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From 86da2d12cf6f76b1fa487f7acf3995f058a2e516 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Fri, 1 Aug 2014 17:27:49 +0200
Subject: [PATCH v2 1/2] uas: Limit qdepth to 32 when connected over usb-2

Some jmicron uas chipsets act up (they disconnect from the bus) when sending
more then 32 commands to them at once.

Rather then building an ever growing list with usb-id based quirks for
devices using this chipset, simply reduce the qdepth to 32 when connected
over usb-2. 32 should be plenty to keep things close to maximum
possible throughput on usb-2.

Cc: stable@vger.kernel.org
Tested-and-reported-by: Laszlo T. <tlacix@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/usb/storage/uas.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index 511b229..3f42785 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -1026,7 +1026,7 @@ static int uas_configure_endpoints(struct uas_dev_info *devinfo)
 					    usb_endpoint_num(&eps[3]->desc));
 
 	if (udev->speed != USB_SPEED_SUPER) {
-		devinfo->qdepth = 256;
+		devinfo->qdepth = 32;
 		devinfo->use_streams = 0;
 	} else {
 		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
-- 
2.0.4