Fix small things noticed in MR, add documentation

components/freertos/include/freertos/heap_regions.h

@@ -19,19 +19,68 @@
 /* The maximum amount of tags in use */
 #define HEAPREGIONS_MAX_TAGCOUNT 16
 
-
+/**
+ * @brief Structure to define a memory region
+ */
 typedef struct HeapRegionTagged
 {
-	uint8_t *pucStartAddress;
-	size_t xSizeInBytes;
-	BaseType_t xTag;
-	uint32_t xExecAddr;
+    uint8_t *pucStartAddress;       ///< Start address of the region
+    size_t xSizeInBytes;            ///< Size of the region
+    BaseType_t xTag;                ///< Tag for the region
+    uint32_t xExecAddr;             ///< If non-zero, indicates the region also has an alias in IRAM.
 } HeapRegionTagged_t;
 
+/**
+ * @brief Initialize the heap allocator by feeding it the usable memory regions and their tags.
+ *
+ * This takes an array of heapRegionTagged_t structs, the last entry of which is a dummy entry
+ * which has pucStartAddress set to NULL. It will initialize the heap allocator to serve memory
+ * from these ranges.
+ *
+ * @param  pxHeapRegions Array of region definitions
+ */
 
 void vPortDefineHeapRegionsTagged( const HeapRegionTagged_t * const pxHeapRegions );
+
+
+/**
+ * @brief Allocate memory from a region with a certain tag
+ *
+ * Like pvPortMalloc, this returns an allocated chunk of memory. This function,
+ * however, forces the allocator to allocate from a region specified by a
+ * specific tag.
+ *
+ * @param  xWantedSize Size needed, in bytes
+ * @param  tag Tag of the memory region the allocation has to be from
+ *
+ * @return Pointer to allocated memory if succesful.
+ *         NULL if unsuccesful.
+ */
 void *pvPortMallocTagged( size_t xWantedSize, BaseType_t tag );
+
+/**
+ * @brief Get the lowest amount of memory free for a certain tag
+ *
+ * This function allows the user to see what the least amount of
+ * free memory for a certain tag is.
+ * 
+ * @param  tag Tag of the memory region
+ *
+ * @return Minimum amount of free bytes available in the runtime of
+ *         the program
+ */
 size_t xPortGetMinimumEverFreeHeapSizeTagged( BaseType_t tag );
+
+/**
+ * @brief Get the amount of free bytes in a certain tagged region
+ *
+ * Works like xPortGetFreeHeapSize but allows the user to specify
+ * a specific tag
+ * 
+ * @param  tag Tag of the memory region
+ *
+ * @return Remaining amount of free bytes in region
+ */
 size_t xPortGetFreeHeapSizeTagged( BaseType_t tag );