Fix lufa sendchar() infinite wait loop

- FrameNumber is not updated when adapter powered
- can be blocked in sendchar() when pluged into AC adapter

keyboard/hhkb_rn42/rn42/main.c

@@ -17,8 +17,8 @@
 
 static int8_t sendchar_func(uint8_t c)
 {
-    sendchar(c);    // LUFA
     xmit(c);        // SUART
+    sendchar(c);    // LUFA
     return 0;
 }
 
@@ -85,6 +85,7 @@ int main(void)
     print("Keyboard start.\n");
     while (1) {
         while (USB_DeviceState == DEVICE_STATE_Suspended) {
+            print("[s]");
             suspend_power_down();
             if (USB_Device_RemoteWakeupEnabled && suspend_wakeup_condition()) {
                     USB_Device_SendRemoteWakeup();

protocol/lufa/lufa.c

@@ -148,6 +148,7 @@ static void Console_Task(void)
 */
 void EVENT_USB_Device_Connect(void)
 {
+    print("[C]");
     /* For battery powered device */
     if (!USB_IsInitialized) {
         USB_Init();
@@ -157,6 +158,7 @@ void EVENT_USB_Device_Connect(void)
 
 void EVENT_USB_Device_Disconnect(void)
 {
+    print("[D]");
     /* For battery powered device */
 /* TODO: This doesn't work. After several plug in/outs can not be enumerated. 
     if (USB_IsInitialized) {
@@ -169,10 +171,12 @@ void EVENT_USB_Device_Disconnect(void)
 
 void EVENT_USB_Device_Reset(void)
 {
+    print("[R]");
 }
 
 void EVENT_USB_Device_Suspend()
 {
+    print("[S]");
 #ifdef SLEEP_LED_ENABLE
     sleep_led_enable();
 #endif
@@ -180,6 +184,7 @@ void EVENT_USB_Device_Suspend()
 
 void EVENT_USB_Device_WakeUp()
 {
+    print("[W]");
     suspend_wakeup_init();
 
 #ifdef SLEEP_LED_ENABLE
@@ -489,37 +494,28 @@ int8_t sendchar(uint8_t c)
     uint8_t ep = Endpoint_GetCurrentEndpoint();
     Endpoint_SelectEndpoint(CONSOLE_IN_EPNUM);
     if (!Endpoint_IsEnabled() || !Endpoint_IsConfigured()) {
-        Endpoint_SelectEndpoint(ep);
-        return -1;
+        goto ERROR_EXIT;
     }
 
     if (timeouted && !Endpoint_IsReadWriteAllowed()) {
-        Endpoint_SelectEndpoint(ep);
-        return - 1;
+        goto ERROR_EXIT;
     }
 
     timeouted = false;
 
     uint8_t timeout = SEND_TIMEOUT;
-    uint16_t prevFN = USB_Device_GetFrameNumber();
     while (!Endpoint_IsReadWriteAllowed()) {
-        switch (USB_DeviceState) {
-        case DEVICE_STATE_Unattached:
-        case DEVICE_STATE_Suspended:
-            return -1;
+        if (USB_DeviceState != DEVICE_STATE_Configured) {
+            goto ERROR_EXIT;
         }
         if (Endpoint_IsStalled()) {
-            Endpoint_SelectEndpoint(ep);
-            return -1;
+            goto ERROR_EXIT;
         }
-        if (prevFN != USB_Device_GetFrameNumber()) {
-            if (!(timeout--)) {
-                timeouted = true;
-                Endpoint_SelectEndpoint(ep);
-                return -1;
-            }
-            prevFN = USB_Device_GetFrameNumber();
+        if (!(timeout--)) {
+            timeouted = true;
+            goto ERROR_EXIT;
         }
+        _delay_ms(1);
     }
 
     Endpoint_Write_8(c);
@@ -530,6 +526,9 @@ int8_t sendchar(uint8_t c)
 
     Endpoint_SelectEndpoint(ep);
     return 0;
+ERROR_EXIT:
+    Endpoint_SelectEndpoint(ep);
+    return -1;
 }
 #else
 int8_t sendchar(uint8_t c)
@@ -587,6 +586,7 @@ int main(void)
     print("Keyboard start.\n");
     while (1) {
         while (USB_DeviceState == DEVICE_STATE_Suspended) {
+            print("[s]");
             suspend_power_down();
             if (USB_Device_RemoteWakeupEnabled && suspend_wakeup_condition()) {
                     USB_Device_SendRemoteWakeup();