Merge branch 'master' into xfer_close

Signed-off-by: HiFiPhile <[email protected]>

17 files changed, 304 insertions, 381 deletions

diff --git a/examples/build_system/cmake/cpu/cortex-m0.cmake b/examples/build_system/cmake/cpu/cortex-m0.cmake
index 62019d90d..f837c7eb8 100644
--- a/examples/build_system/cmake/cpu/cortex-m0.cmake
+++ b/examples/build_system/cmake/cpu/cortex-m0.cmake
@@ -1,7 +1,7 @@
 if (TOOLCHAIN STREQUAL "gcc")
   set(TOOLCHAIN_COMMON_FLAGS
     -mthumb
-    -mcpu=cortex-m0plus
+    -mcpu=cortex-m0
     -mfloat-abi=soft
     )
   set(FREERTOS_PORT GCC_ARM_CM0 CACHE INTERNAL "")
diff --git a/examples/build_system/make/cpu/cortex-m4.mk b/examples/build_system/make/cpu/cortex-m4.mk
index 4e16819d1..57d6e126d 100644
--- a/examples/build_system/make/cpu/cortex-m4.mk
+++ b/examples/build_system/make/cpu/cortex-m4.mk
@@ -12,8 +12,8 @@ else ifeq ($(TOOLCHAIN),clang)
 	  -mfpu=fpv4-sp-d16 \
 
 else ifeq ($(TOOLCHAIN),iar)
-  CFLAGS += --cpu cortex-m4 --fpu VFPv4
-  ASFLAGS += --cpu cortex-m4 --fpu VFPv4
+  CFLAGS += --cpu cortex-m4 --fpu VFPv4-SP
+  ASFLAGS += --cpu cortex-m4 --fpu VFPv4-SP
 
 else
   $(error "TOOLCHAIN is not supported")
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
-
-  void const* response = NULL;
-  int32_t resplen = 0;
+int32_t tud_msc_scsi_cb(uint8_t lun, uint8_t const scsi_cmd[16], void *buffer, uint16_t bufsize) {
+  (void) buffer;
+  (void) bufsize;
 
-  // 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 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 -1;
   }
-
-  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/examples/dual/host_info_to_device_cdc/src/main.c b/examples/dual/host_info_to_device_cdc/src/main.c
index 668808db2..7e593f234 100644
--- a/examples/dual/host_info_to_device_cdc/src/main.c
+++ b/examples/dual/host_info_to_device_cdc/src/main.c
@@ -70,8 +70,11 @@ enum {
 static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
 
 static bool is_print[CFG_TUH_DEVICE_MAX+1] = { 0 };
+static tusb_desc_device_t descriptor_device[CFG_TUH_DEVICE_MAX+1];
 
 static void print_utf16(uint16_t *temp_buf, size_t buf_len);
+static void print_device_info(uint8_t daddr, const tusb_desc_device_t* desc_device);
+
 void led_blinking_task(void);
 void cdc_task(void);
 
@@ -135,33 +138,52 @@ void tud_resume_cb(void) {
   blink_interval_ms = tud_mounted() ? BLINK_MOUNTED : BLINK_NOT_MOUNTED;
 }
 
-#if 1
+void cdc_task(void) {
+  if (!tud_cdc_connected()) {
+    // delay a bit otherwise we can outpace host's terminal. Linux will set LineState (DTR) then Line Coding.
+    // If we send data before Linux's terminal set Line Coding, it can be ignored --> missing data with hardware test loop
+    board_delay(20);
+    return;
+  }
+
+  for (uint8_t daddr = 1; daddr <= CFG_TUH_DEVICE_MAX; daddr++) {
+    if (tuh_mounted(daddr)) {
+      if (is_print[daddr]) {
+        is_print[daddr] = false;
+        print_device_info(daddr, &descriptor_device[daddr]);
+        tud_cdc_write_flush();
+      }
+    }
+  }
+}
+
+//--------------------------------------------------------------------+
+// Host Get device information
+//--------------------------------------------------------------------+
 #define cdc_printf(...)                          \
   do {                                           \
     char _tempbuf[256];                          \
-    int count = sprintf(_tempbuf, __VA_ARGS__);  \
-    tud_cdc_write(_tempbuf, (uint32_t) count);   \
-    tud_cdc_write_flush();                       \
-    tud_task();                                  \
+    char* _bufptr = _tempbuf;                        \
+    uint32_t count = (uint32_t) sprintf(_tempbuf, __VA_ARGS__);  \
+    while (count > 0) { \
+        uint32_t wr_count = tud_cdc_write(_bufptr, count); \
+        count -= wr_count; \
+        _bufptr += wr_count; \
+        if (count > 0){ \
+          tud_task();\
+          tud_cdc_write_flush(); \
+        } \
+    } \
   } while(0)
-#endif
-
-//#define cdc_printf printf
-
-void print_device_info(uint8_t daddr) {
-  tusb_desc_device_t desc_device;
-  uint8_t xfer_result = tuh_descriptor_get_device_sync(daddr, &desc_device, 18);
-  if (XFER_RESULT_SUCCESS != xfer_result) {
-    tud_cdc_write_str("Failed to get device descriptor\r\n");
-    return;
-  }
 
+static void print_device_info(uint8_t daddr, const tusb_desc_device_t* desc_device) {
   // Get String descriptor using Sync API
   uint16_t serial[64];
   uint16_t buf[128];
+  (void) buf;
 
-  cdc_printf("Device %u: ID %04x:%04x SN ", daddr, desc_device.idVendor, desc_device.idProduct);
-  xfer_result = tuh_descriptor_get_serial_string_sync(daddr, LANGUAGE_ID, serial, sizeof(serial));
+  cdc_printf("Device %u: ID %04x:%04x SN ", daddr, desc_device->idVendor, desc_device->idProduct);
+  uint8_t xfer_result = tuh_descriptor_get_serial_string_sync(daddr, LANGUAGE_ID, serial, sizeof(serial));
   if (XFER_RESULT_SUCCESS != xfer_result) {
     serial[0] = 'n';
     serial[1] = '/';
@@ -169,58 +191,46 @@ void print_device_info(uint8_t daddr) {
     serial[3] = 0;
   }
   print_utf16(serial, TU_ARRAY_SIZE(serial));
-  tud_cdc_write_str("\r\n");
+  cdc_printf("\r\n");
 
   cdc_printf("Device Descriptor:\r\n");
-  cdc_printf("  bLength             %u\r\n"     , desc_device.bLength);
-  cdc_printf("  bDescriptorType     %u\r\n"     , desc_device.bDescriptorType);
-  cdc_printf("  bcdUSB              %04x\r\n"   , desc_device.bcdUSB);
-  cdc_printf("  bDeviceClass        %u\r\n"     , desc_device.bDeviceClass);
-  cdc_printf("  bDeviceSubClass     %u\r\n"     , desc_device.bDeviceSubClass);
-  cdc_printf("  bDeviceProtocol     %u\r\n"     , desc_device.bDeviceProtocol);
-  cdc_printf("  bMaxPacketSize0     %u\r\n"     , desc_device.bMaxPacketSize0);
-  cdc_printf("  idVendor            0x%04x\r\n" , desc_device.idVendor);
-  cdc_printf("  idProduct           0x%04x\r\n" , desc_device.idProduct);
-  cdc_printf("  bcdDevice           %04x\r\n"   , desc_device.bcdDevice);
+  cdc_printf("  bLength             %u\r\n"     , desc_device->bLength);
+  cdc_printf("  bDescriptorType     %u\r\n"     , desc_device->bDescriptorType);
+  cdc_printf("  bcdUSB              %04x\r\n"   , desc_device->bcdUSB);
+  cdc_printf("  bDeviceClass        %u\r\n"     , desc_device->bDeviceClass);
+  cdc_printf("  bDeviceSubClass     %u\r\n"     , desc_device->bDeviceSubClass);
+  cdc_printf("  bDeviceProtocol     %u\r\n"     , desc_device->bDeviceProtocol);
+  cdc_printf("  bMaxPacketSize0     %u\r\n"     , desc_device->bMaxPacketSize0);
+  cdc_printf("  idVendor            0x%04x\r\n" , desc_device->idVendor);
+  cdc_printf("  idProduct           0x%04x\r\n" , desc_device->idProduct);
+  cdc_printf("  bcdDevice           %04x\r\n"   , desc_device->bcdDevice);
 
-  cdc_printf("  iManufacturer       %u     "     , desc_device.iManufacturer);
+  cdc_printf("  iManufacturer       %u     "     , desc_device->iManufacturer);
   xfer_result = tuh_descriptor_get_manufacturer_string_sync(daddr, LANGUAGE_ID, buf, sizeof(buf));
-  if (XFER_RESULT_SUCCESS == xfer_result ) {
+  if (XFER_RESULT_SUCCESS == xfer_result) {
     print_utf16(buf, TU_ARRAY_SIZE(buf));
   }
-  tud_cdc_write_str("\r\n");
+  cdc_printf("\r\n");
 
-  cdc_printf("  iProduct            %u     "     , desc_device.iProduct);
+  cdc_printf("  iProduct            %u     "     , desc_device->iProduct);
   xfer_result = tuh_descriptor_get_product_string_sync(daddr, LANGUAGE_ID, buf, sizeof(buf));
   if (XFER_RESULT_SUCCESS == xfer_result) {
     print_utf16(buf, TU_ARRAY_SIZE(buf));
   }
-  tud_cdc_write_str("\r\n");
+  cdc_printf("\r\n");
 
-  cdc_printf("  iSerialNumber       %u     "     , desc_device.iSerialNumber);
-  tud_cdc_write_str((char*)serial); // serial is already to UTF-8
-  tud_cdc_write_str("\r\n");
+  cdc_printf("  iSerialNumber       %u     "     , desc_device->iSerialNumber);
+  cdc_printf((char*)serial); // serial is already to UTF-8
+  cdc_printf("\r\n");
 
-  cdc_printf("  bNumConfigurations  %u\r\n"     , desc_device.bNumConfigurations);
+  cdc_printf("  bNumConfigurations  %u\r\n"     , desc_device->bNumConfigurations);
 }
 
-void cdc_task(void) {
-  if (tud_cdc_connected()) {
-    for (uint8_t daddr = 1; daddr <= CFG_TUH_DEVICE_MAX; daddr++) {
-      if (tuh_mounted(daddr)) {
-        if (is_print[daddr]) {
-          is_print[daddr] = false;
-          print_device_info(daddr);
-          tud_cdc_write_flush();
-        }
-      }
-    }
-  }
+void tuh_enum_descriptor_device_cb(uint8_t daddr, tusb_desc_device_t const* desc_device) {
+  (void) daddr;
+  descriptor_device[daddr] = *desc_device; // save device descriptor
 }
 
-//--------------------------------------------------------------------+
-// Host Get device information
-//--------------------------------------------------------------------+
 void tuh_mount_cb(uint8_t daddr) {
   printf("mounted device %u\r\n", daddr);
   is_print[daddr] = true;
@@ -296,7 +306,5 @@ static void print_utf16(uint16_t *temp_buf, size_t buf_len) {
   _convert_utf16le_to_utf8(temp_buf + 1, utf16_len, (uint8_t *) temp_buf, sizeof(uint16_t) * buf_len);
   ((uint8_t*) temp_buf)[utf8_len] = '\0';
 
-  tud_cdc_write(temp_buf, utf8_len);
-  tud_cdc_write_flush();
-  tud_task();
+  cdc_printf((char*) temp_buf);
 }
diff --git a/examples/host/bare_api/src/main.c b/examples/host/bare_api/src/main.c
index f582f4f5a..0c76ff0c9 100644
--- a/examples/host/bare_api/src/main.c
+++ b/examples/host/bare_api/src/main.c
@@ -55,16 +55,15 @@ uint8_t* get_hid_buf(uint8_t daddr);
 void free_hid_buf(uint8_t daddr);
 
 /*------------- MAIN -------------*/
-int main(void)
-{
+int main(void) {
   board_init();
 
   printf("TinyUSB Bare API Example\r\n");
 
   // init host stack on configured roothub port
   tusb_rhport_init_t host_init = {
-    .role = TUSB_ROLE_HOST,
-    .speed = TUSB_SPEED_AUTO
+      .role = TUSB_ROLE_HOST,
+      .speed = TUSB_SPEED_AUTO
   };
   tusb_init(BOARD_TUH_RHPORT, &host_init);
 
@@ -72,8 +71,7 @@ int main(void)
     board_init_after_tusb();
   }
 
-  while (1)
-  {
+  while (1) {
     // tinyusb host task
     tuh_task();
     led_blinking_task();
@@ -85,8 +83,7 @@ int main(void)
 /*------------- TinyUSB Callbacks -------------*/
 
 // Invoked when device is mounted (configured)
-void tuh_mount_cb (uint8_t daddr)
-{
+void tuh_mount_cb(uint8_t daddr) {
   printf("Device attached, address = %d\r\n", daddr);
 
   // Get Device Descriptor
@@ -95,8 +92,7 @@ void tuh_mount_cb (uint8_t daddr)
 }
 
 /// Invoked when device is unmounted (bus reset/unplugged)
-void tuh_umount_cb(uint8_t daddr)
-{
+void tuh_umount_cb(uint8_t daddr) {
   printf("Device removed, address = %d\r\n", daddr);
   free_hid_buf(daddr);
 }
@@ -104,11 +100,8 @@ void tuh_umount_cb(uint8_t daddr)
 //--------------------------------------------------------------------+
 // Device Descriptor
 //--------------------------------------------------------------------+
-
-void print_device_descriptor(tuh_xfer_t* xfer)
-{
-  if ( XFER_RESULT_SUCCESS != xfer->result )
-  {
+void print_device_descriptor(tuh_xfer_t *xfer) {
+  if (XFER_RESULT_SUCCESS != xfer->result) {
     printf("Failed to get device descriptor\r\n");
     return;
   }
@@ -131,33 +124,29 @@ void print_device_descriptor(tuh_xfer_t* xfer)
   // Get String descriptor using Sync API
   uint16_t temp_buf[128];
 
-  printf("  iManufacturer       %u     "     , desc_device.iManufacturer);
-  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_manufacturer_string_sync(daddr, LANGUAGE_ID, temp_buf, sizeof(temp_buf)) )
-  {
+  printf("  iManufacturer       %u     ", desc_device.iManufacturer);
+  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_manufacturer_string_sync(daddr, LANGUAGE_ID, temp_buf, sizeof(temp_buf))) {
     print_utf16(temp_buf, TU_ARRAY_SIZE(temp_buf));
   }
   printf("\r\n");
 
-  printf("  iProduct            %u     "     , desc_device.iProduct);
-  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_product_string_sync(daddr, LANGUAGE_ID, temp_buf, sizeof(temp_buf)))
-  {
+  printf("  iProduct            %u     ", desc_device.iProduct);
+  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_product_string_sync(daddr, LANGUAGE_ID, temp_buf, sizeof(temp_buf))) {
     print_utf16(temp_buf, TU_ARRAY_SIZE(temp_buf));
   }
   printf("\r\n");
 
-  printf("  iSerialNumber       %u     "     , desc_device.iSerialNumber);
-  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_serial_string_sync(daddr, LANGUAGE_ID, temp_buf, sizeof(temp_buf)))
-  {
+  printf("  iSerialNumber       %u     ", desc_device.iSerialNumber);
+  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_serial_string_sync(daddr, LANGUAGE_ID, temp_buf, sizeof(temp_buf))) {
     print_utf16(temp_buf, TU_ARRAY_SIZE(temp_buf));
   }
   printf("\r\n");
 
-  printf("  bNumConfigurations  %u\r\n"     , desc_device.bNumConfigurations);
+  printf("  bNumConfigurations  %u\r\n", desc_device.bNumConfigurations);
 
   // Get configuration descriptor with sync API
-  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_configuration_sync(daddr, 0, temp_buf, sizeof(temp_buf)))
-  {
-    parse_config_descriptor(daddr, (tusb_desc_configuration_t*) temp_buf);
+  if (XFER_RESULT_SUCCESS == tuh_descriptor_get_configuration_sync(daddr, 0, temp_buf, sizeof(temp_buf))) {
+    parse_config_descriptor(daddr, (tusb_desc_configuration_t *) temp_buf);
   }
 }
 
@@ -171,37 +160,33 @@ uint16_t count_interface_total_len(tusb_desc_interface_t const* desc_itf, uint8_
 void open_hid_interface(uint8_t daddr, tusb_desc_interface_t const *desc_itf, uint16_t max_len);
 
 // simple configuration parser to open and listen to HID Endpoint IN
-void parse_config_descriptor(uint8_t dev_addr, tusb_desc_configuration_t const* desc_cfg)
-{
-  uint8_t const* desc_end = ((uint8_t const*) desc_cfg) + tu_le16toh(desc_cfg->wTotalLength);
-  uint8_t const* p_desc   = tu_desc_next(desc_cfg);
+void parse_config_descriptor(uint8_t dev_addr, tusb_desc_configuration_t const *desc_cfg) {
+  uint8_t const *desc_end = ((uint8_t const *) desc_cfg) + tu_le16toh(desc_cfg->wTotalLength);
+  uint8_t const *p_desc = tu_desc_next(desc_cfg);
 
   // parse each interfaces
-  while( p_desc < desc_end )
-  {
+  while (p_desc < desc_end) {
     uint8_t assoc_itf_count = 1;
 
     // Class will always starts with Interface Association (if any) and then Interface descriptor
-    if ( TUSB_DESC_INTERFACE_ASSOCIATION == tu_desc_type(p_desc) )
-    {
-      tusb_desc_interface_assoc_t const * desc_iad = (tusb_desc_interface_assoc_t const *) p_desc;
+    if (TUSB_DESC_INTERFACE_ASSOCIATION == tu_desc_type(p_desc)) {
+      tusb_desc_interface_assoc_t const *desc_iad = (tusb_desc_interface_assoc_t const *) p_desc;
       assoc_itf_count = desc_iad->bInterfaceCount;
 
-      p_desc = tu_desc_next(p_desc); // next to Interface
+      p_desc = tu_desc_next(p_desc);// next to Interface
     }
 
     // must be interface from now
-    if( TUSB_DESC_INTERFACE != tu_desc_type(p_desc) ) return;
-    tusb_desc_interface_t const* desc_itf = (tusb_desc_interface_t const*) p_desc;
+    if (TUSB_DESC_INTERFACE != tu_desc_type(p_desc)) { return; }
+    tusb_desc_interface_t const *desc_itf = (tusb_desc_interface_t const *) p_desc;
 
-    uint16_t const drv_len = count_interface_total_len(desc_itf, assoc_itf_count, (uint16_t) (desc_end-p_desc));
+    uint16_t const drv_len = count_interface_total_len(desc_itf, assoc_itf_count, (uint16_t) (desc_end - p_desc));
 
     // probably corrupted descriptor
-    if(drv_len < sizeof(tusb_desc_interface_t)) return;
+    if (drv_len < sizeof(tusb_desc_interface_t)) { return; }
 
     // only open and listen to HID endpoint IN
-    if (desc_itf->bInterfaceClass == TUSB_CLASS_HID)
-    {
+    if (desc_itf->bInterfaceClass == TUSB_CLASS_HID) {
       open_hid_interface(dev_addr, desc_itf, drv_len);
     }
 
@@ -210,25 +195,21 @@ void parse_config_descriptor(uint8_t dev_addr, tusb_desc_configuration_t const*
   }
 }
 
-uint16_t count_interface_total_len(tusb_desc_interface_t const* desc_itf, uint8_t itf_count, uint16_t max_len)
-{
-  uint8_t const* p_desc = (uint8_t const*) desc_itf;
+uint16_t count_interface_total_len(tusb_desc_interface_t const *desc_itf, uint8_t itf_count, uint16_t max_len) {
+  uint8_t const *p_desc = (uint8_t const *) desc_itf;
   uint16_t len = 0;
 
-  while (itf_count--)
-  {
+  while (itf_count--) {
     // Next on interface desc
     len += tu_desc_len(desc_itf);
     p_desc = tu_desc_next(p_desc);
 
-    while (len < max_len)
-    {
+    while (len < max_len) {
       // return on IAD regardless of itf count
-      if ( tu_desc_type(p_desc) == TUSB_DESC_INTERFACE_ASSOCIATION ) return len;
+      if (tu_desc_type(p_desc) == TUSB_DESC_INTERFACE_ASSOCIATION) { return len; }
 
-      if ( (tu_desc_type(p_desc) == TUSB_DESC_INTERFACE) &&
-           ((tusb_desc_interface_t const*) p_desc)->bAlternateSetting == 0 )
-      {
+      if ((tu_desc_type(p_desc) == TUSB_DESC_INTERFACE) &&
+          ((tusb_desc_interface_t const *) p_desc)->bAlternateSetting == 0) {
         break;
       }
 
@@ -246,46 +227,45 @@ uint16_t count_interface_total_len(tusb_desc_interface_t const* desc_itf, uint8_
 
 void hid_report_received(tuh_xfer_t* xfer);
 
-void open_hid_interface(uint8_t daddr, tusb_desc_interface_t const *desc_itf, uint16_t max_len)
-{
+void open_hid_interface(uint8_t daddr, tusb_desc_interface_t const *desc_itf, uint16_t max_len) {
   // len = interface + hid + n*endpoints
   uint16_t const drv_len = (uint16_t) (sizeof(tusb_desc_interface_t) + sizeof(tusb_hid_descriptor_hid_t) +
                                        desc_itf->bNumEndpoints * sizeof(tusb_desc_endpoint_t));
 
   // corrupted descriptor
-  if (max_len < drv_len) return;
+  if (max_len < drv_len) { return; }
 
   uint8_t const *p_desc = (uint8_t const *) desc_itf;
 
   // HID descriptor
   p_desc = tu_desc_next(p_desc);
   tusb_hid_descriptor_hid_t const *desc_hid = (tusb_hid_descriptor_hid_t const *) p_desc;
-  if(HID_DESC_TYPE_HID != desc_hid->bDescriptorType) return;
+  if (HID_DESC_TYPE_HID != desc_hid->bDescriptorType) { return; }
 
   // Endpoint descriptor
   p_desc = tu_desc_next(p_desc);
-  tusb_desc_endpoint_t const * desc_ep = (tusb_desc_endpoint_t const *) p_desc;
+  tusb_desc_endpoint_t const *desc_ep = (tusb_desc_endpoint_t const *) p_desc;
 
-  for(int i = 0; i < desc_itf->bNumEndpoints; i++)
-  {
-    if (TUSB_DESC_ENDPOINT != desc_ep->bDescriptorType) return;
+  for (int i = 0; i < desc_itf->bNumEndpoints; i++) {
+    if (TUSB_DESC_ENDPOINT != desc_ep->bDescriptorType) { return; }
 
-    if(tu_edpt_dir(desc_ep->bEndpointAddress) == TUSB_DIR_IN)
-    {
-      // skip if failed to open endpoint
-      if ( ! tuh_edpt_open(daddr, desc_ep) ) return;
+    if (tu_edpt_dir(desc_ep->bEndpointAddress) == TUSB_DIR_IN) {
+      if (!tuh_edpt_open(daddr, desc_ep)) {
+        return; // skip if failed to open endpoint
+      }
 
-      uint8_t* buf = get_hid_buf(daddr);
-      if (!buf) return; // out of memory
+      uint8_t *buf = get_hid_buf(daddr);
+      if (!buf) {
+        return;// out of memory
+      }
 
-      tuh_xfer_t xfer =
-      {
-        .daddr       = daddr,
-        .ep_addr     = desc_ep->bEndpointAddress,
-        .buflen      = 64,
-        .buffer      = buf,
-        .complete_cb = hid_report_received,
-        .user_data   = (uintptr_t) buf, // since buffer is not available in callback, use user data to store the buffer
+      tuh_xfer_t xfer = {
+          .daddr = daddr,
+          .ep_addr = desc_ep->bEndpointAddress,
+          .buflen = 64,
+          .buffer = buf,
+          .complete_cb = hid_report_received,
+          .user_data = (uintptr_t) buf,// since buffer is not available in callback, use user data to store the buffer
       };
 
       // submit transfer for this EP
@@ -299,18 +279,17 @@ void open_hid_interface(uint8_t daddr, tusb_desc_interface_t const *desc_itf, ui
   }
 }
 
-void hid_report_received(tuh_xfer_t* xfer)
-{
+void hid_report_received(tuh_xfer_t *xfer) {
   // Note: not all field in xfer is available for use (i.e filled by tinyusb stack) in callback to save sram
   // For instance, xfer->buffer is NULL. We have used user_data to store buffer when submitted callback
-  uint8_t* buf = (uint8_t*) xfer->user_data;
+  uint8_t *buf = (uint8_t *) xfer->user_data;
 
-  if (xfer->result == XFER_RESULT_SUCCESS)
-  {
+  if (xfer->result == XFER_RESULT_SUCCESS) {
     printf("[dev %u: ep %02x] HID Report:", xfer->daddr, xfer->ep_addr);
-    for(uint32_t i=0; i<xfer->actual_len; i++)
-    {
-      if (i%16 == 0) printf("\r\n  ");
+    for (uint32_t i = 0; i < xfer->actual_len; i++) {
+      if (i % 16 == 0) {
+        printf("\r\n  ");
+      }
       printf("%02X ", buf[i]);
     }
     printf("\r\n");
@@ -329,12 +308,9 @@ void hid_report_received(tuh_xfer_t* xfer)
 //--------------------------------------------------------------------+
 
 // get an buffer from pool
-uint8_t* get_hid_buf(uint8_t daddr)
-{
-  for(size_t i=0; i<BUF_COUNT; i++)
-  {
-    if (buf_owner[i] == 0)
-    {
+uint8_t *get_hid_buf(uint8_t daddr) {
+  for (size_t i = 0; i < BUF_COUNT; i++) {
+    if (buf_owner[i] == 0) {
       buf_owner[i] = daddr;
       return buf_pool[i];
     }
@@ -345,10 +321,8 @@ uint8_t* get_hid_buf(uint8_t daddr)
 }
 
 // free all buffer owned by device
-void free_hid_buf(uint8_t daddr)
-{
-  for(size_t i=0; i<BUF_COUNT; i++)
-  {
+void free_hid_buf(uint8_t daddr) {
+  for (size_t i = 0; i < BUF_COUNT; i++) {
     if (buf_owner[i] == daddr) buf_owner[i] = 0;
   }
 }
@@ -356,70 +330,70 @@ void free_hid_buf(uint8_t daddr)
 //--------------------------------------------------------------------+
 // Blinking Task
 //--------------------------------------------------------------------+
-void led_blinking_task(void)
-{
+void led_blinking_task(void) {
   const uint32_t interval_ms = 1000;
   static uint32_t start_ms = 0;
 
   static bool led_state = false;
 
   // Blink every interval ms
-  if ( board_millis() - start_ms < interval_ms) return; // not enough time
+  if (board_millis() - start_ms < interval_ms) {
+    return; // not enough time
+  }
   start_ms += interval_ms;
 
   board_led_write(led_state);
-  led_state = 1 - led_state; // toggle
+  led_state = 1 - led_state;// toggle
 }
 
 //--------------------------------------------------------------------+
 // String Descriptor Helper
 //--------------------------------------------------------------------+
-
 static void _convert_utf16le_to_utf8(const uint16_t *utf16, size_t utf16_len, uint8_t *utf8, size_t utf8_len) {
-    // TODO: Check for runover.
-    (void)utf8_len;
-    // Get the UTF-16 length out of the data itself.
+  // TODO: Check for runover.
+  (void) utf8_len;
+  // Get the UTF-16 length out of the data itself.
 
-    for (size_t i = 0; i < utf16_len; i++) {
-        uint16_t chr = utf16[i];
-        if (chr < 0x80) {
-            *utf8++ = chr & 0xffu;
-        } else if (chr < 0x800) {
-            *utf8++ = (uint8_t)(0xC0 | (chr >> 6 & 0x1F));
-            *utf8++ = (uint8_t)(0x80 | (chr >> 0 & 0x3F));
-        } else {
-            // TODO: Verify surrogate.
-            *utf8++ = (uint8_t)(0xE0 | (chr >> 12 & 0x0F));
-            *utf8++ = (uint8_t)(0x80 | (chr >> 6 & 0x3F));
-            *utf8++ = (uint8_t)(0x80 | (chr >> 0 & 0x3F));
-        }
-        // TODO: Handle UTF-16 code points that take two entries.
+  for (size_t i = 0; i < utf16_len; i++) {
+    uint16_t chr = utf16[i];
+    if (chr < 0x80) {
+      *utf8++ = chr & 0xffu;
+    } else if (chr < 0x800) {
+      *utf8++ = (uint8_t) (0xC0 | (chr >> 6 & 0x1F));
+      *utf8++ = (uint8_t) (0x80 | (chr >> 0 & 0x3F));
+    } else {
+      // TODO: Verify surrogate.
+      *utf8++ = (uint8_t) (0xE0 | (chr >> 12 & 0x0F));
+      *utf8++ = (uint8_t) (0x80 | (chr >> 6 & 0x3F));
+      *utf8++ = (uint8_t) (0x80 | (chr >> 0 & 0x3F));
     }
+    // TODO: Handle UTF-16 code points that take two entries.
+  }
 }
 
 // Count how many bytes a utf-16-le encoded string will take in utf-8.
 static int _count_utf8_bytes(const uint16_t *buf, size_t len) {
-    size_t total_bytes = 0;
-    for (size_t i = 0; i < len; i++) {
-        uint16_t chr = buf[i];
-        if (chr < 0x80) {
-            total_bytes += 1;
-        } else if (chr < 0x800) {
-            total_bytes += 2;
-        } else {
-            total_bytes += 3;
-        }
-        // TODO: Handle UTF-16 code points that take two entries.
+  size_t total_bytes = 0;
+  for (size_t i = 0; i < len; i++) {
+    uint16_t chr = buf[i];
+    if (chr < 0x80) {
+      total_bytes += 1;
+    } else if (chr < 0x800) {
+      total_bytes += 2;
+    } else {
+      total_bytes += 3;
     }
-    return (int) total_bytes;
+    // TODO: Handle UTF-16 code points that take two entries.
+  }
+  return (int) total_bytes;
 }
 
 static void print_utf16(uint16_t *temp_buf, size_t buf_len) {
-    if ((temp_buf[0] & 0xff) == 0) return;  // empty
-    size_t utf16_len = ((temp_buf[0] & 0xff) - 2) / sizeof(uint16_t);
-    size_t utf8_len = (size_t) _count_utf8_bytes(temp_buf + 1, utf16_len);
-    _convert_utf16le_to_utf8(temp_buf + 1, utf16_len, (uint8_t *) temp_buf, sizeof(uint16_t) * buf_len);
-    ((uint8_t*) temp_buf)[utf8_len] = '\0';
+  if ((temp_buf[0] & 0xff) == 0) return;// empty
+  size_t utf16_len = ((temp_buf[0] & 0xff) - 2) / sizeof(uint16_t);
+  size_t utf8_len = (size_t) _count_utf8_bytes(temp_buf + 1, utf16_len);
+  _convert_utf16le_to_utf8(temp_buf + 1, utf16_len, (uint8_t *) temp_buf, sizeof(uint16_t) * buf_len);
+  ((uint8_t *) temp_buf)[utf8_len] = '\0';
 
-    printf("%s", (char*)temp_buf);
+  printf("%s", (char *) temp_buf);
 }
diff --git a/examples/host/cdc_msc_hid/src/cdc_app.c b/examples/host/cdc_msc_hid/src/cdc_app.c
index 4a13f8b27..e68ec383b 100644
--- a/examples/host/cdc_msc_hid/src/cdc_app.c
+++ b/examples/host/cdc_msc_hid/src/cdc_app.c
@@ -27,7 +27,7 @@
 #include "tusb.h"
 #include "bsp/board_api.h"
 
-size_t get_console_inputs(uint8_t* buf, size_t bufsize) {
+static size_t get_console_inputs(uint8_t* buf, size_t bufsize) {
   size_t count = 0;
   while (count < bufsize) {
     int ch = board_getchar();
diff --git a/examples/host/cdc_msc_hid/src/hid_app.c b/examples/host/cdc_msc_hid/src/hid_app.c
index 5bae250cf..a751c9c80 100644
--- a/examples/host/cdc_msc_hid/src/hid_app.c
+++ b/examples/host/cdc_msc_hid/src/hid_app.c
@@ -165,8 +165,7 @@ static void process_kbd_report(hid_keyboard_report_t const *report)
 // Mouse
 //--------------------------------------------------------------------+
 
-void cursor_movement(int8_t x, int8_t y, int8_t wheel)
-{
+static void cursor_movement(int8_t x, int8_t y, int8_t wheel) {
 #if USE_ANSI_ESCAPE
   // Move X using ansi escape
   if ( x < 0)
diff --git a/examples/host/cdc_msc_hid/src/main.c b/examples/host/cdc_msc_hid/src/main.c
index 2d5df23f9..7b02e238e 100644
--- a/examples/host/cdc_msc_hid/src/main.c
+++ b/examples/host/cdc_msc_hid/src/main.c
@@ -31,18 +31,12 @@
 #include "tusb.h"
 
 //--------------------------------------------------------------------+
-// MACRO CONSTANT TYPEDEF PROTYPES
+// MACRO CONSTANT TYPEDEF PROTOTYPES
 //--------------------------------------------------------------------+
 void led_blinking_task(void);
 extern void cdc_app_task(void);
 extern void hid_app_task(void);
 
-#if CFG_TUH_ENABLED && CFG_TUH_MAX3421
-// API to read/rite MAX3421's register. Implemented by TinyUSB
-extern uint8_t tuh_max3421_reg_read(uint8_t rhport, uint8_t reg, bool in_isr);
-extern bool tuh_max3421_reg_write(uint8_t rhport, uint8_t reg, uint8_t data, bool in_isr);
-#endif
-
 /*------------- MAIN -------------*/
 int main(void) {
   board_init();
@@ -101,7 +95,9 @@ void led_blinking_task(void) {
   static bool led_state = false;
 
   // Blink every interval ms
-  if (board_millis() - start_ms < interval_ms) return; // not enough time
+  if (board_millis() - start_ms < interval_ms) {
+    return;// not enough time
+  }
   start_ms += interval_ms;
 
   board_led_write(led_state);
diff --git a/examples/host/cdc_msc_hid/src/msc_app.c b/examples/host/cdc_msc_hid/src/msc_app.c
index 1d7e18e6e..0e9c99766 100644
--- a/examples/host/cdc_msc_hid/src/msc_app.c
+++ b/examples/host/cdc_msc_hid/src/msc_app.c
@@ -30,13 +30,11 @@
 //--------------------------------------------------------------------+
 static scsi_inquiry_resp_t inquiry_resp;
 
-bool inquiry_complete_cb(uint8_t dev_addr, tuh_msc_complete_data_t const * cb_data)
-{
+static bool inquiry_complete_cb(uint8_t dev_addr, tuh_msc_complete_data_t const * cb_data) {
   msc_cbw_t const* cbw = cb_data->cbw;
   msc_csw_t const* csw = cb_data->csw;
 
-  if (csw->status != 0)
-  {
+  if (csw->status != 0) {
     printf("Inquiry failed\r\n");
     return false;
   }
@@ -55,16 +53,14 @@ bool inquiry_complete_cb(uint8_t dev_addr, tuh_msc_complete_data_t const * cb_da
 }
 
 //------------- IMPLEMENTATION -------------//
-void tuh_msc_mount_cb(uint8_t dev_addr)
-{
+void tuh_msc_mount_cb(uint8_t dev_addr) {
   printf("A MassStorage device is mounted\r\n");
 
   uint8_t const lun = 0;
   tuh_msc_inquiry(dev_addr, lun, &inquiry_resp, inquiry_complete_cb, 0);
 }
 
-void tuh_msc_umount_cb(uint8_t dev_addr)
-{
+void tuh_msc_umount_cb(uint8_t dev_addr) {
   (void) dev_addr;
   printf("A MassStorage device is unmounted\r\n");
 }
diff --git a/examples/host/cdc_msc_hid_freertos/src/cdc_app.c b/examples/host/cdc_msc_hid_freertos/src/cdc_app.c
index 7cbe1e03a..e279ad509 100644
--- a/examples/host/cdc_msc_hid_freertos/src/cdc_app.c
+++ b/examples/host/cdc_msc_hid_freertos/src/cdc_app.c
@@ -52,7 +52,7 @@ void cdc_app_init(void) {
 }
 
 // helper
-size_t get_console_inputs(uint8_t *buf, size_t bufsize) {
+static size_t get_console_inputs(uint8_t *buf, size_t bufsize) {
   size_t count = 0;
   while (count < bufsize) {
     int ch = board_getchar();
diff --git a/examples/host/cdc_msc_hid_freertos/src/main.c b/examples/host/cdc_msc_hid_freertos/src/main.c
index 10d1b120b..64a108254 100644
--- a/examples/host/cdc_msc_hid_freertos/src/main.c
+++ b/examples/host/cdc_msc_hid_freertos/src/main.c
@@ -69,12 +69,6 @@ extern void cdc_app_init(void);
 extern void hid_app_init(void);
 extern void msc_app_init(void);
 
-#if CFG_TUH_ENABLED && CFG_TUH_MAX3421
-// API to read/rite MAX3421's register. Implemented by TinyUSB
-extern uint8_t tuh_max3421_reg_read(uint8_t rhport, uint8_t reg, bool in_isr);
-extern bool tuh_max3421_reg_write(uint8_t rhport, uint8_t reg, uint8_t data, bool in_isr);
-#endif
-
 /*------------- MAIN -------------*/
 int main(void) {
   board_init();
diff --git a/examples/host/cdc_msc_hid_freertos/src/msc_app.c b/examples/host/cdc_msc_hid_freertos/src/msc_app.c
index 6b9cdab85..6439495a8 100644
--- a/examples/host/cdc_msc_hid_freertos/src/msc_app.c
+++ b/examples/host/cdc_msc_hid_freertos/src/msc_app.c
@@ -34,7 +34,7 @@ void msc_app_init(void) {
   // nothing to do
 }
 
-bool inquiry_complete_cb(uint8_t dev_addr, tuh_msc_complete_data_t const *cb_data) {
+static bool inquiry_complete_cb(uint8_t dev_addr, tuh_msc_complete_data_t const *cb_data) {
   msc_cbw_t const *cbw = cb_data->cbw;
   msc_csw_t const *csw = cb_data->csw;
 
diff --git a/examples/host/device_info/src/main.c b/examples/host/device_info/src/main.c
index 775968c16..e924a137b 100644
--- a/examples/host/device_info/src/main.c
+++ b/examples/host/device_info/src/main.c
@@ -81,7 +81,7 @@ void init_freertos_task(void);
 //--------------------------------------------------------------------
 // Main
 //--------------------------------------------------------------------
-void init_tinyusb(void) {
+static void init_tinyusb(void) {
   // init host stack on configured roothub port
   tusb_rhport_init_t host_init = {
     .role = TUSB_ROLE_HOST,
@@ -124,13 +124,18 @@ void tuh_mount_cb(uint8_t daddr) {
   }
 
   printf("Device %u: ID %04x:%04x SN ", daddr, desc.device.idVendor, desc.device.idProduct);
-  xfer_result = tuh_descriptor_get_serial_string_sync(daddr, LANGUAGE_ID, desc.serial, sizeof(desc.serial));
+
+  xfer_result = XFER_RESULT_FAILED;
+  if (desc.device.iSerialNumber != 0) {
+    xfer_result = tuh_descriptor_get_serial_string_sync(daddr, LANGUAGE_ID, desc.serial, sizeof(desc.serial));
+  }
   if (XFER_RESULT_SUCCESS != xfer_result) {
     uint16_t* serial = (uint16_t*)(uintptr_t) desc.serial;
-    serial[0] = 'n';
-    serial[1] = '/';
-    serial[2] = 'a';
-    serial[3] = 0;
+    serial[0] = (uint16_t) ((TUSB_DESC_STRING << 8) | (2 * 3 + 2));
+    serial[1] = 'n';
+    serial[2] = '/';
+    serial[3] = 'a';
+    serial[4] = 0;
   }
   print_utf16((uint16_t*)(uintptr_t) desc.serial, sizeof(desc.serial)/2);
   printf("\r\n");
@@ -150,16 +155,20 @@ void tuh_mount_cb(uint8_t daddr) {
   // Get String descriptor using Sync API
 
   printf("  iManufacturer       %u     ", desc.device.iManufacturer);
-  xfer_result = tuh_descriptor_get_manufacturer_string_sync(daddr, LANGUAGE_ID, desc.buf, sizeof(desc.buf));
-  if (XFER_RESULT_SUCCESS == xfer_result) {
-    print_utf16((uint16_t*)(uintptr_t) desc.buf, sizeof(desc.buf)/2);
+  if (desc.device.iManufacturer != 0) {
+    xfer_result = tuh_descriptor_get_manufacturer_string_sync(daddr, LANGUAGE_ID, desc.buf, sizeof(desc.buf));
+    if (XFER_RESULT_SUCCESS == xfer_result) {
+      print_utf16((uint16_t*)(uintptr_t) desc.buf, sizeof(desc.buf)/2);
+    }
   }
   printf("\r\n");
 
   printf("  iProduct            %u     ", desc.device.iProduct);
-  xfer_result = tuh_descriptor_get_product_string_sync(daddr, LANGUAGE_ID, desc.buf, sizeof(desc.buf));
-  if (XFER_RESULT_SUCCESS == xfer_result) {
-    print_utf16((uint16_t*)(uintptr_t) desc.buf, sizeof(desc.buf)/2);
+  if (desc.device.iProduct != 0) {
+    xfer_result = tuh_descriptor_get_product_string_sync(daddr, LANGUAGE_ID, desc.buf, sizeof(desc.buf));
+    if (XFER_RESULT_SUCCESS == xfer_result) {
+      print_utf16((uint16_t*)(uintptr_t) desc.buf, sizeof(desc.buf)/2);
+    }
   }
   printf("\r\n");
 
diff --git a/examples/host/hid_controller/src/hid_app.c b/examples/host/hid_controller/src/hid_app.c
index 6ffe0b6d4..1d6ca8b07 100644
--- a/examples/host/hid_controller/src/hid_app.c
+++ b/examples/host/hid_controller/src/hid_app.c
@@ -231,14 +231,12 @@ void tuh_hid_umount_cb(uint8_t dev_addr, uint8_t instance)
 }
 
 // check if different than 2
-bool diff_than_2(uint8_t x, uint8_t y)
-{
+static inline bool diff_than_2(uint8_t x, uint8_t y) {
   return (x - y > 2) || (y - x > 2);
 }
 
 // check if 2 reports are different enough
-bool diff_report(sony_ds4_report_t const* rpt1, sony_ds4_report_t const* rpt2)
-{
+static bool diff_report(sony_ds4_report_t const* rpt1, sony_ds4_report_t const* rpt2) {
   bool result;
 
   // x, y, z, rz must different than 2 to be counted
@@ -251,7 +249,7 @@ bool diff_report(sony_ds4_report_t const* rpt1, sony_ds4_report_t const* rpt2)
   return result;
 }
 
-void process_sony_ds4(uint8_t const* report, uint16_t len)
+static void process_sony_ds4(uint8_t const* report, uint16_t len)
 {
   (void)len;
   const char* dpad_str[] = { "N", "NE", "E", "SE", "S", "SW", "W", "NW", "none" };
@@ -310,16 +308,13 @@ void process_sony_ds4(uint8_t const* report, uint16_t len)
 }
 
 // Invoked when received report from device via interrupt endpoint
-void tuh_hid_report_received_cb(uint8_t dev_addr, uint8_t instance, uint8_t const* report, uint16_t len)
-{
-  if ( is_sony_ds4(dev_addr) )
-  {
+void tuh_hid_report_received_cb(uint8_t dev_addr, uint8_t instance, uint8_t const *report, uint16_t len) {
+  if (is_sony_ds4(dev_addr)) {
     process_sony_ds4(report, len);
   }
 
   // continue to request to receive report
-  if ( !tuh_hid_receive_report(dev_addr, instance) )
-  {
+  if (!tuh_hid_receive_report(dev_addr, instance)) {
     printf("Error: cannot request to receive report\r\n");
   }
 }
diff --git a/examples/host/msc_file_explorer/Makefile b/examples/host/msc_file_explorer/Makefile
index c7d6a7cae..f0872376f 100644
--- a/examples/host/msc_file_explorer/Makefile
+++ b/examples/host/msc_file_explorer/Makefile
@@ -22,6 +22,6 @@ SRC_C += \
   $(FATFS_PATH)/ffunicode.c \
 
 # suppress warning caused by fatfs
-CFLAGS += -Wno-error=cast-qual
+CFLAGS_GCC += -Wno-error=cast-qual
 
 include ../../build_system/make/rules.mk
diff --git a/examples/host/msc_file_explorer/src/msc_app.c b/examples/host/msc_file_explorer/src/msc_app.c
index 226c870ea..40a9ef57e 100644
--- a/examples/host/msc_file_explorer/src/msc_app.c
+++ b/examples/host/msc_file_explorer/src/msc_app.c
@@ -34,6 +34,8 @@
 #define EMBEDDED_CLI_IMPL
 #include "embedded_cli.h"
 
+#include "msc_app.h"
+
 
 //--------------------------------------------------------------------+
 // MACRO TYPEDEF CONSTANT ENUM DECLARATION