ALSA: usb-audio: Annotate the endpoint index in audioformat

There are devices that have multiple endpoints sharing the same
iface/altset not only for sync but also for the actual streams, and
the audioformat for such an endpoint needs to be handled with the
proper endpoint index; otherwise it confuses the endpoint management.

This patch extends the audioformat to annotate the endpoint index, and
put the proper ep_idx=1 to Pioneer device quirk entries accordingly.

Fixes: bf6313a0ff76 ("ALSA: usb-audio: Refactor endpoint management")
Link: https://lore.kernel.org/r/20210108075219.21463-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index b70e2eb..89e1726 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -194,7 +194,7 @@ static int create_fixed_stream_quirk(struct snd_usb_audio *chip,
 	}
 	alts = &iface->altsetting[fp->altset_idx];
 	altsd = get_iface_desc(alts);
-	if (altsd->bNumEndpoints < 1) {
+	if (altsd->bNumEndpoints <= fp->ep_idx) {
 		err = -EINVAL;
 		goto error;
 	}
@@ -204,7 +204,7 @@ static int create_fixed_stream_quirk(struct snd_usb_audio *chip,
 	if (fp->datainterval == 0)
 		fp->datainterval = snd_usb_parse_datainterval(chip, alts);
 	if (fp->maxpacksize == 0)
-		fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
+		fp->maxpacksize = le16_to_cpu(get_endpoint(alts, fp->ep_idx)->wMaxPacketSize);
 	if (!fp->fmt_type)
 		fp->fmt_type = UAC_FORMAT_TYPE_I;