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spi: dw-mid: clear BUSY flag fist and test other one 

The logic of DMA completion is broken now since test_and_clear_bit() never
returns the other bit is set. It means condition are always false and we have
spi_finalize_current_transfer() called per each DMA completion which is wrong.

The patch fixes logic by clearing BUSY bit first and then check for the other
one.

Fixes: 30c8eb52cc (spi: dw-mid: split rx and tx callbacks when DMA)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This commit is contained in:
Andy Shevchenko 2015-03-06 14:42:01 +02:00 committed by Mark Brown
parent c9dafb27c8
commit 854d2f241d
1 changed files with 4 additions and 2 deletions
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6
drivers/spi/spi-dw-mid.c
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@ -108,7 +108,8 @@ static void dw_spi_dma_tx_done(void *arg)
{
struct dw_spi *dws = arg;
if (test_and_clear_bit(TX_BUSY, &dws->dma_chan_busy) & BIT(RX_BUSY))
clear_bit(TX_BUSY, &dws->dma_chan_busy);
if (test_bit(RX_BUSY, &dws->dma_chan_busy))
return;
dw_spi_xfer_done(dws);
}
@ -156,7 +157,8 @@ static void dw_spi_dma_rx_done(void *arg)
{
struct dw_spi *dws = arg;
if (test_and_clear_bit(RX_BUSY, &dws->dma_chan_busy) & BIT(TX_BUSY))
clear_bit(RX_BUSY, &dws->dma_chan_busy);
if (test_bit(TX_BUSY, &dws->dma_chan_busy))
return;
dw_spi_xfer_done(dws);
}