From: Rich.jiangyk <jyk@rock-chips.com>
Date: Sun, 19 Sep 2010 11:49:54 +0000 (+0800)
Subject: fix bug in xpt2046_ts.c, move ahead data discard.
X-Git-Tag: firefly_0821_release~11128
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c1c8e506a9aced303b0bcc4eb2eaea4df66aef80;p=firefly-linux-kernel-4.4.55.git

fix bug in xpt2046_ts.c, move ahead data discard.

The configuration for XPT2046 TS driver with CALIBRATION is "XPT2046 based touchscreens: XPT2046 SPI Interface".
In this modification,  the first raw data is discarded before processed, so that it can work on IT50.
---

diff --git a/drivers/input/touchscreen/xpt2046_ts.c b/drivers/input/touchscreen/xpt2046_ts.c
index 3b2d2b84fc30..0bc38b8bc676 100755
--- a/drivers/input/touchscreen/xpt2046_ts.c
+++ b/drivers/input/touchscreen/xpt2046_ts.c
@@ -394,6 +394,14 @@ static int xpt2046_debounce(void *xpt, int data_idx, int *val)
 		abs(ts->last_read - *val),ts->debounce_tol,
 		ts->read_rep,ts->debounce_rep);
 	
+	/* discard the first sample. */
+	 //on info_it50, the top-left area(1cmx1cm top-left square ) is not responding cause the first sample is invalid, @sep 17th
+	if(!ts->read_cnt)
+	{
+		//udelay(100);
+		ts->read_cnt++;
+		return XPT2046_FILTER_REPEAT;
+	}
 	if(*val == 4095 || *val == 0)
 	{
 		ts->read_cnt = 0;
@@ -403,11 +411,12 @@ static int xpt2046_debounce(void *xpt, int data_idx, int *val)
 		return XPT2046_FILTER_IGNORE;
 	}
 	/* discard the first sample. */
-	if(!ts->read_cnt)
+/*	if(!ts->read_cnt)
 	{
 		ts->read_cnt++;
 		return XPT2046_FILTER_REPEAT;
 	}
+move discard ahead  */
 
 	if (ts->read_cnt==1 || (abs(ts->last_read - *val) > ts->debounce_tol)) {
 		/* Start over collecting consistent readings. */