Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

dmaengine: at_xdmac: fix bug in prep_dma_cyclic

Browse source 
In cyclic mode, the round chaining has been broken by the introduction
of at_xdmac_queue_desc(): AT_XDMAC_MBR_UBC_NDE is set for all descriptors
excepted for the last one. at_xdmac_queue_desc() has to be called one
more time to chain the last and the first descriptors.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: 0d0ee751f7 ("dmaengine: xdmac: Rework the chaining logic")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Ludovic Desroches 2015-07-22 16:12:29 +02:00 committed by Vinod Koul
parent ae9c02b421
commit e900c30dc1
1 changed files with 1 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
drivers/dma/at_xdmac.c
View file

@ -795,10 +795,7 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
list_add_tail(&desc->desc_node, &first->descs_list);
}
prev->lld.mbr_nda = first->tx_dma_desc.phys;
dev_dbg(chan2dev(chan),
"%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
__func__, prev, &prev->lld.mbr_nda);
at_xdmac_queue_desc(chan, prev, first);
first->tx_dma_desc.flags = flags;
first->xfer_size = buf_len;
first->direction = direction;