[PATCH v3 3/3] dmaengine: qcom: bam_dma: add command descriptor flag

From: Abhishek Sahu
Date: Tue Aug 01 2017 - 10:12:16 EST


If DMA_PREP_CMD flag is passed in prep_slave_sg then peripheral
driver has passed the data is in BAM command descriptor format
and BAM driver should set CMD bit for each of the HW descriptors.

Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx>
---
drivers/dma/qcom/bam_dma.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index 03c4eb3..6d89fb6 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -65,6 +65,7 @@ struct bam_desc_hw {
#define DESC_FLAG_EOT BIT(14)
#define DESC_FLAG_EOB BIT(13)
#define DESC_FLAG_NWD BIT(12)
+#define DESC_FLAG_CMD BIT(11)

struct bam_async_desc {
struct virt_dma_desc vd;
@@ -645,6 +646,9 @@ static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
unsigned int curr_offset = 0;

do {
+ if (flags & DMA_PREP_CMD)
+ desc->flags |= cpu_to_le16(DESC_FLAG_CMD);
+
desc->addr = cpu_to_le32(sg_dma_address(sg) +
curr_offset);

@@ -960,7 +964,7 @@ static void bam_start_dma(struct bam_chan *bchan)

/* set any special flags on the last descriptor */
if (async_desc->num_desc == async_desc->xfer_len)
- desc[async_desc->xfer_len - 1].flags =
+ desc[async_desc->xfer_len - 1].flags |=
cpu_to_le16(async_desc->flags);
else
desc[async_desc->xfer_len - 1].flags |=
--
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