[PATCH libinput v4 1/2] evdev: use a different filter for low resolution touchpad on the Lenovo X230
Benjamin Tissoires
benjamin.tissoires at gmail.com
Mon Apr 20 11:29:44 PDT 2015
Those touchpads presents an actual lower resolution that what is
advertised.
We see some jumps from the cursor due to the big steps in X and Y
when we are receiving data.
For instance, we receive:
E: 13.471932 0003 0000 16366 # EV_ABS / ABS_X 16366
E: 13.471932 0003 0001 9591 # EV_ABS / ABS_Y 9591
E: 13.471932 0000 0000 0000 # ------------ SYN_REPORT (0) ----------
E: 13.479924 0003 0000 16316 # EV_ABS / ABS_X 16316
E: 13.479924 0003 0001 9491 # EV_ABS / ABS_Y 9491
E: 13.479924 0000 0000 0000 # ------------ SYN_REPORT (0) ----------
E: 13.487939 0003 0000 16271 # EV_ABS / ABS_X 16271
E: 13.487939 0003 0001 9403 # EV_ABS / ABS_Y 9403
E: 13.487939 0000 0000 0000 # ------------ SYN_REPORT (0) ----------
-> jumps of ~50 in X in each report, and ~100 for Y.
Use a three segments acceleration profile to sort this out:
- slow down a lot when speed is below 0.8 + threshold
- use a somewhat half acceleration when speed is in
]0.8 + threshold .. 2.0]
- use the same acceleration than regular touchpads if the speed is
greater than 2.0
Signed-off-by: Benjamin Tissoires <benjamin.tissoires at gmail.com>
Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
Change in v4:
- dropped the generic linear pointer acceleration
- use our own 3 segments acceleration profile
doc/device-configuration-via-udev.dox | 9 +++++++
src/evdev-mt-touchpad.c | 14 +++++++++--
src/evdev.c | 23 +++++++++++++++++++
src/evdev.h | 7 +++++
src/filter.c | 40 +++++++++++++++++++++++++++++++++
src/filter.h | 5 ++++
6 files changed, 95 insertions(+), 3 deletions(-)
diff --git a/doc/device-configuration-via-udev.dox b/doc/device-configuration-via-udev.dox
index fc1c0af..c570913 100644
--- a/doc/device-configuration-via-udev.dox
+++ b/doc/device-configuration-via-udev.dox
@@ -57,6 +57,15 @@ See @ref motion_normalization for details.
<dd>The angle in degrees for each click on a mouse wheel. See
libinput_pointer_get_axis_source() for details.
</dd>
+<dt>LIBINPUT_MODEL_LENOVO_X230</dt>
+<dd><b>Do not use for anything except a Lenovo X230 series</b> (you have been
+warned).
+This flag allows libinput to apply a different acceleration profile for the
+touchpads of this series of laptops to counter a hardware deficiency. It may
+also be use to tune other parts of the inputs of these laptops, so the effects
+of this property may change anytime and will be only tested against the
+mentioned laptop series.
+</dd>
</dl>
Below is an example udev rule to assign "seat1" to a device from vendor
diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
index cccf033..d5ce880 100644
--- a/src/evdev-mt-touchpad.c
+++ b/src/evdev-mt-touchpad.c
@@ -998,6 +998,7 @@ static int
tp_init_accel(struct tp_dispatch *tp, double diagonal)
{
int res_x, res_y;
+ accel_profile_func_t profile;
res_x = tp->device->abs.absinfo_x->resolution;
res_y = tp->device->abs.absinfo_y->resolution;
@@ -1021,9 +1022,16 @@ tp_init_accel(struct tp_dispatch *tp, double diagonal)
tp->accel.y_scale_coeff = DEFAULT_ACCEL_NUMERATOR / diagonal;
}
- if (evdev_device_init_pointer_acceleration(
- tp->device,
- touchpad_accel_profile_linear) == -1)
+ switch (tp->device->model) {
+ case EVDEV_MODEL_LENOVO_X230:
+ profile = touchpad_lenovo_x230_accel_profile;
+ break;
+ default:
+ profile = touchpad_accel_profile_linear;
+ break;
+ }
+
+ if (evdev_device_init_pointer_acceleration(tp->device, profile) == -1)
return -1;
return 0;
diff --git a/src/evdev.c b/src/evdev.c
index da33eae..7743c06 100644
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -1389,6 +1389,28 @@ evdev_read_dpi_prop(struct evdev_device *device)
return dpi;
}
+static inline enum evdev_device_model
+evdev_read_model(struct evdev_device *device)
+{
+ const struct model_map {
+ const char *property;
+ enum evdev_device_model model;
+ } model_map[] = {
+ { "LIBINPUT_MODEL_LENOVO_X230", EVDEV_MODEL_LENOVO_X230 },
+ { NULL, EVDEV_MODEL_DEFAULT },
+ };
+ const struct model_map *m = model_map;
+
+ while (m->property) {
+ if (!!udev_device_get_property_value(device->udev_device,
+ m->property))
+ break;
+ m++;
+ }
+
+ return m->model;
+}
+
/* Return 1 if the given resolutions have been set, or 0 otherwise */
inline int
evdev_fix_abs_resolution(struct evdev_device *device,
@@ -1901,6 +1923,7 @@ evdev_device_create(struct libinput_seat *seat,
device->scroll.wheel_click_angle =
evdev_read_wheel_click_prop(device);
device->dpi = evdev_read_dpi_prop(device);
+ device->model = evdev_read_model(device);
/* at most 5 SYN_DROPPED log-messages per 30s */
ratelimit_init(&device->syn_drop_limit, 30ULL * 1000, 5);
diff --git a/src/evdev.h b/src/evdev.h
index 9b1dcc3..803f34d 100644
--- a/src/evdev.h
+++ b/src/evdev.h
@@ -86,6 +86,11 @@ enum evdev_middlebutton_event {
MIDDLEBUTTON_EVENT_ALL_UP,
};
+enum evdev_device_model {
+ EVDEV_MODEL_DEFAULT,
+ EVDEV_MODEL_LENOVO_X230,
+};
+
struct mt_slot {
int32_t seat_slot;
struct device_coords point;
@@ -195,6 +200,8 @@ struct evdev_device {
int dpi; /* HW resolution */
struct ratelimit syn_drop_limit; /* ratelimit for SYN_DROPPED logging */
+
+ enum evdev_device_model model;
};
#define EVDEV_UNHANDLED_DEVICE ((struct evdev_device *) 1)
diff --git a/src/filter.c b/src/filter.c
index 962d74d..5994571 100644
--- a/src/filter.c
+++ b/src/filter.c
@@ -345,3 +345,43 @@ touchpad_accel_profile_linear(struct motion_filter *filter,
return speed_out * TP_MAGIC_SLOWDOWN;
}
+
+double
+touchpad_lenovo_x230_accel_profile(struct motion_filter *filter,
+ void *data,
+ double speed_in,
+ uint64_t time)
+{
+ /* Those touchpads presents an actual lower resolution that what is
+ * advertised. We see some jumps from the cursor due to the big steps
+ * in X and Y when we are receiving data.
+ * Use a three segments acceleration profile to sort this out:
+ * - slow down a lot when speed is below 0.8 + threshold
+ * - use a somewhat half acceleration when speed is in ]0.8 + threshold .. 2.0]
+ * - use the same acceleration than regular touchpads if the speed is
+ * greater than 2.0
+ */
+ double speed_out;
+ struct pointer_accelerator *accel_filter =
+ (struct pointer_accelerator *)filter;
+
+ double s1, s2, s3;
+ const double max_accel = accel_filter->accel * 0.4; /* unitless factor, same for regular touchpads */
+ const double threshold = accel_filter->threshold;
+ const double incline = accel_filter->incline;
+
+ s1 = speed_in * 0.05;
+ s2 = 0.1 + (speed_in - threshold * 0.5) * incline * 0.10;
+ s3 = 0.37 + (speed_in - threshold * 2.0) * incline * 0.16;
+
+ if (speed_in <= 0.8 + threshold)
+ speed_out = s1;
+ else if (speed_in <= 2)
+ speed_out = s2;
+ else
+ speed_out = s3;
+
+ speed_out = min(max_accel, speed_out);
+
+ return speed_out;
+}
diff --git a/src/filter.h b/src/filter.h
index 70363a6..a053860 100644
--- a/src/filter.h
+++ b/src/filter.h
@@ -67,4 +67,9 @@ touchpad_accel_profile_linear(struct motion_filter *filter,
void *data,
double speed_in,
uint64_t time);
+double
+touchpad_lenovo_x230_accel_profile(struct motion_filter *filter,
+ void *data,
+ double speed_in,
+ uint64_t time);
#endif /* FILTER_H */
--
1.7.1
More information about the wayland-devel
mailing list