Commit | Line | Data |
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e5779998 DM |
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 | ||
c731bc96 DM |
18 | #include <linux/gfp.h> |
19 | #include <linux/init.h> | |
80c8a2a3 | 20 | #include <linux/ratelimit.h> |
c731bc96 DM |
21 | #include <linux/usb.h> |
22 | #include <linux/usb/audio.h> | |
8fdff6a3 | 23 | #include <linux/slab.h> |
c731bc96 DM |
24 | |
25 | #include <sound/core.h> | |
26 | #include <sound/pcm.h> | |
8fdff6a3 | 27 | #include <sound/pcm_params.h> |
c731bc96 DM |
28 | |
29 | #include "usbaudio.h" | |
30 | #include "helper.h" | |
31 | #include "card.h" | |
32 | #include "endpoint.h" | |
33 | #include "pcm.h" | |
2b58fd5b | 34 | #include "quirks.h" |
c731bc96 | 35 | |
8fdff6a3 DM |
36 | #define EP_FLAG_ACTIVATED 0 |
37 | #define EP_FLAG_RUNNING 1 | |
f58161ba | 38 | #define EP_FLAG_STOPPING 2 |
8fdff6a3 | 39 | |
94c27215 DM |
40 | /* |
41 | * snd_usb_endpoint is a model that abstracts everything related to an | |
42 | * USB endpoint and its streaming. | |
43 | * | |
44 | * There are functions to activate and deactivate the streaming URBs and | |
07a5e9d4 | 45 | * optional callbacks to let the pcm logic handle the actual content of the |
94c27215 DM |
46 | * packets for playback and record. Thus, the bus streaming and the audio |
47 | * handlers are fully decoupled. | |
48 | * | |
07a5e9d4 | 49 | * There are two different types of endpoints in audio applications. |
94c27215 DM |
50 | * |
51 | * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both | |
52 | * inbound and outbound traffic. | |
53 | * | |
07a5e9d4 DM |
54 | * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and |
55 | * expect the payload to carry Q10.14 / Q16.16 formatted sync information | |
56 | * (3 or 4 bytes). | |
94c27215 | 57 | * |
07a5e9d4 DM |
58 | * Each endpoint has to be configured prior to being used by calling |
59 | * snd_usb_endpoint_set_params(). | |
94c27215 DM |
60 | * |
61 | * The model incorporates a reference counting, so that multiple users | |
62 | * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and | |
63 | * only the first user will effectively start the URBs, and only the last | |
07a5e9d4 | 64 | * one to stop it will tear the URBs down again. |
94c27215 DM |
65 | */ |
66 | ||
c731bc96 DM |
67 | /* |
68 | * convert a sampling rate into our full speed format (fs/1000 in Q16.16) | |
69 | * this will overflow at approx 524 kHz | |
70 | */ | |
71 | static inline unsigned get_usb_full_speed_rate(unsigned int rate) | |
72 | { | |
73 | return ((rate << 13) + 62) / 125; | |
74 | } | |
75 | ||
76 | /* | |
77 | * convert a sampling rate into USB high speed format (fs/8000 in Q16.16) | |
78 | * this will overflow at approx 4 MHz | |
79 | */ | |
80 | static inline unsigned get_usb_high_speed_rate(unsigned int rate) | |
81 | { | |
82 | return ((rate << 10) + 62) / 125; | |
83 | } | |
84 | ||
c731bc96 DM |
85 | /* |
86 | * release a urb data | |
87 | */ | |
88 | static void release_urb_ctx(struct snd_urb_ctx *u) | |
89 | { | |
d399ff95 DM |
90 | if (u->buffer_size) |
91 | usb_free_coherent(u->ep->chip->dev, u->buffer_size, | |
92 | u->urb->transfer_buffer, | |
93 | u->urb->transfer_dma); | |
94 | usb_free_urb(u->urb); | |
95 | u->urb = NULL; | |
c731bc96 DM |
96 | } |
97 | ||
98 | static const char *usb_error_string(int err) | |
99 | { | |
100 | switch (err) { | |
101 | case -ENODEV: | |
102 | return "no device"; | |
103 | case -ENOENT: | |
104 | return "endpoint not enabled"; | |
105 | case -EPIPE: | |
106 | return "endpoint stalled"; | |
107 | case -ENOSPC: | |
108 | return "not enough bandwidth"; | |
109 | case -ESHUTDOWN: | |
110 | return "device disabled"; | |
111 | case -EHOSTUNREACH: | |
112 | return "device suspended"; | |
113 | case -EINVAL: | |
114 | case -EAGAIN: | |
115 | case -EFBIG: | |
116 | case -EMSGSIZE: | |
117 | return "internal error"; | |
118 | default: | |
119 | return "unknown error"; | |
120 | } | |
121 | } | |
122 | ||
94c27215 DM |
123 | /** |
124 | * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type | |
125 | * | |
07a5e9d4 | 126 | * @ep: The snd_usb_endpoint |
94c27215 DM |
127 | * |
128 | * Determine whether an endpoint is driven by an implicit feedback | |
129 | * data endpoint source. | |
130 | */ | |
8fdff6a3 DM |
131 | int snd_usb_endpoint_implict_feedback_sink(struct snd_usb_endpoint *ep) |
132 | { | |
133 | return ep->sync_master && | |
134 | ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA && | |
135 | ep->type == SND_USB_ENDPOINT_TYPE_DATA && | |
136 | usb_pipeout(ep->pipe); | |
137 | } | |
138 | ||
94c27215 DM |
139 | /* |
140 | * For streaming based on information derived from sync endpoints, | |
141 | * prepare_outbound_urb_sizes() will call next_packet_size() to | |
142 | * determine the number of samples to be sent in the next packet. | |
143 | * | |
144 | * For implicit feedback, next_packet_size() is unused. | |
145 | */ | |
245baf98 | 146 | int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep) |
8fdff6a3 DM |
147 | { |
148 | unsigned long flags; | |
149 | int ret; | |
150 | ||
151 | if (ep->fill_max) | |
152 | return ep->maxframesize; | |
153 | ||
154 | spin_lock_irqsave(&ep->lock, flags); | |
155 | ep->phase = (ep->phase & 0xffff) | |
156 | + (ep->freqm << ep->datainterval); | |
157 | ret = min(ep->phase >> 16, ep->maxframesize); | |
158 | spin_unlock_irqrestore(&ep->lock, flags); | |
159 | ||
160 | return ret; | |
161 | } | |
162 | ||
163 | static void retire_outbound_urb(struct snd_usb_endpoint *ep, | |
164 | struct snd_urb_ctx *urb_ctx) | |
165 | { | |
166 | if (ep->retire_data_urb) | |
167 | ep->retire_data_urb(ep->data_subs, urb_ctx->urb); | |
168 | } | |
169 | ||
170 | static void retire_inbound_urb(struct snd_usb_endpoint *ep, | |
171 | struct snd_urb_ctx *urb_ctx) | |
172 | { | |
173 | struct urb *urb = urb_ctx->urb; | |
174 | ||
2b58fd5b DM |
175 | if (unlikely(ep->skip_packets > 0)) { |
176 | ep->skip_packets--; | |
177 | return; | |
178 | } | |
179 | ||
8fdff6a3 DM |
180 | if (ep->sync_slave) |
181 | snd_usb_handle_sync_urb(ep->sync_slave, ep, urb); | |
182 | ||
183 | if (ep->retire_data_urb) | |
184 | ep->retire_data_urb(ep->data_subs, urb); | |
185 | } | |
186 | ||
8fdff6a3 DM |
187 | /* |
188 | * Prepare a PLAYBACK urb for submission to the bus. | |
189 | */ | |
190 | static void prepare_outbound_urb(struct snd_usb_endpoint *ep, | |
191 | struct snd_urb_ctx *ctx) | |
192 | { | |
193 | int i; | |
194 | struct urb *urb = ctx->urb; | |
195 | unsigned char *cp = urb->transfer_buffer; | |
196 | ||
197 | urb->dev = ep->chip->dev; /* we need to set this at each time */ | |
198 | ||
199 | switch (ep->type) { | |
200 | case SND_USB_ENDPOINT_TYPE_DATA: | |
201 | if (ep->prepare_data_urb) { | |
202 | ep->prepare_data_urb(ep->data_subs, urb); | |
203 | } else { | |
204 | /* no data provider, so send silence */ | |
205 | unsigned int offs = 0; | |
206 | for (i = 0; i < ctx->packets; ++i) { | |
8dce30c8 DM |
207 | int counts; |
208 | ||
209 | if (ctx->packet_size[i]) | |
210 | counts = ctx->packet_size[i]; | |
211 | else | |
212 | counts = snd_usb_endpoint_next_packet_size(ep); | |
213 | ||
8fdff6a3 DM |
214 | urb->iso_frame_desc[i].offset = offs * ep->stride; |
215 | urb->iso_frame_desc[i].length = counts * ep->stride; | |
216 | offs += counts; | |
217 | } | |
218 | ||
219 | urb->number_of_packets = ctx->packets; | |
220 | urb->transfer_buffer_length = offs * ep->stride; | |
221 | memset(urb->transfer_buffer, ep->silence_value, | |
222 | offs * ep->stride); | |
223 | } | |
224 | break; | |
225 | ||
226 | case SND_USB_ENDPOINT_TYPE_SYNC: | |
227 | if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) { | |
228 | /* | |
229 | * fill the length and offset of each urb descriptor. | |
230 | * the fixed 12.13 frequency is passed as 16.16 through the pipe. | |
231 | */ | |
232 | urb->iso_frame_desc[0].length = 4; | |
233 | urb->iso_frame_desc[0].offset = 0; | |
234 | cp[0] = ep->freqn; | |
235 | cp[1] = ep->freqn >> 8; | |
236 | cp[2] = ep->freqn >> 16; | |
237 | cp[3] = ep->freqn >> 24; | |
238 | } else { | |
239 | /* | |
240 | * fill the length and offset of each urb descriptor. | |
241 | * the fixed 10.14 frequency is passed through the pipe. | |
242 | */ | |
243 | urb->iso_frame_desc[0].length = 3; | |
244 | urb->iso_frame_desc[0].offset = 0; | |
245 | cp[0] = ep->freqn >> 2; | |
246 | cp[1] = ep->freqn >> 10; | |
247 | cp[2] = ep->freqn >> 18; | |
248 | } | |
249 | ||
250 | break; | |
251 | } | |
252 | } | |
253 | ||
254 | /* | |
255 | * Prepare a CAPTURE or SYNC urb for submission to the bus. | |
256 | */ | |
257 | static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep, | |
258 | struct snd_urb_ctx *urb_ctx) | |
259 | { | |
260 | int i, offs; | |
261 | struct urb *urb = urb_ctx->urb; | |
262 | ||
263 | urb->dev = ep->chip->dev; /* we need to set this at each time */ | |
264 | ||
265 | switch (ep->type) { | |
266 | case SND_USB_ENDPOINT_TYPE_DATA: | |
267 | offs = 0; | |
268 | for (i = 0; i < urb_ctx->packets; i++) { | |
269 | urb->iso_frame_desc[i].offset = offs; | |
270 | urb->iso_frame_desc[i].length = ep->curpacksize; | |
271 | offs += ep->curpacksize; | |
272 | } | |
273 | ||
274 | urb->transfer_buffer_length = offs; | |
275 | urb->number_of_packets = urb_ctx->packets; | |
276 | break; | |
277 | ||
278 | case SND_USB_ENDPOINT_TYPE_SYNC: | |
279 | urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize); | |
280 | urb->iso_frame_desc[0].offset = 0; | |
281 | break; | |
282 | } | |
283 | } | |
284 | ||
94c27215 | 285 | /* |
07a5e9d4 | 286 | * Send output urbs that have been prepared previously. URBs are dequeued |
94c27215 DM |
287 | * from ep->ready_playback_urbs and in case there there aren't any available |
288 | * or there are no packets that have been prepared, this function does | |
289 | * nothing. | |
290 | * | |
07a5e9d4 DM |
291 | * The reason why the functionality of sending and preparing URBs is separated |
292 | * is that host controllers don't guarantee the order in which they return | |
293 | * inbound and outbound packets to their submitters. | |
94c27215 DM |
294 | * |
295 | * This function is only used for implicit feedback endpoints. For endpoints | |
07a5e9d4 DM |
296 | * driven by dedicated sync endpoints, URBs are immediately re-submitted |
297 | * from their completion handler. | |
94c27215 | 298 | */ |
8fdff6a3 DM |
299 | static void queue_pending_output_urbs(struct snd_usb_endpoint *ep) |
300 | { | |
301 | while (test_bit(EP_FLAG_RUNNING, &ep->flags)) { | |
302 | ||
303 | unsigned long flags; | |
68853fa3 | 304 | struct snd_usb_packet_info *uninitialized_var(packet); |
8fdff6a3 DM |
305 | struct snd_urb_ctx *ctx = NULL; |
306 | struct urb *urb; | |
307 | int err, i; | |
308 | ||
309 | spin_lock_irqsave(&ep->lock, flags); | |
310 | if (ep->next_packet_read_pos != ep->next_packet_write_pos) { | |
311 | packet = ep->next_packet + ep->next_packet_read_pos; | |
312 | ep->next_packet_read_pos++; | |
313 | ep->next_packet_read_pos %= MAX_URBS; | |
314 | ||
315 | /* take URB out of FIFO */ | |
316 | if (!list_empty(&ep->ready_playback_urbs)) | |
317 | ctx = list_first_entry(&ep->ready_playback_urbs, | |
318 | struct snd_urb_ctx, ready_list); | |
319 | } | |
320 | spin_unlock_irqrestore(&ep->lock, flags); | |
321 | ||
322 | if (ctx == NULL) | |
323 | return; | |
324 | ||
325 | list_del_init(&ctx->ready_list); | |
326 | urb = ctx->urb; | |
327 | ||
328 | /* copy over the length information */ | |
329 | for (i = 0; i < packet->packets; i++) | |
330 | ctx->packet_size[i] = packet->packet_size[i]; | |
331 | ||
94c27215 | 332 | /* call the data handler to fill in playback data */ |
8fdff6a3 DM |
333 | prepare_outbound_urb(ep, ctx); |
334 | ||
335 | err = usb_submit_urb(ctx->urb, GFP_ATOMIC); | |
336 | if (err < 0) | |
337 | snd_printk(KERN_ERR "Unable to submit urb #%d: %d (urb %p)\n", | |
338 | ctx->index, err, ctx->urb); | |
339 | else | |
340 | set_bit(ctx->index, &ep->active_mask); | |
341 | } | |
342 | } | |
343 | ||
344 | /* | |
345 | * complete callback for urbs | |
346 | */ | |
347 | static void snd_complete_urb(struct urb *urb) | |
348 | { | |
349 | struct snd_urb_ctx *ctx = urb->context; | |
350 | struct snd_usb_endpoint *ep = ctx->ep; | |
351 | int err; | |
352 | ||
353 | if (unlikely(urb->status == -ENOENT || /* unlinked */ | |
354 | urb->status == -ENODEV || /* device removed */ | |
355 | urb->status == -ECONNRESET || /* unlinked */ | |
356 | urb->status == -ESHUTDOWN || /* device disabled */ | |
357 | ep->chip->shutdown)) /* device disconnected */ | |
358 | goto exit_clear; | |
359 | ||
360 | if (usb_pipeout(ep->pipe)) { | |
361 | retire_outbound_urb(ep, ctx); | |
362 | /* can be stopped during retire callback */ | |
363 | if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) | |
364 | goto exit_clear; | |
365 | ||
366 | if (snd_usb_endpoint_implict_feedback_sink(ep)) { | |
367 | unsigned long flags; | |
368 | ||
369 | spin_lock_irqsave(&ep->lock, flags); | |
370 | list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); | |
371 | spin_unlock_irqrestore(&ep->lock, flags); | |
372 | queue_pending_output_urbs(ep); | |
373 | ||
374 | goto exit_clear; | |
375 | } | |
376 | ||
8fdff6a3 DM |
377 | prepare_outbound_urb(ep, ctx); |
378 | } else { | |
379 | retire_inbound_urb(ep, ctx); | |
380 | /* can be stopped during retire callback */ | |
381 | if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) | |
382 | goto exit_clear; | |
383 | ||
384 | prepare_inbound_urb(ep, ctx); | |
385 | } | |
386 | ||
387 | err = usb_submit_urb(urb, GFP_ATOMIC); | |
388 | if (err == 0) | |
389 | return; | |
390 | ||
391 | snd_printk(KERN_ERR "cannot submit urb (err = %d)\n", err); | |
392 | //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN); | |
393 | ||
394 | exit_clear: | |
395 | clear_bit(ctx->index, &ep->active_mask); | |
396 | } | |
397 | ||
94c27215 | 398 | /** |
07a5e9d4 | 399 | * snd_usb_add_endpoint: Add an endpoint to an USB audio chip |
94c27215 DM |
400 | * |
401 | * @chip: The chip | |
402 | * @alts: The USB host interface | |
403 | * @ep_num: The number of the endpoint to use | |
404 | * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE | |
405 | * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC | |
406 | * | |
407 | * If the requested endpoint has not been added to the given chip before, | |
408 | * a new instance is created. Otherwise, a pointer to the previoulsy | |
409 | * created instance is returned. In case of any error, NULL is returned. | |
410 | * | |
411 | * New endpoints will be added to chip->ep_list and must be freed by | |
412 | * calling snd_usb_endpoint_free(). | |
413 | */ | |
8fdff6a3 DM |
414 | struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip, |
415 | struct usb_host_interface *alts, | |
416 | int ep_num, int direction, int type) | |
417 | { | |
418 | struct list_head *p; | |
419 | struct snd_usb_endpoint *ep; | |
68e67f40 | 420 | int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK; |
8fdff6a3 DM |
421 | |
422 | mutex_lock(&chip->mutex); | |
423 | ||
424 | list_for_each(p, &chip->ep_list) { | |
425 | ep = list_entry(p, struct snd_usb_endpoint, list); | |
426 | if (ep->ep_num == ep_num && | |
427 | ep->iface == alts->desc.bInterfaceNumber && | |
428 | ep->alt_idx == alts->desc.bAlternateSetting) { | |
429 | snd_printdd(KERN_DEBUG "Re-using EP %x in iface %d,%d @%p\n", | |
430 | ep_num, ep->iface, ep->alt_idx, ep); | |
431 | goto __exit_unlock; | |
432 | } | |
433 | } | |
434 | ||
435 | snd_printdd(KERN_DEBUG "Creating new %s %s endpoint #%x\n", | |
436 | is_playback ? "playback" : "capture", | |
437 | type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync", | |
438 | ep_num); | |
439 | ||
8fdff6a3 DM |
440 | ep = kzalloc(sizeof(*ep), GFP_KERNEL); |
441 | if (!ep) | |
442 | goto __exit_unlock; | |
443 | ||
444 | ep->chip = chip; | |
445 | spin_lock_init(&ep->lock); | |
446 | ep->type = type; | |
447 | ep->ep_num = ep_num; | |
448 | ep->iface = alts->desc.bInterfaceNumber; | |
449 | ep->alt_idx = alts->desc.bAlternateSetting; | |
450 | INIT_LIST_HEAD(&ep->ready_playback_urbs); | |
451 | ep_num &= USB_ENDPOINT_NUMBER_MASK; | |
452 | ||
453 | if (is_playback) | |
454 | ep->pipe = usb_sndisocpipe(chip->dev, ep_num); | |
455 | else | |
456 | ep->pipe = usb_rcvisocpipe(chip->dev, ep_num); | |
457 | ||
458 | if (type == SND_USB_ENDPOINT_TYPE_SYNC) { | |
459 | if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE && | |
460 | get_endpoint(alts, 1)->bRefresh >= 1 && | |
461 | get_endpoint(alts, 1)->bRefresh <= 9) | |
462 | ep->syncinterval = get_endpoint(alts, 1)->bRefresh; | |
463 | else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) | |
464 | ep->syncinterval = 1; | |
465 | else if (get_endpoint(alts, 1)->bInterval >= 1 && | |
466 | get_endpoint(alts, 1)->bInterval <= 16) | |
467 | ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1; | |
468 | else | |
469 | ep->syncinterval = 3; | |
470 | ||
471 | ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize); | |
472 | } | |
473 | ||
474 | list_add_tail(&ep->list, &chip->ep_list); | |
475 | ||
476 | __exit_unlock: | |
477 | mutex_unlock(&chip->mutex); | |
478 | ||
479 | return ep; | |
480 | } | |
481 | ||
482 | /* | |
483 | * wait until all urbs are processed. | |
484 | */ | |
485 | static int wait_clear_urbs(struct snd_usb_endpoint *ep) | |
486 | { | |
487 | unsigned long end_time = jiffies + msecs_to_jiffies(1000); | |
488 | unsigned int i; | |
489 | int alive; | |
490 | ||
491 | do { | |
492 | alive = 0; | |
493 | for (i = 0; i < ep->nurbs; i++) | |
494 | if (test_bit(i, &ep->active_mask)) | |
495 | alive++; | |
496 | ||
497 | if (!alive) | |
498 | break; | |
499 | ||
500 | schedule_timeout_uninterruptible(1); | |
501 | } while (time_before(jiffies, end_time)); | |
502 | ||
503 | if (alive) | |
504 | snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n", | |
505 | alive, ep->ep_num); | |
f58161ba | 506 | clear_bit(EP_FLAG_STOPPING, &ep->flags); |
8fdff6a3 DM |
507 | |
508 | return 0; | |
509 | } | |
510 | ||
f58161ba TI |
511 | /* sync the pending stop operation; |
512 | * this function itself doesn't trigger the stop operation | |
513 | */ | |
514 | void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep) | |
515 | { | |
516 | if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags)) | |
517 | wait_clear_urbs(ep); | |
518 | } | |
519 | ||
8fdff6a3 DM |
520 | /* |
521 | * unlink active urbs. | |
522 | */ | |
523 | static int deactivate_urbs(struct snd_usb_endpoint *ep, int force, int can_sleep) | |
524 | { | |
8fdff6a3 DM |
525 | unsigned int i; |
526 | int async; | |
527 | ||
528 | if (!force && ep->chip->shutdown) /* to be sure... */ | |
529 | return -EBADFD; | |
530 | ||
531 | async = !can_sleep && ep->chip->async_unlink; | |
532 | ||
533 | clear_bit(EP_FLAG_RUNNING, &ep->flags); | |
534 | ||
535 | INIT_LIST_HEAD(&ep->ready_playback_urbs); | |
536 | ep->next_packet_read_pos = 0; | |
537 | ep->next_packet_write_pos = 0; | |
538 | ||
539 | if (!async && in_interrupt()) | |
540 | return 0; | |
541 | ||
542 | for (i = 0; i < ep->nurbs; i++) { | |
543 | if (test_bit(i, &ep->active_mask)) { | |
544 | if (!test_and_set_bit(i, &ep->unlink_mask)) { | |
545 | struct urb *u = ep->urb[i].urb; | |
546 | if (async) | |
547 | usb_unlink_urb(u); | |
548 | else | |
549 | usb_kill_urb(u); | |
550 | } | |
551 | } | |
552 | } | |
553 | ||
554 | return 0; | |
555 | } | |
556 | ||
557 | /* | |
558 | * release an endpoint's urbs | |
559 | */ | |
560 | static void release_urbs(struct snd_usb_endpoint *ep, int force) | |
561 | { | |
562 | int i; | |
563 | ||
564 | /* route incoming urbs to nirvana */ | |
565 | ep->retire_data_urb = NULL; | |
566 | ep->prepare_data_urb = NULL; | |
567 | ||
568 | /* stop urbs */ | |
569 | deactivate_urbs(ep, force, 1); | |
570 | wait_clear_urbs(ep); | |
571 | ||
572 | for (i = 0; i < ep->nurbs; i++) | |
573 | release_urb_ctx(&ep->urb[i]); | |
574 | ||
575 | if (ep->syncbuf) | |
576 | usb_free_coherent(ep->chip->dev, SYNC_URBS * 4, | |
577 | ep->syncbuf, ep->sync_dma); | |
578 | ||
579 | ep->syncbuf = NULL; | |
580 | ep->nurbs = 0; | |
581 | } | |
582 | ||
94c27215 DM |
583 | /* |
584 | * configure a data endpoint | |
585 | */ | |
8fdff6a3 | 586 | static int data_ep_set_params(struct snd_usb_endpoint *ep, |
35ec7aa2 DR |
587 | snd_pcm_format_t pcm_format, |
588 | unsigned int channels, | |
589 | unsigned int period_bytes, | |
8fdff6a3 DM |
590 | struct audioformat *fmt, |
591 | struct snd_usb_endpoint *sync_ep) | |
592 | { | |
593 | unsigned int maxsize, i, urb_packs, total_packs, packs_per_ms; | |
8fdff6a3 | 594 | int is_playback = usb_pipeout(ep->pipe); |
35ec7aa2 | 595 | int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels; |
8fdff6a3 DM |
596 | |
597 | ep->datainterval = fmt->datainterval; | |
598 | ep->stride = frame_bits >> 3; | |
35ec7aa2 | 599 | ep->silence_value = pcm_format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0; |
8fdff6a3 DM |
600 | |
601 | /* calculate max. frequency */ | |
602 | if (ep->maxpacksize) { | |
603 | /* whatever fits into a max. size packet */ | |
604 | maxsize = ep->maxpacksize; | |
605 | ep->freqmax = (maxsize / (frame_bits >> 3)) | |
606 | << (16 - ep->datainterval); | |
607 | } else { | |
608 | /* no max. packet size: just take 25% higher than nominal */ | |
609 | ep->freqmax = ep->freqn + (ep->freqn >> 2); | |
610 | maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3)) | |
611 | >> (16 - ep->datainterval); | |
612 | } | |
613 | ||
614 | if (ep->fill_max) | |
615 | ep->curpacksize = ep->maxpacksize; | |
616 | else | |
617 | ep->curpacksize = maxsize; | |
618 | ||
619 | if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) | |
620 | packs_per_ms = 8 >> ep->datainterval; | |
621 | else | |
622 | packs_per_ms = 1; | |
623 | ||
624 | if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { | |
625 | urb_packs = max(ep->chip->nrpacks, 1); | |
626 | urb_packs = min(urb_packs, (unsigned int) MAX_PACKS); | |
627 | } else { | |
628 | urb_packs = 1; | |
629 | } | |
630 | ||
631 | urb_packs *= packs_per_ms; | |
632 | ||
633 | if (sync_ep && !snd_usb_endpoint_implict_feedback_sink(ep)) | |
634 | urb_packs = min(urb_packs, 1U << sync_ep->syncinterval); | |
635 | ||
636 | /* decide how many packets to be used */ | |
637 | if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { | |
638 | unsigned int minsize, maxpacks; | |
639 | /* determine how small a packet can be */ | |
640 | minsize = (ep->freqn >> (16 - ep->datainterval)) | |
641 | * (frame_bits >> 3); | |
642 | /* with sync from device, assume it can be 12% lower */ | |
643 | if (sync_ep) | |
644 | minsize -= minsize >> 3; | |
645 | minsize = max(minsize, 1u); | |
646 | total_packs = (period_bytes + minsize - 1) / minsize; | |
647 | /* we need at least two URBs for queueing */ | |
648 | if (total_packs < 2) { | |
649 | total_packs = 2; | |
650 | } else { | |
651 | /* and we don't want too long a queue either */ | |
652 | maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2); | |
653 | total_packs = min(total_packs, maxpacks); | |
654 | } | |
655 | } else { | |
656 | while (urb_packs > 1 && urb_packs * maxsize >= period_bytes) | |
657 | urb_packs >>= 1; | |
658 | total_packs = MAX_URBS * urb_packs; | |
659 | } | |
660 | ||
661 | ep->nurbs = (total_packs + urb_packs - 1) / urb_packs; | |
662 | if (ep->nurbs > MAX_URBS) { | |
663 | /* too much... */ | |
664 | ep->nurbs = MAX_URBS; | |
665 | total_packs = MAX_URBS * urb_packs; | |
666 | } else if (ep->nurbs < 2) { | |
667 | /* too little - we need at least two packets | |
668 | * to ensure contiguous playback/capture | |
669 | */ | |
670 | ep->nurbs = 2; | |
671 | } | |
672 | ||
673 | /* allocate and initialize data urbs */ | |
674 | for (i = 0; i < ep->nurbs; i++) { | |
675 | struct snd_urb_ctx *u = &ep->urb[i]; | |
676 | u->index = i; | |
677 | u->ep = ep; | |
678 | u->packets = (i + 1) * total_packs / ep->nurbs | |
679 | - i * total_packs / ep->nurbs; | |
680 | u->buffer_size = maxsize * u->packets; | |
681 | ||
682 | if (fmt->fmt_type == UAC_FORMAT_TYPE_II) | |
683 | u->packets++; /* for transfer delimiter */ | |
684 | u->urb = usb_alloc_urb(u->packets, GFP_KERNEL); | |
685 | if (!u->urb) | |
686 | goto out_of_memory; | |
687 | ||
688 | u->urb->transfer_buffer = | |
689 | usb_alloc_coherent(ep->chip->dev, u->buffer_size, | |
690 | GFP_KERNEL, &u->urb->transfer_dma); | |
691 | if (!u->urb->transfer_buffer) | |
692 | goto out_of_memory; | |
693 | u->urb->pipe = ep->pipe; | |
694 | u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; | |
695 | u->urb->interval = 1 << ep->datainterval; | |
696 | u->urb->context = u; | |
697 | u->urb->complete = snd_complete_urb; | |
698 | INIT_LIST_HEAD(&u->ready_list); | |
699 | } | |
700 | ||
701 | return 0; | |
702 | ||
703 | out_of_memory: | |
704 | release_urbs(ep, 0); | |
705 | return -ENOMEM; | |
706 | } | |
707 | ||
94c27215 DM |
708 | /* |
709 | * configure a sync endpoint | |
710 | */ | |
8fdff6a3 | 711 | static int sync_ep_set_params(struct snd_usb_endpoint *ep, |
8fdff6a3 DM |
712 | struct audioformat *fmt) |
713 | { | |
714 | int i; | |
715 | ||
716 | ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4, | |
717 | GFP_KERNEL, &ep->sync_dma); | |
718 | if (!ep->syncbuf) | |
719 | return -ENOMEM; | |
720 | ||
721 | for (i = 0; i < SYNC_URBS; i++) { | |
722 | struct snd_urb_ctx *u = &ep->urb[i]; | |
723 | u->index = i; | |
724 | u->ep = ep; | |
725 | u->packets = 1; | |
726 | u->urb = usb_alloc_urb(1, GFP_KERNEL); | |
727 | if (!u->urb) | |
728 | goto out_of_memory; | |
729 | u->urb->transfer_buffer = ep->syncbuf + i * 4; | |
730 | u->urb->transfer_dma = ep->sync_dma + i * 4; | |
731 | u->urb->transfer_buffer_length = 4; | |
732 | u->urb->pipe = ep->pipe; | |
733 | u->urb->transfer_flags = URB_ISO_ASAP | | |
734 | URB_NO_TRANSFER_DMA_MAP; | |
735 | u->urb->number_of_packets = 1; | |
736 | u->urb->interval = 1 << ep->syncinterval; | |
737 | u->urb->context = u; | |
738 | u->urb->complete = snd_complete_urb; | |
739 | } | |
740 | ||
741 | ep->nurbs = SYNC_URBS; | |
742 | ||
743 | return 0; | |
744 | ||
745 | out_of_memory: | |
746 | release_urbs(ep, 0); | |
747 | return -ENOMEM; | |
748 | } | |
749 | ||
94c27215 | 750 | /** |
07a5e9d4 | 751 | * snd_usb_endpoint_set_params: configure an snd_usb_endpoint |
94c27215 | 752 | * |
07a5e9d4 | 753 | * @ep: the snd_usb_endpoint to configure |
35ec7aa2 DR |
754 | * @pcm_format: the audio fomat. |
755 | * @channels: the number of audio channels. | |
756 | * @period_bytes: the number of bytes in one alsa period. | |
757 | * @rate: the frame rate. | |
07a5e9d4 DM |
758 | * @fmt: the USB audio format information |
759 | * @sync_ep: the sync endpoint to use, if any | |
94c27215 | 760 | * |
07a5e9d4 | 761 | * Determine the number of URBs to be used on this endpoint. |
94c27215 DM |
762 | * An endpoint must be configured before it can be started. |
763 | * An endpoint that is already running can not be reconfigured. | |
764 | */ | |
8fdff6a3 | 765 | int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep, |
35ec7aa2 DR |
766 | snd_pcm_format_t pcm_format, |
767 | unsigned int channels, | |
768 | unsigned int period_bytes, | |
769 | unsigned int rate, | |
8fdff6a3 DM |
770 | struct audioformat *fmt, |
771 | struct snd_usb_endpoint *sync_ep) | |
772 | { | |
773 | int err; | |
774 | ||
775 | if (ep->use_count != 0) { | |
776 | snd_printk(KERN_WARNING "Unable to change format on ep #%x: already in use\n", | |
777 | ep->ep_num); | |
778 | return -EBUSY; | |
779 | } | |
780 | ||
781 | /* release old buffers, if any */ | |
782 | release_urbs(ep, 0); | |
783 | ||
784 | ep->datainterval = fmt->datainterval; | |
785 | ep->maxpacksize = fmt->maxpacksize; | |
85f71932 | 786 | ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX); |
8fdff6a3 DM |
787 | |
788 | if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) | |
35ec7aa2 | 789 | ep->freqn = get_usb_full_speed_rate(rate); |
8fdff6a3 | 790 | else |
35ec7aa2 | 791 | ep->freqn = get_usb_high_speed_rate(rate); |
8fdff6a3 DM |
792 | |
793 | /* calculate the frequency in 16.16 format */ | |
794 | ep->freqm = ep->freqn; | |
795 | ep->freqshift = INT_MIN; | |
796 | ||
797 | ep->phase = 0; | |
798 | ||
799 | switch (ep->type) { | |
800 | case SND_USB_ENDPOINT_TYPE_DATA: | |
35ec7aa2 DR |
801 | err = data_ep_set_params(ep, pcm_format, channels, |
802 | period_bytes, fmt, sync_ep); | |
8fdff6a3 DM |
803 | break; |
804 | case SND_USB_ENDPOINT_TYPE_SYNC: | |
35ec7aa2 | 805 | err = sync_ep_set_params(ep, fmt); |
8fdff6a3 DM |
806 | break; |
807 | default: | |
808 | err = -EINVAL; | |
809 | } | |
810 | ||
811 | snd_printdd(KERN_DEBUG "Setting params for ep #%x (type %d, %d urbs), ret=%d\n", | |
812 | ep->ep_num, ep->type, ep->nurbs, err); | |
813 | ||
814 | return err; | |
815 | } | |
816 | ||
94c27215 DM |
817 | /** |
818 | * snd_usb_endpoint_start: start an snd_usb_endpoint | |
819 | * | |
015618b9 DM |
820 | * @ep: the endpoint to start |
821 | * @can_sleep: flag indicating whether the operation is executed in | |
822 | * non-atomic context | |
94c27215 DM |
823 | * |
824 | * A call to this function will increment the use count of the endpoint. | |
07a5e9d4 | 825 | * In case it is not already running, the URBs for this endpoint will be |
94c27215 DM |
826 | * submitted. Otherwise, this function does nothing. |
827 | * | |
828 | * Must be balanced to calls of snd_usb_endpoint_stop(). | |
829 | * | |
830 | * Returns an error if the URB submission failed, 0 in all other cases. | |
831 | */ | |
015618b9 | 832 | int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep) |
8fdff6a3 DM |
833 | { |
834 | int err; | |
835 | unsigned int i; | |
836 | ||
837 | if (ep->chip->shutdown) | |
838 | return -EBADFD; | |
839 | ||
840 | /* already running? */ | |
841 | if (++ep->use_count != 1) | |
842 | return 0; | |
843 | ||
015618b9 DM |
844 | /* just to be sure */ |
845 | deactivate_urbs(ep, 0, can_sleep); | |
846 | if (can_sleep) | |
847 | wait_clear_urbs(ep); | |
848 | ||
8fdff6a3 DM |
849 | ep->active_mask = 0; |
850 | ep->unlink_mask = 0; | |
851 | ep->phase = 0; | |
852 | ||
2b58fd5b DM |
853 | snd_usb_endpoint_start_quirk(ep); |
854 | ||
8fdff6a3 DM |
855 | /* |
856 | * If this endpoint has a data endpoint as implicit feedback source, | |
857 | * don't start the urbs here. Instead, mark them all as available, | |
07a5e9d4 DM |
858 | * wait for the record urbs to return and queue the playback urbs |
859 | * from that context. | |
8fdff6a3 DM |
860 | */ |
861 | ||
862 | set_bit(EP_FLAG_RUNNING, &ep->flags); | |
863 | ||
864 | if (snd_usb_endpoint_implict_feedback_sink(ep)) { | |
865 | for (i = 0; i < ep->nurbs; i++) { | |
866 | struct snd_urb_ctx *ctx = ep->urb + i; | |
867 | list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); | |
868 | } | |
869 | ||
870 | return 0; | |
871 | } | |
872 | ||
873 | for (i = 0; i < ep->nurbs; i++) { | |
874 | struct urb *urb = ep->urb[i].urb; | |
875 | ||
876 | if (snd_BUG_ON(!urb)) | |
877 | goto __error; | |
878 | ||
879 | if (usb_pipeout(ep->pipe)) { | |
8fdff6a3 DM |
880 | prepare_outbound_urb(ep, urb->context); |
881 | } else { | |
882 | prepare_inbound_urb(ep, urb->context); | |
883 | } | |
884 | ||
885 | err = usb_submit_urb(urb, GFP_ATOMIC); | |
886 | if (err < 0) { | |
887 | snd_printk(KERN_ERR "cannot submit urb %d, error %d: %s\n", | |
888 | i, err, usb_error_string(err)); | |
889 | goto __error; | |
890 | } | |
891 | set_bit(i, &ep->active_mask); | |
892 | } | |
893 | ||
894 | return 0; | |
895 | ||
896 | __error: | |
897 | clear_bit(EP_FLAG_RUNNING, &ep->flags); | |
898 | ep->use_count--; | |
899 | deactivate_urbs(ep, 0, 0); | |
900 | return -EPIPE; | |
901 | } | |
902 | ||
94c27215 DM |
903 | /** |
904 | * snd_usb_endpoint_stop: stop an snd_usb_endpoint | |
905 | * | |
906 | * @ep: the endpoint to stop (may be NULL) | |
907 | * | |
908 | * A call to this function will decrement the use count of the endpoint. | |
909 | * In case the last user has requested the endpoint stop, the URBs will | |
07a5e9d4 | 910 | * actually be deactivated. |
94c27215 DM |
911 | * |
912 | * Must be balanced to calls of snd_usb_endpoint_start(). | |
913 | */ | |
8fdff6a3 DM |
914 | void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, |
915 | int force, int can_sleep, int wait) | |
916 | { | |
917 | if (!ep) | |
918 | return; | |
919 | ||
920 | if (snd_BUG_ON(ep->use_count == 0)) | |
921 | return; | |
922 | ||
8fdff6a3 DM |
923 | if (--ep->use_count == 0) { |
924 | deactivate_urbs(ep, force, can_sleep); | |
925 | ep->data_subs = NULL; | |
926 | ep->sync_slave = NULL; | |
927 | ep->retire_data_urb = NULL; | |
928 | ep->prepare_data_urb = NULL; | |
929 | ||
930 | if (wait) | |
931 | wait_clear_urbs(ep); | |
f58161ba TI |
932 | else |
933 | set_bit(EP_FLAG_STOPPING, &ep->flags); | |
8fdff6a3 DM |
934 | } |
935 | } | |
936 | ||
94c27215 DM |
937 | /** |
938 | * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint | |
939 | * | |
940 | * @ep: the endpoint to deactivate | |
941 | * | |
942 | * If the endpoint is not currently in use, this functions will select the | |
943 | * alternate interface setting 0 for the interface of this endpoint. | |
944 | * | |
945 | * In case of any active users, this functions does nothing. | |
946 | * | |
947 | * Returns an error if usb_set_interface() failed, 0 in all other | |
948 | * cases. | |
949 | */ | |
8fdff6a3 DM |
950 | int snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep) |
951 | { | |
952 | if (!ep) | |
953 | return -EINVAL; | |
954 | ||
68e67f40 DM |
955 | deactivate_urbs(ep, 1, 1); |
956 | wait_clear_urbs(ep); | |
957 | ||
8fdff6a3 DM |
958 | if (ep->use_count != 0) |
959 | return 0; | |
960 | ||
68e67f40 | 961 | clear_bit(EP_FLAG_ACTIVATED, &ep->flags); |
8fdff6a3 | 962 | |
68e67f40 | 963 | return 0; |
8fdff6a3 DM |
964 | } |
965 | ||
07a5e9d4 DM |
966 | /** |
967 | * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint | |
94c27215 DM |
968 | * |
969 | * @ep: the list header of the endpoint to free | |
970 | * | |
971 | * This function does not care for the endpoint's use count but will tear | |
972 | * down all the streaming URBs immediately and free all resources. | |
973 | */ | |
8fdff6a3 DM |
974 | void snd_usb_endpoint_free(struct list_head *head) |
975 | { | |
976 | struct snd_usb_endpoint *ep; | |
977 | ||
978 | ep = list_entry(head, struct snd_usb_endpoint, list); | |
979 | release_urbs(ep, 1); | |
980 | kfree(ep); | |
981 | } | |
982 | ||
94c27215 DM |
983 | /** |
984 | * snd_usb_handle_sync_urb: parse an USB sync packet | |
985 | * | |
986 | * @ep: the endpoint to handle the packet | |
987 | * @sender: the sending endpoint | |
988 | * @urb: the received packet | |
989 | * | |
990 | * This function is called from the context of an endpoint that received | |
991 | * the packet and is used to let another endpoint object handle the payload. | |
8fdff6a3 DM |
992 | */ |
993 | void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep, | |
994 | struct snd_usb_endpoint *sender, | |
995 | const struct urb *urb) | |
996 | { | |
997 | int shift; | |
998 | unsigned int f; | |
999 | unsigned long flags; | |
1000 | ||
1001 | snd_BUG_ON(ep == sender); | |
1002 | ||
94c27215 DM |
1003 | /* |
1004 | * In case the endpoint is operating in implicit feedback mode, prepare | |
07a5e9d4 DM |
1005 | * a new outbound URB that has the same layout as the received packet |
1006 | * and add it to the list of pending urbs. queue_pending_output_urbs() | |
1007 | * will take care of them later. | |
94c27215 | 1008 | */ |
8fdff6a3 DM |
1009 | if (snd_usb_endpoint_implict_feedback_sink(ep) && |
1010 | ep->use_count != 0) { | |
1011 | ||
1012 | /* implicit feedback case */ | |
1013 | int i, bytes = 0; | |
1014 | struct snd_urb_ctx *in_ctx; | |
1015 | struct snd_usb_packet_info *out_packet; | |
1016 | ||
1017 | in_ctx = urb->context; | |
1018 | ||
1019 | /* Count overall packet size */ | |
1020 | for (i = 0; i < in_ctx->packets; i++) | |
1021 | if (urb->iso_frame_desc[i].status == 0) | |
1022 | bytes += urb->iso_frame_desc[i].actual_length; | |
1023 | ||
1024 | /* | |
1025 | * skip empty packets. At least M-Audio's Fast Track Ultra stops | |
1026 | * streaming once it received a 0-byte OUT URB | |
1027 | */ | |
1028 | if (bytes == 0) | |
1029 | return; | |
1030 | ||
1031 | spin_lock_irqsave(&ep->lock, flags); | |
1032 | out_packet = ep->next_packet + ep->next_packet_write_pos; | |
1033 | ||
1034 | /* | |
1035 | * Iterate through the inbound packet and prepare the lengths | |
1036 | * for the output packet. The OUT packet we are about to send | |
07a5e9d4 DM |
1037 | * will have the same amount of payload bytes than the IN |
1038 | * packet we just received. | |
8fdff6a3 DM |
1039 | */ |
1040 | ||
1041 | out_packet->packets = in_ctx->packets; | |
1042 | for (i = 0; i < in_ctx->packets; i++) { | |
1043 | if (urb->iso_frame_desc[i].status == 0) | |
1044 | out_packet->packet_size[i] = | |
1045 | urb->iso_frame_desc[i].actual_length / ep->stride; | |
1046 | else | |
1047 | out_packet->packet_size[i] = 0; | |
1048 | } | |
1049 | ||
1050 | ep->next_packet_write_pos++; | |
1051 | ep->next_packet_write_pos %= MAX_URBS; | |
1052 | spin_unlock_irqrestore(&ep->lock, flags); | |
1053 | queue_pending_output_urbs(ep); | |
1054 | ||
1055 | return; | |
1056 | } | |
1057 | ||
94c27215 DM |
1058 | /* |
1059 | * process after playback sync complete | |
1060 | * | |
1061 | * Full speed devices report feedback values in 10.14 format as samples | |
1062 | * per frame, high speed devices in 16.16 format as samples per | |
1063 | * microframe. | |
1064 | * | |
1065 | * Because the Audio Class 1 spec was written before USB 2.0, many high | |
1066 | * speed devices use a wrong interpretation, some others use an | |
1067 | * entirely different format. | |
1068 | * | |
1069 | * Therefore, we cannot predict what format any particular device uses | |
1070 | * and must detect it automatically. | |
1071 | */ | |
8fdff6a3 DM |
1072 | |
1073 | if (urb->iso_frame_desc[0].status != 0 || | |
1074 | urb->iso_frame_desc[0].actual_length < 3) | |
1075 | return; | |
1076 | ||
1077 | f = le32_to_cpup(urb->transfer_buffer); | |
1078 | if (urb->iso_frame_desc[0].actual_length == 3) | |
1079 | f &= 0x00ffffff; | |
1080 | else | |
1081 | f &= 0x0fffffff; | |
1082 | ||
1083 | if (f == 0) | |
1084 | return; | |
1085 | ||
1086 | if (unlikely(ep->freqshift == INT_MIN)) { | |
1087 | /* | |
1088 | * The first time we see a feedback value, determine its format | |
1089 | * by shifting it left or right until it matches the nominal | |
1090 | * frequency value. This assumes that the feedback does not | |
1091 | * differ from the nominal value more than +50% or -25%. | |
1092 | */ | |
1093 | shift = 0; | |
1094 | while (f < ep->freqn - ep->freqn / 4) { | |
1095 | f <<= 1; | |
1096 | shift++; | |
1097 | } | |
1098 | while (f > ep->freqn + ep->freqn / 2) { | |
1099 | f >>= 1; | |
1100 | shift--; | |
1101 | } | |
1102 | ep->freqshift = shift; | |
1103 | } else if (ep->freqshift >= 0) | |
1104 | f <<= ep->freqshift; | |
1105 | else | |
1106 | f >>= -ep->freqshift; | |
1107 | ||
1108 | if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) { | |
1109 | /* | |
1110 | * If the frequency looks valid, set it. | |
1111 | * This value is referred to in prepare_playback_urb(). | |
1112 | */ | |
1113 | spin_lock_irqsave(&ep->lock, flags); | |
1114 | ep->freqm = f; | |
1115 | spin_unlock_irqrestore(&ep->lock, flags); | |
1116 | } else { | |
1117 | /* | |
1118 | * Out of range; maybe the shift value is wrong. | |
1119 | * Reset it so that we autodetect again the next time. | |
1120 | */ | |
1121 | ep->freqshift = INT_MIN; | |
1122 | } | |
1123 | } | |
1124 |