Jetson/FAQ/BSP/Xavier Wakeup Pin

Environment

Hardware

• Jetson Xavier

Software

• JetPack 4.4 (32.4.3)

Use case

Set GPIO(STB_REQ_N/Pin L11) as wake up source to trigger OS resume.

Steps

Note: All changes are in kernel device tree.

Create GPIO key to trigger wake up signal

Add following node to hardware/nvidia/platform/t19x/galen/kernel-dts/common/tegra194-p2822-0000-a00.dtsi.

@@ -16,7 +16,7 @@
 #include "dt-bindings/input/input.h"
 #include "tegra194-audio-p2822-0000.dtsi"
 #include "tegra194-p2822-disp.dtsi"
-
+#include <dt-bindings/soc/tegra-pmc.h>
 / {
 	sdhci@3400000 {
 		mmc-ocr-mask = <0x0>;
@@ -43,4 +43,16 @@
 			gpio-key,wakeup;
 		};
 	};
+
+	gpio-keys {
+	    wakeup_key {
+		label = "WakeupKey";
+		gpios = <&tegra_main_gpio TEGRA194_MAIN_GPIO(G, 1) GPIO_ACTIVE_LOW>;
+		linux,code = <KEY_SUSPEND>;
+		gpio-key,wakeup;
+		debounce-interval = <30>;
+		nvidia,pmc-wakeup = <&tegra_pmc
+		    PMC_WAKE_TYPE_GPIO 68 PMC_TRIGGER_TYPE_HIGH>;
+	    };
+	};
 };<br>

Note:

(1) Pay attention of nvidia,pmc-wakeup property, the number 68 means wake up ID of Nano. You can find this ID from Column Y of Xavier_Module_Pinmux_Config file which comes from Jetson Download Center.

(2) If you want a key for suspend purpose, please modify linux,code propriety's value as <KEY_SUSPEND>.

Verification

Re-build device tree and re-flash to Xavier. After boot completed, exec "sudo systemctl suspend" to suspend OS. Connect that Pin and debug STB_REQ_N/Pin L11 via Dupont wire to wake up OS.