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-rw-r--r--drivers/spi/spi-atmel.c57
1 files changed, 25 insertions, 32 deletions
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 8f20d4f75e4a..7e03e221d307 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -268,8 +268,6 @@
struct atmel_spi_dma {
struct dma_chan *chan_rx;
struct dma_chan *chan_tx;
- struct scatterlist sgrx;
- struct scatterlist sgtx;
struct dma_async_tx_descriptor *data_desc_rx;
struct dma_async_tx_descriptor *data_desc_tx;
@@ -453,6 +451,15 @@ static inline bool atmel_spi_use_dma(struct atmel_spi *as,
return as->use_dma && xfer->len >= DMA_MIN_BYTES;
}
+static bool atmel_spi_can_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct atmel_spi *as = spi_master_get_devdata(master);
+
+ return atmel_spi_use_dma(as, xfer);
+}
+
static int atmel_spi_dma_slave_config(struct atmel_spi *as,
struct dma_slave_config *slave_config,
u8 bits_per_word)
@@ -720,7 +727,6 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
struct dma_async_tx_descriptor *txdesc;
struct dma_slave_config slave_config;
dma_cookie_t cookie;
- u32 len = *plen;
dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_dma_submit\n");
@@ -731,34 +737,22 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
/* release lock for DMA operations */
atmel_spi_unlock(as);
- /* prepare the RX dma transfer */
- sg_init_table(&as->dma.sgrx, 1);
- as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen;
-
- /* prepare the TX dma transfer */
- sg_init_table(&as->dma.sgtx, 1);
- as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen;
-
- if (len > master->max_dma_len)
- len = master->max_dma_len;
-
- sg_dma_len(&as->dma.sgtx) = len;
- sg_dma_len(&as->dma.sgrx) = len;
-
- *plen = len;
+ *plen = xfer->len;
if (atmel_spi_dma_slave_config(as, &slave_config,
xfer->bits_per_word))
goto err_exit;
/* Send both scatterlists */
- rxdesc = dmaengine_prep_slave_sg(rxchan, &as->dma.sgrx, 1,
+ rxdesc = dmaengine_prep_slave_sg(rxchan,
+ xfer->rx_sg.sgl, xfer->rx_sg.nents,
DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!rxdesc)
goto err_dma;
- txdesc = dmaengine_prep_slave_sg(txchan, &as->dma.sgtx, 1,
+ txdesc = dmaengine_prep_slave_sg(txchan,
+ xfer->tx_sg.sgl, xfer->tx_sg.nents,
DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!txdesc)
@@ -804,15 +798,10 @@ static void atmel_spi_next_xfer_data(struct spi_master *master,
dma_addr_t *rx_dma,
u32 *plen)
{
- struct atmel_spi *as = spi_master_get_devdata(master);
- u32 len = *plen;
-
*rx_dma = xfer->rx_dma + xfer->len - *plen;
*tx_dma = xfer->tx_dma + xfer->len - *plen;
- if (len > master->max_dma_len)
- len = master->max_dma_len;
-
- *plen = len;
+ if (*plen > master->max_dma_len)
+ *plen = master->max_dma_len;
}
static int atmel_spi_set_xfer_speed(struct atmel_spi *as,
@@ -1252,7 +1241,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
* better fault reporting.
*/
if ((!msg->is_dma_mapped)
- && (atmel_spi_use_dma(as, xfer) || as->use_pdc)) {
+ && as->use_pdc) {
if (atmel_spi_dma_map_xfer(as, xfer) < 0)
return -ENOMEM;
}
@@ -1329,7 +1318,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
}
if (!msg->is_dma_mapped
- && (atmel_spi_use_dma(as, xfer) || as->use_pdc))
+ && as->use_pdc)
atmel_spi_dma_unmap_xfer(master, xfer);
return 0;
@@ -1340,7 +1329,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
}
if (!msg->is_dma_mapped
- && (atmel_spi_use_dma(as, xfer) || as->use_pdc))
+ && as->use_pdc)
atmel_spi_dma_unmap_xfer(master, xfer);
if (xfer->delay_usecs)
@@ -1518,6 +1507,7 @@ static int atmel_spi_probe(struct platform_device *pdev)
master->cleanup = atmel_spi_cleanup;
master->auto_runtime_pm = true;
master->max_dma_len = SPI_MAX_DMA_XFER;
+ master->can_dma = atmel_spi_can_dma;
platform_set_drvdata(pdev, master);
as = spi_master_get_devdata(master);
@@ -1554,10 +1544,13 @@ static int atmel_spi_probe(struct platform_device *pdev)
as->use_pdc = false;
if (as->caps.has_dma_support) {
ret = atmel_spi_configure_dma(as);
- if (ret == 0)
+ if (ret == 0) {
+ master->dma_tx = as->dma.chan_tx;
+ master->dma_rx = as->dma.chan_rx;
as->use_dma = true;
- else if (ret == -EPROBE_DEFER)
+ } else if (ret == -EPROBE_DEFER) {
return ret;
+ }
} else {
as->use_pdc = true;
}