SPI interface. More...

#include <ipxe/nvs.h>

Data Structures
struct	spi_device
	An SPI device. More...

struct	spi_bus
	An SPI bus. More...

Macros
#define	SPI_WRSR 0x01
	Write status register. More...

#define	SPI_WRITE 0x02
	Write data to memory array. More...

#define	SPI_READ 0x03
	Read data from memory array. More...

#define	SPI_WRDI 0x04
	Reset write enable latch. More...

#define	SPI_RDSR 0x05
	Read status register. More...

#define	SPI_WREN 0x06
	Set write enable latch. More...

#define	ATMEL_SECTOR_ERASE 0x52
	Erase one sector in memory array (Not supported on all devices) More...

#define	ATMEL_CHIP_ERASE 0x62
	Erase all sections in memory array (Not supported on all devices) More...

#define	ATMEL_RDID 0x15
	Read manufacturer and product ID (Not supported on all devices) More...

#define	SPI_STATUS_WPEN 0x80
	Write-protect pin enabled. More...

#define	SPI_STATUS_BP2 0x10
	Block protection bit 2. More...

#define	SPI_STATUS_BP1 0x08
	Block protection bit 1. More...

#define	SPI_STATUS_BP0 0x04
	Block protection bit 0. More...

#define	SPI_STATUS_WEN 0x02
	State of the write enable latch. More...

#define	SPI_STATUS_NRDY 0x01
	Device busy flag. More...

#define	SPI_AUTODETECT_ADDRESS_LEN 0
	SPI magic autodetection address length. More...

#define	SPI_MODE_CPHA 0x01
	Clock phase (CPHA) mode bit. More...

#define	SPI_MODE_CPOL 0x02
	Clock polarity (CPOL) mode bit. More...

#define	SPI_MODE_SSPOL 0x10
	Slave select polarity mode bit. More...

#define	SPI_MODE_MICROWIRE 1
	Microwire-compatible mode. More...

#define	SPI_MODE_MICROWIRE_PLUS 0
	Microwire/Plus-compatible mode. More...

#define	SPI_MODE_THREEWIRE ( SPI_MODE_MICROWIRE_PLUS \| SPI_MODE_SSPOL )
	Threewire-compatible mode. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)

static	__attribute__ ((always_inline)) void init_at25f1024(struct spi_device *device)
	Atmel AT25F1024 serial flash. More...

int	spi_read (struct nvs_device nvs, unsigned int address, void data, size_t len)
	Read data from SPI device. More...

int	spi_write (struct nvs_device nvs, unsigned int address, const void data, size_t len)
	Write data to SPI device. More...

Detailed Description

SPI interface.

Definition in file spi.h.

Macro Definition Documentation

◆ SPI_AUTODETECT_ADDRESS_LEN

#define SPI_AUTODETECT_ADDRESS_LEN 0

SPI magic autodetection address length.

Set spi_device::address_len to SPI_AUTODETECT_ADDRESS_LEN if the address length should be autodetected.

Definition at line 113 of file spi.h.

◆ SPI_MODE_CPHA

#define SPI_MODE_CPHA 0x01

Clock phase (CPHA) mode bit.

Phase 0 is sample on rising edge, shift data on falling edge.

Phase 1 is shift data on rising edge, sample data on falling edge.

Definition at line 163 of file spi.h.

◆ SPI_MODE_CPOL

#define SPI_MODE_CPOL 0x02

Clock polarity (CPOL) mode bit.

This bit reflects the idle state of the clock line (SCLK).

Definition at line 169 of file spi.h.

◆ SPI_MODE_SSPOL

#define SPI_MODE_SSPOL 0x10

Slave select polarity mode bit.

This bit reflects that active state of the slave select lines. It is not part of the normal SPI mode number (which covers only SPI_MODE_CPOL and SPI_MODE_CPHA), but is included here for convenience.

Definition at line 178 of file spi.h.

◆ SPI_MODE_MICROWIRE

#define SPI_MODE_MICROWIRE 1

Microwire-compatible mode.

This is SPI mode 1 (i.e. CPOL=0, CPHA=1), and is compatible with the original Microwire protocol.

Definition at line 185 of file spi.h.

◆ SPI_MODE_MICROWIRE_PLUS

#define SPI_MODE_MICROWIRE_PLUS 0

Microwire/Plus-compatible mode.

This is SPI mode 0 (i.e. CPOL=0, CPHA=0), and is compatible with the Microwire/Plus protocol

Definition at line 192 of file spi.h.

◆ SPI_MODE_THREEWIRE

#define SPI_MODE_THREEWIRE ( SPI_MODE_MICROWIRE_PLUS | SPI_MODE_SSPOL )

Threewire-compatible mode.

This mode is compatible with Atmel's series of "three-wire" interfaces.

Definition at line 199 of file spi.h.

Function Documentation

◆ FILE_LICENCE()

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )

◆ spi_read()

int spi_read	(	struct nvs_device *	nvs,
		unsigned int	address,
		void *	data,
		size_t	len
	)

Read data from SPI device.

Parameters

nvs	NVS device
address	Address from which to read
data	Data buffer
len	Length of data buffer

Return values

rc	Return status code

Definition at line 89 of file spi.c.

                                         {
         struct spi_device *device = nvs_to_spi ( nvs );
         struct spi_bus *bus = device->bus;
         unsigned int command = spi_command ( SPI_READ, address,
                                              device->munge_address );
         int rc;
 
         DBG ( "SPI %p reading %zd bytes from %#04x\n", device, len, address );
         if ( ( rc = bus->rw ( bus, device, command, address,
                               NULL, data, len ) ) != 0 ) {
                 DBG ( "SPI %p failed to read data from device\n", device );
                 return rc;
         }
 
         return 0;
 }

References address, bus, data, DBG, len, NULL, spi_device::nvs, rc, spi_command(), and SPI_READ.

◆ spi_write()

int spi_write	(	struct nvs_device *	nvs,
		unsigned int	address,
		const void *	data,
		size_t	len
	)

Write data to SPI device.