Merge pull request arduino#18 from Seeed-Studio/feature-tinyusb-freertos

Make tinyusb work with freeRTOS

Author: LynnL4

cores/arduino/hooks.c

@@ -16,6 +16,7 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
+#include <stdint.h>
 /**
  * Empty yield() hook.
  *
@@ -25,23 +26,30 @@
  * Its defined as a weak symbol and it can be redefined to implement a
  * real cooperative scheduler.
  */
-static void __empty() {
-	// Empty
+extern void tud_task(void);
+extern uint32_t tud_cdc_n_write_flush (uint8_t itf);
+static void __empty()
+{
+// Empty
+#if defined(USE_TINYUSB)
+  tud_task();
+  tud_cdc_n_write_flush(0);
+#endif
 }
-
-void yield(void) __attribute__ ((weak, alias("__empty")));
+void yield(void) __attribute__((weak, alias("__empty")));
 
 /**
  * SysTick hook
  *
  * This function is called from SysTick handler, before the default
  * handler provided by Arduino.
  */
-static int __false() {
-	// Return false
-	return 0;
+static int __false()
+{
+  // Return false
+  return 0;
 }
-int sysTickHook(void) __attribute__ ((weak, alias("__false")));
+int sysTickHook(void) __attribute__((weak, alias("__false")));
 
 /**
  * SVC hook
@@ -50,10 +58,11 @@ int sysTickHook(void) __attribute__ ((weak, alias("__false")));
  * These functions are called from SVC handler, and PensSV handler.
  * Default action is halting.
  */
-static void __halt() {
-	// Halts
-	while (1)
-		;
+static void __halt()
+{
+  // Halts
+  while (1)
+    ;
 }
-void svcHook(void)    __attribute__ ((weak, alias("__halt")));
-void pendSVHook(void) __attribute__ ((weak, alias("__halt")));
+void svcHook(void) __attribute__((weak, alias("__halt")));
+void pendSVHook(void) __attribute__((weak, alias("__halt")));

cores/arduino/main.cpp

@@ -22,26 +22,33 @@
 // Weak empty variant initialization function.
 // May be redefined by variant files.
 void initVariant() __attribute__((weak));
-void initVariant() { }
+void initVariant() {}
+#if defined(USE_TINYUSB)
+// run TinyUSB background task auto This method will be overridden when running in FreeRTOS
+void __attribute__((weak)) tinyusb_task(void)
+{
+}
+#endif
 
 /*
  * _real_body(),_wrap_body() is a compiler trick,
  * user could overwrite the arduino setup/loop function by re-implement _wrap_body(),
  * calling of _real_body() in _wrap_body() is optional.
  */
-void _real_body(){
+void _real_body()
+{
   setup();
-
   for (;;)
   {
     loop();
     yield(); // yield run usb background task
-
-    if (serialEventRun) serialEventRun();
+    if (serialEventRun)
+      serialEventRun();
   }
 }
 
-void __attribute__((weak)) _wrap_body(){
+void __attribute__((weak)) _wrap_body()
+{
   _real_body();
 }
 
@@ -51,7 +58,7 @@ extern "C" void __libc_init_array(void);
 /*
  * \brief Main entry point of Arduino application
  */
-int main( void )
+int main(void)
 {
   init();
 
@@ -63,21 +70,11 @@ int main( void )
 
 #if defined(USE_TINYUSB)
   Adafruit_TinyUSB_Core_init();
+  tinyusb_task();
 #elif defined(USBCON)
   USBDevice.init();
   USBDevice.attach();
 #endif
   _wrap_body();
   return 0;
 }
-
-#if defined(USE_TINYUSB)
-
-// run TinyUSB background task when yield()
-extern  "C" void yield(void)
-{
-  tud_task();
-  tud_cdc_write_flush();
-}
-
-#endif