diff --git a/configs/cloudctrl/src/stm32_usb.c b/configs/cloudctrl/src/stm32_usb.c
index 337bb998cda..23c84917248 100644
--- a/configs/cloudctrl/src/stm32_usb.c
+++ b/configs/cloudctrl/src/stm32_usb.c
@@ -178,11 +178,26 @@ int stm32_usbhost_initialize(void)
    */
 
   uvdbg("Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB mass storage class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class\n");
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class\n");
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/ea3131/src/lpc31_usbhost.c b/configs/ea3131/src/lpc31_usbhost.c
index d2eefb11d75..25d431158c3 100644
--- a/configs/ea3131/src/lpc31_usbhost.c
+++ b/configs/ea3131/src/lpc31_usbhost.c
@@ -190,12 +190,22 @@ int lpc31_usbhost_initialize(void)
 #endif
 
 #ifdef CONFIG_USBHOST_MSC
-  /* Register theUSB host Mass Storage Class */
+  /* Register the USB host Mass Storage Class */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
+      usyslog(LOG_ERR, "ERROR: Failed to register the mass storage class: %d\n", ret);
+    }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class\n");
     }
 #endif
 
diff --git a/configs/mikroe-stm32f4/src/stm32_usb.c b/configs/mikroe-stm32f4/src/stm32_usb.c
index 1b0df8cedff..926c12e02d2 100644
--- a/configs/mikroe-stm32f4/src/stm32_usb.c
+++ b/configs/mikroe-stm32f4/src/stm32_usb.c
@@ -177,11 +177,26 @@ int stm32_usbhost_initialize(void)
    */
 
   uvdbg("Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB host Mass Storage Class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/olimex-lpc-h3131/src/lpc31_usbhost.c b/configs/olimex-lpc-h3131/src/lpc31_usbhost.c
index 1d876a1b892..e0a1e229d47 100644
--- a/configs/olimex-lpc-h3131/src/lpc31_usbhost.c
+++ b/configs/olimex-lpc-h3131/src/lpc31_usbhost.c
@@ -191,13 +191,23 @@ int lpc31_usbhost_initialize(void)
 #ifdef CONFIG_USBHOST_MSC
   /* Register theUSB host Mass Storage Class */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
       udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
 #endif
 
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class\n");
+    }
+#endif
+
 #ifdef CONFIG_USBHOST_HIDKBD
   /* Register the USB host HID keyboard class driver */
 
diff --git a/configs/olimex-lpc1766stk/src/lpc17_nsh.c b/configs/olimex-lpc1766stk/src/lpc17_nsh.c
index 0fa1413c17e..b4ab449f8ca 100644
--- a/configs/olimex-lpc1766stk/src/lpc17_nsh.c
+++ b/configs/olimex-lpc1766stk/src/lpc17_nsh.c
@@ -257,13 +257,25 @@ static int nsh_usbhostinitialize(void)
     }
 #endif
 
+#ifdef CONFIG_USBHOST_MSC
   /* Initialize mass storage support */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class\n");
+      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      syslog(LOG_ERR, "ERROR: Failed to register the CDC/ACM serial class: %d\n", eret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/olimex-stm32-p207/src/stm32_usb.c b/configs/olimex-stm32-p207/src/stm32_usb.c
index c663c948ff6..0dc678d5f21 100644
--- a/configs/olimex-stm32-p207/src/stm32_usb.c
+++ b/configs/olimex-stm32-p207/src/stm32_usb.c
@@ -175,6 +175,8 @@ int stm32_usbhost_initialize(void)
    * that we care about:
    */
 
+  uvdbg("Register class drivers\n");
+
 #ifdef CONFIG_USBHOST_HUB
   /* Initialize USB hub class support */
 
@@ -185,14 +187,25 @@ int stm32_usbhost_initialize(void)
     }
 #endif
 
-  /* Initialize Mass Storage Class support */
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB host Mass Storage Class */
 
-  uvdbg("Register class drivers\n");
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/open1788/src/lpc17_nsh.c b/configs/open1788/src/lpc17_nsh.c
index 00a12aec922..b972c224dbb 100644
--- a/configs/open1788/src/lpc17_nsh.c
+++ b/configs/open1788/src/lpc17_nsh.c
@@ -312,11 +312,26 @@ static int nsh_usbhostinitialize(void)
    */
 
   syslog(LOG_INFO, "Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB host Mass Storage Class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class\n");
+      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      syslog(LOG_ERR, "ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/pic32mx-starterkit/src/pic32mx_nsh.c b/configs/pic32mx-starterkit/src/pic32mx_nsh.c
index 7a3813d56ec..d18f63d06df 100644
--- a/configs/pic32mx-starterkit/src/pic32mx_nsh.c
+++ b/configs/pic32mx-starterkit/src/pic32mx_nsh.c
@@ -276,11 +276,26 @@ static int nsh_usbhostinitialize(void)
    */
 
   syslog(LOG_INFO, "Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB host Mass Storage Class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class\n");
+      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      syslog(LOG_ERR, "ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/pic32mx7mmb/src/pic32_nsh.c b/configs/pic32mx7mmb/src/pic32_nsh.c
index f0b1e9e5b9e..8c51f1a2ba9 100644
--- a/configs/pic32mx7mmb/src/pic32_nsh.c
+++ b/configs/pic32mx7mmb/src/pic32_nsh.c
@@ -286,11 +286,26 @@ static int nsh_usbhostinitialize(void)
    */
 
   syslog(LOG_INFO, "Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB host Mass Storage Class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class\n");
+      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      syslog(LOG_ERR, "ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/sama5d3-xplained/src/sam_usb.c b/configs/sama5d3-xplained/src/sam_usb.c
index fc40510934e..fd4bf54b26b 100644
--- a/configs/sama5d3-xplained/src/sam_usb.c
+++ b/configs/sama5d3-xplained/src/sam_usb.c
@@ -315,13 +315,23 @@ int sam_usbhost_initialize(void)
 #ifdef CONFIG_USBHOST_MSC
   /* Register theUSB host Mass Storage Class */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
       udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
 #endif
 
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_USBHOST_HIDKBD
   /* Register the USB host HID keyboard class driver */
 
diff --git a/configs/sama5d3x-ek/src/sam_usb.c b/configs/sama5d3x-ek/src/sam_usb.c
index a7ea40ed13a..f018d4f9614 100644
--- a/configs/sama5d3x-ek/src/sam_usb.c
+++ b/configs/sama5d3x-ek/src/sam_usb.c
@@ -313,13 +313,23 @@ int sam_usbhost_initialize(void)
 #ifdef CONFIG_USBHOST_MSC
   /* Register the USB host Mass Storage Class */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
       udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
 #endif
 
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_USBHOST_HIDKBD
   /* Register the USB host HID keyboard class driver */
 
diff --git a/configs/sama5d4-ek/src/sam_usb.c b/configs/sama5d4-ek/src/sam_usb.c
index ef6c28bbe1e..4ba85b84d87 100644
--- a/configs/sama5d4-ek/src/sam_usb.c
+++ b/configs/sama5d4-ek/src/sam_usb.c
@@ -314,13 +314,23 @@ int sam_usbhost_initialize(void)
 #ifdef CONFIG_USBHOST_MSC
   /* Register the USB host Mass Storage Class */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
       udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
 #endif
 
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_USBHOST_HIDKBD
   /* Register the USB host HID keyboard class driver */
 
diff --git a/configs/shenzhou/src/stm32_usb.c b/configs/shenzhou/src/stm32_usb.c
index 90840018d88..c0ea7dbbddb 100644
--- a/configs/shenzhou/src/stm32_usb.c
+++ b/configs/shenzhou/src/stm32_usb.c
@@ -177,11 +177,26 @@ int stm32_usbhost_initialize(void)
    */
 
   uvdbg("Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB mass storage class class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/stm3220g-eval/src/stm32_usb.c b/configs/stm3220g-eval/src/stm32_usb.c
index fda57cb8802..d037d8bb6fd 100644
--- a/configs/stm3220g-eval/src/stm32_usb.c
+++ b/configs/stm3220g-eval/src/stm32_usb.c
@@ -177,11 +177,26 @@ int stm32_usbhost_initialize(void)
    */
 
   uvdbg("Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB mass storage class class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/stm3240g-eval/src/stm32_usb.c b/configs/stm3240g-eval/src/stm32_usb.c
index a9a8be2b0f0..449c80af8eb 100644
--- a/configs/stm3240g-eval/src/stm32_usb.c
+++ b/configs/stm3240g-eval/src/stm32_usb.c
@@ -177,11 +177,26 @@ int stm32_usbhost_initialize(void)
    */
 
   uvdbg("Register class drivers\n");
-  ret = usbhost_storageinit();
+
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB mass storage class class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/stm32f429i-disco/src/stm32_usb.c b/configs/stm32f429i-disco/src/stm32_usb.c
index e2b47e588b7..291c025730d 100644
--- a/configs/stm32f429i-disco/src/stm32_usb.c
+++ b/configs/stm32f429i-disco/src/stm32_usb.c
@@ -184,13 +184,25 @@ int stm32_usbhost_initialize(void)
     }
 #endif
 
-  /* Register the USB host Mass Storage Class */
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB mass storage class class */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */
 
diff --git a/configs/stm32f4discovery/src/stm32_usb.c b/configs/stm32f4discovery/src/stm32_usb.c
index 96e5a2a37c2..24f35f726a1 100644
--- a/configs/stm32f4discovery/src/stm32_usb.c
+++ b/configs/stm32f4discovery/src/stm32_usb.c
@@ -188,12 +188,22 @@ int stm32_usbhost_initialize(void)
 #endif
 
 #ifdef CONFIG_USBHOST_MSC
-  /* Initialize the mass storage class */
+  /* Register the USB mass storage class class */
 
-  ret = usbhost_storageinit();
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      udbg("Failed to register the mass storage class\n");
+      udbg("ERROR: Failed to register the mass storage class: %d\n", ret);
+    }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      udbg("ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
     }
 #endif
 
diff --git a/configs/sure-pic32mx/src/pic32mx_nsh.c b/configs/sure-pic32mx/src/pic32mx_nsh.c
index 47522a275f6..4aa2febcc40 100644
--- a/configs/sure-pic32mx/src/pic32mx_nsh.c
+++ b/configs/sure-pic32mx/src/pic32mx_nsh.c
@@ -278,11 +278,25 @@ static int nsh_usbhostinitialize(void)
 
   syslog(LOG_INFO, "Register class drivers\n");
 
-  ret = usbhost_storageinit();
+#ifdef CONFIG_USBHOST_MSC
+  /* Register the USB mass storage class class */
+
+  ret = usbhost_msc_initialize();
   if (ret != OK)
     {
-      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class\n");
+      syslog(LOG_ERR, "ERROR: Failed to register the mass storage class: %d\n", ret);
     }
+#endif
+
+#ifdef CONFIG_USBHOST_CDCACM
+  /* Register the CDC/ACM serial class */
+
+  ret = usbhost_cdcacm_initialize();
+  if (ret != OK)
+    {
+      syslog(LOG_ERR, "ERROR: Failed to register the CDC/ACM serial class: %d\n", ret);
+    }
+#endif
 
   /* Then get an instance of the USB host interface */