linux/drivers/input
Dmitry Torokhov e9fb7cc638 Input: psmouse - disable automatic probing of BYD touchpads
BYD automatic protocol detection is extremely unreliable and is often
triggers false positives on regular mice, Sentelic touchpads, and other
devices. BYD has several documents that have recommended detection
sequence, but they conflict with each other and, as far as I can see, still
would not produce unique enough output to reliably differentiate BYD from
other PS/2 devices.

OEMs sourcing BYD devices also do not do us any favors by not supplying any
reasonable DMI data and instead leaving turds like "To Be Filled By O.E.M."
in place of vendor data, or "System Serial Number" as serial number.

On top of that BYD is not truly modern multitouch controller, but rather a
single-touch transitional device that only reports absolute coordinates at
the beginning of finger contact and then reverts to reporting
displacements, and thus not very precise; the only benefit from using BYD
mode vs the legacy PS/2 mode is possibility of edge scrolling.

Given the above, and the fact that BYD devices are somewhat uncommon, let's
disable automatic detection of BYD devices. Users who know they have BYD
trackpads or want to experiment can attempt to activate BYD protocol via
sysfs:

	echo -n "byd" > /sys/bus/serio/devices/serio1/drvctl

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=151691
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=175421
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=120781
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=121281
Fixes: 98ee377144 ("Input: byd - add BYD PS/2 touchpad driver")
Cc: stable@vger.kernel.org # 4.6+
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2016-11-16 17:25:31 -08:00
..
gameport x86/asm/tsc: Rename native_read_tsc() to rdtsc() 2015-07-06 15:23:28 +02:00
joystick Input: xpad - power off wireless 360 controllers on suspend 2016-07-27 18:26:09 -07:00
keyboard Merge branch 'next' into for-linus 2016-10-03 16:42:21 -07:00
misc Input: tps65218-pwrbutton - add support for tps65217 variant 2016-09-10 10:47:49 -07:00
mouse Input: psmouse - disable automatic probing of BYD touchpads 2016-11-16 17:25:31 -08:00
rmi4 Merge branch 'next' into for-linus 2016-10-13 17:23:40 -07:00
serio Input: i8042 - add XMG C504 to keyboard reset table 2016-10-19 12:10:04 -07:00
tablet Input: pegasus_notetaker - directly include workqueue header 2016-08-25 10:11:32 -07:00
touchscreen Merge branch 'next' into for-linus 2016-10-13 17:23:40 -07:00
apm-power.c
evbug.c
evdev.c Input: evdev - fix bug in checking duplicate clock change request 2015-10-31 10:35:02 -07:00
ff-core.c Input: document and check on implicitly defined FF_MAX_EFFECTS 2015-10-16 15:32:16 -07:00
ff-memless.c [media] fixp-arith: replace sin/cos table by a better precision one 2015-03-02 14:50:06 -03:00
input-compat.c drivers/input: eliminate INPUT_COMPAT_TEST macro 2016-03-25 16:37:42 -07:00
input-compat.h drivers/input: eliminate INPUT_COMPAT_TEST macro 2016-03-25 16:37:42 -07:00
input-leds.c Input: LEDs - skip unnamed LEDs 2015-07-24 09:11:01 -07:00
input-mt.c Input: update input_mt_report_pointer_emulation to support hovering 2016-06-01 14:21:10 -07:00
input-polldev.c Input: implement managed polled input devices 2014-05-14 16:40:04 -07:00
input.c Merge branch 'for-linus' into next 2016-07-19 11:02:56 -07:00
joydev.c Input: joydev - recognize devices with Z axis as joysticks 2016-09-26 20:03:06 -07:00
Kconfig Input: synaptics-rmi4 - add support for Synaptics RMI4 devices 2016-03-10 16:02:39 -08:00
Makefile Input: synaptics-rmi4 - add support for Synaptics RMI4 devices 2016-03-10 16:02:39 -08:00
matrix-keymap.c
mousedev.c Input: mousedev - fix race when creating mixed device 2014-03-29 14:44:23 -07:00
sparse-keymap.c treewide: Fix typo in Documentation/DocBook 2014-02-19 14:58:17 +01:00