From b41746cc54100fe1fef11eef452e4924568293c5 Mon Sep 17 00:00:00 2001
From: brisk <bskblake@gmail.com>
Date: Mon, 22 Jul 2024 22:32:28 +0930
Subject: [PATCH] pulse_counter_ulp: Use std::chrono instead of millis()

millis() appears to jump when a time component synchronises. steady_clock() should avoid this.
---
 .../pulse_counter_ulp/pulse_counter_ulp_sensor.cpp   | 12 ++++++------
 .../pulse_counter_ulp/pulse_counter_ulp_sensor.h     |  6 ++++--
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.cpp b/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.cpp
index cff57c5da9..c21f66b0f8 100644
--- a/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.cpp
+++ b/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.cpp
@@ -135,12 +135,12 @@ void PulseCounterUlpSensor::dump_config() {
 
 void PulseCounterUlpSensor::update() {
   UlpProgram::state raw = this->storage_.pop_state();
-  timestamp_t now;
-  timestamp_t interval;
-  now = millis();
-  interval = now - this->last_time_;
-  if (this->last_time_ != 0) {
-    float value = (60000.0f * raw.edge_count) / float(interval);  // per minute
+  clock::time_point now;
+  std::chrono::duration<float, std::ratio<60>> minutes;
+  now = clock::now();
+  minutes = now - this->last_time_;
+  if (this->last_time_ != clock::time_point{}) {
+    float value = raw.edge_count / minutes.count();  // pulses per minute
     ESP_LOGD(TAG, "'%s': Retrieved counter: %0.2f pulses/min", this->get_name().c_str(), value);
     this->publish_state(value);
   }
diff --git a/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.h b/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.h
index f4f96cf97b..e3c24154b4 100644
--- a/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.h
+++ b/esphome/components/pulse_counter_ulp/pulse_counter_ulp_sensor.h
@@ -5,13 +5,15 @@
 #include "esphome/components/sensor/sensor.h"
 
 #include <cinttypes>
+#include <chrono>
 
 namespace esphome {
 namespace pulse_counter_ulp {
 
 enum class CountMode { disable = 0, increment = 1, decrement = -1 };
 
-using timestamp_t = int64_t;
+// millis() jumps when a time component synchronises, so we use steady_clock instead
+using clock = std::chrono::steady_clock;
 
 struct UlpProgram {
   struct state {
@@ -47,7 +49,7 @@ class PulseCounterUlpSensor : public sensor::Sensor, public PollingComponent {
  protected:
   InternalGPIOPin *pin_;
   UlpProgram storage_;
-  timestamp_t last_time_{0};
+  clock::time_point last_time_{};
   uint32_t current_total_{0};
   sensor::Sensor *total_sensor_{nullptr};
 };