#include <spi.h>

Data Fields
struct device	dev

struct list_head	list

s16	bus_num

u16	num_chipselect

u16	dma_alignment

u16	mode_bits

u16	flags

spinlock_t	bus_lock_spinlock

struct mutex	bus_lock_mutex

bool	bus_lock_flag

int(*	setup )(struct spi_device *spi)

int(*	transfer )(struct spi_device spi, struct spi_message mesg)

void(*	cleanup )(struct spi_device *spi)

bool	queued

struct kthread_worker	kworker

struct task_struct *	kworker_task

struct kthread_work	pump_messages

spinlock_t	queue_lock

struct list_head	queue

struct spi_message *	cur_msg

bool	busy

bool	running

bool	rt

int(*	prepare_transfer_hardware )(struct spi_master *master)

int(*	transfer_one_message )(struct spi_master master, struct spi_message mesg)

int(*	unprepare_transfer_hardware )(struct spi_master *master)

Detailed Description

struct spi_master - interface to SPI master controller : device interface to this driver : link with the global spi_master list : board-specific (and often SOC-specific) identifier for a given SPI controller. : chipselects are used to distinguish individual SPI slaves, and are numbered from zero to num_chipselects. each slave has a chipselect signal, but it's common that not every chipselect is connected to a slave. : SPI controller constraint on DMA buffers alignment. : flags understood by this controller driver : other constraints relevant to this driver : spinlock for SPI bus locking : mutex for SPI bus locking : indicates that the SPI bus is locked for exclusive use : updates the device mode and clocking records used by a device's SPI controller; protocol code may call this. This must fail if an unrecognized or unsupported mode is requested. It's always safe to call this unless transfers are pending on the device whose settings are being modified. : adds a message to the controller's transfer queue. : frees controller-specific state : whether this master is providing an internal message queue : thread struct for message pump : pointer to task for message pump kworker thread : work struct for scheduling work to the message pump : spinlock to syncronise access to message queue : message queue : the currently in-flight message : message pump is busy : message pump is running : whether this queue is set to run as a realtime task : a message will soon arrive from the queue so the subsystem requests the driver to prepare the transfer hardware by issuing this call : the subsystem calls the driver to transfer a single message while queuing transfers that arrive in the meantime. When the driver is finished with this message, it must call spi_finalize_current_message() so the subsystem can issue the next transfer : there are currently no more messages on the queue so the subsystem notifies the driver that it may relax the hardware by issuing this call

Each SPI master controller can communicate with one or more children. These make a small bus, sharing MOSI, MISO and SCK signals but not chip select signals. Each device may be configured to use a different clock rate, since those shared signals are ignored unless the chip is selected.

The driver for an SPI controller manages access to those devices through a queue of spi_message transactions, copying data between CPU memory and an SPI slave device. For each such message it queues, it calls the message's completion function when the transaction completes.

Definition at line 272 of file spi.h.