SK-AM62B: How to configure the RTC interrupt to serve as a wake-up source

Hello Sean, 

Thank you for the query.

I am trying to understand the use case.

Is this s general query or have you made the connections and seeing some issues?

Regards,

Sreenivasa

Hi Sreenivasa,

I have successfully woken the operating system from s2idle via the gpio-keys subsystem. like this:

  buttons0 {
                compatible = "gpio-keys";
                pinctrl-names = "default";
                pinctrl-0 = <&push_button_pins_default>;

                push-button {
                        label = "GPIO Key USER1";
                        linux,code = <KEY_WAKEUP>;
                        gpios = <&main_gpio0 12 GPIO_ACTIVE_LOW>;
                        wakeup-source;
                };
        };

My next task is to add the RTC as a wakeup source. The first thing that confuses me is what is the difference between EXTINTn and GPIO1_31. Also, if EXTINTn is the right choice, what should the interrupt number be?

Finally, I noticed that my RTC is edge-triggered. I conducted a small experiment to change the parameters from IRQ_TYPE_LEVEL_HIGH to IRQ_TYPE_EDGE_FALLING on the i2c node in the device tree. After booting into the OS and checking /proc/interrupts, I observed that the entry for i2c1 disappeared. This is one thing I am concerned about.

Thanks,

Sean

Hello Sean, 

Thank you for the inputs,

EXTINTn is just a dedicated interrupt pin using an open drain buffer.

SeanHC Lin said:

My next task is to add the RTC as a wakeup source. The first thing that confuses me is what is the difference between EXTINTn and GPIO1_31. Also, if EXTINTn is the right choice, what should the interrupt number be?

SeanHC Lin said:

Finally, I noticed that my RTC is edge-triggered. I conducted a small experiment to change the parameters from IRQ_TYPE_LEVEL_HIGH to IRQ_TYPE_EDGE_FALLING on the i2c node in the device tree. After booting into the OS and checking /proc/interrupts, I observed that the entry for i2c1 disappeared. This is one thing I am concerned about.

I will have to assign to a software expert. If you could add any additional details that would help as i assign to the expert.

Regards,

Sreenivasa

Hi Sreenivasa,

Yes, the EXTINTn signal is routed to the GIC500 as SPI 256.

Now, I can catch interrupts.

Note: I am referring to the settings of the device tree properties in k3-am625-beagleplay.dts.

&main_i2c0 {

    tps65219: pmic@30 {
        pinctrl-names = "default";
        pinctrl-0 = <&pmic_irq_pins_default>;
        interrupt-parent = <&gic500>;
        interrupts = <GIC_SPI 224 IRQ_TYPE_LEVEL_HIGH>;
        interrupt-controller;
        #interrupt-cells = <1>;
    };
};

thanks for your help

Sean