1 files changed, 41 insertions, 39 deletions

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index 11979be3358..b18c63a3f2a 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -378,11 +378,8 @@ static struct attribute_group ads7845_attr_group = {
 static void ads7846_rx(void *ads)
 {
 	struct ads7846		*ts = ads;
-	struct input_dev	*input_dev = ts->input;
 	unsigned		Rt;
-	unsigned		sync = 0;
 	u16			x, y, z1, z2;
-	unsigned long		flags;
 
 	/* ads7846_rx_val() did in-place conversion (including byteswap) from
 	 * on-the-wire format as part of debouncing to get stable readings.
@@ -396,7 +393,7 @@ static void ads7846_rx(void *ads)
 	if (x == MAX_12BIT)
 		x = 0;
 
-	if (likely(x && z1 && !device_suspended(&ts->spi->dev))) {
+	if (likely(x && z1)) {
 		/* compute touch pressure resistance using equation #2 */
 		Rt = z2;
 		Rt -= z1;
@@ -412,52 +409,44 @@ static void ads7846_rx(void *ads)
 	 * once more the measurement
 	 */
 	if (ts->tc.ignore || Rt > ts->pressure_max) {
+#ifdef VERBOSE
+		pr_debug("%s: ignored %d pressure %d\n",
+			ts->spi->dev.bus_id, ts->tc.ignore, Rt);
+#endif
 		hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
 			      HRTIMER_REL);
 		return;
 	}
 
-	/* NOTE:  "pendown" is inferred from pressure; we don't rely on
-	 * being able to check nPENIRQ status, or "friendly" trigger modes
-	 * (both-edges is much better than just-falling or low-level).
-	 *
-	 * REVISIT:  some boards may require reading nPENIRQ; it's
-	 * needed on 7843.  and 7845 reads pressure differently...
+	/* NOTE: We can't rely on the pressure to determine the pen down
+	 * state, even this controller has a pressure sensor.  The pressure
+	 * value can fluctuate for quite a while after lifting the pen and
+	 * in some cases may not even settle at the expected value.
 	 *
-	 * REVISIT:  the touchscreen might not be connected; this code
-	 * won't notice that, even if nPENIRQ never fires ...
+	 * The only safe way to check for the pen up condition is in the
+	 * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
 	 */
-	if (!ts->pendown && Rt != 0) {
-		input_report_key(input_dev, BTN_TOUCH, 1);
-		sync = 1;
-	} else if (ts->pendown && Rt == 0) {
-		input_report_key(input_dev, BTN_TOUCH, 0);
-		sync = 1;
-	}
-
 	if (Rt) {
-		input_report_abs(input_dev, ABS_X, x);
-		input_report_abs(input_dev, ABS_Y, y);
-		sync = 1;
-	}
+		struct input_dev *input = ts->input;
 
-	if (sync) {
-		input_report_abs(input_dev, ABS_PRESSURE, Rt);
-		input_sync(input_dev);
-	}
-
-#ifdef	VERBOSE
-	if (Rt || ts->pendown)
-		pr_debug("%s: %d/%d/%d%s\n", ts->spi->dev.bus_id,
-			x, y, Rt, Rt ? "" : " UP");
+		if (!ts->pendown) {
+			input_report_key(input, BTN_TOUCH, 1);
+			ts->pendown = 1;
+#ifdef VERBOSE
+			dev_dbg(&ts->spi->dev, "DOWN\n");
 #endif
+		}
+		input_report_abs(input, ABS_X, x);
+		input_report_abs(input, ABS_Y, y);
+		input_report_abs(input, ABS_PRESSURE, Rt);
 
-	spin_lock_irqsave(&ts->lock, flags);
+		input_sync(input);
+#ifdef VERBOSE
+		dev_dbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt);
+#endif
+	}
 
-	ts->pendown = (Rt != 0);
 	hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD), HRTIMER_REL);
-
-	spin_unlock_irqrestore(&ts->lock, flags);
 }
 
 static int ads7846_debounce(void *ads, int data_idx, int *val)
@@ -553,14 +542,27 @@ static int ads7846_timer(struct hrtimer *handle)
 
 	spin_lock_irq(&ts->lock);
 
-	if (unlikely(ts->msg_idx && !ts->pendown)) {
+	if (unlikely(!ts->get_pendown_state() ||
+		     device_suspended(&ts->spi->dev))) {
+		if (ts->pendown) {
+			struct input_dev *input = ts->input;
+
+			input_report_key(input, BTN_TOUCH, 0);
+			input_report_abs(input, ABS_PRESSURE, 0);
+			input_sync(input);
+
+			ts->pendown = 0;
+#ifdef VERBOSE
+			dev_dbg(&ts->spi->dev, "UP\n");
+#endif
+		}
+
 		/* measurement cycle ended */
 		if (!device_suspended(&ts->spi->dev)) {
 			ts->irq_disabled = 0;
 			enable_irq(ts->spi->irq);
 		}
 		ts->pending = 0;
-		ts->msg_idx = 0;
 	} else {
 		/* pen is still down, continue with the measurement */
 		ts->msg_idx = 0;