Latest revision as of 15:25, 6 June 2023

Warning: This page is designed to be used with a 'release' URL parameter.

This page is using the default release RELEASE_SUMO_V1.0_VAR-SOM-MX8X.
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VAR-SOM-MX8X 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 execute the following command:

# 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;
               };
	};

Touching the capacitive touchscreen which has the "wakeup-source" property set in its device tree node, e.g.:

       ft5x06_ts: ft5x06_ts@38 {
               status = "disabled";
               compatible = "edt,edt-ft5x06";
               reg = <0x38>;
               reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>;
               pinctrl-names = "default";
               pinctrl-0 = <&pinctrl_touch>;
               interrupt-parent = <&gpio1>;
               interrupts = <14 0>;
               touchscreen-size-x = <800>;
               touchscreen-size-y = <480>;
               touchscreen-inverted-x;
               touchscreen-inverted-y;
               wakeup-source;
       };

Pressing any key on debug console defined as wake-up source before entering suspend (see below):

$ echo enabled > /sys/devices/platform/5a090000.serial/tty/ttyLP3/power/wakeup

@@ Line 1: / Line 1: @@
 <!-- Set release according to "release" parameter in URL and use RELEASE_SUMO_V1.0_VAR-SOM-MX8X as default
---> {{#vardefine:RELEASE_PARAM|{{#urlget:release}}}} <!--
+--> {{INIT_RELEASE_PARAM|RELEASE_SUMO_V1.0_VAR-SOM-MX8X}} <!--
---> {{#lst:Yocto_Platform_Customization|{{#var:RELEASE_PARAM|RELEASE_SUMO_V1.0_VAR-SOM-MX8X}}}} <!--
+--> {{#lst:Yocto_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
---> {{PageHeader|{{#var:HARDWARE_NAME}} Suspend to RAM}}{{DocImage|category1=Yocto|category2={{#var:HARDWARE_NAME}}}}
+--> {{#lst:Debian_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
+--> {{PageHeader|{{#var:HARDWARE_NAME}} Suspend to RAM}}{{DocImage|category1=Yocto|category2=Debian}} [[category:{{#var:HARDWARE_NAME}}]]
 = Suspend to RAM =
@@ Line 18: / Line 19: @@
 {{#varexists:PAD_WAKEUP_SUPPORT|
 * Pushing a button on the board which has the properties "pad-wakeup-num" and  "pad-wakeup" set in its device tree node (under gpio related node), e.g.:
+    {{#ifeq: {{#var:HARDWARE_NAME}}|VAR-SOM-MX8|
      wakeup from direct GPIOs
      &lsio_gpio5 {
@@ Line 43: / Line 45: @@
          '''pad-wakeup = <IMX8QM_MIPI_CSI0_MCLK_OUT SC_PAD_WAKEUP_LOW_LVL 24>;'''
      };
+    |
+    wakeup from IOexpander GPIOs
+    &lsio_gpio3 {
+        /* Enable wakeup-source from all pca9534 gpio-keys*/
+        '''pad-wakeup-num = <1>;'''	/* Total number of wakeup pads in gpio3 bank */
+        /*
+         IMX8QXP_MIPI_CSI0_MCLK_OUT: PCA9534 IRQ pin id
+         SC_PAD_WAKEUP_LOW_LVL:      trigger type
+:                          PCA9534 IRQ gpio pin
+        */
+        '''pad-wakeup = <IMX8QXP_MIPI_CSI0_MCLK_OUT SC_PAD_WAKEUP_LOW_LVL 4>;'''
+    };
+    }}
 * Pressing the capacitive touch which has the properties "pad-wakeup-num" and  "pad-wakeup" set in its device tree node (under touch IRQ gpio related node), e.g.:
+    {{#ifeq: {{#var:HARDWARE_NAME}}|VAR-SOM-MX8|
      &lsio_gpio1 {
          /* Enable wakeup-source from Capacitive touch */
@@ Line 55: / Line 70: @@
          '''pad-wakeup = <IMX8QM_LVDS0_GPIO01 SC_PAD_WAKEUP_LOW_LVL 5>;'''
      };
+    |
+    &lsio_gpio0 {
+        /* Enable wakeup-source from Capacitive touch */
+        '''pad-wakeup-num = <1>;''' /* Total number of wakeup pads in gpio0 bank */
+        /*
+         IMX8QXP_UART1_CTS_B:   Touch IRQ pin id
+         SC_PAD_WAKEUP_LOW_LVL: trigger type
+:                    Touch IRQ gpio pin
+        */
+        '''pad-wakeup = <IMX8QXP_UART1_CTS_B SC_PAD_WAKEUP_LOW_LVL 24>;'''
+    };
+    }}
 |
 * Pushing a button on the board which has the boolean property "wakeup-source" set in its device tree node (under gpio_keys), e.g.:
@@ Line 92: / Line 119: @@
 * Pressing any key on debug console defined as wake-up source before entering suspend (see below):<br>
   {{#varexists:UART_CONSOLE_PATH|
-  <pre># echo enabled > {{#var:UART_CONSOLE_PATH}}</pre>
+  $ echo enabled > {{#var:UART_CONSOLE_PATH}}
   |
   {{#ifeq: {{#var:HARDWARE_NAME}}|VAR-SOM-MX8X|
-  <pre># echo enabled > /sys/devices/platform/5a090000.serial/tty/ttyLP3/power/wakeup</pre>
+  $ echo enabled > /sys/devices/platform/5a090000.serial/tty/ttyLP3/power/wakeup
   |
-  <pre># echo enabled > /sys/devices/platform/5a060000.serial/tty/ttyLP0/power/wakeup</pre>
+  $ echo enabled > /sys/devices/platform/5a060000.serial/tty/ttyLP0/power/wakeup
 }}
 }}

MX8 suspend: Difference between revisions

Latest revision as of 15:25, 6 June 2023

Suspend to RAM

Wake up