From 465a17789d6a2a98e86e2263b72a3e2329e27f67 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Hru=C5=A1ka?= <ondra@ondrovo.com>
Date: Fri, 3 Jan 2020 19:28:57 +0100
Subject: [PATCH] remove gpio isr, polling debouncer works better

---
 main/knob.c | 356 ++++++++--------------------------------------------
 1 file changed, 55 insertions(+), 301 deletions(-)

diff --git a/main/knob.c b/main/knob.c
index d8efa29..18fe32e 100644
--- a/main/knob.c
+++ b/main/knob.c
@@ -8,347 +8,101 @@ const int pushPin = 5;
 const int wheelPin1 = 18;
 const int wheelPin2 = 23;
 
-//const int sigPin1 = 12;
-//const int sigPin2 = 14;
-
 #define DEBOUNCE_WHEEL_MS 3
 #define DEBOUNCE_BTN_MS 10
 
-static void handle_pushbtn(void *arg);
-static void handle_wheel(void *arg);
-
-
-
 static void debounce_service(void *arg);
 static TaskHandle_t hDebouncer;
 
 void knob_init() {
     printf("Knob init\n");
 
-//    gpio_config_t cfgWheel = {
-//        .pin_bit_mask = (1 << wheelPin1) /*| (1 << wheelPin2)*/,
-//        .mode = GPIO_MODE_INPUT,
-//        .pull_up_en = 1,
-//        .intr_type = GPIO_INTR_NEGEDGE, // neg means active
-//    };
-//    gpio_config(&cfgWheel);
-
     gpio_config_t cfgPush = {
-        .pin_bit_mask = (1 << pushPin) | (1 << wheelPin1),
+        .pin_bit_mask = (1 << pushPin) | (1 << wheelPin1) | (1 << wheelPin2),
         .mode = GPIO_MODE_INPUT,
-        .pull_up_en = 1,
-        .intr_type = GPIO_INTR_ANYEDGE, // neg means active
+        .pull_up_en = 1
     };
     gpio_config(&cfgPush);
 
-    // wheel2 without itr
-    cfgPush.intr_type = GPIO_INTR_DISABLE;
-    cfgPush.pin_bit_mask = (1 << wheelPin2);
-    gpio_config(&cfgPush);
-
-//    gpio_config_t output = {
-//        .pin_bit_mask = (1<<sigPin1)|(1<<sigPin2),
-//        .mode = GPIO_MODE_OUTPUT
-//    };
-//    gpio_config(&output);
-
-    gpio_install_isr_service(0);
-    gpio_intr_enable(pushPin);
-    gpio_intr_enable(wheelPin1);
-//    gpio_intr_enable(wheelPin2);
-
-    gpio_isr_handler_add(pushPin, handle_pushbtn, (void *)0);
-    gpio_isr_handler_add(wheelPin1, handle_wheel, (void *)0);
-    //gpio_isr_handler_add(wheelPin2, handle_wheel, (void *)1);
-
-
-    int rv = xTaskCreate(debounce_service, "debo", 2048, NULL, 6, &hDebouncer);
+    int rv = xTaskCreate(debounce_service, "debo", 4096, NULL, 6, &hDebouncer);
     assert (rv == pdPASS);
 }
 
-#if 0
-enum state {
-    S_11 = 0,
-
-    S_FWD_1_01 = 1,
-    S_FWD_2_00 = 2,
-    S_FWD_3_10 = 3,
-
-    S_BCK_1_10 = 4,
-    S_BCK_2_00 = 5,
-    S_BCK_3_01 = 6,
-
-    S_ILLEGAL  = 7,
-};
-
-#define SW_FWD 0b10000000
-#define SW_BCK 0b01000000
-
-static enum state wheelState = S_11;
-
-const uint8_t switch_table[28] = {
-    /* -- S_11 -- */
-    S_ILLEGAL, /* 00 ILLEGAL */
-    S_FWD_1_01, /* 01 ADVANCE */
-    S_BCK_1_10, /* 10 BACK */
-    S_11, /* 11 */
-
-    /* -- S_FWD_1_01 -- */
-    S_FWD_2_00, /* 00 ADVANCE */
-    S_FWD_1_01, /* 01 */
-    S_FWD_3_10,  /* 10 ILLEGAL */
-    S_11,       /* 11 ABORT */
-
-    /* -- S_FWD_2_00 -- */
-    S_FWD_2_00, /* 00 */
-    S_FWD_1_01, /* 01 ABORT */
-    S_FWD_3_10, /* 10 ADVANCE */
-    S_ILLEGAL,  /* 11 ILLEGAL */
-
-    /* -- S_FWD_3_10 -- */
-    S_FWD_2_00, /* 00 ABORT */
-    S_FWD_1_01,  /* 01 ILLEGAL */
-    S_FWD_3_10, /* 10 */
-    SW_FWD | S_11, /* 11 ADVANCE */
-
-    /* -- S_BCK_1_10 -- */
-    S_BCK_2_00, /* 00 ADVANCE */
-    S_BCK_3_01, /* 01 ILLEGAL */
-    S_BCK_1_10, /* 10 */
-    S_11,       /* 11 ABORT */
-
-    /* -- S_BCK_2_00 -- */
-    S_BCK_2_00, /* 00 */
-    S_BCK_3_01, /* 01 */
-    S_BCK_1_10, /* 10 ABORT */
-    S_ILLEGAL, /* 11 */
-
-    /* -- S_BCK_3_01 -- */
-    S_BCK_2_00, /* 00 */
-    S_BCK_3_01, /* 01 */
-    S_BCK_1_10, /* 10 */
-    SW_BCK | S_11, /* 11 */
-};
-
-static uint8_t OldEnc = 0b00;
-#endif
-
-static void handle_wheel(void *arg) {
-    static uint32_t negedge_time = 0;
-    static uint32_t posedge_time = 0;
-    static bool last_edge_level = 1;
-    static bool flipflop = 0;
-
-    const uint32_t inputs = gpio_input_get();
-    const bool a = 0 != (inputs & (1 << wheelPin1)); // neg = active
-    const bool b = 0 != (inputs & (1 << wheelPin2));
-
-    // This discards "false rising edge" when we get triggered by a rising edge
-    //
-    if (a == last_edge_level) {
-        return;
-    }
-    last_edge_level = a;
-
-    const uint32_t time = xTaskGetTickCount();
+static void __attribute__((noreturn)) debounce_service(void *arg) {
+    struct debo {
+        bool state;
+        uint32_t start_time;
+        uint32_t debo_time;
+    };
 
-    flipflop ^= 1;
-//    gpio_set_level(sigPin2, flipflop);
+    struct debo state[3] = {
+        {.debo_time = pdMS_TO_TICKS(DEBOUNCE_BTN_MS)},   // push
+        {.debo_time = pdMS_TO_TICKS(DEBOUNCE_WHEEL_MS)}, // wheel input 1
+        {.debo_time = pdMS_TO_TICKS(DEBOUNCE_WHEEL_MS)}  // wheel input 2
+    };
 
-    int dir = 0;
-    if (!a) {
-        if ((time - posedge_time) > pdMS_TO_TICKS(DEBOUNCE_WHEEL_MS)) {
-            // negedge
-            negedge_time = time;
-//            gpio_set_level(sigPin1, 0);
-        }
-    } else {
-        // posedge
-        if ((time - negedge_time) > pdMS_TO_TICKS(DEBOUNCE_WHEEL_MS)) {
-            posedge_time = time;
-            if (b) {
-                dir = -1;
-            } else {
-                dir = 1;
-            }
-//            gpio_set_level(sigPin1, 1);
-        }
-    }
+    while (1) {
+        vTaskDelay(pdMS_TO_TICKS(1));
 
-#if 0
-    const uint32_t inputs = gpio_input_get();
-    bool a = 0 == (inputs & (1 << wheelPin1)); // neg = active
-    bool b = 0 == (inputs & (1 << wheelPin2));
+        uint32_t now = xTaskGetTickCount();
 
-#define ENCODER_POS1 1
-#define ENCODER_POS2 2
-#define ENCODER_POS3 3
-#define ENCODER_POS0 0
+        const uint32_t inputs = gpio_input_get();
 
-    uint8_t NewEnc = a | (b<<1);
-    if (NewEnc ^ OldEnc) { // Encoder value changed???
-        switch(NewEnc) {
-            case ENCODER_POS1 : // 01
-                if (OldEnc == ENCODER_POS0) // 00
-                    dir--;
-                else
-                    dir++;
-                break;
-            case ENCODER_POS3 : // 11
-                if (OldEnc == ENCODER_POS1) // 01
-                    dir--;
-                else
-                    dir++;
-                break;
-            case ENCODER_POS2 : // 10
-                if (OldEnc == ENCODER_POS3) // 11
-                    dir--;
-                else
-                    dir++;
-                break;
-            case ENCODER_POS0 : // 00
-                if (OldEnc == ENCODER_POS2) // 10
-                    dir--;
-                else
-                    dir++;
-                break;
+        bool input[3] = {
+            (inputs & (1 << pushPin)) == 0,
+            (inputs & (1 << wheelPin1)) != 0,
+            (inputs & (1 << wheelPin2)) != 0,
         };
-        OldEnc = NewEnc;
-    }; // end if encoder value changed.
-#endif
 
-#if 0
-    // Omron version
-    int which = (int)arg;
+        enum change {
+            CHG_NONE = 2,
+            CHG_SET = 1,
+            CHG_CLEAR = 0,
+        };
 
-    const uint32_t inputs = gpio_input_get();
+        enum change changes[3] = {CHG_NONE, CHG_NONE, CHG_NONE};
 
-    bool a = 0 == (inputs & (1 << wheelPin1)); // neg = active
-    bool b = 0 == (inputs & (1 << wheelPin2));
+        for (int i=0; i<3;i++) {
+            if (input[i] == !state[i].state) {
+                // Change detected
+                if (state[i].start_time == 0) {
+                    // start counting
+                    state[i].start_time = now;
+                }
 
-    if (which == 0) { // itr from A
-        if (a) {
-            if (b) {
-                dir = -1;
+                if ((state[i].start_time != 0) && (now - state[i].start_time > state[i].debo_time)) {
+                    state[i].state = !state[i].state;
+                    changes[i] = state[i].state ? CHG_SET : CHG_CLEAR;
+                }
             }
             else {
-                dir = 1;
+                // returned back to original, reset counter
+                state[i].start_time = 0;
             }
         }
-    }
-    else { // itr from B
-        if (b) {
-            if (a) {
-                dir = 1;
+
+        uint32_t signal = 0;
+
+        // Wheel logic
+        if (changes[1] == CHG_SET) {
+            if (state[2].state) {
+                signal |= 0b01;
             }
             else {
-                dir = -1;
+                signal |= 0b10;
             }
         }
-    }
-#endif
-
-#if 0
-    // Naive version
-    int which = arg;
-
-    const uint32_t inputs = gpio_input_get();
-
-    bool a = 0 == (inputs & (1 << wheelPin1)); // neg = active
-    bool b = 0 == (inputs & (1 << wheelPin2));
 
-    if (which == 0) { // itr from A
-        if (b) {
-            dir = -1;
-        } /*else {
-            dir = 1;
-        }*/
-    }
-    else { // itr from B
-        if (a) {
-            dir = 1;
-        } /*else {
-            dir = -1;
-        }*/
-    }
-#endif
-
-#if 0
-    // More complex version
-    const uint32_t inputs = gpio_input_get();
-    const uint8_t ab =
-        (((inputs >> wheelPin2) & 1) << 1) |
-        ((inputs >> wheelPin1) & 1);
-
-    if (wheelState == S_ILLEGAL) {
-        if (ab != 0b11) {
-            return;
+        // knob
+        if (changes[0] != CHG_NONE) {
+            signal |= 0b100 << changes[0];
         }
-    }
 
-    uint8_t next = switch_table[wheelState*4 + ab];
-
-    if (next & SW_FWD) dir = 1;
-    if (next & SW_BCK) dir = -1;
-    next &= ~(SW_FWD | SW_BCK);
-
-    wheelState = next;
-#endif
-
-    if (dir != 0) {
-        BaseType_t higherWoken = 0;
-        xTaskNotifyFromISR(hGuiThread, dir == 1 ? 0b10 : 0b01, eSetBits, &higherWoken);
-        if (higherWoken) portYIELD_FROM_ISR();
-    }
-}
-
-static void __attribute__((noreturn)) debounce_service(void *arg) {
-    bool push_state = 0;
-    uint32_t push_change_time = 0;
-
-    while (1) {
-//        uint32_t value = 0;
-//        xTaskNotifyWait(0, ULONG_MAX, &value, pdMS_TO_TICKS(1));
-        vTaskDelay(pdMS_TO_TICKS(1));
-
-        uint32_t now = xTaskGetTickCount();
-
-        const uint32_t inputs = gpio_input_get();
-        bool pushed = (inputs & (1 << pushPin)) == 0;
-
-        if (pushed) { // event "PUSHED"
-            if (!push_state) {
-                if (push_change_time == 0) {
-                    push_change_time = now;
-                }
-            } else {
-                push_change_time = 0;
-            }
-        }
-        else { // event "RELEASED"
-            if (push_state) {
-                if (push_change_time == 0) {
-                    push_change_time = now;
-                }
-            } else {
-                push_change_time = 0;
-            }
-        }
-
-        if ((push_change_time != 0) && (now - push_change_time > pdMS_TO_TICKS(DEBOUNCE_BTN_MS))) {
-            push_state = !push_state;
+        // send event to GUI
+        if (signal != 0) {
             BaseType_t higherWoken = 0;
-            xTaskNotifyFromISR(hGuiThread, 0b100<<push_state, eSetBits, &higherWoken);
+            xTaskNotifyFromISR(hGuiThread, signal, eSetBits, &higherWoken);
             if (higherWoken) portYIELD_FROM_ISR();
         }
     }
 }
-
-static void handle_pushbtn(void *arg) {
-//    const uint32_t inputs = gpio_input_get();
-//    bool pushed = (inputs & (1 << pushPin)) == 0;
-//
-//    BaseType_t higherWoken = 0;
-//    xTaskNotifyFromISR(hDebouncer, 1<<pushed, eSetBits, &higherWoken);
-//    if (higherWoken) portYIELD_FROM_ISR();
-}