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authorLinus Torvalds2011-03-18 18:56:02 +0100
committerLinus Torvalds2011-03-18 18:56:02 +0100
commitb061c59c27e0385e53c961d9fbd18c1c078d9823 (patch)
tree56240ef8e98e9e4712ee58aa8e6e3d51f6ab001f /drivers/spi/davinci_spi.c
parentMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tei... (diff)
parentspi/dw_spi: move dw_spi.h into drivers/spi (diff)
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Merge branch 'spi/next' of git://git.secretlab.ca/git/linux-2.6
* 'spi/next' of git://git.secretlab.ca/git/linux-2.6: (34 commits) spi/dw_spi: move dw_spi.h into drivers/spi spi/dw_spi: Fix missing header gpio/langwell: Clear edge bit before handling gpio/langwell: Simplify demux loop gpio/langwell: Convert irq name space gpio/langwell: Fix broken irq_eoi change. gpio; Make Intel chipset gpio drivers depend on x86 gpio/cs5535-gpio: Fix section mismatch spi/rtc-{ds1390,ds3234,m41t94}: Use spi_get_drvdata() for SPI devices spi/davinci: Support DMA transfers larger than 65535 words spi/davinci: Use correct length parameter to dma_map_single calls gpio: Use __devexit at necessary places gpio: add MODULE_DEVICE_TABLE to pch_gpio and ml_ioh_gpio gpio/mcp23s08: support mcp23s17 variant of_mmc_spi: add card detect irq support spi/omap_mcspi: catch xfers of non-multiple SPI word size spi/omap_mcspi: Off-by-one error in finding the right divisor gpio/pca953x: Fix wrong pointer type spi/pl022: rid dangling labels spi: add support for SuperH SPI ...
Diffstat (limited to 'drivers/spi/davinci_spi.c')
-rw-r--r--drivers/spi/davinci_spi.c43
1 files changed, 30 insertions, 13 deletions
diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
index 166a879fd9e8..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,