FatFs integration (SDIO backend) (#242)

extras/fatfs/syscall.c

@@ -0,0 +1,77 @@
+#include "ff.h"
+#include <FreeRTOS.h>
+
+#if _USE_LFN == 3   /* LFN with a working buffer on the heap */
+#include <stdlib.h>
+#endif
+
+#if _FS_REENTRANT
+
+/*
+ * Create a Synchronization Object
+ * This function is called in f_mount() function to create a new
+ * synchronization object, such as semaphore and mutex. When a 0 is returned,
+ * the f_mount() function fails with FR_INT_ERR.
+ */
+int ff_cre_syncobj(BYTE vol, xSemaphoreHandle *sobj)
+{
+    int ret;
+
+    *sobj = xSemaphoreCreateMutex();
+    ret = (int)(*sobj != NULL);
+
+    return ret;
+}
+
+/*
+ * Delete a Synchronization Object
+ * This function is called in f_mount() function to delete a synchronization
+ * object that created with ff_cre_syncobj() function. When a 0 is returned,
+ * the f_mount() function fails with FR_INT_ERR.
+ */
+int ff_del_syncobj(xSemaphoreHandle sobj)
+{
+    vSemaphoreDelete(sobj);
+    return 1;
+}
+
+/*
+ * Request Grant to Access the Volume
+ * This function is called on entering file functions to lock the volume.
+ * When a 0 is returned, the file function fails with FR_TIMEOUT.
+ */
+int ff_req_grant(xSemaphoreHandle sobj)
+{
+    return (int)(xSemaphoreTake(sobj, _FS_TIMEOUT) == pdTRUE);
+}
+
+/*
+ * Release Grant to Access the Volume
+ * This function is called on leaving file functions to unlock the volume.
+ */
+void ff_rel_grant(xSemaphoreHandle sobj)
+{
+    xSemaphoreGive(sobj);
+}
+
+#endif
+
+#if _USE_LFN == 3	/* LFN with a working buffer on the heap */
+/*
+ * Allocate a memory block
+ * If a NULL is returned, the file function fails with FR_NOT_ENOUGH_CORE.
+ */
+void* ff_memalloc(UINT msize)
+{
+    return malloc(msize);
+}
+
+/*
+ * Free a memory block
+ */
+void ff_memfree(void* mblock)
+{
+    free(mblock);
+}
+
+#endif