Difficult problems of a simple device, capacitive touchscreen on ft5406
I cleaned a cloud one day and found my notes on the problem of a touch screen with a capacitive touchscreen on ft5406. This is how this article appeared, what if someone else stumbles upon something like this during development ...
I stumbled upon a problem with a capacitive touchscreen on ft5406, the touchscreen at one point just hung up and refused to continue working. Well, now more about this.
Iron: marsboard sun7i A20.
Software: uboot 2017, kernel 4.10, LUbuntu 16.04.
The essence of the problem.
, , . .. , .
, Xinput, Xorg, .
.. touchscreen xinput, (xinput), xinput test – xinput test-xi2 - , XI 2.0 (The X Input Extension 2.x), . . , , - .
, evt-ft5x06 ( ft5406) evtest, , . , , , . xserver-xorg-input-evdev , ( ft5406) , ( ) , .
, :
xserver-xorg-input-libinput
xserver-xorg-input-mtrack
/usr/share/X11/xorg.conf.d , libinput , mtrack , , touchpad, . .. , touchpad , .
.. multitouch, XI 2.0 , .
, , devicetree ( devicetree kernell , 3.11) , ...
/drivers/input/touchscreen/ edt-ft5x06.c :
static const struct edt_i2c_chip_data edt_ft5x06_data = {
...
.max_support_points = 5,
...
};
5 1. .
. , , , .
,
static irqreturn_t edt_ft5x06_ts_isr(int irq, void *dev_id)
, .
.
. , .. ( ) .