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Subject[PATCH 4.4 47/88] spi: bcm2835: Fix book-keeping of DMA termination
4.4-stable review patch.  If anyone has any objections, please let me know.


From: Lukas Wunner <>

commit dbc944115eed48af110646992893dc43321368d8 upstream.

If submission of a DMA TX transfer succeeds but submission of the
corresponding RX transfer does not, the BCM2835 SPI driver terminates
the TX transfer but neglects to reset the dma_pending flag to false.

Thus, if the next transfer uses interrupt mode (because it is shorter
than BCM2835_SPI_DMA_MIN_LENGTH) and runs into a timeout,
dmaengine_terminate_all() will be called both for TX (once more) and
for RX (which was never started in the first place). Fix it.

Signed-off-by: Lukas Wunner <>
Fixes: 3ecd37edaa2a ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Cc: # v4.2+
Cc: Mathias Duckeck <>
Cc: Frank Pavlic <>
Cc: Martin Sperl <>
Cc: Noralf Trønnes <>
Signed-off-by: Mark Brown <>
Signed-off-by: Greg Kroah-Hartman <>

drivers/spi/spi-bcm2835.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -341,6 +341,7 @@ static int bcm2835_spi_transfer_one_dma(
if (ret) {
/* need to reset on errors */
+ bs->dma_pending = false;
return ret;

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