[3.5.y.z extended stable] Patch "usb: Add device quirk for Logitech HD Pro Webcams C920 and C930e" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    usb: Add device quirk for Logitech HD Pro Webcams C920 and C930e

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 719a1b33388aa0f3c5285901a54f8eddec390875 Mon Sep 17 00:00:00 2001
From: Julius Werner <jwerner at chromium.org>
Date: Tue, 4 Mar 2014 10:52:39 -0800
Subject: usb: Add device quirk for Logitech HD Pro Webcams C920 and C930e

commit e0429362ab15c46ea4d64c3f8c9e0933e48a143a upstream.

We've encountered a rare issue when enumerating two Logitech webcams
after a reboot that doesn't power cycle the USB ports. They are spewing
random data (possibly some leftover UVC buffers) on the second
(full-sized) Get Configuration request of the enumeration phase. Since
the data is random this can potentially cause all kinds of odd behavior,
and since it occasionally happens multiple times (after the kernel
issues another reset due to the garbled configuration descriptor), it is
not always recoverable. Set the USB_DELAY_INIT quirk that seems to work
around the issue.

Signed-off-by: Julius Werner <jwerner at chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
[ luis: backported to 3.5: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/usb/core/quirks.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 987d3ef..a5545de 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -41,6 +41,10 @@ static const struct usb_device_id usb_quirk_list[] = {
 	/* Microsoft LifeCam-VX700 v2.0 */
 	{ USB_DEVICE(0x045e, 0x0770), .driver_info = USB_QUIRK_RESET_RESUME },

+	/* Logitech HD Pro Webcams C920 and C930e */
+	{ USB_DEVICE(0x046d, 0x082d), .driver_info = USB_QUIRK_DELAY_INIT },
+	{ USB_DEVICE(0x046d, 0x0843), .driver_info = USB_QUIRK_DELAY_INIT },
+
 	/* Logitech Webcam C200 */
 	{ USB_DEVICE(0x046d, 0x0802), .driver_info = USB_QUIRK_RESET_RESUME },

--
1.9.0