Interfacing Touchscreen (edt-ft5406) with stm32mp157c in Linux-Kernel

[ahamod3.1416]

Hi everyone,

We have developed a custom board based on stm32mp157 mpu. We have used openstlinux distribution and the branch is "kirkstone". We have interfaced edt_ft5x06 display. Display is working perfectly fine but problem arises when we try to interact with the touch. It is completely unresponsive. With "evtest" in Linux kernel I do not see any touch event. Devicetree entry for my touch-screen is following:

        touchscreen@38 {
                compatible ="edt,edt-ft5406";
                reg = <0x38>;
                interrupts = <2 2>;
                interrupt-parent = <&gpiof>;
                interrupt-controller;
                touchscreen-size-x = <480>;
                touchscreen-size-y = <800>;
                vcc-supply = <&v3v3>;
                iovcc-supply = <&v3v3>;
                status = "okay";
        };

If I look thorough the dmesg, then I get following entry:

[    2.081938] input: EP0700M12 as /devices/platform/soc/40012000.i2c/i2c-0/0-0038/input/input0

Also I have following entry for the interrupt:

 cat /proc/interrupts
           CPU0       CPU1       
 26:      22514      70457     GIC-0  27 Level     arch_timer
 30:          0          0     GIC-0  67 Level     44004000.spi
 31:          0          0     GIC-0  43 Level     dma1chan0
 32:          0          0     GIC-0  44 Level     dma1chan1
 33:          0          0     GIC-0  45 Level     dma1chan2
 34:        382          0     GIC-0  46 Level     dma1chan3
 35:          0          0     GIC-0  47 Level     dma1chan4
 36:          0          0     GIC-0  48 Level     dma1chan5
 37:          0          0     GIC-0  49 Level     dma1chan6
 38:          0          0     GIC-0  79 Level     dma1chan7
 41:          2          0     GIC-0 154 Level     58000000.dma-controller
 42:          0          0     GIC-0 124 Level     58003000.spi
 43:      68928          0     GIC-0  81 Level     mmci-pl18x (cmd)
 44:       1181          0     GIC-0 156 Level     mmci-pl18x (cmd)
 45:      11211          0     GIC-0  93 Level     eth0
 46:          1          0     GIC-0 106 Level     ohci_hcd:usb2
 47:        455          0     GIC-0 120 Level     5a001000.display-controller
 48:          0          0     GIC-0 121 Level     5a001000.display-controller
 53:         37          0  stm32-exti-h-direct  32 Level     40018000.serial
 54:          0          0  stm32-exti-h-direct  70 Level     eth0
 55:         26          0  stm32-exti-h-direct  43 Level     ehci_hcd:usb1
 56:          0          0  stm32-exti-h-direct  19 Level     5c004000.rtc
 57:         58          0  stm32-exti-h-direct  21 Level     40012000.i2c
 58:          0          0     GIC-0  64 Level     40012000.i2c
 59:          0          0  stm32gpio   2 Edge      edt-ft5406
 60:          0          0  stm32-exti-h-direct  25 Level     40015000.i2c
 61:          0          0     GIC-0 140 Level     40015000.i2c
IPI0:          0          0  CPU wakeup interrupts
IPI1:          0          0  Timer broadcast interrupts
IPI2:         36         72  Rescheduling interrupts
IPI3:       4883      77663  Function call interrupts
IPI4:          0          0  CPU stop interrupts
IPI5:          0          0  IRQ work interrupts
IPI6:          0          0  completion interrupts
Err:          0

I tried possible solutions, but could not get it to work. Can anyone tell me what is the reason for this behavior? Thanks a lot.

[debugging]

Yes, documentation for panels is often lacking. You could contact the supplier of the panel but often they developed the panel with old linux version or don't even have any Linux experience.. You can also edit the driver and put some debug messages in the code to see what is happening. check the device tree binding documentation in the kernel as well. This works for me but YMMV depending on your hardware (which seems ok as the input driver was found)

ft5x06: ft5x06@38 {

compatible = "edt,edt-ft5306";

reg = <0x38>;

interrupts = <7 IRQ_TYPE_EDGE_FALLING>;

interrupt-parent = <&gpiog>;

interrupt-controller;

reset-gpios = <&gpiog 8 GPIO_ACTIVE_LOW>;

status = "okay";

touchscreen-swapped-x-y = "true";

touchscreen-size-x = <600>;

touchscreen-size-y = <1024>;

};

[ahamod3.1416 · Accepted solution]

Thanks for your reply. I fixed it, I was referring to wrong interrupt pin. After correcting "interrupts" parameter, touch is working perfectly. Thanks again.

[debugging]

You can mark this as solved by your own answer. interesting though, because some touch drivers don't event load with the wrong interrupt pin