[PATCH] dmaengine: fsldma: set BWC, DAHTS and SAHTS values correctly

From: Thomas Breitung
Date: Mon Jun 19 2017 - 10:49:38 EST


The bits of BWC, DAHTS and SAHTS in the DMA mode register must be cleared
before a new value can be or-ed in.

Signed-off-by: Thomas Breitung <thomas.breitung@xxxxxxxxxxx>
Signed-off-by: Wolfgang Ocker <weo@xxxxxxxxxxxx>
---
drivers/dma/fsldma.c | 5 ++++-
drivers/dma/fsldma.h | 4 ++++
2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index 51c75bf2b9b6..3b8b752ede2d 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -269,6 +269,7 @@ static void fsl_chan_set_src_loop_size(struct fsldma_chan *chan, int size)
case 2:
case 4:
case 8:
+ mode &= ~FSL_DMA_MR_SAHTS_MASK;
mode |= FSL_DMA_MR_SAHE | (__ilog2(size) << 14);
break;
}
@@ -301,6 +302,7 @@ static void fsl_chan_set_dst_loop_size(struct fsldma_chan *chan, int size)
case 2:
case 4:
case 8:
+ mode &= ~FSL_DMA_MR_DAHTS_MASK;
mode |= FSL_DMA_MR_DAHE | (__ilog2(size) << 16);
break;
}
@@ -327,7 +329,8 @@ static void fsl_chan_set_request_count(struct fsldma_chan *chan, int size)
BUG_ON(size > 1024);

mode = get_mr(chan);
- mode |= (__ilog2(size) << 24) & 0x0f000000;
+ mode &= ~FSL_DMA_MR_BWC_MASK;
+ mode |= (__ilog2(size) << 24) & FSL_DMA_MR_BWC_MASK;

set_mr(chan, mode);
}
diff --git a/drivers/dma/fsldma.h b/drivers/dma/fsldma.h
index 31bffccdcc75..4787d485dd76 100644
--- a/drivers/dma/fsldma.h
+++ b/drivers/dma/fsldma.h
@@ -36,6 +36,10 @@
#define FSL_DMA_MR_DAHE 0x00002000
#define FSL_DMA_MR_SAHE 0x00001000

+#define FSL_DMA_MR_SAHTS_MASK 0x0000C000
+#define FSL_DMA_MR_DAHTS_MASK 0x00030000
+#define FSL_DMA_MR_BWC_MASK 0x0f000000
+
/*
* Bandwidth/pause control determines how many bytes a given
* channel is allowed to transfer before the DMA engine pauses
--
2.13.0