diff --git a/boards/embedded_artists/ea4357/board_ea4357.c b/boards/embedded_artists/ea4357/board_ea4357.c
index d0ac98be..ce38a692 100644
--- a/boards/embedded_artists/ea4357/board_ea4357.c
+++ b/boards/embedded_artists/ea4357/board_ea4357.c
@@ -45,7 +45,7 @@
 #define BOARD_UART_PIN_TX         10 // PF.10 : UART0_TXD
 #define BOARD_UART_PIN_RX         11 // PF.11 : UART0_RXD
 
-const static struct {
+static const struct {
   uint8_t mux_port;
   uint8_t mux_pin;
 
diff --git a/demos/host/src/cdc_serial_app.c b/demos/host/src/cdc_serial_app.c
index 208cb28a..6c9e2359 100644
--- a/demos/host/src/cdc_serial_app.c
+++ b/demos/host/src/cdc_serial_app.c
@@ -86,16 +86,15 @@ void tusbh_cdc_xfer_isr(uint8_t dev_addr, tusb_event_t event, cdc_pipeid_t pipe_
         case TUSB_EVENT_XFER_COMPLETE:
           received_bytes = xferred_bytes;
           osal_semaphore_post(sem_hdl);  // notify main task
-          break;
+        break;
 
         case TUSB_EVENT_XFER_ERROR:
           received_bytes = 0; // ignore
-          break;
+        break;
 
         case TUSB_EVENT_XFER_STALLED:
         default :
-          ASSERT(false, VOID_RETURN);
-          break;
+        break;
       }
     break;
 
diff --git a/demos/host/src/cli.c b/demos/host/src/cli.c
index 6abf1467..b3bdb396 100644
--- a/demos/host/src/cli.c
+++ b/demos/host/src/cli.c
@@ -92,7 +92,7 @@ static char const * const cli_error_message[] =
 #define CLI_PROTOTYPE_EXPAND(command, function, description) \
     cli_error_t function(char * p_para);
 
-CLI_COMMAND_TABLE(CLI_PROTOTYPE_EXPAND);
+CLI_COMMAND_TABLE(CLI_PROTOTYPE_EXPAND)
 
 //--------------------------------------------------------------------+
 // Expand to enum value
diff --git a/demos/host/src/keyboard_app.c b/demos/host/src/keyboard_app.c
index 07e65ce7..a6631a76 100644
--- a/demos/host/src/keyboard_app.c
+++ b/demos/host/src/keyboard_app.c
@@ -133,14 +133,11 @@ OSAL_TASK_FUNCTION( keyboard_app_task ) (void* p_task_para)
 //--------------------------------------------------------------------+
 
 // look up new key in previous keys
-static inline bool is_key_in_report(hid_keyboard_report_t const *p_report, uint8_t modifier, uint8_t keycode)
+static inline bool is_key_in_report(hid_keyboard_report_t const *p_report, uint8_t keycode)
 {
   for(uint8_t i=0; i<6; i++)
   {
-    if (p_report->keycode[i] == keycode)
-    {
-      return true;
-    }
+    if (p_report->keycode[i] == keycode)  return true;
   }
 
   return false;
@@ -148,19 +145,19 @@ static inline bool is_key_in_report(hid_keyboard_report_t const *p_report, uint8
 
 static inline void process_kbd_report(hid_keyboard_report_t const *p_new_report)
 {
-  static hid_keyboard_report_t prev_report = { 0 }; // previous report to check key released
+  static hid_keyboard_report_t prev_report = { 0, 0, {0} }; // previous report to check key released
 
   //------------- example code ignore control (non-printable) key affects -------------//
   for(uint8_t i=0; i<6; i++)
   {
     if ( p_new_report->keycode[i] )
     {
-      if ( is_key_in_report(&prev_report, p_new_report->modifier, p_new_report->keycode[i]) )
+      if ( is_key_in_report(&prev_report, p_new_report->keycode[i]) )
       {
-        // previously existed means holding
+        // exist in previous report means the current key is holding
       }else
       {
-        // previously non-existed means key is pressed
+        // not exist in previous report means the current key is pressed
         uint8_t ch = keycode_to_ascii(p_new_report->modifier, p_new_report->keycode[i]);
         putchar(ch);
         if ( ch == '\r' ) putchar('\n'); // added new line for enter key
diff --git a/demos/host/src/main.c b/demos/host/src/main.c
index 7ebb389b..e3023bf6 100644
--- a/demos/host/src/main.c
+++ b/demos/host/src/main.c
@@ -109,7 +109,6 @@ void os_none_start_scheduler(void)
     msc_app_task(NULL);
     cdc_serial_app_task(NULL);
     rndis_app_task(NULL);
-
   }
 }
 #endif
@@ -144,8 +143,6 @@ int main(void)
   #error need to start RTOS schduler
 #endif
 
-  while(1) { } // should not be reached here
-
   return 0;
 }
 
diff --git a/demos/host/src/mouse_app.c b/demos/host/src/mouse_app.c
index 4fabd4f3..6fdba459 100644
--- a/demos/host/src/mouse_app.c
+++ b/demos/host/src/mouse_app.c
@@ -122,6 +122,8 @@ OSAL_TASK_FUNCTION( mouse_app_task ) (void* p_task_para)
   OSAL_TASK_LOOP_BEGIN
 
   osal_queue_receive(queue_mouse_hdl, &mouse_report, OSAL_TIMEOUT_WAIT_FOREVER, &error);
+	(void) error; // supporess compiler's warninig
+	
   process_mouse_report(&mouse_report);
 
   OSAL_TASK_LOOP_END
@@ -162,7 +164,7 @@ void cursor_movement(int8_t x, int8_t y, int8_t wheel)
 
 static inline void process_mouse_report(hid_mouse_report_t const * p_report)
 {
-  static hid_mouse_report_t prev_report = { 0 };
+  static hid_mouse_report_t prev_report = { 0, 0, 0, 0 };
 
   //------------- button state  -------------//
   uint8_t button_changed_mask = p_report->buttons ^ prev_report.buttons;
diff --git a/demos/host/src/tusb_config.h b/demos/host/src/tusb_config.h
index 13362054..30fc5eae 100644
--- a/demos/host/src/tusb_config.h
+++ b/demos/host/src/tusb_config.h
@@ -68,7 +68,7 @@
 #define TUSB_CFG_HOST_HID_KEYBOARD              1
 #define TUSB_CFG_HOST_HID_MOUSE                 1
 #define TUSB_CFG_HOST_HID_GENERIC               0
-#define TUSB_CFG_HOST_MSC                       0
+#define TUSB_CFG_HOST_MSC                       1
 #define TUSB_CFG_HOST_CDC                       1
 #define TUSB_CFG_HOST_CDC_RNDIS                 0
 
diff --git a/tinyusb/class/msc_host.c b/tinyusb/class/msc_host.c
index 1380b1e0..e81bed25 100644
--- a/tinyusb/class/msc_host.c
+++ b/tinyusb/class/msc_host.c
@@ -377,7 +377,7 @@ tusb_error_t msch_open_subtask(uint8_t dev_addr, tusb_descriptor_interface_t con
     SUBTASK_ASSERT_STATUS(error);
 
     //------------- SCSI Request Sense -------------//
-    tusbh_msc_request_sense(dev_addr, 0, msch_buffer);
+    (void) tusbh_msc_request_sense(dev_addr, 0, msch_buffer);
     osal_semaphore_wait(msch_sem_hdl, SCSI_XFER_TIMEOUT, &error);
     SUBTASK_ASSERT_STATUS(error);
 
diff --git a/tinyusb/host/ehci/ehci.c b/tinyusb/host/ehci/ehci.c
index 9d606e18..c20112d7 100644
--- a/tinyusb/host/ehci/ehci.c
+++ b/tinyusb/host/ehci/ehci.c
@@ -123,7 +123,7 @@ static ehci_link_t*  list_find_previous_item(ehci_link_t* p_head, ehci_link_t* p
 static tusb_error_t list_remove_qhd(ehci_link_t* p_head, ehci_link_t* p_remove);
 
 static tusb_error_t hcd_controller_init(uint8_t hostid) ATTR_WARN_UNUSED_RESULT;
-static tusb_error_t hcd_controller_stop(uint8_t hostid) ATTR_WARN_UNUSED_RESULT;
+static tusb_error_t hcd_controller_stop(uint8_t hostid) ATTR_WARN_UNUSED_RESULT ATTR_UNUSED;
 
 //--------------------------------------------------------------------+
 // USBH-HCD API
@@ -278,20 +278,6 @@ static tusb_error_t hcd_controller_stop(uint8_t hostid)
   return timeout_expired(&timeout) ? TUSB_ERROR_OSAL_TIMEOUT : TUSB_ERROR_NONE;
 }
 
-//tusb_error_t hcd_controller_reset(uint8_t hostid)
-//{
-//  ehci_registers_t* const regs = get_operational_register(hostid);
-//  timeout_timer_t timeout;
-//
-//// NXP chip powered with non-host mode --> sts bit is not correctly reflected
-//  regs->usb_cmd_bit.reset = 1;
-//
-//  timeout_set(&timeout, 2); // should not take longer the time to stop controller
-//  while( regs->usb_cmd_bit.reset && !timeout_expired(&timeout)) {}
-//
-//  return timeout_expired(&timeout) ? TUSB_ERROR_OSAL_TIMEOUT : TUSB_ERROR_NONE;
-//}
-
 //--------------------------------------------------------------------+
 // CONTROL PIPE API
 //--------------------------------------------------------------------+
diff --git a/tinyusb/host/hub.h b/tinyusb/host/hub.h
index b6cdd599..956dee50 100644
--- a/tinyusb/host/hub.h
+++ b/tinyusb/host/hub.h
@@ -200,7 +200,6 @@ tusb_error_t hub_open_subtask(uint8_t dev_addr, tusb_descriptor_interface_t cons
 void         hub_isr(pipe_handle_t pipe_hdl, tusb_event_t event, uint32_t xferred_bytes);
 void         hub_close(uint8_t dev_addr);
 
-tusb_error_t hub_status_pipe_queue(uint8_t dev_addr);
 #endif
 
 #ifdef __cplusplus
diff --git a/tinyusb/osal/osal_none.h b/tinyusb/osal/osal_none.h
index 300233f4..3cb869bd 100644
--- a/tinyusb/osal/osal_none.h
+++ b/tinyusb/osal/osal_none.h
@@ -36,12 +36,6 @@
 */
 /**************************************************************************/
 
-/** \file
- *  \brief TBD
- *
- *  \note TBD
- */
-
 /** \ingroup TBD
  *  \defgroup TBD
  *  \brief TBD