add dfu support

esphome/__main__.py

@@ -317,9 +317,18 @@ def upload_adafruit_nrfutil(config, port):
     from nordicsemi.dfu.dfu_transport_serial import DfuTransportSerial
     from nordicsemi.dfu.dfu_transport import DfuEvent
     from nordicsemi.dfu.dfu import Dfu
+    import serial
 
     idedata = platformio_api.get_idedata(config)
     dfu_package = str(Path(idedata.firmware_elf_path).with_suffix(".zip"))
+    ser = serial.Serial(port, 2400)
+    time.sleep(DfuTransportSerial.SERIAL_PORT_OPEN_WAIT_TIME)
+    ser.setDTR(True)
+    time.sleep(DfuTransportSerial.DTR_RESET_WAIT_TIME)
+    ser.close()
+
+    time.sleep(2)
+
     serial_backend = DfuTransportSerial(port)
     serial_backend.register_events_callback(DfuEvent.PROGRESS_EVENT, update_progress)
     dfu = Dfu(dfu_package, dfu_transport=serial_backend)

esphome/components/dfu/__init__.py

@@ -0,0 +1,24 @@
+import esphome.codegen as cg
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_ID,
+)
+
+dfu_ns = cg.esphome_ns.namespace("dfu")
+DeviceFirmwareUpdate = dfu_ns.class_("DeviceFirmwareUpdate", cg.Component)
+
+CONFIG_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.GenerateID(): cv.declare_id(DeviceFirmwareUpdate),
+        }
+    ).extend(cv.COMPONENT_SCHEMA),
+    cv.only_on_nrf52,
+)
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    # week symbol do not work for some reason so use wrap instaed
+    cg.add_build_flag("-Wl,--wrap=tud_cdc_line_state_cb")
+    await cg.register_component(var, config)

esphome/components/dfu/dfu.cpp

@@ -0,0 +1,49 @@
+#include "dfu.h"
+#include <Arduino.h>
+#include <Adafruit_TinyUSB.h>  // for Serial
+
+extern "C" {
+
+volatile bool goto_dfu = false;
+void __wrap_tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts) {
+  (void) rts;
+
+  // DTR = false is counted as disconnected
+  if (!dtr) {
+    // touch2400 only with first CDC instance (Serial)
+    if (itf == 0) {
+      cdc_line_coding_t coding;
+      tud_cdc_get_line_coding(&coding);
+
+      if (coding.bit_rate == 2400) {
+        goto_dfu = true;
+      }
+    }
+  }
+}
+}
+
+namespace esphome {
+namespace dfu {
+
+#define DFU_DBL_RESET_MEM 0x20007F7C
+#define DFU_DBL_RESET_MAGIC 0x5A1AD5  // SALADS
+uint32_t *dbl_reset_mem = ((uint32_t *) DFU_DBL_RESET_MEM);
+
+void DeviceFirmwareUpdate::loop() {
+  if (goto_dfu) {
+    goto_dfu = false;
+    (*dbl_reset_mem) = DFU_DBL_RESET_MAGIC;
+    pinMode(14, OUTPUT);
+    pinMode(16, OUTPUT);
+    digitalWrite(14, 1);
+    digitalWrite(16, 1);
+
+    delay(50);
+    digitalWrite(14, 0);
+    digitalWrite(16, 0);
+  }
+}
+
+}  // namespace dfu
+}  // namespace esphome

esphome/components/dfu/dfu.h

@@ -0,0 +1,10 @@
+#pragma once
+#include "esphome/core/component.h"
+
+namespace esphome {
+namespace dfu {
+class DeviceFirmwareUpdate : public Component {
+	void loop() override;
+};
+}
+}

esphome/config_validation.py

@@ -57,6 +57,7 @@ from esphome.const import (
     TYPE_GIT,
     TYPE_LOCAL,
     VALID_SUBSTITUTIONS_CHARACTERS,
+    PLATFORM_NRF52,
 )
 from esphome.core import (
     CORE,
@@ -595,6 +596,7 @@ def only_with_framework(frameworks):
 only_on_esp32 = only_on(PLATFORM_ESP32)
 only_on_esp8266 = only_on(PLATFORM_ESP8266)
 only_on_rp2040 = only_on(PLATFORM_RP2040)
+only_on_nrf52 = only_on(PLATFORM_NRF52)
 only_with_arduino = only_with_framework("arduino")
 only_with_esp_idf = only_with_framework("esp-idf")