Input: cros_ec_keyb - fix button/switch capability reports
authorBrian Norris <briannorris@chromium.org>
Mon, 12 Nov 2018 19:23:39 +0000 (11:23 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 8 Dec 2018 12:03:39 +0000 (13:03 +0100)
commit4121029c4311c4e6298fc601bcb6b7dd2167b415
tree06757afcee94c482c6071fce64973be846d32112
parent58a3a4e82dea339ef011ff2510c11e21bc53e418
Input: cros_ec_keyb - fix button/switch capability reports

commit ac5722c1643a2fb75224c79b578214956d34f989 upstream.

The cros_ec_keyb_bs array lists buttons and switches together, expecting
that its users will match the appropriate type and bit fields. But
cros_ec_keyb_register_bs() only checks the 'bit' field, which causes
misreported input capabilities in some cases. For example, tablets
(e.g., Scarlet -- a.k.a. Acer Chromebook Tab 10) were reporting a SW_LID
capability, because EC_MKBP_POWER_BUTTON and EC_MKBP_LID_OPEN happen to
share the same bit.

(This has comedic effect on a tablet, in which a power-management daemon
then thinks this "lid" is closed, and so puts the system to sleep as
soon as it boots!)

To fix this, check both the 'ev_type' and 'bit' fields before reporting
the capability.

Tested with a lid (Kevin / Samsung Chromebook Plus) and without a lid
(Scarlet / Acer Chromebook Tab 10).

This error got introduced when porting the feature from the downstream
Chromium OS kernel to be upstreamed.

Fixes: cdd7950e7aa4 ("input: cros_ec_keyb: Add non-matrix buttons and switches")
Cc: <stable@vger.kernel.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/input/keyboard/cros_ec_keyb.c