[PATCH v6 11/16] spi/spi-atmel: correct 16 bits transfers with DMA

Wenyou Yang
2013-03-07T03:36:24Z

From: Richard Genoud <richard.genoud@gmail.com>

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Cc: spi-devel-general@lists.sourceforge.net
Cc: linux-kernel@vger.kernel.org
[wenyou.yang@atmel.com: submit the patch]
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---
drivers/spi/spi-atmel.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index d287889..1e212d1 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -388,12 +388,18 @@ static inline int atmel_spi_xfer_can_be_chained(struct spi_transfer *xfer)
}

static int atmel_spi_dma_slave_config(struct atmel_spi *as,
- struct dma_slave_config *slave_config)
+ struct dma_slave_config *slave_config,
+ u8 bits_per_word)
{
int err = 0;

- slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
- slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ if (bits_per_word > 8) {
+ slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ } else {
+ slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ }

slave_config->dst_addr = (dma_addr_t)as->phybase + SPI_TDR;
slave_config->src_addr = (dma_addr_t)as->phybase + SPI_RDR;
@@ -454,7 +460,7 @@ static int atmel_spi_configure_dma(struct atmel_spi *as)
goto error;
}

- err = atmel_spi_dma_slave_config(as, &slave_config);
+ err = atmel_spi_dma_slave_config(as, &slave_config, 8);
if (err)
goto error;

@@ -588,10 +594,9 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,

*plen = len;

- if (atmel_spi_dma_slave_config(as, &slave_config))
+ if (atmel_spi_dma_slave_config(as, &slave_config, 8))
goto err_exit;

-
/* Send both scatterlists */
rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
&as->dma.sgrx,
--
1.7.9.5