linux-toradex.git/drivers/input/mouse/synaptics.h, branch v3.10.78

Input: synaptics - add support for ForcePads

2014-10-05T21:54:12+00:00

commit 5715fc764f7753d464dbe094b5ef9cffa6e479a4 upstream.

ForcePads are found on HP EliteBook 1040 laptops. They lack any kind of
physical buttons, instead they generate primary button click when user
presses somewhat hard on the surface of the touchpad. Unfortunately they
also report primary button click whenever there are 2 or more contacts
on the pad, messing up all multi-finger gestures (2-finger scrolling,
multi-finger tapping, etc). To cope with this behavior we introduce a
delay (currently 50 msecs) in reporting primary press in case more
contacts appear.

Reviewed-by: Hans de Goede 
Signed-off-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

Input: synaptics - print firmware ID and board number at init

2012-07-08T01:20:08+00:00

Read the Firmware ID and Board Number from a synaptics device at init
and display them in the system log.

Device behavior is very board and firmware dependent.
It may prove useful for users to include this information when providing
bug reports or other feedback.

Signed-off-by: Daniel Kurtz 
Acked-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: synaptics - add support for Relative mode

2011-11-10T05:23:31+00:00

Currently, the synaptics driver puts the device into Absolute mode.
As explained in the synaptics documentation section 3.2, in this mode,
the device sends a continuous stream of packets at the maximum rate
to the host when the user's fingers are near or on the pad or
pressing buttons, and continues streaming for 1 second afterwards.
These packets are even sent when there is no new information to report,
even when they are duplicates of the previous packet.

For embedded systems this is a bit much - it results in a huge
and uninterrupted stream of interrupts at high rate.

This patch adds support for Relative mode, which can be selected as
a new psmouse protocol. In this mode, the device does not send duplicate
packets and acts like a standard PS/2 mouse. However, synaptics-specific
functionality is still available, such as the ability to set the packet
rate, and rather than disabling gestures and taps at the hardware level
unconditionally, a 'synaptics_disable_gesture' sysfs attribute has
been added to allow control of this functionality.

This solves a long standing OLPC issue: synaptics hardware enables
tap to click by default (even in the default relative mode), but we
have found this to be inappropriate for young children and first
time computer users. Enabling the synaptics driver disables tap-to-click,
but we have previously been unable to use this because it also enables
Absolute mode, which is too "spammy" for our desires and actually
overloads our EC with its continuous stream of packets. Now we can enable
the synaptics driver, disabling tap to click while retaining the less
noisy Relative mode.

Signed-off-by: Daniel Drake 
Signed-off-by: Dmitry Torokhov

Input: synaptics - process finger (<=3) transitions

2011-08-24T06:08:24+00:00

Synaptics image sensor touchpads track 5 fingers, but only report 2.
This patch attempts to deal with some idiosyncrasies of these touchpads:

 * When there are 3 or more fingers, only two are reported.
 * The touchpad tracks the 5 fingers in slot[0] through slot[4].
 * It always reports the lowest and highest valid slots in SGM and AGM
   packets, respectively.
 * The number of fingers is only reported in the SGM packet.  However,
   the number of fingers can change either before or after an AGM
   packet.
 * Thus, if an SGM reports a different number of fingers than the last
   SGM, it is impossible to tell whether the intervening AGM corresponds
   to the old number of fingers or the new number of fingers.
 * For example, when going from 2->3 fingers, it is not possible to tell
   whether tell AGM contains slot[1] (old 2nd finger) or slot[2] (new
   3rd finger).
 * When fingers are added one at at time, from 1->2->3, it is possible to
   track which slots are contained in the SGM and AGM packets:
     1 finger:  SGM = slot[0], no AGM
     2 fingers: SGM = slot[0], AGM = slot[1]
     3 fingers: SGM = slot[0], AGM = slot[2]
 * It is also possible to track which slot is contained in the SGM when 1
   of 2 fingers is removed.  This is because the touchpad sends a special
   (0,0,0) AGM packet whenever all fingers are removed except slot[0]:
     Last AGM == (0,0,0): SGM contains slot[1]
     Else: SGM contains slot[0]
 * However, once there are 3 fingers, if exactly 1 finger is removed, it
   is impossible to tell which 2 slots are contained in SGM and AGM.
   The (SGM,AGM) could be (0,1), (0,2), or (1,2). There is no way to know.
 * Similarly, if two fingers are simultaneously removed (3->1), then it
   is only possible to know if SGM still contains slot[0].
 * Since it is not possible to reliably track which slot is being
   reported, we invalidate the tracking_id every time the number of
   fingers changes until this ambiguity is resolved when:
     a) All fingers are removed.
     b) 4 or 5 fingers are touched, generates an AGM-CONTACT packet.
     c) All fingers are removed except slot[0].  In this special case, the
        ambiguity is resolved since by the (0,0,0) AGM packet.

Behavior of the driver:

When 2 or more fingers are present on the touchpad, the kernel reports
up to two MT-B slots containing the position data for two of the fingers
reported by the touchpad.  If the identity of a finger cannot be tracked
when the number-of-fingers changes, the corresponding MT-B slot will be
invalidated (track_id set to -1), and a new track_id will be assigned in
a subsequent input event report.

The driver always reports the total number of fingers using one of the
EV_KEY/BTN_TOOL_*TAP events. This could differ from the number of valid
MT-B slots for two reasons:
 a) There are more than 2 fingers on the pad.
 b) During ambiguous number-of-fingers transitions, the correct track_id
    for one or both of the slots cannot be determined, so the slots are
    invalidated.

Thus, this is a hybrid singletouch/MT-B scheme. Userspace can detect
this behavior by noting that the driver supports more EV_KEY/BTN_TOOL_*TAP
events than its maximum EV_ABS/ABS_MT_SLOT.

Signed-off-by: Daniel Kurtz 
Acked-by: Chase Douglas 
Acked-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: synaptics - decode AGM packet types

2011-08-24T06:08:16+00:00

A Synaptics image sensor tracks 5 fingers, but can only report 2.

The algorithm for choosing which 2 fingers to report and in which packet:
  Touchpad maintains 5 slots, numbered 0 to 4
  Initially all slots are empty
  As new fingers are detected, assign them to the lowest available slots
  The touchpad always reports:
    SGM: lowest numbered non-empty slot
    AGM: highest numbered non-empty slot, if there is one

In addition, these touchpads have a special AGM packet type which reports
the number of fingers currently being tracked, and which finger is in
each of the two slots.  Unfortunately, these "TYPE=2" packets are only used
when more than 3 fingers are being tracked.  When less than 4 fingers
are present, the 'w' value must be used to track how many fingers are
present, and knowing which fingers are being reported is much more
difficult, if not impossible.

Signed-off-by: Daniel Kurtz 
Acked-by: Chase Douglas 
Acked-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: synaptics - add image sensor support

2011-08-24T06:08:12+00:00

Synaptics makes (at least) two kinds of touchpad sensors:
 * Older pads use a profile sensor that could only infer the location
   of individual fingers based on the projection of their profiles
   onto row and column sensors.
 * Newer pads use an image sensor that can track true finger position
   using a two-dimensional sensor grid.

Both sensor types support an "Advanced Gesture Mode":
 When multiple fingers are detected, the touchpad sends alternating
 "Advanced Gesture Mode" (AGM) and "Simple Gesture Mode" (SGM)
 packets.
 The AGM packets have w=2, and contain reduced resolution finger data
 The SGM packets have w={0,1} and contain full resolution finger data

Profile sensors try to report the "upper" (larger y value) finger in
the SGM packet, and the lower (smaller y value) in the AGM packet.
However, due to the nature of the profile sensor, they easily get
confused when fingers cross, and can start reporting the x-coordinate
of one with the y-coordinate of the other.  Thus, for profile
sensors, "semi-mt" was created, which reports a "bounding box"
created by pairing min and max coordinates of the two pairs of
reported fingers.

Image sensors can report the actual coordinates of two of the fingers
present.  This patch detects if the touchpad is an image sensor and
reports finger data using the MT-B protocol.

NOTE: This patch only adds partial support for 2-finger gestures.
      The proper interpretation of the slot contents when more than
      two fingers are present is left to later patches.  Also,
      handling of 'number of fingers' transitions is incomplete.

Signed-off-by: Daniel Kurtz 
Acked-by: Chase Douglas 
Acked-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: synaptics - refactor agm packet parsing

2011-08-24T06:08:01+00:00

When a Synaptics touchpad is in "AGM" mode, and multiple fingers are
detected, the touchpad sends alternating "Advanced Gesture Mode" (AGM) and
"Simple Gesture Mode" (SGM) packets.
  The AGM packets have w=2, and contain reduced resolution finger data.
  The SGM packets have w={0,1} and contain full resolution finger data.

Refactor the parsing of agm packets to its own function, and rename the
synaptics_data.mt field to .agm to indicate that it contains the contents of
the last agm packet.

Signed-off-by: Daniel Kurtz 
Acked-by: Chase Douglas 
Acked-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: synaptics - fix reporting of min coordinates

2011-07-25T08:38:21+00:00

We were testing wrong bit in the extended capability query.

Reported-by: Daniel Kurtz 
Signed-off-by: Dmitry Torokhov

Input: synaptics - set minimum coordinates as reported by firmware

2011-07-09T19:33:35+00:00

Newer Synaptics firmware allows to query minimum coordinates reported by
the device, let's use this data.

Acked-by: Chase Douglas 
Acked-by: Henrik Rydberg 
Signed-off-by: Dmitry Torokhov

Input: synaptics - fuzz position for touchpad with reduced filtering

2011-07-07T06:01:09+00:00

Synaptics touchpads indicate via a capability bit when they perform reduced
filtering on position data. In such a case, use a non-zero fuzz value.
Fuzz = 8 was chosen empirically by observing the raw position data
reported by a clickpad indicating it had reduced filtering.

Signed-off-by: Daniel Kurtz 
Acked-by: Chase Douglas 
Signed-off-by: Dmitry Torokhov