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  1/*
  2 *   This program is free software; you can redistribute it and/or modify
  3 *   it under the terms of the GNU General Public License as published by
  4 *   the Free Software Foundation; either version 2 of the License, or
  5 *   (at your option) any later version.
  6 *
  7 *   This program is distributed in the hope that it will be useful,
  8 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  9 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 10 *   GNU General Public License for more details.
 11 *
 12 *   You should have received a copy of the GNU General Public License
 13 *   along with this program; if not, write to the Free Software
 14 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 15 */
 16
 17
 18#include <linux/init.h>
 19#include <linux/slab.h>
 20#include <linux/usb.h>
 21#include <linux/usb/audio.h>
 22#include <linux/usb/audio-v2.h>
 23
 24#include <sound/core.h>
 25#include <sound/pcm.h>
 26#include <sound/control.h>
 27#include <sound/tlv.h>
 28
 29#include "usbaudio.h"
 30#include "card.h"
 31#include "proc.h"
 32#include "quirks.h"
 33#include "endpoint.h"
 34#include "pcm.h"
 35#include "helper.h"
 36#include "format.h"
 37#include "clock.h"
 38#include "stream.h"
 39
 40/*
 41 * free a substream
 42 */
 43static void free_substream(struct snd_usb_substream *subs)
 44{
 45	struct audioformat *fp, *n;
 46
 47	if (!subs->num_formats)
 48		return; /* not initialized */
 49	list_for_each_entry_safe(fp, n, &subs->fmt_list, list) {
 50		kfree(fp->rate_table);
 51		kfree(fp->chmap);
 52		kfree(fp);
 53	}
 54	kfree(subs->rate_list.list);
 55}
 56
 57
 58/*
 59 * free a usb stream instance
 60 */
 61static void snd_usb_audio_stream_free(struct snd_usb_stream *stream)
 62{
 63	free_substream(&stream->substream[0]);
 64	free_substream(&stream->substream[1]);
 65	list_del(&stream->list);
 66	kfree(stream);
 67}
 68
 69static void snd_usb_audio_pcm_free(struct snd_pcm *pcm)
 70{
 71	struct snd_usb_stream *stream = pcm->private_data;
 72	if (stream) {
 73		stream->pcm = NULL;
 74		snd_usb_audio_stream_free(stream);
 75	}
 76}
 77
 78/*
 79 * initialize the substream instance.
 80 */
 81
 82static void snd_usb_init_substream(struct snd_usb_stream *as,
 83				   int stream,
 84				   struct audioformat *fp)
 85{
 86	struct snd_usb_substream *subs = &as->substream[stream];
 87
 88	INIT_LIST_HEAD(&subs->fmt_list);
 89	spin_lock_init(&subs->lock);
 90
 91	subs->stream = as;
 92	subs->direction = stream;
 93	subs->dev = as->chip->dev;
 94	subs->txfr_quirk = as->chip->txfr_quirk;
 95	subs->speed = snd_usb_get_speed(subs->dev);
 96	subs->pkt_offset_adj = 0;
 97
 98	snd_usb_set_pcm_ops(as->pcm, stream);
 99
100	list_add_tail(&fp->list, &subs->fmt_list);
101	subs->formats |= fp->formats;
102	subs->num_formats++;
103	subs->fmt_type = fp->fmt_type;
104	subs->ep_num = fp->endpoint;
105	if (fp->channels > subs->channels_max)
106		subs->channels_max = fp->channels;
107}
108
109/* kctl callbacks for usb-audio channel maps */
110static int usb_chmap_ctl_info(struct snd_kcontrol *kcontrol,
111			      struct snd_ctl_elem_info *uinfo)
112{
113	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
114	struct snd_usb_substream *subs = info->private_data;
115
116	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
117	uinfo->count = subs->channels_max;
118	uinfo->value.integer.min = 0;
119	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
120	return 0;
121}
122
123/* check whether a duplicated entry exists in the audiofmt list */
124static bool have_dup_chmap(struct snd_usb_substream *subs,
125			   struct audioformat *fp)
126{
127	struct list_head *p;
128
129	for (p = fp->list.prev; p != &subs->fmt_list; p = p->prev) {
130		struct audioformat *prev;
131		prev = list_entry(p, struct audioformat, list);
132		if (prev->chmap &&
133		    !memcmp(prev->chmap, fp->chmap, sizeof(*fp->chmap)))
134			return true;
135	}
136	return false;
137}
138
139static int usb_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
140			     unsigned int size, unsigned int __user *tlv)
141{
142	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
143	struct snd_usb_substream *subs = info->private_data;
144	struct audioformat *fp;
145	unsigned int __user *dst;
146	int count = 0;
147
148	if (size < 8)
149		return -ENOMEM;
150	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
151		return -EFAULT;
152	size -= 8;
153	dst = tlv + 2;
154	list_for_each_entry(fp, &subs->fmt_list, list) {
155		int i, ch_bytes;
156
157		if (!fp->chmap)
158			continue;
159		if (have_dup_chmap(subs, fp))
160			continue;
161		/* copy the entry */
162		ch_bytes = fp->chmap->channels * 4;
163		if (size < 8 + ch_bytes)
164			return -ENOMEM;
165		if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
166		    put_user(ch_bytes, dst + 1))
167			return -EFAULT;
168		dst += 2;
169		for (i = 0; i < fp->chmap->channels; i++, dst++) {
170			if (put_user(fp->chmap->map[i], dst))
171				return -EFAULT;
172		}
173
174		count += 8 + ch_bytes;
175		size -= 8 + ch_bytes;
176	}
177	if (put_user(count, tlv + 1))
178		return -EFAULT;
179	return 0;
180}
181
182static int usb_chmap_ctl_get(struct snd_kcontrol *kcontrol,
183			     struct snd_ctl_elem_value *ucontrol)
184{
185	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
186	struct snd_usb_substream *subs = info->private_data;
187	struct snd_pcm_chmap_elem *chmap = NULL;
188	int i;
189
190	memset(ucontrol->value.integer.value, 0,
191	       sizeof(ucontrol->value.integer.value));
192	if (subs->cur_audiofmt)
193		chmap = subs->cur_audiofmt->chmap;
194	if (chmap) {
195		for (i = 0; i < chmap->channels; i++)
196			ucontrol->value.integer.value[i] = chmap->map[i];
197	}
198	return 0;
199}
200
201/* create a chmap kctl assigned to the given USB substream */
202static int add_chmap(struct snd_pcm *pcm, int stream,
203		     struct snd_usb_substream *subs)
204{
205	struct audioformat *fp;
206	struct snd_pcm_chmap *chmap;
207	struct snd_kcontrol *kctl;
208	int err;
209
210	list_for_each_entry(fp, &subs->fmt_list, list)
211		if (fp->chmap)
212			goto ok;
213	/* no chmap is found */
214	return 0;
215
216 ok:
217	err = snd_pcm_add_chmap_ctls(pcm, stream, NULL, 0, 0, &chmap);
218	if (err < 0)
219		return err;
220
221	/* override handlers */
222	chmap->private_data = subs;
223	kctl = chmap->kctl;
224	kctl->info = usb_chmap_ctl_info;
225	kctl->get = usb_chmap_ctl_get;
226	kctl->tlv.c = usb_chmap_ctl_tlv;
227
228	return 0;
229}
230
231/* convert from USB ChannelConfig bits to ALSA chmap element */
232static struct snd_pcm_chmap_elem *convert_chmap(int channels, unsigned int bits,
233						int protocol)
234{
235	static unsigned int uac1_maps[] = {
236		SNDRV_CHMAP_FL,		/* left front */
237		SNDRV_CHMAP_FR,		/* right front */
238		SNDRV_CHMAP_FC,		/* center front */
239		SNDRV_CHMAP_LFE,	/* LFE */
240		SNDRV_CHMAP_SL,		/* left surround */
241		SNDRV_CHMAP_SR,		/* right surround */
242		SNDRV_CHMAP_FLC,	/* left of center */
243		SNDRV_CHMAP_FRC,	/* right of center */
244		SNDRV_CHMAP_RC,		/* surround */
245		SNDRV_CHMAP_SL,		/* side left */
246		SNDRV_CHMAP_SR,		/* side right */
247		SNDRV_CHMAP_TC,		/* top */
248		0 /* terminator */
249	};
250	static unsigned int uac2_maps[] = {
251		SNDRV_CHMAP_FL,		/* front left */
252		SNDRV_CHMAP_FR,		/* front right */
253		SNDRV_CHMAP_FC,		/* front center */
254		SNDRV_CHMAP_LFE,	/* LFE */
255		SNDRV_CHMAP_RL,		/* back left */
256		SNDRV_CHMAP_RR,		/* back right */
257		SNDRV_CHMAP_FLC,	/* front left of center */
258		SNDRV_CHMAP_FRC,	/* front right of center */
259		SNDRV_CHMAP_RC,		/* back center */
260		SNDRV_CHMAP_SL,		/* side left */
261		SNDRV_CHMAP_SR,		/* side right */
262		SNDRV_CHMAP_TC,		/* top center */
263		SNDRV_CHMAP_TFL,	/* top front left */
264		SNDRV_CHMAP_TFC,	/* top front center */
265		SNDRV_CHMAP_TFR,	/* top front right */
266		SNDRV_CHMAP_TRL,	/* top back left */
267		SNDRV_CHMAP_TRC,	/* top back center */
268		SNDRV_CHMAP_TRR,	/* top back right */
269		SNDRV_CHMAP_TFLC,	/* top front left of center */
270		SNDRV_CHMAP_TFRC,	/* top front right of center */
271		SNDRV_CHMAP_LLFE,	/* left LFE */
272		SNDRV_CHMAP_RLFE,	/* right LFE */
273		SNDRV_CHMAP_TSL,	/* top side left */
274		SNDRV_CHMAP_TSR,	/* top side right */
275		SNDRV_CHMAP_BC,		/* bottom center */
276		SNDRV_CHMAP_RLC,	/* back left of center */
277		SNDRV_CHMAP_RRC,	/* back right of center */
278		0 /* terminator */
279	};
280	struct snd_pcm_chmap_elem *chmap;
281	const unsigned int *maps;
282	int c;
283
284	if (channels > ARRAY_SIZE(chmap->map))
285		return NULL;
286
287	chmap = kzalloc(sizeof(*chmap), GFP_KERNEL);
288	if (!chmap)
289		return NULL;
290
291	maps = protocol == UAC_VERSION_2 ? uac2_maps : uac1_maps;
292	chmap->channels = channels;
293	c = 0;
294
295	if (bits) {
296		for (; bits && *maps; maps++, bits >>= 1)
297			if (bits & 1)
298				chmap->map[c++] = *maps;
299	} else {
300		/* If we're missing wChannelConfig, then guess something
301		    to make sure the channel map is not skipped entirely */
302		if (channels == 1)
303			chmap->map[c++] = SNDRV_CHMAP_MONO;
304		else
305			for (; c < channels && *maps; maps++)
306				chmap->map[c++] = *maps;
307	}
308
309	for (; c < channels; c++)
310		chmap->map[c] = SNDRV_CHMAP_UNKNOWN;
311
312	return chmap;
313}
314
315/*
316 * add this endpoint to the chip instance.
317 * if a stream with the same endpoint already exists, append to it.
318 * if not, create a new pcm stream.
319 */
320int snd_usb_add_audio_stream(struct snd_usb_audio *chip,
321			     int stream,
322			     struct audioformat *fp)
323{
324	struct snd_usb_stream *as;
325	struct snd_usb_substream *subs;
326	struct snd_pcm *pcm;
327	int err;
328
329	list_for_each_entry(as, &chip->pcm_list, list) {
330		if (as->fmt_type != fp->fmt_type)
331			continue;
332		subs = &as->substream[stream];
333		if (subs->ep_num == fp->endpoint) {
334			list_add_tail(&fp->list, &subs->fmt_list);
335			subs->num_formats++;
336			subs->formats |= fp->formats;
337			return 0;
338		}
339	}
340	/* look for an empty stream */
341	list_for_each_entry(as, &chip->pcm_list, list) {
342		if (as->fmt_type != fp->fmt_type)
343			continue;
344		subs = &as->substream[stream];
345		if (subs->ep_num)
346			continue;
347		err = snd_pcm_new_stream(as->pcm, stream, 1);
348		if (err < 0)
349			return err;
350		snd_usb_init_substream(as, stream, fp);
351		return add_chmap(as->pcm, stream, subs);
352	}
353
354	/* create a new pcm */
355	as = kzalloc(sizeof(*as), GFP_KERNEL);
356	if (!as)
357		return -ENOMEM;
358	as->pcm_index = chip->pcm_devs;
359	as->chip = chip;
360	as->fmt_type = fp->fmt_type;
361	err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
362			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
363			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
364			  &pcm);
365	if (err < 0) {
366		kfree(as);
367		return err;
368	}
369	as->pcm = pcm;
370	pcm->private_data = as;
371	pcm->private_free = snd_usb_audio_pcm_free;
372	pcm->info_flags = 0;
373	if (chip->pcm_devs > 0)
374		sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
375	else
376		strcpy(pcm->name, "USB Audio");
377
378	snd_usb_init_substream(as, stream, fp);
379
380	list_add(&as->list, &chip->pcm_list);
381	chip->pcm_devs++;
382
383	snd_usb_proc_pcm_format_add(as);
384
385	return add_chmap(pcm, stream, &as->substream[stream]);
386}
387
388static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
389					 struct usb_host_interface *alts,
390					 int protocol, int iface_no)
391{
392	/* parsed with a v1 header here. that's ok as we only look at the
393	 * header first which is the same for both versions */
394	struct uac_iso_endpoint_descriptor *csep;
395	struct usb_interface_descriptor *altsd = get_iface_desc(alts);
396	int attributes = 0;
397
398	csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
399
400	/* Creamware Noah has this descriptor after the 2nd endpoint */
401	if (!csep && altsd->bNumEndpoints >= 2)
402		csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
403
404	/*
405	 * If we can't locate the USB_DT_CS_ENDPOINT descriptor in the extra
406	 * bytes after the first endpoint, go search the entire interface.
407	 * Some devices have it directly *before* the standard endpoint.
408	 */
409	if (!csep)
410		csep = snd_usb_find_desc(alts->extra, alts->extralen, NULL, USB_DT_CS_ENDPOINT);
411
412	if (!csep || csep->bLength < 7 ||
413	    csep->bDescriptorSubtype != UAC_EP_GENERAL) {
414		usb_audio_warn(chip,
415			       "%u:%d : no or invalid class specific endpoint descriptor\n",
416			       iface_no, altsd->bAlternateSetting);
417		return 0;
418	}
419
420	if (protocol == UAC_VERSION_1) {
421		attributes = csep->bmAttributes;
422	} else {
423		struct uac2_iso_endpoint_descriptor *csep2 =
424			(struct uac2_iso_endpoint_descriptor *) csep;
425
426		attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;
427
428		/* emulate the endpoint attributes of a v1 device */
429		if (csep2->bmControls & UAC2_CONTROL_PITCH)
430			attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
431	}
432
433	return attributes;
434}
435
436/* find an input terminal descriptor (either UAC1 or UAC2) with the given
437 * terminal id
438 */
439static void *
440snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
441					       int terminal_id)
442{
443	struct uac2_input_terminal_descriptor *term = NULL;
444
445	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
446					       ctrl_iface->extralen,
447					       term, UAC_INPUT_TERMINAL))) {
448		if (term->bTerminalID == terminal_id)
449			return term;
450	}
451
452	return NULL;
453}
454
455static struct uac2_output_terminal_descriptor *
456	snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
457						int terminal_id)
458{
459	struct uac2_output_terminal_descriptor *term = NULL;
460
461	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
462					       ctrl_iface->extralen,
463					       term, UAC_OUTPUT_TERMINAL))) {
464		if (term->bTerminalID == terminal_id)
465			return term;
466	}
467
468	return NULL;
469}
470
471int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
472{
473	struct usb_device *dev;
474	struct usb_interface *iface;
475	struct usb_host_interface *alts;
476	struct usb_interface_descriptor *altsd;
477	int i, altno, err, stream;
478	unsigned int format = 0, num_channels = 0;
479	struct audioformat *fp = NULL;
480	int num, protocol, clock = 0;
481	struct uac_format_type_i_continuous_descriptor *fmt;
482	unsigned int chconfig;
483
484	dev = chip->dev;
485
486	/* parse the interface's altsettings */
487	iface = usb_ifnum_to_if(dev, iface_no);
488
489	num = iface->num_altsetting;
490
491	/*
492	 * Dallas DS4201 workaround: It presents 5 altsettings, but the last
493	 * one misses syncpipe, and does not produce any sound.
494	 */
495	if (chip->usb_id == USB_ID(0x04fa, 0x4201))
496		num = 4;
497
498	for (i = 0; i < num; i++) {
499		alts = &iface->altsetting[i];
500		altsd = get_iface_desc(alts);
501		protocol = altsd->bInterfaceProtocol;
502		/* skip invalid one */
503		if (((altsd->bInterfaceClass != USB_CLASS_AUDIO ||
504		      (altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING &&
505		       altsd->bInterfaceSubClass != USB_SUBCLASS_VENDOR_SPEC)) &&
506		     altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
507		    altsd->bNumEndpoints < 1 ||
508		    le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) == 0)
509			continue;
510		/* must be isochronous */
511		if ((get_endpoint(alts, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) !=
512		    USB_ENDPOINT_XFER_ISOC)
513			continue;
514		/* check direction */
515		stream = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN) ?
516			SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
517		altno = altsd->bAlternateSetting;
518
519		if (snd_usb_apply_interface_quirk(chip, iface_no, altno))
520			continue;
521
522		/*
523		 * Roland audio streaming interfaces are marked with protocols
524		 * 0/1/2, but are UAC 1 compatible.
525		 */
526		if (USB_ID_VENDOR(chip->usb_id) == 0x0582 &&
527		    altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
528		    protocol <= 2)
529			protocol = UAC_VERSION_1;
530
531		chconfig = 0;
532		/* get audio formats */
533		switch (protocol) {
534		default:
535			dev_dbg(&dev->dev, "%u:%d: unknown interface protocol %#02x, assuming v1\n",
536				iface_no, altno, protocol);
537			protocol = UAC_VERSION_1;
538			/* fall through */
539
540		case UAC_VERSION_1: {
541			struct uac1_as_header_descriptor *as =
542				snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
543			struct uac_input_terminal_descriptor *iterm;
544
545			if (!as) {
546				dev_err(&dev->dev,
547					"%u:%d : UAC_AS_GENERAL descriptor not found\n",
548					iface_no, altno);
549				continue;
550			}
551
552			if (as->bLength < sizeof(*as)) {
553				dev_err(&dev->dev,
554					"%u:%d : invalid UAC_AS_GENERAL desc\n",
555					iface_no, altno);
556				continue;
557			}
558
559			format = le16_to_cpu(as->wFormatTag); /* remember the format value */
560
561			iterm = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
562								       as->bTerminalLink);
563			if (iterm) {
564				num_channels = iterm->bNrChannels;
565				chconfig = le16_to_cpu(iterm->wChannelConfig);
566			}
567
568			break;
569		}
570
571		case UAC_VERSION_2: {
572			struct uac2_input_terminal_descriptor *input_term;
573			struct uac2_output_terminal_descriptor *output_term;
574			struct uac2_as_header_descriptor *as =
575				snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
576
577			if (!as) {
578				dev_err(&dev->dev,
579					"%u:%d : UAC_AS_GENERAL descriptor not found\n",
580					iface_no, altno);
581				continue;
582			}
583
584			if (as->bLength < sizeof(*as)) {
585				dev_err(&dev->dev,
586					"%u:%d : invalid UAC_AS_GENERAL desc\n",
587					iface_no, altno);
588				continue;
589			}
590
591			num_channels = as->bNrChannels;
592			format = le32_to_cpu(as->bmFormats);
593			chconfig = le32_to_cpu(as->bmChannelConfig);
594
595			/* lookup the terminal associated to this interface
596			 * to extract the clock */
597			input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
598									    as->bTerminalLink);
599			if (input_term) {
600				clock = input_term->bCSourceID;
601				if (!chconfig && (num_channels == input_term->bNrChannels))
602					chconfig = le32_to_cpu(input_term->bmChannelConfig);
603				break;
604			}
605
606			output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
607									      as->bTerminalLink);
608			if (output_term) {
609				clock = output_term->bCSourceID;
610				break;
611			}
612
613			dev_err(&dev->dev,
614				"%u:%d : bogus bTerminalLink %d\n",
615				iface_no, altno, as->bTerminalLink);
616			continue;
617		}
618		}
619
620		/* get format type */
621		fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_FORMAT_TYPE);
622		if (!fmt) {
623			dev_err(&dev->dev,
624				"%u:%d : no UAC_FORMAT_TYPE desc\n",
625				iface_no, altno);
626			continue;
627		}
628		if (((protocol == UAC_VERSION_1) && (fmt->bLength < 8)) ||
629		    ((protocol == UAC_VERSION_2) && (fmt->bLength < 6))) {
630			dev_err(&dev->dev,
631				"%u:%d : invalid UAC_FORMAT_TYPE desc\n",
632				iface_no, altno);
633			continue;
634		}
635
636		/*
637		 * Blue Microphones workaround: The last altsetting is identical
638		 * with the previous one, except for a larger packet size, but
639		 * is actually a mislabeled two-channel setting; ignore it.
640		 */
641		if (fmt->bNrChannels == 1 &&
642		    fmt->bSubframeSize == 2 &&
643		    altno == 2 && num == 3 &&
644		    fp && fp->altsetting == 1 && fp->channels == 1 &&
645		    fp->formats == SNDRV_PCM_FMTBIT_S16_LE &&
646		    protocol == UAC_VERSION_1 &&
647		    le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) ==
648							fp->maxpacksize * 2)
649			continue;
650
651		fp = kzalloc(sizeof(*fp), GFP_KERNEL);
652		if (! fp) {
653			dev_err(&dev->dev, "cannot malloc\n");
654			return -ENOMEM;
655		}
656
657		fp->iface = iface_no;
658		fp->altsetting = altno;
659		fp->altset_idx = i;
660		fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
661		fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
662		fp->datainterval = snd_usb_parse_datainterval(chip, alts);
663		fp->protocol = protocol;
664		fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
665		fp->channels = num_channels;
666		if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
667			fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
668					* (fp->maxpacksize & 0x7ff);
669		fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
670		fp->clock = clock;
671
672		/* some quirks for attributes here */
673
674		switch (chip->usb_id) {
675		case USB_ID(0x0a92, 0x0053): /* AudioTrak Optoplay */
676			/* Optoplay sets the sample rate attribute although
677			 * it seems not supporting it in fact.
678			 */
679			fp->attributes &= ~UAC_EP_CS_ATTR_SAMPLE_RATE;
680			break;
681		case USB_ID(0x041e, 0x3020): /* Creative SB Audigy 2 NX */
682		case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
683			/* doesn't set the sample rate attribute, but supports it */
684			fp->attributes |= UAC_EP_CS_ATTR_SAMPLE_RATE;
685			break;
686		case USB_ID(0x0763, 0x2001):  /* M-Audio Quattro USB */
687		case USB_ID(0x0763, 0x2012):  /* M-Audio Fast Track Pro USB */
688		case USB_ID(0x047f, 0x0ca1): /* plantronics headset */
689		case USB_ID(0x077d, 0x07af): /* Griffin iMic (note that there is
690						an older model 77d:223) */
691		/*
692		 * plantronics headset and Griffin iMic have set adaptive-in
693		 * although it's really not...
694		 */
695			fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
696			if (stream == SNDRV_PCM_STREAM_PLAYBACK)
697				fp->ep_attr |= USB_ENDPOINT_SYNC_ADAPTIVE;
698			else
699				fp->ep_attr |= USB_ENDPOINT_SYNC_SYNC;
700			break;
701		}
702
703		/* ok, let's parse further... */
704		if (snd_usb_parse_audio_format(chip, fp, format, fmt, stream) < 0) {
705			kfree(fp->rate_table);
706			kfree(fp);
707			fp = NULL;
708			continue;
709		}
710
711		/* Create chmap */
712		if (fp->channels != num_channels)
713			chconfig = 0;
714		fp->chmap = convert_chmap(fp->channels, chconfig, protocol);
715
716		dev_dbg(&dev->dev, "%u:%d: add audio endpoint %#x\n", iface_no, altno, fp->endpoint);
717		err = snd_usb_add_audio_stream(chip, stream, fp);
718		if (err < 0) {
719			kfree(fp->rate_table);
720			kfree(fp->chmap);
721			kfree(fp);
722			return err;
723		}
724		/* try to set the interface... */
725		usb_set_interface(chip->dev, iface_no, altno);
726		snd_usb_init_pitch(chip, iface_no, alts, fp);
727		snd_usb_init_sample_rate(chip, iface_no, alts, fp, fp->rate_max);
728	}
729	return 0;
730}
731