Correct xpt2046_cbn_ts bug on IT50

On IT50 board, the touch screen sends 4095 invalid message for first raw data sample, especially
for the top-left corner.
The modification discards the first sample before processing it, which correct the bug and solve
the problem on IT50. This won't affect other boards.
NOTE: mod by srt, commit by jyk

diff --git a/drivers/input/touchscreen/xpt2046_cbn_ts.c b/drivers/input/touchscreen/xpt2046_cbn_ts.c
index 8e34fadbb5109f6525418ce7e072fadb26b129b7..ca1bd122a7e347f0d20457c99987690580d399e4 100644 (file)
--- a/drivers/input/touchscreen/xpt2046_cbn_ts.c
+++ b/drivers/input/touchscreen/xpt2046_cbn_ts.c
@@ -386,21 +386,26 @@ 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;
                ts->last_read = 0;
                memset(average_val,0,sizeof(average_val));
                xpt2046printk("***>%s:*val == 4095 || *val == 0\n",__FUNCTION__);
+
                return XPT2046_FILTER_IGNORE;
+
        }
-       /* discard the first sample. */
-       if(!ts->read_cnt)
-       {
-               //udelay(100);
-               ts->read_cnt++;
-               return XPT2046_FILTER_REPEAT;
-       }
+
 
        if (ts->read_cnt==1 || (abs(ts->last_read - *val) > ts->debounce_tol)) {
                /* Start over collecting consistent readings. */