From 84005eb5ea2939d448047fcf6924b3b9b6ed974d Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Tue, 17 May 2011 09:31:01 -0700 Subject: [PATCH] Input: tsc2007 - add max_rt parameter to platform data Finger touch events or very quick stylus events on low-quality panels can cause the tsc2007 to read bogus values. Looking at oscilloscope snapshots, this seems to be caused by the touch event disappearing during the measurements. These bogus values result in misclicks, where the X and Y values deviate from the real position. Most of these misclicks can be filtered out by setting a low enough threshold for the maximum resistance (which is loosely the inverse of the pressure) allowed to consider a set of values valid. Since this behaviour is largely dependent on the type and quality of the panel, this commit introduces the max_rt parameter. The default value is kept at MAX_12BIT. Signed-off-by: Thierry Reding Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/tsc2007.c | 4 +++- include/linux/i2c/tsc2007.h | 1 + 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c index df4ae35..8c48a91 100644 --- a/drivers/input/touchscreen/tsc2007.c +++ b/drivers/input/touchscreen/tsc2007.c @@ -75,6 +75,7 @@ struct tsc2007 { u16 model; u16 x_plate_ohms; + u16 max_rt; bool pendown; int irq; @@ -185,7 +186,7 @@ static void tsc2007_work(struct work_struct *work) tsc2007_read_values(ts, &tc); rt = tsc2007_calculate_pressure(ts, &tc); - if (rt > MAX_12BIT) { + if (rt > ts->max_rt) { /* * Sample found inconsistent by debouncing or pressure is * beyond the maximum. Don't report it to user space, @@ -294,6 +295,7 @@ static int __devinit tsc2007_probe(struct i2c_client *client, ts->model = pdata->model; ts->x_plate_ohms = pdata->x_plate_ohms; + ts->max_rt = pdata->max_rt ? : MAX_12BIT; ts->get_pendown_state = pdata->get_pendown_state; ts->clear_penirq = pdata->clear_penirq; diff --git a/include/linux/i2c/tsc2007.h b/include/linux/i2c/tsc2007.h index c6361fb..d95f113 100644 --- a/include/linux/i2c/tsc2007.h +++ b/include/linux/i2c/tsc2007.h @@ -6,6 +6,7 @@ struct tsc2007_platform_data { u16 model; /* 2007. */ u16 x_plate_ohms; + u16 max_rt; /* max. resistance above which samples are ignored */ int (*get_pendown_state)(void); void (*clear_penirq)(void); /* If needed, clear 2nd level -- 2.7.4