Add DWC2 Test Mode SUpport

src/device/dcd.h

@@ -58,6 +58,7 @@ typedef enum
 
   DCD_EVENT_SETUP_RECEIVED,
   DCD_EVENT_XFER_COMPLETE,
+  DCD_EVENT_TEST_MODE,
 
   // Not an DCD event, just a convenient way to defer ISR function
   USBD_EVENT_FUNC_CALL,
@@ -97,9 +98,23 @@ typedef struct TU_ATTR_ALIGNED(4)
       void (*func) (void*);
       void* param;
     }func_call;
+
+    // TEST MODE
+    struct {
+      uint8_t selector;
+    }test_mode;
   };
 } dcd_event_t;
 
+typedef enum _test_mode_selector
+{
+  TEST_J = 1,
+  TEST_K,
+  TEST_SE0_NAK,
+  TEST_PACKET,
+  TEST_FORCE_ENABLE,
+} test_mode_t;
+
 //TU_VERIFY_STATIC(sizeof(dcd_event_t) <= 12, "size is not correct");
 
 //--------------------------------------------------------------------+
@@ -149,6 +164,12 @@ void dcd_disconnect(uint8_t rhport) TU_ATTR_WEAK;
 // Enable/Disable Start-of-frame interrupt. Default is disabled
 void dcd_sof_enable(uint8_t rhport, bool en);
 
+// Check if the test mode is supported
+bool dcd_test_mode_supported(test_mode_t test_selector) TU_ATTR_WEAK;
+
+// Put device into a test mode (needs power cycle to quit)
+void dcd_enter_test_mode(uint8_t rhport, test_mode_t test_selector) TU_ATTR_WEAK;
+
 //--------------------------------------------------------------------+
 // Endpoint API
 //--------------------------------------------------------------------+
@@ -240,6 +261,13 @@ static inline void dcd_event_sof(uint8_t rhport, uint32_t frame_count, bool in_i
   dcd_event_handler(&event, in_isr);
 }
 
+TU_ATTR_ALWAYS_INLINE static inline void dcd_event_enter_test_mode(uint8_t rhport, uint8_t test_selector, bool in_isr)
+{
+  dcd_event_t event = { .rhport = rhport, .event_id = DCD_EVENT_TEST_MODE };
+  event.test_mode.selector = test_selector;
+  dcd_event_handler(&event, in_isr);
+}
+
 #ifdef __cplusplus
  }
 #endif