2 files changed, 21 insertions, 14 deletions

diff --git a/embassy-usb/src/builder.rs b/embassy-usb/src/builder.rs
index 28a449a9f..8d6d06a6b 100644
--- a/embassy-usb/src/builder.rs
+++ b/embassy-usb/src/builder.rs
@@ -8,6 +8,13 @@ use crate::types::{InterfaceNumber, StringIndex};
 use crate::{Handler, Interface, UsbDevice, MAX_INTERFACE_COUNT, STRING_INDEX_CUSTOM_START};
 
 #[derive(Debug, Copy, Clone)]
+/// Allows Configuring the Bcd USB version below 2.1
+pub enum BcdUsbVersion {
+    Two = 0x0200,
+    TwoOne = 0x0210,
+}
+
+#[derive(Debug, Copy, Clone)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[non_exhaustive]
 /// Configuration used when creating [`UsbDevice`].
@@ -18,7 +25,7 @@ pub struct Config<'a> {
     /// Device BCD USB version.
     ///
     /// Default: `0x0210` ("2.1")
-    pub bcd_usb: u16,
+    pub bcd_usb: BcdUsbVersion,
 
     /// Device class code assigned by USB.org. Set to `0xff` for vendor-specific
     /// devices that do not conform to any class.
@@ -113,7 +120,7 @@ impl<'a> Config<'a> {
             vendor_id: vid,
             product_id: pid,
             device_release: 0x0010,
-            bcd_usb: 0x0210,
+            bcd_usb: BcdUsbVersion::TwoOne,
             manufacturer: None,
             product: None,
             serial_number: None,
diff --git a/embassy-usb/src/descriptor.rs b/embassy-usb/src/descriptor.rs
index 09ce50951..51cd2b39a 100644
--- a/embassy-usb/src/descriptor.rs
+++ b/embassy-usb/src/descriptor.rs
@@ -326,11 +326,11 @@ pub(crate) fn device_descriptor(config: &Config) -> [u8; 18] {
         18,   // bLength
         0x01, // bDescriptorType
         config.bcd_usb as u8,
-        (config.bcd_usb >> 8) as u8, // bcdUSB
-        config.device_class,         // bDeviceClass
-        config.device_sub_class,     // bDeviceSubClass
-        config.device_protocol,      // bDeviceProtocol
-        config.max_packet_size_0,    // bMaxPacketSize0
+        (config.bcd_usb as u16 >> 8) as u8, // bcdUSB
+        config.device_class,                // bDeviceClass
+        config.device_sub_class,            // bDeviceSubClass
+        config.device_protocol,             // bDeviceProtocol
+        config.max_packet_size_0,           // bMaxPacketSize0
         config.vendor_id as u8,
         (config.vendor_id >> 8) as u8, // idVendor
         config.product_id as u8,
@@ -353,13 +353,13 @@ pub(crate) fn device_qualifier_descriptor(config: &Config) -> [u8; 10] {
         10,   // bLength
         0x06, // bDescriptorType
         0x10,
-        (config.bcd_usb >> 8) as u8, // bcdUSB
-        config.device_class,         // bDeviceClass
-        config.device_sub_class,     // bDeviceSubClass
-        config.device_protocol,      // bDeviceProtocol
-        config.max_packet_size_0,    // bMaxPacketSize0
-        1,                           // bNumConfigurations
-        0,                           // Reserved
+        (config.bcd_usb as u16 >> 8) as u8, // bcdUSB
+        config.device_class,                // bDeviceClass
+        config.device_sub_class,            // bDeviceSubClass
+        config.device_protocol,             // bDeviceProtocol
+        config.max_packet_size_0,           // bMaxPacketSize0
+        1,                                  // bNumConfigurations
+        0,                                  // Reserved
     ]
 }