HID: core: check whether Usage Page item is after Usage ID items
authorCandle Sun <candle.sun@unisoc.com>
Tue, 22 Oct 2019 14:21:39 +0000 (22:21 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 5 Dec 2019 14:38:29 +0000 (15:38 +0100)
commit564262cf4274a238a124fa76e48f14ead06caac2
tree3a58b57b94be8a50399d85bf5072412c96f80d96
parent61fa9f167caaa73d0a7c88f498eceeb12c6fa3db
HID: core: check whether Usage Page item is after Usage ID items

commit 1cb0d2aee26335d0bccf29100c7bed00ebece851 upstream.

Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation
to Main item") adds support for Usage Page item after Usage ID items
(such as keyboards manufactured by Primax).

Usage Page concatenation in Main item works well for following report
descriptor patterns:

    USAGE_PAGE (Keyboard)                   05 07
    USAGE_MINIMUM (Keyboard LeftControl)    19 E0
    USAGE_MAXIMUM (Keyboard Right GUI)      29 E7
    LOGICAL_MINIMUM (0)                     15 00
    LOGICAL_MAXIMUM (1)                     25 01
    REPORT_SIZE (1)                         75 01
    REPORT_COUNT (8)                        95 08
    INPUT (Data,Var,Abs)                    81 02

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

    USAGE_MINIMUM (Keyboard LeftControl)    19 E0
    USAGE_MAXIMUM (Keyboard Right GUI)      29 E7
    LOGICAL_MINIMUM (0)                     15 00
    LOGICAL_MAXIMUM (1)                     25 01
    REPORT_SIZE (1)                         75 01
    REPORT_COUNT (8)                        95 08
    USAGE_PAGE (Keyboard)                   05 07
    INPUT (Data,Var,Abs)                    81 02

But it makes the parser act wrong for the following report
descriptor pattern(such as some Gamepads):

    USAGE_PAGE (Button)                     05 09
    USAGE (Button 1)                        09 01
    USAGE (Button 2)                        09 02
    USAGE (Button 4)                        09 04
    USAGE (Button 5)                        09 05
    USAGE (Button 7)                        09 07
    USAGE (Button 8)                        09 08
    USAGE (Button 14)                       09 0E
    USAGE (Button 15)                       09 0F
    USAGE (Button 13)                       09 0D
    USAGE_PAGE (Consumer Devices)           05 0C
    USAGE (Back)                            0a 24 02
    USAGE (HomePage)                        0a 23 02
    LOGICAL_MINIMUM (0)                     15 00
    LOGICAL_MAXIMUM (1)                     25 01
    REPORT_SIZE (1)                         75 01
    REPORT_COUNT (11)                       95 0B
    INPUT (Data,Var,Abs)                    81 02

With Usage Page concatenation in Main item, parser recognizes all the
11 Usages as consumer keys, it is not the HID device's real intention.

This patch checks whether Usage Page is really defined after Usage ID
items by comparing usage page using status.

Usage Page concatenation on currently defined Usage Page will always
do in local parsing when Usage ID items encountered.

When Main item is parsing, concatenation will do again with last
defined Usage Page if this page has not been used in the previous
usages concatenation.

Signed-off-by: Candle Sun <candle.sun@unisoc.com>
Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Siarhei Vishniakou <svv@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/hid/hid-core.c