Commit 23408f95 authored Aug 05, 2012 by Marek Vasut Committed by Jiri Kosina Aug 15, 2012

HID: Bump maximum global item tag report size to 128 bytes

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@denx.de>
Cc: Chen Peter <B29397@freescale.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

parent e8ff13b0

drivers/hid/hid-core.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -374,7 +374,7 @@ 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;

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