Fix portenta PDM.setBufferSize()

Author: pennam

libraries/PDM/src/PDM.h

@@ -40,6 +40,7 @@ class PDMClass
 
   void setGain(int gain);
   void setBufferSize(int bufferSize);
+  size_t getBufferSize();
 
 // private:
   void IrqHandler(bool halftranfer);

libraries/PDM/src/stm32/PDM.cpp

@@ -113,16 +113,21 @@ void PDMClass::setBufferSize(int bufferSize)
   _doubleBuffer.setSize(bufferSize);
 }
 
+size_t PDMClass::getBufferSize()
+{
+  return _doubleBuffer.getSize();
+}
+
 void PDMClass::IrqHandler(bool halftranfer)
 {
   if (_doubleBuffer.available() == 0) {
     g_pcmbuf = (uint16_t*)_doubleBuffer.data();
     audio_pendsv_callback();
     _doubleBuffer.swap(_doubleBuffer.availableForWrite());
-  }
 
-  if (_onReceive) {
+     if (_onReceive) {
       _onReceive();
+     }
   }
 }
 
@@ -135,6 +140,10 @@ void PDMIrqHandler(bool halftranfer)
 void PDMsetBufferSize(int size) {
   PDM.setBufferSize(size);
 }
+
+size_t PDMgetBufferSize() {
+  return PDM.getBufferSize();
+}
 }
 
 PDMClass PDM(0, 0, 0);

libraries/PDM/src/stm32/audio.c

@@ -303,8 +303,11 @@ int py_audio_init(size_t channels, uint32_t frequency, int gain_db, float highpa
         PDM_Filter_setConfig(&PDM_FilterHandler[i], &PDM_FilterConfig[i]);
     }
 
-    PDMsetBufferSize(samples_per_channel * g_o_channels * sizeof(int16_t));
-    //g_pcmbuf = malloc(samples_per_channel * g_channels * sizeof(int16_t));
+    uint32_t min_buff_size = samples_per_channel * g_o_channels * sizeof(int16_t);
+    uint32_t buff_size = PDMgetBufferSize();
+    if(buff_size < min_buff_size) {
+      PDMsetBufferSize(min_buff_size);
+    }
 
     return 1;
 }

libraries/PDM/src/utility/PDMDoubleBuffer.cpp

@@ -37,6 +37,11 @@ void PDMDoubleBuffer::setSize(int size)
   reset();
 }
 
+size_t PDMDoubleBuffer::getSize()
+{
+  return _size;
+}
+
 void PDMDoubleBuffer::reset()
 {
   _buffer[0] = (uint8_t*)realloc(_buffer[0], _size);

libraries/PDM/src/utility/PDMDoubleBuffer.h

@@ -31,6 +31,7 @@ class PDMDoubleBuffer
   virtual ~PDMDoubleBuffer();
 
   void setSize(int size);
+  size_t getSize();
 
   void reset();