Linux Kernel  3.7.1
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Data Fields
spi_master Struct Reference

#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_structkworker_task
struct kthread_work pump_messages
spinlock_t queue_lock
struct list_head queue
struct spi_messagecur_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.

Field Documentation

bool bus_lock_flag

Definition at line 309 of file spi.h.

struct mutex bus_lock_mutex

Definition at line 306 of file spi.h.

spinlock_t bus_lock_spinlock

Definition at line 305 of file spi.h.

s16 bus_num

Definition at line 283 of file spi.h.

bool busy

Definition at line 357 of file spi.h.

void(* cleanup)(struct spi_device *spi)

Definition at line 342 of file spi.h.

struct spi_message* cur_msg

Definition at line 356 of file spi.h.

Definition at line 273 of file spi.h.

u16 dma_alignment

Definition at line 293 of file spi.h.

u16 flags

Definition at line 299 of file spi.h.

Definition at line 351 of file spi.h.

struct task_struct* kworker_task

Definition at line 352 of file spi.h.

Definition at line 275 of file spi.h.

u16 mode_bits

Definition at line 296 of file spi.h.

u16 num_chipselect

Definition at line 288 of file spi.h.

int(* prepare_transfer_hardware)(struct spi_master *master)

Definition at line 361 of file spi.h.

struct kthread_work pump_messages

Definition at line 353 of file spi.h.

Definition at line 355 of file spi.h.

spinlock_t queue_lock

Definition at line 354 of file spi.h.

bool queued

Definition at line 350 of file spi.h.

bool rt

Definition at line 359 of file spi.h.

bool running

Definition at line 358 of file spi.h.

Definition at line 317 of file spi.h.

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

Definition at line 338 of file spi.h.

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

Definition at line 362 of file spi.h.

int(* unprepare_transfer_hardware)(struct spi_master *master)

Definition at line 364 of file spi.h.

The documentation for this struct was generated from the following file: