From: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
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 <hiroki.negishi.bx@xxxxxxxxxxx>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
Reviewed-by: Hiroki Negishi <hiroki.negishi.bx@xxxxxxxxxxx>
---
v1 -> v2
- use /* */ style comment instead of C++ style
- Cc:ed to Negishi-san
drivers/dma/sh/rcar-dmac.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c
index 279c930..a65292d 100644
--- a/drivers/dma/sh/rcar-dmac.c
+++ b/drivers/dma/sh/rcar-dmac.c
@@ -1525,7 +1525,15 @@ 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 = dev_get_drvdata(chan->chan.device->dev);
+
+ /*
+ * 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;
}
--
2.7.4
