From de4d4964c29abee0be9bb06af66adb3b0ed24ffd Mon Sep 17 00:00:00 2001
From: Semih Hazar <semih.hazar@indefia.com>
Date: Wed, 18 Jul 2007 00:36:04 -0400
Subject: [PATCH] --- yaml --- r: 62169 b: refs/heads/master c:
 1d25891f3241103d14ea78236504474a138b8ada h: refs/heads/master i:   62167:
 cb0b22d23b4733b3311dedf8b8abaacc58786602 v: v3

---
 [refs]                                    |  2 +-
 trunk/drivers/input/touchscreen/ads7846.c | 15 +++++++++++++++
 trunk/include/linux/spi/ads7846.h         |  6 ++++++
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index bdfe78d2a55f..d4825e7ee0da 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e4f48861993294c27849076741eb0c090482560b
+refs/heads/master: 1d25891f3241103d14ea78236504474a138b8ada
diff --git a/trunk/drivers/input/touchscreen/ads7846.c b/trunk/drivers/input/touchscreen/ads7846.c
index 103ee6ad299e..96581d08774f 100644
--- a/trunk/drivers/input/touchscreen/ads7846.c
+++ b/trunk/drivers/input/touchscreen/ads7846.c
@@ -107,6 +107,8 @@ struct ads7846 {
 	u16			debounce_tol;
 	u16			debounce_rep;
 
+	u16			penirq_recheck_delay_usecs;
+
 	spinlock_t		lock;
 	struct hrtimer		timer;
 	unsigned		pendown:1;	/* P: lock */
@@ -553,6 +555,15 @@ static void ads7846_rx(void *ads)
 		return;
 	}
 
+	/* Maybe check the pendown state before reporting. This discards
+	 * false readings when the pen is lifted.
+	 */
+	if (ts->penirq_recheck_delay_usecs) {
+		udelay(ts->penirq_recheck_delay_usecs);
+		if (!ts->get_pendown_state())
+			Rt = 0;
+	}
+
 	/* 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
@@ -896,6 +907,10 @@ static int __devinit ads7846_probe(struct spi_device *spi)
 		ts->filter = ads7846_no_filter;
 	ts->get_pendown_state = pdata->get_pendown_state;
 
+	if (pdata->penirq_recheck_delay_usecs)
+		ts->penirq_recheck_delay_usecs =
+				pdata->penirq_recheck_delay_usecs;
+
 	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", spi->dev.bus_id);
 
 	input_dev->name = "ADS784x Touchscreen";
diff --git a/trunk/include/linux/spi/ads7846.h b/trunk/include/linux/spi/ads7846.h
index a44fa7a02bd9..334d31411629 100644
--- a/trunk/include/linux/spi/ads7846.h
+++ b/trunk/include/linux/spi/ads7846.h
@@ -24,6 +24,12 @@ struct ads7846_platform_data {
 	 */
 	u16	settle_delay_usecs;
 
+	/* If set to non-zero, after samples are taken this delay is applied
+	 * and penirq is rechecked, to help avoid false events.  This value
+	 * is affected by the material used to build the touch layer.
+	 */
+	u16	penirq_recheck_delay_usecs;
+
 	u16	x_plate_ohms;
 	u16	y_plate_ohms;