From: Muhammad Hamza Farooq <mfarooq@xxxxxxxxxxx> The hardware might have complete the transfer but the interrupt handler might not have had a chance to run. If rcar_dmac_chan_get_residue() which reads HW registers finds that there is no residue return DMA_COMPLETE. Signed-off-by: Muhammad Hamza Farooq <mfarooq@xxxxxxxxxxx> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> [Niklas: add explanation in commit message] Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx> Acked-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> --- drivers/dma/sh/rcar-dmac.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index dfb1792..791a064 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -1202,6 +1202,10 @@ static enum dma_status rcar_dmac_tx_status(struct dma_chan *chan, residue = rcar_dmac_chan_get_residue(rchan, cookie); spin_unlock_irqrestore(&rchan->lock, flags); + /* if there's no residue, the cookie is complete */ + if (!residue) + return DMA_COMPLETE; + dma_set_residue(txstate, residue); return status; -- 2.9.0
