Esp32 i2s cleanup (#521)

* ESP32 I2s deallocation

* NULL pointers

src/internal/DotStarEsp32DmaSpiMethod.h

@@ -127,7 +127,7 @@ public:
             ESP_ERROR_CHECK(ret);            
         }
         free(_data);
-        free(_dmadata);
+        heap_caps_free(_dmadata);
         _spiHandle = NULL;
     }
 

src/internal/Esp32_i2s.c

@@ -126,6 +126,7 @@ static i2s_bus_t I2S[I2S_NUM_MAX] = {
 
 void IRAM_ATTR i2sDmaISR(void* arg);
 
+
 bool i2sInitDmaItems(uint8_t bus_num) {
     if (bus_num >= I2S_NUM_MAX) {
         return false;
@@ -170,13 +171,29 @@ bool i2sInitDmaItems(uint8_t bus_num) {
     I2S[bus_num].tx_queue = xQueueCreate(I2S_DMA_QUEUE_COUNT, sizeof(i2s_dma_item_t*));
     if (I2S[bus_num].tx_queue == NULL) {// memory error
         log_e("MEM ERROR!");
-        free(I2S[bus_num].dma_items);
+        heap_caps_free(I2S[bus_num].dma_items);
         I2S[bus_num].dma_items = NULL;
         return false;
     }
     return true;
 }
 
+bool i2sDeinitDmaItems(uint8_t bus_num) {
+    if (bus_num >= I2S_NUM_MAX) {
+        return false;
+    }
+    if (!I2S[bus_num].tx_queue) {
+        return false; // nothing to deinit
+    }
+
+    vQueueDelete(I2S[bus_num].tx_queue);
+    I2S[bus_num].tx_queue = NULL;
+    heap_caps_free(I2S[bus_num].dma_items);
+    I2S[bus_num].dma_items = NULL;
+
+    return true;
+}
+
 esp_err_t i2sSetClock(uint8_t bus_num, uint8_t div_num, uint8_t div_b, uint8_t div_a, uint8_t bck, uint8_t bits) {
     if (bus_num >= I2S_NUM_MAX || div_a > 63 || div_b > 63 || bck > 63) {
         return ESP_FAIL;
@@ -381,6 +398,10 @@ void i2sInit(uint8_t bus_num,
     esp_intr_enable(I2S[bus_num].isr_handle);
 }
 
+void i2sDeinit(uint8_t bus_num) {
+    i2sDeinitDmaItems(bus_num);
+}
+
 esp_err_t i2sSetSampleRate(uint8_t bus_num, uint32_t rate, uint8_t bits) {
     if (bus_num >= I2S_NUM_MAX) {
         return ESP_FAIL;

src/internal/Esp32_i2s.h

@@ -27,6 +27,8 @@ void i2sInit(uint8_t bus_num,
     size_t dma_count, 
     size_t dma_len);
 
+void i2sDeinit(uint8_t bus_num);
+
 void i2sSetPins(uint8_t bus_num, int8_t out, bool invert);
 
 esp_err_t i2sSetClock(uint8_t bus_num, uint8_t div_num, uint8_t div_b, uint8_t div_a, uint8_t bck, uint8_t bits_per_sample);

src/internal/NeoEsp32I2sMethod.h

@@ -170,9 +170,9 @@ public:
         }
 
         i2sSetPins(_bus.I2sBusNumber, -1, false);
-
+        i2sDeinit(_bus.I2sBusNumber);
         free(_data);
-        free(_i2sBuffer);
+        heap_caps_free(_i2sBuffer);
     }
 
     bool IsReadyToUpdate() const