i.MX ProcessorsのトピックRe: GPIO Wake up

GPIO Wake up

cduarte0306 — Sat, 16 Mar 2024 05:05:42 GMT

Hi all,

I am working on a device based on an IMX8MP which uses a Trigger pin as a wake up pin when the unit is asleep, and a regular pin from user space when awake.

The pin is bound by the following functions

int ret = 0; ret = system("echo gpio-keys > /sys/bus/platform/drivers/gpio-keys/unbind"); if (ret != 0) { std::cerr << "Failed to set direction for GPIO pin 6." << std::endl; return 0; } ret = system("echo 6 > /sys/class/gpio/export"); if (ret != 0) { std::cerr << "Failed to set direction for GPIO pin 6." << std::endl; return 0; } ret = system("echo out > /sys/class/gpio/gpio6/direction"); if (ret != 0) { std::cerr << "Failed to set direction for GPIO pin 6." << std::endl; return 0; } ret = system("echo 1 > /sys/class/gpio/gpio6/value"); if (ret != 0) { std::cerr << "Failed to set direction for GPIO pin 6." << std::endl; return 0; } return 1;

My problem is, despite my DTS settings, the pin is still waking up from both edges (falling and rising), when it should only wake up from a rising edge.

Would anyone happen to know why?

gpio-keys { compatible = "gpio-keys"; pinctrl-0 = <&pinctrl_gpio_keys>; pinctrl-names = "default"; trigger_in { label = "TRIGGER IN_PIN"; gpios = <&gpio1 6 GPIO_ACTIVE_LOW>; linux,code = <KEY_WAKEUP>; debounce-interval = <10>; wakeup-source; }; }; pinctrl_gpio_keys: gpiokeysgrp { fsl,pins = < MX8MP_IOMUXC_GPIO1_IO06__GPIO1_IO06 0x19 >; };

I am using kernel version 6.1

Re: GPIO Wake up

Manuel_Salas — Tue, 19 Mar 2024 19:24:28 GMT

Hello @cduarte0306

Could you please try to add tou your dts:

interrupt-parent = <&gpio1>; interrupts = <6 IRQ_TYPE_EDGE_RISING>;

And let me know if that works.

Best regards.

Salas.

Re: GPIO Wake up

cduarte0306 — Tue, 19 Mar 2024 19:43:30 GMT

Would this be under the gpio-keys node?

Carlos

Re: GPIO Wake up

Manuel_Salas — Tue, 19 Mar 2024 19:51:03 GMT

Hello,

gpio-keys { compatible = "gpio-keys"; pinctrl-0 = <&pinctrl_gpio_keys>; pinctrl-names = "default"; trigger_in { label = "TRIGGER IN_PIN"; gpios = <&gpio1 6 GPIO_ACTIVE_LOW>; linux,code = <KEY_WAKEUP>; debounce-interval = <10>; interrupt-parent = <&gpio1>; interrupts = <6 IRQ_TYPE_EDGE_RISING>; wakeup-source; }; };

Please try and let me know.

Best regards.

Salas.

Re: GPIO Wake up

cduarte0306 — Wed, 20 Mar 2024 15:26:29 GMT

I tried this and it works when I click the button. I should've mentioned that the pin's end of the connection is inverted form the button click by an optocoupler, meaning that the unit should wake up when the button is released ( a rising edge at the optocoupler, a falling edge at the SoM's Pin)

I tried changing it to

gpio-keys { compatible = "gpio-keys"; pinctrl-0 = <&pinctrl_gpio_keys>; pinctrl-names = "default"; trigger_in { label = "TRIGGER IN_PIN"; gpios = <&gpio1 6 GPIO_ACTIVE_LOW>; linux,code = <KEY_WAKEUP>; debounce-interval = <10>; interrupt-parent = <&gpio1>; interrupts = <6 IRQ_TYPE_EDGE_FALLING>; wakeup-source; }; };

And it was waking on both edges once more

Re: GPIO Wake up

cduarte0306 — Sat, 06 Apr 2024 02:30:02 GMT

I should let you know this solution is not working for some reason.