This is a note to let you know that I've just added the patch titled
dmaengine: ep93xx: Always start from BASE0
to the 4.4-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-ep93xx-always-start-from-base0.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0037ae47812b1f431cc602100d1d51f37d77b61e Mon Sep 17 00:00:00 2001
From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
Date: Mon, 22 May 2017 16:05:22 +0200
Subject: dmaengine: ep93xx: Always start from BASE0
From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
commit 0037ae47812b1f431cc602100d1d51f37d77b61e upstream.
The current buffer is being reset to zero on device_free_chan_resources()
but not on device_terminate_all(). It could happen that HW is restarted and
expects BASE0 to be used, but the driver is not synchronized and will start
from BASE1. One solution is to reset the buffer explicitly in
m2p_hw_setup().
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dma/ep93xx_dma.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/dma/ep93xx_dma.c
+++ b/drivers/dma/ep93xx_dma.c
@@ -325,6 +325,8 @@ static int m2p_hw_setup(struct ep93xx_dm
| M2P_CONTROL_ENABLE;
m2p_set_control(edmac, control);
+ edmac->buffer = 0;
+
return 0;
}
Patches currently in stable-queue which might be from alexander.sverdlin@xxxxxxxxx are
queue-4.4/dmaengine-ep93xx-always-start-from-base0.patch
queue-4.4/dmaengine-ep93xx-don-t-drain-the-transfers-in-terminate_all.patch