Merge pull request #2593 from HiFiPhile/dcd_notif

cdc: add uart status notification support.

13 files changed, 214 insertions, 104 deletions

diff --git a/examples/device/cdc_dual_ports/src/main.c b/examples/device/cdc_dual_ports/src/main.c
index 63ae8a8c9..5a3e18358 100644
--- a/examples/device/cdc_dual_ports/src/main.c
+++ b/examples/device/cdc_dual_ports/src/main.c
@@ -98,27 +98,33 @@ void tud_umount_cb(void) {
   blink_interval_ms = BLINK_NOT_MOUNTED;
 }
 
-
 //--------------------------------------------------------------------+
 // USB CDC
 //--------------------------------------------------------------------+
 static void cdc_task(void) {
-  uint8_t itf;
-
-  for (itf = 0; itf < CFG_TUD_CDC; itf++) {
+  for (uint8_t itf = 0; itf < CFG_TUD_CDC; itf++) {
     // connected() check for DTR bit
     // Most but not all terminal client set this when making connection
     // if ( tud_cdc_n_connected(itf) )
     {
       if (tud_cdc_n_available(itf)) {
         uint8_t buf[64];
-
         uint32_t count = tud_cdc_n_read(itf, buf, sizeof(buf));
 
         // echo back to both serial ports
         echo_serial_port(0, buf, count);
         echo_serial_port(1, buf, count);
       }
+
+      // Press on-board button to send Uart status notification
+      static uint32_t btn_prev = 0;
+      static cdc_notify_uart_state_t uart_state = { .value = 0 };
+      const uint32_t btn = board_button_read();
+      if (!btn_prev && btn) {
+        uart_state.dsr ^= 1;
+        tud_cdc_notify_uart_state(&uart_state);
+      }
+      btn_prev = btn;
     }
   }
 }
diff --git a/examples/device/cdc_dual_ports/src/tusb_config.h b/examples/device/cdc_dual_ports/src/tusb_config.h
index 070f08ed1..7f7df3909 100644
--- a/examples/device/cdc_dual_ports/src/tusb_config.h
+++ b/examples/device/cdc_dual_ports/src/tusb_config.h
@@ -97,6 +97,8 @@
 #define CFG_TUD_MIDI              0
 #define CFG_TUD_VENDOR            0
 
+#define CFG_TUD_CDC_NOTIFY        1 // Enable use of notification endpoint
+
 // CDC FIFO size of TX and RX
 #define CFG_TUD_CDC_RX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)
 #define CFG_TUD_CDC_TX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)
diff --git a/examples/device/cdc_dual_ports/src/usb_descriptors.c b/examples/device/cdc_dual_ports/src/usb_descriptors.c
index 7776eb958..bbcb479f5 100644
--- a/examples/device/cdc_dual_ports/src/usb_descriptors.c
+++ b/examples/device/cdc_dual_ports/src/usb_descriptors.c
@@ -42,8 +42,7 @@
 //--------------------------------------------------------------------+
 // Device Descriptors
 //--------------------------------------------------------------------+
-tusb_desc_device_t const desc_device =
-{
+tusb_desc_device_t const desc_device = {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
     .bcdUSB             = USB_BCD,
@@ -68,16 +67,14 @@ tusb_desc_device_t const desc_device =
 
 // Invoked when received GET DEVICE DESCRIPTOR
 // Application return pointer to descriptor
-uint8_t const * tud_descriptor_device_cb(void)
-{
+uint8_t const *tud_descriptor_device_cb(void) {
   return (uint8_t const *) &desc_device;
 }
 
 //--------------------------------------------------------------------+
 // Configuration Descriptor
 //--------------------------------------------------------------------+
-enum
-{
+enum {
   ITF_NUM_CDC_0 = 0,
   ITF_NUM_CDC_0_DATA,
   ITF_NUM_CDC_1,
@@ -130,36 +127,32 @@ enum
   #define EPNUM_CDC_1_IN      0x84
 #endif
 
-uint8_t const desc_fs_configuration[] =
-{
+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),
 
   // 1st CDC: Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_0, 4, EPNUM_CDC_0_NOTIF, 8, EPNUM_CDC_0_OUT, EPNUM_CDC_0_IN, 64),
+  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_0, 4, EPNUM_CDC_0_NOTIF, 16, EPNUM_CDC_0_OUT, EPNUM_CDC_0_IN, 64),
 
   // 2nd CDC: Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_1, 4, EPNUM_CDC_1_NOTIF, 8, EPNUM_CDC_1_OUT, EPNUM_CDC_1_IN, 64),
+  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_1, 4, EPNUM_CDC_1_NOTIF, 16, EPNUM_CDC_1_OUT, EPNUM_CDC_1_IN, 64),
 };
 
 #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[] =
-{
+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),
 
   // 1st CDC: Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_0, 4, EPNUM_CDC_0_NOTIF, 8, EPNUM_CDC_0_OUT, EPNUM_CDC_0_IN, 512),
+  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_0, 4, EPNUM_CDC_0_NOTIF, 16, EPNUM_CDC_0_OUT, EPNUM_CDC_0_IN, 512),
 
   // 2nd CDC: Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_1, 4, EPNUM_CDC_1_NOTIF, 8, EPNUM_CDC_1_OUT, EPNUM_CDC_1_IN, 512),
+  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_1, 4, EPNUM_CDC_1_NOTIF, 16, EPNUM_CDC_1_OUT, EPNUM_CDC_1_IN, 512),
 };
 
 // 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 =
-{
+tusb_desc_device_qualifier_t const desc_device_qualifier = {
   .bLength            = sizeof(tusb_desc_device_t),
   .bDescriptorType    = TUSB_DESC_DEVICE,
   .bcdUSB             = USB_BCD,
@@ -177,34 +170,31 @@ tusb_desc_device_qualifier_t const desc_device_qualifier =
 // Application return pointer to descriptor, whose contents must exist long enough for transfer to complete.
 // device_qualifier descriptor describes information about a high-speed capable device that would
 // change if the device were operating at the other speed. If not highspeed capable stall this request.
-uint8_t const* tud_descriptor_device_qualifier_cb(void)
-{
-  return (uint8_t const*) &desc_device_qualifier;
+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
+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
-  return (tud_speed_get() == TUSB_SPEED_HIGH) ?  desc_fs_configuration : desc_hs_configuration;
+  return (tud_speed_get() == TUSB_SPEED_HIGH) ? desc_fs_configuration : desc_hs_configuration;
 }
 
-#endif // highspeed
+#endif// highspeed
 
 // Invoked when received GET CONFIGURATION DESCRIPTOR
 // Application return pointer to descriptor
 // Descriptor contents must exist long enough for transfer to complete
-uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
-{
+uint8_t const *tud_descriptor_configuration_cb(uint8_t index) {
   (void) index; // for multiple configurations
 
 #if TUD_OPT_HIGH_SPEED
   // Although we are highspeed, host may be fullspeed.
-  return (tud_speed_get() == TUSB_SPEED_HIGH) ?  desc_hs_configuration : desc_fs_configuration;
+  return (tud_speed_get() == TUSB_SPEED_HIGH) ? desc_hs_configuration : desc_fs_configuration;
 #else
   return desc_fs_configuration;
 #endif
@@ -223,8 +213,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
-{
+char const *string_desc_arr[] = {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
   "TinyUSB Device",              // 2: Product
@@ -254,14 +243,14 @@ uint16_t const *tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
       // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors.
       // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors
 
-      if ( !(index < sizeof(string_desc_arr) / sizeof(string_desc_arr[0])) ) return NULL;
+      if ( !(index < sizeof(string_desc_arr) / sizeof(string_desc_arr[0])) ) { return NULL; }
 
       const char *str = string_desc_arr[index];
 
       // Cap at max char
       chr_count = strlen(str);
       size_t const max_count = sizeof(_desc_str) / sizeof(_desc_str[0]) - 1; // -1 for string type
-      if ( chr_count > max_count ) chr_count = max_count;
+      if ( chr_count > max_count ) { chr_count = max_count; }
 
       // Convert ASCII string into UTF-16
       for ( size_t i = 0; i < chr_count; i++ ) {
@@ -272,6 +261,5 @@ uint16_t const *tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
 
   // first byte is length (including header), second byte is string type
   _desc_str[0] = (uint16_t) ((TUSB_DESC_STRING << 8) | (2 * chr_count + 2));
-
   return _desc_str;
 }
diff --git a/examples/device/cdc_msc/src/main.c b/examples/device/cdc_msc/src/main.c
index f36c910d7..5cd93e7dd 100644
--- a/examples/device/cdc_msc/src/main.c
+++ b/examples/device/cdc_msc/src/main.c
@@ -119,6 +119,16 @@ void cdc_task(void) {
       tud_cdc_write(buf, count);
       tud_cdc_write_flush();
     }
+
+    // Press on-board button to send Uart status notification
+    static uint32_t btn_prev = 0;
+    static cdc_notify_uart_state_t uart_state = { .value = 0 };
+    const uint32_t btn = board_button_read();
+    if (!btn_prev && btn) {
+      uart_state.dsr ^= 1;
+      tud_cdc_notify_uart_state(&uart_state);
+    }
+    btn_prev = btn;
   }
 }
 
diff --git a/examples/device/cdc_msc/src/tusb_config.h b/examples/device/cdc_msc/src/tusb_config.h
index 03e0e649c..811d464e9 100644
--- a/examples/device/cdc_msc/src/tusb_config.h
+++ b/examples/device/cdc_msc/src/tusb_config.h
@@ -87,7 +87,7 @@
 //--------------------------------------------------------------------
 
 #ifndef CFG_TUD_ENDPOINT0_SIZE
-#define CFG_TUD_ENDPOINT0_SIZE    64
+#define CFG_TUD_ENDPOINT0_SIZE   64
 #endif
 
 //------------- CLASS -------------//
@@ -97,6 +97,8 @@
 #define CFG_TUD_MIDI             0
 #define CFG_TUD_VENDOR           0
 
+#define CFG_TUD_CDC_NOTIFY        1 // Enable use of notification endpoint
+
 // CDC FIFO size of TX and RX
 #define CFG_TUD_CDC_RX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)
 #define CFG_TUD_CDC_TX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)
diff --git a/examples/device/cdc_msc/src/usb_descriptors.c b/examples/device/cdc_msc/src/usb_descriptors.c
index 4b6b88041..edcee0462 100644
--- a/examples/device/cdc_msc/src/usb_descriptors.c
+++ b/examples/device/cdc_msc/src/usb_descriptors.c
@@ -52,7 +52,6 @@ tusb_desc_device_t const desc_device = {
     .bDeviceClass       = TUSB_CLASS_MISC,
     .bDeviceSubClass    = MISC_SUBCLASS_COMMON,
     .bDeviceProtocol    = MISC_PROTOCOL_IAD,
-
     .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,
 
     .idVendor           = USB_VID,
@@ -131,7 +130,7 @@ uint8_t const desc_fs_configuration[] = {
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
     // Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-    TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, EPNUM_CDC_IN, 64),
+    TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 16, EPNUM_CDC_OUT, EPNUM_CDC_IN, 64),
 
     // Interface number, string index, EP Out & EP In address, EP size
     TUD_MSC_DESCRIPTOR(ITF_NUM_MSC, 5, EPNUM_MSC_OUT, EPNUM_MSC_IN, 64),
@@ -146,7 +145,7 @@ uint8_t const desc_hs_configuration[] = {
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
     // Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-    TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, EPNUM_CDC_IN, 512),
+    TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 16, EPNUM_CDC_OUT, EPNUM_CDC_IN, 512),
 
     // Interface number, string index, EP Out & EP In address, EP size
     TUD_MSC_DESCRIPTOR(ITF_NUM_MSC, 5, EPNUM_MSC_OUT, EPNUM_MSC_IN, 512),
@@ -197,7 +196,6 @@ uint8_t const *tud_descriptor_other_speed_configuration_cb(uint8_t index) {
 
 #endif // highspeed
 
-
 // Invoked when received GET CONFIGURATION DESCRIPTOR
 // Application return pointer to descriptor
 // Descriptor contents must exist long enough for transfer to complete
@@ -256,14 +254,14 @@ uint16_t const *tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
       // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors.
       // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors
 
-      if ( !(index < sizeof(string_desc_arr) / sizeof(string_desc_arr[0])) ) return NULL;
+      if ( !(index < sizeof(string_desc_arr) / sizeof(string_desc_arr[0])) ) { return NULL; }
 
       const char *str = string_desc_arr[index];
 
       // Cap at max char
       chr_count = strlen(str);
       size_t const max_count = sizeof(_desc_str) / sizeof(_desc_str[0]) - 1; // -1 for string type
-      if ( chr_count > max_count ) chr_count = max_count;
+      if ( chr_count > max_count ) { chr_count = max_count; }
 
       // Convert ASCII string into UTF-16
       for ( size_t i = 0; i < chr_count; i++ ) {
@@ -274,6 +272,5 @@ uint16_t const *tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
 
   // first byte is length (including header), second byte is string type
   _desc_str[0] = (uint16_t) ((TUSB_DESC_STRING << 8) | (2 * chr_count + 2));
-
   return _desc_str;
 }
diff --git a/examples/device/cdc_msc_freertos/src/main.c b/examples/device/cdc_msc_freertos/src/main.c
index 6fe964153..09ccc9bf3 100644
--- a/examples/device/cdc_msc_freertos/src/main.c
+++ b/examples/device/cdc_msc_freertos/src/main.c
@@ -189,6 +189,16 @@ void cdc_task(void *params) {
       }
 
       tud_cdc_write_flush();
+
+      // Press on-board button to send Uart status notification
+      static uint32_t btn_prev = 0;
+      static cdc_notify_uart_state_t uart_state = { .value = 0 };
+      const uint32_t btn = board_button_read();
+      if (!btn_prev && btn) {
+        uart_state.dsr ^= 1;
+        tud_cdc_notify_uart_state(&uart_state);
+      }
+      btn_prev = btn;
     }
 
     // For ESP32-Sx this delay is essential to allow idle how to run and reset watchdog
diff --git a/examples/device/cdc_msc_freertos/src/tusb_config.h b/examples/device/cdc_msc_freertos/src/tusb_config.h
index 71a0e985a..9cc3a18d1 100644
--- a/examples/device/cdc_msc_freertos/src/tusb_config.h
+++ b/examples/device/cdc_msc_freertos/src/tusb_config.h
@@ -104,6 +104,8 @@
 #define CFG_TUD_MIDI             0
 #define CFG_TUD_VENDOR           0
 
+#define CFG_TUD_CDC_NOTIFY        1 // Enable use of notification endpoint
+
 // CDC FIFO size of TX and RX
 #define CFG_TUD_CDC_RX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)
 #define CFG_TUD_CDC_TX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)
diff --git a/examples/device/cdc_msc_freertos/src/usb_descriptors.c b/examples/device/cdc_msc_freertos/src/usb_descriptors.c
index 405a57fe4..a55fa3675 100644
--- a/examples/device/cdc_msc_freertos/src/usb_descriptors.c
+++ b/examples/device/cdc_msc_freertos/src/usb_descriptors.c
@@ -52,7 +52,6 @@ tusb_desc_device_t const desc_device = {
     .bDeviceClass       = TUSB_CLASS_MISC,
     .bDeviceSubClass    = MISC_SUBCLASS_COMMON,
     .bDeviceProtocol    = MISC_PROTOCOL_IAD,
-
     .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,
 
     .idVendor           = USB_VID,
@@ -131,7 +130,7 @@ uint8_t const desc_fs_configuration[] =
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
   // Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, EPNUM_CDC_IN, 64),
+  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 16, EPNUM_CDC_OUT, EPNUM_CDC_IN, 64),
 
   // Interface number, string index, EP Out & EP In address, EP size
   TUD_MSC_DESCRIPTOR(ITF_NUM_MSC, 5, EPNUM_MSC_OUT, EPNUM_MSC_IN, 64),
@@ -147,7 +146,7 @@ uint8_t const desc_hs_configuration[] =
   TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
 
   // Interface number, string index, EP notification address and size, EP data address (out, in) and size.
-  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, EPNUM_CDC_IN, 512),
+  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 16, EPNUM_CDC_OUT, EPNUM_CDC_IN, 512),
 
   // Interface number, string index, EP Out & EP In address, EP size
   TUD_MSC_DESCRIPTOR(ITF_NUM_MSC, 5, EPNUM_MSC_OUT, EPNUM_MSC_IN, 512),
@@ -176,16 +175,14 @@ tusb_desc_device_qualifier_t const desc_device_qualifier =
 // Application return pointer to descriptor, whose contents must exist long enough for transfer to complete.
 // device_qualifier descriptor describes information about a high-speed capable device that would
 // change if the device were operating at the other speed. If not highspeed capable stall this request.
-uint8_t const* tud_descriptor_device_qualifier_cb(void)
-{
+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)
-{
+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
@@ -204,13 +201,12 @@ uint8_t const* tud_descriptor_other_speed_configuration_cb(uint8_t index)
 // Invoked when received GET CONFIGURATION DESCRIPTOR
 // Application return pointer to descriptor
 // Descriptor contents must exist long enough for transfer to complete
-uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
-{
+uint8_t const * tud_descriptor_configuration_cb(uint8_t index) {
   (void) index; // for multiple configurations
 
 #if TUD_OPT_HIGH_SPEED
   // Although we are highspeed, host may be fullspeed.
-  return (tud_speed_get() == TUSB_SPEED_HIGH) ?  desc_hs_configuration : desc_fs_configuration;
+  return (tud_speed_get() == TUSB_SPEED_HIGH) ? desc_hs_configuration : desc_fs_configuration;
 #else
   return desc_fs_configuration;
 #endif
@@ -229,8 +225,7 @@ enum {
 };
 
 // array of pointer to string descriptors
-char const *string_desc_arr[] =
-{
+char const *string_desc_arr[] = {
   (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
   "TinyUSB",                     // 1: Manufacturer
   "TinyUSB Device",              // 2: Product
@@ -261,14 +256,14 @@ uint16_t const *tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
       // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors.
       // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors
 
-      if ( !(index < sizeof(string_desc_arr) / sizeof(string_desc_arr[0])) ) return NULL;
+      if ( !(index < sizeof(string_desc_arr) / sizeof(string_desc_arr[0])) ) { return NULL; }
 
       const char *str = string_desc_arr[index];
 
       // Cap at max char
       chr_count = strlen(str);
       size_t const max_count = sizeof(_desc_str) / sizeof(_desc_str[0]) - 1; // -1 for string type
-      if ( chr_count > max_count ) chr_count = max_count;
+      if ( chr_count > max_count ) { chr_count = max_count; }
 
       // Convert ASCII string into UTF-16
       for ( size_t i = 0; i < chr_count; i++ ) {
@@ -279,6 +274,5 @@ uint16_t const *tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
 
   // first byte is length (including header), second byte is string type
   _desc_str[0] = (uint16_t) ((TUSB_DESC_STRING << 8) | (2 * chr_count + 2));
-
   return _desc_str;
 }
diff --git a/src/class/cdc/cdc.h b/src/class/cdc/cdc.h
index 9f3ace63c..10ba16a7c 100644
--- a/src/class/cdc/cdc.h
+++ b/src/class/cdc/cdc.h
@@ -221,18 +221,20 @@ typedef enum {
 // Management Element Notification (Notification Endpoint)
 //--------------------------------------------------------------------+
 
+#define CDC_REQ_TYPE_NOTIF 0xA1 ///< Direction IN; Type Class; Recipient Interface
+
 /// 6.3 Notification Codes
 typedef enum {
-  CDC_NOTIF_NETWORK_CONNECTION               = 0x00, ///< This notification allows the device to notify the host about network connection status.
-  CDC_NOTIF_RESPONSE_AVAILABLE               = 0x01, ///< This notification allows the device to notify the hostthat a response is available. This response can be retrieved with a subsequent \ref CDC_REQUEST_GET_ENCAPSULATED_RESPONSE request.
+  CDC_NOTIF_NETWORK_CONNECTION               = 0x00, // notify the host about network connection status.
+  CDC_NOTIF_RESPONSE_AVAILABLE               = 0x01, // notify the host that a response is available.
   CDC_NOTIF_AUX_JACK_HOOK_STATE              = 0x08,
   CDC_NOTIF_RING_DETECT                      = 0x09,
   CDC_NOTIF_SERIAL_STATE                     = 0x20,
   CDC_NOTIF_CALL_STATE_CHANGE                = 0x28,
   CDC_NOTIF_LINE_STATE_CHANGE                = 0x29,
-  CDC_NOTIF_CONNECTION_SPEED_CHANGE          = 0x2A, ///< This notification allows the device to inform the host-networking driver that a change in either the upstream or the downstream bit rate of the connection has occurred
+  CDC_NOTIF_CONNECTION_SPEED_CHANGE          = 0x2A, // notify the host-networking driver that a change in either the upstream or the downstream bit rate of the connection has occurred
   CDC_NOTIF_MDLM_SEMANTIC_MODEL_NOTIFICATION = 0x40,
-}cdc_notification_request_t;
+} cdc_notify_request_t;
 
 //--------------------------------------------------------------------+
 // Class Specific Functional Descriptor (Communication Interface)
@@ -243,8 +245,7 @@ TU_ATTR_PACKED_BEGIN
 TU_ATTR_BIT_FIELD_ORDER_BEGIN
 
 /// Header Functional Descriptor (Communication Interface)
-typedef struct TU_ATTR_PACKED
-{
+typedef struct TU_ATTR_PACKED {
   uint8_t bLength            ; ///< Size of this descriptor in bytes.
   uint8_t bDescriptorType    ; ///< Descriptor Type, must be Class-Specific
   uint8_t bDescriptorSubType ; ///< Descriptor SubType one of above CDC_FUNC_DESC_
@@ -252,8 +253,7 @@ typedef struct TU_ATTR_PACKED
 }cdc_desc_func_header_t;
 
 /// Union Functional Descriptor (Communication Interface)
-typedef struct TU_ATTR_PACKED
-{
+typedef struct TU_ATTR_PACKED {
   uint8_t bLength                  ; ///< Size of this descriptor in bytes.
   uint8_t bDescriptorType          ; ///< Descriptor Type, must be Class-Specific
   uint8_t bDescriptorSubType       ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
@@ -271,14 +271,13 @@ typedef struct TU_ATTR_PACKED
 }
 
 /// Country Selection Functional Descriptor (Communication Interface)
-typedef struct TU_ATTR_PACKED
-{
+typedef struct TU_ATTR_PACKED {
   uint8_t bLength             ; ///< Size of this descriptor in bytes.
   uint8_t bDescriptorType     ; ///< Descriptor Type, must be Class-Specific
   uint8_t bDescriptorSubType  ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
   uint8_t iCountryCodeRelDate ; ///< Index of a string giving the release date for the implemented ISO 3166 Country Codes.
   uint16_t wCountryCode       ; ///< Country code in the format as defined in [ISO3166], release date as specified inoffset 3 for the first supported country.
-}cdc_desc_func_country_selection_t;
+} cdc_desc_func_country_selection_t;
 
 #define cdc_desc_func_country_selection_n_t(no_country) \
   struct TU_ATTR_PACKED {            \
@@ -295,8 +294,7 @@ typedef struct TU_ATTR_PACKED
 
 /// \brief Call Management Functional Descriptor
 /// \details This functional descriptor describes the processing of calls for the Communications Class interface.
-typedef struct TU_ATTR_PACKED
-{
+typedef struct TU_ATTR_PACKED {
   uint8_t bLength            ; ///< Size of this descriptor in bytes.
   uint8_t bDescriptorType    ; ///< Descriptor Type, must be Class-Specific
   uint8_t bDescriptorSubType ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
@@ -310,8 +308,7 @@ typedef struct TU_ATTR_PACKED
   uint8_t bDataInterface;
 }cdc_desc_func_call_management_t;
 
-typedef struct TU_ATTR_PACKED
-{
+typedef struct TU_ATTR_PACKED {
   uint8_t support_comm_request                    : 1; ///< Device supports the request combination of Set_Comm_Feature, Clear_Comm_Feature, and Get_Comm_Feature.
   uint8_t support_line_request                    : 1; ///< Device supports the request combination of Set_Line_Coding, Set_Control_Line_State, Get_Line_Coding, and the notification Serial_State.
   uint8_t support_send_break                      : 1; ///< Device supports the request Send_Break
@@ -323,8 +320,7 @@ TU_VERIFY_STATIC(sizeof(cdc_acm_capability_t) == 1, "mostly problem with compile
 
 /// Abstract Control Management Functional Descriptor
 /// This functional descriptor describes the commands supported by by the Communications Class interface with SubClass code of \ref CDC_COMM_SUBCLASS_ABSTRACT_CONTROL_MODEL
-typedef struct TU_ATTR_PACKED
-{
+typedef struct TU_ATTR_PACKED {
   uint8_t bLength                  ; ///< Size of this descriptor in bytes.
   uint8_t bDescriptorType          ; ///< Descriptor Type, must be Class-Specific
   uint8_t bDescriptorSubType       ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
@@ -333,8 +329,7 @@ typedef struct TU_ATTR_PACKED
 
 /// \brief Direct Line Management Functional Descriptor
 /// \details This functional descriptor describes the commands supported by the Communications Class interface with SubClass code of \ref CDC_FUNC_DESC_DIRECT_LINE_MANAGEMENT
-typedef struct TU_ATTR_PACKED
-{
+typedef struct TU_ATTR_PACKED {
   uint8_t bLength            ; ///< Size of this descriptor in bytes.
   uint8_t bDescriptorType    ; ///< Descriptor Type, must be Class-Specific
   uint8_t bDescriptorSubType ; ///< Descriptor SubType one of above CDC_FUCN_DESC_
@@ -396,8 +391,7 @@ typedef struct TU_ATTR_PACKED
 }cdc_desc_func_telephone_call_state_reporting_capabilities_t;
 
 // TODO remove
-static inline uint8_t cdc_functional_desc_typeof(uint8_t const * p_desc)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint8_t cdc_functional_desc_typeof(uint8_t const * p_desc) {
   return p_desc[2];
 }
 
@@ -414,7 +408,7 @@ typedef struct TU_ATTR_PACKED {
 TU_VERIFY_STATIC(sizeof(cdc_line_coding_t) == 7, "size is not correct");
 
 typedef union TU_ATTR_PACKED {
-  struct {
+  struct TU_ATTR_PACKED {
     uint8_t dtr : 1;
     uint8_t rts : 1;
     uint8_t     : 6;
@@ -424,6 +418,48 @@ typedef union TU_ATTR_PACKED {
 
 TU_VERIFY_STATIC(sizeof(cdc_line_control_state_t) == 1, "size is not correct");
 
+//--------------------------------------------------------------------+
+// Notifications
+//--------------------------------------------------------------------+
+// PSTN 1.2 section 6.5.4 table 31
+typedef union TU_ATTR_PACKED {
+  struct TU_ATTR_PACKED {
+    uint16_t bRxCarrier  : 1; // DCD
+    uint16_t bTxCarrier  : 1; // DSR
+    uint16_t bBreak      : 1; // Break Detected
+    uint16_t bRingSignal : 1;
+    uint16_t bFraming    : 1;
+    uint16_t bParity     : 1;
+    uint16_t bOverRun    : 1;
+    uint16_t             : 9;
+  };
+  struct TU_ATTR_PACKED {
+    uint16_t dcd : 1;
+    uint16_t dsr : 1;
+    uint16_t brk : 1;
+    uint16_t     :13;
+  };
+  uint16_t value;
+} cdc_notify_uart_state_t;
+
+TU_VERIFY_STATIC(sizeof(cdc_notify_uart_state_t) == 2, "size is not correct");
+
+// CDC 1.2 section 6.3.3 table 21
+typedef struct TU_ATTR_PACKED {
+  uint32_t upstream_bitrate;
+  uint32_t downstream_bitrate;
+} cdc_notify_conn_speed_change_t;
+
+typedef struct TU_ATTR_PACKED {
+  tusb_control_request_t request;
+  union {
+    cdc_notify_uart_state_t serial_state;
+    cdc_notify_conn_speed_change_t conn_speed_change;
+  };
+} cdc_notify_msg_t;
+
+TU_VERIFY_STATIC(sizeof(cdc_notify_msg_t) == 16, "size is not correct");
+
 TU_ATTR_PACKED_END  // End of all packed definitions
 TU_ATTR_BIT_FIELD_ORDER_END
 
diff --git a/src/class/cdc/cdc_device.c b/src/class/cdc/cdc_device.c
index 4d19adeb4..4e4e01eaf 100644
--- a/src/class/cdc/cdc_device.c
+++ b/src/class/cdc/cdc_device.c
@@ -46,13 +46,13 @@
 #define BULK_PACKET_SIZE (TUD_OPT_HIGH_SPEED ? 512 : 64)
 
 typedef struct {
+  uint8_t rhport;
   uint8_t itf_num;
-  uint8_t ep_notif;
   uint8_t ep_in;
   uint8_t ep_out;
 
-  // Bit 0:  DTR (Data Terminal Ready), Bit 1: RTS (Request to Send)
-  uint8_t line_state;
+  uint8_t ep_notify;
+  uint8_t line_state; // Bit 0: DTR, Bit 1: RTS
 
   /*------------- From this point, data is not cleared by bus reset -------------*/
   char wanted_char;
@@ -74,6 +74,10 @@ typedef struct {
 typedef struct {
   TUD_EPBUF_DEF(epout, CFG_TUD_CDC_EP_BUFSIZE);
   TUD_EPBUF_DEF(epin, CFG_TUD_CDC_EP_BUFSIZE);
+
+  #if CFG_TUD_CDC_NOTIFY
+  TUD_EPBUF_TYPE_DEF(cdc_notify_msg_t, epnotify);
+  #endif
 } cdcd_epbuf_t;
 
 //--------------------------------------------------------------------+
@@ -101,7 +105,7 @@ static bool _prep_out_transaction(uint8_t itf) {
   TU_VERIFY(available >= CFG_TUD_CDC_EP_BUFSIZE);
 
   // claim endpoint
-  TU_VERIFY(usbd_edpt_claim(rhport, p_cdc->ep_out));
+  TU_VERIFY(usbd_edpt_claim(p_cdc->rhport, p_cdc->ep_out));
 
   // fifo can be changed before endpoint is claimed
   available = tu_fifo_remaining(&p_cdc->rx_ff);
@@ -110,7 +114,7 @@ static bool _prep_out_transaction(uint8_t itf) {
     return usbd_edpt_xfer(rhport, p_cdc->ep_out, p_epbuf->epout, CFG_TUD_CDC_EP_BUFSIZE);
   } else {
     // Release endpoint since we don't make any transfer
-    usbd_edpt_release(rhport, p_cdc->ep_out);
+    usbd_edpt_release(p_cdc->rhport, p_cdc->ep_out);
     return false;
   }
 }
@@ -118,7 +122,6 @@ static bool _prep_out_transaction(uint8_t itf) {
 //--------------------------------------------------------------------+
 // APPLICATION API
 //--------------------------------------------------------------------+
-
 bool tud_cdc_configure(const tud_cdc_configure_t* driver_cfg) {
   TU_VERIFY(driver_cfg);
   _cdcd_cfg = *driver_cfg;
@@ -142,6 +145,42 @@ void tud_cdc_n_get_line_coding(uint8_t itf, cdc_line_coding_t* coding) {
   (*coding) = _cdcd_itf[itf].line_coding;
 }
 
+#if CFG_TUD_CDC_NOTIFY
+bool tud_cdc_n_notify_uart_state (uint8_t itf, const cdc_notify_uart_state_t *state) {
+  cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
+  cdcd_epbuf_t* p_epbuf = &_cdcd_epbuf[itf];
+  TU_VERIFY(tud_ready() && p_cdc->ep_notify != 0);
+  TU_VERIFY(usbd_edpt_claim(p_cdc->rhport, p_cdc->ep_notify));
+
+  cdc_notify_msg_t* notify_msg = &p_epbuf->epnotify;
+  notify_msg->request.bmRequestType = CDC_REQ_TYPE_NOTIF;
+  notify_msg->request.bRequest = CDC_NOTIF_SERIAL_STATE;
+  notify_msg->request.wValue = 0;
+  notify_msg->request.wIndex = p_cdc->itf_num;
+  notify_msg->request.wLength = sizeof(cdc_notify_uart_state_t);
+  notify_msg->serial_state = *state;
+
+  return usbd_edpt_xfer(p_cdc->rhport, p_cdc->ep_notify, (uint8_t *)notify_msg, 8 + sizeof(cdc_notify_uart_state_t));
+}
+
+bool tud_cdc_n_notify_conn_speed_change(uint8_t itf, const cdc_notify_conn_speed_change_t* conn_speed_change) {
+  cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
+  cdcd_epbuf_t* p_epbuf = &_cdcd_epbuf[itf];
+  TU_VERIFY(tud_ready() && p_cdc->ep_notify != 0);
+  TU_VERIFY(usbd_edpt_claim(p_cdc->rhport, p_cdc->ep_notify));
+
+  cdc_notify_msg_t* notify_msg = &p_epbuf->epnotify;
+  notify_msg->request.bmRequestType = CDC_REQ_TYPE_NOTIF;
+  notify_msg->request.bRequest = CDC_NOTIF_CONNECTION_SPEED_CHANGE;
+  notify_msg->request.wValue = 0;
+  notify_msg->request.wIndex = p_cdc->itf_num;
+  notify_msg->request.wLength = sizeof(cdc_notify_conn_speed_change_t);
+  notify_msg->conn_speed_change = *conn_speed_change;
+
+  return usbd_edpt_xfer(p_cdc->rhport, p_cdc->ep_notify, (uint8_t *)notify_msg, 8 + sizeof(cdc_notify_conn_speed_change_t));
+}
+#endif
+
 void tud_cdc_n_set_wanted_char(uint8_t itf, char wanted) {
   _cdcd_itf[itf].wanted_char = wanted;
 }
@@ -192,30 +231,25 @@ uint32_t tud_cdc_n_write(uint8_t itf, const void* buffer, uint32_t bufsize) {
 uint32_t tud_cdc_n_write_flush(uint8_t itf) {
   cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
   cdcd_epbuf_t* p_epbuf = &_cdcd_epbuf[itf];
-
-  // Skip if usb is not ready yet
-  TU_VERIFY(tud_ready(), 0);
+  TU_VERIFY(tud_ready(), 0); // Skip if usb is not ready yet
 
   // No data to send
   if (!tu_fifo_count(&p_cdc->tx_ff)) {
     return 0;
   }
 
-  const uint8_t rhport = 0;
-
-  // Claim the endpoint
-  TU_VERIFY(usbd_edpt_claim(rhport, p_cdc->ep_in), 0);
+  TU_VERIFY(usbd_edpt_claim(p_cdc->rhport, p_cdc->ep_in), 0); // Claim the endpoint
 
   // Pull data from FIFO
   const uint16_t count = tu_fifo_read_n(&p_cdc->tx_ff, p_epbuf->epin, CFG_TUD_CDC_EP_BUFSIZE);
 
   if (count) {
-    TU_ASSERT(usbd_edpt_xfer(rhport, p_cdc->ep_in, p_epbuf->epin, count), 0);
+    TU_ASSERT(usbd_edpt_xfer(p_cdc->rhport, p_cdc->ep_in, p_epbuf->epin, count), 0);
     return count;
   } else {
     // Release endpoint since we don't make any transfer
     // Note: data is dropped if terminal is not connected
-    usbd_edpt_release(rhport, p_cdc->ep_in);
+    usbd_edpt_release(p_cdc->rhport, p_cdc->ep_in);
     return 0;
   }
 }
@@ -319,6 +353,7 @@ uint16_t cdcd_open(uint8_t rhport, const tusb_desc_interface_t* itf_desc, uint16
   TU_ASSERT(cdc_id < CFG_TUD_CDC, 0);
 
   //------------- Control Interface -------------//
+  p_cdc->rhport = rhport;
   p_cdc->itf_num = itf_desc->bInterfaceNumber;
 
   uint16_t drv_len = sizeof(tusb_desc_interface_t);
@@ -333,9 +368,8 @@ uint16_t cdcd_open(uint8_t rhport, const tusb_desc_interface_t* itf_desc, uint16
   if (TUSB_DESC_ENDPOINT == tu_desc_type(p_desc)) {
     // notification endpoint
     const tusb_desc_endpoint_t* desc_ep = (const tusb_desc_endpoint_t*) p_desc;
-
     TU_ASSERT(usbd_edpt_open(rhport, desc_ep), 0);
-    p_cdc->ep_notif = desc_ep->bEndpointAddress;
+    p_cdc->ep_notify = desc_ep->bEndpointAddress;
 
     drv_len += tu_desc_len(p_desc);
     p_desc = tu_desc_next(p_desc);
@@ -455,7 +489,7 @@ bool cdcd_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_
   // Identify which interface to use
   for (itf = 0; itf < CFG_TUD_CDC; itf++) {
     p_cdc = &_cdcd_itf[itf];
-    if ((ep_addr == p_cdc->ep_out) || (ep_addr == p_cdc->ep_in)) {
+    if ((ep_addr == p_cdc->ep_out) || (ep_addr == p_cdc->ep_in) || (ep_addr == p_cdc->ep_notify)) {
       break;
     }
   }
@@ -504,7 +538,12 @@ bool cdcd_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_
     }
   }
 
-  // nothing to do with notif endpoint for now
+  // Sent notification to host
+  if (ep_addr == p_cdc->ep_notify) {
+    if (tud_cdc_notify_complete_cb) {
+      tud_cdc_notify_complete_cb(itf);
+    }
+  }
 
   return true;
 }
diff --git a/src/class/cdc/cdc_device.h b/src/class/cdc/cdc_device.h
index b653ebd74..a34e07e1d 100644
--- a/src/class/cdc/cdc_device.h
+++ b/src/class/cdc/cdc_device.h
@@ -32,6 +32,10 @@
 //--------------------------------------------------------------------+
 // Class Driver Configuration
 //--------------------------------------------------------------------+
+#ifndef CFG_TUD_CDC_NOTIFY
+  #define CFG_TUD_CDC_NOTIFY    0
+#endif
+
 #if !defined(CFG_TUD_CDC_EP_BUFSIZE) && defined(CFG_TUD_CDC_EPSIZE)
   #warning CFG_TUD_CDC_EPSIZE is renamed to CFG_TUD_CDC_EP_BUFSIZE, please update to use the new name
   #define CFG_TUD_CDC_EP_BUFSIZE    CFG_TUD_CDC_EPSIZE
@@ -126,6 +130,23 @@ uint32_t tud_cdc_n_write_available(uint8_t itf);
 // Clear the transmit FIFO
 bool tud_cdc_n_write_clear(uint8_t itf);
 
+
+#if CFG_TUD_CDC_NOTIFY
+// Send UART status notification: DCD, DSR etc ..
+bool tud_cdc_n_notify_uart_state(uint8_t itf, const cdc_notify_uart_state_t *state);
+
+// Send connection speed change notification
+bool tud_cdc_n_notify_conn_speed_change(uint8_t itf, const cdc_notify_conn_speed_change_t* conn_speed_change);
+
+TU_ATTR_ALWAYS_INLINE static inline bool tud_cdc_notify_uart_state(const cdc_notify_uart_state_t* state) {
+ return tud_cdc_n_notify_uart_state(0, state);
+}
+
+TU_ATTR_ALWAYS_INLINE static inline bool tud_cdc_notify_conn_speed_change(const cdc_notify_conn_speed_change_t* conn_speed_change) {
+  return tud_cdc_n_notify_conn_speed_change(0, conn_speed_change);
+}
+#endif
+
 //--------------------------------------------------------------------+
 // Application API (Single Port)
 //--------------------------------------------------------------------+
@@ -195,7 +216,7 @@ TU_ATTR_ALWAYS_INLINE static inline bool tud_cdc_write_clear(void) {
 }
 
 //--------------------------------------------------------------------+
-// Application Callback API (weak is optional)
+// Application Callback API
 //--------------------------------------------------------------------+
 
 // Invoked when received new data
@@ -207,6 +228,9 @@ TU_ATTR_WEAK void tud_cdc_rx_wanted_cb(uint8_t itf, char wanted_char);
 // Invoked when a TX is complete and therefore space becomes available in TX buffer
 TU_ATTR_WEAK void tud_cdc_tx_complete_cb(uint8_t itf);
 
+// Invoked when a notification is sent to host
+TU_ATTR_WEAK void tud_cdc_notify_complete_cb(uint8_t itf);
+
 // Invoked when line state DTR & RTS are changed via SET_CONTROL_LINE_STATE
 TU_ATTR_WEAK void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts);
 
diff --git a/src/device/usbd.h b/src/device/usbd.h
index de6007fb3..e5a848809 100644
--- a/src/device/usbd.h
+++ b/src/device/usbd.h
@@ -244,7 +244,7 @@ bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_requ
   /* CDC Union */\
   5, TUSB_DESC_CS_INTERFACE, CDC_FUNC_DESC_UNION, _itfnum, (uint8_t)((_itfnum) + 1),\
   /* Endpoint Notification */\
-  7, TUSB_DESC_ENDPOINT, _ep_notif, TUSB_XFER_INTERRUPT, U16_TO_U8S_LE(_ep_notif_size), 16,\
+  7, TUSB_DESC_ENDPOINT, _ep_notif, TUSB_XFER_INTERRUPT, U16_TO_U8S_LE(_ep_notif_size), 1,\
   /* CDC Data Interface */\
   9, TUSB_DESC_INTERFACE, (uint8_t)((_itfnum)+1), 0, 2, TUSB_CLASS_CDC_DATA, 0, 0, 0,\
   /* Endpoint Out */\