Patch "usb: musb: fix DMA for host mode" has been added to the 4.4-stable tree

Patch "usb: musb: fix DMA for host mode" has been added to the 4.4-stable tree

[gregkh]

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

    usb: musb: fix DMA for host mode

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:
     usb-musb-fix-dma-for-host-mode.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@vger.kernel.org> know about it.


>From 4c2ba0c67394514f3f75c660c9f5d02e66a7efd4 Mon Sep 17 00:00:00 2001
From: Cristian Birsan <cristian.birsan@microchip.com>
Date: Fri, 19 Feb 2016 10:11:56 +0200
Subject: usb: musb: fix DMA for host mode

From: Cristian Birsan <cristian.birsan@microchip.com>

commit 4c2ba0c67394514f3f75c660c9f5d02e66a7efd4 upstream.

Commit ac33cdb16681 ("usb: musb: Remove ifdefs for musb_host_rx in
musb_host.c part5") introduces a problem setting DMA host mode.

The musb_advance_schedule() is called immediately after receiving an
endpoint RX interrupt without waiting for the DMA transfer to complete.

As a consequence when the dma complete interrupt arrives the in_qh
member of hw_ep is already null an the musb_host_rx() exits on !urb
error case. Fix the done condition that advances the musb schedule.

Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: Joshua Henderson <joshua.henderson@microchip.com>
Tested-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Adam Ford <aford173@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/musb/musb_host.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -2008,10 +2008,8 @@ void musb_host_rx(struct musb *musb, u8
 				qh->offset,
 				urb->transfer_buffer_length);
 
-			done = musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh,
-							      urb, xfer_len,
-							      iso_err);
-			if (done)
+			if (musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh, urb,
+							   xfer_len, iso_err))
 				goto finish;
 			else
 				dev_err(musb->controller, "error: rx_dma failed\n");


Patches currently in stable-queue which might be from cristian.birsan@microchip.com are

queue-4.4/usb-musb-fix-dma-for-host-mode.patch
queue-4.4/usb-musb-fix-dma-desired-mode-for-mentor-dma-engine.patch