Merge branch 'gpio-reset-pulse' into gpio-reset-pulse-migrate

Call sites read as pulse_reset(pin, {.high_before_ms = 1, .low_ms = 10}) instead of bare
positional numbers. The inline wrapper passes the fields in registers, so the build is
byte identical to the positional form.

esphome/components/ade7880/ade7880.cpp

@@ -297,9 +297,7 @@ void ADE7880::init_device_() {
 void ADE7880::reset_device_() {
   if (this->reset_pin_ != nullptr) {
     ESP_LOGD(TAG, "Reset device using RESET pin");
-    this->reset_pin_->digital_write(false);
-    delay(1);
-    this->reset_pin_->digital_write(true);
+    pulse_reset(this->reset_pin_, {.low_ms = 1});
   } else {
     ESP_LOGD(TAG, "Reset device using SWRST command");
     this->write_u16_register16_(CONFIG, CONFIG_SWRST);

esphome/components/axs15231/touchscreen/axs15231_touchscreen.cpp

@@ -16,13 +16,7 @@ constexpr static const uint8_t AXS_READ_TOUCHPAD[11] = {0xb5, 0xab, 0xa5, 0x5a,
   }
 
 void AXS15231Touchscreen::setup() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(false);
-    delay(5);
-    this->reset_pin_->digital_write(true);
-    delay(10);
-  }
+  pulse_reset(this->reset_pin_, {.low_ms = 5, .high_after_ms = 10});
   if (this->interrupt_pin_ != nullptr) {
     this->interrupt_pin_->pin_mode(gpio::FLAG_INPUT);
     this->interrupt_pin_->setup();

esphome/components/cst226/touchscreen/cst226_touchscreen.cpp

@@ -6,12 +6,7 @@ ESPHOME_LOG_TAG(TAG, "cst226.touchscreen");
 
 void CST226Touchscreen::setup() {
   if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(5);
-    this->reset_pin_->digital_write(false);
-    delay(5);
-    this->reset_pin_->digital_write(true);
+    pulse_reset(this->reset_pin_, {.high_before_ms = 5, .low_ms = 5});
     this->set_timeout(30, [this] { this->continue_setup_(); });
   } else {
     this->continue_setup_();

esphome/components/cst328/touchscreen/cst328_touchscreen.cpp

@@ -43,9 +43,7 @@ void CST328Touchscreen::setup() {
 }
 
 void CST328Touchscreen::reset_device_() {
-  this->reset_pin_->digital_write(false);
-  delay(5);
-  this->reset_pin_->digital_write(true);
+  pulse_reset(this->reset_pin_, {.low_ms = 5});
   this->set_timeout(CST328_TRANSITION_TIMEOUT, [this] { this->continue_setup_(); });
 }
 

esphome/components/cst816/touchscreen/cst816_touchscreen.cpp

@@ -52,12 +52,7 @@ void CST816Touchscreen::continue_setup_() {
 
 void CST816Touchscreen::setup() {
   if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(5);
-    this->reset_pin_->digital_write(false);
-    delay(5);
-    this->reset_pin_->digital_write(true);
+    pulse_reset(this->reset_pin_, {.high_before_ms = 5, .low_ms = 5});
     this->set_timeout(30, [this] { this->continue_setup_(); });
   } else {
     this->continue_setup_();

esphome/components/cst9220/touchscreen/cst9220_touchscreen.cpp

@@ -10,14 +10,7 @@ static constexpr uint32_t REREAD_TIMEOUT_ID = 1;
 static constexpr uint32_t REREAD_DELAY_MS = 20;
 
 void CST9220Touchscreen::setup() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(5);
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    this->reset_pin_->digital_write(true);
-  }
+  pulse_reset(this->reset_pin_, {.high_before_ms = 5, .low_ms = 10});
   // Wait for the controller to leave its bootloader before talking to it.
   this->set_timeout(30, [this] { this->continue_setup_(); });
 }

esphome/components/ektf2232/touchscreen/ektf2232.cpp

@@ -20,9 +20,7 @@ void EKTF2232Touchscreen::setup() {
 
   this->attach_interrupt_(this->interrupt_pin_, gpio::INTERRUPT_FALLING_EDGE);
 
-  this->reset_pin_->setup();
-
-  this->hard_reset_();
+  pulse_reset(this->reset_pin_, {.low_ms = 15, .high_after_ms = 15});
   if (!this->soft_reset_()) {
     ESP_LOGE(TAG, "Failed to soft reset EKT2232!");
     this->interrupt_pin_->detach_interrupt();
@@ -96,13 +94,6 @@ bool EKTF2232Touchscreen::get_power_state() {
   return (received[1] >> 3) & 1;
 }
 
-void EKTF2232Touchscreen::hard_reset_() {
-  this->reset_pin_->digital_write(false);
-  delay(15);
-  this->reset_pin_->digital_write(true);
-  delay(15);
-}
-
 bool EKTF2232Touchscreen::soft_reset_() {
   auto err = this->write(SOFT_RESET_CMD, 4);
   if (err != i2c::ERROR_OK)

esphome/components/ektf2232/touchscreen/ektf2232.h

@@ -22,7 +22,6 @@ class EKTF2232Touchscreen final : public Touchscreen, public i2c::I2CDevice {
   bool get_power_state();
 
  protected:
-  void hard_reset_();
   bool soft_reset_();
   void update_touches() override;
 

esphome/components/epaper_spi/epaper_spi_jd79660.cpp

@@ -72,9 +72,7 @@ bool EPaperJD79660::reset() {
 
       // As commented on SLEEP_MS_RESET1: Reset pulse must happen within time window.
       // So do not use FSM loop, and avoid other calls/logs during pulse below.
-      this->reset_pin_->digital_write(false);
-      delay(SLEEP_MS_RESET1);
-      this->reset_pin_->digital_write(true);
+      pulse_reset(this->reset_pin_, {.low_ms = SLEEP_MS_RESET1});
 
       this->reset_duration_ = SLEEP_MS_RESET2;
       this->step_ = FSMState::RESET_STEP2_IDLECHECK;

esphome/components/ft63x6/ft63x6.cpp

@@ -34,10 +34,7 @@ void FT63X6Touchscreen::setup() {
     this->attach_interrupt_(this->interrupt_pin_, gpio::INTERRUPT_ANY_EDGE);
   }
 
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->hard_reset_();
-  }
+  pulse_reset(this->reset_pin_, {.low_ms = 10});
 
   // Get touch resolution
   if (this->x_raw_max_ == this->x_raw_min_) {
@@ -57,14 +54,6 @@ void FT63X6Touchscreen::setup() {
   this->write_byte(FT6X36_ADDR_TOUCHRATE_ACTIVE, 0x0E);
 }
 
-void FT63X6Touchscreen::hard_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    this->reset_pin_->digital_write(true);
-  }
-}
-
 void FT63X6Touchscreen::dump_config() {
   ESP_LOGCONFIG(TAG, "FT63X6 Touchscreen:");
   LOG_I2C_DEVICE(this);

esphome/components/ft63x6/ft63x6.h

@@ -27,7 +27,6 @@ class FT63X6Touchscreen final : public Touchscreen, public i2c::I2CDevice {
   void set_threshold(uint8_t threshold) { this->threshold_ = threshold; }
 
  protected:
-  void hard_reset_();
   void update_touches() override;
 
   InternalGPIOPin *interrupt_pin_{nullptr};

esphome/components/gsl3670/gsl3670_touchscreen.cpp

@@ -83,13 +83,7 @@ void GSL3670Touchscreen::update_touches() {
 void GSL3670Touchscreen::clear_reg_() {
   ESP_LOGD(TAG, "clear_reg");
 
-  // GPIO reset pulse
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->digital_write(false);
-    delay(1);
-    this->reset_pin_->digital_write(true);
-    delay(5);
-  }
+  pulse_reset(this->reset_pin_, {.low_ms = 1, .high_after_ms = 5});
 
   this->write_reg8_(0x88, 0x01);
   // delay(5);
@@ -106,12 +100,7 @@ void GSL3670Touchscreen::clear_reg_() {
 void GSL3670Touchscreen::reset_() {
   ESP_LOGD(TAG, "reset");
 
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->digital_write(false);
-    delay(1);
-    this->reset_pin_->digital_write(true);
-    delay(5);
-  }
+  pulse_reset(this->reset_pin_, {.low_ms = 1, .high_after_ms = 5});
 
   this->write_reg8_(0xe4, 0x04);
 

esphome/components/icnt86/icnt86.cpp

@@ -19,12 +19,7 @@ void ICNT86Touchscreen::setup() {
   }
 
   // Perform reset if necessary
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    this->reset_pin_->digital_write(true);
-  }
+  pulse_reset(this->reset_pin_, {.low_ms = 10});
 
   if (this->x_raw_max_ == this->x_raw_min_) {
     this->x_raw_max_ = this->display_->get_native_width();

esphome/components/mipi_dsi/mipi_dsi.cpp

@@ -107,12 +107,7 @@ void MipiDsi::setup() {
   }
 #endif
   if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(5);
-    this->reset_pin_->digital_write(false);
-    delay(5);
-    this->reset_pin_->digital_write(true);
+    pulse_reset(this->reset_pin_, {.high_before_ms = 5, .low_ms = 5});
   } else {
     esp_lcd_panel_io_tx_param(this->io_handle_, SW_RESET_CMD, nullptr, 0);
   }

esphome/components/mipi_rgb/mipi_rgb.cpp

@@ -33,14 +33,7 @@ void MipiRgb::setup_enables_() {
     }
     delay(10);
   }
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(5);
-    this->reset_pin_->digital_write(false);
-    delay(5);
-    this->reset_pin_->digital_write(true);
-  }
+  pulse_reset(this->reset_pin_, {.high_before_ms = 5, .low_ms = 5});
 }
 
 #ifdef USE_SPI

esphome/components/mipi_spi/mipi_spi.h

@@ -151,15 +151,8 @@ class MipiSpi : public display::Display,
       pin->setup();
       pin->digital_write(true);
     }
-    if (this->reset_pin_ != nullptr) {
-      this->reset_pin_->setup();
-      this->reset_pin_->digital_write(true);
-      delay(5);
-      this->reset_pin_->digital_write(false);
-      delay(5);
-      this->reset_pin_->digital_write(true);
-      // required delay after reset is already in the init sequence, don't duplicate
-    }
+    // required delay after reset is already in the init sequence, don't duplicate
+    pulse_reset(this->reset_pin_, {.high_before_ms = 5, .low_ms = 5});
 
     // need to know when the display is ready for SLPOUT command - will be 120ms after reset
     auto when = millis() + 120;

esphome/components/pcd8544/pcd_8544.cpp

@@ -9,23 +9,10 @@ ESPHOME_LOG_TAG(TAG, "pcd_8544");
 
 void PCD8544::setup_pins_() {
   this->spi_setup();
-  this->init_reset_();
+  pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10});
   this->dc_pin_->setup();
 }
 
-void PCD8544::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
-
 void PCD8544::initialize() {
   this->init_internal_(this->get_buffer_length_());
 

esphome/components/pcd8544/pcd_8544.h

@@ -57,8 +57,6 @@ class PCD8544 final : public display::DisplayBuffer,
 
   void setup_pins_();
 
-  void init_reset_();
-
   size_t get_buffer_length_();
 
   void start_command_();

esphome/components/sh1122_base/sh1122_base.cpp

@@ -122,18 +122,7 @@ void SH1122::fill(Color color) {
   const uint8_t fill = (color4 & SH1122_COLORMASK) | ((color4 & SH1122_COLORMASK) << SH1122_COLORSHIFT);
   memset(this->buffer_, fill, this->get_buffer_length_());
 }
-void SH1122::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void SH1122::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 const LogString *SH1122::model_str_() {
   switch (this->model_) {
     case SH1122_MODEL_256_64:

esphome/components/ssd1306_base/ssd1306_base.cpp

@@ -355,18 +355,7 @@ void SSD1306::fill(Color color) {
   for (uint32_t i = 0; i < this->get_buffer_length_(); i++)
     this->buffer_[i] = fill;
 }
-void SSD1306::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void SSD1306::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 const LogString *SSD1306::model_str_() {
   return ModelStrings::get_log_str(static_cast<uint8_t>(this->model_), ModelStrings::LAST_INDEX);
 }

esphome/components/ssd1322_base/ssd1322_base.cpp

@@ -184,18 +184,7 @@ void SSD1322::fill(Color color) {
   for (uint32_t i = 0; i < this->get_buffer_length_(); i++)
     this->buffer_[i] = fill;
 }
-void SSD1322::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void SSD1322::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 const char *SSD1322::model_str_() {
   switch (this->model_) {
     case SSD1322_MODEL_256_64:

esphome/components/ssd1325_base/ssd1325_base.cpp

@@ -211,18 +211,7 @@ void SSD1325::fill(Color color) {
   for (uint32_t i = 0; i < this->get_buffer_length_(); i++)
     this->buffer_[i] = fill;
 }
-void SSD1325::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void SSD1325::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 const char *SSD1325::model_str_() {
   switch (this->model_) {
     case SSD1325_MODEL_128_32:

esphome/components/ssd1327_base/ssd1327_base.cpp

@@ -160,18 +160,7 @@ void SSD1327::fill(Color color) {
   for (uint32_t i = 0; i < this->get_buffer_length_(); i++)
     this->buffer_[i] = fill;
 }
-void SSD1327::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void SSD1327::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 const char *SSD1327::model_str_() {
   switch (this->model_) {
     case SSD1327_MODEL_128_128:

esphome/components/ssd1331_base/ssd1331_base.cpp

@@ -142,17 +142,6 @@ void SSD1331::fill(Color color) {
     }
   }
 }
-void SSD1331::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void SSD1331::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 
 }  // namespace esphome::ssd1331_base

esphome/components/ssd1351_base/ssd1351_base.cpp

@@ -174,18 +174,7 @@ void SSD1351::fill(Color color) {
     }
   }
 }
-void SSD1351::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void SSD1351::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 const char *SSD1351::model_str_() {
   switch (this->model_) {
     case SSD1351_MODEL_128_96:

esphome/components/st7123/touchscreen/st7123_touchscreen.cpp

@@ -9,12 +9,8 @@ ESPHOME_LOG_TAG(TAG, "st7123.touchscreen");
 
 void ST7123Touchscreen::setup() {
   if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(5);
-    this->reset_pin_->digital_write(false);  // TP_RESX is active low, assert for at least tRSTW (2ms)
-    delay(5);
-    this->reset_pin_->digital_write(true);
+    // TP_RESX is active low, assert for at least tRSTW (2ms)
+    pulse_reset(this->reset_pin_, {.high_before_ms = 5, .low_ms = 5});
     // The controller needs up to 20ms to initialize after reset before it can be accessed.
     this->setup_time_ = millis() + 30;
   }

esphome/components/st7567_base/st7567_base.cpp

@@ -137,18 +137,7 @@ void ST7567::fill(Color color) {
   memset(buffer_, fill, this->get_buffer_length_());
 }
 
-void ST7567::init_reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_pin_->digital_write(true);
-    delay(1);
-    // Trigger Reset
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    // Wake up
-    this->reset_pin_->digital_write(true);
-  }
-}
+void ST7567::init_reset_() { pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}); }
 
 const char *ST7567::model_str_() { return "ST7567 128x64"; }
 

esphome/components/tt21100/touchscreen/tt21100.cpp

@@ -54,10 +54,7 @@ void TT21100Touchscreen::setup() {
   }
 
   // Perform reset if necessary
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->setup();
-    this->reset_();
-  }
+  pulse_reset(this->reset_pin_, {.low_ms = 10, .high_after_ms = 10});
 
   // Update display dimensions if they were updated during display setup
   if (this->display_ != nullptr) {
@@ -122,15 +119,6 @@ void TT21100Touchscreen::update_touches() {
   }
 }
 
-void TT21100Touchscreen::reset_() {
-  if (this->reset_pin_ != nullptr) {
-    this->reset_pin_->digital_write(false);
-    delay(10);
-    this->reset_pin_->digital_write(true);
-    delay(10);
-  }
-}
-
 void TT21100Touchscreen::dump_config() {
   ESP_LOGCONFIG(TAG, "TT21100 Touchscreen:");
   LOG_I2C_DEVICE(this);

esphome/components/tt21100/touchscreen/tt21100.h

@@ -28,8 +28,6 @@ class TT21100Touchscreen final : public Touchscreen, public i2c::I2CDevice {
   void register_button_listener(TT21100ButtonListener *listener) { this->button_listeners_.push_back(listener); }
 
  protected:
-  void reset_();
-
   void update_touches() override;
 
   InternalGPIOPin *interrupt_pin_;

esphome/core/gpio.cpp

@@ -1,4 +1,5 @@
 #include "esphome/core/gpio.h"
+#include "esphome/core/hal.h"
 #include "esphome/core/log.h"
 
 namespace esphome {
@@ -18,4 +19,18 @@ void log_pin(const char *tag, const char *prefix, GPIOPin *pin) {
 }
 #endif
 
+namespace internal {
+void pulse_reset_ms(GPIOPin *pin, uint32_t high_before_ms, uint32_t low_ms, uint32_t high_after_ms) {
+  if (pin == nullptr)
+    return;
+  pin->setup();
+  const uint32_t waits[] = {high_before_ms, low_ms, high_after_ms};
+  // Level for each step is high, low, high; a zero high_before_ms skips the first step
+  for (size_t i = high_before_ms == 0; i < 3; i++) {
+    pin->digital_write(i != 1);
+    delay(waits[i]);
+  }
+}
+}  // namespace internal
+
 }  // namespace esphome

esphome/core/gpio_pin.h

@@ -144,4 +144,24 @@ void log_pin(const char *tag, const __FlashStringHelper *prefix, GPIOPin *pin);
 void log_pin(const char *tag, const char *prefix, GPIOPin *pin);
 #endif
 
+/// Waveform for pulse_reset(): high, low, then high again. Name the fields at the call site, e.g.
+/// pulse_reset(this->reset_pin_, {.high_before_ms = 1, .low_ms = 10}).
+struct ResetPulse {
+  uint32_t high_before_ms{0};  ///< Drive high this long first; skipped when 0
+  uint32_t low_ms{0};          ///< Hold the pin low (in reset) this long
+  uint32_t high_after_ms{0};   ///< Wait this long after releasing the pin
+};
+
+namespace internal {
+/// Out-of-line body of pulse_reset(); call that instead.
+void pulse_reset_ms(GPIOPin *pin, uint32_t high_before_ms, uint32_t low_ms, uint32_t high_after_ms);
+}  // namespace internal
+
+/// Set up an active-low reset pin and drive it through \p pulse. Blocks for the whole sequence;
+/// does nothing when pin is null. Inline so the fields reach pulse_reset_ms() in registers
+/// (RISC-V would otherwise pass the struct by reference).
+ESPHOME_ALWAYS_INLINE inline void pulse_reset(GPIOPin *pin, ResetPulse pulse) {
+  internal::pulse_reset_ms(pin, pulse.high_before_ms, pulse.low_ms, pulse.high_after_ms);
+}
+
 }  // namespace esphome

tests/components/core/test_pulse_reset.cpp

@@ -0,0 +1,51 @@
+#include <gtest/gtest.h>
+
+#include <string>
+#include <vector>
+
+#include "esphome/core/gpio.h"
+#include "esphome/core/hal.h"
+
+namespace esphome::core::testing {
+
+class RecordingPin : public GPIOPin {
+ public:
+  void setup() override { this->events += 'S'; }
+  void pin_mode(gpio::Flags /*flags*/) override {}
+  gpio::Flags get_flags() const override { return gpio::FLAG_OUTPUT; }
+  bool digital_read() override { return false; }
+  void digital_write(bool value) override {
+    this->events += value ? 'H' : 'L';
+    this->write_ms.push_back(millis());
+  }
+
+  std::string events;
+  std::vector<uint32_t> write_ms;
+};
+
+TEST(PulseReset, NullPinIsIgnored) { pulse_reset(nullptr, {.low_ms = 1}); }
+
+TEST(PulseReset, LowThenHigh) {
+  RecordingPin pin;
+  pulse_reset(&pin, {.low_ms = 1});
+  EXPECT_EQ(pin.events, "SLH");
+}
+
+TEST(PulseReset, PreHighDrivesHighFirst) {
+  RecordingPin pin;
+  pulse_reset(&pin, {.high_before_ms = 1, .low_ms = 1, .high_after_ms = 1});
+  EXPECT_EQ(pin.events, "SHLH");
+}
+
+// Distinct waits, so dropping or swapping one shows up; only lower bounds, a busy host can run long
+TEST(PulseReset, HoldsEachLevelForItsTime) {
+  RecordingPin pin;
+  pulse_reset(&pin, {.high_before_ms = 10, .low_ms = 20, .high_after_ms = 30});
+  const uint32_t end = millis();
+  ASSERT_EQ(pin.events, "SHLH");
+  EXPECT_GE(pin.write_ms[1] - pin.write_ms[0], 10u);
+  EXPECT_GE(pin.write_ms[2] - pin.write_ms[1], 20u);
+  EXPECT_GE(end - pin.write_ms[2], 30u);
+}
+
+}  // namespace esphome::core::testing