Messages in this thread Patch in this message | | | From | Mans Rullgard <> | Subject | [PATCH 02/15] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain | Date | Sun, 24 Jan 2016 19:21:49 +0000 |
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The datasheet requires that the LLP_[SD]_EN bits be cleared whenever LLP.LOC is zero, i.e. in the last descriptor of a multi-block chain. Make the driver do this.
Signed-off-by: Mans Rullgard <mans@mansr.com> --- drivers/dma/dw/core.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index cc7c1acc8188..03ec88f1c161 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -764,6 +764,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, lli_set(prev, ctllo, DWC_CTLL_INT_EN); prev->lli.llp = 0; + lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); first->txd.flags = flags; first->total_len = len; @@ -923,6 +924,7 @@ slave_sg_fromdev_fill_desc: lli_set(prev, ctllo, DWC_CTLL_INT_EN); prev->lli.llp = 0; + lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); first->total_len = total_len; return &first->txd; -- 2.7.0
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