[improv_serial] Add uart bus support and host integration test (#18794)

esphome/components/host/__init__.py

@@ -50,6 +50,7 @@ async def to_code(config: ConfigType) -> None:
     cg.add_define("USE_ESPHOME_HOST_MAC_ADDRESS", config[CONF_MAC_ADDRESS].parts)
     cg.add_build_flag("-std=gnu++20")
     cg.add_define("ESPHOME_BOARD", "host")
+    cg.add_define("ESPHOME_VARIANT", "HOST")
     cg.add_define(ThreadModel.MULTI_ATOMICS)
     cg.add_platformio_option("platform", "platformio/native")
     cg.add_platformio_option("lib_ldf_mode", "off")

esphome/components/improv_serial/__init__.py

@@ -1,9 +1,15 @@
 import esphome.codegen as cg
-from esphome.components import improv_base
+from esphome.components import improv_base, uart
 from esphome.components.esp32 import VARIANT_ESP32S3, get_esp32_variant
 from esphome.components.logger import USB_CDC
 import esphome.config_validation as cv
-from esphome.const import CONF_BAUD_RATE, CONF_HARDWARE_UART, CONF_ID, CONF_LOGGER
+from esphome.const import (
+    CONF_BAUD_RATE,
+    CONF_HARDWARE_UART,
+    CONF_ID,
+    CONF_LOGGER,
+    CONF_UART_ID,
+)
 from esphome.core import CORE
 import esphome.final_validate as fv
 from esphome.types import ConfigType
@@ -17,13 +23,35 @@ improv_serial_ns = cg.esphome_ns.namespace("improv_serial")
 ImprovSerialComponent = improv_serial_ns.class_("ImprovSerialComponent", cg.Component)
 
 CONFIG_SCHEMA = (
-    cv.Schema({cv.GenerateID(): cv.declare_id(ImprovSerialComponent)})
+    cv.Schema(
+        {
+            cv.GenerateID(): cv.declare_id(ImprovSerialComponent),
+            # YAML only: rewiring Improv onto another UART is not a knob for a
+            # visual editor and the device builder must not expose it
+            cv.Optional(CONF_UART_ID, visibility=cv.Visibility.YAML_ONLY): cv.use_id(
+                uart.UARTComponent
+            ),
+        }
+    )
     .extend(improv_base.IMPROV_SCHEMA)
     .extend(cv.COMPONENT_SCHEMA)
 )
 
 
-def validate_logger(config: ConfigType) -> None:
+_UART_FINAL_VALIDATE = uart.final_validate_device_schema(
+    "improv_serial", require_tx=True, require_rx=True
+)
+
+
+def validate_transport(config: ConfigType) -> None:
+    if CONF_UART_ID in config:
+        # A dedicated UART bus is used; the logger's serial settings are irrelevant,
+        # but the bus itself must be bidirectional and not claimed by another device
+        _UART_FINAL_VALIDATE(config)
+        return
+    # The host logger has no serial port for Improv to share
+    if CORE.is_host:
+        raise cv.Invalid("improv_serial on the host platform requires uart_id")
     logger_conf = fv.full_config.get()[CONF_LOGGER]
     if logger_conf[CONF_BAUD_RATE] == 0:
         raise cv.Invalid("improv_serial requires the logger baud_rate to be not 0")
@@ -36,7 +64,7 @@ def validate_logger(config: ConfigType) -> None:
         )
 
 
-FINAL_VALIDATE_SCHEMA = validate_logger
+FINAL_VALIDATE_SCHEMA = validate_transport
 
 
 async def to_code(config: ConfigType) -> None:
@@ -44,3 +72,6 @@ async def to_code(config: ConfigType) -> None:
     await cg.register_component(var, config)
     await improv_base.setup_improv_core(var, config, "improv_serial")
     cg.add_define("USE_IMPROV_SERIAL")
+    if (uart_id := config.get(CONF_UART_ID)) is not None:
+        cg.add(var.set_uart(await cg.get_variable(uart_id)))
+        cg.add_define("USE_IMPROV_SERIAL_UART")

esphome/components/improv_serial/improv_serial_component.cpp

@@ -15,7 +15,9 @@ static const char *const TAG = "improv_serial";
 
 void ImprovSerialComponent::setup() {
   global_improv_serial_component = this;
-#ifdef USE_ESP32
+#ifdef USE_IMPROV_SERIAL_UART
+  // Transport is a dedicated UART bus set via set_uart() in generated code
+#elif defined(USE_ESP32)
   this->uart_num_ = logger::global_logger->get_uart_num();
   this->uart_selection_ = logger::global_logger->get_uart();
 #elif defined(USE_ARDUINO)
@@ -89,7 +91,13 @@ void ImprovSerialComponent::write_data_(const uint8_t *data, const size_t size)
   }
   this->tx_header_[TX_CHECKSUM_IDX] = checksum;
 
-#ifdef USE_ESP32
+#ifdef USE_IMPROV_SERIAL_UART
+  this->uart_->write_array(this->tx_header_, header_tx_len);
+  if (there_is_data) {
+    this->uart_->write_array(data, size);
+    this->uart_->write_array(&this->tx_header_[TX_CHECKSUM_IDX], 2);  // Footer: checksum and newline
+  }
+#elif defined(USE_ESP32)
   switch (this->uart_selection_) {
     case logger::UART_SELECTION_UART0:
     case logger::UART_SELECTION_UART1:

esphome/components/improv_serial/improv_serial_component.h

@@ -10,7 +10,9 @@
 #include <improv.h>
 #include <vector>
 
-#ifdef USE_ESP32
+#ifdef USE_IMPROV_SERIAL_UART
+#include "esphome/components/uart/uart_component.h"
+#elif defined(USE_ESP32)
 #include <driver/uart.h>
 #ifdef USE_LOGGER_USB_SERIAL_JTAG
 #include <driver/usb_serial_jtag.h>
@@ -53,6 +55,10 @@ class ImprovSerialComponent final : public Component, public improv_base::Improv
 
   float get_setup_priority() const override { return setup_priority::AFTER_WIFI; }
 
+#ifdef USE_IMPROV_SERIAL_UART
+  void set_uart(uart::UARTComponent *uart) { this->uart_ = uart; }
+#endif
+
  protected:
   bool parse_improv_serial_byte_(uint8_t byte);
   bool parse_improv_payload_(improv::ImprovCommand &command);
@@ -69,7 +75,11 @@ class ImprovSerialComponent final : public Component, public improv_base::Improv
   ESPHOME_ALWAYS_INLINE optional<uint8_t> read_byte_() {
     optional<uint8_t> byte;
     uint8_t data = 0;
-#ifdef USE_ESP32
+#ifdef USE_IMPROV_SERIAL_UART
+    if (this->uart_->available() && this->uart_->read_byte(&data)) {
+      byte = data;
+    }
+#elif defined(USE_ESP32)
     switch (this->uart_selection_) {
       case logger::UART_SELECTION_UART0:
       case logger::UART_SELECTION_UART1:
@@ -129,7 +139,9 @@ class ImprovSerialComponent final : public Component, public improv_base::Improv
       '\n',
   };
 
-#ifdef USE_ESP32
+#ifdef USE_IMPROV_SERIAL_UART
+  uart::UARTComponent *uart_{nullptr};
+#elif defined(USE_ESP32)
   uart_port_t uart_num_;
   logger::UARTSelection uart_selection_{logger::UART_SELECTION_UART0};
 #elif defined(USE_ARDUINO)

esphome/core/defines.h

@@ -537,6 +537,8 @@
 
 #ifdef USE_HOST
 #define USE_HTTP_REQUEST_RESPONSE
+// Host only: the uart arm would shadow the native logger UART arms in other envs
+#define USE_IMPROV_SERIAL_UART
 #define USE_SOCKET_IMPL_BSD_SOCKETS
 #define USE_ESPHOME_TASK_LOG_BUFFER
 #define ESPHOME_TASK_LOG_BUFFER_SIZE 64