[v2 PATCH 09/14] spi/atmel_spi: Fix spi-atmel driver to adapt to slave_config changes
Wenyou Yang
wenyou.yang at atmel.com
Tue Dec 4 02:53:55 EST 2012
From: Richard Genoud <richard.genoud at gmail.com>
This is the following of the patch e2b35f3dbfc080f15b72834d08f04f0269dbe9be
Signed-off-by: Richard Genoud <richard.genoud at gmail.com>
[wenyou.yang at atmel.com: fix DMA: when enable both spi0 and spi1, spi0 doesn't work]
Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
Cc: grant.likely at secretlab.ca
Cc: spi-devel-general at lists.sourceforge.net
---
drivers/spi/spi-atmel.c | 60 ++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 51 insertions(+), 9 deletions(-)
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 1de45c2..7f624b6 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -438,6 +438,37 @@ static inline int atmel_spi_xfer_can_be_chained(struct spi_transfer *xfer)
return xfer->delay_usecs == 0 && !xfer->cs_change;
}
+static int atmel_spi_dma_slave_config(struct atmel_spi *as,
+ struct dma_slave_config *slave_config)
+{
+ int err = 0;
+
+ 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;
+ slave_config->src_maxburst = 1;
+ slave_config->dst_maxburst = 1;
+ slave_config->device_fc = false;
+
+ slave_config->direction = DMA_MEM_TO_DEV;
+ 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_DEV_TO_MEM;
+ 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 bool filter(struct dma_chan *chan, void *slave)
{
struct at_dma_slave *sl = slave;
@@ -454,14 +485,12 @@ static int __devinit atmel_spi_configure_dma(struct atmel_spi *as)
{
struct at_dma_slave *sdata
= (struct at_dma_slave *)&as->pdata->dma_slave;
+ struct dma_slave_config slave_config;
+ int err;
if (sdata && sdata->dma_dev) {
dma_cap_mask_t mask;
- /* setup DMA addresses */
- sdata->rx_reg = (dma_addr_t)as->phybase + SPI_RDR;
- sdata->tx_reg = (dma_addr_t)as->phybase + SPI_TDR;
-
/* Try to grab two DMA channels */
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
@@ -471,21 +500,28 @@ static int __devinit atmel_spi_configure_dma(struct atmel_spi *as)
dma_request_channel(mask, filter, sdata);
}
if (!as->dma.chan_rx || !as->dma.chan_tx) {
- if (as->dma.chan_rx)
- dma_release_channel(as->dma.chan_rx);
- if (as->dma.chan_tx)
- dma_release_channel(as->dma.chan_tx);
dev_err(&as->pdev->dev, "DMA channel not available, " \
"unable to use SPI\n");
- return -EBUSY;
+ err = -EBUSY;
+ goto error;
}
+ err = atmel_spi_dma_slave_config(as, &slave_config);
+ if (err)
+ goto error;
+
dev_info(&as->pdev->dev, "Using %s (tx) and " \
" %s (rx) for DMA transfers\n",
dma_chan_name(as->dma.chan_tx),
dma_chan_name(as->dma.chan_rx));
return 0;
+error:
+ if (as->dma.chan_rx)
+ dma_release_channel(as->dma.chan_rx);
+ if (as->dma.chan_tx)
+ dma_release_channel(as->dma.chan_tx);
+ return err;
}
static void atmel_spi_stop_dma(struct atmel_spi *as)
@@ -562,6 +598,7 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
struct dma_chan *txchan = as->dma.chan_tx;
struct dma_async_tx_descriptor *rxdesc;
struct dma_async_tx_descriptor *txdesc;
+ struct dma_slave_config slave_config;
dma_cookie_t cookie;
u32 len = *plen;
@@ -600,6 +637,10 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
*plen = len;
+ if (atmel_spi_dma_slave_config(as, &slave_config))
+ goto err_exit;
+
+
/* Send both scatterlists */
rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
&as->dma.sgrx,
@@ -648,6 +689,7 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
err_dma:
spi_writel(as, IDR, SPI_BIT(OVRES));
atmel_spi_stop_dma(as);
+err_exit:
atmel_spi_lock(as);
return -ENOMEM;
}
--
1.7.9.5
More information about the linux-arm-kernel
mailing list