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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->tx_length_quirk = as->chip->tx_length_quirk;
 96	subs->speed = snd_usb_get_speed(subs->dev);
 97	subs->pkt_offset_adj = 0;
 98
 99	snd_usb_set_pcm_ops(as->pcm, stream);
100
101	list_add_tail(&fp->list, &subs->fmt_list);
102	subs->formats |= fp->formats;
103	subs->num_formats++;
104	subs->fmt_type = fp->fmt_type;
105	subs->ep_num = fp->endpoint;
106	if (fp->channels > subs->channels_max)
107		subs->channels_max = fp->channels;
108}
109
110/* kctl callbacks for usb-audio channel maps */
111static int usb_chmap_ctl_info(struct snd_kcontrol *kcontrol,
112			      struct snd_ctl_elem_info *uinfo)
113{
114	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
115	struct snd_usb_substream *subs = info->private_data;
116
117	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
118	uinfo->count = subs->channels_max;
119	uinfo->value.integer.min = 0;
120	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
121	return 0;
122}
123
124/* check whether a duplicated entry exists in the audiofmt list */
125static bool have_dup_chmap(struct snd_usb_substream *subs,
126			   struct audioformat *fp)
127{
128	struct audioformat *prev = fp;
129
130	list_for_each_entry_continue_reverse(prev, &subs->fmt_list, list) {
131		if (prev->chmap &&
132		    !memcmp(prev->chmap, fp->chmap, sizeof(*fp->chmap)))
133			return true;
134	}
135	return false;
136}
137
138static int usb_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
139			     unsigned int size, unsigned int __user *tlv)
140{
141	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
142	struct snd_usb_substream *subs = info->private_data;
143	struct audioformat *fp;
144	unsigned int __user *dst;
145	int count = 0;
146
147	if (size < 8)
148		return -ENOMEM;
149	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
150		return -EFAULT;
151	size -= 8;
152	dst = tlv + 2;
153	list_for_each_entry(fp, &subs->fmt_list, list) {
154		int i, ch_bytes;
155
156		if (!fp->chmap)
157			continue;
158		if (have_dup_chmap(subs, fp))
159			continue;
160		/* copy the entry */
161		ch_bytes = fp->chmap->channels * 4;
162		if (size < 8 + ch_bytes)
163			return -ENOMEM;
164		if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
165		    put_user(ch_bytes, dst + 1))
166			return -EFAULT;
167		dst += 2;
168		for (i = 0; i < fp->chmap->channels; i++, dst++) {
169			if (put_user(fp->chmap->map[i], dst))
170				return -EFAULT;
171		}
172
173		count += 8 + ch_bytes;
174		size -= 8 + ch_bytes;
175	}
176	if (put_user(count, tlv + 1))
177		return -EFAULT;
178	return 0;
179}
180
181static int usb_chmap_ctl_get(struct snd_kcontrol *kcontrol,
182			     struct snd_ctl_elem_value *ucontrol)
183{
184	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
185	struct snd_usb_substream *subs = info->private_data;
186	struct snd_pcm_chmap_elem *chmap = NULL;
187	int i;
188
189	memset(ucontrol->value.integer.value, 0,
190	       sizeof(ucontrol->value.integer.value));
191	if (subs->cur_audiofmt)
192		chmap = subs->cur_audiofmt->chmap;
193	if (chmap) {
194		for (i = 0; i < chmap->channels; i++)
195			ucontrol->value.integer.value[i] = chmap->map[i];
196	}
197	return 0;
198}
199
200/* create a chmap kctl assigned to the given USB substream */
201static int add_chmap(struct snd_pcm *pcm, int stream,
202		     struct snd_usb_substream *subs)
203{
204	struct audioformat *fp;
205	struct snd_pcm_chmap *chmap;
206	struct snd_kcontrol *kctl;
207	int err;
208
209	list_for_each_entry(fp, &subs->fmt_list, list)
210		if (fp->chmap)
211			goto ok;
212	/* no chmap is found */
213	return 0;
214
215 ok:
216	err = snd_pcm_add_chmap_ctls(pcm, stream, NULL, 0, 0, &chmap);
217	if (err < 0)
218		return err;
219
220	/* override handlers */
221	chmap->private_data = subs;
222	kctl = chmap->kctl;
223	kctl->info = usb_chmap_ctl_info;
224	kctl->get = usb_chmap_ctl_get;
225	kctl->tlv.c = usb_chmap_ctl_tlv;
226
227	return 0;
228}
229
230/* convert from USB ChannelConfig bits to ALSA chmap element */
231static struct snd_pcm_chmap_elem *convert_chmap(int channels, unsigned int bits,
232						int protocol)
233{
234	static unsigned int uac1_maps[] = {
235		SNDRV_CHMAP_FL,		/* left front */
236		SNDRV_CHMAP_FR,		/* right front */
237		SNDRV_CHMAP_FC,		/* center front */
238		SNDRV_CHMAP_LFE,	/* LFE */
239		SNDRV_CHMAP_SL,		/* left surround */
240		SNDRV_CHMAP_SR,		/* right surround */
241		SNDRV_CHMAP_FLC,	/* left of center */
242		SNDRV_CHMAP_FRC,	/* right of center */
243		SNDRV_CHMAP_RC,		/* surround */
244		SNDRV_CHMAP_SL,		/* side left */
245		SNDRV_CHMAP_SR,		/* side right */
246		SNDRV_CHMAP_TC,		/* top */
247		0 /* terminator */
248	};
249	static unsigned int uac2_maps[] = {
250		SNDRV_CHMAP_FL,		/* front left */
251		SNDRV_CHMAP_FR,		/* front right */
252		SNDRV_CHMAP_FC,		/* front center */
253		SNDRV_CHMAP_LFE,	/* LFE */
254		SNDRV_CHMAP_RL,		/* back left */
255		SNDRV_CHMAP_RR,		/* back right */
256		SNDRV_CHMAP_FLC,	/* front left of center */
257		SNDRV_CHMAP_FRC,	/* front right of center */
258		SNDRV_CHMAP_RC,		/* back center */
259		SNDRV_CHMAP_SL,		/* side left */
260		SNDRV_CHMAP_SR,		/* side right */
261		SNDRV_CHMAP_TC,		/* top center */
262		SNDRV_CHMAP_TFL,	/* top front left */
263		SNDRV_CHMAP_TFC,	/* top front center */
264		SNDRV_CHMAP_TFR,	/* top front right */
265		SNDRV_CHMAP_TRL,	/* top back left */
266		SNDRV_CHMAP_TRC,	/* top back center */
267		SNDRV_CHMAP_TRR,	/* top back right */
268		SNDRV_CHMAP_TFLC,	/* top front left of center */
269		SNDRV_CHMAP_TFRC,	/* top front right of center */
270		SNDRV_CHMAP_LLFE,	/* left LFE */
271		SNDRV_CHMAP_RLFE,	/* right LFE */
272		SNDRV_CHMAP_TSL,	/* top side left */
273		SNDRV_CHMAP_TSR,	/* top side right */
274		SNDRV_CHMAP_BC,		/* bottom center */
275		SNDRV_CHMAP_RLC,	/* back left of center */
276		SNDRV_CHMAP_RRC,	/* back right of center */
277		0 /* terminator */
278	};
279	struct snd_pcm_chmap_elem *chmap;
280	const unsigned int *maps;
281	int c;
282
283	if (channels > ARRAY_SIZE(chmap->map))
284		return NULL;
285
286	chmap = kzalloc(sizeof(*chmap), GFP_KERNEL);
287	if (!chmap)
288		return NULL;
289
290	maps = protocol == UAC_VERSION_2 ? uac2_maps : uac1_maps;
291	chmap->channels = channels;
292	c = 0;
293
294	if (bits) {
295		for (; bits && *maps; maps++, bits >>= 1)
296			if (bits & 1)
297				chmap->map[c++] = *maps;
298	} else {
299		/* If we're missing wChannelConfig, then guess something
300		    to make sure the channel map is not skipped entirely */
301		if (channels == 1)
302			chmap->map[c++] = SNDRV_CHMAP_MONO;
303		else
304			for (; c < channels && *maps; maps++)
305				chmap->map[c++] = *maps;
306	}
307
308	for (; c < channels; c++)
309		chmap->map[c] = SNDRV_CHMAP_UNKNOWN;
310
311	return chmap;
312}
313
314/*
315 * add this endpoint to the chip instance.
316 * if a stream with the same endpoint already exists, append to it.
317 * if not, create a new pcm stream. note, fp is added to the substream
318 * fmt_list and will be freed on the chip instance release. do not free
319 * fp or do remove it from the substream fmt_list to avoid double-free.
320 */
321int snd_usb_add_audio_stream(struct snd_usb_audio *chip,
322			     int stream,
323			     struct audioformat *fp)
324{
325	struct snd_usb_stream *as;
326	struct snd_usb_substream *subs;
327	struct snd_pcm *pcm;
328	int err;
329
330	list_for_each_entry(as, &chip->pcm_list, list) {
331		if (as->fmt_type != fp->fmt_type)
332			continue;
333		subs = &as->substream[stream];
334		if (subs->ep_num == fp->endpoint) {
335			list_add_tail(&fp->list, &subs->fmt_list);
336			subs->num_formats++;
337			subs->formats |= fp->formats;
338			return 0;
339		}
340	}
341	/* look for an empty stream */
342	list_for_each_entry(as, &chip->pcm_list, list) {
343		if (as->fmt_type != fp->fmt_type)
344			continue;
345		subs = &as->substream[stream];
346		if (subs->ep_num)
347			continue;
348		err = snd_pcm_new_stream(as->pcm, stream, 1);
349		if (err < 0)
350			return err;
351		snd_usb_init_substream(as, stream, fp);
352		return add_chmap(as->pcm, stream, subs);
353	}
354
355	/* create a new pcm */
356	as = kzalloc(sizeof(*as), GFP_KERNEL);
357	if (!as)
358		return -ENOMEM;
359	as->pcm_index = chip->pcm_devs;
360	as->chip = chip;
361	as->fmt_type = fp->fmt_type;
362	err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
363			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
364			  stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
365			  &pcm);
366	if (err < 0) {
367		kfree(as);
368		return err;
369	}
370	as->pcm = pcm;
371	pcm->private_data = as;
372	pcm->private_free = snd_usb_audio_pcm_free;
373	pcm->info_flags = 0;
374	if (chip->pcm_devs > 0)
375		sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
376	else
377		strcpy(pcm->name, "USB Audio");
378
379	snd_usb_init_substream(as, stream, fp);
380
381	/*
382	 * Keep using head insertion for M-Audio Audiophile USB (tm) which has a
383	 * fix to swap capture stream order in conf/cards/USB-audio.conf
384	 */
385	if (chip->usb_id == USB_ID(0x0763, 0x2003))
386		list_add(&as->list, &chip->pcm_list);
387	else
388		list_add_tail(&as->list, &chip->pcm_list);
389
390	chip->pcm_devs++;
391
392	snd_usb_proc_pcm_format_add(as);
393
394	return add_chmap(pcm, stream, &as->substream[stream]);
395}
396
397static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
398					 struct usb_host_interface *alts,
399					 int protocol, int iface_no)
400{
401	/* parsed with a v1 header here. that's ok as we only look at the
402	 * header first which is the same for both versions */
403	struct uac_iso_endpoint_descriptor *csep;
404	struct usb_interface_descriptor *altsd = get_iface_desc(alts);
405	int attributes = 0;
406
407	csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
408
409	/* Creamware Noah has this descriptor after the 2nd endpoint */
410	if (!csep && altsd->bNumEndpoints >= 2)
411		csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
412
413	/*
414	 * If we can't locate the USB_DT_CS_ENDPOINT descriptor in the extra
415	 * bytes after the first endpoint, go search the entire interface.
416	 * Some devices have it directly *before* the standard endpoint.
417	 */
418	if (!csep)
419		csep = snd_usb_find_desc(alts->extra, alts->extralen, NULL, USB_DT_CS_ENDPOINT);
420
421	if (!csep || csep->bLength < 7 ||
422	    csep->bDescriptorSubtype != UAC_EP_GENERAL) {
423		usb_audio_warn(chip,
424			       "%u:%d : no or invalid class specific endpoint descriptor\n",
425			       iface_no, altsd->bAlternateSetting);
426		return 0;
427	}
428
429	if (protocol == UAC_VERSION_1) {
430		attributes = csep->bmAttributes;
431	} else {
432		struct uac2_iso_endpoint_descriptor *csep2 =
433			(struct uac2_iso_endpoint_descriptor *) csep;
434
435		attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;
436
437		/* emulate the endpoint attributes of a v1 device */
438		if (csep2->bmControls & UAC2_CONTROL_PITCH)
439			attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
440	}
441
442	return attributes;
443}
444
445/* find an input terminal descriptor (either UAC1 or UAC2) with the given
446 * terminal id
447 */
448static void *
449snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
450					       int terminal_id)
451{
452	struct uac2_input_terminal_descriptor *term = NULL;
453
454	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
455					       ctrl_iface->extralen,
456					       term, UAC_INPUT_TERMINAL))) {
457		if (term->bTerminalID == terminal_id)
458			return term;
459	}
460
461	return NULL;
462}
463
464static struct uac2_output_terminal_descriptor *
465	snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
466						int terminal_id)
467{
468	struct uac2_output_terminal_descriptor *term = NULL;
469
470	while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
471					       ctrl_iface->extralen,
472					       term, UAC_OUTPUT_TERMINAL))) {
473		if (term->bTerminalID == terminal_id)
474			return term;
475	}
476
477	return NULL;
478}
479
480int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
481{
482	struct usb_device *dev;
483	struct usb_interface *iface;
484	struct usb_host_interface *alts;
485	struct usb_interface_descriptor *altsd;
486	int i, altno, err, stream;
487	unsigned int format = 0, num_channels = 0;
488	struct audioformat *fp = NULL;
489	int num, protocol, clock = 0;
490	struct uac_format_type_i_continuous_descriptor *fmt;
491	unsigned int chconfig;
492
493	dev = chip->dev;
494
495	/* parse the interface's altsettings */
496	iface = usb_ifnum_to_if(dev, iface_no);
497
498	num = iface->num_altsetting;
499
500	/*
501	 * Dallas DS4201 workaround: It presents 5 altsettings, but the last
502	 * one misses syncpipe, and does not produce any sound.
503	 */
504	if (chip->usb_id == USB_ID(0x04fa, 0x4201))
505		num = 4;
506
507	for (i = 0; i < num; i++) {
508		alts = &iface->altsetting[i];
509		altsd = get_iface_desc(alts);
510		protocol = altsd->bInterfaceProtocol;
511		/* skip invalid one */
512		if (((altsd->bInterfaceClass != USB_CLASS_AUDIO ||
513		      (altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING &&
514		       altsd->bInterfaceSubClass != USB_SUBCLASS_VENDOR_SPEC)) &&
515		     altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
516		    altsd->bNumEndpoints < 1 ||
517		    le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) == 0)
518			continue;
519		/* must be isochronous */
520		if ((get_endpoint(alts, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) !=
521		    USB_ENDPOINT_XFER_ISOC)
522			continue;
523		/* check direction */
524		stream = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN) ?
525			SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
526		altno = altsd->bAlternateSetting;
527
528		if (snd_usb_apply_interface_quirk(chip, iface_no, altno))
529			continue;
530
531		/*
532		 * Roland audio streaming interfaces are marked with protocols
533		 * 0/1/2, but are UAC 1 compatible.
534		 */
535		if (USB_ID_VENDOR(chip->usb_id) == 0x0582 &&
536		    altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
537		    protocol <= 2)
538			protocol = UAC_VERSION_1;
539
540		chconfig = 0;
541		/* get audio formats */
542		switch (protocol) {
543		default:
544			dev_dbg(&dev->dev, "%u:%d: unknown interface protocol %#02x, assuming v1\n",
545				iface_no, altno, protocol);
546			protocol = UAC_VERSION_1;
547			/* fall through */
548
549		case UAC_VERSION_1: {
550			struct uac1_as_header_descriptor *as =
551				snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
552			struct uac_input_terminal_descriptor *iterm;
553
554			if (!as) {
555				dev_err(&dev->dev,
556					"%u:%d : UAC_AS_GENERAL descriptor not found\n",
557					iface_no, altno);
558				continue;
559			}
560
561			if (as->bLength < sizeof(*as)) {
562				dev_err(&dev->dev,
563					"%u:%d : invalid UAC_AS_GENERAL desc\n",
564					iface_no, altno);
565				continue;
566			}
567
568			format = le16_to_cpu(as->wFormatTag); /* remember the format value */
569
570			iterm = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
571								       as->bTerminalLink);
572			if (iterm) {
573				num_channels = iterm->bNrChannels;
574				chconfig = le16_to_cpu(iterm->wChannelConfig);
575			}
576
577			break;
578		}
579
580		case UAC_VERSION_2: {
581			struct uac2_input_terminal_descriptor *input_term;
582			struct uac2_output_terminal_descriptor *output_term;
583			struct uac2_as_header_descriptor *as =
584				snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
585
586			if (!as) {
587				dev_err(&dev->dev,
588					"%u:%d : UAC_AS_GENERAL descriptor not found\n",
589					iface_no, altno);
590				continue;
591			}
592
593			if (as->bLength < sizeof(*as)) {
594				dev_err(&dev->dev,
595					"%u:%d : invalid UAC_AS_GENERAL desc\n",
596					iface_no, altno);
597				continue;
598			}
599
600			num_channels = as->bNrChannels;
601			format = le32_to_cpu(as->bmFormats);
602			chconfig = le32_to_cpu(as->bmChannelConfig);
603
604			/* lookup the terminal associated to this interface
605			 * to extract the clock */
606			input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
607									    as->bTerminalLink);
608			if (input_term) {
609				clock = input_term->bCSourceID;
610				if (!chconfig && (num_channels == input_term->bNrChannels))
611					chconfig = le32_to_cpu(input_term->bmChannelConfig);
612				break;
613			}
614
615			output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
616									      as->bTerminalLink);
617			if (output_term) {
618				clock = output_term->bCSourceID;
619				break;
620			}
621
622			dev_err(&dev->dev,
623				"%u:%d : bogus bTerminalLink %d\n",
624				iface_no, altno, as->bTerminalLink);
625			continue;
626		}
627		}
628
629		/* get format type */
630		fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_FORMAT_TYPE);
631		if (!fmt) {
632			dev_err(&dev->dev,
633				"%u:%d : no UAC_FORMAT_TYPE desc\n",
634				iface_no, altno);
635			continue;
636		}
637		if (((protocol == UAC_VERSION_1) && (fmt->bLength < 8)) ||
638		    ((protocol == UAC_VERSION_2) && (fmt->bLength < 6))) {
639			dev_err(&dev->dev,
640				"%u:%d : invalid UAC_FORMAT_TYPE desc\n",
641				iface_no, altno);
642			continue;
643		}
644
645		/*
646		 * Blue Microphones workaround: The last altsetting is identical
647		 * with the previous one, except for a larger packet size, but
648		 * is actually a mislabeled two-channel setting; ignore it.
649		 */
650		if (fmt->bNrChannels == 1 &&
651		    fmt->bSubframeSize == 2 &&
652		    altno == 2 && num == 3 &&
653		    fp && fp->altsetting == 1 && fp->channels == 1 &&
654		    fp->formats == SNDRV_PCM_FMTBIT_S16_LE &&
655		    protocol == UAC_VERSION_1 &&
656		    le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) ==
657							fp->maxpacksize * 2)
658			continue;
659
660		fp = kzalloc(sizeof(*fp), GFP_KERNEL);
661		if (! fp) {
662			dev_err(&dev->dev, "cannot malloc\n");
663			return -ENOMEM;
664		}
665
666		fp->iface = iface_no;
667		fp->altsetting = altno;
668		fp->altset_idx = i;
669		fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
670		fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
671		fp->datainterval = snd_usb_parse_datainterval(chip, alts);
672		fp->protocol = protocol;
673		fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
674		fp->channels = num_channels;
675		if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
676			fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
677					* (fp->maxpacksize & 0x7ff);
678		fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
679		fp->clock = clock;
680		INIT_LIST_HEAD(&fp->list);
681
682		/* some quirks for attributes here */
683
684		switch (chip->usb_id) {
685		case USB_ID(0x0a92, 0x0053): /* AudioTrak Optoplay */
686			/* Optoplay sets the sample rate attribute although
687			 * it seems not supporting it in fact.
688			 */
689			fp->attributes &= ~UAC_EP_CS_ATTR_SAMPLE_RATE;
690			break;
691		case USB_ID(0x041e, 0x3020): /* Creative SB Audigy 2 NX */
692		case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
693			/* doesn't set the sample rate attribute, but supports it */
694			fp->attributes |= UAC_EP_CS_ATTR_SAMPLE_RATE;
695			break;
696		case USB_ID(0x0763, 0x2001):  /* M-Audio Quattro USB */
697		case USB_ID(0x0763, 0x2012):  /* M-Audio Fast Track Pro USB */
698		case USB_ID(0x047f, 0x0ca1): /* plantronics headset */
699		case USB_ID(0x077d, 0x07af): /* Griffin iMic (note that there is
700						an older model 77d:223) */
701		/*
702		 * plantronics headset and Griffin iMic have set adaptive-in
703		 * although it's really not...
704		 */
705			fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
706			if (stream == SNDRV_PCM_STREAM_PLAYBACK)
707				fp->ep_attr |= USB_ENDPOINT_SYNC_ADAPTIVE;
708			else
709				fp->ep_attr |= USB_ENDPOINT_SYNC_SYNC;
710			break;
711		}
712
713		/* ok, let's parse further... */
714		if (snd_usb_parse_audio_format(chip, fp, format, fmt, stream) < 0) {
715			kfree(fp->rate_table);
716			kfree(fp);
717			fp = NULL;
718			continue;
719		}
720
721		/* Create chmap */
722		if (fp->channels != num_channels)
723			chconfig = 0;
724		fp->chmap = convert_chmap(fp->channels, chconfig, protocol);
725
726		dev_dbg(&dev->dev, "%u:%d: add audio endpoint %#x\n", iface_no, altno, fp->endpoint);
727		err = snd_usb_add_audio_stream(chip, stream, fp);
728		if (err < 0) {
729			list_del(&fp->list); /* unlink for avoiding double-free */
730			kfree(fp->rate_table);
731			kfree(fp->chmap);
732			kfree(fp);
733			return err;
734		}
735		/* try to set the interface... */
736		usb_set_interface(chip->dev, iface_no, altno);
737		snd_usb_init_pitch(chip, iface_no, alts, fp);
738		snd_usb_init_sample_rate(chip, iface_no, alts, fp, fp->rate_max);
739	}
740	return 0;
741}
742