dev: deduce product name from class if string descriptors are unavail…

…able JIRA: RTOS-937
phoenix-rtos · Jan 10, 2025 · 864d4f9 · 864d4f9
1 parent c291f77
commit 864d4f9
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Showing 2 changed files with 62 additions and 4 deletions.
diff --git a/libusb/usb.h b/libusb/usb.h
@@ -59,6 +59,7 @@
 #define CLASS_REQ_SET_CONTROL_LINE_STATE 0x22
 
 /* class codes */
+#define USB_CLASS_HID          0x3
 #define USB_CLASS_MASS_STORAGE 0x8
 #define USB_CLASS_HUB          0x9
 

diff --git a/usb/dev.c b/usb/dev.c
@@ -372,14 +372,61 @@ static int usb_getStringDesc(usb_dev_t *dev, char **buf, int index)
 }
 
 
+static void usb_guessProductString(usb_dev_t *dev)
+{
+	switch (dev->desc.bDeviceClass) {
+		case USB_CLASS_HID:
+			dev->product = "USB HID";
+			break;
+		case USB_CLASS_HUB:
+			switch (dev->desc.bDeviceProtocol) {
+				case USB_HUB_PROTO_ROOT:
+					dev->product = "USB Root Hub";
+					break;
+				case USB_HUB_PROTO_SINGLE_TT:
+					dev->product = "USB Single TT Hub";
+					break;
+				default:
+					dev->product = "USB Hub";
+					break;
+			}
+			break;
+		case USB_CLASS_MASS_STORAGE:
+			dev->product = "USB Mass Storage";
+			break;
+		default:
+			dev->product = "Unknown USB Device";
+			break;
+	}
+}
+
+
+static void usb_guessManufacturerString(usb_dev_t *dev)
+{
+	dev->manufacturer = "Generic";
+}
+
+
+static void usb_setSerialNumberString(usb_dev_t *dev)
+{
+	dev->serialNumber = "Unknown";
+}
+
+
 static int usb_getAllStringDescs(usb_dev_t *dev)
 {
 	usb_string_desc_t desc = { 0 };
 	int i;
 
+	/* Get an array of language ids */
+	/* String descriptors are optional. If a device omits all string descriptors,
+	 * it must not return this array, so the following call is allowed to fail in
+	 * that case */
 	if (usb_getDescriptor(dev, USB_DESC_STRING, 0, (char *)&desc, sizeof(desc)) < 0) {
-		USB_LOG("usb: Fail to get configuration descriptor\n");
-		return -1;
+		usb_guessManufacturerString(dev);
+		usb_guessProductString(dev);
+		usb_setSerialNumberString(dev);
+		return -ENOTSUP;
 	}
 
 	if (desc.bLength < 4)
@@ -392,16 +439,25 @@ static int usb_getAllStringDescs(usb_dev_t *dev)
 		if (usb_getStringDesc(dev, &dev->manufacturer, dev->desc.iManufacturer) != 0)
 			return -ENOMEM;
 	}
+	else {
+		usb_guessManufacturerString(dev);
+	}
 
 	if (dev->desc.iProduct != 0) {
 		if (usb_getStringDesc(dev, &dev->product, dev->desc.iProduct) != 0)
 			return -ENOMEM;
 	}
+	else {
+		usb_guessProductString(dev);
+	}
 
 	if (dev->desc.iSerialNumber != 0) {
 		if (usb_getStringDesc(dev, &dev->serialNumber, dev->desc.iSerialNumber) != 0)
 			return -ENOMEM;
 	}
+	else {
+		usb_setSerialNumberString(dev);
+	}
 
 	for (i = 0; i < dev->nifs; i++) {
 		if (dev->ifs[i].desc->iInterface == 0)
@@ -453,7 +509,8 @@ int usb_devEnumerate(usb_dev_t *dev)
 		return -1;
 	}
 
-	if (usb_getAllStringDescs(dev) < 0) {
+	ret = usb_getAllStringDescs(dev);
+	if (ret < 0 && ret != -ENOTSUP) {
 		USB_LOG("usb: Fail to get string descriptors\n");
 		return -1;
 	}
@@ -462,7 +519,7 @@ int usb_devEnumerate(usb_dev_t *dev)
 		usb_devSetChild(dev->hub, dev->port, dev);
 
 	USB_LOG("usb: New device addr: %d locationID: %08x %s, %s\n", dev->address, dev->locationID,
-		dev->manufacturer, dev->product);
+			dev->manufacturer, dev->product);
 
 	if (dev->desc.bDeviceClass == USB_CLASS_HUB) {
 		if (hub_conf(dev) != 0)