lkml.org 
[lkml]   [2016]   [Mar]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v3 06/15] dmaengine: dw: clear LLP_[SD]_EN bits in last descriptor of a chain
Date
From: Mans Rullgard <mans@mansr.com>

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>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.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 7cbc2a9..4ac12ee 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -759,6 +759,7 @@ 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;

@@ -919,6 +920,7 @@ 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
\
 
 \ /
  Last update: 2016-03-18 16:01    [W:0.163 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site