usb: Skeleton platform code for FTDI FT4222 USB to i2c bridge

Signed-off-by: Henry Bruce <henry.bruce@intel.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

src/usb/usb.c

@@ -0,0 +1,51 @@
+/*
+ * Author: Henry Bruce <henry.bruce@intel.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "mraa_internal.h"
+#include "usb/ftdi_ft4222.h"
+
+
+mraa_platform_t
+mraa_usb_platform_extender(mraa_board_t* board)
+{
+    mraa_platform_t platform_type = MRAA_UNKNOWN_PLATFORM;
+    if (mraa_ftdi_ft4222_init() == MRAA_SUCCESS) {
+        unsigned int versionChip, versionLib;
+        if (mraa_ftdi_ft4222_get_version(&versionChip, &versionLib) == MRAA_SUCCESS) {
+            // TODO: Add ft4222 version checks
+            platform_type = MRAA_FTDI_FT4222;        
+        }
+    }  
+    switch (platform_type) {
+        case MRAA_FTDI_FT4222:
+            mraa_ftdi_ft4222(board);
+            break;
+        default:
+            syslog(LOG_ERR, "Unknown USB Platform Extender, currently not supported by MRAA");
+    }
+    return platform_type;
+}