stm32wb-dfu: add MSOS headers

The USB DFU example now shows how to automatically get the WinUSB driver assigned.

examples/boot/bootloader/stm32wb-dfu/src/main.rs

@@ -12,14 +12,17 @@ use embassy_stm32::rcc::WPAN_DEFAULT;
 use embassy_stm32::usb::Driver;
 use embassy_stm32::{bind_interrupts, peripherals, usb};
 use embassy_sync::blocking_mutex::Mutex;
-use embassy_usb::Builder;
+use embassy_usb::{msos, Builder};
 use embassy_usb_dfu::consts::DfuAttributes;
 use embassy_usb_dfu::{usb_dfu, Control, ResetImmediate};
 
 bind_interrupts!(struct Irqs {
     USB_LP => usb::InterruptHandler<peripherals::USB>;
 });
 
+// This is a randomly generated GUID to allow clients on Windows to find our device
+const DEVICE_INTERFACE_GUIDS: &[&str] = &["{EAA9A5DC-30BA-44BC-9232-606CDC875321}"];
+
 #[entry]
 fn main() -> ! {
     let mut config = embassy_stm32::Config::default();
@@ -62,6 +65,18 @@ fn main() -> ! {
             &mut control_buf,
         );
 
+        // We add MSOS headers so that the device automatically gets assigned the WinUSB driver on Windows.
+        // Otherwise users need to do this manually using a tool like Zadig.
+        //
+        // It seems it is important for the DFU class that these headers be on the Device level.
+        //
+        builder.msos_descriptor(msos::windows_version::WIN8_1, 2);
+        builder.msos_feature(msos::CompatibleIdFeatureDescriptor::new("WINUSB", ""));
+        builder.msos_feature(msos::RegistryPropertyFeatureDescriptor::new(
+            "DeviceInterfaceGUIDs",
+            msos::PropertyData::RegMultiSz(DEVICE_INTERFACE_GUIDS),
+        ));
+
         usb_dfu::<_, _, _, ResetImmediate, 4096>(&mut builder, &mut state);
 
         let mut dev = builder.build();