From a46addba7b740123d2de2d1c48d39212b0914d49 Mon Sep 17 00:00:00 2001
From: will-v-pi <108662275+will-v-pi@users.noreply.github.com>
Date: Sat, 24 Aug 2024 20:54:44 +0100
Subject: [PATCH] Fix stdio_usb with reset interface disabled on Windows
 (#1857)

* Only use bcdUSB = 0x0200 with MS_OS_20 descriptor enabled

* Add comment
---
 src/rp2_common/pico_stdio_usb/stdio_usb_descriptors.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/rp2_common/pico_stdio_usb/stdio_usb_descriptors.c b/src/rp2_common/pico_stdio_usb/stdio_usb_descriptors.c
index 7ecfdffe7..2f6e75877 100644
--- a/src/rp2_common/pico_stdio_usb/stdio_usb_descriptors.c
+++ b/src/rp2_common/pico_stdio_usb/stdio_usb_descriptors.c
@@ -92,7 +92,15 @@
 static const tusb_desc_device_t usbd_desc_device = {
     .bLength = sizeof(tusb_desc_device_t),
     .bDescriptorType = TUSB_DESC_DEVICE,
+// On Windows, if bcdUSB = 0x210 then a Microsoft OS 2.0 descriptor is required, else the device won't be detected
+// This is only needed for driverless access to the reset interface - the CDC interface doesn't require these descriptors
+// for driverless access, but will still not work if bcdUSB = 0x210 and no descriptor is provided. Therefore always
+// use bcdUSB = 0x200 if the Microsoft OS 2.0 descriptor isn't enabled
+#if PICO_STDIO_USB_ENABLE_RESET_VIA_VENDOR_INTERFACE && PICO_STDIO_USB_RESET_INTERFACE_SUPPORT_MS_OS_20_DESCRIPTOR
     .bcdUSB = 0x0210,
+#else
+    .bcdUSB = 0x0200,
+#endif
     .bDeviceClass = TUSB_CLASS_MISC,
     .bDeviceSubClass = MISC_SUBCLASS_COMMON,
     .bDeviceProtocol = MISC_PROTOCOL_IAD,