DART-MX8M suspend

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Suspend to RAM

Suspend to RAM

This state offers significant power savings as everything in the system is put into a low-power state, except for memory, which is placed into the self-refresh mode to retain its contents.


To suspend to RAM:

$ pm-suspend

Wake up

There are many possible ways to wake up from suspend.
A few examples:
- Pushing the ON/OFF button (when present on the board)
- Pushing a button on the board which has the boolean property "wakeup-source" set in its device tree node (under gpio_keys), e.g.:

	gpio-keys {
		compatible = "gpio-keys";
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_gpio_keys>;
               ...
               back {
                       label = "Back";
                       gpios = <&gpio4 6 GPIO_ACTIVE_LOW>;
                       linux,code = <KEY_BACK>;
                       wakeup-source;
               };
	};

Measuring current consumption in suspend

To measure the current remove resistor R15 and connect ampere meter instead.
It is recommended to boot from eMMC to get accurate measurement.