sata_rcar: clear STOP bit in bmdma_start() method
Iff bmdma_setup() has to stop a DMA transfer before starting a new
one, then the STOP bit in the ATAPI_CONTROL1 register will remain set
(it's only cleared when setting the START bit to 1) and then
bmdma_start() method will set both START and STOP bits simultaneously
which should abort the transfer being just started. Avoid that by
explicitly clearing the STOP bit in bmdma_start() method (in this case
it will be ignored on write).
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
diff --git a/drivers/ata/sata_rcar.c b/drivers/ata/sata_rcar.c
index 4799868..a8e091a 100644
--- a/drivers/ata/sata_rcar.c
+++ b/drivers/ata/sata_rcar.c
@@ -549,6 +549,7 @@
/* start host DMA transaction */
dmactl = ioread32(priv->base + ATAPI_CONTROL1_REG);
+ dmactl &= ~ATAPI_CONTROL1_STOP;
dmactl |= ATAPI_CONTROL1_START;
iowrite32(dmactl, priv->base + ATAPI_CONTROL1_REG);
}