summaryrefslogtreecommitdiff
path: root/drivers/spi/davinci_spi.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/davinci_spi.c')
-rw-r--r--drivers/spi/davinci_spi.c54
1 files changed, 33 insertions, 21 deletions
diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
index 6beab99bf95b..1f0ed8005c91 100644
--- a/drivers/spi/davinci_spi.c
+++ b/drivers/spi/davinci_spi.c
@@ -571,6 +571,7 @@ static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
unsigned long tx_reg, rx_reg;
struct edmacc_param param;
void *rx_buf;
+ int b, c;
dma = &dspi->dma;
@@ -591,22 +592,38 @@ static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
if (t->tx_buf) {
t->tx_dma = dma_map_single(&spi->dev, (void *)t->tx_buf,
- dspi->wcount, DMA_TO_DEVICE);
+ t->len, DMA_TO_DEVICE);
if (dma_mapping_error(&spi->dev, t->tx_dma)) {
dev_dbg(sdev, "Unable to DMA map %d bytes"
- "TX buffer\n", dspi->wcount);
+ "TX buffer\n", t->len);
return -ENOMEM;
}
}
+ /*
+ * If number of words is greater than 65535, then we need
+ * to configure a 3 dimension transfer. Use the BCNTRLD
+ * feature to allow for transfers that aren't even multiples
+ * of 65535 (or any other possible b size) by first transferring
+ * the remainder amount then grabbing the next N blocks of
+ * 65535 words.
+ */
+
+ c = dspi->wcount / (SZ_64K - 1); /* N 65535 Blocks */
+ b = dspi->wcount - c * (SZ_64K - 1); /* Remainder */
+ if (b)
+ c++;
+ else
+ b = SZ_64K - 1;
+
param.opt = TCINTEN | EDMA_TCC(dma->tx_channel);
param.src = t->tx_buf ? t->tx_dma : tx_reg;
- param.a_b_cnt = dspi->wcount << 16 | data_type;
+ param.a_b_cnt = b << 16 | data_type;
param.dst = tx_reg;
param.src_dst_bidx = t->tx_buf ? data_type : 0;
- param.link_bcntrld = 0xffff;
- param.src_dst_cidx = 0;
- param.ccnt = 1;
+ param.link_bcntrld = 0xffffffff;
+ param.src_dst_cidx = t->tx_buf ? data_type : 0;
+ param.ccnt = c;
edma_write_slot(dma->tx_channel, &param);
edma_link(dma->tx_channel, dma->dummy_param_slot);
@@ -624,7 +641,7 @@ static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
if (t->rx_buf) {
rx_buf = t->rx_buf;
- rx_buf_count = dspi->rcount;
+ rx_buf_count = t->len;
} else {
rx_buf = dspi->rx_tmp_buf;
rx_buf_count = sizeof(dspi->rx_tmp_buf);
@@ -636,19 +653,19 @@ static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
dev_dbg(sdev, "Couldn't DMA map a %d bytes RX buffer\n",
rx_buf_count);
if (t->tx_buf)
- dma_unmap_single(NULL, t->tx_dma, dspi->wcount,
+ dma_unmap_single(NULL, t->tx_dma, t->len,
DMA_TO_DEVICE);
return -ENOMEM;
}
param.opt = TCINTEN | EDMA_TCC(dma->rx_channel);
param.src = rx_reg;
- param.a_b_cnt = dspi->rcount << 16 | data_type;
+ param.a_b_cnt = b << 16 | data_type;
param.dst = t->rx_dma;
param.src_dst_bidx = (t->rx_buf ? data_type : 0) << 16;
- param.link_bcntrld = 0xffff;
- param.src_dst_cidx = 0;
- param.ccnt = 1;
+ param.link_bcntrld = 0xffffffff;
+ param.src_dst_cidx = (t->rx_buf ? data_type : 0) << 16;
+ param.ccnt = c;
edma_write_slot(dma->rx_channel, &param);
if (pdata->cshold_bug)
@@ -675,7 +692,7 @@ static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
if (spicfg->io_type == SPI_IO_TYPE_DMA) {
if (t->tx_buf)
- dma_unmap_single(NULL, t->tx_dma, dspi->wcount,
+ dma_unmap_single(NULL, t->tx_dma, t->len,
DMA_TO_DEVICE);
dma_unmap_single(NULL, t->rx_dma, rx_buf_count,
@@ -790,7 +807,6 @@ static int davinci_spi_probe(struct platform_device *pdev)
struct resource *r, *mem;
resource_size_t dma_rx_chan = SPI_NO_RESOURCE;
resource_size_t dma_tx_chan = SPI_NO_RESOURCE;
- resource_size_t dma_eventq = SPI_NO_RESOURCE;
int i = 0, ret = 0;
u32 spipc0;
@@ -878,17 +894,13 @@ static int davinci_spi_probe(struct platform_device *pdev)
r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
if (r)
dma_tx_chan = r->start;
- r = platform_get_resource(pdev, IORESOURCE_DMA, 2);
- if (r)
- dma_eventq = r->start;
dspi->bitbang.txrx_bufs = davinci_spi_bufs;
if (dma_rx_chan != SPI_NO_RESOURCE &&
- dma_tx_chan != SPI_NO_RESOURCE &&
- dma_eventq != SPI_NO_RESOURCE) {
+ dma_tx_chan != SPI_NO_RESOURCE) {
dspi->dma.rx_channel = dma_rx_chan;
dspi->dma.tx_channel = dma_tx_chan;
- dspi->dma.eventq = dma_eventq;
+ dspi->dma.eventq = pdata->dma_event_q;
ret = davinci_spi_request_dma(dspi);
if (ret)
@@ -897,7 +909,7 @@ static int davinci_spi_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "DMA: supported\n");
dev_info(&pdev->dev, "DMA: RX channel: %d, TX channel: %d, "
"event queue: %d\n", dma_rx_chan, dma_tx_chan,
- dma_eventq);
+ pdata->dma_event_q);
}
dspi->get_rx = davinci_spi_rx_buf_u8;