evdev: hook up a generic enable/disable interface for devices
[platform/upstream/libinput.git] / src / evdev-mt-touchpad.c
index 73ea8a8..d831b83 100644 (file)
 #include <assert.h>
 #include <math.h>
 #include <stdbool.h>
+#include <limits.h>
 
 #include "evdev-mt-touchpad.h"
 
-#define DEFAULT_CONSTANT_ACCEL_NUMERATOR 50
-#define DEFAULT_MIN_ACCEL_FACTOR 0.16
-#define DEFAULT_MAX_ACCEL_FACTOR 1.0
+#define DEFAULT_ACCEL_NUMERATOR 1200.0
 #define DEFAULT_HYSTERESIS_MARGIN_DENOMINATOR 700.0
 
 static inline int
@@ -42,30 +41,8 @@ tp_hysteresis(int in, int center, int margin)
 
        if (diff > margin)
                return center + diff - margin;
-       else if (diff < -margin)
+       else
                return center + diff + margin;
-       return center + diff;
-}
-
-static double
-tp_accel_profile(struct motion_filter *filter,
-                void *data,
-                double velocity,
-                uint32_t time)
-{
-       struct tp_dispatch *tp =
-               (struct tp_dispatch *) data;
-
-       double accel_factor;
-
-       accel_factor = velocity * tp->accel.constant_factor;
-
-       if (accel_factor > tp->accel.max_factor)
-               accel_factor = tp->accel.max_factor;
-       else if (accel_factor < tp->accel.min_factor)
-               accel_factor = tp->accel.min_factor;
-
-       return accel_factor;
 }
 
 static inline struct tp_motion *
@@ -80,14 +57,15 @@ tp_motion_history_offset(struct tp_touch *t, int offset)
 
 static void
 tp_filter_motion(struct tp_dispatch *tp,
-                double *dx, double *dy, uint32_t time)
+                double *dx, double *dy, uint64_t time)
 {
        struct motion_params motion;
 
-       motion.dx = *dx;
-       motion.dy = *dy;
+       motion.dx = *dx * tp->accel.x_scale_coeff;
+       motion.dy = *dy * tp->accel.y_scale_coeff;
 
-       filter_dispatch(tp->filter, &motion, tp, time);
+       if (motion.dx != 0.0 || motion.dy != 0.0)
+               filter_dispatch(tp->filter, &motion, tp, time);
 
        *dx = motion.dx;
        *dy = motion.dy;
@@ -139,30 +117,44 @@ tp_motion_history_reset(struct tp_touch *t)
 static inline struct tp_touch *
 tp_current_touch(struct tp_dispatch *tp)
 {
-       return &tp->touches[min(tp->slot, tp->ntouches)];
+       return &tp->touches[min(tp->slot, tp->ntouches - 1)];
+}
+
+static inline struct tp_touch *
+tp_get_touch(struct tp_dispatch *tp, unsigned int slot)
+{
+       assert(slot < tp->ntouches);
+       return &tp->touches[slot];
 }
 
 static inline void
-tp_begin_touch(struct tp_dispatch *tp, struct tp_touch *t)
+tp_begin_touch(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
 {
-       if (t->state != TOUCH_UPDATE) {
-               tp_motion_history_reset(t);
-               t->dirty = true;
-               t->state = TOUCH_BEGIN;
-               tp->nfingers_down++;
-               assert(tp->nfingers_down >= 1);
-               tp->queued |= TOUCHPAD_EVENT_MOTION;
-       }
+       if (t->state == TOUCH_BEGIN || t->state == TOUCH_UPDATE)
+               return;
+
+       tp_motion_history_reset(t);
+       t->dirty = true;
+       t->state = TOUCH_BEGIN;
+       t->pinned.is_pinned = false;
+       t->millis = time;
+       tp->nfingers_down++;
+       assert(tp->nfingers_down >= 1);
+       tp->queued |= TOUCHPAD_EVENT_MOTION;
 }
 
 static inline void
-tp_end_touch(struct tp_dispatch *tp, struct tp_touch *t)
+tp_end_touch(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
 {
-       if (t->state == TOUCH_NONE)
+       if (t->state == TOUCH_END || t->state == TOUCH_NONE)
                return;
 
        t->dirty = true;
+       t->is_pointer = false;
+       t->palm.is_palm = false;
        t->state = TOUCH_END;
+       t->pinned.is_pinned = false;
+       t->millis = time;
        assert(tp->nfingers_down >= 1);
        tp->nfingers_down--;
        tp->queued |= TOUCHPAD_EVENT_MOTION;
@@ -171,7 +163,7 @@ tp_end_touch(struct tp_dispatch *tp, struct tp_touch *t)
 static double
 tp_estimate_delta(int x0, int x1, int x2, int x3)
 {
-       return (x0 + x1 - x2 - x3) / 4;
+       return (x0 + x1 - x2 - x3) / 4.0;
 }
 
 void
@@ -196,7 +188,7 @@ tp_get_delta(struct tp_touch *t, double *dx, double *dy)
 static void
 tp_process_absolute(struct tp_dispatch *tp,
                    const struct input_event *e,
-                   uint32_t time)
+                   uint64_t time)
 {
        struct tp_touch *t = tp_current_touch(tp);
 
@@ -217,53 +209,241 @@ tp_process_absolute(struct tp_dispatch *tp,
                tp->slot = e->value;
                break;
        case ABS_MT_TRACKING_ID:
-               t->millis = time;
                if (e->value != -1)
-                       tp_begin_touch(tp, t);
+                       tp_begin_touch(tp, t, time);
                else
-                       tp_end_touch(tp, t);
+                       tp_end_touch(tp, t, time);
        }
 }
 
 static void
+tp_process_absolute_st(struct tp_dispatch *tp,
+                      const struct input_event *e,
+                      uint64_t time)
+{
+       struct tp_touch *t = tp_current_touch(tp);
+
+       switch(e->code) {
+       case ABS_X:
+               t->x = e->value;
+               t->millis = time;
+               t->dirty = true;
+               tp->queued |= TOUCHPAD_EVENT_MOTION;
+               break;
+       case ABS_Y:
+               t->y = e->value;
+               t->millis = time;
+               t->dirty = true;
+               tp->queued |= TOUCHPAD_EVENT_MOTION;
+               break;
+       }
+}
+
+static void
+tp_process_fake_touch(struct tp_dispatch *tp,
+                     const struct input_event *e,
+                     uint64_t time)
+{
+       struct tp_touch *t;
+       unsigned int fake_touches;
+       unsigned int nfake_touches;
+       unsigned int i, start;
+       unsigned int shift;
+
+       if (e->code != BTN_TOUCH &&
+           (e->code < BTN_TOOL_DOUBLETAP || e->code > BTN_TOOL_QUADTAP))
+               return;
+
+       shift = e->code == BTN_TOUCH ? 0 : (e->code - BTN_TOOL_DOUBLETAP + 1);
+
+       if (e->value)
+               tp->fake_touches |= 1 << shift;
+       else
+               tp->fake_touches &= ~(0x1 << shift);
+
+       fake_touches = tp->fake_touches;
+       nfake_touches = 0;
+       while (fake_touches) {
+               nfake_touches++;
+               fake_touches >>= 1;
+       }
+
+       /* For single touch tps we use BTN_TOUCH for begin / end of touch 0 */
+       start = tp->has_mt ? tp->real_touches : 0;
+       for (i = start; i < tp->ntouches; i++) {
+               t = tp_get_touch(tp, i);
+               if (i < nfake_touches)
+                       tp_begin_touch(tp, t, time);
+               else
+                       tp_end_touch(tp, t, time);
+       }
+
+       /* On mt the actual touch info may arrive after BTN_TOOL_FOO */
+       assert(tp->has_mt || tp->nfingers_down == nfake_touches);
+}
+
+static void
 tp_process_key(struct tp_dispatch *tp,
               const struct input_event *e,
-              uint32_t time)
+              uint64_t time)
 {
-       uint32_t mask;
-
        switch (e->code) {
                case BTN_LEFT:
                case BTN_MIDDLE:
                case BTN_RIGHT:
-                       mask = 1 << (e->code - BTN_LEFT);
-                       if (e->value) {
-                               tp->buttons.state |= mask;
-                               tp->queued |= TOUCHPAD_EVENT_BUTTON_PRESS;
-                       } else {
-                               tp->buttons.state &= ~mask;
-                               tp->queued |= TOUCHPAD_EVENT_BUTTON_RELEASE;
-                       }
+                       tp_process_button(tp, e, time);
+                       break;
+               case BTN_TOUCH:
+               case BTN_TOOL_DOUBLETAP:
+               case BTN_TOOL_TRIPLETAP:
+               case BTN_TOOL_QUADTAP:
+                       tp_process_fake_touch(tp, e, time);
                        break;
        }
 }
 
 static void
-tp_process_state(struct tp_dispatch *tp, uint32_t time)
+tp_unpin_finger(struct tp_dispatch *tp, struct tp_touch *t)
+{
+       unsigned int xdist, ydist;
+
+       if (!t->pinned.is_pinned)
+               return;
+
+       xdist = abs(t->x - t->pinned.center_x);
+       ydist = abs(t->y - t->pinned.center_y);
+
+       if (xdist * xdist + ydist * ydist >=
+                       tp->buttons.motion_dist * tp->buttons.motion_dist) {
+               t->pinned.is_pinned = false;
+               tp_set_pointer(tp, t);
+       }
+}
+
+static void
+tp_pin_fingers(struct tp_dispatch *tp)
 {
        struct tp_touch *t;
 
        tp_for_each_touch(tp, t) {
+               t->is_pointer = false;
+               t->pinned.is_pinned = true;
+               t->pinned.center_x = t->x;
+               t->pinned.center_y = t->y;
+       }
+}
+
+static int
+tp_touch_active(struct tp_dispatch *tp, struct tp_touch *t)
+{
+       return (t->state == TOUCH_BEGIN || t->state == TOUCH_UPDATE) &&
+               !t->palm.is_palm &&
+               !t->pinned.is_pinned && tp_button_touch_active(tp, t);
+}
+
+void
+tp_set_pointer(struct tp_dispatch *tp, struct tp_touch *t)
+{
+       struct tp_touch *tmp = NULL;
+
+       /* Only set the touch as pointer if we don't have one yet */
+       tp_for_each_touch(tp, tmp) {
+               if (tmp->is_pointer)
+                       return;
+       }
+
+       if (tp_touch_active(tp, t))
+               t->is_pointer = true;
+}
+
+static void
+tp_palm_detect(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
+{
+       const int PALM_TIMEOUT = 200; /* ms */
+       const int DIRECTIONS = NE|E|SE|SW|W|NW;
+
+       /* If labelled a touch as palm, we unlabel as palm when
+          we move out of the palm edge zone within the timeout, provided
+          the direction is within 45 degrees of the horizontal.
+        */
+       if (t->palm.is_palm) {
+               if (time < t->palm.time + PALM_TIMEOUT &&
+                   (t->x > tp->palm.left_edge && t->x < tp->palm.right_edge)) {
+                       int dirs = vector_get_direction(t->x - t->palm.x, t->y - t->palm.y);
+                       if ((dirs & DIRECTIONS) && !(dirs & ~DIRECTIONS)) {
+                               t->palm.is_palm = false;
+                               tp_set_pointer(tp, t);
+                       }
+               }
+               return;
+       }
+
+       /* palm must start in exclusion zone, it's ok to move into
+          the zone without being a palm */
+       if (t->state != TOUCH_BEGIN ||
+           (t->x > tp->palm.left_edge && t->x < tp->palm.right_edge))
+               return;
+
+       /* don't detect palm in software button areas, it's
+          likely that legitimate touches start in the area
+          covered by the exclusion zone */
+       if (tp->buttons.is_clickpad &&
+           tp_button_is_inside_softbutton_area(tp, t))
+               return;
+
+       t->palm.is_palm = true;
+       t->palm.time = time;
+       t->palm.x = t->x;
+       t->palm.y = t->y;
+}
+
+static void
+tp_process_state(struct tp_dispatch *tp, uint64_t time)
+{
+       struct tp_touch *t;
+       struct tp_touch *first = tp_get_touch(tp, 0);
+       unsigned int i;
+
+       for (i = 0; i < tp->ntouches; i++) {
+               t = tp_get_touch(tp, i);
+
+               /* semi-mt finger postions may "jump" when nfingers changes */
+               if (tp->semi_mt && tp->nfingers_down != tp->old_nfingers_down)
+                       tp_motion_history_reset(t);
+
+               if (i >= tp->real_touches && t->state != TOUCH_NONE) {
+                       t->x = first->x;
+                       t->y = first->y;
+                       if (!t->dirty)
+                               t->dirty = first->dirty;
+               }
+
                if (!t->dirty)
                        continue;
 
+               tp_palm_detect(tp, t, time);
+
                tp_motion_hysteresis(tp, t);
                tp_motion_history_push(t);
+
+               tp_unpin_finger(tp, t);
        }
+
+       tp_button_handle_state(tp, time);
+
+       /*
+        * We have a physical button down event on a clickpad. To avoid
+        * spurious pointer moves by the clicking finger we pin all fingers.
+        * We unpin fingers when they move more then a certain threshold to
+        * to allow drag and drop.
+        */
+       if ((tp->queued & TOUCHPAD_EVENT_BUTTON_PRESS) &&
+           tp->buttons.is_clickpad)
+               tp_pin_fingers(tp);
 }
 
 static void
-tp_post_process_state(struct tp_dispatch *tp, uint32_t time)
+tp_post_process_state(struct tp_dispatch *tp, uint64_t time)
 {
        struct tp_touch *t;
 
@@ -279,13 +459,14 @@ tp_post_process_state(struct tp_dispatch *tp, uint32_t time)
                t->dirty = false;
        }
 
+       tp->old_nfingers_down = tp->nfingers_down;
        tp->buttons.old_state = tp->buttons.state;
 
        tp->queued = TOUCHPAD_EVENT_NONE;
 }
 
 static void
-tp_post_twofinger_scroll(struct tp_dispatch *tp, uint32_t time)
+tp_post_twofinger_scroll(struct tp_dispatch *tp, uint64_t time)
 {
        struct tp_touch *t;
        int nchanged = 0;
@@ -293,13 +474,15 @@ tp_post_twofinger_scroll(struct tp_dispatch *tp, uint32_t time)
        double tmpx, tmpy;
 
        tp_for_each_touch(tp, t) {
-               if (t->dirty) {
+               if (tp_touch_active(tp, t) && t->dirty) {
                        nchanged++;
                        tp_get_delta(t, &tmpx, &tmpy);
 
                        dx += tmpx;
                        dy += tmpy;
                }
+               /* Stop spurious MOTION events at the end of scrolling */
+               t->is_pointer = false;
        }
 
        if (nchanged == 0)
@@ -310,94 +493,121 @@ tp_post_twofinger_scroll(struct tp_dispatch *tp, uint32_t time)
 
        tp_filter_motion(tp, &dx, &dy, time);
 
-       if (dx != 0.0)
+       /* Require at least five px scrolling to start */
+       if (dy <= -5.0 || dy >= 5.0)
+               tp->scroll.direction |= (1 << LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL);
+
+       if (dx <= -5.0 || dx >= 5.0)
+               tp->scroll.direction |= (1 << LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL);
+
+       if (dy != 0.0 &&
+           (tp->scroll.direction & (1 << LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL))) {
                pointer_notify_axis(&tp->device->base,
                                    time,
-                                   LIBINPUT_POINTER_AXIS_HORIZONTAL_SCROLL,
-                                   li_fixed_from_double(dx));
-       if (dy != 0.0)
+                                   LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL,
+                                   dy);
+       }
+
+       if (dx != 0.0 &&
+           (tp->scroll.direction & (1 << LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL))) {
                pointer_notify_axis(&tp->device->base,
                                    time,
-                                   LIBINPUT_POINTER_AXIS_VERTICAL_SCROLL,
-                                   li_fixed_from_double(dy));
+                                   LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL,
+                                   dx);
+       }
 }
 
 static void
-tp_post_button_events(struct tp_dispatch *tp, uint32_t time)
+tp_stop_scroll_events(struct tp_dispatch *tp, uint64_t time)
 {
-       uint32_t current, old, button;
-
-       if ((tp->queued &
-               (TOUCHPAD_EVENT_BUTTON_PRESS|TOUCHPAD_EVENT_BUTTON_RELEASE)) == 0)
-                               return;
-
-       current = tp->buttons.state;
-       old = tp->buttons.old_state;
-       button = BTN_LEFT;
+       /* terminate scrolling with a zero scroll event */
+       if (tp->scroll.direction & (1 << LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL))
+               pointer_notify_axis(&tp->device->base,
+                                   time,
+                                   LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL,
+                                   0);
+       if (tp->scroll.direction & (1 << LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL))
+               pointer_notify_axis(&tp->device->base,
+                                   time,
+                                   LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL,
+                                   0);
 
-       while (current || old) {
-               enum libinput_pointer_button_state state;
+       tp->scroll.direction = 0;
+}
 
-               if ((current & 0x1) ^ (old & 0x1)) {
-                       if (!!(current & 0x1))
-                               state = LIBINPUT_POINTER_BUTTON_STATE_PRESSED;
-                       else
-                               state = LIBINPUT_POINTER_BUTTON_STATE_RELEASED;
+static int
+tp_post_scroll_events(struct tp_dispatch *tp, uint64_t time)
+{
+       struct tp_touch *t;
+       int nfingers_down = 0;
 
-                       pointer_notify_button(&tp->device->base,
-                                             time,
-                                             button,
-                                             state);
-               }
+       /* Only count active touches for 2 finger scrolling */
+       tp_for_each_touch(tp, t) {
+               if (tp_touch_active(tp, t))
+                       nfingers_down++;
+       }
 
-               button++;
-               current >>= 1;
-               old >>= 1;
+       if (nfingers_down != 2) {
+               tp_stop_scroll_events(tp, time);
+               return 0;
        }
+
+       tp_post_twofinger_scroll(tp, time);
+       return 1;
 }
 
 static void
-tp_post_events(struct tp_dispatch *tp, uint32_t time)
+tp_post_events(struct tp_dispatch *tp, uint64_t time)
 {
        struct tp_touch *t = tp_current_touch(tp);
        double dx, dy;
+       int consumed = 0;
 
-       if (tp->nfingers_down > 2) {
-               return;
-       } else if (tp->nfingers_down == 2) {
-               tp_post_twofinger_scroll(tp, time);
+       consumed |= tp_tap_handle_state(tp, time);
+       consumed |= tp_post_button_events(tp, time);
+
+       if (consumed) {
+               tp_stop_scroll_events(tp, time);
                return;
        }
 
+       if (tp_post_scroll_events(tp, time) != 0)
+               return;
 
-       if (t->history.count < 4)
+       if (!t->is_pointer) {
+               tp_for_each_touch(tp, t) {
+                       if (t->is_pointer)
+                               break;
+               }
+       }
+
+       if (!t->is_pointer ||
+           !t->dirty ||
+           t->history.count < TOUCHPAD_MIN_SAMPLES)
                return;
 
        tp_get_delta(t, &dx, &dy);
        tp_filter_motion(tp, &dx, &dy, time);
 
-       if (dx != 0 || dy != 0)
-               pointer_notify_motion(
-                       &tp->device->base,
-                       time,
-                       li_fixed_from_double(dx),
-                       li_fixed_from_double(dy));
-
-       tp_post_button_events(tp, time);
+       if (dx != 0.0 || dy != 0.0)
+               pointer_notify_motion(&tp->device->base, time, dx, dy);
 }
 
 static void
 tp_process(struct evdev_dispatch *dispatch,
           struct evdev_device *device,
           struct input_event *e,
-          uint32_t time)
+          uint64_t time)
 {
        struct tp_dispatch *tp =
                (struct tp_dispatch *)dispatch;
 
        switch (e->type) {
        case EV_ABS:
-               tp_process_absolute(tp, e, time);
+               if (tp->has_mt)
+                       tp_process_absolute(tp, e, time);
+               else
+                       tp_process_absolute_st(tp, e, time);
                break;
        case EV_KEY:
                tp_process_key(tp, e, time);
@@ -416,8 +626,10 @@ tp_destroy(struct evdev_dispatch *dispatch)
        struct tp_dispatch *tp =
                (struct tp_dispatch*)dispatch;
 
-       if (tp->filter)
-               tp->filter->interface->destroy(tp->filter);
+       tp_destroy_tap(tp);
+       tp_destroy_buttons(tp);
+
+       filter_destroy(tp->filter);
        free(tp->touches);
        free(tp);
 }
@@ -427,37 +639,148 @@ static struct evdev_dispatch_interface tp_interface = {
        tp_destroy
 };
 
+static void
+tp_init_touch(struct tp_dispatch *tp,
+             struct tp_touch *t)
+{
+       t->tp = tp;
+}
+
 static int
 tp_init_slots(struct tp_dispatch *tp,
              struct evdev_device *device)
 {
-       struct input_absinfo absinfo = {0};
+       const struct input_absinfo *absinfo;
+       struct map {
+               unsigned int code;
+               int ntouches;
+       } max_touches[] = {
+               { BTN_TOOL_QUINTTAP, 5 },
+               { BTN_TOOL_QUADTAP, 4 },
+               { BTN_TOOL_TRIPLETAP, 3 },
+               { BTN_TOOL_DOUBLETAP, 2 },
+       };
+       struct map *m;
+       unsigned int i, n_btn_tool_touches = 1;
+
+       absinfo = libevdev_get_abs_info(device->evdev, ABS_MT_SLOT);
+       if (absinfo) {
+               tp->real_touches = absinfo->maximum + 1;
+               tp->slot = absinfo->value;
+               tp->has_mt = true;
+       } else {
+               tp->real_touches = 1;
+               tp->slot = 0;
+               tp->has_mt = false;
+       }
+
+       tp->semi_mt = libevdev_has_property(device->evdev, INPUT_PROP_SEMI_MT);
+
+       ARRAY_FOR_EACH(max_touches, m) {
+               if (libevdev_has_event_code(device->evdev,
+                                           EV_KEY,
+                                           m->code)) {
+                       n_btn_tool_touches = m->ntouches;
+                       break;
+               }
+       }
 
-       ioctl(device->fd, EVIOCGABS(ABS_MT_SLOT), &absinfo);
+       tp->ntouches = max(tp->real_touches, n_btn_tool_touches);
+       tp->touches = calloc(tp->ntouches, sizeof(struct tp_touch));
+       if (!tp->touches)
+               return -1;
 
-       tp->ntouches = absinfo.maximum + 1;
-       tp->touches = calloc(tp->ntouches,
-                            sizeof(struct tp_touch));
-       tp->slot = absinfo.value;
+       for (i = 0; i < tp->ntouches; i++)
+               tp_init_touch(tp, &tp->touches[i]);
 
        return 0;
 }
 
 static int
-tp_init_accel(struct tp_dispatch *touchpad, double diagonal)
+tp_init_accel(struct tp_dispatch *tp, double diagonal)
 {
        struct motion_filter *accel;
+       int res_x, res_y;
+
+       if (tp->has_mt) {
+               res_x = libevdev_get_abs_resolution(tp->device->evdev,
+                                                   ABS_MT_POSITION_X);
+               res_y = libevdev_get_abs_resolution(tp->device->evdev,
+                                                   ABS_MT_POSITION_Y);
+       } else {
+               res_x = libevdev_get_abs_resolution(tp->device->evdev,
+                                                   ABS_X);
+               res_y = libevdev_get_abs_resolution(tp->device->evdev,
+                                                   ABS_Y);
+       }
 
-       touchpad->accel.constant_factor =
-               DEFAULT_CONSTANT_ACCEL_NUMERATOR / diagonal;
-       touchpad->accel.min_factor = DEFAULT_MIN_ACCEL_FACTOR;
-       touchpad->accel.max_factor = DEFAULT_MAX_ACCEL_FACTOR;
+       /*
+        * Not all touchpads report the same amount of units/mm (resolution).
+        * Normalize motion events to a resolution of 15.74 units/mm
+        * (== 400 dpi) as base (unaccelerated) speed. This also evens out any
+        * differences in x and y resolution, so that a circle on the
+        * touchpad does not turn into an elipse on the screen.
+        *
+        * We pick 400dpi as thats one of the many default resolutions
+        * for USB mice, so we end up with a similar base speed on the device.
+        */
+       if (res_x > 1 && res_y > 1) {
+               tp->accel.x_scale_coeff = (400/25.4) / res_x;
+               tp->accel.y_scale_coeff = (400/25.4) / res_y;
+       } else {
+       /*
+        * For touchpads where the driver does not provide resolution, fall
+        * back to scaling motion events based on the diagonal size in units.
+        */
+               tp->accel.x_scale_coeff = DEFAULT_ACCEL_NUMERATOR / diagonal;
+               tp->accel.y_scale_coeff = DEFAULT_ACCEL_NUMERATOR / diagonal;
+       }
 
-       accel = create_pointer_accelator_filter(tp_accel_profile);
+       accel = create_pointer_accelator_filter(
+                       pointer_accel_profile_smooth_simple);
        if (accel == NULL)
                return -1;
 
-       touchpad->filter = accel;
+       tp->filter = accel;
+
+       return 0;
+}
+
+static int
+tp_init_scroll(struct tp_dispatch *tp)
+{
+       tp->scroll.direction = 0;
+
+       return 0;
+}
+
+static int
+tp_init_palmdetect(struct tp_dispatch *tp,
+                  struct evdev_device *device)
+{
+       int width;
+
+       tp->palm.right_edge = INT_MAX;
+       tp->palm.left_edge = INT_MIN;
+
+       width = abs(device->abs.absinfo_x->maximum -
+                   device->abs.absinfo_x->minimum);
+
+       /* Apple touchpads are always big enough to warrant palm detection */
+       if (evdev_device_get_id_vendor(device) != VENDOR_ID_APPLE) {
+               /* We don't know how big the touchpad is */
+               if (device->abs.absinfo_x->resolution == 1)
+                       return 0;
+
+               /* Enable palm detection on touchpads >= 80 mm. Anything smaller
+                  probably won't need it, until we find out it does */
+               if (width/device->abs.absinfo_x->resolution < 80)
+                       return 0;
+       }
+
+       /* palm edges are 5% of the width on each side */
+       tp->palm.right_edge = device->abs.absinfo_x->maximum - width * 0.05;
+       tp->palm.left_edge = device->abs.absinfo_x->minimum + width * 0.05;
 
        return 0;
 }
@@ -475,8 +798,10 @@ tp_init(struct tp_dispatch *tp,
        if (tp_init_slots(tp, device) != 0)
                return -1;
 
-       width = abs(device->abs.max_x - device->abs.min_x);
-       height = abs(device->abs.max_y - device->abs.min_y);
+       width = abs(device->abs.absinfo_x->maximum -
+                   device->abs.absinfo_x->minimum);
+       height = abs(device->abs.absinfo_y->maximum -
+                    device->abs.absinfo_y->minimum);
        diagonal = sqrt(width*width + height*height);
 
        tp->hysteresis.margin_x =
@@ -484,9 +809,23 @@ tp_init(struct tp_dispatch *tp,
        tp->hysteresis.margin_y =
                diagonal / DEFAULT_HYSTERESIS_MARGIN_DENOMINATOR;
 
+       if (tp_init_scroll(tp) != 0)
+               return -1;
+
        if (tp_init_accel(tp, diagonal) != 0)
                return -1;
 
+       if (tp_init_tap(tp) != 0)
+               return -1;
+
+       if (tp_init_buttons(tp, device) != 0)
+               return -1;
+
+       if (tp_init_palmdetect(tp, device) != 0)
+               return -1;
+
+       device->seat_caps |= EVDEV_DEVICE_POINTER;
+
        return 0;
 }