linux/spi/spi.h

51  *                 transfer bytes histogramm
117  *	The spi_transfer.speed_hz can override this for each transfer.
123  *	each word in a transfer (by specifying SPI_LSB_FIRST).
129  *	The spi_transfer.bits_per_word can override this for each transfer.
147  *	words of a transfer
341  *	supported. If set, the SPI core will reject any transfer with an
344  * @min_speed_hz: Lowest supported transfer speed
345  * @max_speed_hz: Highest supported transfer speed
348  * @max_transfer_size: function that returns the max transfer size for
364  * @transfer: adds a message to the controller's transfer queue.
386  * @max_dma_len: Maximum length of a DMA transfer for the device.
388  *	so the subsystem requests the driver to prepare the transfer hardware
390  * @transfer_one_message: the subsystem calls the driver to transfer a single
401  * @prepare_message: set up the controller to transfer a single message,
404  * @transfer_one: transfer a single spi_transfer.
406  *                  - return 0 if the transfer is finished,
407  *                  - return 1 if the transfer is still in progress. When
408  *                    the driver is finished with this transfer it must
410  *                    can issue the next transfer. Note: transfer_one and
420  * @slave_abort: abort the ongoing transfer request on an SPI slave controller
458  * @fallback: fallback to pio if dma transfer return failure with
506 	/* limits on transfer speed */
524 	 * on some hardware transfer / message size may be constrained
525 	 * the limit may depend on device transfer settings
561 	 * + The transfer() method may not sleep; its main role is
578 	int			(*transfer)(struct spi_device *spi,  member
586 	 * exists and returns true then the transfer will be mapped
597 	 * controller transfer queueing mechanism. If these are used, the
598 	 * transfer() function above must NOT be specified by the driver.
636 			    struct spi_transfer *transfer);
726 /* Helper calls for driver to timestamp transfer */
819  * The spi_messages themselves consist of a series of read+write transfer
842  *      transfer. If 0 the default (from @spi_device) is used.
844  *      for this transfer. If 0 the default (from @spi_device) is used.
845  * @cs_change: affects chipselect after this transfer completes
848  * @delay: delay to be introduced after this transfer before
850  *	the next transfer or completing this @spi_message.
851  * @delay_usecs: microseconds to delay after this transfer before
853  *	the next transfer or completing this @spi_message.
857  *      transfer this transfer. Set to 0 if the spi bus driver does
864  *	snapshot for this transfer begins. Upon completing the SPI transfer,
866  *	on the available snapshotting resolution (DMA transfer,
872  *	@ptp_sts_word_post to the length of the transfer. This is done
874  *	that a transfer-level snapshot taken from within the driver may still
878  *	hardware has some sort of assist for retrieving exact transfer timing,
885  * @timestamped: true if the transfer has been timestamped
906  * When the word size of the SPI transfer is not a power-of-two multiple
912  * it stays selected until after the last transfer in a message.  Drivers
915  * (i) If the transfer isn't the last one in the message, this flag is
921  * (ii) When the transfer is the last one in the message, the chip may
922  * stay selected until the next transfer.  On multi-device SPI busses
931  * When SPI can transfer in 1x,2x or 4x. It can get this transfer information
933  * two should both be set. User can set transfer mode with SPI_NBITS_SINGLE(1x)
934  * SPI_NBITS_DUAL(2x) and SPI_NBITS_QUAD(4x) to support these three transfer.
960 #define	SPI_NBITS_SINGLE	0x01 /* 1bit transfer */
961 #define	SPI_NBITS_DUAL		0x02 /* 2bits transfer */
962 #define	SPI_NBITS_QUAD		0x04 /* 4bits transfer */
989  * @transfers: list of transfer segments in this transaction
992  *	addresses for each transfer buffer
1007  * a single programmed DMA transfer.  On all systems, these messages are
1025 	 * last transfer ... allowing things like "read 16 bit length L"
1171 	/* transfer size limit must not be greater than messsage size limit */  in spi_max_transfer_size()
1197 /* SPI transfer replacement methods which make use of spi_res */
1212  * @replaced_after:     the transfer after which the @replaced_transfers
1242 /* SPI transfer transformation methods */
1251 /* All these synchronous SPI transfer routines are utilities layered
1252  * over the core async transfer primitive.  Here, "synchronous" means
1253  * they will sleep uninterruptibly until the async transfer completes.
1262  * spi_sync_transfer - synchronous SPI data transfer
1268  * Does a synchronous SPI data transfer of the given spi_transfer array.
1448  * as the default transfer wordsize) is not included here.