Unverified Commit eeaceb8b authored by Baolin Wang's avatar Baolin Wang Committed by Mark Brown
Browse files

spi: Introduce one new field to set word delay 



For some SPI controllers, after each word size (specified by bits_per_word)
transimission, the hardware need some delay to make sure the slave has enough
time to receive the whole data.

So introducing one new 'word_delay' field of struct spi_tansfer for slave
devices to set this inter word delay time.

Signed-off-by: default avatarBaolin Wang <baolin.wang@linaro.org>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 86482223

include/linux/spi/spi.h

+3 −0
Original line number Diff line number Diff line
@@ -711,6 +711,8 @@ extern void spi_res_release(struct spi_controller *ctlr, 
 * @delay_usecs: microseconds to delay after this transfer before

 *	(optionally) changing the chipselect status, then starting

 *	the next transfer or completing this @spi_message.

 * @word_delay: clock cycles to inter word delay after each word size

 *	(set by bits_per_word) transmission.

 * @transfer_list: transfers are sequenced through @spi_message.transfers

 * @tx_sg: Scatterlist for transmit, currently not for client use

 * @rx_sg: Scatterlist for receive, currently not for client use
@@ -793,6 +795,7 @@ struct spi_transfer { 
	u8		bits_per_word;

	u16		delay_usecs;

	u32		speed_hz;

	u16		word_delay;



	struct list_head transfer_list;

};