From 540792753c292bce53f42eb7b8fb3d3510f57e00 Mon Sep 17 00:00:00 2001 From: Markus Pargmann Date: Sat, 9 Mar 2013 15:21:33 -0800 Subject: [PATCH] Input: wm9712 - fix wrong pen up readings MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Often a reading can be wrong. This patch assures that this is really a pen up event and not a false reading. Based on wm9712: pen up by Teresa Gámez and Christian Hemp. Signed-off-by: Markus Pargmann Acked-by: Mark Brown Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/wm9712.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/input/touchscreen/wm9712.c b/drivers/input/touchscreen/wm9712.c index a983da1744e8..3b4eed4b8690 100644 --- a/drivers/input/touchscreen/wm9712.c +++ b/drivers/input/touchscreen/wm9712.c @@ -302,8 +302,12 @@ static int wm9712_poll_sample(struct wm97xx *wm, int adcsel, int *sample) } if (wants_pen && !(*sample & WM97XX_PEN_DOWN)) { - wm->pen_probably_down = 0; - return RC_PENUP; + /* Sometimes it reads a wrong value the first time. */ + *sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); + if (!(*sample & WM97XX_PEN_DOWN)) { + wm->pen_probably_down = 0; + return RC_PENUP; + } } return RC_VALID; -- GitLab