Pin manager support for sharing multipin buses.

wled00/pin_manager.cpp

@@ -1,6 +1,7 @@
 #include "pin_manager.h"
 #include "wled.h"
 
+#ifdef WLED_DEBUG
 static void DebugPrintOwnerTag(PinOwner tag)
 {
   uint32_t q = static_cast<uint8_t>(tag);
@@ -10,6 +11,7 @@ static void DebugPrintOwnerTag(PinOwner tag)
     DEBUG_PRINT(F("(no owner)"));
   }
 }
+#endif
 
 /// Actual allocation/deallocation routines
 bool PinManagerClass::deallocatePin(byte gpio, PinOwner tag)
@@ -19,12 +21,14 @@ bool PinManagerClass::deallocatePin(byte gpio, PinOwner tag)
 
   // if a non-zero ownerTag, only allow de-allocation if the owner's tag is provided
   if ((ownerTag[gpio] != PinOwner::None) && (ownerTag[gpio] != tag)) {
+    #ifdef WLED_DEBUG
     DEBUG_PRINT(F("PIN DEALLOC: IO "));
     DEBUG_PRINT(gpio);
     DEBUG_PRINT(F(" allocated by "));
     DebugPrintOwnerTag(ownerTag[gpio]);
     DEBUG_PRINT(F(", but attempted de-allocation by "));
     DebugPrintOwnerTag(tag);
+    #endif
     return false;
   }
   
@@ -34,6 +38,49 @@ bool PinManagerClass::deallocatePin(byte gpio, PinOwner tag)
   ownerTag[gpio] = PinOwner::None;
   return true;
 }
+
+// support function for deallocating multiple pins
+bool PinManagerClass::deallocateMultiplePins(const uint8_t *pinArray, byte arrayElementCount, PinOwner tag)
+{
+  bool shouldFail = false;
+  DEBUG_PRINTLN(F("MULTIPIN DEALLOC"));
+  // first verify the pins are OK and allocated by selected owner
+  for (int i = 0; i < arrayElementCount; i++) {
+    byte gpio = pinArray[i];
+    if (gpio == 0xFF) {
+      // explicit support for io -1 as a no-op (no allocation of pin),
+      // as this can greatly simplify configuration arrays
+      continue;
+    }
+    if (isPinAllocated(gpio, tag)) {
+      // if the current pin is allocated by selected owner it is possible to release it
+      continue;
+    }
+    #ifdef WLED_DEBUG
+    DEBUG_PRINT(F("PIN DEALLOC: IO "));
+    DEBUG_PRINT(gpio);
+    DEBUG_PRINT(F(" allocated by "));
+    DebugPrintOwnerTag(ownerTag[gpio]);
+    DEBUG_PRINT(F(", but attempted de-allocation by "));
+    DebugPrintOwnerTag(tag);
+    #endif
+    shouldFail = true;
+  }
+  if (shouldFail) {
+    return false; // no pins deallocated
+  }
+  if (tag==PinOwner::HW_I2C) {
+    if (i2cAllocCount && --i2cAllocCount>0) {
+      // no deallocation done until last owner releases pins
+      return true;
+    }
+  }
+  for (int i = 0; i < arrayElementCount; i++) {
+    deallocatePin(pinArray[i], tag);
+  }
+  return true;
+}
+
 bool PinManagerClass::allocateMultiplePins(const managed_pin_type * mptArray, byte arrayElementCount, PinOwner tag)
 {
   bool shouldFail = false;
@@ -46,17 +93,24 @@ bool PinManagerClass::allocateMultiplePins(const managed_pin_type * mptArray, by
       continue;
     }
     if (!isPinOk(gpio, mptArray[i].isOutput)) {
+      #ifdef WLED_DEBUG
       DEBUG_PRINT(F("PIN ALLOC: Invalid pin attempted to be allocated: "));
       DEBUG_PRINT(gpio);
       DEBUG_PRINTLN(F(""));
+      #endif
       shouldFail = true;
     }
-    if (isPinAllocated(gpio)) {
+    if (tag==PinOwner::HW_I2C && isPinAllocated(gpio, tag)) {
+      // allow multiple "allocations" of HW I2C bus pins
+      continue;
+    } else if (isPinAllocated(gpio)) {
+      #ifdef WLED_DEBUG
       DEBUG_PRINT(F("PIN ALLOC: FAIL: IO ")); 
       DEBUG_PRINT(gpio);
       DEBUG_PRINT(F(" already allocated by "));
       DebugPrintOwnerTag(ownerTag[gpio]);
       DEBUG_PRINTLN(F(""));
+      #endif
       shouldFail = true;
     }
   }
@@ -64,6 +118,8 @@ bool PinManagerClass::allocateMultiplePins(const managed_pin_type * mptArray, by
     return false;
   }
 
+  if (tag==PinOwner::HW_I2C) i2cAllocCount++;
+
   // all pins are available .. track each one
   for (int i = 0; i < arrayElementCount; i++) {
     byte gpio = mptArray[i].pin;
@@ -79,15 +135,19 @@ bool PinManagerClass::allocateMultiplePins(const managed_pin_type * mptArray, by
   }
   return true;
 }
+
 bool PinManagerClass::allocatePin(byte gpio, bool output, PinOwner tag)
 {
-  if (!isPinOk(gpio, output)) return false;
+  // HW I2C pins have to be allocated using allocateMultiplePins variant since there is always SCL/SDA pair
+  if (!isPinOk(gpio, output) || tag==PinOwner::HW_I2C) return false;
   if (isPinAllocated(gpio)) {
+    #ifdef WLED_DEBUG
     DEBUG_PRINT(F("PIN ALLOC: Pin ")); 
     DEBUG_PRINT(gpio);
     DEBUG_PRINT(F(" already allocated by "));
     DebugPrintOwnerTag(ownerTag[gpio]);
     DEBUG_PRINTLN(F(""));
+    #endif
     return false;
   }
 
@@ -106,7 +166,7 @@ bool PinManagerClass::isPinAllocated(byte gpio, PinOwner tag)
   if (!isPinOk(gpio, false)) return true;
   if ((tag != PinOwner::None) && (ownerTag[gpio] != tag)) return false;
   byte by = gpio >> 3;
-  byte bi = gpio - 8*by;
+  byte bi = gpio - (by<<3);
   return bitRead(pinAlloc[by], bi);
 }