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

    xhci: correct burst count field for isoc transfers on 1.0 xhci hosts

to the 3.4-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:
     xhci-correct-burst-count-field-for-isoc-transfers-on-1.0-xhci-hosts.patch
and it can be found in the queue-3.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 3213b151387df0b95f4eada104f68eb1c1409cb3 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <[email protected]>
Date: Tue, 24 Jun 2014 17:14:41 +0300
Subject: xhci: correct burst count field for isoc transfers on 1.0 xhci hosts

From: Mathias Nyman <[email protected]>

commit 3213b151387df0b95f4eada104f68eb1c1409cb3 upstream.

The transfer burst count (TBC) field in xhci 1.0 hosts should be set
to the number of bursts needed to transfer all packets in a isoc TD.
Supported values are 0-2 (1 to 3 bursts per service interval).

Formula for TBC calculation is given in xhci spec section 4.11.2.3:
TBC = roundup( Transfer Descriptor Packet Count / Max Burst Size +1 ) - 1

This patch should be applied to stable kernels since 3.0 that contain
the commit 5cd43e33b9519143f06f507dd7cbee6b7a621885
"xhci 1.0: Set transfer burst count field."

Suggested-by: ShiChun Ma <[email protected]>
Signed-off-by: Mathias Nyman <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/usb/host/xhci-ring.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3588,7 +3588,7 @@ static unsigned int xhci_get_burst_count
                return 0;
 
        max_burst = urb->ep->ss_ep_comp.bMaxBurst;
-       return roundup(total_packet_count, max_burst + 1) - 1;
+       return DIV_ROUND_UP(total_packet_count, max_burst + 1) - 1;
 }
 
 /*


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.4/xhci-fix-runtime-suspended-xhci-from-blocking-system-suspend.patch
queue-3.4/xhci-correct-burst-count-field-for-isoc-transfers-on-1.0-xhci-hosts.patch
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