[PATCH] spi: spi-fsl-dspi: Fill actual_length when doing DMA transfer

From: Andrey Smirnov
Date: Tue Jul 17 2018 - 00:33:29 EST


Upper layer users of SPI device drivers may rely on 'actual_length',
so it is important that information is correctly reported. One such
example is spi_mem_exec_op() function that will fail if
'actual_length' of the data transferred is not what was requested. Add
necessary code to populate 'actual_length.

Cc: Mark Brown <broonie@xxxxxxxxxx>
Cc: Sanchayan Maity <maitysanchayan@xxxxxxxxx>
Cc: Stefan Agner <stefan@xxxxxxxx>
Cc: cphealy@xxxxxxxxx
Cc: linux-spi@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi-fsl-dspi.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index 89a1e7a4fe5d..9e598642ca66 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/drivers/spi/spi-fsl-dspi.c
@@ -358,6 +358,7 @@ static int dspi_dma_xfer(struct fsl_dspi *dspi)
{
struct fsl_dspi_dma *dma = dspi->dma;
struct device *dev = &dspi->pdev->dev;
+ struct spi_message *message = dspi->cur_msg;
int curr_remaining_bytes;
int bytes_per_buffer;
int ret = 0;
@@ -377,8 +378,10 @@ static int dspi_dma_xfer(struct fsl_dspi *dspi)
goto exit;

} else {
- curr_remaining_bytes -= dma->curr_xfer_len
- * dspi->bytes_per_word;
+ const int len =
+ dma->curr_xfer_len * dspi->bytes_per_word;
+ curr_remaining_bytes -= len;
+ message->actual_length += len;
if (curr_remaining_bytes < 0)
curr_remaining_bytes = 0;
}
--
2.18.0