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STRUCT SPI_BOARD_INF(9) | Serial Peripheral Interface (S | STRUCT SPI_BOARD_INF(9) |
NAME¶
struct_spi_board_info - board-specific template for a SPI deviceSYNOPSIS¶
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; u16 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.COPYRIGHT¶
January 2017 | Kernel Hackers Manual 4.8. |