linux.git/drivers/input/mouse/alps.c, branch v3.18.22

Input: alps - v7: fix finger counting for > 2 fingers on clickpads

2015-01-16T14:59:55+00:00

commit d27eb7931c98a1ebfc9b2fcc48939846bcbfc804 upstream.

Protocol v7 uses the middle / right button bits on clickpads to communicate
"location" information of a 3th touch (and possible 4th) touch on
clickpads.

Specifically when 3 touches are down, if one of the 3 touches is in the
left / right button area, this will get reported in the middle / right
button bits and the touchpad will still send a TWO type packet rather then
a MULTI type packet, so when this happens we must add the finger reported
in the button area to the finger count.

Likewise we must also add fingers reported this way to the finger count
when we get MULTI packets.

BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=86338
Signed-off-by: Hans de Goede 
Tested-by: Benjamin Tissoires 
Signed-off-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

Input: alps - v7: sometimes a single touch is reported in mt[1]

2015-01-16T14:59:55+00:00

commit 7091c443dda8c6c6d8e70e33452252f9ad3e7814 upstream.

The v7 proto differentiates between a primary touch (with high precision)
and a secondary touch (with lower precision). Normally when 2 fingers are
down and one is lifted the still present touch becomes the primary touch,
but some traces have shown that this does not happen always.

This commit deals with this by making alps_get_mt_count() not stop at the
first empty mt slot, and if a touch is present in mt[1] and not mt[0]
moving the data to mt[0] (for input_mt_assign_slots).

BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=86338
Signed-off-by: Hans de Goede 
Tested-by: Benjamin Tissoires 
Signed-off-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

Input: alps - v7: ignore new packets

2015-01-16T14:59:55+00:00

commit 8b23811535d2e1dd6abbe4ce6ea1edfd50ce72de upstream.

NEW packets are send to indicate a discontinuity in the finger coordinate
reporting. Specifically a finger may have moved from slot 0 to 1 or vice
versa.  INPUT_MT_TRACK takes care of this for us.

NEW packets have 3 problems:
1) They do not contain middle / right button info (on non clickpads)
   this can be worked around by preserving the old button state
2) They do not contain an accurate fingercount, and they are
   typically send when the number of fingers changes. We cannot use
   the old finger count as that may mismatch with the amount of
   touch coordinates we've available in the NEW packet
3) Their x data for the second touch is inaccurate leading to
   a possible jump of the x coordinate by 16 units when the first
   non NEW packet comes in

Since problems 2 & 3 cannot be worked around, just ignore them.

BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=86338
Signed-off-by: Hans de Goede 
Tested-by: Benjamin Tissoires 
Signed-off-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

Input: alps - ignore bad data on Dell Latitudes E6440 and E7440

2014-11-14T01:42:57+00:00

Sometimes on Dell Latitude laptops psmouse/alps driver receive invalid ALPS
protocol V3 packets with bit7 set in last byte. More often it can be
reproduced on Dell Latitude E6440 or E7440 with closed lid and pushing
cover above touchpad.

If bit7 in last packet byte is set then it is not valid ALPS packet. I was
told that ALPS devices never send these packets. It is not know yet who
send those packets, it could be Dell EC, bug in BIOS and also bug in
touchpad firmware...

With this patch alps driver does not process those invalid packets, but
instead of reporting PSMOUSE_BAD_DATA, getting into out of sync state,
getting back in sync with the next byte and spam dmesg we return
PSMOUSE_FULL_PACKET. If driver is truly out of sync we'll fail the checks
on the next byte and report PSMOUSE_BAD_DATA then.

Signed-off-by: Pali Rohár 
Tested-by: Pali Rohár 
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov

Input: alps - allow up to 2 invalid packets without resetting device

2014-11-10T06:58:38+00:00

On some Dell Latitude laptops ALPS device or Dell EC send one invalid byte
in 6 bytes ALPS packet. In this case psmouse driver enter out of sync
state. It looks like that all other bytes in packets are valid and also
device working properly. So there is no need to do full device reset, just
need to wait for byte which match condition for first byte (start of
packet). Because ALPS packets are bigger (6 or 8 bytes) default limit is
small.

This patch increase number of invalid bytes to size of 2 ALPS packets which
psmouse driver can drop before do full reset.

Resetting ALPS devices take some time and when doing reset on some Dell
laptops touchpad, trackstick and also keyboard do not respond. So it is
better to do it only if really necessary.

Signed-off-by: Pali Rohár 
Tested-by: Pali Rohár 
Reviewed-by: Hans de Goede 
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov

Input: alps - ignore potential bare packets when device is out of sync

2014-11-09T07:51:30+00:00

5th and 6th byte of ALPS trackstick V3 protocol match condition for first
byte of PS/2 3 bytes packet. When driver enters out of sync state and ALPS
trackstick is sending data then driver match 5th, 6th and next 1st bytes as
PS/2.

It basically means if user is using trackstick when driver is in out of
sync state driver will never resync. Processing these bytes as 3 bytes PS/2
data cause total mess (random cursor movements, random clicks) and make
trackstick unusable until psmouse driver decide to do full device reset.

Lot of users reported problems with ALPS devices on Dell Latitude E6440,
E6540 and E7440 laptops. ALPS device or Dell EC for unknown reason send
some invalid ALPS PS/2 bytes which cause driver out of sync. It looks like
that i8042 and psmouse/alps driver always receive group of 6 bytes packets
so there are no missing bytes and no bytes were inserted between valid
ones.

This patch does not fix root of problem with ALPS devices found in Dell
Latitude laptops but it does not allow to process some (invalid)
subsequence of 6 bytes ALPS packets as 3 bytes PS/2 when driver is out of
sync.

So with this patch trackstick input device does not report bogus data when
also driver is out of sync, so trackstick should be usable on those
machines.

Signed-off-by: Pali Rohár 
Tested-by: Pali Rohár 
Cc: stable@vger.kernel.org
Reviewed-by: Hans de Goede 
Signed-off-by: Dmitry Torokhov

Input: alps - fix v4 button press recognition

2014-10-15T17:57:19+00:00

Since the change to struct input_mt_pos some variables are now bitfields
instead of integers. Automatic conversion from integer to bitfield entry
destroys information, therefore enforce boolean interpretation instead.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=1114768
Fixes: 02d04254a5df ("Input: alps - use struct input_mt_pos to track coordinates")
Signed-off-by: Andreas Bosch 
Signed-off-by: Dmitry Torokhov

Input: add missing POINTER / DIRECT properties to a bunch of drivers

2014-09-08T21:58:12+00:00

I've not done a full audit of all mouse drivers, I noticed these ones were
missing the POINTER property while working on the POINTING_STICK property.

Signed-off-by: Hans de Goede 
Signed-off-by: Dmitry Torokhov

Input: add INPUT_PROP_POINTING_STICK property

2014-09-08T21:58:11+00:00

It is useful for userspace to know that there not dealing with a regular
mouse but rather with a pointing stick (e.g. a trackpoint) so that
userspace can e.g. automatically enable middle button scrollwheel
emulation.

It is impossible to tell the difference from the evdev info without
resorting to putting a list of device / driver names in userspace, this is
undesirable.

Add a property which allows userspace to see if a device is a pointing
stick, and set it on all the pointing stick drivers.

Signed-off-by: Hans de Goede 
Acked-by: Benjamin Tissoires 
Acked-by: Peter Hutterer 
Signed-off-by: Dmitry Torokhov

Input: ALPS - suppress message about 'Unknown touchpad'

2014-08-26T22:17:30+00:00

When we fail to match data returned by E7 and EC reports we state that we
found "Unknown ALPS touchpad" whereas it is most likely it is not ALPS
touchpad at all. Change wording a bit and reduce the message to debug so
that it does not litter users logs and confuse them.

Reported-by: Paul Menzel 
Acked-by: Hans de Goede 
Signed-off-by: Dmitry Torokhov