update some sense warning from -Wconversion

src/class/cdc/cdc_device.c

@@ -229,7 +229,7 @@ void cdcd_init(void)
   {
     cdcd_interface_t* p_cdc = &_cdcd_itf[i];
 
-    p_cdc->wanted_char = -1;
+    p_cdc->wanted_char = (char) -1;
 
     // default line coding is : stop bit = 1, parity = none, data bits = 8
     p_cdc->line_coding.bit_rate  = 115200;

src/class/msc/msc_device.c

@@ -152,7 +152,7 @@ static inline uint16_t rdwr10_get_blocksize(msc_cbw_t const* cbw)
   // invalid block count
   if (block_count == 0) return 0;
 
-  return cbw->total_bytes / block_count;
+  return (uint16_t) (cbw->total_bytes / block_count);
 }
 
 uint8_t rdwr10_validate_cmd(msc_cbw_t const* cbw)

src/tusb.c

@@ -109,9 +109,9 @@ bool tu_edpt_validate(tusb_desc_endpoint_t const * desc_ep, tusb_speed_t speed)
 void tu_edpt_bind_driver(uint8_t ep2drv[][2], tusb_desc_interface_t const* desc_itf, uint16_t desc_len, uint8_t driver_id)
 {
   uint8_t const* p_desc = (uint8_t const*) desc_itf;
-  uint16_t len = 0;
+  uint8_t const* desc_end = p_desc + desc_len;
 
-  while( len < desc_len )
+  while( p_desc < desc_end )
   {
     if ( TUSB_DESC_ENDPOINT == tu_desc_type(p_desc) )
     {
@@ -121,7 +121,6 @@ void tu_edpt_bind_driver(uint8_t ep2drv[][2], tusb_desc_interface_t const* desc_
       ep2drv[tu_edpt_number(ep_addr)][tu_edpt_dir(ep_addr)] = driver_id;
     }
 
-    len   += (uint16_t) tu_desc_len(p_desc);
     p_desc = tu_desc_next(p_desc);
   }
 }