ui: on-screen LED brightness menu (button-UI boards)

zephcore/adapters/board/ZephyrBoard.cpp

@@ -10,6 +10,7 @@
 #include <zephyr/sys/reboot.h>
 #include <zephyr/drivers/sensor.h>
 #include <zephyr/drivers/gpio.h>
+#include <zephyr/drivers/pwm.h>
 #include <stdio.h>
 #include <string.h>
 
@@ -97,19 +98,34 @@
 #endif
 #endif
 
-/* LoRa radio activity LED (optional — defined per-board via DT alias).  Still
- * called tx_led after "set leds.radio" gave it an RX mode, because the DT alias
- * it comes from is named lora-tx-led on every board that has one. */
-#if DT_NODE_EXISTS(DT_ALIAS(lora_tx_led))
+/* LoRa radio activity LED (optional — defined per-board via DT alias). Still
+ * called tx_led after "set leds.radio" gave it an RX mode, because the DT
+ * alias it comes from is named lora-tx-led on every board that has one.
+ *
+ * PWM path (DT_ALIAS(lora_tx_pwm_led)) takes priority when it exists — used
+ * on boards where the TX LED is the same physical LED as the heartbeat
+ * (e.g. T096, see helpers/ui/ui_common.c), so both share the one brightness
+ * in helpers/led_gate.h instead of the plain GPIO path fighting over the
+ * pin. */
+#if DT_NODE_EXISTS(DT_ALIAS(lora_tx_pwm_led))
+static const struct pwm_dt_spec tx_led_pwm = PWM_DT_SPEC_GET(DT_ALIAS(lora_tx_pwm_led));
+#define HAS_TX_LED_PWM 1
+#define HAS_TX_LED 0
+/* Init deferred to the combined tx_led_init() below (with the GPIO path),
+ * since both now also need to arm s_rx_pulse_off -- see that block. */
+#elif DT_NODE_EXISTS(DT_ALIAS(lora_tx_led))
 static const struct gpio_dt_spec tx_led =
 	GPIO_DT_SPEC_GET(DT_ALIAS(lora_tx_led), gpios);
+#define HAS_TX_LED_PWM 0
 #define HAS_TX_LED 1
 #else
+#define HAS_TX_LED_PWM 0
 #define HAS_TX_LED 0
 #endif
 
 /* True when this board wires the activity LED to the same pin as the heartbeat
- * (8 of the supported boards do).  Only those pay for the arbitration hold in
+ * (8 of the supported boards do, counting only the plain-GPIO ones -- see the
+ * PWM branch below for the rest).  Only those pay for the arbitration hold in
  * led_gate.c — everywhere else the two LEDs are independent and the calls
  * compile out.  led1 is checked as well because ui_common.c falls back to it
  * when a board has no led0. */
@@ -120,10 +136,36 @@ static const struct gpio_dt_spec tx_led =
       DT_NODE_EXISTS(DT_ALIAS(led1)) && \
       DT_SAME_NODE(DT_ALIAS(led1), DT_ALIAS(lora_tx_led))
 #define ZEPHCORE_LED_PIN_SHARED 1
+/* PWM equivalent: true when heartbeat and TX activity are aliased to the same
+ * PWM LED node (T096, Wireless Tracker V2). Not the case on every PWM board --
+ * RAK3401 has two independent PWM LEDs (green/blue), so this stays 0 there and
+ * the hold below is correctly never taken. */
+#elif HAS_TX_LED_PWM && DT_NODE_EXISTS(DT_ALIAS(heartbeat_pwm_led)) && \
+      DT_SAME_NODE(DT_ALIAS(heartbeat_pwm_led), DT_ALIAS(lora_tx_pwm_led))
+#define ZEPHCORE_LED_PIN_SHARED 1
 #else
 #define ZEPHCORE_LED_PIN_SHARED 0
 #endif
 
+/* PWM-or-GPIO write for the activity LED, mirroring heartbeat_led_write() in
+ * helpers/ui/ui_common.c -- same reasoning: the write itself must not care
+ * which path is compiled in, only the callers (onBeforeTransmit/
+ * onAfterTransmit/onPacketReceived/rx_pulse_off_handler below) do. */
+#if HAS_TX_LED_PWM
+static inline void tx_led_write(bool on)
+{
+	uint32_t pulse = on ? (uint32_t)((uint64_t)tx_led_pwm.period *
+					  zephcore_led_brightness_pct() / 100)
+			     : 0;
+	pwm_set_pulse_dt(&tx_led_pwm, pulse);
+}
+#elif HAS_TX_LED
+static inline void tx_led_write(bool on)
+{
+	gpio_pin_set_dt(&tx_led, on ? 1 : 0);
+}
+#endif
+
 #include <zephyr/logging/log.h>
 LOG_MODULE_REGISTER(zephcore_board, CONFIG_ZEPHCORE_BOARD_LOG_LEVEL);
 
@@ -173,8 +215,8 @@ static const struct device *const fuel_gauge_dev =
 #define HAS_FUEL_GAUGE 0
 #endif
 
-/* Initialize activity LED GPIO at boot */
-#if HAS_TX_LED
+/* Initialize activity LED (PWM or GPIO) at boot */
+#if HAS_TX_LED_PWM || HAS_TX_LED
 /* Width of the receive blink.  A transmit holds the LED for its whole airtime,
  * but a receive is a single edge — the packet is over by the time the driver
  * hands it up — so RX has to be a fixed one-shot.  30 ms is deliberately longer
@@ -187,7 +229,9 @@ static const struct device *const fuel_gauge_dev =
  * interlock that keeps an RX one-shot from clearing a pin that TX still owns:
  * the two are driven from different threads (radio TX path vs system work
  * queue), so without it a pulse landing mid-transmit would blank the LED for
- * the rest of the packet. */
+ * the rest of the packet. Applies equally to the PWM-shared boards (T096,
+ * Wireless Tracker V2): same race, same fix, just written through
+ * tx_led_write() instead of a bare gpio_pin_set_dt(). */
 static atomic_t s_tx_lit;
 static struct k_work_delayable s_rx_pulse_off;
 
@@ -199,17 +243,23 @@ static void rx_pulse_off_handler(struct k_work *work)
 	if (atomic_get(&s_tx_lit)) {
 		return;
 	}
-	gpio_pin_set_dt(&tx_led, 0);
+	tx_led_write(false);
 #if ZEPHCORE_LED_PIN_SHARED
 	zephcore_led_radio_hold_pin(false);
 #endif
 }
 
 static int tx_led_init(void)
 {
+#if HAS_TX_LED_PWM
+	if (device_is_ready(tx_led_pwm.dev)) {
+		pwm_set_pulse_dt(&tx_led_pwm, 0);  /* start dark, same as GPIO_OUTPUT_INACTIVE */
+	}
+#else
 	if (gpio_is_ready_dt(&tx_led)) {
 		gpio_pin_configure_dt(&tx_led, GPIO_OUTPUT_INACTIVE);
 	}
+#endif
 	k_work_init_delayable(&s_rx_pulse_off, rx_pulse_off_handler);
 	return 0;
 }
@@ -359,12 +409,14 @@ const char *ZephyrBoard::getManufacturerName() const
 
 void ZephyrBoard::onBeforeTransmit()
 {
-#if HAS_TX_LED
 	/* Honour the LED master gate ("set leds off") and then the activity mode
 	 * ("set leds.radio"). On a headless repeater this is the only LED that ever
 	 * lights, so both have to be checked here and not just in the UI layer.
 	 * onAfterTransmit() still clears the pin unconditionally, so a gate or mode
-	 * flipped mid-transmit can't strand it lit. */
+	 * flipped mid-transmit can't strand it lit. Same interlock on PWM-shared
+	 * boards (T096, Wireless Tracker V2) as on plain-GPIO ones -- only the
+	 * final write (tx_led_write()) differs. */
+#if HAS_TX_LED_PWM || HAS_TX_LED
 	uint8_t mode = zephcore_leds_radio_mode();
 	if (!zephcore_leds_disabled() &&
 	    (mode == LEDS_RADIO_TX || mode == LEDS_RADIO_ALL)) {
@@ -375,16 +427,16 @@ void ZephyrBoard::onBeforeTransmit()
 #if ZEPHCORE_LED_PIN_SHARED
 		zephcore_led_radio_hold_pin(true);
 #endif
-		gpio_pin_set_dt(&tx_led, 1);
+		tx_led_write(true);
 	}
 #endif
 }
 
 void ZephyrBoard::onAfterTransmit()
 {
-#if HAS_TX_LED
+#if HAS_TX_LED_PWM || HAS_TX_LED
 	atomic_set(&s_tx_lit, 0);
-	gpio_pin_set_dt(&tx_led, 0);
+	tx_led_write(false);
 #if ZEPHCORE_LED_PIN_SHARED
 	zephcore_led_radio_hold_pin(false);
 #endif
@@ -393,7 +445,7 @@ void ZephyrBoard::onAfterTransmit()
 
 void ZephyrBoard::onPacketReceived()
 {
-#if HAS_TX_LED
+#if HAS_TX_LED_PWM || HAS_TX_LED
 	uint8_t mode = zephcore_leds_radio_mode();
 	if (zephcore_leds_disabled() ||
 	    (mode != LEDS_RADIO_RX && mode != LEDS_RADIO_ALL)) {
@@ -409,7 +461,7 @@ void ZephyrBoard::onPacketReceived()
 #if ZEPHCORE_LED_PIN_SHARED
 	zephcore_led_radio_hold_pin(true);
 #endif
-	gpio_pin_set_dt(&tx_led, 1);
+	tx_led_write(true);
 	/* Reschedule rather than schedule: back-to-back packets should extend the
 	 * blink, not have the first one's handler cut the second one short. */
 	k_work_reschedule(&s_rx_pulse_off, K_MSEC(RX_PULSE_MS));

zephcore/adapters/datastore/ZephyrDataStore.cpp

@@ -907,6 +907,14 @@ void ZephyrDataStore::loadPrefs(NodePrefs &prefs)
 	if (off < len) {
 		prefs.leds_hb_mode = buf[off++];
 	}
+	/* Offset 174: led_brightness (ZephCore extension, since 1.17.4). Absent
+	 * in pre-existing files -> stays at the initNodePrefs() default of
+	 * ZEPHCORE_LED_DEFAULT_BRIGHTNESS_PCT (10%), same value a fresh node
+	 * already showed before this field was persisted. Range re-checked by
+	 * sanitizeNodePrefs() below. */
+	if (off < len) {
+		prefs.led_brightness = buf[off++];
+	}
 
 	sanitizeNodePrefs(&prefs);
 }
@@ -1022,7 +1030,9 @@ void ZephyrDataStore::savePrefs(const NodePrefs &prefs)
 	/* Offset 172-173: leds_radio_mode / leds_hb_mode (ZephCore extension). */
 	buf[off++] = prefs.leds_radio_mode;
 	buf[off++] = prefs.leds_hb_mode;
-	/* Total: 174 bytes */
+	/* Offset 174: led_brightness (ZephCore extension, since 1.17.4). */
+	buf[off++] = prefs.led_brightness;
+	/* Total: 175 bytes */
 
 	bool ok = atomicReplaceFile(PREFS_FILE, buf, off);
 	LOG_DBG("savePrefs: wrote %s, ok=%d (%d bytes), name='%.16s'",

zephcore/app/RepeaterDataStore.cpp

@@ -301,6 +301,11 @@ bool RepeaterDataStore::loadPrefs(NodePrefs& prefs) {
      * (activity LED on transmit, heartbeat with unread indication). */
     fs_read(&file, &prefs.leds_radio_mode, sizeof(prefs.leds_radio_mode));
     fs_read(&file, &prefs.leds_hb_mode, sizeof(prefs.leds_hb_mode));
+    /* LED brightness, offset 311 (ZephCore extension, since 1.17.4). Absent
+     * in <312-byte files; leaves the initNodePrefs() default of
+     * ZEPHCORE_LED_DEFAULT_BRIGHTNESS_PCT (10%), same value a fresh node
+     * already showed before this field was persisted. */
+    fs_read(&file, &prefs.led_brightness, sizeof(prefs.led_brightness));
 
     fs_close(&file);
 
@@ -467,6 +472,8 @@ bool RepeaterDataStore::savePrefs(const NodePrefs& prefs) {
     /* LED activity/heartbeat modes (offsets 309-310) */
     fs_write(&file, &prefs.leds_radio_mode, sizeof(prefs.leds_radio_mode));
     fs_write(&file, &prefs.leds_hb_mode, sizeof(prefs.leds_hb_mode));
+    /* LED brightness (offset 311, since 1.17.4) */
+    fs_write(&file, &prefs.led_brightness, sizeof(prefs.led_brightness));
 
     ret = fs_sync(&file);
     fs_close(&file);

zephcore/app/main_observer.cpp

@@ -385,6 +385,7 @@ int main(void)
 		zephcore_leds_set_disabled(leds_off);
 		zephcore_leds_set_radio_mode(prefs->leds_radio_mode);
 		zephcore_leds_set_hb_mode(prefs->leds_hb_mode);
+		zephcore_led_set_brightness_pct(prefs->led_brightness);
 		LOG_INF("LEDs: %s (from prefs)", leds_off ? "disabled" : "enabled");
 	}
 

zephcore/boards/common/esp32s3_pwm_led.conf

@@ -0,0 +1,15 @@
+# Enable PWM on ESP32-S3 sysbuild targets (shared heartbeat/TX LED brightness,
+# see the heartbeat-pwm-led / lora-tx-pwm-led devicetree aliases consumed by
+# helpers/ui/ui_common.c and adapters/board/ZephyrBoard.cpp).
+#
+# Deliberately NOT in the board *_defconfig: that file is shared by every
+# sysbuild image for the board, including mcuboot, whose minimal kernel
+# config has no k_sem_give()/k_sem_take() -- CONFIG_PWM=y there links fine for
+# the app image but fails mcuboot's link with "undefined reference to
+# z_impl_k_sem_give/take" (drivers/pwm/pwm_led_esp32.c uses a semaphore).
+# EXTRA_CONF_FILE scopes this to the app ("zephcore") image only.
+#
+# Build with:
+#   -DEXTRA_CONF_FILE="boards/common/esp32s3_usb.conf;boards/common/esp32s3_pwm_led.conf"
+
+CONFIG_PWM=y

zephcore/boards/esp32/heltec_wifi_lora32_v43/heltec_wifi_lora32_v43_procpu.dts

@@ -47,6 +47,13 @@
 		led0 = &led0;
 		pwm-0 = &ledc0;
 		pwm-led0 = &pwm_led_white;
+		/* Single physical LED, shared between the heartbeat and LoRa TX
+		 * activity roles (same node aliased twice), same pattern as T096 and
+		 * Wireless Tracker V2 -- see helpers/ui/ui_common.c and
+		 * adapters/board/ZephyrBoard.cpp (ZEPHCORE_LED_PIN_SHARED covers the
+		 * arbitration between the two roles automatically). */
+		heartbeat-pwm-led = &pwm_led_white;
+		lora-tx-pwm-led = &pwm_led_white;
 		uart-0 = &uart0;
 		i2c-0 = &i2c0;
 		lora0 = &lora0;

zephcore/boards/esp32/heltec_wireless_tracker_v2/heltec_wireless_tracker_v2-pinctrl.dtsi

@@ -72,4 +72,11 @@
 			output-low;
 		};
 	};
+
+	ledc0_default: ledc0_default {
+		group1 {
+			pinmux = <LEDC_CH0_GPIO18>;
+			output-enable;
+		};
+	};
 };

zephcore/boards/esp32/heltec_wireless_tracker_v2/heltec_wireless_tracker_v2_procpu.dts

@@ -30,6 +30,7 @@
 #include <zephyr/dt-bindings/input/input-event-codes.h>
 #include <zephyr/dt-bindings/lora/sx126x.h>
 #include <zephyr/dt-bindings/gpio/espressif-esp32-gpio.h>
+#include <zephyr/dt-bindings/pwm/pwm.h>
 #include "heltec_wireless_tracker_v2-pinctrl.dtsi"
 
 / {
@@ -39,6 +40,8 @@
 	aliases {
 		led0 = &status_led;
 		lora-tx-led = &status_led;
+		heartbeat-pwm-led = &pwm_status_led;
+		lora-tx-pwm-led = &pwm_status_led;
 		uart-0 = &uart0;
 		uart-2 = &uart2;
 		i2c-0 = &i2c0;
@@ -69,6 +72,22 @@
 		};
 	};
 
+	/* Same GPIO18 net as status_led above, driven through the LEDC PWM
+	 * peripheral instead of a raw GPIO write. Single LED doubling as
+	 * heartbeat, message/shutdown flash and LoRa TX indicator (same
+	 * "Option 1" shared-brightness pattern as T096, see helpers/ui/ui_common.c
+	 * and adapters/board/ZephyrBoard.cpp: heartbeat-pwm-led/lora-tx-pwm-led
+	 * aliases give every one of those events a single 0-100 brightness knob,
+	 * RAM-only, on top of the existing persisted on/off gate. */
+	pwm_leds {
+		compatible = "pwm-leds";
+
+		pwm_status_led: pwm_led_gpio18 {
+			label = "Status PWM LED";
+			pwms = <&ledc0 0 PWM_MSEC(10) PWM_POLARITY_NORMAL>;
+		};
+	};
+
 	buttons: buttons {
 		compatible = "gpio-keys";
 
@@ -231,6 +250,19 @@
 	status = "okay";
 };
 
+&ledc0 {
+	pinctrl-0 = <&ledc0_default>;
+	pinctrl-names = "default";
+	status = "okay";
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	channel0@0 {
+		reg = <0x0>;
+		timer = <0>;
+	};
+};
+
 &i2c0 {
 	status = "okay";
 	clock-frequency = <I2C_BITRATE_FAST>;

zephcore/boards/nrf52840/heltec_t096/heltec_t096_nrf52840-pinctrl.dtsi

@@ -80,4 +80,20 @@
 			low-power-enable;
 		};
 	};
+
+	/* Heartbeat/TX LED, PWM path (see heltec_t096_nrf52840.dts, pwm_led_white).
+	 * Same P0.28 net as the plain gpio-leds node — free in pinctrl, no
+	 * other peripheral claims it. */
+	pwm0_default: pwm0_default {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT0, 0, 28)>;
+		};
+	};
+
+	pwm0_sleep: pwm0_sleep {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT0, 0, 28)>;
+			low-power-enable;
+		};
+	};
 };