fix M1 GPS power control

zephcore/adapters/gps/ZephyrGPSManager.cpp

@@ -749,9 +749,18 @@ static void gps_power_control(bool on, bool keep_vrtc = false)
 #if HAS_GPS_RESET
 		/* Hold GPS in reset during power-off — matches Arduino sleep_gps()/stop_gps().
 		 * Ensures chip sees RESET asserted when GPS_EN goes HIGH on next
-		 * power-on, preventing uncontrolled startup before the reset pulse. */
+		 * power-on, preventing uncontrolled startup before the reset pulse.
+		 * Configure-on-first-use (mirrors the GPS_EN pin below): on a
+		 * boot-with-GPS-off the power-on path never ran, so the pin isn't an
+		 * output yet — gpio_pin_set_dt() alone would leave it floating instead
+		 * of asserting reset. GPIO_OUTPUT_ACTIVE drives the active (asserted)
+		 * level directly. */
 		if (gpio_is_ready_dt(&gps_reset_gpio)) {
-			gpio_pin_set_dt(&gps_reset_gpio, 1);
+			if (!gps_gpio_configured) {
+				gpio_pin_configure_dt(&gps_reset_gpio, GPIO_OUTPUT_ACTIVE);
+			} else {
+				gpio_pin_set_dt(&gps_reset_gpio, 1);
+			}
 		}
 #endif
 

zephcore/boards/nrf52840/thinknode_m1/thinknode_m1.dts

@@ -49,6 +49,7 @@
 		watchdog0 = &wdt0;
 		buzzer = &buzzer;
 		gps-enable = &gps_enable_pin;
+		gps-reset = &gps_reset_pin;
 	};
 
 	/* ---- LEDs (active-high, matches MeshCore LED_STATE_ON=HIGH) ---- */
@@ -106,13 +107,21 @@
 		regulator-boot-on;
 	};
 
-	/* LoRa radio power enable — must be HIGH before SX1262 can communicate */
-	lora_pwr_enable: lora-pwr-enable {
-		compatible = "regulator-fixed";
-		regulator-name = "lora-pwr-enable";
-		enable-gpios = <&gpio1 5 GPIO_ACTIVE_HIGH>;
-		regulator-boot-on;
-		startup-delay-us = <10000>;
+	/* GPS hardware reset (P1.05, active-LOW).
+	 * This pin is the Air530Z RESET line — NOT a LoRa power rail (the SX1262
+	 * is fed by pwr_enable P0.12 + tcxo_enable P0.21). Confirmed against
+	 * Arduino MeshCore (PIN_GPS_RESET=37=P1.05) and Meshtastic (PIN_GPS_REINIT).
+	 * Asserted (pin LOW) on standby/off to halt the module cleanly: the CASIC
+	 * chip ignores UART/standby-pin sleep, so holding reset is the only reliable
+	 * way to stop it drawing. Released (pin HIGH) after GPS_EN on wake.
+	 * (Previously mislabelled lora_pwr_enable + regulator-boot-on, which pinned
+	 * reset permanently de-asserted so the GPS never powered down.) */
+	gps_rst: gps-reset {
+		compatible = "gpio-leds";
+		gps_reset_pin: gps_reset {
+			gpios = <&gpio1 5 GPIO_ACTIVE_LOW>;
+			label = "GPS Reset";
+		};
 	};
 
 	/* External TCXO power enable — SX1262 DIO3 provides reference voltage,