[PATCH 2/7] dmaengine: sprd: Get transfer residue depending on the transfer direction

Baolin Wang
2018-09-29T05:50:08Z

Add one field to save the transfer direction for struct sprd_dma_desc,
which is used to get correct transfer residue depending on the transfer
direction.

[Baolin Wang adds one field to present the transfer direction]
Signed-off-by: Eric Long <eric.long@spreadtrum.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
drivers/dma/sprd-dma.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index c226dc93..4f3587b 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -159,6 +159,7 @@ struct sprd_dma_chn_hw {
struct sprd_dma_desc {
struct virt_dma_desc vd;
struct sprd_dma_chn_hw chn_hw;
+ enum dma_transfer_direction dir;
};

/* dma channel description */
@@ -331,6 +332,17 @@ static void sprd_dma_stop_and_disable(struct sprd_dma_chn *schan)
sprd_dma_disable_chn(schan);
}

+static unsigned long sprd_dma_get_src_addr(struct sprd_dma_chn *schan)
+{
+ unsigned long addr, addr_high;
+
+ addr = readl(schan->chn_base + SPRD_DMA_CHN_SRC_ADDR);
+ addr_high = readl(schan->chn_base + SPRD_DMA_CHN_WARP_PTR) &
+ SPRD_DMA_HIGH_ADDR_MASK;
+
+ return addr | (addr_high << SPRD_DMA_HIGH_ADDR_OFFSET);
+}
+
static unsigned long sprd_dma_get_dst_addr(struct sprd_dma_chn *schan)
{
unsigned long addr, addr_high;
@@ -534,7 +546,12 @@ static enum dma_status sprd_dma_tx_status(struct dma_chan *chan,
else
pos = 0;
} else if (schan->cur_desc && schan->cur_desc->vd.tx.cookie == cookie) {
- pos = sprd_dma_get_dst_addr(schan);
+ struct sprd_dma_desc *sdesc = to_sprd_dma_desc(vd);
+
+ if (sdesc->dir == DMA_DEV_TO_MEM)
+ pos = sprd_dma_get_dst_addr(schan);
+ else
+ pos = sprd_dma_get_src_addr(schan);
} else {
pos = 0;
}
@@ -804,6 +821,8 @@ static int sprd_dma_fill_linklist_desc(struct dma_chan *chan,
if (!sdesc)
return NULL;

+ sdesc->dir = dir;
+
for_each_sg(sgl, sg, sglen, i) {
len = sg_dma_len(sg);

--
1.7.9.5