Hi Jaehoon,
在 2016/11/17 15:53, Jaehoon Chung 写道:
When OWN bit of dma descriptor is not cleared, then it returns -EINVAL.
Then it has to fall back to PIO mode for current transfer.
Host controller was already set to bits relevant to DMA operation.
If needs to use the PIO mode, Host controller has to stop the DMA
operation. (It's more stable than now.)
It looks good to me, but
When it occurred error, it's not running any request.
Fixes: 3b2a067b98b4 ("mmc: dw_mmc: avoid race condition of cpu and IDMAC")
I think the real fixes tag should indicate the another commit,
3fc7eaef44dbcbcd60 ("mmc: dw_mmc: Add external dma interface support")
otherwise,
Reviewed-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
---
drivers/mmc/host/dw_mmc.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 9341b18..080003b 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1058,6 +1058,7 @@ static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
spin_unlock_irqrestore(&host->irq_lock, irqflags);
if (host->dma_ops->start(host, sg_len)) {
+ host->dma_ops->stop(host);
/* We can't do DMA, try PIO for this one */
dev_dbg(host->dev,
"%s: fall back to PIO mode for current transfer\n",
--
Best Regards
Shawn Lin
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
