diff options
| author | Vitja Makarov <vitja.makarov@gmail.com> | 2008-05-01 04:35:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-05-01 08:04:01 -0700 |
| commit | 8eeb12e5a2486ab958fa27ec97e71dabf234b73b (patch) | |
| tree | e84a02583b607b7c2fe73878a121b196082d477a /drivers/spi | |
| parent | ef3fb66ced1a890769d71a4f4ae9f68b8afa98b6 (diff) | |
| download | lwn-8eeb12e5a2486ab958fa27ec97e71dabf234b73b.tar.gz lwn-8eeb12e5a2486ab958fa27ec97e71dabf234b73b.zip | |
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.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c index a9ac1fdb3094..7fea3cf4588a 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)); |