1 files changed, 54 insertions, 16 deletions

diff --git a/drivers/input/mouse/bcm5974.c b/drivers/input/mouse/bcm5974.c
index ae78bb833f62..8568211c5564 100644
--- a/drivers/input/mouse/bcm5974.c
+++ b/drivers/input/mouse/bcm5974.c
@@ -105,7 +105,7 @@ struct tp_header {
 
 /* trackpad finger structure */
 struct tp_finger {
-	__le16 origin;		/* left/right origin? */
+	__le16 origin;		/* zero when switching track finger */
 	__le16 abs_x;		/* absolute x coodinate */
 	__le16 abs_y;		/* absolute y coodinate */
 	__le16 rel_x;		/* relative x coodinate */
@@ -159,6 +159,7 @@ struct bcm5974 {
 	struct bt_data *bt_data;	/* button transferred data */
 	struct urb *tp_urb;		/* trackpad usb request block */
 	struct tp_data *tp_data;	/* trackpad transferred data */
+	int fingers;			/* number of fingers on trackpad */
 };
 
 /* logical dimensions */
@@ -172,6 +173,10 @@ struct bcm5974 {
 #define SN_WIDTH	100		/* width signal-to-noise ratio */
 #define SN_COORD	250		/* coordinate signal-to-noise ratio */
 
+/* pressure thresholds */
+#define PRESSURE_LOW	(2 * DIM_PRESSURE / SN_PRESSURE)
+#define PRESSURE_HIGH	(3 * PRESSURE_LOW)
+
 /* device constants */
 static const struct bcm5974_config bcm5974_config_table[] = {
 	{
@@ -273,32 +278,65 @@ static int report_tp_state(struct bcm5974 *dev, int size)
 	const struct tp_finger *f = dev->tp_data->finger;
 	struct input_dev *input = dev->input;
 	const int fingers = (size - 26) / 28;
-	int p = 0, w, x, y, n = 0;
+	int raw_p, raw_w, raw_x, raw_y;
+	int ptest = 0, origin = 0, nmin = 0, nmax = 0;
+	int abs_p = 0, abs_w = 0, abs_x = 0, abs_y = 0;
 
 	if (size < 26 || (size - 26) % 28 != 0)
 		return -EIO;
 
+	/* always track the first finger; when detached, start over */
 	if (fingers) {
-		p = raw2int(f->force_major);
-		w = raw2int(f->size_major);
-		x = raw2int(f->abs_x);
-		y = raw2int(f->abs_y);
-		n = p > 0 ? fingers : 0;
+		raw_p = raw2int(f->force_major);
+		raw_w = raw2int(f->size_major);
+		raw_x = raw2int(f->abs_x);
+		raw_y = raw2int(f->abs_y);
 
 		dprintk(9,
-			"bcm5974: p: %+05d w: %+05d x: %+05d y: %+05d n: %d\n",
-			p, w, x, y, n);
+			"bcm5974: raw: p: %+05d w: %+05d x: %+05d y: %+05d\n",
+			raw_p, raw_w, raw_x, raw_y);
+
+		ptest = int2bound(&c->p, raw_p);
+		origin = raw2int(f->origin);
+	}
 
-		input_report_abs(input, ABS_TOOL_WIDTH, int2bound(&c->w, w));
-		input_report_abs(input, ABS_X, int2bound(&c->x, x - c->x.devmin));
-		input_report_abs(input, ABS_Y, int2bound(&c->y, c->y.devmax - y));
+	/* while tracking finger still valid, count all fingers */
+	if (ptest > PRESSURE_LOW && origin) {
+		abs_p = ptest;
+		abs_w = int2bound(&c->w, raw_w);
+		abs_x = int2bound(&c->x, raw_x - c->x.devmin);
+		abs_y = int2bound(&c->y, c->y.devmax - raw_y);
+		for (; f != dev->tp_data->finger + fingers; f++) {
+			ptest = int2bound(&c->p, raw2int(f->force_major));
+			if (ptest > PRESSURE_LOW)
+				nmax++;
+			if (ptest > PRESSURE_HIGH)
+				nmin++;
+		}
 	}
 
-	input_report_abs(input, ABS_PRESSURE, int2bound(&c->p, p));
+	if (dev->fingers < nmin)
+		dev->fingers = nmin;
+	if (dev->fingers > nmax)
+		dev->fingers = nmax;
+
+	input_report_key(input, BTN_TOOL_FINGER, dev->fingers == 1);
+	input_report_key(input, BTN_TOOL_DOUBLETAP, dev->fingers == 2);
+	input_report_key(input, BTN_TOOL_TRIPLETAP, dev->fingers > 2);
 
-	input_report_key(input, BTN_TOOL_FINGER, n == 1);
-	input_report_key(input, BTN_TOOL_DOUBLETAP, n == 2);
-	input_report_key(input, BTN_TOOL_TRIPLETAP, n > 2);
+	input_report_abs(input, ABS_PRESSURE, abs_p);
+	input_report_abs(input, ABS_TOOL_WIDTH, abs_w);
+
+	if (abs_p) {
+		input_report_abs(input, ABS_X, abs_x);
+		input_report_abs(input, ABS_Y, abs_y);
+
+		dprintk(8,
+			"bcm5974: abs: p: %+05d w: %+05d x: %+05d y: %+05d "
+			"nmin: %d nmax: %d n: %d\n",
+			abs_p, abs_w, abs_x, abs_y, nmin, nmax, dev->fingers);
+
+	}
 
 	input_sync(input);