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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
27#include "usbaudio.h"
28#include "card.h"
29#include "proc.h"
30#include "quirks.h"
31#include "endpoint.h"
32#include "urb.h"
33#include "pcm.h"
34#include "helper.h"
35#include "format.h"
36#include "clock.h"
37
38/*
39 * free a substream
40 */
41static void free_substream(struct snd_usb_substream *subs)
42{
43 struct list_head *p, *n;
44
45 if (!subs->num_formats)
46 return; /* not initialized */
47 list_for_each_safe(p, n, &subs->fmt_list) {
48 struct audioformat *fp = list_entry(p, struct audioformat, list);
49 kfree(fp->rate_table);
50 kfree(fp);
51 }
52 kfree(subs->rate_list.list);
53}
54
55
56/*
57 * free a usb stream instance
58 */
59static void snd_usb_audio_stream_free(struct snd_usb_stream *stream)
60{
61 free_substream(&stream->substream[0]);
62 free_substream(&stream->substream[1]);
63 list_del(&stream->list);
64 kfree(stream);
65}
66
67static void snd_usb_audio_pcm_free(struct snd_pcm *pcm)
68{
69 struct snd_usb_stream *stream = pcm->private_data;
70 if (stream) {
71 stream->pcm = NULL;
72 snd_usb_audio_stream_free(stream);
73 }
74}
75
76
77/*
78 * add this endpoint to the chip instance.
79 * if a stream with the same endpoint already exists, append to it.
80 * if not, create a new pcm stream.
81 */
82int snd_usb_add_audio_endpoint(struct snd_usb_audio *chip, int stream, struct audioformat *fp)
83{
84 struct list_head *p;
85 struct snd_usb_stream *as;
86 struct snd_usb_substream *subs;
87 struct snd_pcm *pcm;
88 int err;
89
90 list_for_each(p, &chip->pcm_list) {
91 as = list_entry(p, struct snd_usb_stream, list);
92 if (as->fmt_type != fp->fmt_type)
93 continue;
94 subs = &as->substream[stream];
95 if (!subs->endpoint)
96 continue;
97 if (subs->endpoint == fp->endpoint) {
98 list_add_tail(&fp->list, &subs->fmt_list);
99 subs->num_formats++;
100 subs->formats |= fp->formats;
101 return 0;
102 }
103 }
104 /* look for an empty stream */
105 list_for_each(p, &chip->pcm_list) {
106 as = list_entry(p, struct snd_usb_stream, list);
107 if (as->fmt_type != fp->fmt_type)
108 continue;
109 subs = &as->substream[stream];
110 if (subs->endpoint)
111 continue;
112 err = snd_pcm_new_stream(as->pcm, stream, 1);
113 if (err < 0)
114 return err;
115 snd_usb_init_substream(as, stream, fp);
116 return 0;
117 }
118
119 /* create a new pcm */
120 as = kzalloc(sizeof(*as), GFP_KERNEL);
121 if (!as)
122 return -ENOMEM;
123 as->pcm_index = chip->pcm_devs;
124 as->chip = chip;
125 as->fmt_type = fp->fmt_type;
126 err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
127 stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
128 stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
129 &pcm);
130 if (err < 0) {
131 kfree(as);
132 return err;
133 }
134 as->pcm = pcm;
135 pcm->private_data = as;
136 pcm->private_free = snd_usb_audio_pcm_free;
137 pcm->info_flags = 0;
138 if (chip->pcm_devs > 0)
139 sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
140 else
141 strcpy(pcm->name, "USB Audio");
142
143 snd_usb_init_substream(as, stream, fp);
144
145 list_add(&as->list, &chip->pcm_list);
146 chip->pcm_devs++;
147
148 snd_usb_proc_pcm_format_add(as);
149
150 return 0;
151}
152
153static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
154 struct usb_host_interface *alts,
155 int protocol, int iface_no)
156{
157 /* parsed with a v1 header here. that's ok as we only look at the
158 * header first which is the same for both versions */
159 struct uac_iso_endpoint_descriptor *csep;
160 struct usb_interface_descriptor *altsd = get_iface_desc(alts);
161 int attributes = 0;
162
163 csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
164
165 /* Creamware Noah has this descriptor after the 2nd endpoint */
166 if (!csep && altsd->bNumEndpoints >= 2)
167 csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
168
169 if (!csep || csep->bLength < 7 ||
170 csep->bDescriptorSubtype != UAC_EP_GENERAL) {
171 snd_printk(KERN_WARNING "%d:%u:%d : no or invalid"
172 " class specific endpoint descriptor\n",
173 chip->dev->devnum, iface_no,
174 altsd->bAlternateSetting);
175 return 0;
176 }
177
178 if (protocol == UAC_VERSION_1) {
179 attributes = csep->bmAttributes;
180 } else {
181 struct uac2_iso_endpoint_descriptor *csep2 =
182 (struct uac2_iso_endpoint_descriptor *) csep;
183
184 attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;
185
186 /* emulate the endpoint attributes of a v1 device */
187 if (csep2->bmControls & UAC2_CONTROL_PITCH)
188 attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
189 }
190
191 return attributes;
192}
193
194static struct uac2_input_terminal_descriptor *
195 snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
196 int terminal_id)
197{
198 struct uac2_input_terminal_descriptor *term = NULL;
199
200 while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
201 ctrl_iface->extralen,
202 term, UAC_INPUT_TERMINAL))) {
203 if (term->bTerminalID == terminal_id)
204 return term;
205 }
206
207 return NULL;
208}
209
210static struct uac2_output_terminal_descriptor *
211 snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
212 int terminal_id)
213{
214 struct uac2_output_terminal_descriptor *term = NULL;
215
216 while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
217 ctrl_iface->extralen,
218 term, UAC_OUTPUT_TERMINAL))) {
219 if (term->bTerminalID == terminal_id)
220 return term;
221 }
222
223 return NULL;
224}
225
226int snd_usb_parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
227{
228 struct usb_device *dev;
229 struct usb_interface *iface;
230 struct usb_host_interface *alts;
231 struct usb_interface_descriptor *altsd;
232 int i, altno, err, stream;
233 int format = 0, num_channels = 0;
234 struct audioformat *fp = NULL;
235 int num, protocol, clock = 0;
236 struct uac_format_type_i_continuous_descriptor *fmt;
237
238 dev = chip->dev;
239
240 /* parse the interface's altsettings */
241 iface = usb_ifnum_to_if(dev, iface_no);
242
243 num = iface->num_altsetting;
244
245 /*
246 * Dallas DS4201 workaround: It presents 5 altsettings, but the last
247 * one misses syncpipe, and does not produce any sound.
248 */
249 if (chip->usb_id == USB_ID(0x04fa, 0x4201))
250 num = 4;
251
252 for (i = 0; i < num; i++) {
253 alts = &iface->altsetting[i];
254 altsd = get_iface_desc(alts);
255 protocol = altsd->bInterfaceProtocol;
256 /* skip invalid one */
257 if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
258 altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
259 (altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING &&
260 altsd->bInterfaceSubClass != USB_SUBCLASS_VENDOR_SPEC) ||
261 altsd->bNumEndpoints < 1 ||
262 le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) == 0)
263 continue;
264 /* must be isochronous */
265 if ((get_endpoint(alts, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) !=
266 USB_ENDPOINT_XFER_ISOC)
267 continue;
268 /* check direction */
269 stream = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN) ?
270 SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
271 altno = altsd->bAlternateSetting;
272
273 if (snd_usb_apply_interface_quirk(chip, iface_no, altno))
274 continue;
275
276 /* get audio formats */
277 switch (protocol) {
278 default:
279 snd_printdd(KERN_WARNING "%d:%u:%d: unknown interface protocol %#02x, assuming v1\n",
280 dev->devnum, iface_no, altno, protocol);
281 protocol = UAC_VERSION_1;
282 /* fall through */
283
284 case UAC_VERSION_1: {
285 struct uac1_as_header_descriptor *as =
286 snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
287
288 if (!as) {
289 snd_printk(KERN_ERR "%d:%u:%d : UAC_AS_GENERAL descriptor not found\n",
290 dev->devnum, iface_no, altno);
291 continue;
292 }
293
294 if (as->bLength < sizeof(*as)) {
295 snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_AS_GENERAL desc\n",
296 dev->devnum, iface_no, altno);
297 continue;
298 }
299
300 format = le16_to_cpu(as->wFormatTag); /* remember the format value */
301 break;
302 }
303
304 case UAC_VERSION_2: {
305 struct uac2_input_terminal_descriptor *input_term;
306 struct uac2_output_terminal_descriptor *output_term;
307 struct uac2_as_header_descriptor *as =
308 snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
309
310 if (!as) {
311 snd_printk(KERN_ERR "%d:%u:%d : UAC_AS_GENERAL descriptor not found\n",
312 dev->devnum, iface_no, altno);
313 continue;
314 }
315
316 if (as->bLength < sizeof(*as)) {
317 snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_AS_GENERAL desc\n",
318 dev->devnum, iface_no, altno);
319 continue;
320 }
321
322 num_channels = as->bNrChannels;
323 format = le32_to_cpu(as->bmFormats);
324
325 /* lookup the terminal associated to this interface
326 * to extract the clock */
327 input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
328 as->bTerminalLink);
329 if (input_term) {
330 clock = input_term->bCSourceID;
331 break;
332 }
333
334 output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
335 as->bTerminalLink);
336 if (output_term) {
337 clock = output_term->bCSourceID;
338 break;
339 }
340
341 snd_printk(KERN_ERR "%d:%u:%d : bogus bTerminalLink %d\n",
342 dev->devnum, iface_no, altno, as->bTerminalLink);
343 continue;
344 }
345 }
346
347 /* get format type */
348 fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_FORMAT_TYPE);
349 if (!fmt) {
350 snd_printk(KERN_ERR "%d:%u:%d : no UAC_FORMAT_TYPE desc\n",
351 dev->devnum, iface_no, altno);
352 continue;
353 }
354 if (((protocol == UAC_VERSION_1) && (fmt->bLength < 8)) ||
355 ((protocol == UAC_VERSION_2) && (fmt->bLength < 6))) {
356 snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_FORMAT_TYPE desc\n",
357 dev->devnum, iface_no, altno);
358 continue;
359 }
360
361 /*
362 * Blue Microphones workaround: The last altsetting is identical
363 * with the previous one, except for a larger packet size, but
364 * is actually a mislabeled two-channel setting; ignore it.
365 */
366 if (fmt->bNrChannels == 1 &&
367 fmt->bSubframeSize == 2 &&
368 altno == 2 && num == 3 &&
369 fp && fp->altsetting == 1 && fp->channels == 1 &&
370 fp->formats == SNDRV_PCM_FMTBIT_S16_LE &&
371 protocol == UAC_VERSION_1 &&
372 le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) ==
373 fp->maxpacksize * 2)
374 continue;
375
376 fp = kzalloc(sizeof(*fp), GFP_KERNEL);
377 if (! fp) {
378 snd_printk(KERN_ERR "cannot malloc\n");
379 return -ENOMEM;
380 }
381
382 fp->iface = iface_no;
383 fp->altsetting = altno;
384 fp->altset_idx = i;
385 fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
386 fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
387 fp->datainterval = snd_usb_parse_datainterval(chip, alts);
388 fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
389 /* num_channels is only set for v2 interfaces */
390 fp->channels = num_channels;
391 if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
392 fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
393 * (fp->maxpacksize & 0x7ff);
394 fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
395 fp->clock = clock;
396
397 /* some quirks for attributes here */
398
399 switch (chip->usb_id) {
400 case USB_ID(0x0a92, 0x0053): /* AudioTrak Optoplay */
401 /* Optoplay sets the sample rate attribute although
402 * it seems not supporting it in fact.
403 */
404 fp->attributes &= ~UAC_EP_CS_ATTR_SAMPLE_RATE;
405 break;
406 case USB_ID(0x041e, 0x3020): /* Creative SB Audigy 2 NX */
407 case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
408 /* doesn't set the sample rate attribute, but supports it */
409 fp->attributes |= UAC_EP_CS_ATTR_SAMPLE_RATE;
410 break;
411 case USB_ID(0x0763, 0x2001): /* M-Audio Quattro USB */
412 case USB_ID(0x0763, 0x2012): /* M-Audio Fast Track Pro USB */
413 case USB_ID(0x047f, 0x0ca1): /* plantronics headset */
414 case USB_ID(0x077d, 0x07af): /* Griffin iMic (note that there is
415 an older model 77d:223) */
416 /*
417 * plantronics headset and Griffin iMic have set adaptive-in
418 * although it's really not...
419 */
420 fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
421 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
422 fp->ep_attr |= USB_ENDPOINT_SYNC_ADAPTIVE;
423 else
424 fp->ep_attr |= USB_ENDPOINT_SYNC_SYNC;
425 break;
426 }
427
428 /* ok, let's parse further... */
429 if (snd_usb_parse_audio_format(chip, fp, format, fmt, stream, alts) < 0) {
430 kfree(fp->rate_table);
431 kfree(fp);
432 fp = NULL;
433 continue;
434 }
435
436 snd_printdd(KERN_INFO "%d:%u:%d: add audio endpoint %#x\n", dev->devnum, iface_no, altno, fp->endpoint);
437 err = snd_usb_add_audio_endpoint(chip, stream, fp);
438 if (err < 0) {
439 kfree(fp->rate_table);
440 kfree(fp);
441 return err;
442 }
443 /* try to set the interface... */
444 usb_set_interface(chip->dev, iface_no, altno);
445 snd_usb_init_pitch(chip, iface_no, alts, fp);
446 snd_usb_init_sample_rate(chip, iface_no, alts, fp, fp->rate_max);
447 }
448 return 0;
449}
450
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/gfp.h>
19#include <linux/init.h>
20#include <linux/ratelimit.h>
21#include <linux/usb.h>
22#include <linux/usb/audio.h>
23#include <linux/slab.h>
24
25#include <sound/core.h>
26#include <sound/pcm.h>
27#include <sound/pcm_params.h>
28
29#include "usbaudio.h"
30#include "helper.h"
31#include "card.h"
32#include "endpoint.h"
33#include "pcm.h"
34
35#define EP_FLAG_ACTIVATED 0
36#define EP_FLAG_RUNNING 1
37
38/*
39 * snd_usb_endpoint is a model that abstracts everything related to an
40 * USB endpoint and its streaming.
41 *
42 * There are functions to activate and deactivate the streaming URBs and
43 * optional callbacks to let the pcm logic handle the actual content of the
44 * packets for playback and record. Thus, the bus streaming and the audio
45 * handlers are fully decoupled.
46 *
47 * There are two different types of endpoints in audio applications.
48 *
49 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
50 * inbound and outbound traffic.
51 *
52 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
53 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
54 * (3 or 4 bytes).
55 *
56 * Each endpoint has to be configured prior to being used by calling
57 * snd_usb_endpoint_set_params().
58 *
59 * The model incorporates a reference counting, so that multiple users
60 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
61 * only the first user will effectively start the URBs, and only the last
62 * one to stop it will tear the URBs down again.
63 */
64
65/*
66 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
67 * this will overflow at approx 524 kHz
68 */
69static inline unsigned get_usb_full_speed_rate(unsigned int rate)
70{
71 return ((rate << 13) + 62) / 125;
72}
73
74/*
75 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
76 * this will overflow at approx 4 MHz
77 */
78static inline unsigned get_usb_high_speed_rate(unsigned int rate)
79{
80 return ((rate << 10) + 62) / 125;
81}
82
83/*
84 * release a urb data
85 */
86static void release_urb_ctx(struct snd_urb_ctx *u)
87{
88 if (u->buffer_size)
89 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
90 u->urb->transfer_buffer,
91 u->urb->transfer_dma);
92 usb_free_urb(u->urb);
93 u->urb = NULL;
94}
95
96static const char *usb_error_string(int err)
97{
98 switch (err) {
99 case -ENODEV:
100 return "no device";
101 case -ENOENT:
102 return "endpoint not enabled";
103 case -EPIPE:
104 return "endpoint stalled";
105 case -ENOSPC:
106 return "not enough bandwidth";
107 case -ESHUTDOWN:
108 return "device disabled";
109 case -EHOSTUNREACH:
110 return "device suspended";
111 case -EINVAL:
112 case -EAGAIN:
113 case -EFBIG:
114 case -EMSGSIZE:
115 return "internal error";
116 default:
117 return "unknown error";
118 }
119}
120
121/**
122 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
123 *
124 * @ep: The snd_usb_endpoint
125 *
126 * Determine whether an endpoint is driven by an implicit feedback
127 * data endpoint source.
128 */
129int snd_usb_endpoint_implict_feedback_sink(struct snd_usb_endpoint *ep)
130{
131 return ep->sync_master &&
132 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA &&
133 ep->type == SND_USB_ENDPOINT_TYPE_DATA &&
134 usb_pipeout(ep->pipe);
135}
136
137/*
138 * For streaming based on information derived from sync endpoints,
139 * prepare_outbound_urb_sizes() will call next_packet_size() to
140 * determine the number of samples to be sent in the next packet.
141 *
142 * For implicit feedback, next_packet_size() is unused.
143 */
144int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
145{
146 unsigned long flags;
147 int ret;
148
149 if (ep->fill_max)
150 return ep->maxframesize;
151
152 spin_lock_irqsave(&ep->lock, flags);
153 ep->phase = (ep->phase & 0xffff)
154 + (ep->freqm << ep->datainterval);
155 ret = min(ep->phase >> 16, ep->maxframesize);
156 spin_unlock_irqrestore(&ep->lock, flags);
157
158 return ret;
159}
160
161static void retire_outbound_urb(struct snd_usb_endpoint *ep,
162 struct snd_urb_ctx *urb_ctx)
163{
164 if (ep->retire_data_urb)
165 ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
166}
167
168static void retire_inbound_urb(struct snd_usb_endpoint *ep,
169 struct snd_urb_ctx *urb_ctx)
170{
171 struct urb *urb = urb_ctx->urb;
172
173 if (ep->sync_slave)
174 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
175
176 if (ep->retire_data_urb)
177 ep->retire_data_urb(ep->data_subs, urb);
178}
179
180/*
181 * Prepare a PLAYBACK urb for submission to the bus.
182 */
183static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
184 struct snd_urb_ctx *ctx)
185{
186 int i;
187 struct urb *urb = ctx->urb;
188 unsigned char *cp = urb->transfer_buffer;
189
190 urb->dev = ep->chip->dev; /* we need to set this at each time */
191
192 switch (ep->type) {
193 case SND_USB_ENDPOINT_TYPE_DATA:
194 if (ep->prepare_data_urb) {
195 ep->prepare_data_urb(ep->data_subs, urb);
196 } else {
197 /* no data provider, so send silence */
198 unsigned int offs = 0;
199 for (i = 0; i < ctx->packets; ++i) {
200 int counts;
201
202 if (ctx->packet_size[i])
203 counts = ctx->packet_size[i];
204 else
205 counts = snd_usb_endpoint_next_packet_size(ep);
206
207 urb->iso_frame_desc[i].offset = offs * ep->stride;
208 urb->iso_frame_desc[i].length = counts * ep->stride;
209 offs += counts;
210 }
211
212 urb->number_of_packets = ctx->packets;
213 urb->transfer_buffer_length = offs * ep->stride;
214 memset(urb->transfer_buffer, ep->silence_value,
215 offs * ep->stride);
216 }
217 break;
218
219 case SND_USB_ENDPOINT_TYPE_SYNC:
220 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
221 /*
222 * fill the length and offset of each urb descriptor.
223 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
224 */
225 urb->iso_frame_desc[0].length = 4;
226 urb->iso_frame_desc[0].offset = 0;
227 cp[0] = ep->freqn;
228 cp[1] = ep->freqn >> 8;
229 cp[2] = ep->freqn >> 16;
230 cp[3] = ep->freqn >> 24;
231 } else {
232 /*
233 * fill the length and offset of each urb descriptor.
234 * the fixed 10.14 frequency is passed through the pipe.
235 */
236 urb->iso_frame_desc[0].length = 3;
237 urb->iso_frame_desc[0].offset = 0;
238 cp[0] = ep->freqn >> 2;
239 cp[1] = ep->freqn >> 10;
240 cp[2] = ep->freqn >> 18;
241 }
242
243 break;
244 }
245}
246
247/*
248 * Prepare a CAPTURE or SYNC urb for submission to the bus.
249 */
250static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
251 struct snd_urb_ctx *urb_ctx)
252{
253 int i, offs;
254 struct urb *urb = urb_ctx->urb;
255
256 urb->dev = ep->chip->dev; /* we need to set this at each time */
257
258 switch (ep->type) {
259 case SND_USB_ENDPOINT_TYPE_DATA:
260 offs = 0;
261 for (i = 0; i < urb_ctx->packets; i++) {
262 urb->iso_frame_desc[i].offset = offs;
263 urb->iso_frame_desc[i].length = ep->curpacksize;
264 offs += ep->curpacksize;
265 }
266
267 urb->transfer_buffer_length = offs;
268 urb->number_of_packets = urb_ctx->packets;
269 break;
270
271 case SND_USB_ENDPOINT_TYPE_SYNC:
272 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
273 urb->iso_frame_desc[0].offset = 0;
274 break;
275 }
276}
277
278/*
279 * Send output urbs that have been prepared previously. URBs are dequeued
280 * from ep->ready_playback_urbs and in case there there aren't any available
281 * or there are no packets that have been prepared, this function does
282 * nothing.
283 *
284 * The reason why the functionality of sending and preparing URBs is separated
285 * is that host controllers don't guarantee the order in which they return
286 * inbound and outbound packets to their submitters.
287 *
288 * This function is only used for implicit feedback endpoints. For endpoints
289 * driven by dedicated sync endpoints, URBs are immediately re-submitted
290 * from their completion handler.
291 */
292static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
293{
294 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
295
296 unsigned long flags;
297 struct snd_usb_packet_info *uninitialized_var(packet);
298 struct snd_urb_ctx *ctx = NULL;
299 struct urb *urb;
300 int err, i;
301
302 spin_lock_irqsave(&ep->lock, flags);
303 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
304 packet = ep->next_packet + ep->next_packet_read_pos;
305 ep->next_packet_read_pos++;
306 ep->next_packet_read_pos %= MAX_URBS;
307
308 /* take URB out of FIFO */
309 if (!list_empty(&ep->ready_playback_urbs))
310 ctx = list_first_entry(&ep->ready_playback_urbs,
311 struct snd_urb_ctx, ready_list);
312 }
313 spin_unlock_irqrestore(&ep->lock, flags);
314
315 if (ctx == NULL)
316 return;
317
318 list_del_init(&ctx->ready_list);
319 urb = ctx->urb;
320
321 /* copy over the length information */
322 for (i = 0; i < packet->packets; i++)
323 ctx->packet_size[i] = packet->packet_size[i];
324
325 /* call the data handler to fill in playback data */
326 prepare_outbound_urb(ep, ctx);
327
328 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
329 if (err < 0)
330 snd_printk(KERN_ERR "Unable to submit urb #%d: %d (urb %p)\n",
331 ctx->index, err, ctx->urb);
332 else
333 set_bit(ctx->index, &ep->active_mask);
334 }
335}
336
337/*
338 * complete callback for urbs
339 */
340static void snd_complete_urb(struct urb *urb)
341{
342 struct snd_urb_ctx *ctx = urb->context;
343 struct snd_usb_endpoint *ep = ctx->ep;
344 int err;
345
346 if (unlikely(urb->status == -ENOENT || /* unlinked */
347 urb->status == -ENODEV || /* device removed */
348 urb->status == -ECONNRESET || /* unlinked */
349 urb->status == -ESHUTDOWN || /* device disabled */
350 ep->chip->shutdown)) /* device disconnected */
351 goto exit_clear;
352
353 if (usb_pipeout(ep->pipe)) {
354 retire_outbound_urb(ep, ctx);
355 /* can be stopped during retire callback */
356 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
357 goto exit_clear;
358
359 if (snd_usb_endpoint_implict_feedback_sink(ep)) {
360 unsigned long flags;
361
362 spin_lock_irqsave(&ep->lock, flags);
363 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
364 spin_unlock_irqrestore(&ep->lock, flags);
365 queue_pending_output_urbs(ep);
366
367 goto exit_clear;
368 }
369
370 prepare_outbound_urb(ep, ctx);
371 } else {
372 retire_inbound_urb(ep, ctx);
373 /* can be stopped during retire callback */
374 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
375 goto exit_clear;
376
377 prepare_inbound_urb(ep, ctx);
378 }
379
380 err = usb_submit_urb(urb, GFP_ATOMIC);
381 if (err == 0)
382 return;
383
384 snd_printk(KERN_ERR "cannot submit urb (err = %d)\n", err);
385 //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
386
387exit_clear:
388 clear_bit(ctx->index, &ep->active_mask);
389}
390
391/**
392 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
393 *
394 * @chip: The chip
395 * @alts: The USB host interface
396 * @ep_num: The number of the endpoint to use
397 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
398 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
399 *
400 * If the requested endpoint has not been added to the given chip before,
401 * a new instance is created. Otherwise, a pointer to the previoulsy
402 * created instance is returned. In case of any error, NULL is returned.
403 *
404 * New endpoints will be added to chip->ep_list and must be freed by
405 * calling snd_usb_endpoint_free().
406 */
407struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
408 struct usb_host_interface *alts,
409 int ep_num, int direction, int type)
410{
411 struct list_head *p;
412 struct snd_usb_endpoint *ep;
413 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
414
415 mutex_lock(&chip->mutex);
416
417 list_for_each(p, &chip->ep_list) {
418 ep = list_entry(p, struct snd_usb_endpoint, list);
419 if (ep->ep_num == ep_num &&
420 ep->iface == alts->desc.bInterfaceNumber &&
421 ep->alt_idx == alts->desc.bAlternateSetting) {
422 snd_printdd(KERN_DEBUG "Re-using EP %x in iface %d,%d @%p\n",
423 ep_num, ep->iface, ep->alt_idx, ep);
424 goto __exit_unlock;
425 }
426 }
427
428 snd_printdd(KERN_DEBUG "Creating new %s %s endpoint #%x\n",
429 is_playback ? "playback" : "capture",
430 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
431 ep_num);
432
433 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
434 if (!ep)
435 goto __exit_unlock;
436
437 ep->chip = chip;
438 spin_lock_init(&ep->lock);
439 ep->type = type;
440 ep->ep_num = ep_num;
441 ep->iface = alts->desc.bInterfaceNumber;
442 ep->alt_idx = alts->desc.bAlternateSetting;
443 INIT_LIST_HEAD(&ep->ready_playback_urbs);
444 ep_num &= USB_ENDPOINT_NUMBER_MASK;
445
446 if (is_playback)
447 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
448 else
449 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
450
451 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
452 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
453 get_endpoint(alts, 1)->bRefresh >= 1 &&
454 get_endpoint(alts, 1)->bRefresh <= 9)
455 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
456 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
457 ep->syncinterval = 1;
458 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
459 get_endpoint(alts, 1)->bInterval <= 16)
460 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
461 else
462 ep->syncinterval = 3;
463
464 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
465 }
466
467 list_add_tail(&ep->list, &chip->ep_list);
468
469__exit_unlock:
470 mutex_unlock(&chip->mutex);
471
472 return ep;
473}
474
475/*
476 * wait until all urbs are processed.
477 */
478static int wait_clear_urbs(struct snd_usb_endpoint *ep)
479{
480 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
481 unsigned int i;
482 int alive;
483
484 do {
485 alive = 0;
486 for (i = 0; i < ep->nurbs; i++)
487 if (test_bit(i, &ep->active_mask))
488 alive++;
489
490 if (!alive)
491 break;
492
493 schedule_timeout_uninterruptible(1);
494 } while (time_before(jiffies, end_time));
495
496 if (alive)
497 snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n",
498 alive, ep->ep_num);
499
500 return 0;
501}
502
503/*
504 * unlink active urbs.
505 */
506static int deactivate_urbs(struct snd_usb_endpoint *ep, int force, int can_sleep)
507{
508 unsigned int i;
509 int async;
510
511 if (!force && ep->chip->shutdown) /* to be sure... */
512 return -EBADFD;
513
514 async = !can_sleep && ep->chip->async_unlink;
515
516 clear_bit(EP_FLAG_RUNNING, &ep->flags);
517
518 INIT_LIST_HEAD(&ep->ready_playback_urbs);
519 ep->next_packet_read_pos = 0;
520 ep->next_packet_write_pos = 0;
521
522 if (!async && in_interrupt())
523 return 0;
524
525 for (i = 0; i < ep->nurbs; i++) {
526 if (test_bit(i, &ep->active_mask)) {
527 if (!test_and_set_bit(i, &ep->unlink_mask)) {
528 struct urb *u = ep->urb[i].urb;
529 if (async)
530 usb_unlink_urb(u);
531 else
532 usb_kill_urb(u);
533 }
534 }
535 }
536
537 return 0;
538}
539
540/*
541 * release an endpoint's urbs
542 */
543static void release_urbs(struct snd_usb_endpoint *ep, int force)
544{
545 int i;
546
547 /* route incoming urbs to nirvana */
548 ep->retire_data_urb = NULL;
549 ep->prepare_data_urb = NULL;
550
551 /* stop urbs */
552 deactivate_urbs(ep, force, 1);
553 wait_clear_urbs(ep);
554
555 for (i = 0; i < ep->nurbs; i++)
556 release_urb_ctx(&ep->urb[i]);
557
558 if (ep->syncbuf)
559 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
560 ep->syncbuf, ep->sync_dma);
561
562 ep->syncbuf = NULL;
563 ep->nurbs = 0;
564}
565
566/*
567 * configure a data endpoint
568 */
569static int data_ep_set_params(struct snd_usb_endpoint *ep,
570 struct snd_pcm_hw_params *hw_params,
571 struct audioformat *fmt,
572 struct snd_usb_endpoint *sync_ep)
573{
574 unsigned int maxsize, i, urb_packs, total_packs, packs_per_ms;
575 int period_bytes = params_period_bytes(hw_params);
576 int format = params_format(hw_params);
577 int is_playback = usb_pipeout(ep->pipe);
578 int frame_bits = snd_pcm_format_physical_width(params_format(hw_params)) *
579 params_channels(hw_params);
580
581 ep->datainterval = fmt->datainterval;
582 ep->stride = frame_bits >> 3;
583 ep->silence_value = format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0;
584
585 /* calculate max. frequency */
586 if (ep->maxpacksize) {
587 /* whatever fits into a max. size packet */
588 maxsize = ep->maxpacksize;
589 ep->freqmax = (maxsize / (frame_bits >> 3))
590 << (16 - ep->datainterval);
591 } else {
592 /* no max. packet size: just take 25% higher than nominal */
593 ep->freqmax = ep->freqn + (ep->freqn >> 2);
594 maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3))
595 >> (16 - ep->datainterval);
596 }
597
598 if (ep->fill_max)
599 ep->curpacksize = ep->maxpacksize;
600 else
601 ep->curpacksize = maxsize;
602
603 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL)
604 packs_per_ms = 8 >> ep->datainterval;
605 else
606 packs_per_ms = 1;
607
608 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) {
609 urb_packs = max(ep->chip->nrpacks, 1);
610 urb_packs = min(urb_packs, (unsigned int) MAX_PACKS);
611 } else {
612 urb_packs = 1;
613 }
614
615 urb_packs *= packs_per_ms;
616
617 if (sync_ep && !snd_usb_endpoint_implict_feedback_sink(ep))
618 urb_packs = min(urb_packs, 1U << sync_ep->syncinterval);
619
620 /* decide how many packets to be used */
621 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) {
622 unsigned int minsize, maxpacks;
623 /* determine how small a packet can be */
624 minsize = (ep->freqn >> (16 - ep->datainterval))
625 * (frame_bits >> 3);
626 /* with sync from device, assume it can be 12% lower */
627 if (sync_ep)
628 minsize -= minsize >> 3;
629 minsize = max(minsize, 1u);
630 total_packs = (period_bytes + minsize - 1) / minsize;
631 /* we need at least two URBs for queueing */
632 if (total_packs < 2) {
633 total_packs = 2;
634 } else {
635 /* and we don't want too long a queue either */
636 maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
637 total_packs = min(total_packs, maxpacks);
638 }
639 } else {
640 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
641 urb_packs >>= 1;
642 total_packs = MAX_URBS * urb_packs;
643 }
644
645 ep->nurbs = (total_packs + urb_packs - 1) / urb_packs;
646 if (ep->nurbs > MAX_URBS) {
647 /* too much... */
648 ep->nurbs = MAX_URBS;
649 total_packs = MAX_URBS * urb_packs;
650 } else if (ep->nurbs < 2) {
651 /* too little - we need at least two packets
652 * to ensure contiguous playback/capture
653 */
654 ep->nurbs = 2;
655 }
656
657 /* allocate and initialize data urbs */
658 for (i = 0; i < ep->nurbs; i++) {
659 struct snd_urb_ctx *u = &ep->urb[i];
660 u->index = i;
661 u->ep = ep;
662 u->packets = (i + 1) * total_packs / ep->nurbs
663 - i * total_packs / ep->nurbs;
664 u->buffer_size = maxsize * u->packets;
665
666 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
667 u->packets++; /* for transfer delimiter */
668 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
669 if (!u->urb)
670 goto out_of_memory;
671
672 u->urb->transfer_buffer =
673 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
674 GFP_KERNEL, &u->urb->transfer_dma);
675 if (!u->urb->transfer_buffer)
676 goto out_of_memory;
677 u->urb->pipe = ep->pipe;
678 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
679 u->urb->interval = 1 << ep->datainterval;
680 u->urb->context = u;
681 u->urb->complete = snd_complete_urb;
682 INIT_LIST_HEAD(&u->ready_list);
683 }
684
685 return 0;
686
687out_of_memory:
688 release_urbs(ep, 0);
689 return -ENOMEM;
690}
691
692/*
693 * configure a sync endpoint
694 */
695static int sync_ep_set_params(struct snd_usb_endpoint *ep,
696 struct snd_pcm_hw_params *hw_params,
697 struct audioformat *fmt)
698{
699 int i;
700
701 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
702 GFP_KERNEL, &ep->sync_dma);
703 if (!ep->syncbuf)
704 return -ENOMEM;
705
706 for (i = 0; i < SYNC_URBS; i++) {
707 struct snd_urb_ctx *u = &ep->urb[i];
708 u->index = i;
709 u->ep = ep;
710 u->packets = 1;
711 u->urb = usb_alloc_urb(1, GFP_KERNEL);
712 if (!u->urb)
713 goto out_of_memory;
714 u->urb->transfer_buffer = ep->syncbuf + i * 4;
715 u->urb->transfer_dma = ep->sync_dma + i * 4;
716 u->urb->transfer_buffer_length = 4;
717 u->urb->pipe = ep->pipe;
718 u->urb->transfer_flags = URB_ISO_ASAP |
719 URB_NO_TRANSFER_DMA_MAP;
720 u->urb->number_of_packets = 1;
721 u->urb->interval = 1 << ep->syncinterval;
722 u->urb->context = u;
723 u->urb->complete = snd_complete_urb;
724 }
725
726 ep->nurbs = SYNC_URBS;
727
728 return 0;
729
730out_of_memory:
731 release_urbs(ep, 0);
732 return -ENOMEM;
733}
734
735/**
736 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
737 *
738 * @ep: the snd_usb_endpoint to configure
739 * @hw_params: the hardware parameters
740 * @fmt: the USB audio format information
741 * @sync_ep: the sync endpoint to use, if any
742 *
743 * Determine the number of URBs to be used on this endpoint.
744 * An endpoint must be configured before it can be started.
745 * An endpoint that is already running can not be reconfigured.
746 */
747int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
748 struct snd_pcm_hw_params *hw_params,
749 struct audioformat *fmt,
750 struct snd_usb_endpoint *sync_ep)
751{
752 int err;
753
754 if (ep->use_count != 0) {
755 snd_printk(KERN_WARNING "Unable to change format on ep #%x: already in use\n",
756 ep->ep_num);
757 return -EBUSY;
758 }
759
760 /* release old buffers, if any */
761 release_urbs(ep, 0);
762
763 ep->datainterval = fmt->datainterval;
764 ep->maxpacksize = fmt->maxpacksize;
765 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
766
767 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
768 ep->freqn = get_usb_full_speed_rate(params_rate(hw_params));
769 else
770 ep->freqn = get_usb_high_speed_rate(params_rate(hw_params));
771
772 /* calculate the frequency in 16.16 format */
773 ep->freqm = ep->freqn;
774 ep->freqshift = INT_MIN;
775
776 ep->phase = 0;
777
778 switch (ep->type) {
779 case SND_USB_ENDPOINT_TYPE_DATA:
780 err = data_ep_set_params(ep, hw_params, fmt, sync_ep);
781 break;
782 case SND_USB_ENDPOINT_TYPE_SYNC:
783 err = sync_ep_set_params(ep, hw_params, fmt);
784 break;
785 default:
786 err = -EINVAL;
787 }
788
789 snd_printdd(KERN_DEBUG "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
790 ep->ep_num, ep->type, ep->nurbs, err);
791
792 return err;
793}
794
795/**
796 * snd_usb_endpoint_start: start an snd_usb_endpoint
797 *
798 * @ep: the endpoint to start
799 * @can_sleep: flag indicating whether the operation is executed in
800 * non-atomic context
801 *
802 * A call to this function will increment the use count of the endpoint.
803 * In case it is not already running, the URBs for this endpoint will be
804 * submitted. Otherwise, this function does nothing.
805 *
806 * Must be balanced to calls of snd_usb_endpoint_stop().
807 *
808 * Returns an error if the URB submission failed, 0 in all other cases.
809 */
810int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep)
811{
812 int err;
813 unsigned int i;
814
815 if (ep->chip->shutdown)
816 return -EBADFD;
817
818 /* already running? */
819 if (++ep->use_count != 1)
820 return 0;
821
822 /* just to be sure */
823 deactivate_urbs(ep, 0, can_sleep);
824 if (can_sleep)
825 wait_clear_urbs(ep);
826
827 ep->active_mask = 0;
828 ep->unlink_mask = 0;
829 ep->phase = 0;
830
831 /*
832 * If this endpoint has a data endpoint as implicit feedback source,
833 * don't start the urbs here. Instead, mark them all as available,
834 * wait for the record urbs to return and queue the playback urbs
835 * from that context.
836 */
837
838 set_bit(EP_FLAG_RUNNING, &ep->flags);
839
840 if (snd_usb_endpoint_implict_feedback_sink(ep)) {
841 for (i = 0; i < ep->nurbs; i++) {
842 struct snd_urb_ctx *ctx = ep->urb + i;
843 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
844 }
845
846 return 0;
847 }
848
849 for (i = 0; i < ep->nurbs; i++) {
850 struct urb *urb = ep->urb[i].urb;
851
852 if (snd_BUG_ON(!urb))
853 goto __error;
854
855 if (usb_pipeout(ep->pipe)) {
856 prepare_outbound_urb(ep, urb->context);
857 } else {
858 prepare_inbound_urb(ep, urb->context);
859 }
860
861 err = usb_submit_urb(urb, GFP_ATOMIC);
862 if (err < 0) {
863 snd_printk(KERN_ERR "cannot submit urb %d, error %d: %s\n",
864 i, err, usb_error_string(err));
865 goto __error;
866 }
867 set_bit(i, &ep->active_mask);
868 }
869
870 return 0;
871
872__error:
873 clear_bit(EP_FLAG_RUNNING, &ep->flags);
874 ep->use_count--;
875 deactivate_urbs(ep, 0, 0);
876 return -EPIPE;
877}
878
879/**
880 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
881 *
882 * @ep: the endpoint to stop (may be NULL)
883 *
884 * A call to this function will decrement the use count of the endpoint.
885 * In case the last user has requested the endpoint stop, the URBs will
886 * actually be deactivated.
887 *
888 * Must be balanced to calls of snd_usb_endpoint_start().
889 */
890void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep,
891 int force, int can_sleep, int wait)
892{
893 if (!ep)
894 return;
895
896 if (snd_BUG_ON(ep->use_count == 0))
897 return;
898
899 if (--ep->use_count == 0) {
900 deactivate_urbs(ep, force, can_sleep);
901 ep->data_subs = NULL;
902 ep->sync_slave = NULL;
903 ep->retire_data_urb = NULL;
904 ep->prepare_data_urb = NULL;
905
906 if (wait)
907 wait_clear_urbs(ep);
908 }
909}
910
911/**
912 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
913 *
914 * @ep: the endpoint to deactivate
915 *
916 * If the endpoint is not currently in use, this functions will select the
917 * alternate interface setting 0 for the interface of this endpoint.
918 *
919 * In case of any active users, this functions does nothing.
920 *
921 * Returns an error if usb_set_interface() failed, 0 in all other
922 * cases.
923 */
924int snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
925{
926 if (!ep)
927 return -EINVAL;
928
929 deactivate_urbs(ep, 1, 1);
930 wait_clear_urbs(ep);
931
932 if (ep->use_count != 0)
933 return 0;
934
935 clear_bit(EP_FLAG_ACTIVATED, &ep->flags);
936
937 return 0;
938}
939
940/**
941 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
942 *
943 * @ep: the list header of the endpoint to free
944 *
945 * This function does not care for the endpoint's use count but will tear
946 * down all the streaming URBs immediately and free all resources.
947 */
948void snd_usb_endpoint_free(struct list_head *head)
949{
950 struct snd_usb_endpoint *ep;
951
952 ep = list_entry(head, struct snd_usb_endpoint, list);
953 release_urbs(ep, 1);
954 kfree(ep);
955}
956
957/**
958 * snd_usb_handle_sync_urb: parse an USB sync packet
959 *
960 * @ep: the endpoint to handle the packet
961 * @sender: the sending endpoint
962 * @urb: the received packet
963 *
964 * This function is called from the context of an endpoint that received
965 * the packet and is used to let another endpoint object handle the payload.
966 */
967void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
968 struct snd_usb_endpoint *sender,
969 const struct urb *urb)
970{
971 int shift;
972 unsigned int f;
973 unsigned long flags;
974
975 snd_BUG_ON(ep == sender);
976
977 /*
978 * In case the endpoint is operating in implicit feedback mode, prepare
979 * a new outbound URB that has the same layout as the received packet
980 * and add it to the list of pending urbs. queue_pending_output_urbs()
981 * will take care of them later.
982 */
983 if (snd_usb_endpoint_implict_feedback_sink(ep) &&
984 ep->use_count != 0) {
985
986 /* implicit feedback case */
987 int i, bytes = 0;
988 struct snd_urb_ctx *in_ctx;
989 struct snd_usb_packet_info *out_packet;
990
991 in_ctx = urb->context;
992
993 /* Count overall packet size */
994 for (i = 0; i < in_ctx->packets; i++)
995 if (urb->iso_frame_desc[i].status == 0)
996 bytes += urb->iso_frame_desc[i].actual_length;
997
998 /*
999 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1000 * streaming once it received a 0-byte OUT URB
1001 */
1002 if (bytes == 0)
1003 return;
1004
1005 spin_lock_irqsave(&ep->lock, flags);
1006 out_packet = ep->next_packet + ep->next_packet_write_pos;
1007
1008 /*
1009 * Iterate through the inbound packet and prepare the lengths
1010 * for the output packet. The OUT packet we are about to send
1011 * will have the same amount of payload bytes than the IN
1012 * packet we just received.
1013 */
1014
1015 out_packet->packets = in_ctx->packets;
1016 for (i = 0; i < in_ctx->packets; i++) {
1017 if (urb->iso_frame_desc[i].status == 0)
1018 out_packet->packet_size[i] =
1019 urb->iso_frame_desc[i].actual_length / ep->stride;
1020 else
1021 out_packet->packet_size[i] = 0;
1022 }
1023
1024 ep->next_packet_write_pos++;
1025 ep->next_packet_write_pos %= MAX_URBS;
1026 spin_unlock_irqrestore(&ep->lock, flags);
1027 queue_pending_output_urbs(ep);
1028
1029 return;
1030 }
1031
1032 /*
1033 * process after playback sync complete
1034 *
1035 * Full speed devices report feedback values in 10.14 format as samples
1036 * per frame, high speed devices in 16.16 format as samples per
1037 * microframe.
1038 *
1039 * Because the Audio Class 1 spec was written before USB 2.0, many high
1040 * speed devices use a wrong interpretation, some others use an
1041 * entirely different format.
1042 *
1043 * Therefore, we cannot predict what format any particular device uses
1044 * and must detect it automatically.
1045 */
1046
1047 if (urb->iso_frame_desc[0].status != 0 ||
1048 urb->iso_frame_desc[0].actual_length < 3)
1049 return;
1050
1051 f = le32_to_cpup(urb->transfer_buffer);
1052 if (urb->iso_frame_desc[0].actual_length == 3)
1053 f &= 0x00ffffff;
1054 else
1055 f &= 0x0fffffff;
1056
1057 if (f == 0)
1058 return;
1059
1060 if (unlikely(ep->freqshift == INT_MIN)) {
1061 /*
1062 * The first time we see a feedback value, determine its format
1063 * by shifting it left or right until it matches the nominal
1064 * frequency value. This assumes that the feedback does not
1065 * differ from the nominal value more than +50% or -25%.
1066 */
1067 shift = 0;
1068 while (f < ep->freqn - ep->freqn / 4) {
1069 f <<= 1;
1070 shift++;
1071 }
1072 while (f > ep->freqn + ep->freqn / 2) {
1073 f >>= 1;
1074 shift--;
1075 }
1076 ep->freqshift = shift;
1077 } else if (ep->freqshift >= 0)
1078 f <<= ep->freqshift;
1079 else
1080 f >>= -ep->freqshift;
1081
1082 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1083 /*
1084 * If the frequency looks valid, set it.
1085 * This value is referred to in prepare_playback_urb().
1086 */
1087 spin_lock_irqsave(&ep->lock, flags);
1088 ep->freqm = f;
1089 spin_unlock_irqrestore(&ep->lock, flags);
1090 } else {
1091 /*
1092 * Out of range; maybe the shift value is wrong.
1093 * Reset it so that we autodetect again the next time.
1094 */
1095 ep->freqshift = INT_MIN;
1096 }
1097}
1098