spi.h File Reference

Low-level SPI peripheral driver interface definition. More...

Detailed Description

Low-level SPI peripheral driver interface definition.

Author

Hauke Petersen hauke.nosp@m..pet.nosp@m.ersen.nosp@m.@fu-.nosp@m.berli.nosp@m.n.de

Definition in file spi.h.

#include <endian.h>
#include <errno.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include "periph_cpu.h"
#include "periph_conf.h"
#include "periph/gpio.h"

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Data Structures
struct	spi_gpio_mode_t
	SPI gpio mode. More...

Macros
#define	CONFIG_SPI_DMA_THRESHOLD_BYTES   16
	Threshold under which polling transfers are used instead of DMA TODO: determine at run-time based on SPI clock.
#define	SPI_DEV(x)   (x)
	Default SPI device access macro.
#define	SPI_UNDEF   (UINT_FAST8_MAX)
	Define global value for undefined SPI device.
#define	SPI_CS_UNDEF   (GPIO_UNDEF)
	Define value for unused CS line.
#define	SPI_HWCS(x)   (SPI_CS_UNDEF)
	Default SPI hardware chip select access macro.

Typedefs
typedef uint_fast8_t	spi_t
	Default type for SPI devices.
typedef gpio_t	spi_cs_t
	Chip select pin type overlaps with gpio_t so it can be casted to this.

Enumerations
enum	{   SPI_OK = 0 , SPI_NODEV = -ENXIO , SPI_NOCS = -EINVAL , SPI_NOMODE = -EINVAL ,   SPI_NOCLK = -EINVAL }
	Status codes used by the SPI driver interface. More...
enum	spi_mode_t { SPI_MODE_0 = 0 , SPI_MODE_1 , SPI_MODE_2 , SPI_MODE_3 }
	Available SPI modes, defining the configuration of clock polarity and clock phase. More...
enum	spi_clk_t {   SPI_CLK_100KHZ = 0 , SPI_CLK_400KHZ , SPI_CLK_1MHZ , SPI_CLK_5MHZ ,   SPI_CLK_10MHZ }
	Available SPI clock speeds. More...

Functions
void	spi_init (spi_t bus)
	Basic initialization of the given SPI bus.
void	spi_init_pins (spi_t bus)
	Initialize the used SPI bus pins, i.e.
int	spi_init_cs (spi_t bus, spi_cs_t cs)
	Initialize the given chip select pin.
void	spi_deinit_pins (spi_t dev)
	Change the pins of the given SPI bus back to plain GPIO functionality.
gpio_t	spi_pin_miso (spi_t dev)
	Get the MISO pin of the given SPI bus.
gpio_t	spi_pin_mosi (spi_t dev)
	Get the MOSI pin of the given SPI bus.
gpio_t	spi_pin_clk (spi_t dev)
	Get the CLK pin of the given SPI bus.
int	spi_init_with_gpio_mode (spi_t bus, const spi_gpio_mode_t *mode)
	Initialize MOSI/MISO/SCLK pins with adapted GPIO modes.
void	spi_acquire (spi_t bus, spi_cs_t cs, spi_mode_t mode, spi_clk_t clk)
	Start a new SPI transaction.
void	spi_release (spi_t bus)
	Finish an ongoing SPI transaction by releasing the given SPI bus.
uint8_t	spi_transfer_byte (spi_t bus, spi_cs_t cs, bool cont, uint8_t out)
	Transfer one byte on the given SPI bus.
void	spi_transfer_bytes (spi_t bus, spi_cs_t cs, bool cont, const void *out, void *in, size_t len)
	Transfer a number bytes using the given SPI bus.
uint8_t	spi_transfer_reg (spi_t bus, spi_cs_t cs, uint8_t reg, uint8_t out)
	Transfer one byte to/from a given register address.
void	spi_transfer_regs (spi_t bus, spi_cs_t cs, uint8_t reg, const void *out, void *in, size_t len)
	Transfer a number of bytes to/from a given register address.
static uint16_t	spi_transfer_u16_be (spi_t bus, spi_cs_t cs, bool cont, uint16_t host_number)
	Transfer a 16 bit number in big endian byte order.