Import Encoder library (#1769)

* Update encoder

- import modified Encoder library
- customize minimum delta value

* minimum delta in header config

* fixup! minimum delta in header config

* fix dead code, actually use interrupts

* move static class methods to normal funcs, apply namespace

* drop hardcoded register use

- use peripheral api (see cores/esp8266/esp8266_peri.h)
- remove bitmask and register struct members

* add a note about changes

* fixup! add a note about changes

code/espurna/config/general.h

@@ -335,6 +335,10 @@
 #define ENCODER_SUPPORT             0
 #endif
 
+#ifndef ENCODER_MINIMUM_DELTA
+#define ENCODER_MINIMUM_DELTA       1
+#endif
+
 //------------------------------------------------------------------------------
 // LED
 //------------------------------------------------------------------------------

code/espurna/config/hardware.h

@@ -3698,6 +3698,7 @@
     #define LIGHT_CHANNELS      1
     #define LIGHT_CH1_PIN       5
     #define LIGHT_CH1_INVERSE   0
+    #define ENCODER_SUPPORT     1
 
     // A bit of HLW8012 - pins 6,7,8
     #ifndef HLW8012_SUPPORT

code/espurna/encoder.ino

@@ -8,7 +8,7 @@ Copyright (C) 2018-2019 by Xose Pérez <xose dot perez at gmail dot com>
 
 #if ENCODER_SUPPORT && (LIGHT_PROVIDER != LIGHT_PROVIDER_NONE)
 
-#include <Encoder.h>
+#include "libs/Encoder.h"
 #include <vector>
 
 typedef struct {
@@ -22,6 +22,7 @@ typedef struct {
 } encoder_t;
 
 std::vector<encoder_t> _encoders;
+unsigned long _encoder_min_delta = 1;
 
 void _encoderConfigure() {
 
@@ -85,24 +86,22 @@ void _encoderConfigure() {
         }
     }
 
+    _encoder_min_delta = getSetting("encMinDelta", ENCODER_MINIMUM_DELTA).toInt();
+    if (!_encoder_min_delta) _encoder_min_delta = 1;
+
 }
 
 void _encoderLoop() {
 
-    // for each encoder
+    // for each encoder, read delta (read()) and map button action
     for (unsigned char i=0; i<_encoders.size(); i++) {
 
-        // get encoder
         encoder_t encoder = _encoders[i];
 
-        // read encoder
         long delta = encoder.encoder->read();
         encoder.encoder->write(0);
-        if (0 == delta) continue;
-
-        DEBUG_MSG_P(PSTR("[ENCODER] Delta: %d\n"), delta);
+        if ((0 == delta) || (_encoder_min_delta > abs(delta))) continue;
 
-        // action
         if (encoder.button_pin == GPIO_NONE) {
 
             // if there is no button, the encoder drives CHANNEL1
@@ -110,7 +109,7 @@ void _encoderLoop() {
 
         } else {
 
-            // check if button is pressed
+            // otherwise, use button based on encoder mode
             bool pressed = (digitalRead(encoder.button_pin) != encoder.button_logic);
 
             if (ENCODER_MODE_CHANNEL == encoder.mode) {

code/espurna/libs/Encoder.h

@@ -0,0 +1,228 @@
+/* ---------------------------- Original copyright -----------------------------
+ *
+ * Encoder Library, for measuring quadrature encoded signals
+ * http://www.pjrc.com/teensy/td_libs_Encoder.html
+ * Copyright (c) 2011,2013 PJRC.COM, LLC - Paul Stoffregen <paul@pjrc.com>
+ *
+ * Version 1.2 - fix -2 bug in C-only code
+ * Version 1.1 - expand to support boards with up to 60 interrupts
+ * Version 1.0 - initial release
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * Encoder.h, updated for ESP8266 use in ESPurna. Other hardware is not supported.
+ *
+ * - Added ESP-specific attributes to ISR handlers to place them in IRAM.
+ * - Reduced per-encoder structure sizes - only 5 Encoders can be used on ESP8266,
+ *   and we can directly reference pin number instead of storing both register and bitmask
+ *
+ */
+
+#pragma once
+
+//                           _______         _______       
+//               Pin1 ______|       |_______|       |______ Pin1
+// negative <---         _______         _______         __      --> positive
+//               Pin2 __|       |_______|       |_______|   Pin2
+
+// new new old old
+// pin2 pin1 pin2 pin1 Result
+// ---- ---- ---- ---- ------
+// 0    0    0    0    no movement
+// 0    0    0    1    +1
+// 0    0    1    0    -1
+// 0    0    1    1    +2  (assume pin1 edges only)
+// 0    1    0    0    -1
+// 0    1    0    1    no movement
+// 0    1    1    0    -2  (assume pin1 edges only)
+// 0    1    1    1    +1
+// 1    0    0    0    +1
+// 1    0    0    1    -2  (assume pin1 edges only)
+// 1    0    1    0    no movement
+// 1    0    1    1    -1
+// 1    1    0    0    +2  (assume pin1 edges only)
+// 1    1    0    1    -1
+// 1    1    1    0    +1
+// 1    1    1    1    no movement
+
+namespace EncoderLibrary {
+
+    typedef struct {
+        uint8_t             pin1;
+        uint8_t             pin2;
+        uint8_t             state;
+        int32_t             position;
+    } encoder_values_t;
+
+    constexpr const unsigned char ENCODERS_MAXIMUM {5u};
+
+    encoder_values_t * EncoderValues[ENCODERS_MAXIMUM] = {nullptr};
+
+    uint8_t _encoderFindStorage() {
+        for (uint8_t i = 0; i < ENCODERS_MAXIMUM; i++) {
+            if (EncoderValues[i] == nullptr) {
+                return i;
+            }
+        }
+        return ENCODERS_MAXIMUM;
+    }
+
+    void _encoderCleanStorage(uint8_t pin1, uint8_t pin2) {
+        for (uint8_t i = 0; i < ENCODERS_MAXIMUM; i++) {
+            if (EncoderValues[i] == nullptr) continue;
+            if (((EncoderValues[i])->pin1 == pin1) && ((EncoderValues[i])->pin2 == pin2)) {
+                EncoderValues[i] = nullptr;
+                break;
+            }
+        }
+    }
+
+    // update() is not meant to be called from outside Encoder,
+    // but it is public to allow static interrupt routines.
+    void ICACHE_RAM_ATTR update(encoder_values_t *target) {
+        uint8_t p1val = GPIP(target->pin1);
+        uint8_t p2val = GPIP(target->pin2);
+        uint8_t state = target->state & 3;
+        if (p1val) state |= 4;
+        if (p2val) state |= 8;
+        target->state = (state >> 2);
+        switch (state) {
+            case 1: case 7: case 8: case 14:
+                target->position++;
+                return;
+            case 2: case 4: case 11: case 13:
+                target->position--;
+                return;
+            case 3: case 12:
+                target->position += 2;
+                return;
+            case 6: case 9:
+                target->position -= 2;
+                return;
+        }
+    }
+
+    // 2 pins per encoder, 1 isr per encoder
+    void ICACHE_RAM_ATTR isr0() { update(EncoderValues[0]); }
+    void ICACHE_RAM_ATTR isr1() { update(EncoderValues[1]); }
+    void ICACHE_RAM_ATTR isr2() { update(EncoderValues[2]); }
+    void ICACHE_RAM_ATTR isr3() { update(EncoderValues[3]); }
+    void ICACHE_RAM_ATTR isr4() { update(EncoderValues[4]); }
+
+    constexpr void (*_isr_funcs[5])() = {
+        isr0, isr1, isr2, isr3, isr4
+    };
+
+    class Encoder {
+
+    private:
+
+        encoder_values_t values;
+
+    public:
+
+        Encoder(uint8_t pin1, uint8_t pin2) {
+
+            values.pin1 = pin1;
+            values.pin2 = pin2;
+
+            pinMode(values.pin1, INPUT_PULLUP);
+            pinMode(values.pin2, INPUT_PULLUP);
+
+            values.position = 0;
+
+            // allow time for a passive R-C filter to charge
+            // through the pullup resistors, before reading
+            // the initial state
+            delayMicroseconds(2000);
+
+            uint8_t current = 0;
+            if (GPIP(values.pin1)) {
+                current |= 1;
+            }
+
+            if (GPIP(values.pin2)) {
+                current |= 2;
+            }
+
+            values.state = current;
+
+            attach();
+
+        }
+
+        ~Encoder() {
+            detach();
+        }
+
+        uint8_t pin1() {
+            return values.pin1;
+        }
+
+        uint8_t pin2() {
+            return values.pin2;
+        }
+
+        int32_t read() {
+            noInterrupts();
+
+            update(&values);
+            int32_t ret = values.position;
+
+            interrupts();
+            return ret;
+        }
+
+        void write(int32_t position) {
+            noInterrupts();
+            values.position = position;
+            interrupts();
+        }
+
+        bool attach() {
+            uint8_t index = _encoderFindStorage();
+            if (index >= ENCODERS_MAXIMUM) return false;
+
+            EncoderValues[index] = &values;
+
+            attachInterrupt(values.pin1, _isr_funcs[index], CHANGE);
+            attachInterrupt(values.pin2, _isr_funcs[index], CHANGE);
+
+            return true;
+        }
+
+        void detach() {
+            noInterrupts();
+
+            _encoderCleanStorage(values.pin1, values.pin2);
+
+            detachInterrupt(values.pin1);
+            detachInterrupt(values.pin2);
+
+            interrupts();
+        }
+
+
+    };
+
+}
+
+using EncoderLibrary::Encoder;

code/platformio.ini

@@ -86,7 +86,6 @@ lib_deps =
     https://github.com/xoseperez/debounceevent.git#2.0.5
     https://github.com/xoseperez/eeprom_rotate#0.9.2
     Embedis
-    Encoder
     https://github.com/plerup/espsoftwareserial#3.4.1
     https://github.com/me-no-dev/ESPAsyncTCP#55cd520
     https://github.com/me-no-dev/ESPAsyncWebServer#05306e4