[Natty][SRU][PATCH 1/1] usbnet/cdc_ncm: add missing .reset_resume hook

[Leann Ogasawara]

BugLink: http://bugs.launchpad.net/bugs/793892

SRU Justification:

Impact: The cdc_ncm module, which provides support for the Ericsson
F5521gw Mobile Broadband Modem, unregisters the device after suspend
because the .reset_resume hook in the driver is not assigned.

Fix: Upstream commit 85e3c65fa3a1d0542c18151

Test Case: Without the fix, after resume from suspend you'll notice
messages similar to the following in dmesg output:

cdc_ncm 2-1.4:1.6: no reset_resume for driver cdc_ncm?
cdc_ncm 2-1.4:1.7: no reset_resume for driver cdc_ncm?
cdc_ncm 2-1.4:1.6: usb0: unregister 'cdc_ncm' usb-0000:00:1d.0-1.4, CDC NCM

The patch author, who is also the LP bug reporter, submitted this to
upstream 2.6.38.y but was unfortunately told there will be no further
2.6.38.y releases:  

http://marc.info/?l=linux-usb&m=130737305305181&w=2

I've built a test kernel with the patch applied and have confirmation it
resolves the issue.  Please consider for Natty SRU.  Note the only
reason it is not a clean cherry-pick is due to the DRIVER_VERSION
string.

Thanks,
Leann

The following changes since commit f3fd91d6053b0fc7d37815d2830495ffe5c6b06e:
  Tim Gardner (1):
        UBUNTU: Start new release

are available in the git repository at:

  git://kernel.ubuntu.com/ogasawara/ubuntu-natty.git lp793892

Stefan Metzmacher (1):
      usbnet/cdc_ncm: add missing .reset_resume hook

 drivers/net/usb/cdc_ncm.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

>From 9a5ebc5a7ace79a8683f6ac0d10d154d21e73b4d Mon Sep 17 00:00:00 2001
From: Stefan Metzmacher <metze at samba.org>
Date: Wed, 1 Jun 2011 02:01:41 +0000
Subject: [PATCH] usbnet/cdc_ncm: add missing .reset_resume hook

BugLink: http://bugs.launchpad.net/bugs/793892

This avoids messages like this after suspend:

   cdc_ncm 2-1.4:1.6: no reset_resume for driver cdc_ncm?
   cdc_ncm 2-1.4:1.7: no reset_resume for driver cdc_ncm?
   cdc_ncm 2-1.4:1.6: usb0: unregister 'cdc_ncm' usb-0000:00:1d.0-1.4, CDC NCM

This is important for the Ericsson F5521gw GSM/UMTS modem.
Otherwise modemmanager looses the fact that the cdc_ncm and cdc_acm devices
belong together.

The cdc_ether module does the same.

Signed-off-by: Stefan Metzmacher <metze at samba.org>
Signed-off-by: David S. Miller <davem at davemloft.net>

(backport from commit 85e3c65fa3a1d0542c18151 upstream)
Signed-off-by: Leann Ogasawara <leann.ogasawara at canonical.com>
---
 drivers/net/usb/cdc_ncm.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 7113168..9d78fe6 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -54,7 +54,7 @@
 #include <linux/usb/usbnet.h>
 #include <linux/usb/cdc.h>
 
-#define	DRIVER_VERSION				"7-Feb-2011"
+#define	DRIVER_VERSION				"01-June-2011"
 
 /* CDC NCM subclass 3.2.1 */
 #define USB_CDC_NCM_NDP16_LENGTH_MIN		0x10
@@ -1254,6 +1254,7 @@ static struct usb_driver cdc_ncm_driver = {
 	.disconnect = cdc_ncm_disconnect,
 	.suspend = usbnet_suspend,
 	.resume = usbnet_resume,
+	.reset_resume =	usbnet_resume,
 	.supports_autosuspend = 1,
 };
 
-- 
1.7.0.4