Patch "dmaengine: at_xdmac: fix bug in prep_dma_cyclic" has been added to the 4.2-stable tree

Patch "dmaengine: at_xdmac: fix bug in prep_dma_cyclic" has been added to the 4.2-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    dmaengine: at_xdmac: fix bug in prep_dma_cyclic

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     dmaengine-at_xdmac-fix-bug-in-prep_dma_cyclic.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From e900c30dc1bb0cbc07708e9be1188f531632b2ef Mon Sep 17 00:00:00 2001
From: Ludovic Desroches <ludovic.desroches@atmel.com>
Date: Wed, 22 Jul 2015 16:12:29 +0200
Subject: dmaengine: at_xdmac: fix bug in prep_dma_cyclic

From: Ludovic Desroches <ludovic.desroches@atmel.com>

commit e900c30dc1bb0cbc07708e9be1188f531632b2ef upstream.

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: 0d0ee751f7f7 ("dmaengine: xdmac: Rework the chaining logic")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/dma/at_xdmac.c |    5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -806,10 +806,7 @@ at_xdmac_prep_dma_cyclic(struct dma_chan
 		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;


Patches currently in stable-queue which might be from ludovic.desroches@atmel.com are

queue-4.2/dmaengine-at_xdmac-clean-used-descriptor.patch
queue-4.2/dmaengine-at_xdmac-change-block-increment-addressing-mode.patch
queue-4.2/dmaengine-at_xdmac-fix-bug-in-prep_dma_cyclic.patch