Re: synaptics mouse jitter in 2.6.0
From: Dmitry Torokhov
Date: Tue Dec 23 2003 - 02:43:41 EST
On Monday 22 December 2003 10:38 pm, Dmitry Torokhov wrote:
> On Monday 22 December 2003 09:40 pm, Thomas Molina wrote:
> > I am running Fedora Core 1 updated on a Presario 12XL325 laptop. For
> > a long time during the 2.5 series I couldn't use the synaptics
> > support. As a result, I haven't tested this for some time. I just
> > compiled a fresh 2.6.0 tree, included synaptics support and now I am
> > getting mouse jitter.
> >
<..SKIP..>
>
> Right, I think I see it. The mousedev module does not do any smoothing
> of the reported coordinates which would cause the jitter you are
> seeing. Normally drivers do 3- or 4-point average.
>
> I'll cook up something to fix it. Meanwhile could you give a try Peter
> Osterlund XFree86 Synaptics driver:
> http://w1.894.telia.com/~u89404340/touchpad/index.html
>
OK, here it is. It will apply against 2.6.0 although will complain about
some offsets as I have extra stuff in my tree...
Dmitry
===================================================================
ChangeSet@xxxxxx, 2003-12-23 02:24:12-05:00, dtor_core@xxxxxxxxxxxxx
Input: when calculating deltas for touchpads that generate
absolute events use average over the last 3 packets
to remove jitter
mouse/synaptics.c | 11 ++++---
mousedev.c | 84 +++++++++++++++++++++++++++++++-----------------------
2 files changed, 56 insertions(+), 39 deletions(-)
===================================================================
diff -Nru a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
--- a/drivers/input/mouse/synaptics.c Tue Dec 23 02:25:14 2003
+++ b/drivers/input/mouse/synaptics.c Tue Dec 23 02:25:14 2003
@@ -553,15 +553,18 @@
finger_width = 0;
}
- /* Post events */
+ /* Post events
+ * BTN_TOUCH has to be first as mousedev relies on it when doing
+ * absolute -> relative conversion
+ */
+ if (hw.z > 30) input_report_key(dev, BTN_TOUCH, 1);
+ if (hw.z < 25) input_report_key(dev, BTN_TOUCH, 0);
+
if (hw.z > 0) {
input_report_abs(dev, ABS_X, hw.x);
input_report_abs(dev, ABS_Y, YMAX_NOMINAL + YMIN_NOMINAL - hw.y);
}
input_report_abs(dev, ABS_PRESSURE, hw.z);
-
- if (hw.z > 30) input_report_key(dev, BTN_TOUCH, 1);
- if (hw.z < 25) input_report_key(dev, BTN_TOUCH, 0);
input_report_abs(dev, ABS_TOOL_WIDTH, finger_width);
input_report_key(dev, BTN_TOOL_FINGER, num_fingers == 1);
diff -Nru a/drivers/input/mousedev.c b/drivers/input/mousedev.c
--- a/drivers/input/mousedev.c Tue Dec 23 02:25:14 2003
+++ b/drivers/input/mousedev.c Tue Dec 23 02:25:14 2003
@@ -53,12 +53,14 @@
struct fasync_struct *fasync;
struct mousedev *mousedev;
struct list_head node;
- int dx, dy, dz, oldx, oldy;
- signed char ps2[6];
+ int dx, dy, dz;
+ int old_x[4], old_y[4];
unsigned long buttons;
+ signed char ps2[6];
unsigned char ready, buffer, bufsiz;
unsigned char mode, imexseq, impsseq;
- int finger;
+ unsigned int pkt_count;
+ unsigned char touch;
};
#define MOUSEDEV_SEQ_LEN 6
@@ -74,49 +76,49 @@
static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
+#define fx(i) (list->old_x[(list->pkt_count - (i)) & 03])
+#define fy(i) (list->old_y[(list->pkt_count - (i)) & 03])
+
static void mousedev_abs_event(struct input_handle *handle, struct mousedev_list *list, unsigned int code, int value)
{
int size;
+ int touchpad;
/* Ignore joysticks */
if (test_bit(BTN_TRIGGER, handle->dev->keybit))
return;
- /* Handle touchpad data */
- if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit)) {
+ touchpad = test_bit(BTN_TOOL_FINGER, handle->dev->keybit);
- if (list->finger && list->finger < 3)
- list->finger++;
-
- switch (code) {
- case ABS_X:
- if (list->finger == 3)
- list->dx += (value - list->oldx) / 8;
- list->oldx = value;
- return;
- case ABS_Y:
- if (list->finger == 3)
- list->dy -= (value - list->oldy) / 8;
- list->oldy = value;
- return;
- }
- return;
- }
-
- /* Handle tablet data */
switch (code) {
case ABS_X:
- size = handle->dev->absmax[ABS_X] - handle->dev->absmin[ABS_X];
- if (size == 0) size = xres;
- list->dx += (value * xres - list->oldx) / size;
- list->oldx += list->dx * size;
- return;
+ if (touchpad) {
+ if (list->touch) {
+ fx(0) = value;
+ if (list->pkt_count >= 2)
+ list->dx = ((fx(0) - fx(1)) / 2 + (fx(1) - fx(2)) / 2) / 8;
+ }
+ } else {
+ size = handle->dev->absmax[ABS_X] - handle->dev->absmin[ABS_X];
+ if (size == 0) size = xres;
+ list->dx += (value * xres - list->old_x[0]) / size;
+ list->old_x[0] += list->dx * size;
+ }
+ break;
case ABS_Y:
- size = handle->dev->absmax[ABS_Y] - handle->dev->absmin[ABS_Y];
- if (size == 0) size = yres;
- list->dy -= (value * yres - list->oldy) / size;
- list->oldy -= list->dy * size;
- return;
+ if (touchpad) {
+ if (list->touch) {
+ fy(0) = value;
+ if (list->pkt_count >= 2)
+ list->dy = -((fy(0) - fy(1)) / 2 + (fy(1) - fy(2)) / 2) / 8;
+ }
+ } else {
+ size = handle->dev->absmax[ABS_Y] - handle->dev->absmin[ABS_Y];
+ if (size == 0) size = yres;
+ list->dy -= (value * yres - list->old_y[0]) / size;
+ list->old_y[0] -= list->dy * size;
+ }
+ break;
}
}
@@ -149,7 +151,9 @@
switch (code) {
case BTN_TOUCH: /* Handle touchpad data */
if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit)) {
- list->finger = value;
+ list->touch = value;
+ if (!list->touch)
+ list->pkt_count = 0;
return;
}
case BTN_0:
@@ -178,6 +182,16 @@
case EV_SYN:
switch (code) {
case SYN_REPORT:
+ if (list->touch) {
+ list->pkt_count++;
+ /* Input system eats duplicate events,
+ * but we need all of them to do correct
+ * averaging so apply present one forward
+ */
+ fx(0) = fx(1);
+ fy(0) = fy(1);
+ }
+
list->ready = 1;
kill_fasync(&list->fasync, SIGIO, POLL_IN);
wake = 1;
-
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