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Subject[PATCH 3/4] mmc: sunxi: Reset behavior fix
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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@o2s.ch>
Reported-by: 李想 <lixiang@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


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