i.MX ProcessorsのトピックRe: Wakeup the system from gpio interrupt

Wakeup the system from gpio interrupt

sharmila_devada — Mon, 21 Oct 2019 04:37:10 GMT

Hi,

I am using pcf2127 rtc module in my custom board. The GPIO3_16 is used for rtc alarm interrupt. Now I have to suspend the module and when rtc alarm interrupt comes, it should wake up. I am using below command for suspending the system

echo mem > /sys/power/state

When rtc alarm interrupt comes , the system is not waking up. The configuration I have made in my dts file is as below

gpio-keys {

compatible = "gpio-keys";

wakeup {

label = "wakeup gpio";

gpios = <&gpio3 16 GPIO_ACTIVE_LOW>;

linux,code = <29>;

gpio-key,wakeup;

};

But the system is not coming out of suspend mode. Please tell me where I am going wrong.

Thank You,

Regards,

Sharmila

Re: Wakeup the system from gpio interrupt

igorpadykov — Mon, 21 Oct 2019 06:54:43 GMT

Hi Sharmilla

one can check if gpio wakeup linux commits were implemented as mentioned below

Wakeup Source Configuration iMX8QXP/DX

 dts example:
gpio4: gpio@5d0c0000 {
     compatible = "fsl,imx8qm-gpio", "fsl,imx35-gpio";
     reg = <0x0 0x5d0c0000 0x0 0x10000>;
     interrupts = <GIC_SPI 140 IRQ_TYPE_LEVEL_HIGH>;
     gpio-controller;
     #gpio-cells = <2>;
     power-domains = <&pd_lsio_gpio4>;
     interrupt-controller;
     #interrupt-cells = <2>;
     /* total pad wakeup number in gpio4 */
     pad-wakeup-num = <1>;
     /* SC_P_USDHC1_CD_B, SC_PAD_WAKEUP_LOW_LVL, LINE 22 */
     pad-wakeup = <27 4 22>;
};

Best regards
igor
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Re: Wakeup the system from gpio interrupt

sharmila_devada — Mon, 21 Oct 2019 09:53:16 GMT

Hi,

I have made the above changes in my dtsi file and the result is same. Please tell me do I need to add any other changes such that my system will wake from suspend mode when rtc interrupt comes.

Regards,

Sharmila

Re: Wakeup the system from gpio interrupt

igorpadykov — Mon, 21 Oct 2019 10:33:20 GMT

Hi Sharmila

also one can consider onoff pin as wake source:

    sc_pwrkey: sc-powerkey {
       compatible = "fsl,imx8-pwrkey";
       linux,keycode = <KEY_POWER>;
       wakeup-source;
   };

fsl-imx8dx.dtsi\freescale\dts\boot\arm64\arch - linux-imx - i.MX Linux kernel

Best regards
igor

Re: Wakeup the system from gpio interrupt

sharmila_devada — Mon, 21 Oct 2019 11:34:07 GMT

Hi igor,

Thank you for your support.

Our hardware doesn't have Power key option. Please tell me how to wake up the system using rtc interrupt.

Regards,

Sharmila

Re: Wakeup the system from gpio interrupt

igorpadykov — Mon, 21 Oct 2019 13:46:43 GMT

Hi Sharmila

this part is preproduction part and unfortunately has not full support.

Suggest to proceed with extended support of Commercial Support and Engineering Services | NXP

Best regards
igor

Re: Wakeup the system from gpio interrupt

sharmila_devada — Wed, 23 Oct 2019 12:41:02 GMT

Hi igor,

I have created suspend and resume function in my rtc driver as below

static int pcf2127_rtc_suspend(struct device *dev)
{
struct pcf2127 *pdata = dev_get_drvdata(dev);

if (device_may_wakeup(dev))
{

               printk("pcf2127_rtc_suspend..\r\n");
                enable_irq_wake(irqNumber);
        }

return 0;
}

static int pcf2127_rtc_resume(struct device *dev)
{
struct pcf2127 *pdata = dev_get_drvdata(dev);

if (device_may_wakeup(dev))
{

               printk("pcf2127_rtc_suspend..\r\n");
                disable_irq_wake(irqNumber);
        }

return 0;
}

Note : irqNumber is IRQ of GPIO which I got from gpio_to_irq(gpio_number).

when I suspend the system using echo mem > /sys/power/state command I am getting below prints

root@imx8dx_ccu:/usr/bin/ccu# echo mem > /sys/power/state
[   25.205302] PM: suspend entry (deep)
[   25.208888] PM: Syncing filesystems ... done.
[   25.242558] Freezing user space processes ... (elapsed 0.001 seconds) done.
[   25.250873] OOM killer disabled.
[   25.254121] Freezing remaining freezable tasks ... (elapsed 0.007 seconds) done.
[   25.273048] pcf2127_rtc_read_time..
[   25.277080] pcf2127_rtc_suspend..
[   25.280479] irq_set_irq_wake..
[   25.283642] irq_set_irq_wake..
[   25.288329] PM: suspend devices took 0.016 seconds
[   25.295436] Disabling non-boot CPUs ...
[   25.313505] CPU1: shutdown
[   25.316298] psci: CPU1 killed.

But system is not waking up when alarm interrupt comes.

Please provide some input.

Regards,

Sharmila

Re: Wakeup the system from gpio interrupt

mrcryo — Wed, 13 Nov 2019 15:27:45 GMT

Hi Sharmila,

To use gpio as a wakeup source, one needed to configure pad-wakeup property for gpio node.

In your case it could be like:

/ {

...

gpio-keys {

compatible = "gpio-keys";

wakeup {

label = "wakeup gpio";

gpios = <&gpio3 16 GPIO_ACTIVE_LOW>;

linux,code = <KEY_WAKEUP>;

wakeup-source;

};

...

};

&gpio3 {

/* total pad wakeup number in gpio3 */

pad-wakeup-num = <1>;

/* SC_P_QSPI0A_SCLK, SC_PAD_WAKEUP_LOW_LVL, LINE 16 */

/*

* See include/dt-bindings/pinctrl/pads-imx8qxp.h

* include/soc/imx8/sc/svc/pad/api.h

* and drivers/gpio/gpio-mxc.c

*/ pad-wakeup = <163 4 16>; };

We're able to wake our custom module up with gpio using similar config.

Re: Wakeup the system from gpio interrupt

sharmila_devada — Thu, 14 Nov 2019 05:48:57 GMT

Thank you,

After enabling pad wakeup, the wake up the system using gpio interrupt is working fine.