[ds248x] Add OneWireBus platform for DS248x I2C-to-1Wire bridges (#12717)

CODEOWNERS

@@ -145,6 +145,7 @@ esphome/components/dlms_meter/* @latonita @PolarGoose @SimonFischer04 @Tomer27cz
 esphome/components/dps310/* @kbx81
 esphome/components/ds1307/* @badbadc0ffee
 esphome/components/ds2484/* @mrk-its
+esphome/components/ds248x/* @tomwellnitz
 esphome/components/dsmr/* @glmnet @PolarGoose
 esphome/components/duty_time/* @dudanov
 esphome/components/ee895/* @Stock-M

esphome/components/ds248x/__init__.py

@@ -0,0 +1,112 @@
+from esphome import pins
+import esphome.codegen as cg
+from esphome.components import i2c
+import esphome.config_validation as cv
+from esphome.const import CONF_ID, CONF_SLEEP_PIN, CONF_TYPE
+
+CODEOWNERS = ["@tomwellnitz"]
+MULTI_CONF = True
+DEPENDENCIES = ["i2c"]
+
+CONF_DS248X_ID = "ds248x_id"
+CONF_BUS_SLEEP = "bus_sleep"
+CONF_HUB_SLEEP = "hub_sleep"
+CONF_ACTIVE_PULLUP = "active_pullup"
+
+CONF_RESET_LOW_TIME = "reset_low_time"
+CONF_MASTER_SAMPLE_TIME = "master_sample_time"
+CONF_WRITE_0_LOW_TIME = "write_0_low_time"
+CONF_RECOVERY_TIME = "recovery_time"
+CONF_ACTIVE_PULLUP_RESISTANCE = "active_pullup_resistance"
+
+TYPE_DS2482_100 = "ds2482-100"
+TYPE_DS2482_101 = "ds2482-101"
+TYPE_DS2482_800 = "ds2482-800"
+TYPE_DS2484 = "ds2484"
+
+CHANNEL_COUNTS = {
+    TYPE_DS2482_100: 1,
+    TYPE_DS2482_101: 1,
+    TYPE_DS2482_800: 8,
+    TYPE_DS2484: 1,
+}
+
+ds248x_ns = cg.esphome_ns.namespace("ds248x")
+DS248xComponent = ds248x_ns.class_("DS248xComponent", cg.Component, i2c.I2CDevice)
+
+
+def _component_schema(*extras):
+    schema = cv.Schema(
+        {
+            cv.GenerateID(): cv.declare_id(DS248xComponent),
+            cv.Optional(CONF_ACTIVE_PULLUP, default=False): cv.boolean,
+        }
+    )
+    for extra in extras:
+        schema = schema.extend(extra)
+    return schema.extend(cv.COMPONENT_SCHEMA).extend(i2c.i2c_device_schema(0x18))
+
+
+SLEEP_SCHEMA = {
+    cv.Optional(CONF_SLEEP_PIN): pins.internal_gpio_output_pin_schema,
+    cv.Optional(CONF_BUS_SLEEP, default=False): cv.boolean,
+    cv.Optional(CONF_HUB_SLEEP, default=False): cv.boolean,
+}
+
+DS2484_SCHEMA = {
+    cv.Optional(CONF_RESET_LOW_TIME): cv.int_range(min=0, max=15),
+    cv.Optional(CONF_MASTER_SAMPLE_TIME): cv.int_range(min=0, max=15),
+    cv.Optional(CONF_WRITE_0_LOW_TIME): cv.int_range(min=0, max=15),
+    cv.Optional(CONF_RECOVERY_TIME): cv.int_range(min=0, max=15),
+    cv.Optional(CONF_ACTIVE_PULLUP_RESISTANCE): cv.enum(
+        {
+            # DS2484 Table 7: value codes 0-5 map to 500 ohm, 6-15 map to 1000 ohm.
+            "500ohm": 0,
+            "1000ohm": 6,
+        }
+    ),
+}
+
+CONFIG_SCHEMA = cv.typed_schema(
+    {
+        TYPE_DS2482_100: _component_schema(),
+        TYPE_DS2482_101: _component_schema(SLEEP_SCHEMA),
+        TYPE_DS2482_800: _component_schema(),
+        TYPE_DS2484: _component_schema(SLEEP_SCHEMA, DS2484_SCHEMA),
+    },
+    key=CONF_TYPE,
+    lower=True,
+)
+
+
+def get_channel_count(config):
+    return CHANNEL_COUNTS[config[CONF_TYPE]]
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    await cg.register_component(var, config)
+    await i2c.register_i2c_device(var, config)
+
+    cg.add(var.set_active_pullup(config[CONF_ACTIVE_PULLUP]))
+    cg.add(var.set_channel_count(get_channel_count(config)))
+
+    if CONF_BUS_SLEEP in config:
+        cg.add(var.set_bus_sleep(config[CONF_BUS_SLEEP]))
+    if CONF_HUB_SLEEP in config:
+        cg.add(var.set_hub_sleep(config[CONF_HUB_SLEEP]))
+
+    if CONF_RESET_LOW_TIME in config:
+        cg.add(var.set_val_trstl(config[CONF_RESET_LOW_TIME]))
+    if CONF_MASTER_SAMPLE_TIME in config:
+        cg.add(var.set_val_tmsp(config[CONF_MASTER_SAMPLE_TIME]))
+    if CONF_WRITE_0_LOW_TIME in config:
+        cg.add(var.set_val_tw0l(config[CONF_WRITE_0_LOW_TIME]))
+    if CONF_RECOVERY_TIME in config:
+        cg.add(var.set_val_trec0(config[CONF_RECOVERY_TIME]))
+    if CONF_ACTIVE_PULLUP_RESISTANCE in config:
+        cg.add(var.set_val_rwpu(config[CONF_ACTIVE_PULLUP_RESISTANCE]))
+
+    if CONF_SLEEP_PIN in config:
+        pin = await cg.gpio_pin_expression(config[CONF_SLEEP_PIN])
+        cg.add(var.set_sleep_pin(pin))

esphome/components/ds248x/ds248x.cpp

@@ -0,0 +1,320 @@
+#include "ds248x.h"
+#include "esphome/core/log.h"
+#include "esphome/core/helpers.h"
+
+namespace esphome::ds248x {
+
+static const char *const TAG = "ds248x";
+
+void DS248xComponent::setup() {
+  ESP_LOGCONFIG(TAG, "Setting up DS248x...");
+
+  // Wake up device if sleep pin is configured
+  if (this->sleep_pin_) {
+    this->sleep_pin_->setup();
+    this->sleep_pin_->pin_mode(esphome::gpio::FLAG_OUTPUT);
+    this->sleep_pin_->digital_write(true);  // Wake up
+    delay(1);                               // DS2482-101 Datasheet: tOSCWUP = 100μs (using 10x margin)
+  }
+
+  // Probe device
+  ESP_LOGD(TAG, "Probing DS248x...");
+  uint8_t status = 0;
+  if (this->read(&status, 1) == i2c::ERROR_OK) {
+    ESP_LOGD(TAG, "Device responded! Status: 0x%02x", status);
+  } else {
+    ESP_LOGW(TAG, "Device did not respond. Trying reset anyway...");
+  }
+
+  if (!this->device_reset_()) {
+    ESP_LOGW(TAG, "DS248x reset failed during setup!");
+  }
+
+  // Configure device
+  if (!this->device_configure_()) {
+    ESP_LOGE(TAG, "DS248x configuration failed!");
+    this->mark_failed();
+    return;
+  }
+
+  // Reset to Channel 0
+  this->select_channel(0);
+
+  ESP_LOGI(TAG, "DS248x initialized successfully.");
+}
+
+void DS248xComponent::on_shutdown() {
+  if (this->sleep_pin_ && (this->hub_sleep_ || this->bus_sleep_)) {
+    this->sleep_pin_->digital_write(false);  // Sleep
+  }
+}
+
+void DS248xComponent::dump_config() {
+  ESP_LOGCONFIG(TAG, "DS248x:");
+  LOG_I2C_DEVICE(this);
+  ESP_LOGCONFIG(TAG, "  Channel Count: %d", this->channel_count_);
+  ESP_LOGCONFIG(TAG, "  Active Pullup: %s", YESNO(this->active_pullup_));
+  if (this->ds2484_mode_) {
+    ESP_LOGCONFIG(TAG, "  DS2484 Mode: enabled");
+  }
+}
+
+// --- Internal Helpers ---
+
+// Datasheet command durations are sub-2ms; allow a little margin before forcing recovery.
+static constexpr uint32_t BUSY_TIMEOUT_MS = 5;
+
+bool DS248xComponent::set_read_pointer_(uint8_t ptr) { return this->write_byte(DS248X_COMMAND_SETREADPTR, ptr); }
+
+bool DS248xComponent::wait_busy_() {
+  uint32_t start = millis();
+  do {
+    uint8_t status;
+    if (this->read(&status, 1) == i2c::ERROR_OK && !(status & DS248X_STATUS_BUSY))
+      return true;
+    delayMicroseconds(100);
+  } while (millis() - start < BUSY_TIMEOUT_MS);
+  ESP_LOGW(TAG, "DS248x busy timeout");
+  bool recovered = this->device_reset_() && this->device_configure_();
+  this->current_channel_ = -1;
+  if (!recovered) {
+    ESP_LOGE(TAG, "DS248x recovery failed after busy timeout");
+    this->mark_failed();
+  }
+  return false;
+}
+
+bool DS248xComponent::device_reset_() {
+  ESP_LOGD(TAG, "Resetting device...");
+  uint8_t cmd = DS248X_COMMAND_RESET;
+  if (this->write(&cmd, 1) != i2c::ERROR_OK)
+    return false;
+
+  uint8_t status;
+  if (this->read(&status, 1) != i2c::ERROR_OK)
+    return false;
+
+  if (!(status & DS248X_STATUS_RST)) {
+    ESP_LOGW(TAG, "Device reset failed (RST bit not set)");
+    return false;
+  }
+
+  this->current_channel_ = -1;
+  return true;
+}
+
+bool DS248xComponent::device_configure_() {
+  ESP_LOGD(TAG, "Configuring device...");
+
+  if (!this->write_config_()) {
+    ESP_LOGW(TAG, "Config write/verify failed");
+    return false;
+  }
+
+  ESP_LOGD(TAG, "Configured successfully");
+
+  // DS2484 Configuration
+  if (this->ds2484_mode_) {
+    if (this->ds2484_trstl_ != DS2484_PARAM_UNSET &&
+        !this->configure_ds2484_port_(DS2484_PORT_PARAM_TRSTL, this->ds2484_trstl_))
+      return false;
+    if (this->ds2484_tmsp_ != DS2484_PARAM_UNSET &&
+        !this->configure_ds2484_port_(DS2484_PORT_PARAM_TMSP, this->ds2484_tmsp_))
+      return false;
+    if (this->ds2484_tw0l_ != DS2484_PARAM_UNSET &&
+        !this->configure_ds2484_port_(DS2484_PORT_PARAM_TW0L, this->ds2484_tw0l_))
+      return false;
+    if (this->ds2484_trec0_ != DS2484_PARAM_UNSET &&
+        !this->configure_ds2484_port_(DS2484_PORT_PARAM_TREC0, this->ds2484_trec0_))
+      return false;
+    if (this->ds2484_rwpu_ != DS2484_PARAM_UNSET &&
+        !this->configure_ds2484_port_(DS2484_PORT_PARAM_RWPU, this->ds2484_rwpu_))
+      return false;
+  }
+
+  return true;
+}
+
+bool DS248xComponent::configure_ds2484_port_(uint8_t param, uint8_t val) {
+  uint8_t cmd = DS2484_COMMAND_ADJUSTPORT;
+  // Control Byte format (DS2484 Table 6): P[2:0] in bits 7:5, OD in bit 4, VAL[3:0] in bits 3:0
+  uint8_t data = ((param & 0x07) << 5) | (val & 0x0F);
+
+  // The DS2484 always acknowledges the Adjust 1-Wire Port control byte (datasheet "Adjust
+  // 1-Wire Port"), so a successful write confirms the update. We deliberately do not read
+  // back to verify: a single read of the Port Configuration register always returns the
+  // fixed 8-byte report starting at Byte 1 (tRSTL standard speed), not the parameter that
+  // was just written, so a per-parameter readback comparison would spuriously fail for
+  // tMSP/tW0L/tREC0/RWPU.
+  if (!this->write_byte(cmd, data)) {
+    ESP_LOGW(TAG, "DS2484 port config failed (param %d)", param);
+    return false;
+  }
+
+  return this->set_read_pointer_(DS248X_POINTER_STATUS);
+}
+
+bool DS248xComponent::write_config_() {
+  uint8_t config = 0;
+  if (this->active_pullup_)
+    config |= DS248X_CONFIG_ACTIVE_PULLUP;
+
+  // The DS248x only accepts the config byte if the upper nibble is the one's-complement of the lower nibble.
+  uint8_t config_byte = (config & 0x0F) | ((~config & 0x0F) << 4);
+
+  if (!this->write_byte(DS248X_COMMAND_WRITECONFIG, config_byte)) {
+    ESP_LOGW(TAG, "Failed to write config byte");
+    return false;
+  }
+
+  if (!this->set_read_pointer_(DS248X_POINTER_CONFIG)) {
+    return false;
+  }
+
+  uint8_t read_config;
+  if (this->read(&read_config, 1) != i2c::ERROR_OK) {
+    ESP_LOGW(TAG, "Failed to read back config byte");
+    return false;
+  }
+
+  if ((read_config & 0x0F) != (config_byte & 0x0F)) {
+    ESP_LOGW(TAG, "Config mismatch! Wrote 0x%02x, Read 0x%02x", config_byte, read_config);
+    return false;
+  }
+
+  return this->set_read_pointer_(DS248X_POINTER_STATUS);
+}
+
+// --- Channel Selection ---
+
+// Channel select codes: write code -> expected read code
+static constexpr uint8_t CHANNEL_WRITE_CODES[8] = {0xF0, 0xE1, 0xD2, 0xC3, 0xB4, 0xA5, 0x96, 0x87};
+static constexpr uint8_t CHANNEL_READ_CODES[8] = {0xB8, 0xB1, 0xAA, 0xA3, 0x9C, 0x95, 0x8E, 0x87};
+
+bool DS248xComponent::select_channel(uint8_t channel) {
+  if (this->channel_count_ <= 1)
+    return true;
+  if (channel >= this->channel_count_)
+    return false;
+
+  if (this->current_channel_ == channel)
+    return true;
+
+  if (!this->write_byte(DS248X_COMMAND_CHANNELSELECT, CHANNEL_WRITE_CODES[channel])) {
+    this->current_channel_ = -1;
+    return false;
+  }
+
+  uint8_t read_code;
+  if (this->read(&read_code, 1) != i2c::ERROR_OK) {
+    this->current_channel_ = -1;
+    return false;
+  }
+
+  if (read_code != CHANNEL_READ_CODES[channel]) {
+    ESP_LOGW(TAG, "Channel select failed! Expected 0x%02x, got 0x%02x", CHANNEL_READ_CODES[channel], read_code);
+    this->current_channel_ = -1;
+    return false;
+  }
+
+  if (!this->set_read_pointer_(DS248X_POINTER_STATUS))
+    return false;
+
+  this->current_channel_ = channel;
+  return true;
+}
+
+// --- 1-Wire Bus Operations ---
+
+bool DS248xComponent::ow_reset(bool &presence) {
+  if (!this->set_read_pointer_(DS248X_POINTER_STATUS))
+    return false;
+
+  uint8_t cmd = DS248X_COMMAND_RESETWIRE;
+  if (this->write(&cmd, 1) != i2c::ERROR_OK)
+    return false;
+
+  if (!this->wait_busy_()) {
+    ESP_LOGW(TAG, "ow_reset: wait busy failed");
+    return false;
+  }
+
+  uint8_t status;
+  if (this->read(&status, 1) != i2c::ERROR_OK) {
+    ESP_LOGW(TAG, "ow_reset: read status failed");
+    return false;
+  }
+
+  if (status & DS248X_STATUS_SD) {
+    ESP_LOGW(TAG, "Short detected on 1-Wire bus!");
+    return false;
+  }
+
+  presence = (status & DS248X_STATUS_PPD);
+  return true;
+}
+
+bool DS248xComponent::ow_write_byte(uint8_t byte) {
+  if (!this->set_read_pointer_(DS248X_POINTER_STATUS))
+    return false;
+
+  if (!this->wait_busy_()) {
+    ESP_LOGW(TAG, "Device busy before writing byte 0x%02x", byte);
+    return false;
+  }
+
+  uint8_t cmd[2] = {DS248X_COMMAND_WRITEBYTE, byte};
+  if (this->write(cmd, 2) != i2c::ERROR_OK) {
+    ESP_LOGW(TAG, "I2C write failed for byte 0x%02x", byte);
+    return false;
+  }
+
+  if (!this->wait_busy_()) {
+    ESP_LOGW(TAG, "Timeout waiting for write byte to complete!");
+    return false;
+  }
+
+  return true;
+}
+
+bool DS248xComponent::ow_read_byte(uint8_t &byte) {
+  if (!this->set_read_pointer_(DS248X_POINTER_STATUS))
+    return false;
+
+  uint8_t cmd = DS248X_COMMAND_READBYTE;
+  if (this->write(&cmd, 1) != i2c::ERROR_OK)
+    return false;
+
+  if (!this->wait_busy_())
+    return false;
+
+  if (!this->set_read_pointer_(DS248X_POINTER_DATA))
+    return false;
+
+  if (this->read(&byte, 1) != i2c::ERROR_OK)
+    return false;
+
+  return true;
+}
+
+bool DS248xComponent::search_triplet(bool search_direction, uint8_t &status) {
+  if (!this->set_read_pointer_(DS248X_POINTER_STATUS))
+    return false;
+
+  // DS248x Datasheet: 1-Wire Triplet command requires 2 bytes:
+  // Byte 1: Command code 0x78
+  // Byte 2: Direction byte (bit 7 = V, search direction if discrepancy)
+  uint8_t buffer[2] = {DS248X_COMMAND_TRIPLET, static_cast<uint8_t>(search_direction ? 0x80 : 0x00)};
+  if (this->write(buffer, 2) != i2c::ERROR_OK)
+    return false;
+
+  if (!this->wait_busy_())
+    return false;
+
+  if (this->read(&status, 1) != i2c::ERROR_OK)
+    return false;
+
+  return true;
+}
+
+}  // namespace esphome::ds248x

esphome/components/ds248x/ds248x.h

@@ -0,0 +1,133 @@
+#pragma once
+
+// DS248x I2C-to-1-Wire Bridge Family
+// Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ds2482-100.pdf
+// Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ds2482-800.pdf
+// Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ds2484.pdf
+
+#include "esphome/core/component.h"
+#include "esphome/core/hal.h"
+#include "esphome/components/i2c/i2c.h"
+
+namespace esphome::ds248x {
+
+// DS248x I2C Commands
+static constexpr uint8_t DS248X_COMMAND_RESET = 0xF0;
+static constexpr uint8_t DS248X_COMMAND_SETREADPTR = 0xE1;
+static constexpr uint8_t DS248X_COMMAND_WRITECONFIG = 0xD2;
+static constexpr uint8_t DS248X_COMMAND_CHANNELSELECT = 0xC3;
+static constexpr uint8_t DS248X_COMMAND_RESETWIRE = 0xB4;
+static constexpr uint8_t DS248X_COMMAND_WRITEBYTE = 0xA5;
+static constexpr uint8_t DS248X_COMMAND_READBYTE = 0x96;
+static constexpr uint8_t DS248X_COMMAND_TRIPLET = 0x78;
+static constexpr uint8_t DS2484_COMMAND_ADJUSTPORT = 0xC3;
+
+// DS2484 "Adjust 1-Wire Port" parameter codes (datasheet Table 6, control byte P[2:0])
+static constexpr uint8_t DS2484_PORT_PARAM_TRSTL = 0x0;
+static constexpr uint8_t DS2484_PORT_PARAM_TMSP = 0x1;
+static constexpr uint8_t DS2484_PORT_PARAM_TW0L = 0x2;
+static constexpr uint8_t DS2484_PORT_PARAM_TREC0 = 0x3;
+static constexpr uint8_t DS2484_PORT_PARAM_RWPU = 0x4;
+
+// DS248x Status Register Bits
+static constexpr uint8_t DS248X_STATUS_BUSY = 0x01;
+static constexpr uint8_t DS248X_STATUS_PPD = 0x02;
+static constexpr uint8_t DS248X_STATUS_SD = 0x04;
+static constexpr uint8_t DS248X_STATUS_RST = 0x10;
+static constexpr uint8_t DS248X_STATUS_SBR = 0x20;
+static constexpr uint8_t DS248X_STATUS_TSB = 0x40;
+static constexpr uint8_t DS248X_STATUS_DIR = 0x80;
+
+// DS248x Register Pointers
+static constexpr uint8_t DS248X_POINTER_STATUS = 0xF0;
+static constexpr uint8_t DS248X_POINTER_DATA = 0xE1;
+static constexpr uint8_t DS248X_POINTER_CONFIG = 0xC3;
+
+// DS248x Configuration Bits
+static constexpr uint8_t DS248X_CONFIG_ACTIVE_PULLUP = 0x01;
+
+/**
+ * @brief DS248x I2C-to-1-Wire Bridge Component.
+ *
+ * This component manages the DS248x chip (DS2482-100, DS2482-800, DS2484).
+ * It provides low-level 1-Wire bus operations via I2C.
+ *
+ * Usage: Configure DS248xOneWireBus instances for each channel.
+ * These buses implement the one_wire::OneWireBus interface for compatibility
+ * with all existing 1-Wire device components (dallas_temp, etc.).
+ */
+class DS248xComponent : public Component, public i2c::I2CDevice {
+ public:
+  void setup() override;
+  void dump_config() override;
+  void on_shutdown() override;
+  float get_setup_priority() const override { return setup_priority::BUS; }
+
+  void set_sleep_pin(InternalGPIOPin *pin) { this->sleep_pin_ = pin; }
+  void set_bus_sleep(bool enabled) { this->bus_sleep_ = enabled; }
+  void set_hub_sleep(bool enabled) { this->hub_sleep_ = enabled; }
+  void set_channel_count(uint8_t count) { this->channel_count_ = count; }
+  void set_active_pullup(bool enabled) { this->active_pullup_ = enabled; }
+
+  // DS2484 Timing Parameters
+  void set_val_trstl(uint8_t val) {
+    this->ds2484_trstl_ = val;
+    this->ds2484_mode_ = true;
+  }
+  void set_val_tmsp(uint8_t val) {
+    this->ds2484_tmsp_ = val;
+    this->ds2484_mode_ = true;
+  }
+  void set_val_tw0l(uint8_t val) {
+    this->ds2484_tw0l_ = val;
+    this->ds2484_mode_ = true;
+  }
+  void set_val_trec0(uint8_t val) {
+    this->ds2484_trec0_ = val;
+    this->ds2484_mode_ = true;
+  }
+  void set_val_rwpu(uint8_t val) {
+    this->ds2484_rwpu_ = val;
+    this->ds2484_mode_ = true;
+  }
+
+  /// Get the channel count (1 for DS2482-100/DS2484, 8 for DS2482-800)
+  uint8_t get_channel_count() const { return this->channel_count_; }
+
+  // --- Core 1-Wire API (used by DS248xOneWireBus) ---
+  bool select_channel(uint8_t channel);
+  bool ow_reset(bool &presence);
+  bool ow_write_byte(uint8_t byte);
+  bool ow_read_byte(uint8_t &byte);
+
+  // --- Search support (used by DS248xOneWireBus) ---
+  bool search_triplet(bool search_direction, uint8_t &status);
+
+ protected:
+  InternalGPIOPin *sleep_pin_{nullptr};
+  uint8_t channel_count_ = 1;
+  bool bus_sleep_{false};
+  bool hub_sleep_{false};
+  bool active_pullup_ = false;
+
+  // DS2484 Config
+  bool ds2484_mode_ = false;
+  static constexpr uint8_t DS2484_PARAM_UNSET = 0xFF;
+  uint8_t ds2484_trstl_{DS2484_PARAM_UNSET};
+  uint8_t ds2484_tmsp_{DS2484_PARAM_UNSET};
+  uint8_t ds2484_tw0l_{DS2484_PARAM_UNSET};
+  uint8_t ds2484_trec0_{DS2484_PARAM_UNSET};
+  uint8_t ds2484_rwpu_{DS2484_PARAM_UNSET};
+
+  int8_t current_channel_{-1};
+
+  // Internal helpers
+  bool set_read_pointer_(uint8_t ptr);
+  bool wait_busy_();
+  bool device_reset_();
+  bool device_configure_();
+  bool configure_ds2484_port_(uint8_t param, uint8_t val);
+  bool write_config_();
+};
+
+}  // namespace esphome::ds248x

esphome/components/ds248x/ds248x_one_wire_bus.cpp

@@ -0,0 +1,171 @@
+#include "ds248x_one_wire_bus.h"
+#include "ds248x.h"
+#include "esphome/core/log.h"
+
+namespace esphome::ds248x {
+
+static const char *const TAG = "ds248x.one_wire";
+
+void DS248xOneWireBus::setup() {
+  ESP_LOGCONFIG(TAG, "Setting up DS248x 1-Wire Bus (Channel %d)...", this->channel_);
+
+  // Parent setup happens in DS248xComponent::setup()
+  // We just need to scan for devices on this channel
+  if (!this->ensure_channel_()) {
+    ESP_LOGE(TAG, "Failed to select channel %d during setup", this->channel_);
+    this->mark_failed();
+    return;
+  }
+
+  // Perform device search on this channel
+  this->search();
+
+  ESP_LOGCONFIG(TAG, "Found %zu devices on channel %d", this->devices_.size(), this->channel_);
+}
+
+void DS248xOneWireBus::dump_config() {
+  ESP_LOGCONFIG(TAG, "DS248x 1-Wire Bus (Channel %d):", this->channel_);
+  this->dump_devices_(TAG);
+}
+
+bool DS248xOneWireBus::ensure_channel_() {
+  if (this->parent_ == nullptr) {
+    ESP_LOGE(TAG, "Parent not set!");
+    return false;
+  }
+  return this->parent_->select_channel(this->channel_);
+}
+
+int DS248xOneWireBus::reset_int() {
+  if (!this->ensure_channel_()) {
+    return -1;
+  }
+
+  bool presence = false;
+  if (!this->parent_->ow_reset(presence)) {
+    return -1;
+  }
+  return presence ? 1 : 0;
+}
+
+void DS248xOneWireBus::write8(uint8_t val) {
+  if (!this->ensure_channel_()) {
+    return;
+  }
+  if (!this->parent_->ow_write_byte(val)) {
+    ESP_LOGE(TAG, "Failed to write byte 0x%02X on channel %d", val, this->channel_);
+  }
+}
+
+void DS248xOneWireBus::write64(uint64_t val) {
+  if (!this->ensure_channel_()) {
+    return;
+  }
+  for (uint8_t i = 0; i < 8; i++) {
+    uint8_t byte = static_cast<uint8_t>(val >> (i * 8));
+    if (!this->parent_->ow_write_byte(byte)) {
+      ESP_LOGE(TAG, "Failed to write byte %d/8 (0x%02X) on channel %d - aborting write64", i + 1, byte, this->channel_);
+      return;  // Stop writing to prevent sending corrupted data
+    }
+  }
+}
+
+uint8_t DS248xOneWireBus::read8() {
+  if (!this->ensure_channel_()) {
+    return 0;
+  }
+  uint8_t value = 0;
+  if (!this->parent_->ow_read_byte(value)) {
+    ESP_LOGE(TAG, "Failed to read byte on channel %d", this->channel_);
+  }
+  return value;
+}
+
+uint64_t DS248xOneWireBus::read64() {
+  if (!this->ensure_channel_()) {
+    return 0;
+  }
+  uint64_t value = 0;
+  for (uint8_t i = 0; i < 8; i++) {
+    uint8_t byte = 0;
+    if (!this->parent_->ow_read_byte(byte)) {
+      ESP_LOGE(TAG, "Failed to read byte %d/8 on channel %d - returning partial data", i + 1, this->channel_);
+      return value;  // Return partial data to avoid blocking, caller should validate
+    }
+    value |= (static_cast<uint64_t>(byte) << (i * 8));
+  }
+  return value;
+}
+
+void DS248xOneWireBus::reset_search() {
+  this->search_last_discrepancy_ = 0;
+  this->search_last_device_flag_ = false;
+  this->search_address_ = 0;
+}
+
+uint64_t DS248xOneWireBus::search_int() {
+  if (!this->ensure_channel_()) {
+    return 0;
+  }
+
+  if (this->search_last_device_flag_) {
+    return 0;
+  }
+
+  uint8_t last_zero = 0;
+  uint64_t address = this->search_address_;
+
+  // Iterate through all 64 bits
+  for (uint8_t bit_number = 1; bit_number <= 64; bit_number++) {
+    uint64_t bit_mask = 1ULL << (bit_number - 1);
+
+    // Determine search direction
+    bool search_direction;
+    if (bit_number < this->search_last_discrepancy_) {
+      search_direction = (address & bit_mask) != 0;
+    } else {
+      search_direction = (bit_number == this->search_last_discrepancy_);
+    }
+
+    // Perform triplet operation
+    uint8_t status = 0;
+    if (!this->parent_->search_triplet(search_direction, status)) {
+      ESP_LOGW(TAG, "1-Wire triplet failed at bit %d on channel %d - aborting search", bit_number, this->channel_);
+      this->reset_search();
+      return 0;
+    }
+
+    bool id_bit = (status & DS248X_STATUS_SBR) != 0;
+    bool cmp_id_bit = (status & DS248X_STATUS_TSB) != 0;
+    bool dir_taken = (status & DS248X_STATUS_DIR) != 0;
+
+    if (id_bit && cmp_id_bit) {
+      // No devices participating
+      this->reset_search();
+      return 0;
+    }
+
+    if (!id_bit && !cmp_id_bit && !dir_taken) {
+      // Discrepancy, went 0 - record position
+      last_zero = bit_number;
+    }
+
+    // Update address based on direction taken
+    if (dir_taken) {
+      address |= bit_mask;
+    } else {
+      address &= ~bit_mask;
+    }
+  }
+
+  // Search successful
+  this->search_last_discrepancy_ = last_zero;
+  if (last_zero == 0) {
+    this->search_last_device_flag_ = true;
+  }
+  this->search_address_ = address;
+
+  return address;
+}
+
+}  // namespace esphome::ds248x

esphome/components/ds248x/ds248x_one_wire_bus.h

@@ -0,0 +1,57 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/components/one_wire/one_wire_bus.h"
+
+namespace esphome::ds248x {
+
+class DS248xComponent;
+
+/**
+ * @brief OneWireBus implementation for DS248x I2C-to-1-Wire bridges.
+ *
+ * This class wraps the DS248xComponent to provide the one_wire::OneWireBus interface,
+ * enabling compatibility with all existing 1-Wire device components (dallas_temp, etc.).
+ *
+ * For DS2482-800, multiple instances of this class can be created (one per channel).
+ * For DS2482-100/DS2484, a single instance is used.
+ */
+class DS248xOneWireBus : public one_wire::OneWireBus, public Component {
+ public:
+  void setup() override;
+  void dump_config() override;
+  float get_setup_priority() const override { return setup_priority::BUS - 1.0f; }
+
+  /// Set the parent DS248x component
+  void set_parent(DS248xComponent *parent) { this->parent_ = parent; }
+
+  /// Set the 1-Wire channel (0-7, only relevant for DS2482-800)
+  void set_channel(uint8_t channel) { this->channel_ = channel; }
+
+  /// Get the channel number
+  uint8_t get_channel() const { return this->channel_; }
+
+  // OneWireBus interface implementation
+  int reset_int() override;
+  void write8(uint8_t val) override;
+  void write64(uint64_t val) override;
+  uint8_t read8() override;
+  uint64_t read64() override;
+
+ protected:
+  void reset_search() override;
+  uint64_t search_int() override;
+
+  /// Select the channel on the DS248x before any 1-Wire operation
+  bool ensure_channel_();
+
+  DS248xComponent *parent_{nullptr};
+  uint8_t channel_{0};
+
+  // Search state
+  uint64_t search_address_{0};
+  uint8_t search_last_discrepancy_{0};
+  bool search_last_device_flag_{false};
+};
+
+}  // namespace esphome::ds248x

esphome/components/ds248x/one_wire.py

@@ -0,0 +1,56 @@
+"""DS248x 1-Wire Bus Platform.
+
+This platform creates one_wire bus instances backed by a DS248x I2C-to-1-Wire bridge.
+It supports DS2482-100/101 (single channel), DS2482-800 (8 channels), and DS2484 (single channel).
+
+For multi-channel devices (DS2482-800), create one platform entry per channel.
+Each entry becomes a separate one_wire bus that can be used by dallas_temp and other 1-Wire devices.
+"""
+
+from esphome import final_validate as fv
+import esphome.codegen as cg
+from esphome.components.one_wire import OneWireBus
+import esphome.config_validation as cv
+from esphome.const import CONF_CHANNEL, CONF_ID
+
+from . import CONF_DS248X_ID, DS248xComponent, ds248x_ns, get_channel_count
+
+CODEOWNERS = ["@tomwellnitz"]
+DEPENDENCIES = ["ds248x"]
+
+DS248xOneWireBus = ds248x_ns.class_("DS248xOneWireBus", OneWireBus, cg.Component)
+
+CONFIG_SCHEMA = cv.Schema(
+    {
+        cv.GenerateID(): cv.declare_id(DS248xOneWireBus),
+        cv.GenerateID(CONF_DS248X_ID): cv.use_id(DS248xComponent),
+        cv.Optional(CONF_CHANNEL, default=0): cv.int_range(min=0, max=7),
+    }
+).extend(cv.COMPONENT_SCHEMA)
+
+
+def _final_validate(config):
+    """Validate that the channel is within the parent's channel count."""
+    fconf = fv.full_config.get()
+    path = fconf.get_path_for_id(config[CONF_DS248X_ID])[:-1]
+    parent_config = fconf.get_config_for_path(path)
+    channel_count = get_channel_count(parent_config)
+    channel = config[CONF_CHANNEL]
+
+    if channel >= channel_count:
+        raise cv.Invalid(
+            f"Channel {channel} is invalid for DS248x with {channel_count} channel(s). "
+            f"Valid range: 0-{channel_count - 1}"
+        )
+
+
+FINAL_VALIDATE_SCHEMA = _final_validate
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    await cg.register_component(var, config)
+
+    parent = await cg.get_variable(config[CONF_DS248X_ID])
+    cg.add(var.set_parent(parent))
+    cg.add(var.set_channel(config[CONF_CHANNEL]))

tests/components/ds248x/common.yaml

@@ -0,0 +1,115 @@
+# Combined DS248x test covering all chip variants and options:
+#   - DS2482-100: active pullup, multiple sensors + index access
+#   - DS2482-101: sleep pin, bus_sleep / hub_sleep
+#   - DS2482-800: all 8 channels
+#   - DS2484:     adjustable 1-Wire timing + RWPU pullup resistor selection
+ds248x:
+  - id: ds2482_100
+    address: 0x18
+    type: ds2482-100
+    active_pullup: true
+  - id: ds2482_101
+    address: 0x19
+    type: ds2482-101
+    active_pullup: true
+    sleep_pin:
+      number: GPIO12
+      inverted: false
+    bus_sleep: true
+    hub_sleep: true
+  - id: ds2482_800
+    address: 0x1a
+    type: ds2482-800
+    active_pullup: true
+  - id: ds2484_hub
+    address: 0x1b
+    type: ds2484
+    active_pullup: true
+    # DS2484-specific 1-Wire timing parameters (optional fine-tuning)
+    reset_low_time: 8              # tRSTL: Reset low time
+    master_sample_time: 8         # tMSP: Master sample point
+    write_0_low_time: 8           # tW0L: Write-0 low time
+    recovery_time: 8              # tREC0: Recovery time
+    active_pullup_resistance: 1000ohm  # RWPU: weak pullup resistor selection
+
+one_wire:
+  - platform: ds248x
+    ds248x_id: ds2482_100
+    channel: 0
+    id: ow_100
+  - platform: ds248x
+    ds248x_id: ds2482_101
+    channel: 0
+    id: ow_101
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 0
+    id: ow_800_0
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 1
+    id: ow_800_1
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 2
+    id: ow_800_2
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 3
+    id: ow_800_3
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 4
+    id: ow_800_4
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 5
+    id: ow_800_5
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 6
+    id: ow_800_6
+  - platform: ds248x
+    ds248x_id: ds2482_800
+    channel: 7
+    id: ow_800_7
+  - platform: ds248x
+    ds248x_id: ds2484_hub
+    channel: 0
+    id: ow_2484
+
+sensor:
+  # DS2482-100: explicit address + index-based access on the same bus
+  - platform: dallas_temp
+    one_wire_id: ow_100
+    address: 0x1c0000031edd2a28
+    name: Temp 100 by address
+    resolution: 12
+  - platform: dallas_temp
+    one_wire_id: ow_100
+    index: 0
+    name: Temp 100 by index
+  # DS2482-101 (sleep variant)
+  - platform: dallas_temp
+    one_wire_id: ow_101
+    address: 0x578295491f64ff28
+    name: Temp 101
+  # DS2482-800: sensors on a few of the eight channels
+  - platform: dallas_temp
+    one_wire_id: ow_800_0
+    address: 0x1c0000031edd2a28
+    name: Temp 800 CH0
+  - platform: dallas_temp
+    one_wire_id: ow_800_3
+    index: 0
+    name: Temp 800 CH3 by index
+  - platform: dallas_temp
+    one_wire_id: ow_800_7
+    address: 0x2800000123456789
+    name: Temp 800 CH7
+  # DS2484 (adjustable timing)
+  - platform: dallas_temp
+    one_wire_id: ow_2484
+    address: 0x1c0000031edd2a28
+    name: Temp 2484
+    resolution: 12

tests/components/ds248x/test.esp32-ard.yaml

@@ -0,0 +1,4 @@
+packages:
+  i2c: !include ../../test_build_components/common/i2c/esp32-ard.yaml
+
+<<: !include common.yaml

tests/components/ds248x/test.esp32-idf.yaml

@@ -0,0 +1,4 @@
+packages:
+  i2c: !include ../../test_build_components/common/i2c/esp32-idf.yaml
+
+<<: !include common.yaml

tests/components/ds248x/test.esp8266-ard.yaml

@@ -0,0 +1,4 @@
+packages:
+  i2c: !include ../../test_build_components/common/i2c/esp8266-ard.yaml
+
+<<: !include common.yaml

tests/components/ds248x/test.rp2040-ard.yaml

@@ -0,0 +1,4 @@
+packages:
+  i2c: !include ../../test_build_components/common/i2c/rp2040-ard.yaml
+
+<<: !include common.yaml