From: Richard Genoud <richard.gen...@gmail.com>
Signed-off-by: Richard Genoud <richard.gen...@gmail.com>
Cc: grant.lik...@secretlab.ca
Cc: spi-devel-general@lists.sourceforge.net
---
drivers/spi/spi-atmel.c | 53 +++++++++++++++++++++++++++++++----------------
1 file changed, 35 insertions(+), 18 deletions(-)
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 0007a53..7a3613d 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -249,6 +249,8 @@ struct atmel_spi_device {
#define BUFFER_SIZE PAGE_SIZE
#define INVALID_DMA_ADDRESS 0xffffffff
+static struct dma_slave_config slave_config;
+
/*
* Version 2 of the SPI controller has
* - CR.LASTXFER
@@ -406,17 +408,41 @@ static bool filter(struct dma_chan *chan, void *slave)
}
}
+static int atmel_spi_set_dma_xfer_width(struct atmel_spi *as, u8 bits_per_word)
+{
+ int err = 0;
+
+ 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.direction = DMA_TO_DEVICE;
+ if (dmaengine_slave_config(as->dma.chan_tx, &slave_config)) {
+ dev_err(&as->pdev->dev,
+ "failed to configure tx dma channel\n");
+ err = -EINVAL;
+ }
+
+ slave_config.direction = DMA_FROM_DEVICE;
+ if (dmaengine_slave_config(as->dma.chan_rx, &slave_config)) {
+ dev_err(&as->pdev->dev,
+ "failed to configure rx dma channel\n");
+ err = -EINVAL;
+ }
+ return err;
+}
+
static int __devinit atmel_spi_configure_dma(struct atmel_spi *as)
{
struct at_dma_slave *sdata = (struct at_dma_slave *)&as->data.dma_slave;
- struct dma_slave_config slave_config;
int err;
- memset(&slave_config, 0, sizeof(slave_config));
slave_config.dst_addr = (dma_addr_t)as->phybase + SPI_TDR;
slave_config.src_addr = (dma_addr_t)as->phybase + SPI_RDR;
- slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
- slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
slave_config.src_maxburst = 1;
slave_config.dst_maxburst = 1;
slave_config.device_fc = false;
@@ -439,21 +465,9 @@ static int __devinit atmel_spi_configure_dma(struct
atmel_spi *as)
goto error;
}
- slave_config.direction = DMA_TO_DEVICE;
- if (dmaengine_slave_config(as->dma.chan_tx, &slave_config)) {
- dev_err(&as->pdev->dev,
- "failed to configure tx dma channel\n");
- err = -EINVAL;
+ err = atmel_spi_set_dma_xfer_width(as, 8);
+ if (err)
goto error;
- }
-
- slave_config.direction = DMA_FROM_DEVICE;
- if (dmaengine_slave_config(as->dma.chan_rx, &slave_config)) {
- dev_err(&as->pdev->dev,
- "failed to configure rx dma channel\n");
- err = -EINVAL;
- goto error;
- }
dev_info(&as->pdev->dev, "Using %s (tx) and " \
" %s (rx) for DMA transfers\n",
@@ -575,6 +589,9 @@ static int atmel_spi_next_xfer_dma(struct spi_master
*master,
memset(as->buffer, 0, xfer->len);
}
+ if (atmel_spi_set_dma_xfer_width(as, xfer->bits_per_word))
+ goto err_dma;
+
/* Send both scatterlists */
rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
&as->dma.sgrx,
--
1.7.9.5
------------------------------------------------------------------------------
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