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authorVitja Makarov <vitja.makarov@gmail.com>2008-05-01 04:35:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-05-01 08:04:01 -0700
commit8eeb12e5a2486ab958fa27ec97e71dabf234b73b (patch)
treee84a02583b607b7c2fe73878a121b196082d477a /drivers/spi
parentef3fb66ced1a890769d71a4f4ae9f68b8afa98b6 (diff)
downloadop-kernel-dev-8eeb12e5a2486ab958fa27ec97e71dabf234b73b.zip
op-kernel-dev-8eeb12e5a2486ab958fa27ec97e71dabf234b73b.tar.gz
spi_bfin5xx: use PIO for full duplex, not DMA
Use PIO for full-duplex transfers, instead of DMA. Signed-off-by: Vitja Makarov <vitja.makarov@gmail.com> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/spi_bfin5xx.c7
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index a9ac1fd..7fea3cf 100644
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -608,6 +608,7 @@ static void pump_transfers(unsigned long data)
u8 width;
u16 cr, dma_width, dma_config;
u32 tranf_success = 1;
+ u8 full_duplex = 0;
/* Get current state information */
message = drv_data->cur_msg;
@@ -658,6 +659,7 @@ static void pump_transfers(unsigned long data)
}
if (transfer->rx_buf != NULL) {
+ full_duplex = transfer->tx_buf != NULL;
drv_data->rx = transfer->rx_buf;
drv_data->rx_end = drv_data->rx + transfer->len;
dev_dbg(&drv_data->pdev->dev, "rx_buf is %p, rx_end is %p\n",
@@ -740,7 +742,8 @@ static void pump_transfers(unsigned long data)
* successful use different way to r/w according to
* drv_data->cur_chip->enable_dma
*/
- if (drv_data->cur_chip->enable_dma && drv_data->len > 6) {
+ if (!full_duplex && drv_data->cur_chip->enable_dma
+ && drv_data->len > 6) {
disable_dma(drv_data->dma_channel);
clear_dma_irqstat(drv_data->dma_channel);
@@ -828,7 +831,7 @@ static void pump_transfers(unsigned long data)
/* IO mode write then read */
dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n");
- if (drv_data->tx != NULL && drv_data->rx != NULL) {
+ if (full_duplex) {
/* full duplex mode */
BUG_ON((drv_data->tx_end - drv_data->tx) !=
(drv_data->rx_end - drv_data->rx));
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