Unverified Commit 988f259b authored by Boris Brezillon's avatar Boris Brezillon Committed by Mark Brown
Browse files

spi: Add an helper to flush the message queue 



This is needed by the spi-mem logic to force all messages that have been
queued before a memory operation to be sent before we start the memory
operation. We do that in order to guarantee that spi-mem operations do
not preempt regular SPI transfers.

Signed-off-by: default avatarBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 46336966

drivers/spi/internals.h

+2 −0
Original line number Diff line number Diff line
@@ -17,6 +17,8 @@ 
#include <linux/scatterlist.h>

#include <linux/spi/spi.h>



void spi_flush_queue(struct spi_controller *ctrl);



#ifdef CONFIG_HAS_DMA

int spi_map_buf(struct spi_controller *ctlr, struct device *dev,

		struct sg_table *sgt, void *buf, size_t len,

drivers/spi/spi.c

+16 −0
Original line number Diff line number Diff line
@@ -1522,6 +1522,22 @@ err_init_queue: 
	return ret;

}



/**

 * spi_flush_queue - Send all pending messages in the queue from the callers'

 *		     context

 * @ctlr: controller to process queue for

 *

 * This should be used when one wants to ensure all pending messages have been

 * sent before doing something. Is used by the spi-mem code to make sure SPI

 * memory operations do not preempt regular SPI transfers that have been queued

 * before the spi-mem operation.

 */

void spi_flush_queue(struct spi_controller *ctlr)

{

	if (ctlr->transfer == spi_queued_transfer)

		__spi_pump_messages(ctlr, false);

}



/*-------------------------------------------------------------------------*/



#if defined(CONFIG_OF)

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