Fix spurious connection and disconnection

* call USBHost::getHostInst() in connect(), so constructor order is not important and evey clock is already configured when called
* on detach, the callback should be called, but this doesn't work if MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL is set to 1 (crashes in vtable), Since Callback.h is an header only file, redefine MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL to 0 before including (yes, it's a ugly hack)

Author: facchinm

examples/DirList/DirList.ino

@@ -85,4 +85,9 @@ void setup()
 
 void loop()
 {
+    delay(1000);
+    // handle disconnection and reconnection
+    if (!msd.connected()) {
+        msd.connect();
+    }
 }

examples/FileRead/FileRead.ino

@@ -72,5 +72,9 @@ void setup() {
 }
 
 void loop() {
-
+    delay(1000);
+    // handle disconnection and reconnection
+    if (!msd.connected()) {
+        msd.connect();
+    }
 }

examples/FileWrite/FileWrite.ino

@@ -71,5 +71,9 @@ void setup() {
 }
 
 void loop() {
-
+    delay(1000);
+    // handle disconnection and reconnection
+    if (!msd.connected()) {
+        msd.connect();
+    }
 }

examples/PortentaOTA/PortentaOTA.ino

@@ -198,4 +198,9 @@ void setup()
 
 void loop()
 {
+    delay(1000);
+    // handle disconnection and reconnection
+    if (!msd.connected()) {
+        msd.connect();
+    }
 }

src/USBHost/USBDeviceConnected.h

@@ -21,6 +21,8 @@
 #include "USBHost/USBEndpoint.h"
 #include "USBHost/USBHostConf.h"
 #include "rtos.h"
+#undef MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL
+#define MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL  0
 #include "Callback.h"
 
 class USBHostHub;

src/USBHost/USBEndpoint.h

@@ -17,6 +17,8 @@
 #ifndef USBENDPOINT_H
 #define USBENDPOINT_H
 
+#undef MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL
+#define MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL  0
 #include "Callback.h"
 #include "USBHostTypes.h"
 #include "rtos.h"

src/USBHost/USBHostConf.h

@@ -17,6 +17,9 @@
 #ifndef USBHOST_CONF_H
 #define USBHOST_CONF_H
 
+#undef MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL
+#define MBED_CONF_PLATFORM_CALLBACK_NONTRIVIAL  0
+#include "Callback.h"
 #include "Arduino.h"
 
 #if defined(TARGET_STM)

src/USBHost3GModule/WANDongle.cpp

@@ -29,7 +29,6 @@
 
 WANDongle::WANDongle() : m_pInitializer(NULL), m_serialCount(0), m_totalInitializers(0)
 {
-    host = USBHost::getHostInst();
     init();
 }
 
@@ -48,6 +47,7 @@ bool WANDongle::tryConnect()
       USB_DBG("Device is already connected!");
       return true;
   }
+  host = USBHost::getHostInst();
 
   m_pInitializer = NULL;
 

src/USBHostHID/USBHostKeyboard.cpp

@@ -87,7 +87,6 @@ static uint8_t keymap[4][0x39] = {
 
 USBHostKeyboard::USBHostKeyboard()
 {
-    host = USBHost::getHostInst();
     init();
 }
 
@@ -116,6 +115,7 @@ bool USBHostKeyboard::connect()
     if (dev_connected) {
         return true;
     }
+    host = USBHost::getHostInst();
 
     for (uint8_t i = 0; i < MAX_DEVICE_CONNECTED; i++) {
         if ((dev = host->getDevice(i)) != NULL) {

src/USBHostHID/USBHostMouse.cpp

@@ -20,7 +20,6 @@
 
 USBHostMouse::USBHostMouse()
 {
-    host = USBHost::getHostInst();
     init();
 }
 
@@ -56,6 +55,7 @@ bool USBHostMouse::connect()
     if (dev_connected) {
         return true;
     }
+    host = USBHost::getHostInst();
 
     for (uint8_t i = 0; i < MAX_DEVICE_CONNECTED; i++) {
         if ((dev = host->getDevice(i)) != NULL) {