Unverified Commit 39cefd85 authored by Nam Cao's avatar Nam Cao Committed by Mark Brown
Browse files

spi: introduce SPI_TRANS_FAIL_IO for error reporting 



The default message transfer implementation - spi_transfer_one_message -
invokes the specific device driver's transfer_one(), then waits for
completion. However, there is no mechanism for the device driver to
report failure in the middle of the transfer.

Introduce SPI_TRANS_FAIL_IO for drivers to report transfer failure.

Signed-off-by: default avatarNam Cao <namcao@linutronix.de>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/4b420dac528e60f122adde16851da88e4798c1ea.1701274975.git.namcao@linutronix.de


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 2cc14f52

drivers/spi/spi.c

+3 −0
Original line number Diff line number Diff line
@@ -1361,6 +1361,9 @@ static int spi_transfer_wait(struct spi_controller *ctlr, 
				"SPI transfer timed out\n");

			return -ETIMEDOUT;

		}



		if (xfer->error & SPI_TRANS_FAIL_IO)

			return -EIO;

	}



	return 0;

include/linux/spi/spi.h

+8 −4
Original line number Diff line number Diff line
@@ -461,10 +461,13 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch 
 *                  - return 1 if the transfer is still in progress. When

 *                    the driver is finished with this transfer it must

 *                    call spi_finalize_current_transfer() so the subsystem

 *                    can issue the next transfer. Note: transfer_one and

 *                    transfer_one_message are mutually exclusive; when both

 *                    are set, the generic subsystem does not call your

 *                    transfer_one callback.

 *                    can issue the next transfer. If the transfer fails, the

 *                    driver must set the flag SPI_TRANS_FAIL_IO to

 *                    spi_transfer->error first, before calling

 *                    spi_finalize_current_transfer().

 *                    Note: transfer_one and transfer_one_message are mutually

 *                    exclusive; when both are set, the generic subsystem does

 *                    not call your transfer_one callback.

 * @handle_err: the subsystem calls the driver to handle an error that occurs

 *		in the generic implementation of transfer_one_message().

 * @mem_ops: optimized/dedicated operations for interactions with SPI memory.
@@ -1040,6 +1043,7 @@ struct spi_transfer { 
	unsigned	len;



#define SPI_TRANS_FAIL_NO_START	BIT(0)

#define SPI_TRANS_FAIL_IO	BIT(1)

	u16		error;



	dma_addr_t	tx_dma;