[PATCH 3/4] mmc: sunxi: Reset behavior fix

[David Lanzendörfer]

When there is only one DES available the DMA performs a FIFO reset and waits until the reinitialization has been completed.
Disabling the SDXC_IDMAC_DES0_DIC bit prevents the DMA from sending an interrupt after it has finished this reinitialization.

The flags SDXC_IDMAC_DES0_FD and SDXC_IDMAC_DES0_LD are both required in order to use the controller with more than one DES.

Signed-off-by: David Lanzendörfer <david.lanzendoerfer at o2s.ch>
Reported-by: 李想 <lixiang at allwinnertech.com>
---
 drivers/mmc/host/sunxi-mmc.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
index 50bd3d2..5331c88 100644
--- a/drivers/mmc/host/sunxi-mmc.c
+++ b/drivers/mmc/host/sunxi-mmc.c
@@ -310,7 +310,17 @@ static void sunxi_mmc_init_idma_des(struct sunxi_mmc_host *host,
 	}
 
 	pdes[0].config |= SDXC_IDMAC_DES0_FD;
-	pdes[i - 1].config = SDXC_IDMAC_DES0_OWN | SDXC_IDMAC_DES0_LD;
+
+	/*
+	 * When there is only one DES available the DMA performs a FIFO reset and waits
+	 * until the reinitialization has been completed.
+	 * Disabling the SDXC_IDMAC_DES0_DIC bit prevents the DMA from sending an interrupt
+	 * after it has finished this reinitialization.
+	 */
+	pdes[i - 1].config = SDXC_IDMAC_DES0_OWN;
+	pdes[i - 1].config |= SDXC_IDMAC_DES0_FD;
+	pdes[i - 1].config |= SDXC_IDMAC_DES0_LD;
+	pdes[i - 1].config &= ~SDXC_IDMAC_DES0_DIC;
 
 	/*
 	 * Avoid the io-store starting the idmac hitting io-mem before the