Making LPCD compatible with port-expander + removing race-condition

src/Port.cpp

@@ -246,10 +246,13 @@ void Port_Write(const uint8_t _channel, const bool _newState) {
         // If interrupt-handling is active, only ready port-expander's register if interrupt was fired
         #ifdef PE_INTERRUPT_PIN_ENABLE
             if (!Port_AllowReadFromPortExpander && !Port_AllowInitReadFromPortExpander) {
+                //Serial.println("Interrupt false!");
                 return;
-            } else {
-                Port_AllowReadFromPortExpander = false;
+            } else if (Port_AllowInitReadFromPortExpander) {
                 Port_AllowInitReadFromPortExpander = false;
+            } else if (Port_AllowReadFromPortExpander || Port_AllowInitReadFromPortExpander) {
+                //Serial.println("Interrupt true!");
+                Port_AllowReadFromPortExpander = false;
             }
         #endif
 
@@ -265,6 +268,20 @@ void Port_Write(const uint8_t _channel, const bool _newState) {
         }
     }
 
+    // Make sure ports are read finally at shutdown in order to clear any active IRQs that could cause re-wakeup immediately
+    void Port_Exit(void) {
+        i2cBusTwo.beginTransmission(expanderI2cAddress);
+        for (uint8_t i = 0; i < 2; i++) {
+            i2cBusTwo.write(0x00 + i);                      // Pointer to input-register...
+            i2cBusTwo.endTransmission();
+            i2cBusTwo.requestFrom(expanderI2cAddress, 1u);   // ...and read its byte
+
+            if (i2cBusTwo.available()) {
+                Port_ExpanderPortsInputChannelStatus[i] = i2cBusTwo.read();
+            }
+        }
+    }
+
     // Tests if port-expander can be detected at address configured
     void Port_Test(void) {
         i2cBusTwo.beginTransmission(expanderI2cAddress);

src/Port.h

@@ -6,3 +6,4 @@ bool Port_Read(const uint8_t _channel);
 void Port_Write(const uint8_t _channel, const bool _newState, const bool _initGpio);
 void Port_Write(const uint8_t _channel, const bool _newState);
 bool Port_Detect_Mode_HP(bool _state);
+void Port_Exit(void);

src/RfidPn5180.cpp

@@ -34,6 +34,20 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
 
 #ifdef RFID_READER_TYPE_PN5180
     static void Rfid_Task(void *parameter);
+    static TaskHandle_t rfidTaskHandle;
+
+    #ifdef PN5180_ENABLE_LPCD
+        void Rfid_EnableLpcd(void);
+        bool enabledLpcdShutdown = false;       // Indicates if LPCD should be activated as part of the shutdown-process
+
+        void Rfid_SetLpcdShutdownStatus(bool lpcdStatus) {
+            enabledLpcdShutdown = lpcdStatus;
+        }
+
+        bool Rfid_GetLpcdShutdownStatus(void) {
+            return enabledLpcdShutdown;
+        }
+    #endif
 
     void Rfid_Init(void) {
         #ifdef PN5180_ENABLE_LPCD
@@ -41,7 +55,9 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
             gpio_deep_sleep_hold_dis();
             gpio_hold_dis(gpio_num_t(RFID_CS));  // NSS
             gpio_hold_dis(gpio_num_t(RFID_RST)); // RST
-            pinMode(RFID_IRQ, INPUT);
+            #if (RFID_IRQ >= 0 && RFID_IRQ <= 39)
+                pinMode(RFID_IRQ, INPUT);       // Not necessary for port-expander as for pca9555 all pins are configured as input per default
+            #endif
         #endif
 
         xTaskCreatePinnedToCore(
@@ -50,7 +66,7 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
             1536,                   /* Stack size in words */
             NULL,                   /* Task input parameter */
             2 | portPRIVILEGE_BIT,  /* Priority of the task */
-            NULL,                   /* Task handle. */
+            &rfidTaskHandle,        /* Task handle. */
             0                       /* Core where the task should run */
         );
     }
@@ -75,6 +91,15 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
 
         for (;;) {
             vTaskDelay(portTICK_RATE_MS * 10u);
+            #ifdef PN5180_ENABLE_LPCD
+                if (Rfid_GetLpcdShutdownStatus()) {
+                    Rfid_EnableLpcd();
+                    Rfid_SetLpcdShutdownStatus(false);          // give feedback that execution is complete
+                    while (true) {
+                        vTaskDelay(portTICK_RATE_MS * 100u);    // there's no way back if shutdown was initiated
+                    }
+                }
+            #endif
             String cardIdString;
             bool cardReceived = false;
             #ifdef PAUSE_WHEN_RFID_REMOVED
@@ -245,6 +270,17 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
     }
 
     void Rfid_Exit(void) {
+        #ifdef PN5180_ENABLE_LPCD
+            Rfid_SetLpcdShutdownStatus(true);
+            while (Rfid_GetLpcdShutdownStatus()) {          // Make sure init of LPCD is complete!
+                vTaskDelay(portTICK_RATE_MS * 10u);
+            }
+        #endif
+        vTaskDelete(rfidTaskHandle);
+    }
+
+    // Handles activation of LPCD (while shutdown is in progress)
+    void Rfid_EnableLpcd(void) {
         // goto low power card detection mode
         #ifdef PN5180_ENABLE_LPCD
             static PN5180 nfc(RFID_CS, RFID_BUSY, RFID_RST);
@@ -263,8 +299,12 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
                 return;
             }
             Serial.println(F("prepare low power card detection..."));
+            uint8_t irqConfig = 0b0000010; // Set IRQ active low + clear IRQ-register
+            nfc.writeEEprom(IRQ_PIN_CONFIG, &irqConfig, 1);
+            /*nfc.readEEprom(IRQ_PIN_CONFIG, &irqConfig, 1);
+            Serial.print(F("IRQ_PIN_CONFIG=0x"));
+            Serial.println(irqConfig, HEX);*/
             nfc.prepareLPCD();
-            nfc.clearIRQStatus(0xffffffff);
             Serial.print(F("PN5180 IRQ PIN: "));
             Serial.println(Port_Read(RFID_IRQ));
             // turn on LPCD
@@ -272,7 +312,9 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
             if (nfc.switchToLPCD(wakeupCounterInMs)) {
                 Serial.println(F("switch to low power card detection: success"));
                 // configure wakeup pin for deep-sleep wake-up, use ext1
+                #if (RFID_IRQ >= 0 && RFID_IRQ <= 39)
                     esp_sleep_enable_ext1_wakeup((1ULL << (RFID_IRQ)), ESP_EXT1_WAKEUP_ANY_HIGH);
+                #endif
                 // freeze pin states in deep sleep
                 gpio_hold_en(gpio_num_t(RFID_CS));  // CS/NSS
                 gpio_hold_en(gpio_num_t(RFID_RST)); // RST
@@ -299,7 +341,9 @@ extern unsigned long Rfid_LastRfidCheckTimestamp;
                 if (nfc14443.switchToLPCD(wakeupCounterInMs)) {
                     Log_Println((char *) FPSTR(lowPowerCardSuccess), LOGLEVEL_INFO);
                     // configure wakeup pin for deep-sleep wake-up, use ext1
+                    #if (RFID_IRQ >= 0 && RFID_IRQ <= 39)
                         esp_sleep_enable_ext1_wakeup((1ULL << (RFID_IRQ)), ESP_EXT1_WAKEUP_ANY_HIGH);
+                    #endif
                     // freeze pin states in deep sleep
                     gpio_hold_en(gpio_num_t(RFID_CS));  // CS/NSS
                     gpio_hold_en(gpio_num_t(RFID_RST)); // RST

src/System.cpp

@@ -214,6 +214,7 @@ void System_DeepSleepManager(void) {
         digitalWrite(POWER, LOW);
         delay(200);
         Rfid_Exit();
+        Port_Exit();
         Serial.println(F("deep-sleep, good night......."));
         esp_deep_sleep_start();
     }

src/main.cpp

@@ -132,6 +132,7 @@ void setup() {
         Rfid_Init();
     #endif
     // Check if wakeup-reason was card-detection (PN5180 only)
+    // This only works if RFID.IRQ is connected to a GPIO and not to a port-expander
     esp_sleep_wakeup_cause_t wakeup_reason = esp_sleep_get_wakeup_cause();
     if (wakeup_reason == ESP_SLEEP_WAKEUP_EXT1) {
         Rfid_WakeupCheck();

src/revision.h

@@ -1,4 +1,4 @@
 #ifndef __REVISION_H__
     #define __REVISION_H__
-    constexpr const char softwareRevision[] PROGMEM = "Software-revision: 20211007-1";
+    constexpr const char softwareRevision[] PROGMEM = "Software-revision: 20211014-1";
 #endif