From e6caff3db3178d1663af427fa04b705efcf4e4f1 Mon Sep 17 00:00:00 2001
From: Dimitriy Ryazantcev <dimitriy.ryazantcev@gmail.com>
Date: Sun, 12 Mar 2023 22:29:34 +0200
Subject: [PATCH] windows: Get Bluetooth device Model Number String  instead of
 Device Name into product string (#500)

Use `Device Name` only if `Model Number String` is not available. This should better match what we have in  `USB_DEVICE_DESCRIPTOR.iProduct`

See [Bluetooth Device Information Service](https://www.bluetooth.com/specifications/specs/device-information-service-1-1/) spec for more info.
---
 windows/hid.c             | 58 +++++++++++++++++++++++----------------
 windows/hidapi_cfgmgr32.h |  1 +
 2 files changed, 35 insertions(+), 24 deletions(-)

diff --git a/windows/hid.c b/windows/hid.c
index 1b725b32c..5453faa15 100644
--- a/windows/hid.c
+++ b/windows/hid.c
@@ -409,32 +409,46 @@ static void* hid_internal_get_device_interface_property(const wchar_t* interface
 	return property_value;
 }
 
+/* HidD_GetProductString/HidD_GetManufacturerString/HidD_GetSerialNumberString is not working for BLE HID devices
+   Request this info via dev node properties instead.
+   https://docs.microsoft.com/answers/questions/401236/hidd-getproductstring-with-ble-hid-device.html
+*/
 static void hid_internal_get_ble_info(struct hid_device_info* dev, DEVINST dev_node)
 {
-	wchar_t *manufacturer_string, *serial_number, *product_string;
-	/* Manufacturer String */
-	manufacturer_string = hid_internal_get_devnode_property(dev_node, (const DEVPROPKEY*)&PKEY_DeviceInterface_Bluetooth_Manufacturer, DEVPROP_TYPE_STRING);
-	if (manufacturer_string) {
-		free(dev->manufacturer_string);
-		dev->manufacturer_string = manufacturer_string;
+	if (wcslen(dev->manufacturer_string) == 0) {
+		/* Manufacturer Name String (UUID: 0x2A29) */
+		wchar_t* manufacturer_string = hid_internal_get_devnode_property(dev_node, (const DEVPROPKEY*)&PKEY_DeviceInterface_Bluetooth_Manufacturer, DEVPROP_TYPE_STRING);
+		if (manufacturer_string) {
+			free(dev->manufacturer_string);
+			dev->manufacturer_string = manufacturer_string;
+		}
 	}
 
-	/* Serial Number String (MAC Address) */
-	serial_number = hid_internal_get_devnode_property(dev_node, (const DEVPROPKEY*)&PKEY_DeviceInterface_Bluetooth_DeviceAddress, DEVPROP_TYPE_STRING);
-	if (serial_number) {
-		free(dev->serial_number);
-		dev->serial_number = serial_number;
+	if (wcslen(dev->serial_number) == 0) {
+		/* Serial Number String (UUID: 0x2A25) */
+		wchar_t* serial_number = hid_internal_get_devnode_property(dev_node, (const DEVPROPKEY*)&PKEY_DeviceInterface_Bluetooth_DeviceAddress, DEVPROP_TYPE_STRING);
+		if (serial_number) {
+			free(dev->serial_number);
+			dev->serial_number = serial_number;
+		}
 	}
 
-	/* Get devnode grandparent to reach out Bluetooth LE device node */
-	if (CM_Get_Parent(&dev_node, dev_node, 0) != CR_SUCCESS)
-		return;
+	if (wcslen(dev->product_string) == 0) {
+		/* Model Number String (UUID: 0x2A24) */
+		wchar_t* product_string = hid_internal_get_devnode_property(dev_node, (const DEVPROPKEY*)&PKEY_DeviceInterface_Bluetooth_ModelNumber, DEVPROP_TYPE_STRING);
+		if (!product_string) {
+			DEVINST parent_dev_node = 0;
+			/* Fallback: Get devnode grandparent to reach out Bluetooth LE device node */
+			if (CM_Get_Parent(&parent_dev_node, dev_node, 0) == CR_SUCCESS) {
+				/* Device Name (UUID: 0x2A00) */
+				product_string = hid_internal_get_devnode_property(parent_dev_node, &DEVPKEY_NAME, DEVPROP_TYPE_STRING);
+			}
+		}
 
-	/* Product String */
-	product_string = hid_internal_get_devnode_property(dev_node, &DEVPKEY_NAME, DEVPROP_TYPE_STRING);
-	if (product_string) {
-		free(dev->product_string);
-		dev->product_string = product_string;
+		if (product_string) {
+			free(dev->product_string);
+			dev->product_string = product_string;
+		}
 	}
 }
 
@@ -527,12 +541,8 @@ static void hid_internal_get_info(const wchar_t* interface_path, struct hid_devi
 
 		/* Bluetooth LE devices */
 		if (wcsstr(compatible_id, L"BTHLEDEVICE") != NULL) {
-			/* HidD_GetProductString/HidD_GetManufacturerString/HidD_GetSerialNumberString is not working for BLE HID devices
-			   Request this info via dev node properties instead.
-			   https://docs.microsoft.com/answers/questions/401236/hidd-getproductstring-with-ble-hid-device.html */
-			hid_internal_get_ble_info(dev, dev_node);
-
 			dev->bus_type = HID_API_BUS_BLUETOOTH;
+			hid_internal_get_ble_info(dev, dev_node);
 			break;
 		}
 
diff --git a/windows/hidapi_cfgmgr32.h b/windows/hidapi_cfgmgr32.h
index 720906e3d..e73b15f69 100644
--- a/windows/hidapi_cfgmgr32.h
+++ b/windows/hidapi_cfgmgr32.h
@@ -63,6 +63,7 @@ static DEVPROPKEY DEVPKEY_Device_ContainerId = { { 0x8c7ed206, 0x3f8a, 0x4827, {
 // from propkey.h
 static PROPERTYKEY PKEY_DeviceInterface_Bluetooth_DeviceAddress = { { 0x2bd67d8b, 0x8beb, 0x48d5, {0x87, 0xe0, 0x6c, 0xda, 0x34, 0x28, 0x04, 0x0a} }, 1 }; // DEVPROP_TYPE_STRING
 static PROPERTYKEY PKEY_DeviceInterface_Bluetooth_Manufacturer = { { 0x2bd67d8b, 0x8beb, 0x48d5, {0x87, 0xe0, 0x6c, 0xda, 0x34, 0x28, 0x04, 0x0a} }, 4 }; // DEVPROP_TYPE_STRING
+static PROPERTYKEY PKEY_DeviceInterface_Bluetooth_ModelNumber = { { 0x2bd67d8b, 0x8beb, 0x48d5, {0x87, 0xe0, 0x6c, 0xda, 0x34, 0x28, 0x04, 0x0a} }, 5 }; // DEVPROP_TYPE_STRING
 
 #endif