From a99aa9b9b4f4f3e496d17a1b4e0ff63fb0c9f31d Mon Sep 17 00:00:00 2001
From: Seungwon Jeon <tgih.jun@samsung.com>
Date: Tue, 10 Apr 2012 09:53:32 +0900
Subject: [PATCH] mmc: dw_mmc: Fix switch from DMA to PIO

When dw_mci_pre_dma_transfer returns failure in some reasons,
dw_mci_submit_data will prepare to switch the PIO mode from DMA.
After switching to PIO mode, DMA(IDMAC in particular) is still
enabled. This makes the corruption in handling interrupt and
the driver lock-up.

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
---
 drivers/mmc/host/dw_mmc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index bf3c9b456aaf10..f3b0fcd002df84 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -526,8 +526,10 @@ static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
 		return -ENODEV;
 
 	sg_len = dw_mci_pre_dma_transfer(host, data, 0);
-	if (sg_len < 0)
+	if (sg_len < 0) {
+		host->dma_ops->stop(host);
 		return sg_len;
+	}
 
 	host->using_dma = 1;
 
-- 
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