Re: [Letux-kernel] [PATCH v3 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation

From: Christ van Willegen
Date: Fri Sep 30 2016 - 12:23:47 EST


Hi,

I saw this earlier, but didn't think it important to mention, but:


On Fri, Sep 23, 2016 at 2:41 PM, H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> wrote:

> diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c
> index 5d0cd51..9a11509 100644
> --- a/drivers/input/touchscreen/tsc2007.c
> +++ b/drivers/input/touchscreen/tsc2007.c

> + /* scale ADC values to desired output range */
> + sx = (ts->prop.max_x * (tc.x - ts->min_x))
> + / (ts->max_x - ts->min_x);
> + sy = (ts->prop.max_y * (tc.y - ts->min_y))
> + / (ts->max_y - ts->min_y);
> + rt = (input->absinfo[ABS_PRESSURE].maximum * rt) /
> + ts->max_rt;

If ts->max_rt is zero, or ts->max_x == ts->min_x, or ts->max_y ==
ts->min_y, these yield a division by zero error.

Ofcourse, this is under control of the DT-maintainer(s) of the device
(if I'm not mistaking), but throwing an error on DT parse if (one of)
these condition(s) is met yields better info to the DT-maintainer than
a /0 error...

If you (or others) agree, could you add this to the patch?

Regards,

Christ van Willegen