[PATCH 3.5 08/96] HID: Bump maximum global item tag report size to 128 bytes

[Luis Henriques]

3.5.7.29 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Marek Vasut <marex at denx.de>

commit 23408f95fa92483527de3206ebeb55c37e0f679c upstream.

The Freescale i.MX28 BootROM USB recovery mode implements the USB HID
protocol, yet the global item tag report size is 128. Linux checks if
this is 96 as of now, see [1]. This causes Linux to refuse to communicate
with this device, making it impossible to use the recovery mode.

This is not a standard HID device per se, but rather a software emulation
implemented within the BootROM code and realized through USB OTG-capable
port switched to device mode present on the device.

Previous attempt to discuss this issue dates back to 2011, see [2]. There
has been not much response. Also noteworthy is the [3], where there seems
to be a pointing device that has issue similar to this one.

The tool making use of the USB recovery mode is available at [4].

[1] http://comments.gmane.org/gmane.linux.kernel.input/22328
[2] http://www.spinics.net/lists/linux-usb/msg43463.html
[3] https://bbs.archlinux.org/viewtopic.php?pid=1141340
[4] http://git.bfuser.eu/?p=marex/mxsldr.git;a=summary

Signed-off-by: Marek Vasut <marex at denx.de>
Cc: Chen Peter <B29397 at freescale.com>
Cc: Greg KH <greg at kroah.com>
Cc: Jiri Kosina <jkosina at suse.cz>
Signed-off-by: Jiri Kosina <jkosina at suse.cz>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/hid/hid-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 509d119..abc1fcd 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -382,7 +382,7 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
 
 	case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
 		parser->global.report_size = item_udata(item);
-		if (parser->global.report_size > 96) {
+		if (parser->global.report_size > 128) {
 			hid_err(parser->device, "invalid report_size %d\n",
 					parser->global.report_size);
 			return -1;
-- 
1.8.3.2