diff --git a/examples/device/audio_4_channel_mic/src/usb_descriptors.c b/examples/device/audio_4_channel_mic/src/usb_descriptors.c
index 728a5f9ce..c8abf491d 100644
--- a/examples/device/audio_4_channel_mic/src/usb_descriptors.c
+++ b/examples/device/audio_4_channel_mic/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
diff --git a/examples/device/audio_4_channel_mic_freertos/src/usb_descriptors.c b/examples/device/audio_4_channel_mic_freertos/src/usb_descriptors.c
index 728a5f9ce..c8abf491d 100644
--- a/examples/device/audio_4_channel_mic_freertos/src/usb_descriptors.c
+++ b/examples/device/audio_4_channel_mic_freertos/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
diff --git a/examples/device/audio_test/src/usb_descriptors.c b/examples/device/audio_test/src/usb_descriptors.c
index 9864377f6..5e448002d 100644
--- a/examples/device/audio_test/src/usb_descriptors.c
+++ b/examples/device/audio_test/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
diff --git a/examples/device/audio_test_freertos/src/usb_descriptors.c b/examples/device/audio_test_freertos/src/usb_descriptors.c
index 9864377f6..5e448002d 100644
--- a/examples/device/audio_test_freertos/src/usb_descriptors.c
+++ b/examples/device/audio_test_freertos/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
diff --git a/examples/device/audio_test_multi_rate/src/usb_descriptors.c b/examples/device/audio_test_multi_rate/src/usb_descriptors.c
index f50e70a25..e54af14fb 100644
--- a/examples/device/audio_test_multi_rate/src/usb_descriptors.c
+++ b/examples/device/audio_test_multi_rate/src/usb_descriptors.c
@@ -41,7 +41,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
diff --git a/examples/device/cdc_dual_ports/src/usb_descriptors.c b/examples/device/cdc_dual_ports/src/usb_descriptors.c
index bbcb479f5..6b3963814 100644
--- a/examples/device/cdc_dual_ports/src/usb_descriptors.c
+++ b/examples/device/cdc_dual_ports/src/usb_descriptors.c
@@ -42,7 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -127,7 +127,7 @@ enum {
   #define EPNUM_CDC_1_IN      0x84
 #endif
 
-uint8_t const desc_fs_configuration[] = {
+static uint8_t const desc_fs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -140,7 +140,7 @@ uint8_t const desc_fs_configuration[] = {
 
 #if TUD_OPT_HIGH_SPEED
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -152,7 +152,7 @@ uint8_t const desc_hs_configuration[] = {
 };
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
   .bLength            = sizeof(tusb_desc_device_t),
   .bDescriptorType    = TUSB_DESC_DEVICE,
   .bcdUSB             = USB_BCD,
@@ -213,7 +213,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] = {
+static char const *string_desc_arr[] = {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
   "TinyUSB Device",              // 2: Product
diff --git a/examples/device/cdc_msc/src/main.c b/examples/device/cdc_msc/src/main.c
index 4e7aa989e..c4606528a 100644
--- a/examples/device/cdc_msc/src/main.c
+++ b/examples/device/cdc_msc/src/main.c
@@ -42,6 +42,7 @@ enum {
 };
 
 static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
+static bool blink_enable = true;
 
 void led_blinking_task(void);
 void cdc_task(void);
@@ -135,11 +136,13 @@ void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts) {
   (void) itf;
   (void) rts;
 
-  // TODO set some indicator
   if (dtr) {
     // Terminal connected
+    blink_enable = false;
+    board_led_write(true);
   } else {
     // Terminal disconnected
+    blink_enable = true;
   }
 }
 
@@ -155,10 +158,14 @@ void led_blinking_task(void) {
   static uint32_t start_ms = 0;
   static bool led_state = false;
 
-  // Blink every interval ms
-  if (board_millis() - start_ms < blink_interval_ms) return; // not enough time
-  start_ms += blink_interval_ms;
+  if (blink_enable) {
+    // Blink every interval ms
+    if (board_millis() - start_ms < blink_interval_ms) {
+      return; // not enough time
+    }
+    start_ms += blink_interval_ms;
 
-  board_led_write(led_state);
-  led_state = 1 - led_state; // toggle
+    board_led_write(led_state);
+    led_state = !led_state;
+  }
 }
diff --git a/examples/device/cdc_msc/src/msc_disk.c b/examples/device/cdc_msc/src/msc_disk.c
index 6c112aa8b..9a43d321e 100644
--- a/examples/device/cdc_msc/src/msc_disk.c
+++ b/examples/device/cdc_msc/src/msc_disk.c
@@ -48,7 +48,7 @@ enum {
 #ifdef CFG_EXAMPLE_MSC_READONLY
 const
 #endif
-uint8_t msc_disk[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] = {
+static 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;
@@ -213,7 +213,9 @@ int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t *
   (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;
diff --git a/examples/device/cdc_msc/src/usb_descriptors.c b/examples/device/cdc_msc/src/usb_descriptors.c
index 597a6b1e6..4fe03f90e 100644
--- a/examples/device/cdc_msc/src/usb_descriptors.c
+++ b/examples/device/cdc_msc/src/usb_descriptors.c
@@ -42,7 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -125,7 +125,7 @@ enum {
 #define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN + TUD_MSC_DESC_LEN)
 
 // full speed configuration
-uint8_t const desc_fs_configuration[] = {
+static uint8_t const desc_fs_configuration[] = {
     // Config number, interface count, string index, total length, attribute, power in mA
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -140,7 +140,7 @@ uint8_t const desc_fs_configuration[] = {
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // high speed configuration
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
     // Config number, interface count, string index, total length, attribute, power in mA
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -152,10 +152,10 @@ uint8_t const desc_hs_configuration[] = {
 };
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
     .bLength            = sizeof(tusb_desc_device_qualifier_t),
     .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
     .bcdUSB             = USB_BCD,
@@ -223,7 +223,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] = {
+static char const *string_desc_arr[] = {
     (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
     "TinyUSB",                     // 1: Manufacturer
     "TinyUSB Device",              // 2: Product
diff --git a/examples/device/cdc_msc_freertos/src/msc_disk.c b/examples/device/cdc_msc_freertos/src/msc_disk.c
index 38345ca4d..996be738d 100644
--- a/examples/device/cdc_msc_freertos/src/msc_disk.c
+++ b/examples/device/cdc_msc_freertos/src/msc_disk.c
@@ -79,7 +79,7 @@ enum {
 #ifdef CFG_EXAMPLE_MSC_READONLY
 const
 #endif
-uint8_t msc_disk[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
+static 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;
diff --git a/examples/device/cdc_msc_freertos/src/usb_descriptors.c b/examples/device/cdc_msc_freertos/src/usb_descriptors.c
index cb440c209..bcfef48a7 100644
--- a/examples/device/cdc_msc_freertos/src/usb_descriptors.c
+++ b/examples/device/cdc_msc_freertos/src/usb_descriptors.c
@@ -42,7 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -124,7 +124,7 @@ enum {
 
 #define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN + TUD_MSC_DESC_LEN)
 
-uint8_t const desc_fs_configuration[] =
+static uint8_t const desc_fs_configuration[] =
 {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
@@ -140,7 +140,7 @@ uint8_t const desc_fs_configuration[] =
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // high speed configuration
-uint8_t const desc_hs_configuration[] =
+static uint8_t const desc_hs_configuration[] =
 {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
@@ -153,10 +153,10 @@ uint8_t const desc_hs_configuration[] =
 };
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier =
+static tusb_desc_device_qualifier_t const desc_device_qualifier =
 {
   .bLength            = sizeof(tusb_desc_device_qualifier_t),
   .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
@@ -225,7 +225,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] = {
+static char const *string_desc_arr[] = {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
   "TinyUSB Device",              // 2: Product
diff --git a/examples/device/cdc_uac2/src/usb_descriptors.c b/examples/device/cdc_uac2/src/usb_descriptors.c
index da55bdb5a..748c36b7b 100644
--- a/examples/device/cdc_uac2/src/usb_descriptors.c
+++ b/examples/device/cdc_uac2/src/usb_descriptors.c
@@ -42,7 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -116,7 +116,7 @@ uint8_t const * tud_descriptor_device_cb(void)
   #define EPNUM_CDC_IN      0x84
 #endif
 
-uint8_t const desc_fs_configuration[] =
+static uint8_t const desc_fs_configuration[] =
 {
     // Config number, interface count, string index, total length, attribute, power in mA
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
@@ -132,7 +132,7 @@ uint8_t const desc_fs_configuration[] =
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // high speed configuration
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
     // Config number, interface count, string index, total length, attribute, power in mA
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -144,10 +144,10 @@ uint8_t const desc_hs_configuration[] = {
 };
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
     .bLength            = sizeof(tusb_desc_device_qualifier_t),
     .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
     .bcdUSB             = 0x0100,
@@ -215,7 +215,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 },  // 0: is supported language is English (0x0409)
   "TinyUSB",                      // 1: Manufacturer
diff --git a/examples/device/dfu/src/usb_descriptors.c b/examples/device/dfu/src/usb_descriptors.c
index fd469aaf2..1550b70b8 100644
--- a/examples/device/dfu/src/usb_descriptors.c
+++ b/examples/device/dfu/src/usb_descriptors.c
@@ -40,7 +40,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -126,7 +126,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/dfu_runtime/src/usb_descriptors.c b/examples/device/dfu_runtime/src/usb_descriptors.c
index 7ac53d255..c5cc9f92f 100644
--- a/examples/device/dfu_runtime/src/usb_descriptors.c
+++ b/examples/device/dfu_runtime/src/usb_descriptors.c
@@ -40,7 +40,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -122,7 +122,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/dynamic_configuration/src/msc_disk.c b/examples/device/dynamic_configuration/src/msc_disk.c
index e57f9e3f3..95bf8e45f 100644
--- a/examples/device/dynamic_configuration/src/msc_disk.c
+++ b/examples/device/dynamic_configuration/src/msc_disk.c
@@ -46,7 +46,7 @@ enum
 #ifdef CFG_EXAMPLE_MSC_READONLY
 const
 #endif
-uint8_t msc_disk[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
+static 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;
diff --git a/examples/device/dynamic_configuration/src/usb_descriptors.c b/examples/device/dynamic_configuration/src/usb_descriptors.c
index 0a2049288..7660e59dd 100644
--- a/examples/device/dynamic_configuration/src/usb_descriptors.c
+++ b/examples/device/dynamic_configuration/src/usb_descriptors.c
@@ -202,7 +202,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/hid_boot_interface/src/usb_descriptors.c b/examples/device/hid_boot_interface/src/usb_descriptors.c
index d68ef16d9..d9ce4ef09 100644
--- a/examples/device/hid_boot_interface/src/usb_descriptors.c
+++ b/examples/device/hid_boot_interface/src/usb_descriptors.c
@@ -40,7 +40,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -140,7 +140,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/hid_composite/src/usb_descriptors.c b/examples/device/hid_composite/src/usb_descriptors.c
index ce7fbd13f..7b1f4f8d8 100644
--- a/examples/device/hid_composite/src/usb_descriptors.c
+++ b/examples/device/hid_composite/src/usb_descriptors.c
@@ -43,7 +43,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -120,10 +120,10 @@ uint8_t const desc_configuration[] =
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier =
+static tusb_desc_device_qualifier_t const desc_device_qualifier =
 {
   .bLength            = sizeof(tusb_desc_device_qualifier_t),
   .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
@@ -188,7 +188,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/hid_composite_freertos/src/usb_descriptors.c b/examples/device/hid_composite_freertos/src/usb_descriptors.c
index 3f231fecc..1d703beff 100644
--- a/examples/device/hid_composite_freertos/src/usb_descriptors.c
+++ b/examples/device/hid_composite_freertos/src/usb_descriptors.c
@@ -43,7 +43,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -119,10 +119,10 @@ uint8_t const desc_configuration[] =
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier =
+static tusb_desc_device_qualifier_t const desc_device_qualifier =
 {
   .bLength            = sizeof(tusb_desc_device_qualifier_t),
   .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
@@ -185,7 +185,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/hid_generic_inout/src/usb_descriptors.c b/examples/device/hid_generic_inout/src/usb_descriptors.c
index 64f6d17ae..1b5c055e6 100644
--- a/examples/device/hid_generic_inout/src/usb_descriptors.c
+++ b/examples/device/hid_generic_inout/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -130,7 +130,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/hid_multiple_interface/src/usb_descriptors.c b/examples/device/hid_multiple_interface/src/usb_descriptors.c
index 86f567e8e..145836300 100644
--- a/examples/device/hid_multiple_interface/src/usb_descriptors.c
+++ b/examples/device/hid_multiple_interface/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -146,7 +146,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 },  // 0: is supported language is English (0x0409)
   "TinyUSB",                      // 1: Manufacturer
diff --git a/examples/device/midi_test/src/usb_descriptors.c b/examples/device/midi_test/src/usb_descriptors.c
index 384742ae8..8cb235d30 100644
--- a/examples/device/midi_test/src/usb_descriptors.c
+++ b/examples/device/midi_test/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = 0x0200,
@@ -98,7 +98,7 @@ enum {
   #define EPNUM_MIDI_IN   0x81
 #endif
 
-uint8_t const desc_fs_configuration[] = {
+static uint8_t const desc_fs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -107,7 +107,7 @@ uint8_t const desc_fs_configuration[] = {
 };
 
 #if TUD_OPT_HIGH_SPEED
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -143,7 +143,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] = {
+static char const *string_desc_arr[] = {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
   "TinyUSB Device",              // 2: Product
diff --git a/examples/device/midi_test_freertos/src/usb_descriptors.c b/examples/device/midi_test_freertos/src/usb_descriptors.c
index 384742ae8..8cb235d30 100644
--- a/examples/device/midi_test_freertos/src/usb_descriptors.c
+++ b/examples/device/midi_test_freertos/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = 0x0200,
@@ -98,7 +98,7 @@ enum {
   #define EPNUM_MIDI_IN   0x81
 #endif
 
-uint8_t const desc_fs_configuration[] = {
+static uint8_t const desc_fs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -107,7 +107,7 @@ uint8_t const desc_fs_configuration[] = {
 };
 
 #if TUD_OPT_HIGH_SPEED
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -143,7 +143,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] = {
+static char const *string_desc_arr[] = {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
   "TinyUSB Device",              // 2: Product
diff --git a/examples/device/msc_dual_lun/src/usb_descriptors.c b/examples/device/msc_dual_lun/src/usb_descriptors.c
index efb9a966d..e3a0753b5 100644
--- a/examples/device/msc_dual_lun/src/usb_descriptors.c
+++ b/examples/device/msc_dual_lun/src/usb_descriptors.c
@@ -39,7 +39,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -103,7 +103,7 @@ enum
 
 #endif
 
-uint8_t const desc_fs_configuration[] =
+static uint8_t const desc_fs_configuration[] =
 {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
@@ -113,7 +113,7 @@ uint8_t const desc_fs_configuration[] =
 };
 
 #if TUD_OPT_HIGH_SPEED
-uint8_t const desc_hs_configuration[] =
+static uint8_t const desc_hs_configuration[] =
 {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
@@ -151,7 +151,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/mtp/src/usb_descriptors.c b/examples/device/mtp/src/usb_descriptors.c
index 80345d8f8..ff35e0df3 100644
--- a/examples/device/mtp/src/usb_descriptors.c
+++ b/examples/device/mtp/src/usb_descriptors.c
@@ -42,7 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -121,7 +121,7 @@ const uint8_t desc_fs_configuration[] = {
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // high speed configuration
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
   // Interface number, string index, EP event, EP event size, EP event polling, EP Out & EP In address, EP size
@@ -129,10 +129,10 @@ uint8_t const desc_hs_configuration[] = {
 };
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
     .bLength            = sizeof(tusb_desc_device_qualifier_t),
     .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
     .bcdUSB             = USB_BCD,
@@ -198,7 +198,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUsb",                     // 1: Manufacturer
diff --git a/examples/device/net_lwip_webserver/src/usb_descriptors.c b/examples/device/net_lwip_webserver/src/usb_descriptors.c
index cd800f521..57ee3a218 100644
--- a/examples/device/net_lwip_webserver/src/usb_descriptors.c
+++ b/examples/device/net_lwip_webserver/src/usb_descriptors.c
@@ -68,7 +68,7 @@ enum
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
diff --git a/examples/device/uac2_headset/src/usb_descriptors.c b/examples/device/uac2_headset/src/usb_descriptors.c
index fc12c122e..d2f4f45b3 100644
--- a/examples/device/uac2_headset/src/usb_descriptors.c
+++ b/examples/device/uac2_headset/src/usb_descriptors.c
@@ -41,7 +41,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -141,7 +141,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 },  // 0: is supported language is English (0x0409)
   "TinyUSB",                      // 1: Manufacturer
diff --git a/examples/device/uac2_speaker_fb/src/usb_descriptors.c b/examples/device/uac2_speaker_fb/src/usb_descriptors.c
index ee1b92225..cc904031b 100644
--- a/examples/device/uac2_speaker_fb/src/usb_descriptors.c
+++ b/examples/device/uac2_speaker_fb/src/usb_descriptors.c
@@ -45,7 +45,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -230,7 +230,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 },  // 0: is supported language is English (0x0409)
   "TinyUSB",                      // 1: Manufacturer
diff --git a/examples/device/usbtmc/src/usb_descriptors.c b/examples/device/usbtmc/src/usb_descriptors.c
index 85acd990a..d03c64102 100644
--- a/examples/device/usbtmc/src/usb_descriptors.c
+++ b/examples/device/usbtmc/src/usb_descriptors.c
@@ -44,7 +44,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -112,7 +112,7 @@ enum
 
 #define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_USBTMC_DESC_LEN)
 
-uint8_t const desc_fs_configuration[] =
+static uint8_t const desc_fs_configuration[] =
 {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
@@ -122,7 +122,7 @@ uint8_t const desc_fs_configuration[] =
 
 #if TUD_OPT_HIGH_SPEED
 
-uint8_t const desc_hs_configuration[] =
+static uint8_t const desc_hs_configuration[] =
 {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
@@ -131,10 +131,10 @@ uint8_t const desc_hs_configuration[] =
 };
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier =
+static tusb_desc_device_qualifier_t const desc_device_qualifier =
 {
   .bLength            = sizeof(tusb_desc_device_qualifier_t),
   .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
@@ -158,6 +158,23 @@ uint8_t const* tud_descriptor_device_qualifier_cb(void)
   return (uint8_t const*) &desc_device_qualifier;
 }
 
+// Invoked when received GET OTHER SEED CONFIGURATION DESCRIPTOR request
+// Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
+// Configuration descriptor in the other speed e.g if high speed then this is for full speed and vice versa
+uint8_t const *tud_descriptor_other_speed_configuration_cb(uint8_t index) {
+  (void) index; // for multiple configurations
+
+  // if link speed is high return fullspeed config, and vice versa
+  // Note: the descriptor type is OTHER_SPEED_CONFIG instead of CONFIG
+  memcpy(desc_other_speed_config,
+         (tud_speed_get() == TUSB_SPEED_HIGH) ? desc_fs_configuration : desc_hs_configuration,
+         CONFIG_TOTAL_LEN);
+
+  desc_other_speed_config[1] = TUSB_DESC_OTHER_SPEED_CONFIG;
+
+  return desc_other_speed_config;
+}
+
 #endif
 
 // Invoked when received GET CONFIGURATION DESCRIPTOR
@@ -187,7 +204,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/device/video_capture/src/usb_descriptors.c b/examples/device/video_capture/src/usb_descriptors.c
index b3e19b0f0..775386c65 100644
--- a/examples/device/video_capture/src/usb_descriptors.c
+++ b/examples/device/video_capture/src/usb_descriptors.c
@@ -63,7 +63,7 @@ char const* string_desc_arr[] = {
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -384,7 +384,7 @@ static uint8_t * get_hs_configuration_desc(void) {
 }
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
diff --git a/examples/device/video_capture_2ch/src/usb_descriptors.c b/examples/device/video_capture_2ch/src/usb_descriptors.c
index e78e452fc..03fac2d5c 100644
--- a/examples/device/video_capture_2ch/src/usb_descriptors.c
+++ b/examples/device/video_capture_2ch/src/usb_descriptors.c
@@ -68,7 +68,7 @@ char const* string_desc_arr[] = {
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -551,7 +551,7 @@ static uint8_t * get_hs_configuration_desc(void) {
 }
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
diff --git a/examples/device/webusb_serial/src/usb_descriptors.c b/examples/device/webusb_serial/src/usb_descriptors.c
index 2b69a5b56..044a6b294 100644
--- a/examples/device/webusb_serial/src/usb_descriptors.c
+++ b/examples/device/webusb_serial/src/usb_descriptors.c
@@ -40,7 +40,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
+static tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
@@ -228,7 +228,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
+static char const *string_desc_arr[] =
 {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
diff --git a/examples/dual/host_hid_to_device_cdc/src/usb_descriptors.c b/examples/dual/host_hid_to_device_cdc/src/usb_descriptors.c
index b7cffe23d..c2377cb00 100644
--- a/examples/dual/host_hid_to_device_cdc/src/usb_descriptors.c
+++ b/examples/dual/host_hid_to_device_cdc/src/usb_descriptors.c
@@ -42,7 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -122,7 +122,7 @@ enum {
 #define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN)
 
 // full speed configuration
-uint8_t const desc_fs_configuration[] = {
+static uint8_t const desc_fs_configuration[] = {
     // Config number, interface count, string index, total length, attribute, power in mA
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -134,7 +134,7 @@ uint8_t const desc_fs_configuration[] = {
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // high speed configuration
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -143,10 +143,10 @@ uint8_t const desc_hs_configuration[] = {
 };
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
   .bLength            = sizeof(tusb_desc_device_qualifier_t),
   .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
   .bcdUSB             = USB_BCD,
diff --git a/examples/dual/host_info_to_device_cdc/src/usb_descriptors.c b/examples/dual/host_info_to_device_cdc/src/usb_descriptors.c
index b7cffe23d..c2377cb00 100644
--- a/examples/dual/host_info_to_device_cdc/src/usb_descriptors.c
+++ b/examples/dual/host_info_to_device_cdc/src/usb_descriptors.c
@@ -42,7 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device = {
+static tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -122,7 +122,7 @@ enum {
 #define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN)
 
 // full speed configuration
-uint8_t const desc_fs_configuration[] = {
+static uint8_t const desc_fs_configuration[] = {
     // Config number, interface count, string index, total length, attribute, power in mA
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -134,7 +134,7 @@ uint8_t const desc_fs_configuration[] = {
 // Per USB specs: high speed capable device must report device_qualifier and other_speed_configuration
 
 // high speed configuration
-uint8_t const desc_hs_configuration[] = {
+static uint8_t const desc_hs_configuration[] = {
   // Config number, interface count, string index, total length, attribute, power in mA
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
@@ -143,10 +143,10 @@ uint8_t const desc_hs_configuration[] = {
 };
 
 // other speed configuration
-uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
+static uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN];
 
 // device qualifier is mostly similar to device descriptor since we don't change configuration based on speed
-tusb_desc_device_qualifier_t const desc_device_qualifier = {
+static tusb_desc_device_qualifier_t const desc_device_qualifier = {
   .bLength            = sizeof(tusb_desc_device_qualifier_t),
   .bDescriptorType    = TUSB_DESC_DEVICE_QUALIFIER,
   .bcdUSB             = USB_BCD,
diff --git a/hw/bsp/board.c b/hw/bsp/board.c
index 41e6eb1b8..476ec6733 100644
--- a/hw/bsp/board.c
+++ b/hw/bsp/board.c
@@ -51,7 +51,7 @@ int sys_read(int fhdl, char *buf, size_t count) TU_ATTR_USED;
 
 int sys_write(int fhdl, const char *buf, size_t count) {
   (void) fhdl;
-  SEGGER_RTT_Write(0, (const char *) buf, (int) count);
+  SEGGER_RTT_Write(0, buf, (int) count);
   return (int) count;
 }
 
@@ -111,16 +111,6 @@ int sys_read (int fhdl, char *buf, size_t count) {
 
 #endif
 
-//int _close(int fhdl) {
-//  (void) fhdl;
-//  return 0;
-//}
-
-//int _fstat(int file, struct stat *st) {
-//  memset(st, 0, sizeof(*st));
-//  st->st_mode = S_IFCHR;
-//}
-
 // Clang use picolibc
 #if defined(__clang__)
 static int cl_putc(char c, FILE *f) {
@@ -147,8 +137,8 @@ TU_ATTR_WEAK size_t board_get_unique_id(uint8_t id[], size_t max_len) {
   (void) max_len;
   // fixed serial string is 01234567889ABCDEF
   uint32_t* uid32 = (uint32_t*) (uintptr_t)id;
-  uid32[0] = 0x67452301;
-  uid32[1] = 0xEFCDAB89;
+  uid32[0] = 0x67452301u;
+  uid32[1] = 0xEFCDAB89u;
   return 8;
 }
 
diff --git a/hw/bsp/stm32h7/boards/stm32h743eval/board.h b/hw/bsp/stm32h7/boards/stm32h743eval/board.h
index cfffc7770..96bfc24e1 100644
--- a/hw/bsp/stm32h7/boards/stm32h743eval/board.h
+++ b/hw/bsp/stm32h7/boards/stm32h743eval/board.h
@@ -61,7 +61,7 @@ static board_pindef_t board_pindef[] = {
   { // LED
     .port = GPIOA,
     .pin_init = { .Pin = GPIO_PIN_4, .Mode = GPIO_MODE_OUTPUT_PP, .Pull = GPIO_PULLDOWN, .Speed = GPIO_SPEED_HIGH, .Alternate = 0 },
-    .active_state = 1
+    .active_state = 0
   },
   { // Button
     .port = GPIOC,
diff --git a/src/common/tusb_common.h b/src/common/tusb_common.h
index 50c1be2c6..dfa9299c1 100644
--- a/src/common/tusb_common.h
+++ b/src/common/tusb_common.h
@@ -131,7 +131,7 @@ TU_ATTR_ALWAYS_INLINE static inline int tu_memcpy_s(void *dest, size_t destsz, c
   }
 
   // For memcpy, src may be NULL only if count == 0. Reject otherwise.
-  if (src == NULL && count != 0) {
+  if (src == NULL && count != 0u) {
     return -1;
   }
 
diff --git a/src/common/tusb_debug.h b/src/common/tusb_debug.h
index 1d0c6f1ad..86517b9c9 100644
--- a/src/common/tusb_debug.h
+++ b/src/common/tusb_debug.h
@@ -58,8 +58,10 @@ void tu_print_mem(void const *buf, uint32_t count, uint8_t indent);
   #define tu_printf    printf
 #endif
 
-static inline void tu_print_buf(uint8_t const* buf, uint32_t bufsize) {
-  for(uint32_t i=0; i<bufsize; i++) tu_printf("%02X ", buf[i]);
+TU_ATTR_ALWAYS_INLINE static inline void tu_print_buf(uint8_t const* buf, uint32_t bufsize) {
+  for(uint32_t i=0; i<bufsize; i++) {
+    tu_printf("%02X ", buf[i]);
+  }
   tu_printf("\r\n");
 }
 
@@ -109,7 +111,9 @@ typedef struct {
 
 static inline const char* tu_lookup_find(tu_lookup_table_t const* p_table, uint32_t key) {
   for(uint16_t i=0; i<p_table->count; i++) {
-    if (p_table->items[i].key == key) { return p_table->items[i].data; }
+    if (p_table->items[i].key == key) {
+      return p_table->items[i].data;
+    }
   }
 
   // not found return the key value in hex
@@ -130,8 +134,6 @@ static inline const char* tu_lookup_find(tu_lookup_table_t const* p_table, uint3
   #define TU_LOG_FAILED()
 #endif
 
-// TODO replace all TU_LOGn with TU_LOG(n)
-
 #define TU_LOG0(...)
 #define TU_LOG0_MEM(...)
 #define TU_LOG0_BUF(...)
diff --git a/src/osal/osal.h b/src/osal/osal.h
index a33280425..8faa81b07 100644
--- a/src/osal/osal.h
+++ b/src/osal/osal.h
@@ -71,10 +71,9 @@ typedef void (*osal_task_func_t)( void * );
   #error OS is not supported yet
 #endif
 
-//--------------------------------------------------------------------+
-// OSAL Porting API
-// Should be implemented as static inline function in osal_port.h header
-/*
+/*--------------------------------------------------------------------
+  OSAL Porting API
+  Should be implemented as static inline function in osal_port.h header
    void osal_spin_init(osal_spinlock_t *ctx);
    void osal_spin_lock(osal_spinlock_t *ctx, bool in_isr)
    void osal_spin_unlock(osal_spinlock_t *ctx, bool in_isr);
@@ -83,7 +82,7 @@ typedef void (*osal_task_func_t)( void * );
    bool osal_semaphore_delete(osal_semaphore_t semd_hdl);
    bool osal_semaphore_post(osal_semaphore_t sem_hdl, bool in_isr);
    bool osal_semaphore_wait(osal_semaphore_t sem_hdl, uint32_t msec);
-   void osal_semaphore_reset(osal_semaphore_t sem_hdl); // TODO removed
+   void osal_semaphore_reset(osal_semaphore_t sem_hdl);
 
    osal_mutex_t osal_mutex_create(osal_mutex_def_t* mdef);
    bool osal_mutex_delete(osal_mutex_t mutex_hdl)
@@ -95,8 +94,8 @@ typedef void (*osal_task_func_t)( void * );
    bool osal_queue_receive(osal_queue_t qhdl, void* data, uint32_t msec);
    bool osal_queue_send(osal_queue_t qhdl, void const * data, bool in_isr);
    bool osal_queue_empty(osal_queue_t qhdl);
-*/
-//--------------------------------------------------------------------+
+--------------------------------------------------------------------------*/
+
 
 #ifdef __cplusplus
  }