Patch "tty/serial: at91: maxburst was missing for dma transfers" has been added to the 4.0-stable tree

Patch "tty/serial: at91: maxburst was missing for dma transfers" has been added to the 4.0-stable tree

[gregkh]

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

    tty/serial: at91: maxburst was missing for dma transfers

to the 4.0-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:
     tty-serial-at91-maxburst-was-missing-for-dma-transfers.patch
and it can be found in the queue-4.0 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 a8d4e01637902311c5643b69a5c80e2805f04054 Mon Sep 17 00:00:00 2001
From: Ludovic Desroches <ludovic.desroches@atmel.com>
Date: Thu, 16 Apr 2015 16:58:12 +0200
Subject: tty/serial: at91: maxburst was missing for dma transfers

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

commit a8d4e01637902311c5643b69a5c80e2805f04054 upstream.

Maxburst was not set when doing the dma slave configuration. This value
is checked by the recently introduced xdmac. It causes an error when
doing the slave configuration and so prevents from using dma.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/tty/serial/atmel_serial.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -880,6 +880,7 @@ static int atmel_prepare_tx_dma(struct u
 	config.direction = DMA_MEM_TO_DEV;
 	config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 	config.dst_addr = port->mapbase + ATMEL_US_THR;
+	config.dst_maxburst = 1;
 
 	ret = dmaengine_slave_config(atmel_port->chan_tx,
 				     &config);
@@ -1059,6 +1060,7 @@ static int atmel_prepare_rx_dma(struct u
 	config.direction = DMA_DEV_TO_MEM;
 	config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 	config.src_addr = port->mapbase + ATMEL_US_RHR;
+	config.src_maxburst = 1;
 
 	ret = dmaengine_slave_config(atmel_port->chan_rx,
 				     &config);


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

queue-4.0/tty-serial-at91-maxburst-was-missing-for-dma-transfers.patch