[PATCH 14/20] Blackfin SPI Driver: tweak magic spi dma sequence to get it working on BF54x

Bryan Wu
2009-02-06T07:16:14Z

Without this changes, SPI DMA is not reliably under stress tests.
Obiviously it's a hardware issue which is not addressed by any document.

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
---
drivers/spi/spi_bfin5xx.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index 748e98f..d8c4be1 100644
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -862,8 +862,9 @@ static void pump_transfers(unsigned long data)
set_dma_start_addr(drv_data->dma_channel, dma_start_addr);
set_dma_config(drv_data->dma_channel, dma_config);
local_irq_save(flags);
- enable_dma(drv_data->dma_channel);
+ SSYNC();
write_CTRL(drv_data, cr);
+ enable_dma(drv_data->dma_channel);
dma_enable_irq(drv_data->dma_channel);
local_irq_restore(flags);

--
1.5.6.3