ALSA: usb-audio: Use strings in struct usb_dev for manufacturer & co

The USB core already prepares the strings for manufacturer, product
and serial number, and we don't have to extract the string at each
time.  Replace the manual usb_string() calls with the corresponding
pointers in struct usb_dev as a code cleanup.

Link: https://patch.msgid.link/20260305130426.975604-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Author: tiwai

sound/usb/card.c

@@ -631,9 +631,9 @@ static void usb_audio_make_shortname(struct usb_device *dev,
 	}
 
 	/* retrieve the device string as shortname */
-	if (!dev->descriptor.iProduct ||
-	    usb_string(dev, dev->descriptor.iProduct,
-		       card->shortname, sizeof(card->shortname)) <= 0) {
+	if (dev->product && *dev->product) {
+		strscpy(card->shortname, dev->product);
+	} else {
 		/* no name available from anywhere, so use ID */
 		scnprintf(card->shortname, sizeof(card->shortname),
 			  "USB Device %#04x:%#04x",
@@ -668,15 +668,11 @@ static void usb_audio_make_longname(struct usb_device *dev,
 	else if (quirk && quirk->vendor_name)
 		s = quirk->vendor_name;
 	*card->longname = 0;
-	if (s && *s) {
-		strscpy(card->longname, s, sizeof(card->longname));
-	} else {
-		/* retrieve the vendor and device strings as longname */
-		if (dev->descriptor.iManufacturer)
-			usb_string(dev, dev->descriptor.iManufacturer,
-				   card->longname, sizeof(card->longname));
-		/* we don't really care if there isn't any vendor string */
-	}
+	if (s && *s)
+		strscpy(card->longname, s);
+	else if (dev->manufacturer && *dev->manufacturer)
+		strscpy(card->longname, dev->manufacturer);
+
 	if (*card->longname) {
 		strim(card->longname);
 		if (*card->longname)

sound/usb/midi2.c

@@ -1057,10 +1057,8 @@ static void set_fallback_rawmidi_names(struct snd_usb_midi2_interface *umidi)
 			strscpy(ump->core.name, ump->info.name,
 				sizeof(ump->core.name));
 		/* use serial number string as unique UMP product id */
-		if (!*ump->info.product_id && dev->descriptor.iSerialNumber)
-			usb_string(dev, dev->descriptor.iSerialNumber,
-				   ump->info.product_id,
-				   sizeof(ump->info.product_id));
+		if (!*ump->info.product_id && dev->serial && *dev->serial)
+			strscpy(ump->info.product_id, dev->serial);
 	}
 }