From: Kuninori Morimoto Date: Tue, 3 Jul 2018 00:29:29 +0000 (+0000) Subject: dmaengine: rcar-dmac: clear channel register when error X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e919417bd6468b7f1b2899200a78f1ad078757d3;p=linux.git dmaengine: rcar-dmac: clear channel register when error We need to clear channel register in error case as recovery. The channel is already stopped in such case, thus we don't need to call rcar_dmac_chan_halt() before clearing. rcar_dmac_chan_halt() will clear and confirm DE bit. But it will be failed because channel is already stopped in error case. In other words, we shouldn't call it then. Reported-by: Hiroki Negishi Signed-off-by: Kuninori Morimoto Reviewed-by: Hiroki Negishi Reviewed-by: Simon Horman Signed-off-by: Vinod Koul --- diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index af2f2639cec9b..9dc73ac92359d 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -1522,7 +1522,15 @@ static irqreturn_t rcar_dmac_isr_channel(int irq, void *dev) chcr = rcar_dmac_chan_read(chan, RCAR_DMACHCR); if (chcr & RCAR_DMACHCR_CAE) { - rcar_dmac_chan_halt(chan); + struct rcar_dmac *dmac = to_rcar_dmac(chan->chan.device); + + /* + * We don't need to call rcar_dmac_chan_halt() + * because channel is already stopped in error case. + * We need to clear register and check DE bit as recovery. + */ + rcar_dmac_write(dmac, RCAR_DMACHCLR, 1 << chan->index); + rcar_dmac_chcr_de_barrier(chan); reinit = true; goto spin_lock_end; }