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struct_spi_device(9) [suse man page]

STRUCT 
SPI_DEVICE(9)					  Serial Peripheral Interface (S				      STRUCT SPI_DEVICE(9)

NAME

       struct_spi_device - Master side proxy for an SPI slave device

SYNOPSIS

       struct spi_device {
	 struct device dev;
	 struct spi_master * master;
	 u32 max_speed_hz;
	 u8 chip_select;
	 u8 mode;
       #define SPI_CPHA    0x01
       #define SPI_CPOL    0x02
       #define SPI_MODE_0  (0|0)
       #define SPI_MODE_1  (0|SPI_CPHA)
       #define SPI_MODE_2  (SPI_CPOL|0)
       #define SPI_MODE_3  (SPI_CPOL|SPI_CPHA)
       #define SPI_CS_HIGH 0x04
       #define SPI_LSB_FIRST	0x08
       #define SPI_3WIRE   0x10
       #define SPI_LOOP    0x20
       #define SPI_NO_CS   0x40
       #define SPI_READY   0x80
	 u8 bits_per_word;
	 int irq;
	 void * controller_state;
	 void * controller_data;
	 char modalias[SPI_NAME_SIZE];
       };

MEMBERS

       dev
	   Driver model representation of the device.

       master
	   SPI controller used with the device.

       max_speed_hz
	   Maximum clock rate to be used with this chip (on this board); may be changed by the device's driver. The spi_transfer.speed_hz can
	   override this for each transfer.

       chip_select
	   Chipselect, distinguishing chips handled by master.

       mode
	   The spi mode defines how data is clocked out and in. This may be changed by the device's driver. The "active low" default for
	   chipselect mode can be overridden (by specifying SPI_CS_HIGH) as can the "MSB first" default for each word in a transfer (by specifying
	   SPI_LSB_FIRST).

       bits_per_word
	   Data transfers involve one or more words; word sizes like eight or 12 bits are common. In-memory wordsizes are powers of two bytes
	   (e.g. 20 bit samples use 32 bits). This may be changed by the device's driver, or left at the default (0) indicating protocol words are
	   eight bit bytes. The spi_transfer.bits_per_word can override this for each transfer.

       irq
	   Negative, or the number passed to request_irq to receive interrupts from this device.

       controller_state
	   Controller's runtime state

       controller_data
	   Board-specific definitions for controller, such as FIFO initialization parameters; from board_info.controller_data

       modalias[SPI_NAME_SIZE]
	   Name of the driver to use with this device, or an alias for that name. This appears in the sysfs "modalias" attribute for driver
	   coldplugging, and in uevents used for hotplugging

DESCRIPTION

       A spi_device is used to interchange data between an SPI slave (usually a discrete chip) and CPU memory.

       In dev, the platform_data is used to hold information about this device that's meaningful to the device's protocol driver, but not to its
       controller. One example might be an identifier for a chip variant with slightly different functionality; another might be information about
       how this particular board wires the chip's pins.

COPYRIGHT

Kernel Hackers Manual 2.6.					     July 2010						      STRUCT SPI_DEVICE(9)

Check Out this Related Man Page

STRUCT 
SPI_MASTER(9)					  Serial Peripheral Interface (S				      STRUCT SPI_MASTER(9)

NAME

       struct_spi_master - interface to SPI master controller

SYNOPSIS

       struct spi_master {
	 struct device dev;
	 s16 bus_num;
	 u16 num_chipselect;
	 u16 dma_alignment;
	 u16 mode_bits;
	 u16 flags;
       #define SPI_MASTER_HALF_DUPLEX	  BIT(0)
       #define SPI_MASTER_NO_RX BIT(1)
       #define SPI_MASTER_NO_TX BIT(2)
	 int (* setup) (struct spi_device *spi);
	 int (* transfer) (struct spi_device *spi,struct spi_message *mesg);
	 void (* cleanup) (struct spi_device *spi);
       };

MEMBERS

       dev
	   device interface to this driver

       bus_num
	   board-specific (and often SOC-specific) identifier for a given SPI controller.

       num_chipselect
	   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.

       dma_alignment
	   SPI controller constraint on DMA buffers alignment.

       mode_bits
	   flags understood by this controller driver

       flags
	   other constraints relevant to this driver

       setup
	   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.

       transfer
	   adds a message to the controller's transfer queue.

       cleanup
	   frees controller-specific state

DESCRIPTION

       Each SPI master controller can communicate with one or more spi_device 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.

COPYRIGHT

Kernel Hackers Manual 2.6.					     July 2010						      STRUCT SPI_MASTER(9)
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