[3.16.y-ckt stable] Patch "HID: core: do not scan reports if the group is already set" has been added to the 3.16.y-ckt tree

[Luis Henriques]

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

    HID: core: do not scan reports if the group is already set

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt27.

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

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

---8<------------------------------------------------------------

>From f2ff715b6077e0dcdcceb511fdcb0d7f8e77eac8 Mon Sep 17 00:00:00 2001
From: Benjamin Tissoires <benjamin.tissoires at redhat.com>
Date: Tue, 30 Sep 2014 13:18:24 -0400
Subject: HID: core: do not scan reports if the group is already set

commit 9578f41aeaee5010384f4f8484da1566e2ce4901 upstream.

This allows the transport layer (I have in mind hid-logitech-dj and uhid)
to set the group before it is added to the hid bus. This way, it can
bypass the hid_scan_report() call, and choose in advance which driver
will handle the newly created hid device.

Signed-off-by: Benjamin Tisssoires <benjamin.tissoires at redhat.com>
Signed-off-by: Jiri Kosina <jkosina at suse.cz>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/hid/hid-core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index fb16c812816a..814449b80201 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -2531,7 +2531,8 @@ int hid_add_device(struct hid_device *hdev)
 	 * Scan generic devices for group information
 	 */
 	if (hid_ignore_special_drivers ||
-	    !hid_match_id(hdev, hid_have_special_driver)) {
+	    (!hdev->group &&
+	     !hid_match_id(hdev, hid_have_special_driver))) {
 		ret = hid_scan_report(hdev);
 		if (ret)
 			hid_warn(hdev, "bad device descriptor (%d)\n", ret);