From 72002ce70ecd3018d834abe6c9ed088dc295693b Mon Sep 17 00:00:00 2001
From: mknjc <markus.knetschke@gmail.com>
Date: Sun, 10 Jan 2021 20:05:53 +0100
Subject: [PATCH] Rotary Encoder: Don't call callbacks in the isr (#1456)

---
 .../rotary_encoder/rotary_encoder.cpp         | 51 ++++++++++++++++++-
 .../rotary_encoder/rotary_encoder.h           | 13 +++--
 2 files changed, 58 insertions(+), 6 deletions(-)

diff --git a/esphome/components/rotary_encoder/rotary_encoder.cpp b/esphome/components/rotary_encoder/rotary_encoder.cpp
index 873aaf1971..0398489dca 100644
--- a/esphome/components/rotary_encoder/rotary_encoder.cpp
+++ b/esphome/components/rotary_encoder/rotary_encoder.cpp
@@ -90,16 +90,34 @@ void ICACHE_RAM_ATTR HOT RotaryEncoderSensorStore::gpio_intr(RotaryEncoderSensor
   if (arg->pin_b->digital_read())
     input_state |= STATE_PIN_B_HIGH;
 
+  int8_t rotation_dir = 0;
   uint16_t new_state = STATE_LOOKUP_TABLE[input_state];
   if ((new_state & arg->resolution & STATE_HAS_INCREMENTED) != 0) {
     if (arg->counter < arg->max_value)
       arg->counter++;
-    arg->on_clockwise_callback_.call();
+    rotation_dir = 1;
   }
   if ((new_state & arg->resolution & STATE_HAS_DECREMENTED) != 0) {
     if (arg->counter > arg->min_value)
       arg->counter--;
-    arg->on_anticlockwise_callback_.call();
+    rotation_dir = -1;
+  }
+
+  if (rotation_dir != 0) {
+    auto first_zero = std::find(arg->rotation_events.begin(), arg->rotation_events.end(), 0);  // find first zero
+    if (first_zero == arg->rotation_events.begin()  // are we at the start (first event this loop iteration)
+        || std::signbit(*std::prev(first_zero)) !=
+               std::signbit(rotation_dir)  // or is the last stored event the wrong direction
+        || *std::prev(first_zero) == std::numeric_limits<int8_t>::lowest()  // or the last event slot is full (negative)
+        || *std::prev(first_zero) == std::numeric_limits<int8_t>::max()) {  // or the last event slot is full (positive)
+      if (first_zero != arg->rotation_events.end()) {                       // we have a free rotation slot
+        *first_zero += rotation_dir;                                        // store the rotation into a new slot
+      } else {
+        arg->rotation_events_overflow = true;
+      }
+    } else {
+      *std::prev(first_zero) += rotation_dir;  // store the rotation into the previous slot
+    }
   }
 
   arg->state = new_state;
@@ -137,6 +155,35 @@ void RotaryEncoderSensor::dump_config() {
   }
 }
 void RotaryEncoderSensor::loop() {
+  std::array<int8_t, 8> rotation_events;
+  bool rotation_events_overflow;
+  ets_intr_lock();
+  rotation_events = this->store_.rotation_events;
+  rotation_events_overflow = this->store_.rotation_events_overflow;
+
+  this->store_.rotation_events.fill(0);
+  this->store_.rotation_events_overflow = false;
+  ets_intr_unlock();
+
+  if (rotation_events_overflow) {
+    ESP_LOGW(TAG, "Captured more rotation events than expected");
+  }
+
+  for (auto events : rotation_events) {
+    if (events == 0)  // we are at the end of the recorded events
+      break;
+
+    if (events > 0) {
+      while (events--) {
+        this->on_clockwise_callback_.call();
+      }
+    } else {
+      while (events++) {
+        this->on_anticlockwise_callback_.call();
+      }
+    }
+  }
+
   if (this->pin_i_ != nullptr && this->pin_i_->digital_read()) {
     this->store_.counter = 0;
   }
diff --git a/esphome/components/rotary_encoder/rotary_encoder.h b/esphome/components/rotary_encoder/rotary_encoder.h
index e066188f22..000350d66c 100644
--- a/esphome/components/rotary_encoder/rotary_encoder.h
+++ b/esphome/components/rotary_encoder/rotary_encoder.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <array>
+
 #include "esphome/core/component.h"
 #include "esphome/core/esphal.h"
 #include "esphome/core/automation.h"
@@ -27,8 +29,8 @@ struct RotaryEncoderSensorStore {
   int32_t last_read{0};
   uint8_t state{0};
 
-  CallbackManager<void()> on_clockwise_callback_;
-  CallbackManager<void()> on_anticlockwise_callback_;
+  std::array<int8_t, 8> rotation_events{};
+  bool rotation_events_overflow{false};
 
   static void gpio_intr(RotaryEncoderSensorStore *arg);
 };
@@ -66,11 +68,11 @@ class RotaryEncoderSensor : public sensor::Sensor, public Component {
   float get_setup_priority() const override;
 
   void add_on_clockwise_callback(std::function<void()> callback) {
-    this->store_.on_clockwise_callback_.add(std::move(callback));
+    this->on_clockwise_callback_.add(std::move(callback));
   }
 
   void add_on_anticlockwise_callback(std::function<void()> callback) {
-    this->store_.on_anticlockwise_callback_.add(std::move(callback));
+    this->on_anticlockwise_callback_.add(std::move(callback));
   }
 
  protected:
@@ -79,6 +81,9 @@ class RotaryEncoderSensor : public sensor::Sensor, public Component {
   GPIOPin *pin_i_{nullptr};  /// Index pin, if this is not nullptr, the counter will reset to 0 once this pin is HIGH.
 
   RotaryEncoderSensorStore store_{};
+
+  CallbackManager<void()> on_clockwise_callback_;
+  CallbackManager<void()> on_anticlockwise_callback_;
 };
 
 template<typename... Ts> class RotaryEncoderSetValueAction : public Action<Ts...> {