ALL the callbacks of
* the driver, and their callee functions, should be put in the IRAM.
*/
} spi_bus_config_t;
/**
* @brief Initialize a SPI bus
*
* @warning For now, only supports HSPI and VSPI.
*
* @param host SPI peripheral that controls this bus
* @param bus_config Pointer to a spi_bus_config_t struct specifying how the host should be initialized
* @param dma_chan Either channel 1 or 2, or 0 in the case when no DMA is required. Selecting a DMA channel
* for a SPI bus allows transfers on the bus to have sizes only limited by the amount of
* internal memory. Selecting no DMA channel (by passing the value 0) limits the amount of
* bytes transfered to a maximum of 64. Set to 0 if only the SPI flash uses
* this bus.
*
* @warning If a DMA channel is selected, any transmit and receive buffer used should be allocated in
* DMA-capable memory.
*
* @warning The ISR of SPI is always executed on the core which calls this
* function. Never starve the ISR on this core or the SPI transactions will not
* be handled.
*
* @return
* - ESP_ERR_INVALID_ARG if configuration is invalid
* - ESP_ERR_INVALID_STATE if host already is in use
* - ESP_ERR_NO_MEM if out of memory
* - ESP_OK on success
*/
esp_err_t spi_bus_initialize(spi_host_device_t host, const spi_bus_config_t *bus_config, int dma_chan);
/**
* @brief Free a SPI bus
*
* @warning In order for this to succeed, all devices have to be removed first.
*
* @param host SPI peripheral to free
* @return
* - ESP_ERR_INVALID_ARG if parameter is invalid
* - ESP_ERR_INVALID_STATE if not all devices on the bus are freed
* - ESP_OK on success
*/
esp_err_t spi_bus_free(spi_host_device_t host);
#ifdef __cplusplus
}
#endif