Serial Peripheral Interface (SPI) Driver

Serial Peripheral Interface (SPI) bus driver support. More...

Modules
	Linux SPI User-Space API
	RTEMS port of Linux SPI user-space API.

Files
file	spi.h
	Serial Peripheral Interface (SPI) Driver API.

Data Structures
struct	spi_bus
	SPI bus control. More...

Macros
#define	SPI_BUS_OBTAIN   _IO(SPI_IOC_MAGIC, 13)
	Obtains the bus. More...
#define	SPI_BUS_RELEASE   _IO(SPI_IOC_MAGIC, 23)
	Releases the bus. More...

Functions
int	spi_bus_init (spi_bus *bus)
	Initializes a bus control. More...
spi_bus *	spi_bus_alloc_and_init (size_t size)
	Allocates a bus control from the heap and initializes it. More...
void	spi_bus_destroy (spi_bus *bus)
	Destroys a bus control. More...
void	spi_bus_destroy_and_free (spi_bus *bus)
	Destroys a bus control and frees its memory. More...
int	spi_bus_register (spi_bus *bus, const char *bus_path)
	Registers a bus control. More...

Detailed Description

Serial Peripheral Interface (SPI) bus driver support.

Macro Definition Documentation

SPI_BUS_OBTAIN

#define SPI_BUS_OBTAIN   _IO(SPI_IOC_MAGIC, 13)

Obtains the bus.

This command has no argument.

SPI_BUS_RELEASE

#define SPI_BUS_RELEASE   _IO(SPI_IOC_MAGIC, 23)

Releases the bus.

This command has no argument.

Function Documentation

spi_bus_alloc_and_init()

spi_bus* spi_bus_alloc_and_init

(

size_t

size

)

Allocates a bus control from the heap and initializes it.

After a sucessful allocation and initialization the bus control must be destroyed via spi_bus_destroy_and_free(). A registered bus control will be automatically destroyed in case the device file is unlinked. Make sure to call spi_bus_destroy_and_free() in a custom destruction handler.

Parameters

[in]

size

The size of the bus control. This enables the addition of bus controller specific data to the base bus control. The bus control is zero initialized.

Return values

non-NULL	The new bus control.
NULL	An error occurred. The errno is set to indicate the error.

See also

spi_bus_register()

spi_bus_destroy()

void spi_bus_destroy

(

spi_bus *

bus

)

Destroys a bus control.

Parameters

[in]

bus

The bus control.

spi_bus_destroy_and_free()

void spi_bus_destroy_and_free

(

spi_bus *

bus

)

Destroys a bus control and frees its memory.

Parameters

[in]

bus

The bus control.

spi_bus_init()

int spi_bus_init

(

spi_bus *

bus

)

Initializes a bus control.

After a sucessful initialization the bus control must be destroyed via spi_bus_destroy(). A registered bus control will be automatically destroyed in case the device file is unlinked. Make sure to call spi_bus_destroy() in a custom destruction handler.

Parameters

[in]

bus

The bus control.

Return values

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also

spi_bus_register()

spi_bus_register()

int spi_bus_register	(	spi_bus *	bus,
		const char *	bus_path
	)

Registers a bus control.

This function claims ownership of the bus control regardless if the registration is successful or not.

Parameters

[in]	bus	The bus control.
[in]	bus_path	The path to the bus device file.

Return values

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.