Merge pull request #32 from jonasblixt/msft-usb

drivers/usb/usbd: Add Microsoft OS Descriptors
jonasblixt · Dec 5, 2023 · d4de331 · d4de331
2 parents 9079917 + 506d3bf
commit d4de331
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diff --git a/include/drivers/usb/usbd.h b/include/drivers/usb/usbd.h
@@ -140,6 +140,27 @@ struct usb_endpoint_descriptor {
     uint8_t bInterval; // Interval for polling endpoint for data transfers
 } __attribute__((packed));
 
+struct usb_msft_os_descriptor {
+    uint8_t bLength;
+    uint8_t bDescriptorType;
+    uint8_t signature[14];
+    uint8_t bVendorCode;
+    uint8_t bPad;
+} __attribute__((packed));
+
+struct usb_msft_comp_id_feature {
+    uint32_t length;
+    uint8_t bcdVersion[2];
+    uint16_t wCompIDidx;
+    uint8_t bNumSel;
+    uint8_t rz1[7];
+    uint8_t bIfaceNo;
+    uint8_t rz2;
+    uint8_t compatibleId[8];
+    uint8_t subCompatibleId[8];
+    uint8_t rz3[6];
+} __attribute__((packed));
+
 struct usbd_descriptors {
     const struct usb_language_descriptor language;
     const struct usb_qualifier_descriptor qualifier;

diff --git a/src/drivers/usb/usbd.c b/src/drivers/usb/usbd.c
@@ -21,11 +21,49 @@
 #define USB_SET_FEATURE       0x0003
 #define USB_SET_ADDRESS       0x0005
 #define USB_GET_STATUS        0x8000
+#define USB_GET_VENDOR        0xc001
 
 static const struct usbd_hal_ops *hal_ops;
 static const struct usbd_cls_config *cls_config;
 static bool enumerated;
 
+/* Microsoft OS Descriptor
+ *
+ * When a new USB device enumerates on Windows the system will ask for string
+ * descriptor 0xEE, Which is Windows specific, if the string descriptor contains
+ * 'MSFT100' it will issue a vendor specific request for a 'Microsoft Compatible ID Feature
+ * Descriptor'.
+ *
+ * With these two in place Windows will automatically bind the device to WinUSB and
+ * in turn we can use libusb directly.
+ *
+ * Historically this was handled by the windows binary installer that bundeled
+ * libwdi.
+ *
+ * It's explained in greater detail here:
+ *     https://github.com/pbatard/libwdi/wiki/WCID-Devices
+ */
+static const struct usb_msft_os_descriptor msft_os_descriptor = {
+    .bLength = 18,
+    .bDescriptorType = 3,
+    .signature = { 0x4D, 0x00, 0x53, 0x00, 0x46, 0x00, 0x54, 0x00, 0x31, 0x00, 0x30, 0x00, 0x30, 0x00, },
+    .bVendorCode = 1,
+    .bPad = 0,
+};
+
+static const struct usb_msft_comp_id_feature msft_comp_id_feature = {
+    .length = 40,
+    .bcdVersion = { 0x00, 0x01 },
+    .wCompIDidx = 4,
+    .bNumSel = 1,
+    .rz1 = { 0 },
+    .bIfaceNo = 0,
+    .rz2 = 0,
+    .compatibleId = { 0x57, 0x49, 0x4E, 0x55, 0x53, 0x42, 0x00, 0x00, },
+    .subCompatibleId = { 0 },
+    .rz3 = { 0 },
+};
+
 static int usbd_enumerate(struct usb_setup_packet *setup);
 
 const char *ep_to_str(usb_ep_t ep)
@@ -126,6 +164,10 @@ static int usbd_enumerate(struct usb_setup_packet *setup)
             if (str_desc_idx == 0) {
                 length = MIN(setup->wLength, (uint16_t)sizeof(cls_config->desc->language));
                 rc = ep0_tx(&cls_config->desc->language, length);
+            } else if (str_desc_idx == 0xee) {
+                /* Microsoft OS Descriptor */
+                length = MIN(setup->wLength, (uint16_t)sizeof(msft_os_descriptor));
+                rc = ep0_tx(&msft_os_descriptor, length);
             } else {
                 struct usb_string_descriptor *str_desc =
                     cls_config->get_string_descriptor(str_desc_idx);
@@ -184,6 +226,13 @@ static int usbd_enumerate(struct usb_setup_packet *setup)
         LOG_DBG("Get status");
         rc = ep0_tx(&device_status, sizeof(device_status));
     } break;
+    case USB_GET_VENDOR: {
+        LOG_DBG("Get vendor specific descriptor");
+        if (setup->wIndex == 0x04) {
+            length = MIN(setup->wLength, (uint16_t)sizeof(msft_comp_id_feature));
+            rc = ep0_tx(&msft_comp_id_feature, length);
+        }
+    } break;
     default: {
         LOG_ERR("EP0 Unhandled request %x", request);
         LOG_ERR(" bRequestType = 0x%x", setup->bRequestType);