Add device connected callback to USBHost.

Add setEnumeratingDeviceIndex to IUSBEnumerator.h

Author: AndrewCapon

Diff for: src/USBHost/IUSBEnumerator.h

@@ -31,6 +31,7 @@ class IUSBEnumerator
     virtual bool parseInterface(uint8_t intf_nb, uint8_t intf_class, uint8_t intf_subclass, uint8_t intf_protocol) = 0; //Must return true if the interface should be parsed
     virtual bool useEndpoint(uint8_t intf_nb, ENDPOINT_TYPE type, ENDPOINT_DIRECTION dir) = 0; //Must return true if the endpoint will be used
     virtual void parseConfigEntry(uint8_t type, uint8_t sub_type, uint8_t *data, uint32_t len) {};
+    virtual void setEnumeratingDeviceIndex(int index) {};
 };
 
 #endif /*IUSBENUMERATOR_H_*/

Diff for: src/USBHost/USBHost.cpp

@@ -225,6 +225,8 @@ void USBHost::usb_process()
 
                         if ((i < MAX_DEVICE_CONNECTED) && !too_many_hub) {
                             deviceInUse[i] = true;
+                            if(device_connected_callback)
+                              device_connected_callback(i);
                         }
 
                     } while(0);
@@ -960,6 +962,7 @@ USB_TYPE USBHost::enumerate(USBDeviceConnected * dev, IUSBEnumerator* pEnumerato
         dev->setPid(data[10] | (data[11] << 8));
         USB_DBG("CLASS: %02X \t VID: %04X \t PID: %04X", data[4], data[8] | (data[9] << 8), data[10] | (data[11] << 8));
 
+        pEnumerator->setEnumeratingDeviceIndex(index);
         pEnumerator->setVidPid( data[8] | (data[9] << 8), data[10] | (data[11] << 8) );
 
         res = getConfigurationDescriptor(dev, data, sizeof(data), &total_conf_descr_length);

Diff for: src/USBHost/USBHost.h

@@ -189,6 +189,15 @@ class USBHost : public USBHALHost {
         }
     }
 
+
+    /**
+     * Callback for connected device index
+     */
+    void setDeviceConnectedCallback(mbed::Callback<void(uint8_t uDeviceIndex)> callback)
+    {
+      device_connected_callback = callback;
+    }
+
     /**
      * Instantiate to protect USB thread from accessing shared objects (USBConnectedDevices and Interfaces)
      */
@@ -287,6 +296,8 @@ class USBHost : public USBHALHost {
     // buffer for conf descriptor
     uint8_t data[415];
 
+    mbed::Callback<void(uint8_t uDeviceIndex)> device_connected_callback = nullptr;
+    
     /**
     * Add a transfer on the TD linked list associated to an ED
     *