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struct_spi_device(9) [centos man page]

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]; int cs_gpio; }; 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 cs_gpio gpio number of the chipselect line (optional, -ENOENT when when not using a GPIO line) 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 3.10 June 2014 STRUCT SPI_DEVICE(9)

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SPI_DRIVER(9) Serial Peripheral Interface (S STRUCT SPI_DRIVER(9) NAME
struct_spi_driver - Host side "protocol" driver SYNOPSIS
struct spi_driver { const struct spi_device_id * id_table; int (* probe) (struct spi_device *spi); int (* remove) (struct spi_device *spi); void (* shutdown) (struct spi_device *spi); int (* suspend) (struct spi_device *spi, pm_message_t mesg); int (* resume) (struct spi_device *spi); struct device_driver driver; }; MEMBERS
id_table List of SPI devices supported by this driver probe Binds this driver to the spi device. Drivers can verify that the device is actually present, and may need to configure characteristics (such as bits_per_word) which weren't needed for the initial configuration done during system setup. remove Unbinds this driver from the spi device shutdown Standard shutdown callback used during system state transitions such as powerdown/halt and kexec suspend Standard suspend callback used during system state transitions resume Standard resume callback used during system state transitions driver SPI device drivers should initialize the name and owner field of this structure. DESCRIPTION
This represents the kind of device driver that uses SPI messages to interact with the hardware at the other end of a SPI link. It's called a "protocol" driver because it works through messages rather than talking directly to SPI hardware (which is what the underlying SPI controller driver does to pass those messages). These protocols are defined in the specification for the device(s) supported by the driver. As a rule, those device protocols represent the lowest level interface supported by a driver, and it will support upper level interfaces too. Examples of such upper levels include frameworks like MTD, networking, MMC, RTC, filesystem character device nodes, and hardware monitoring. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 STRUCT SPI_DRIVER(9)

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