From: Matthias Reichl <hias@xxxxxxxxx> commit 2201ac6129fa162ac24da089a034bb0971648ebb upstream. The code responsible for splitting periods into chunks that can be handled by the DMA controller missed to update total_len, the number of bytes processed in the current period, when there are more chunks to follow. Therefore total_len was stuck at 0 and the code didn't work at all. This resulted in a wrong control block layout and audio issues because the cyclic DMA callback wasn't executing on period boundaries. Fix this by adding the missing total_len update. Signed-off-by: Matthias Reichl <hias@xxxxxxxxx> Signed-off-by: Martin Sperl <kernel@xxxxxxxxxxxxxxxx> Tested-by: Clive Messer <clive.messer@xxxxxxxxxxxxxxxxxxxxxx> Reviewed-by: Eric Anholt <eric@xxxxxxxxxx> Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx> Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx> --- drivers/dma/bcm2835-dma.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c index e18dc596cf24..6204cc32d09c 100644 --- a/drivers/dma/bcm2835-dma.c +++ b/drivers/dma/bcm2835-dma.c @@ -251,8 +251,11 @@ static void bcm2835_dma_create_cb_set_length( */ /* have we filled in period_length yet? */ - if (*total_len + control_block->length < period_len) + if (*total_len + control_block->length < period_len) { + /* update number of bytes in this period so far */ + *total_len += control_block->length; return; + } /* calculate the length that remains to reach period_length */ control_block->length = period_len - *total_len; -- 2.7.4