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				synced 2025-11-03 18:20:25 +02:00 
			
		
		
		
	No code altered at this point, simply preparing for upcoming refactorizations. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
		
			
				
	
	
		
			452 lines
		
	
	
	
		
			13 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			452 lines
		
	
	
	
		
			13 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *   This program is free software; you can redistribute it and/or modify
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 *   it under the terms of the GNU General Public License as published by
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 *   the Free Software Foundation; either version 2 of the License, or
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 *   (at your option) any later version.
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 *
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 *   This program is distributed in the hope that it will be useful,
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 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 *   GNU General Public License for more details.
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 *
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 *   You should have received a copy of the GNU General Public License
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 *   along with this program; if not, write to the Free Software
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 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
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 */
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/usb.h>
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#include <linux/usb/audio.h>
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#include <linux/usb/audio-v2.h>
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#include <sound/core.h>
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#include <sound/pcm.h>
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#include "usbaudio.h"
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#include "card.h"
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#include "proc.h"
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#include "quirks.h"
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#include "endpoint.h"
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#include "pcm.h"
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#include "helper.h"
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#include "format.h"
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#include "clock.h"
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#include "stream.h"
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/*
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 * free a substream
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 */
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static void free_substream(struct snd_usb_substream *subs)
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{
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	struct list_head *p, *n;
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	if (!subs->num_formats)
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		return; /* not initialized */
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	list_for_each_safe(p, n, &subs->fmt_list) {
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		struct audioformat *fp = list_entry(p, struct audioformat, list);
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		kfree(fp->rate_table);
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		kfree(fp);
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	}
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	kfree(subs->rate_list.list);
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}
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/*
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 * free a usb stream instance
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 */
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static void snd_usb_audio_stream_free(struct snd_usb_stream *stream)
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{
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	free_substream(&stream->substream[0]);
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	free_substream(&stream->substream[1]);
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	list_del(&stream->list);
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	kfree(stream);
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}
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static void snd_usb_audio_pcm_free(struct snd_pcm *pcm)
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{
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	struct snd_usb_stream *stream = pcm->private_data;
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	if (stream) {
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		stream->pcm = NULL;
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		snd_usb_audio_stream_free(stream);
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	}
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}
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/*
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 * add this endpoint to the chip instance.
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 * if a stream with the same endpoint already exists, append to it.
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 * if not, create a new pcm stream.
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 */
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int snd_usb_add_audio_stream(struct snd_usb_audio *chip,
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			     int stream,
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			     struct audioformat *fp)
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{
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	struct list_head *p;
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	struct snd_usb_stream *as;
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	struct snd_usb_substream *subs;
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	struct snd_pcm *pcm;
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	int err;
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	list_for_each(p, &chip->pcm_list) {
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		as = list_entry(p, struct snd_usb_stream, list);
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		if (as->fmt_type != fp->fmt_type)
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			continue;
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		subs = &as->substream[stream];
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		if (!subs->endpoint)
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			continue;
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		if (subs->endpoint == fp->endpoint) {
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			list_add_tail(&fp->list, &subs->fmt_list);
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			subs->num_formats++;
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			subs->formats |= fp->formats;
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			return 0;
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		}
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	}
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	/* look for an empty stream */
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	list_for_each(p, &chip->pcm_list) {
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		as = list_entry(p, struct snd_usb_stream, list);
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		if (as->fmt_type != fp->fmt_type)
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			continue;
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		subs = &as->substream[stream];
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		if (subs->endpoint)
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			continue;
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		err = snd_pcm_new_stream(as->pcm, stream, 1);
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		if (err < 0)
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			return err;
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		snd_usb_init_substream(as, stream, fp);
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		return 0;
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	}
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	/* create a new pcm */
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	as = kzalloc(sizeof(*as), GFP_KERNEL);
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	if (!as)
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		return -ENOMEM;
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	as->pcm_index = chip->pcm_devs;
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	as->chip = chip;
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	as->fmt_type = fp->fmt_type;
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	err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
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			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
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			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
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			  &pcm);
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	if (err < 0) {
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		kfree(as);
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		return err;
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	}
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	as->pcm = pcm;
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	pcm->private_data = as;
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	pcm->private_free = snd_usb_audio_pcm_free;
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	pcm->info_flags = 0;
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	if (chip->pcm_devs > 0)
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		sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
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	else
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		strcpy(pcm->name, "USB Audio");
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	snd_usb_init_substream(as, stream, fp);
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	list_add(&as->list, &chip->pcm_list);
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	chip->pcm_devs++;
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	snd_usb_proc_pcm_format_add(as);
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	return 0;
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}
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static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
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					 struct usb_host_interface *alts,
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					 int protocol, int iface_no)
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{
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	/* parsed with a v1 header here. that's ok as we only look at the
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	 * header first which is the same for both versions */
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	struct uac_iso_endpoint_descriptor *csep;
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	struct usb_interface_descriptor *altsd = get_iface_desc(alts);
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	int attributes = 0;
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	csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
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	/* Creamware Noah has this descriptor after the 2nd endpoint */
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	if (!csep && altsd->bNumEndpoints >= 2)
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		csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
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	if (!csep || csep->bLength < 7 ||
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	    csep->bDescriptorSubtype != UAC_EP_GENERAL) {
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		snd_printk(KERN_WARNING "%d:%u:%d : no or invalid"
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			   " class specific endpoint descriptor\n",
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			   chip->dev->devnum, iface_no,
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			   altsd->bAlternateSetting);
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		return 0;
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	}
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	if (protocol == UAC_VERSION_1) {
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		attributes = csep->bmAttributes;
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	} else {
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		struct uac2_iso_endpoint_descriptor *csep2 =
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			(struct uac2_iso_endpoint_descriptor *) csep;
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		attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;
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		/* emulate the endpoint attributes of a v1 device */
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		if (csep2->bmControls & UAC2_CONTROL_PITCH)
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			attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
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	}
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	return attributes;
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}
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static struct uac2_input_terminal_descriptor *
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	snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
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					       int terminal_id)
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{
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	struct uac2_input_terminal_descriptor *term = NULL;
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	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
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					       ctrl_iface->extralen,
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					       term, UAC_INPUT_TERMINAL))) {
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		if (term->bTerminalID == terminal_id)
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			return term;
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	}
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	return NULL;
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}
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static struct uac2_output_terminal_descriptor *
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	snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
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						int terminal_id)
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{
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	struct uac2_output_terminal_descriptor *term = NULL;
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	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
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					       ctrl_iface->extralen,
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					       term, UAC_OUTPUT_TERMINAL))) {
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		if (term->bTerminalID == terminal_id)
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			return term;
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	}
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	return NULL;
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}
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int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
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{
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	struct usb_device *dev;
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	struct usb_interface *iface;
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	struct usb_host_interface *alts;
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	struct usb_interface_descriptor *altsd;
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	int i, altno, err, stream;
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	int format = 0, num_channels = 0;
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	struct audioformat *fp = NULL;
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	int num, protocol, clock = 0;
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	struct uac_format_type_i_continuous_descriptor *fmt;
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	dev = chip->dev;
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	/* parse the interface's altsettings */
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	iface = usb_ifnum_to_if(dev, iface_no);
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	num = iface->num_altsetting;
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	/*
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	 * Dallas DS4201 workaround: It presents 5 altsettings, but the last
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	 * one misses syncpipe, and does not produce any sound.
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	 */
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	if (chip->usb_id == USB_ID(0x04fa, 0x4201))
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		num = 4;
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	for (i = 0; i < num; i++) {
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		alts = &iface->altsetting[i];
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		altsd = get_iface_desc(alts);
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		protocol = altsd->bInterfaceProtocol;
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		/* skip invalid one */
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		if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
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		     altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
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		    (altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING &&
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		     altsd->bInterfaceSubClass != USB_SUBCLASS_VENDOR_SPEC) ||
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		    altsd->bNumEndpoints < 1 ||
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		    le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) == 0)
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			continue;
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		/* must be isochronous */
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		if ((get_endpoint(alts, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) !=
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		    USB_ENDPOINT_XFER_ISOC)
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			continue;
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		/* check direction */
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		stream = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN) ?
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			SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
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		altno = altsd->bAlternateSetting;
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		if (snd_usb_apply_interface_quirk(chip, iface_no, altno))
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			continue;
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		/* get audio formats */
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		switch (protocol) {
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		default:
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			snd_printdd(KERN_WARNING "%d:%u:%d: unknown interface protocol %#02x, assuming v1\n",
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				    dev->devnum, iface_no, altno, protocol);
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			protocol = UAC_VERSION_1;
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			/* fall through */
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		case UAC_VERSION_1: {
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			struct uac1_as_header_descriptor *as =
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				snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
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			if (!as) {
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				snd_printk(KERN_ERR "%d:%u:%d : UAC_AS_GENERAL descriptor not found\n",
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					   dev->devnum, iface_no, altno);
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				continue;
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			}
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			if (as->bLength < sizeof(*as)) {
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				snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_AS_GENERAL desc\n",
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					   dev->devnum, iface_no, altno);
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				continue;
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			}
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			format = le16_to_cpu(as->wFormatTag); /* remember the format value */
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			break;
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		}
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		case UAC_VERSION_2: {
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			struct uac2_input_terminal_descriptor *input_term;
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			struct uac2_output_terminal_descriptor *output_term;
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			struct uac2_as_header_descriptor *as =
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				snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
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			if (!as) {
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				snd_printk(KERN_ERR "%d:%u:%d : UAC_AS_GENERAL descriptor not found\n",
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					   dev->devnum, iface_no, altno);
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				continue;
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			}
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			if (as->bLength < sizeof(*as)) {
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				snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_AS_GENERAL desc\n",
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					   dev->devnum, iface_no, altno);
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				continue;
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			}
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			num_channels = as->bNrChannels;
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			format = le32_to_cpu(as->bmFormats);
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			/* lookup the terminal associated to this interface
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			 * to extract the clock */
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			input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
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									    as->bTerminalLink);
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			if (input_term) {
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				clock = input_term->bCSourceID;
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				break;
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			}
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			output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
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									      as->bTerminalLink);
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			if (output_term) {
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				clock = output_term->bCSourceID;
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				break;
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			}
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			snd_printk(KERN_ERR "%d:%u:%d : bogus bTerminalLink %d\n",
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				   dev->devnum, iface_no, altno, as->bTerminalLink);
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			continue;
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		}
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		}
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		/* get format type */
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		fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_FORMAT_TYPE);
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		if (!fmt) {
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			snd_printk(KERN_ERR "%d:%u:%d : no UAC_FORMAT_TYPE desc\n",
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				   dev->devnum, iface_no, altno);
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			continue;
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		}
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		if (((protocol == UAC_VERSION_1) && (fmt->bLength < 8)) ||
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		    ((protocol == UAC_VERSION_2) && (fmt->bLength < 6))) {
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			snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_FORMAT_TYPE desc\n",
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				   dev->devnum, iface_no, altno);
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			continue;
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		}
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		/*
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		 * Blue Microphones workaround: The last altsetting is identical
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		 * with the previous one, except for a larger packet size, but
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		 * is actually a mislabeled two-channel setting; ignore it.
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		 */
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		if (fmt->bNrChannels == 1 &&
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		    fmt->bSubframeSize == 2 &&
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		    altno == 2 && num == 3 &&
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		    fp && fp->altsetting == 1 && fp->channels == 1 &&
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		    fp->formats == SNDRV_PCM_FMTBIT_S16_LE &&
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		    protocol == UAC_VERSION_1 &&
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		    le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) ==
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							fp->maxpacksize * 2)
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			continue;
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 | 
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		fp = kzalloc(sizeof(*fp), GFP_KERNEL);
 | 
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		if (! fp) {
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			snd_printk(KERN_ERR "cannot malloc\n");
 | 
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			return -ENOMEM;
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		}
 | 
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 | 
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		fp->iface = iface_no;
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		fp->altsetting = altno;
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		fp->altset_idx = i;
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		fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
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		fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
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		fp->datainterval = snd_usb_parse_datainterval(chip, alts);
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		fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
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		/* num_channels is only set for v2 interfaces */
 | 
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		fp->channels = num_channels;
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		if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
 | 
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			fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
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					* (fp->maxpacksize & 0x7ff);
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		fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
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		fp->clock = clock;
 | 
						|
 | 
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		/* some quirks for attributes here */
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						|
 | 
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		switch (chip->usb_id) {
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		case USB_ID(0x0a92, 0x0053): /* AudioTrak Optoplay */
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			/* Optoplay sets the sample rate attribute although
 | 
						|
			 * it seems not supporting it in fact.
 | 
						|
			 */
 | 
						|
			fp->attributes &= ~UAC_EP_CS_ATTR_SAMPLE_RATE;
 | 
						|
			break;
 | 
						|
		case USB_ID(0x041e, 0x3020): /* Creative SB Audigy 2 NX */
 | 
						|
		case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
 | 
						|
			/* doesn't set the sample rate attribute, but supports it */
 | 
						|
			fp->attributes |= UAC_EP_CS_ATTR_SAMPLE_RATE;
 | 
						|
			break;
 | 
						|
		case USB_ID(0x0763, 0x2001):  /* M-Audio Quattro USB */
 | 
						|
		case USB_ID(0x0763, 0x2012):  /* M-Audio Fast Track Pro USB */
 | 
						|
		case USB_ID(0x047f, 0x0ca1): /* plantronics headset */
 | 
						|
		case USB_ID(0x077d, 0x07af): /* Griffin iMic (note that there is
 | 
						|
						an older model 77d:223) */
 | 
						|
		/*
 | 
						|
		 * plantronics headset and Griffin iMic have set adaptive-in
 | 
						|
		 * although it's really not...
 | 
						|
		 */
 | 
						|
			fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
 | 
						|
			if (stream == SNDRV_PCM_STREAM_PLAYBACK)
 | 
						|
				fp->ep_attr |= USB_ENDPOINT_SYNC_ADAPTIVE;
 | 
						|
			else
 | 
						|
				fp->ep_attr |= USB_ENDPOINT_SYNC_SYNC;
 | 
						|
			break;
 | 
						|
		}
 | 
						|
 | 
						|
		/* ok, let's parse further... */
 | 
						|
		if (snd_usb_parse_audio_format(chip, fp, format, fmt, stream, alts) < 0) {
 | 
						|
			kfree(fp->rate_table);
 | 
						|
			kfree(fp);
 | 
						|
			fp = NULL;
 | 
						|
			continue;
 | 
						|
		}
 | 
						|
 | 
						|
		snd_printdd(KERN_INFO "%d:%u:%d: add audio endpoint %#x\n", dev->devnum, iface_no, altno, fp->endpoint);
 | 
						|
		err = snd_usb_add_audio_stream(chip, stream, fp);
 | 
						|
		if (err < 0) {
 | 
						|
			kfree(fp->rate_table);
 | 
						|
			kfree(fp);
 | 
						|
			return err;
 | 
						|
		}
 | 
						|
		/* try to set the interface... */
 | 
						|
		usb_set_interface(chip->dev, iface_no, altno);
 | 
						|
		snd_usb_init_pitch(chip, iface_no, alts, fp);
 | 
						|
		snd_usb_init_sample_rate(chip, iface_no, alts, fp, fp->rate_max);
 | 
						|
	}
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 |