diff --git a/examples/device/cdc_msc/src/msc_disk.c b/examples/device/cdc_msc/src/msc_disk.c
index d325d77fa..9645f4bfc 100644
--- a/examples/device/cdc_msc/src/msc_disk.c
+++ b/examples/device/cdc_msc/src/msc_disk.c
@@ -40,17 +40,15 @@ static bool ejected = false;
 If you find any bugs or get any questions, feel free to file an\r\n\
 issue at github.com/hathach/tinyusb"
 
-enum
-{
-  DISK_BLOCK_NUM  = 16, // 8KB is the smallest size that windows allow to mount
+enum {
+  DISK_BLOCK_NUM = 16,// 8KB is the smallest size that windows allow to mount
   DISK_BLOCK_SIZE = 512
 };
 
 #ifdef CFG_EXAMPLE_MSC_READONLY
 const
 #endif
-uint8_t msc_disk[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
-{
+uint8_t msc_disk[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] = {
   //------------- Block0: Boot Sector -------------//
   // byte_per_sector    = DISK_BLOCK_SIZE; fat12_sector_num_16  = DISK_BLOCK_NUM;
   // sector_per_cluster = 1; reserved_sectors = 1;
@@ -59,60 +57,59 @@ uint8_t msc_disk[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
   // drive_number       = 0x80; media_type = 0xf8; extended_boot_signature = 0x29;
   // filesystem_type    = "FAT12   "; volume_serial_number = 0x1234; volume_label = "TinyUSB MSC";
   // FAT magic code at offset 510-511
-  {
-      0xEB, 0x3C, 0x90, 0x4D, 0x53, 0x44, 0x4F, 0x53, 0x35, 0x2E, 0x30, 0x00, 0x02, 0x01, 0x01, 0x00,
-      0x01, 0x10, 0x00, 0x10, 0x00, 0xF8, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x80, 0x00, 0x29, 0x34, 0x12, 0x00, 0x00, 'T' , 'i' , 'n' , 'y' , 'U' ,
-      'S' , 'B' , ' ' , 'M' , 'S' , 'C' , 0x46, 0x41, 0x54, 0x31, 0x32, 0x20, 0x20, 0x20, 0x00, 0x00,
+{
+    0xEB, 0x3C, 0x90, 0x4D, 0x53, 0x44, 0x4F, 0x53, 0x35, 0x2E, 0x30, 0x00, 0x02, 0x01, 0x01, 0x00,
+    0x01, 0x10, 0x00, 0x10, 0x00, 0xF8, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x80, 0x00, 0x29, 0x34, 0x12, 0x00, 0x00, 'T', 'i', 'n', 'y', 'U',
+    'S', 'B', ' ', 'M', 'S', 'C', 0x46, 0x41, 0x54, 0x31, 0x32, 0x20, 0x20, 0x20, 0x00, 0x00,
 
-      // Zero up to 2 last bytes of FAT magic code
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    // Zero up to 2 last bytes of FAT magic code
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0xAA
-  },
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0xAA},
 
   //------------- Block1: FAT12 Table -------------//
-  {
-      0xF8, 0xFF, 0xFF, 0xFF, 0x0F // // first 2 entries must be F8FF, third entry is cluster end of readme file
+{
+      0xF8, 0xFF, 0xFF, 0xFF, 0x0F// // first 2 entries must be F8FF, third entry is cluster end of readme file
   },
 
   //------------- Block2: Root Directory -------------//
-  {
-      // first entry is volume label
-      'T' , 'i' , 'n' , 'y' , 'U' , 'S' , 'B' , ' ' , 'M' , 'S' , 'C' , 0x08, 0x00, 0x00, 0x00, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4F, 0x6D, 0x65, 0x43, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      // second entry is readme file
-      'R' , 'E' , 'A' , 'D' , 'M' , 'E' , ' ' , ' ' , 'T' , 'X' , 'T' , 0x20, 0x00, 0xC6, 0x52, 0x6D,
-      0x65, 0x43, 0x65, 0x43, 0x00, 0x00, 0x88, 0x6D, 0x65, 0x43, 0x02, 0x00,
-      sizeof(README_CONTENTS)-1, 0x00, 0x00, 0x00 // readme's files size (4 Bytes)
+{
+    // first entry is volume label
+    'T', 'i', 'n', 'y', 'U', 'S', 'B', ' ', 'M', 'S', 'C', 0x08, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4F, 0x6D, 0x65, 0x43, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    // second entry is readme file
+    'R', 'E', 'A', 'D', 'M', 'E', ' ', ' ', 'T', 'X', 'T', 0x20, 0x00, 0xC6, 0x52, 0x6D,
+    0x65, 0x43, 0x65, 0x43, 0x00, 0x00, 0x88, 0x6D, 0x65, 0x43, 0x02, 0x00,
+    sizeof(README_CONTENTS) - 1, 0x00, 0x00, 0x00// readme's files size (4 Bytes)
   },
 
   //------------- Block3: Readme Content -------------//
@@ -121,23 +118,21 @@ uint8_t msc_disk[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
 
 // Invoked when received SCSI_CMD_INQUIRY
 // Application fill vendor id, product id and revision with string up to 8, 16, 4 characters respectively
-void tud_msc_inquiry_cb(uint8_t lun, uint8_t vendor_id[8], uint8_t product_id[16], uint8_t product_rev[4])
-{
+void tud_msc_inquiry_cb(uint8_t lun, uint8_t vendor_id[8], uint8_t product_id[16], uint8_t product_rev[4]) {
   (void) lun;
 
   const char vid[] = "TinyUSB";
   const char pid[] = "Mass Storage";
   const char rev[] = "1.0";
 
-  memcpy(vendor_id  , vid, strlen(vid));
-  memcpy(product_id , pid, strlen(pid));
+  memcpy(vendor_id, vid, strlen(vid));
+  memcpy(product_id, pid, strlen(pid));
   memcpy(product_rev, rev, strlen(rev));
 }
 
 // Invoked when received Test Unit Ready command.
 // return true allowing host to read/write this LUN e.g SD card inserted
-bool tud_msc_test_unit_ready_cb(uint8_t lun)
-{
+bool tud_msc_test_unit_ready_cb(uint8_t lun) {
   (void) lun;
 
   // RAM disk is ready until ejected
@@ -152,29 +147,24 @@ bool tud_msc_test_unit_ready_cb(uint8_t lun)
 
 // Invoked when received SCSI_CMD_READ_CAPACITY_10 and SCSI_CMD_READ_FORMAT_CAPACITY to determine the disk size
 // Application update block count and block size
-void tud_msc_capacity_cb(uint8_t lun, uint32_t* block_count, uint16_t* block_size)
-{
+void tud_msc_capacity_cb(uint8_t lun, uint32_t *block_count, uint16_t *block_size) {
   (void) lun;
 
   *block_count = DISK_BLOCK_NUM;
-  *block_size  = DISK_BLOCK_SIZE;
+  *block_size = DISK_BLOCK_SIZE;
 }
 
 // Invoked when received Start Stop Unit command
 // - Start = 0 : stopped power mode, if load_eject = 1 : unload disk storage
 // - Start = 1 : active mode, if load_eject = 1 : load disk storage
-bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, bool load_eject)
-{
+bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, bool load_eject) {
   (void) lun;
   (void) power_condition;
 
-  if ( load_eject )
-  {
-    if (start)
-    {
+  if (load_eject) {
+    if (start) {
       // load disk storage
-    }else
-    {
+    } else {
       // unload disk storage
       ejected = true;
     }
@@ -185,52 +175,51 @@ bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, boo
 
 // Callback invoked when received READ10 command.
 // Copy disk's data to buffer (up to bufsize) and return number of copied bytes.
-int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void* buffer, uint32_t bufsize)
-{
+int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void *buffer, uint32_t bufsize) {
   (void) lun;
 
   // out of ramdisk
-  if ( lba >= DISK_BLOCK_NUM ) {
+  if (lba >= DISK_BLOCK_NUM) {
     return -1;
   }
 
   // Check for overflow of offset + bufsize
-  if ( offset + bufsize > DISK_BLOCK_SIZE ) {
+  if (offset + bufsize > DISK_BLOCK_SIZE) {
     return -1;
   }
 
-  uint8_t const* addr = msc_disk[lba] + offset;
+  uint8_t const *addr = msc_disk[lba] + offset;
   memcpy(buffer, addr, bufsize);
 
   return (int32_t) bufsize;
 }
 
-bool tud_msc_is_writable_cb (uint8_t lun)
-{
+bool tud_msc_is_writable_cb(uint8_t lun) {
   (void) lun;
 
-#ifdef CFG_EXAMPLE_MSC_READONLY
+  #ifdef CFG_EXAMPLE_MSC_READONLY
   return false;
-#else
+  #else
   return true;
-#endif
+  #endif
 }
 
 // Callback invoked when received WRITE10 command.
 // Process data in buffer to disk's storage and return number of written bytes
-int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t* buffer, uint32_t bufsize)
-{
+int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t *buffer, uint32_t bufsize) {
   (void) lun;
 
   // out of ramdisk
-  if ( lba >= DISK_BLOCK_NUM ) return -1;
+  if (lba >= DISK_BLOCK_NUM) return -1;
 
-#ifndef CFG_EXAMPLE_MSC_READONLY
-  uint8_t* addr = msc_disk[lba] + offset;
+  #ifndef CFG_EXAMPLE_MSC_READONLY
+  uint8_t *addr = msc_disk[lba] + offset;
   memcpy(addr, buffer, bufsize);
-#else
-  (void) lba; (void) offset; (void) buffer;
-#endif
+  #else
+  (void) lba;
+  (void) offset;
+  (void) buffer;
+  #endif
 
   return (int32_t) bufsize;
 }
@@ -238,42 +227,18 @@ int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t*
 // Callback invoked when received an SCSI command not in built-in list below
 // - READ_CAPACITY10, READ_FORMAT_CAPACITY, INQUIRY, MODE_SENSE6, REQUEST_SENSE
 // - READ10 and WRITE10 has their own callbacks
-int32_t tud_msc_scsi_cb (uint8_t lun, uint8_t const scsi_cmd[16], void* buffer, uint16_t bufsize)
-{
-  // read10 & write10 has their own callback and MUST not be handled here
+int32_t tud_msc_scsi_cb(uint8_t lun, uint8_t const scsi_cmd[16], void *buffer, uint16_t bufsize) {
+  (void) buffer;
+  (void) bufsize;
 
-  void const* response = NULL;
-  int32_t resplen = 0;
-
-  // most scsi handled is input
-  bool in_xfer = true;
-
-  switch (scsi_cmd[0])
-  {
+  switch (scsi_cmd[0]) {
     default:
       // Set Sense = Invalid Command Operation
       tud_msc_set_sense(lun, SCSI_SENSE_ILLEGAL_REQUEST, 0x20, 0x00);
 
       // negative means error -> tinyusb could stall and/or response with failed status
-      resplen = -1;
-    break;
+      return -1;
   }
-
-  // return resplen must not larger than bufsize
-  if ( resplen > bufsize ) resplen = bufsize;
-
-  if ( response && (resplen > 0) )
-  {
-    if(in_xfer)
-    {
-      memcpy(buffer, response, (size_t) resplen);
-    }else
-    {
-      // SCSI output
-    }
-  }
-
-  return (int32_t) resplen;
 }
 
 #endif
diff --git a/examples/device/msc_dual_lun/src/msc_disk_dual.c b/examples/device/msc_dual_lun/src/msc_disk_dual.c
index b44b77c6c..1f7fb98c7 100644
--- a/examples/device/msc_dual_lun/src/msc_disk_dual.c
+++ b/examples/device/msc_dual_lun/src/msc_disk_dual.c
@@ -55,8 +55,7 @@ If you find any bugs or get any questions, feel free to file an\r\n\
 issue at github.com/hathach/tinyusb"
 
 
-MSC_CONST uint8_t msc_disk0[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
-{
+MSC_CONST uint8_t msc_disk0[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] = {
   //------------- Block0: Boot Sector -------------//
   // byte_per_sector    = DISK_BLOCK_SIZE; fat12_sector_num_16  = DISK_BLOCK_NUM;
   // sector_per_cluster = 1; reserved_sectors = 1;
@@ -283,9 +282,11 @@ bool tud_msc_is_writable_cb(uint8_t lun) {
 // Process data in buffer to disk's storage and return number of written bytes
 int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t* buffer, uint32_t bufsize) {
   // out of ramdisk
-  if (lba >= DISK_BLOCK_NUM) return -1;
+  if (lba >= DISK_BLOCK_NUM) {
+    return -1;
+  }
 
-#if defined(CFG_EXAMPLE_MSC_READONLY) || defined(CFG_EXAMPLE_MSC_DUAL_READONLY)
+  #if defined(CFG_EXAMPLE_MSC_READONLY) || defined(CFG_EXAMPLE_MSC_DUAL_READONLY)
   (void) lun;
   (void) lba;
   (void) offset;
@@ -302,11 +303,8 @@ int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t*
 // - READ_CAPACITY10, READ_FORMAT_CAPACITY, INQUIRY, MODE_SENSE6, REQUEST_SENSE
 // - READ10 and WRITE10 has their own callbacks (MUST not be handled here)
 int32_t tud_msc_scsi_cb(uint8_t lun, uint8_t const scsi_cmd[16], void* buffer, uint16_t bufsize) {
-  void const* response = NULL;
-  int32_t resplen = 0;
-
-  // most scsi handled is input
-  bool in_xfer = true;
+  (void) buffer;
+  (void) bufsize;
 
   switch (scsi_cmd[0]) {
     default:
@@ -316,19 +314,6 @@ int32_t tud_msc_scsi_cb(uint8_t lun, uint8_t const scsi_cmd[16], void* buffer, u
       // negative means error -> tinyusb could stall and/or response with failed status
       return -1;
   }
-
-  // return resplen must not larger than bufsize
-  if (resplen > bufsize) resplen = bufsize;
-
-  if (response && (resplen > 0)) {
-    if (in_xfer) {
-      memcpy(buffer, response, (size_t) resplen);
-    } else {
-      // SCSI output
-    }
-  }
-
-  return resplen;
 }
 
 #endif
diff --git a/hw/bsp/stm32f2/boards/stm32f207nucleo/board.mk b/hw/bsp/stm32f2/boards/stm32f207nucleo/board.mk
index ba185d199..6e681ef57 100644
--- a/hw/bsp/stm32f2/boards/stm32f207nucleo/board.mk
+++ b/hw/bsp/stm32f2/boards/stm32f207nucleo/board.mk
@@ -1,12 +1,9 @@
-CFLAGS += \
-  -DSTM32F207xx \
+MCU_VARIANT = stm32f207xx
+CFLAGS += -DSTM32F207xx
 
 # All source paths should be relative to the top level.
 LD_FILE = $(BOARD_PATH)/STM32F207ZGTx_FLASH.ld
 
-SRC_S += \
-  $(ST_CMSIS)/Source/Templates/gcc/startup_stm32f207xx.s
-
 # For flash-jlink target
 JLINK_DEVICE = stm32f207zg
 
diff --git a/hw/bsp/stm32f2/family.mk b/hw/bsp/stm32f2/family.mk
index 7af9a76a0..e8f02548d 100644
--- a/hw/bsp/stm32f2/family.mk
+++ b/hw/bsp/stm32f2/family.mk
@@ -1,5 +1,4 @@
 ST_FAMILY = f2
-
 ST_CMSIS = hw/mcu/st/cmsis_device_$(ST_FAMILY)
 ST_HAL_DRIVER = hw/mcu/st/stm32$(ST_FAMILY)xx_hal_driver
 
@@ -14,11 +13,10 @@ CPU_CORE ?= cortex-m3
 CFLAGS += \
 	-DCFG_TUSB_MCU=OPT_MCU_STM32F2
 
+# mcu driver cause following warnings
 CFLAGS_GCC += \
   -flto \
-
-# mcu driver cause following warnings
-CFLAGS_GCC += -Wno-error=sign-compare
+  -Wno-error=sign-compare
 
 LDFLAGS_GCC += \
   -nostdlib -nostartfiles \
@@ -40,3 +38,10 @@ INC += \
   $(TOP)/$(ST_CMSIS)/Include \
   $(TOP)/$(ST_HAL_DRIVER)/Inc \
   $(TOP)/$(BOARD_PATH)
+
+# Startup
+SRC_S_GCC += $(ST_CMSIS)/Source/Templates/gcc/startup_${MCU_VARIANT}.s
+SRC_S_IAR += $(ST_CMSIS)/Source/Templates/iar/startup_${MCU_VARIANT}.s
+
+# Linker
+LD_FILE_IAR ?= $(ST_CMSIS)/Source/Templates/iar/linker/${MCU_VARIANT}_flash.icf
diff --git a/hw/bsp/stm32f3/boards/stm32f303disco/board.mk b/hw/bsp/stm32f3/boards/stm32f303disco/board.mk
index e387f2d54..6b9a3e283 100644
--- a/hw/bsp/stm32f3/boards/stm32f303disco/board.mk
+++ b/hw/bsp/stm32f3/boards/stm32f303disco/board.mk
@@ -1,12 +1,10 @@
+MCU_VARIANT = stm32f303xc
 CFLAGS += \
   -DSTM32F303xC \
 
 # All source paths should be relative to the top level.
 LD_FILE = $(BOARD_PATH)/STM32F303VCTx_FLASH.ld
 
-SRC_S += \
-  $(ST_CMSIS)/Source/Templates/gcc/startup_stm32f303xc.s
-
 # For flash-jlink target
 JLINK_DEVICE = stm32f303vc
 
diff --git a/hw/bsp/stm32f3/family.mk b/hw/bsp/stm32f3/family.mk
index 4fe3aa99d..13734583a 100644
--- a/hw/bsp/stm32f3/family.mk
+++ b/hw/bsp/stm32f3/family.mk
@@ -1,22 +1,17 @@
 ST_FAMILY = f3
-
 ST_CMSIS = hw/mcu/st/cmsis_device_$(ST_FAMILY)
 ST_HAL_DRIVER = hw/mcu/st/stm32$(ST_FAMILY)xx_hal_driver
 
-DEPS_SUBMODULES += \
-	lib/CMSIS_5 \
-	$(ST_CMSIS) \
-	$(ST_HAL_DRIVER)
-
 include $(TOP)/$(BOARD_PATH)/board.mk
 CPU_CORE ?= cortex-m4
 
 CFLAGS += \
-  -flto \
   -DCFG_TUSB_MCU=OPT_MCU_STM32F3
 
 # mcu driver cause following warnings
-CFLAGS += -Wno-error=unused-parameter
+CFLAGS_GCC += \
+  -flto \
+  -Wno-error=unused-parameter
 
 LDFLAGS_GCC += \
   -nostdlib -nostartfiles \
@@ -36,3 +31,10 @@ INC += \
   $(TOP)/$(ST_CMSIS)/Include \
   $(TOP)/$(ST_HAL_DRIVER)/Inc \
   $(TOP)/$(BOARD_PATH)
+
+# Startup
+SRC_S_GCC += $(ST_CMSIS)/Source/Templates/gcc/startup_${MCU_VARIANT}.s
+SRC_S_IAR += $(ST_CMSIS)/Source/Templates/iar/startup_${MCU_VARIANT}.s
+
+# Linker
+LD_FILE_IAR ?= $(ST_CMSIS)/Source/Templates/iar/linker/${MCU_VARIANT}_flash.icf
diff --git a/hw/bsp/stm32l0/boards/stm32l052dap52/board.mk b/hw/bsp/stm32l0/boards/stm32l052dap52/board.mk
index 0b1348474..e63b41f12 100644
--- a/hw/bsp/stm32l0/boards/stm32l052dap52/board.mk
+++ b/hw/bsp/stm32l0/boards/stm32l052dap52/board.mk
@@ -1,10 +1,9 @@
+MCU_VARIANT = stm32l052xx
 CFLAGS += \
 	-DSTM32L052xx
 
 LD_FILE = $(BOARD_PATH)/STM32L052K8Ux_FLASH.ld
 
-SRC_S += $(ST_CMSIS)/Source/Templates/gcc/startup_stm32l052xx.s
-
 # For flash-jlink target
 JLINK_DEVICE = stm32l052k8
 
diff --git a/hw/bsp/stm32l0/boards/stm32l0538disco/board.mk b/hw/bsp/stm32l0/boards/stm32l0538disco/board.mk
index deed519ba..f3e6978b0 100644
--- a/hw/bsp/stm32l0/boards/stm32l0538disco/board.mk
+++ b/hw/bsp/stm32l0/boards/stm32l0538disco/board.mk
@@ -1,12 +1,10 @@
+MCU_VARIANT = stm32l053xx
 CFLAGS += \
   -DSTM32L053xx
 
 # All source paths should be relative to the top level.
 LD_FILE = $(BOARD_PATH)/STM32L053C8Tx_FLASH.ld
 
-SRC_S += \
-  $(ST_CMSIS)/Source/Templates/gcc/startup_stm32l053xx.s
-
 # For flash-jlink target
 JLINK_DEVICE = STM32L053R8
 
diff --git a/hw/bsp/stm32l0/family.mk b/hw/bsp/stm32l0/family.mk
index fe7561fc2..921b1b413 100644
--- a/hw/bsp/stm32l0/family.mk
+++ b/hw/bsp/stm32l0/family.mk
@@ -1,9 +1,4 @@
 ST_FAMILY = l0
-DEPS_SUBMODULES += \
-	lib/CMSIS_5 \
-	hw/mcu/st/cmsis_device_$(ST_FAMILY) \
-	hw/mcu/st/stm32$(ST_FAMILY)xx_hal_driver
-
 ST_CMSIS = hw/mcu/st/cmsis_device_$(ST_FAMILY)
 ST_HAL_DRIVER = hw/mcu/st/stm32$(ST_FAMILY)xx_hal_driver
 
@@ -11,20 +6,17 @@ include $(TOP)/$(BOARD_PATH)/board.mk
 CPU_CORE ?= cortex-m0plus
 
 CFLAGS += \
-  -flto \
   -DCFG_EXAMPLE_MSC_READONLY \
   -DCFG_EXAMPLE_VIDEO_READONLY \
   -DCFG_TUSB_MCU=OPT_MCU_STM32L0
 
 # mcu driver cause following warnings
 CFLAGS_GCC += \
+  -flto \
 	-Wno-error=unused-parameter \
 	-Wno-error=redundant-decls \
 	-Wno-error=cast-align \
-
-ifeq ($(TOOLCHAIN),gcc)
-CFLAGS_GCC += -Wno-error=maybe-uninitialized
-endif
+	-Wno-error=maybe-uninitialized \
 
 CFLAGS_CLANG += \
   -Wno-error=parentheses-equality
@@ -48,3 +40,10 @@ INC += \
   $(TOP)/lib/CMSIS_5/CMSIS/Core/Include \
   $(TOP)/$(ST_CMSIS)/Include \
   $(TOP)/$(ST_HAL_DRIVER)/Inc
+
+# Startup
+SRC_S_GCC += $(ST_CMSIS)/Source/Templates/gcc/startup_${MCU_VARIANT}.s
+SRC_S_IAR += $(ST_CMSIS)/Source/Templates/iar/startup_${MCU_VARIANT}.s
+
+# Linker
+LD_FILE_IAR ?= $(ST_CMSIS)/Source/Templates/iar/linker/$(MCU_VARIANT)_flash.icf