STRUCT SPI_BOARD_INF(9) Serial Peripheral Interface (S STRUCT SPI_BOARD_INF(9)NAMEstruct_spi_board_info - board-specific template for a SPI device
SYNOPSIS
struct spi_board_info {
char modalias[SPI_NAME_SIZE];
const void * platform_data;
void * controller_data;
int irq;
u32 max_speed_hz;
u16 bus_num;
u16 chip_select;
u8 mode;
};
MEMBERS
modalias[SPI_NAME_SIZE]
Initializes spi_device.modalias; identifies the driver.
platform_data
Initializes spi_device.platform_data; the particular data stored
there is driver-specific.
controller_data
Initializes spi_device.controller_data; some controllers need hints
about hardware setup, e.g. for DMA.
irq
Initializes spi_device.irq; depends on how the board is wired.
max_speed_hz
Initializes spi_device.max_speed_hz; based on limits from the chip
datasheet and board-specific signal quality issues.
bus_num
Identifies which spi_master parents the spi_device; unused by
spi_new_device, and otherwise depends on board wiring.
chip_select
Initializes spi_device.chip_select; depends on how the board is
wired.
mode
Initializes spi_device.mode; based on the chip datasheet, board
wiring (some devices support both 3WIRE and standard modes), and
possibly presence of an inverter in the chipselect path.
DESCRIPTION
When adding new SPI devices to the device tree, these structures serve
as a partial device template. They hold information which can´t always
be determined by drivers. Information that probe can establish (such as
the default transfer wordsize) is not included here.
These structures are used in two places. Their primary role is to be
stored in tables of board-specific device descriptors, which are
declared early in board initialization and then used (much later) to
populate a controller´s device tree after the that controller´s driver
initializes. A secondary (and atypical) role is as a parameter to
spi_new_device call, which happens after those controller drivers are
active in some dynamic board configuration models.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 STRUCT SPI_BOARD_INF(9)
