From 95c992d96612671d6c71231ffae6ccbc7b64d0ba Mon Sep 17 00:00:00 2001
From: pelgraine <140762863+pelgraine@users.noreply.github.com>
Date: Sat, 2 May 2026 10:19:37 +1000
Subject: [PATCH] Hibernate now enters true deep sleep on T-Deck Pro.

UITask shutdown (already occurs/unchanged):
1. BLE disabled (_serial->disable()).
2. WiFi disconnected + WIFI_OFF.
3. 4G modem shutdown().
4. GPS power cut (PIN_GPS_EN LOW).
5. LoRa radio powerOff() (standby mode).
6. Display turnOff().

TDeckBoard::powerOff() (new):
7. btStop() -- BLE controller stop.
8. Peripheral power OFF (PIN_PERF_POWERON LOW) -- keyboard, BQ27220, sensors.
9. LoRa module power OFF (P_LORA_EN LOW) -- cuts power entirely.
10. Hold LoRa NSS high (prevents SX1262 drawing current from floating CS).
11. esp_deep_sleep_start() -- CPU halts, ~10-40uA.

Wake (reset button or USB power-on):
12. ESP32-S3 cold boots.
13. TDeckBoard::begin() runs: peripheral power ON, I2C init, LoRa power ON, NSS hold released.
14. App starts fresh -- prefs/contacts/messages load from flash.

No LoRa wake during hibernate -- the device is truly off. Only a hardware
reset (reset button) or USB power-on wakes the device.
---
 variants/lilygo_tdeck_pro/TDeckBoard.h | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/variants/lilygo_tdeck_pro/TDeckBoard.h b/variants/lilygo_tdeck_pro/TDeckBoard.h
index c9a09b29..ab469249 100644
--- a/variants/lilygo_tdeck_pro/TDeckBoard.h
+++ b/variants/lilygo_tdeck_pro/TDeckBoard.h
@@ -30,10 +30,28 @@ public:
   void begin();
 
   void powerOff() override {
-    // Stop Bluetooth before power off
-    btStop();
-    // Don't call parent or enterDeepSleep - let normal shutdown continue
-    // Display will show "hibernating..." text
+    // True hibernate: deep sleep with no software wake sources.
+    // Only a hardware reset (reset button) or USB power-on wakes the device.
+    // BLE, WiFi, 4G, GPS, and LoRa are already shut down by UITask
+    // before this method is called.
+
+    btStop();  // Belt and suspenders -- BLE controller stop
+
+    // Cut power to peripherals (keyboard, BQ27220, sensors)
+    pinMode(PIN_PERF_POWERON, OUTPUT);
+    digitalWrite(PIN_PERF_POWERON, LOW);
+
+    // Cut power to LoRa module (radio already in standby from radio_driver.powerOff)
+    #ifdef P_LORA_EN
+      digitalWrite(P_LORA_EN, LOW);
+    #endif
+
+    // Hold LoRa NSS high to prevent SX1262 drawing current from floating CS
+    rtc_gpio_hold_en((gpio_num_t)P_LORA_NSS);
+
+    // Enter deep sleep with no wake sources -- only hardware reset wakes
+    esp_sleep_pd_config(ESP_PD_DOMAIN_RTC_PERIPH, ESP_PD_OPTION_OFF);
+    esp_deep_sleep_start();
   }
 
   void enterDeepSleep(uint32_t secs, int pin_wake_btn) {