feat(ui-lvgl): tap-to-wake switch, the side button no longer wakes

Settings > Display & power > WAKE > Tap to wake (NVS, on by default):
off, only the top WAKE button turns the screen on. The side USER button
doesn't wake the screen any more (a press in a pocket); held, it still
mutes / unmutes with the screen off. Roadmap: buttons corrected (WAKE is
the top one), USER to open the main menu page later.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/development/l2-roadmap.md

@@ -5,8 +5,10 @@ for what comes next, in order. Tick items off as they land.
 
 Decisions already made:
 
-- **Buttons:** WAKE (side, expander P00) turns the screen off / on. USER/BOOT
-  goes back; holding it mutes / unmutes the device.
+- **Buttons:** WAKE (top, expander P00) turns the screen off / on. USER/BOOT
+  (side) goes back; holding it mutes / unmutes the device, also with the
+  screen off; it doesn't wake the screen (a press in a pocket). Later: a
+  click takes you to the main menu page, once the menu is rebuilt.
 - **Placeholders:** the "+" popup next to a text field is the placeholder UI;
   it must offer every placeholder and appear at every field that sends text.
 - **Message history:** kept on the SD card, about 100 per conversation to
@@ -251,7 +253,8 @@ User list, second batch (2026-09-26):
       the MeshCore title font (the wordmark's letters plus l, v, d, digits,
       '.', '-' drawn to match; Noto for a line with anything else).
 - [ ] Emoji, ideally the full range (glyphs could live on the SD card).
-- [ ] Tap-to-wake toggle.
+- [x] Tap-to-wake toggle (Settings > Display & power > WAKE, NVS, on by
+      default; off: only the top button wakes it).
 - [ ] Favourites as their own screen in the menu rather than a tile.
 - [ ] WiFi indicator icon in the status bar.
 

examples/companion_radio/ui-lvgl/LvglPort.h

@@ -226,6 +226,21 @@ static void saveLiveCap(int idx) {
   p.putChar("ltcap", (int8_t)idx);
   p.end();
 }
+// Settings > Display & power > Tap to wake: a touch turns the dark screen on
+// (off: only the side button does).
+static bool loadTapWake() {
+  Preferences p;
+  if (!p.begin("mc_ui", true)) return true;
+  bool on = p.getBool("tapwake", true);
+  p.end();
+  return on;
+}
+static void saveTapWake(bool on) {
+  Preferences p;
+  if (!p.begin("mc_ui", false)) return;
+  p.putBool("tapwake", on);
+  p.end();
+}
 // Filesystem size and space in use (Settings > Storage), plus the card's own
 // size -- a card whose FAT partition is small (e.g. written by a Raspberry Pi
 // imager) shows both. The first free-space count on a big card takes a moment.
@@ -514,6 +529,9 @@ static void saveHistKeep(int idx) { s_hist_keep = idx; }
 static int s_live_cap = -1;
 static int loadLiveCap() { return s_live_cap; }
 static void saveLiveCap(int idx) { s_live_cap = idx; }
+static bool s_tap_wake = true;
+static bool loadTapWake() { return s_tap_wake; }
+static void saveTapWake(bool on) { s_tap_wake = on; }
 // The browser has no card: a nominal 32 GB, used = what the files add up to
 // (the storage screen counts them anyway; it passes that in).
 static bool sdInfo(uint64_t& total, uint64_t& used, uint64_t& card) { total = card = 32ULL << 30; used = 0; return true; }

examples/companion_radio/ui-lvgl/UITask.cpp

@@ -222,6 +222,7 @@ void UITask::begin(DisplayDriver* display_drv, SensorManager* sensors, NodePrefs
     s_archive.restore(_core->history);
     _core->history.setArchive(&s_archive);
   }
+  _tap_wake = lvport::loadTapWake();
   msgtext::seedQuick(node_prefs);   // "OK" in quick message 1 on first boot
   _nearby = new NearbyModel();
   _nearby->bindModel(_core, node_prefs);
@@ -274,8 +275,9 @@ void UITask::loop() {
   pollConnection();
   drainCoreEvents();
 
-  // USER (BOOT) button: back; held, mutes / unmutes. WAKE button: screen off /
-  // on. Either one silences a ringing alarm first.
+  // USER (BOOT, side) button: back; held, mutes / unmutes, also with the
+  // screen off, which it doesn't wake. WAKE (top) button: screen off / on.
+  // Either one silences a ringing alarm first.
   bool btn_click = false, btn_hold = false, wake_press = false;
 #ifdef PIN_USER_BTN
   int ev = user_btn.check();
@@ -298,10 +300,10 @@ void UITask::loop() {
   if ((btn_click || btn_hold || wake_press) && _core->clock.isRinging()) dismissRing();
   else if (wake_press) { if (_asleep) wake(); else sleep(); }
   else if (btn_hold) toggleMute();
-  else if (btn_click) { if (_asleep) wake(); else if (!locked()) back(); }
+  else if (btn_click) { if (!_asleep && !locked()) back(); }   // the side button doesn't wake: pockets
 
   if (_asleep) {
-    if (lvport::touched()) { lvport::swallowTouch(); wake(); }
+    if (lvport::touched()) { lvport::swallowTouch(); if (_tap_wake) wake(); }   // off: the top (WAKE) button only
   } else {
     uint32_t aoff = autoOffMillis();
     if (aoff > 0 && lv_display_get_inactive_time(NULL) > aoff && !_core->clock.isRinging() && !otaBusy()) sleep();
@@ -2374,6 +2376,15 @@ void UITask::setBrightnessPct(uint8_t pct, bool save) {
   if (save) the_mesh.savePrefs();
 }
 
+static void onTapWake(lv_event_t* e) {
+  s_ui->setTapWake(lv_obj_has_state((lv_obj_t*)lv_event_get_target(e), LV_STATE_CHECKED));
+}
+
+void UITask::setTapWake(bool on) {
+  _tap_wake = on;
+  lvport::saveTapWake(on);
+}
+
 void UITask::buildSchemaSettings() {
   lv_obj_t* body = newScreen(settings::pageTitle(_settings_page), true);
   _prune_lbl = nullptr;
@@ -2390,6 +2401,10 @@ void UITask::buildSchemaSettings() {
     lv_obj_center(_prune_lbl);
   }
   if (_settings_page == settings::PG_DEVICE) {   // after Lock screen's section, in NVS not the schema
+    sectionTitle(body, "WAKE");
+    lv_obj_t* tw = switchRow(body, "Tap to wake", "Off: only the top button turns it on", nullptr);
+    if (_tap_wake) lv_obj_add_state(tw, LV_STATE_CHECKED);
+    lv_obj_add_event_cb(tw, onTapWake, LV_EVENT_VALUE_CHANGED, NULL);
     sectionTitle(body, "SECURITY");
     listRow(body, LV_SYMBOL_EYE_CLOSE "  Screen PIN", _pin[0] ? "On  -  asked when the screen wakes" : "Off",
             onPinSetup, NULL);

examples/companion_radio/ui-lvgl/UITask.h

@@ -64,6 +64,7 @@ public:
   void mapPan(int dx, int dy);
   void mapOpenMarker(int idx);
   void mapDownloadPopup();
+  void setTapWake(bool on);
   void mapDownloadClose();
   void mapDownloadStart();
   void mapDownloadStop();
@@ -404,6 +405,7 @@ private:
   lv_obj_t* _prune_lbl = nullptr;
   // Screen PIN (DeviceScreen.h); stored in NVS (lvport::loadPin)
   char      _pin[9] = "";          // "" = no PIN
+  bool      _tap_wake = true;      // a touch wakes the dark screen (NVS)
   char      _pin_entry[9] = "";    // digits typed so far
   char      _pin_new[9] = "";      // setup: the first entry, waiting for its confirmation
   uint8_t   _pin_fails = 0;