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.
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.
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
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>
25 #include <sound/core.h>
26 #include <sound/pcm.h>
27 #include <sound/pcm_params.h>
36 #define EP_FLAG_RUNNING 1
37 #define EP_FLAG_STOPPING 2
40 * snd_usb_endpoint is a model that abstracts everything related to an
41 * USB endpoint and its streaming.
43 * There are functions to activate and deactivate the streaming URBs and
44 * optional callbacks to let the pcm logic handle the actual content of the
45 * packets for playback and record. Thus, the bus streaming and the audio
46 * handlers are fully decoupled.
48 * There are two different types of endpoints in audio applications.
50 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
51 * inbound and outbound traffic.
53 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
54 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
57 * Each endpoint has to be configured prior to being used by calling
58 * snd_usb_endpoint_set_params().
60 * The model incorporates a reference counting, so that multiple users
61 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
62 * only the first user will effectively start the URBs, and only the last
63 * one to stop it will tear the URBs down again.
67 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
68 * this will overflow at approx 524 kHz
70 static inline unsigned get_usb_full_speed_rate(unsigned int rate
)
72 return ((rate
<< 13) + 62) / 125;
76 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
77 * this will overflow at approx 4 MHz
79 static inline unsigned get_usb_high_speed_rate(unsigned int rate
)
81 return ((rate
<< 10) + 62) / 125;
87 static void release_urb_ctx(struct snd_urb_ctx
*u
)
90 usb_free_coherent(u
->ep
->chip
->dev
, u
->buffer_size
,
91 u
->urb
->transfer_buffer
,
92 u
->urb
->transfer_dma
);
97 static const char *usb_error_string(int err
)
103 return "endpoint not enabled";
105 return "endpoint stalled";
107 return "not enough bandwidth";
109 return "device disabled";
111 return "device suspended";
116 return "internal error";
118 return "unknown error";
123 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
125 * @ep: The snd_usb_endpoint
127 * Determine whether an endpoint is driven by an implicit feedback
128 * data endpoint source.
130 int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint
*ep
)
132 return ep
->sync_master
&&
133 ep
->sync_master
->type
== SND_USB_ENDPOINT_TYPE_DATA
&&
134 ep
->type
== SND_USB_ENDPOINT_TYPE_DATA
&&
135 usb_pipeout(ep
->pipe
);
139 * For streaming based on information derived from sync endpoints,
140 * prepare_outbound_urb_sizes() will call next_packet_size() to
141 * determine the number of samples to be sent in the next packet.
143 * For implicit feedback, next_packet_size() is unused.
145 int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint
*ep
)
151 return ep
->maxframesize
;
153 spin_lock_irqsave(&ep
->lock
, flags
);
154 ep
->phase
= (ep
->phase
& 0xffff)
155 + (ep
->freqm
<< ep
->datainterval
);
156 ret
= min(ep
->phase
>> 16, ep
->maxframesize
);
157 spin_unlock_irqrestore(&ep
->lock
, flags
);
162 static void retire_outbound_urb(struct snd_usb_endpoint
*ep
,
163 struct snd_urb_ctx
*urb_ctx
)
165 if (ep
->retire_data_urb
)
166 ep
->retire_data_urb(ep
->data_subs
, urb_ctx
->urb
);
169 static void retire_inbound_urb(struct snd_usb_endpoint
*ep
,
170 struct snd_urb_ctx
*urb_ctx
)
172 struct urb
*urb
= urb_ctx
->urb
;
174 if (unlikely(ep
->skip_packets
> 0)) {
180 snd_usb_handle_sync_urb(ep
->sync_slave
, ep
, urb
);
182 if (ep
->retire_data_urb
)
183 ep
->retire_data_urb(ep
->data_subs
, urb
);
186 static void prepare_silent_urb(struct snd_usb_endpoint
*ep
,
187 struct snd_urb_ctx
*ctx
)
189 struct urb
*urb
= ctx
->urb
;
190 unsigned int offs
= 0;
191 unsigned int extra
= 0;
192 __le32 packet_length
;
195 /* For tx_length_quirk, put packet length at start of packet */
196 if (ep
->chip
->tx_length_quirk
)
197 extra
= sizeof(packet_length
);
199 for (i
= 0; i
< ctx
->packets
; ++i
) {
204 if (ctx
->packet_size
[i
])
205 counts
= ctx
->packet_size
[i
];
207 counts
= snd_usb_endpoint_next_packet_size(ep
);
209 length
= counts
* ep
->stride
; /* number of silent bytes */
210 offset
= offs
* ep
->stride
+ extra
* i
;
211 urb
->iso_frame_desc
[i
].offset
= offset
;
212 urb
->iso_frame_desc
[i
].length
= length
+ extra
;
214 packet_length
= cpu_to_le32(length
);
215 memcpy(urb
->transfer_buffer
+ offset
,
216 &packet_length
, sizeof(packet_length
));
218 memset(urb
->transfer_buffer
+ offset
+ extra
,
219 ep
->silence_value
, length
);
223 urb
->number_of_packets
= ctx
->packets
;
224 urb
->transfer_buffer_length
= offs
* ep
->stride
+ ctx
->packets
* extra
;
228 * Prepare a PLAYBACK urb for submission to the bus.
230 static void prepare_outbound_urb(struct snd_usb_endpoint
*ep
,
231 struct snd_urb_ctx
*ctx
)
233 struct urb
*urb
= ctx
->urb
;
234 unsigned char *cp
= urb
->transfer_buffer
;
236 urb
->dev
= ep
->chip
->dev
; /* we need to set this at each time */
239 case SND_USB_ENDPOINT_TYPE_DATA
:
240 if (ep
->prepare_data_urb
) {
241 ep
->prepare_data_urb(ep
->data_subs
, urb
);
243 /* no data provider, so send silence */
244 prepare_silent_urb(ep
, ctx
);
248 case SND_USB_ENDPOINT_TYPE_SYNC
:
249 if (snd_usb_get_speed(ep
->chip
->dev
) >= USB_SPEED_HIGH
) {
251 * fill the length and offset of each urb descriptor.
252 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
254 urb
->iso_frame_desc
[0].length
= 4;
255 urb
->iso_frame_desc
[0].offset
= 0;
257 cp
[1] = ep
->freqn
>> 8;
258 cp
[2] = ep
->freqn
>> 16;
259 cp
[3] = ep
->freqn
>> 24;
262 * fill the length and offset of each urb descriptor.
263 * the fixed 10.14 frequency is passed through the pipe.
265 urb
->iso_frame_desc
[0].length
= 3;
266 urb
->iso_frame_desc
[0].offset
= 0;
267 cp
[0] = ep
->freqn
>> 2;
268 cp
[1] = ep
->freqn
>> 10;
269 cp
[2] = ep
->freqn
>> 18;
277 * Prepare a CAPTURE or SYNC urb for submission to the bus.
279 static inline void prepare_inbound_urb(struct snd_usb_endpoint
*ep
,
280 struct snd_urb_ctx
*urb_ctx
)
283 struct urb
*urb
= urb_ctx
->urb
;
285 urb
->dev
= ep
->chip
->dev
; /* we need to set this at each time */
288 case SND_USB_ENDPOINT_TYPE_DATA
:
290 for (i
= 0; i
< urb_ctx
->packets
; i
++) {
291 urb
->iso_frame_desc
[i
].offset
= offs
;
292 urb
->iso_frame_desc
[i
].length
= ep
->curpacksize
;
293 offs
+= ep
->curpacksize
;
296 urb
->transfer_buffer_length
= offs
;
297 urb
->number_of_packets
= urb_ctx
->packets
;
300 case SND_USB_ENDPOINT_TYPE_SYNC
:
301 urb
->iso_frame_desc
[0].length
= min(4u, ep
->syncmaxsize
);
302 urb
->iso_frame_desc
[0].offset
= 0;
308 * Send output urbs that have been prepared previously. URBs are dequeued
309 * from ep->ready_playback_urbs and in case there there aren't any available
310 * or there are no packets that have been prepared, this function does
313 * The reason why the functionality of sending and preparing URBs is separated
314 * is that host controllers don't guarantee the order in which they return
315 * inbound and outbound packets to their submitters.
317 * This function is only used for implicit feedback endpoints. For endpoints
318 * driven by dedicated sync endpoints, URBs are immediately re-submitted
319 * from their completion handler.
321 static void queue_pending_output_urbs(struct snd_usb_endpoint
*ep
)
323 while (test_bit(EP_FLAG_RUNNING
, &ep
->flags
)) {
326 struct snd_usb_packet_info
*uninitialized_var(packet
);
327 struct snd_urb_ctx
*ctx
= NULL
;
331 spin_lock_irqsave(&ep
->lock
, flags
);
332 if (ep
->next_packet_read_pos
!= ep
->next_packet_write_pos
) {
333 packet
= ep
->next_packet
+ ep
->next_packet_read_pos
;
334 ep
->next_packet_read_pos
++;
335 ep
->next_packet_read_pos
%= MAX_URBS
;
337 /* take URB out of FIFO */
338 if (!list_empty(&ep
->ready_playback_urbs
))
339 ctx
= list_first_entry(&ep
->ready_playback_urbs
,
340 struct snd_urb_ctx
, ready_list
);
342 spin_unlock_irqrestore(&ep
->lock
, flags
);
347 list_del_init(&ctx
->ready_list
);
350 /* copy over the length information */
351 for (i
= 0; i
< packet
->packets
; i
++)
352 ctx
->packet_size
[i
] = packet
->packet_size
[i
];
354 /* call the data handler to fill in playback data */
355 prepare_outbound_urb(ep
, ctx
);
357 err
= usb_submit_urb(ctx
->urb
, GFP_ATOMIC
);
359 usb_audio_err(ep
->chip
,
360 "Unable to submit urb #%d: %d (urb %p)\n",
361 ctx
->index
, err
, ctx
->urb
);
363 set_bit(ctx
->index
, &ep
->active_mask
);
368 * complete callback for urbs
370 static void snd_complete_urb(struct urb
*urb
)
372 struct snd_urb_ctx
*ctx
= urb
->context
;
373 struct snd_usb_endpoint
*ep
= ctx
->ep
;
374 struct snd_pcm_substream
*substream
;
378 if (unlikely(urb
->status
== -ENOENT
|| /* unlinked */
379 urb
->status
== -ENODEV
|| /* device removed */
380 urb
->status
== -ECONNRESET
|| /* unlinked */
381 urb
->status
== -ESHUTDOWN
)) /* device disabled */
383 /* device disconnected */
384 if (unlikely(atomic_read(&ep
->chip
->shutdown
)))
387 if (usb_pipeout(ep
->pipe
)) {
388 retire_outbound_urb(ep
, ctx
);
389 /* can be stopped during retire callback */
390 if (unlikely(!test_bit(EP_FLAG_RUNNING
, &ep
->flags
)))
393 if (snd_usb_endpoint_implicit_feedback_sink(ep
)) {
394 spin_lock_irqsave(&ep
->lock
, flags
);
395 list_add_tail(&ctx
->ready_list
, &ep
->ready_playback_urbs
);
396 spin_unlock_irqrestore(&ep
->lock
, flags
);
397 queue_pending_output_urbs(ep
);
402 prepare_outbound_urb(ep
, ctx
);
404 retire_inbound_urb(ep
, ctx
);
405 /* can be stopped during retire callback */
406 if (unlikely(!test_bit(EP_FLAG_RUNNING
, &ep
->flags
)))
409 prepare_inbound_urb(ep
, ctx
);
412 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
416 usb_audio_err(ep
->chip
, "cannot submit urb (err = %d)\n", err
);
417 if (ep
->data_subs
&& ep
->data_subs
->pcm_substream
) {
418 substream
= ep
->data_subs
->pcm_substream
;
419 snd_pcm_stop_xrun(substream
);
423 clear_bit(ctx
->index
, &ep
->active_mask
);
427 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
430 * @alts: The USB host interface
431 * @ep_num: The number of the endpoint to use
432 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
433 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
435 * If the requested endpoint has not been added to the given chip before,
436 * a new instance is created. Otherwise, a pointer to the previoulsy
437 * created instance is returned. In case of any error, NULL is returned.
439 * New endpoints will be added to chip->ep_list and must be freed by
440 * calling snd_usb_endpoint_free().
442 struct snd_usb_endpoint
*snd_usb_add_endpoint(struct snd_usb_audio
*chip
,
443 struct usb_host_interface
*alts
,
444 int ep_num
, int direction
, int type
)
446 struct snd_usb_endpoint
*ep
;
447 int is_playback
= direction
== SNDRV_PCM_STREAM_PLAYBACK
;
452 mutex_lock(&chip
->mutex
);
454 list_for_each_entry(ep
, &chip
->ep_list
, list
) {
455 if (ep
->ep_num
== ep_num
&&
456 ep
->iface
== alts
->desc
.bInterfaceNumber
&&
457 ep
->altsetting
== alts
->desc
.bAlternateSetting
) {
458 usb_audio_dbg(ep
->chip
,
459 "Re-using EP %x in iface %d,%d @%p\n",
460 ep_num
, ep
->iface
, ep
->altsetting
, ep
);
465 usb_audio_dbg(chip
, "Creating new %s %s endpoint #%x\n",
466 is_playback
? "playback" : "capture",
467 type
== SND_USB_ENDPOINT_TYPE_DATA
? "data" : "sync",
470 ep
= kzalloc(sizeof(*ep
), GFP_KERNEL
);
475 spin_lock_init(&ep
->lock
);
478 ep
->iface
= alts
->desc
.bInterfaceNumber
;
479 ep
->altsetting
= alts
->desc
.bAlternateSetting
;
480 INIT_LIST_HEAD(&ep
->ready_playback_urbs
);
481 ep_num
&= USB_ENDPOINT_NUMBER_MASK
;
484 ep
->pipe
= usb_sndisocpipe(chip
->dev
, ep_num
);
486 ep
->pipe
= usb_rcvisocpipe(chip
->dev
, ep_num
);
488 if (type
== SND_USB_ENDPOINT_TYPE_SYNC
) {
489 if (get_endpoint(alts
, 1)->bLength
>= USB_DT_ENDPOINT_AUDIO_SIZE
&&
490 get_endpoint(alts
, 1)->bRefresh
>= 1 &&
491 get_endpoint(alts
, 1)->bRefresh
<= 9)
492 ep
->syncinterval
= get_endpoint(alts
, 1)->bRefresh
;
493 else if (snd_usb_get_speed(chip
->dev
) == USB_SPEED_FULL
)
494 ep
->syncinterval
= 1;
495 else if (get_endpoint(alts
, 1)->bInterval
>= 1 &&
496 get_endpoint(alts
, 1)->bInterval
<= 16)
497 ep
->syncinterval
= get_endpoint(alts
, 1)->bInterval
- 1;
499 ep
->syncinterval
= 3;
501 ep
->syncmaxsize
= le16_to_cpu(get_endpoint(alts
, 1)->wMaxPacketSize
);
503 if (chip
->usb_id
== USB_ID(0x0644, 0x8038) /* TEAC UD-H01 */ &&
504 ep
->syncmaxsize
== 4)
505 ep
->udh01_fb_quirk
= 1;
508 list_add_tail(&ep
->list
, &chip
->ep_list
);
511 mutex_unlock(&chip
->mutex
);
517 * wait until all urbs are processed.
519 static int wait_clear_urbs(struct snd_usb_endpoint
*ep
)
521 unsigned long end_time
= jiffies
+ msecs_to_jiffies(1000);
525 alive
= bitmap_weight(&ep
->active_mask
, ep
->nurbs
);
529 schedule_timeout_uninterruptible(1);
530 } while (time_before(jiffies
, end_time
));
533 usb_audio_err(ep
->chip
,
534 "timeout: still %d active urbs on EP #%x\n",
536 clear_bit(EP_FLAG_STOPPING
, &ep
->flags
);
541 /* sync the pending stop operation;
542 * this function itself doesn't trigger the stop operation
544 void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint
*ep
)
546 if (ep
&& test_bit(EP_FLAG_STOPPING
, &ep
->flags
))
551 * unlink active urbs.
553 static int deactivate_urbs(struct snd_usb_endpoint
*ep
, bool force
)
557 if (!force
&& atomic_read(&ep
->chip
->shutdown
)) /* to be sure... */
560 clear_bit(EP_FLAG_RUNNING
, &ep
->flags
);
562 INIT_LIST_HEAD(&ep
->ready_playback_urbs
);
563 ep
->next_packet_read_pos
= 0;
564 ep
->next_packet_write_pos
= 0;
566 for (i
= 0; i
< ep
->nurbs
; i
++) {
567 if (test_bit(i
, &ep
->active_mask
)) {
568 if (!test_and_set_bit(i
, &ep
->unlink_mask
)) {
569 struct urb
*u
= ep
->urb
[i
].urb
;
579 * release an endpoint's urbs
581 static void release_urbs(struct snd_usb_endpoint
*ep
, int force
)
585 /* route incoming urbs to nirvana */
586 ep
->retire_data_urb
= NULL
;
587 ep
->prepare_data_urb
= NULL
;
590 deactivate_urbs(ep
, force
);
593 for (i
= 0; i
< ep
->nurbs
; i
++)
594 release_urb_ctx(&ep
->urb
[i
]);
597 usb_free_coherent(ep
->chip
->dev
, SYNC_URBS
* 4,
598 ep
->syncbuf
, ep
->sync_dma
);
605 * configure a data endpoint
607 static int data_ep_set_params(struct snd_usb_endpoint
*ep
,
608 snd_pcm_format_t pcm_format
,
609 unsigned int channels
,
610 unsigned int period_bytes
,
611 unsigned int frames_per_period
,
612 unsigned int periods_per_buffer
,
613 struct audioformat
*fmt
,
614 struct snd_usb_endpoint
*sync_ep
)
616 unsigned int maxsize
, minsize
, packs_per_ms
, max_packs_per_urb
;
617 unsigned int max_packs_per_period
, urbs_per_period
, urb_packs
;
618 unsigned int max_urbs
, i
;
619 int frame_bits
= snd_pcm_format_physical_width(pcm_format
) * channels
;
621 if (pcm_format
== SNDRV_PCM_FORMAT_DSD_U16_LE
&& fmt
->dsd_dop
) {
623 * When operating in DSD DOP mode, the size of a sample frame
624 * in hardware differs from the actual physical format width
625 * because we need to make room for the DOP markers.
627 frame_bits
+= channels
<< 3;
630 ep
->datainterval
= fmt
->datainterval
;
631 ep
->stride
= frame_bits
>> 3;
632 ep
->silence_value
= pcm_format
== SNDRV_PCM_FORMAT_U8
? 0x80 : 0;
634 /* assume max. frequency is 25% higher than nominal */
635 ep
->freqmax
= ep
->freqn
+ (ep
->freqn
>> 2);
636 /* Round up freqmax to nearest integer in order to calculate maximum
637 * packet size, which must represent a whole number of frames.
638 * This is accomplished by adding 0x0.ffff before converting the
639 * Q16.16 format into integer.
640 * In order to accurately calculate the maximum packet size when
641 * the data interval is more than 1 (i.e. ep->datainterval > 0),
642 * multiply by the data interval prior to rounding. For instance,
643 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
644 * frames with a data interval of 1, but 11 (10.25) frames with a
645 * data interval of 2.
646 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
647 * maximum datainterval value of 3, at USB full speed, higher for
648 * USB high speed, noting that ep->freqmax is in units of
649 * frames per packet in Q16.16 format.)
651 maxsize
= (((ep
->freqmax
<< ep
->datainterval
) + 0xffff) >> 16) *
653 /* but wMaxPacketSize might reduce this */
654 if (ep
->maxpacksize
&& ep
->maxpacksize
< maxsize
) {
655 /* whatever fits into a max. size packet */
656 maxsize
= ep
->maxpacksize
;
657 ep
->freqmax
= (maxsize
/ (frame_bits
>> 3))
658 << (16 - ep
->datainterval
);
662 ep
->curpacksize
= ep
->maxpacksize
;
664 ep
->curpacksize
= maxsize
;
666 if (snd_usb_get_speed(ep
->chip
->dev
) != USB_SPEED_FULL
) {
667 packs_per_ms
= 8 >> ep
->datainterval
;
668 max_packs_per_urb
= MAX_PACKS_HS
;
671 max_packs_per_urb
= MAX_PACKS
;
673 if (sync_ep
&& !snd_usb_endpoint_implicit_feedback_sink(ep
))
674 max_packs_per_urb
= min(max_packs_per_urb
,
675 1U << sync_ep
->syncinterval
);
676 max_packs_per_urb
= max(1u, max_packs_per_urb
>> ep
->datainterval
);
679 * Capture endpoints need to use small URBs because there's no way
680 * to tell in advance where the next period will end, and we don't
681 * want the next URB to complete much after the period ends.
683 * Playback endpoints with implicit sync much use the same parameters
684 * as their corresponding capture endpoint.
686 if (usb_pipein(ep
->pipe
) ||
687 snd_usb_endpoint_implicit_feedback_sink(ep
)) {
689 urb_packs
= packs_per_ms
;
691 * Wireless devices can poll at a max rate of once per 4ms.
692 * For dataintervals less than 5, increase the packet count to
693 * allow the host controller to use bursting to fill in the
696 if (snd_usb_get_speed(ep
->chip
->dev
) == USB_SPEED_WIRELESS
) {
697 int interval
= ep
->datainterval
;
698 while (interval
< 5) {
703 /* make capture URBs <= 1 ms and smaller than a period */
704 urb_packs
= min(max_packs_per_urb
, urb_packs
);
705 while (urb_packs
> 1 && urb_packs
* maxsize
>= period_bytes
)
707 ep
->nurbs
= MAX_URBS
;
710 * Playback endpoints without implicit sync are adjusted so that
711 * a period fits as evenly as possible in the smallest number of
712 * URBs. The total number of URBs is adjusted to the size of the
713 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
716 /* determine how small a packet can be */
717 minsize
= (ep
->freqn
>> (16 - ep
->datainterval
)) *
719 /* with sync from device, assume it can be 12% lower */
721 minsize
-= minsize
>> 3;
722 minsize
= max(minsize
, 1u);
724 /* how many packets will contain an entire ALSA period? */
725 max_packs_per_period
= DIV_ROUND_UP(period_bytes
, minsize
);
727 /* how many URBs will contain a period? */
728 urbs_per_period
= DIV_ROUND_UP(max_packs_per_period
,
730 /* how many packets are needed in each URB? */
731 urb_packs
= DIV_ROUND_UP(max_packs_per_period
, urbs_per_period
);
733 /* limit the number of frames in a single URB */
734 ep
->max_urb_frames
= DIV_ROUND_UP(frames_per_period
,
737 /* try to use enough URBs to contain an entire ALSA buffer */
738 max_urbs
= min((unsigned) MAX_URBS
,
739 MAX_QUEUE
* packs_per_ms
/ urb_packs
);
740 ep
->nurbs
= min(max_urbs
, urbs_per_period
* periods_per_buffer
);
743 /* allocate and initialize data urbs */
744 for (i
= 0; i
< ep
->nurbs
; i
++) {
745 struct snd_urb_ctx
*u
= &ep
->urb
[i
];
748 u
->packets
= urb_packs
;
749 u
->buffer_size
= maxsize
* u
->packets
;
751 if (fmt
->fmt_type
== UAC_FORMAT_TYPE_II
)
752 u
->packets
++; /* for transfer delimiter */
753 u
->urb
= usb_alloc_urb(u
->packets
, GFP_KERNEL
);
757 u
->urb
->transfer_buffer
=
758 usb_alloc_coherent(ep
->chip
->dev
, u
->buffer_size
,
759 GFP_KERNEL
, &u
->urb
->transfer_dma
);
760 if (!u
->urb
->transfer_buffer
)
762 u
->urb
->pipe
= ep
->pipe
;
763 u
->urb
->transfer_flags
= URB_NO_TRANSFER_DMA_MAP
;
764 u
->urb
->interval
= 1 << ep
->datainterval
;
766 u
->urb
->complete
= snd_complete_urb
;
767 INIT_LIST_HEAD(&u
->ready_list
);
778 * configure a sync endpoint
780 static int sync_ep_set_params(struct snd_usb_endpoint
*ep
)
784 ep
->syncbuf
= usb_alloc_coherent(ep
->chip
->dev
, SYNC_URBS
* 4,
785 GFP_KERNEL
, &ep
->sync_dma
);
789 for (i
= 0; i
< SYNC_URBS
; i
++) {
790 struct snd_urb_ctx
*u
= &ep
->urb
[i
];
794 u
->urb
= usb_alloc_urb(1, GFP_KERNEL
);
797 u
->urb
->transfer_buffer
= ep
->syncbuf
+ i
* 4;
798 u
->urb
->transfer_dma
= ep
->sync_dma
+ i
* 4;
799 u
->urb
->transfer_buffer_length
= 4;
800 u
->urb
->pipe
= ep
->pipe
;
801 u
->urb
->transfer_flags
= URB_NO_TRANSFER_DMA_MAP
;
802 u
->urb
->number_of_packets
= 1;
803 u
->urb
->interval
= 1 << ep
->syncinterval
;
805 u
->urb
->complete
= snd_complete_urb
;
808 ep
->nurbs
= SYNC_URBS
;
818 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
820 * @ep: the snd_usb_endpoint to configure
821 * @pcm_format: the audio fomat.
822 * @channels: the number of audio channels.
823 * @period_bytes: the number of bytes in one alsa period.
824 * @period_frames: the number of frames in one alsa period.
825 * @buffer_periods: the number of periods in one alsa buffer.
826 * @rate: the frame rate.
827 * @fmt: the USB audio format information
828 * @sync_ep: the sync endpoint to use, if any
830 * Determine the number of URBs to be used on this endpoint.
831 * An endpoint must be configured before it can be started.
832 * An endpoint that is already running can not be reconfigured.
834 int snd_usb_endpoint_set_params(struct snd_usb_endpoint
*ep
,
835 snd_pcm_format_t pcm_format
,
836 unsigned int channels
,
837 unsigned int period_bytes
,
838 unsigned int period_frames
,
839 unsigned int buffer_periods
,
841 struct audioformat
*fmt
,
842 struct snd_usb_endpoint
*sync_ep
)
846 if (ep
->use_count
!= 0) {
847 usb_audio_warn(ep
->chip
,
848 "Unable to change format on ep #%x: already in use\n",
853 /* release old buffers, if any */
856 ep
->datainterval
= fmt
->datainterval
;
857 ep
->maxpacksize
= fmt
->maxpacksize
;
858 ep
->fill_max
= !!(fmt
->attributes
& UAC_EP_CS_ATTR_FILL_MAX
);
860 if (snd_usb_get_speed(ep
->chip
->dev
) == USB_SPEED_FULL
)
861 ep
->freqn
= get_usb_full_speed_rate(rate
);
863 ep
->freqn
= get_usb_high_speed_rate(rate
);
865 /* calculate the frequency in 16.16 format */
866 ep
->freqm
= ep
->freqn
;
867 ep
->freqshift
= INT_MIN
;
872 case SND_USB_ENDPOINT_TYPE_DATA
:
873 err
= data_ep_set_params(ep
, pcm_format
, channels
,
874 period_bytes
, period_frames
,
875 buffer_periods
, fmt
, sync_ep
);
877 case SND_USB_ENDPOINT_TYPE_SYNC
:
878 err
= sync_ep_set_params(ep
);
884 usb_audio_dbg(ep
->chip
,
885 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
886 ep
->ep_num
, ep
->type
, ep
->nurbs
, err
);
892 * snd_usb_endpoint_start: start an snd_usb_endpoint
894 * @ep: the endpoint to start
895 * @can_sleep: flag indicating whether the operation is executed in
898 * A call to this function will increment the use count of the endpoint.
899 * In case it is not already running, the URBs for this endpoint will be
900 * submitted. Otherwise, this function does nothing.
902 * Must be balanced to calls of snd_usb_endpoint_stop().
904 * Returns an error if the URB submission failed, 0 in all other cases.
906 int snd_usb_endpoint_start(struct snd_usb_endpoint
*ep
, bool can_sleep
)
911 if (atomic_read(&ep
->chip
->shutdown
))
914 /* already running? */
915 if (++ep
->use_count
!= 1)
918 /* just to be sure */
919 deactivate_urbs(ep
, false);
927 snd_usb_endpoint_start_quirk(ep
);
930 * If this endpoint has a data endpoint as implicit feedback source,
931 * don't start the urbs here. Instead, mark them all as available,
932 * wait for the record urbs to return and queue the playback urbs
936 set_bit(EP_FLAG_RUNNING
, &ep
->flags
);
938 if (snd_usb_endpoint_implicit_feedback_sink(ep
)) {
939 for (i
= 0; i
< ep
->nurbs
; i
++) {
940 struct snd_urb_ctx
*ctx
= ep
->urb
+ i
;
941 list_add_tail(&ctx
->ready_list
, &ep
->ready_playback_urbs
);
947 for (i
= 0; i
< ep
->nurbs
; i
++) {
948 struct urb
*urb
= ep
->urb
[i
].urb
;
950 if (snd_BUG_ON(!urb
))
953 if (usb_pipeout(ep
->pipe
)) {
954 prepare_outbound_urb(ep
, urb
->context
);
956 prepare_inbound_urb(ep
, urb
->context
);
959 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
961 usb_audio_err(ep
->chip
,
962 "cannot submit urb %d, error %d: %s\n",
963 i
, err
, usb_error_string(err
));
966 set_bit(i
, &ep
->active_mask
);
972 clear_bit(EP_FLAG_RUNNING
, &ep
->flags
);
974 deactivate_urbs(ep
, false);
979 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
981 * @ep: the endpoint to stop (may be NULL)
983 * A call to this function will decrement the use count of the endpoint.
984 * In case the last user has requested the endpoint stop, the URBs will
985 * actually be deactivated.
987 * Must be balanced to calls of snd_usb_endpoint_start().
989 * The caller needs to synchronize the pending stop operation via
990 * snd_usb_endpoint_sync_pending_stop().
992 void snd_usb_endpoint_stop(struct snd_usb_endpoint
*ep
)
997 if (snd_BUG_ON(ep
->use_count
== 0))
1000 if (--ep
->use_count
== 0) {
1001 deactivate_urbs(ep
, false);
1002 ep
->data_subs
= NULL
;
1003 ep
->sync_slave
= NULL
;
1004 ep
->retire_data_urb
= NULL
;
1005 ep
->prepare_data_urb
= NULL
;
1006 set_bit(EP_FLAG_STOPPING
, &ep
->flags
);
1011 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
1013 * @ep: the endpoint to deactivate
1015 * If the endpoint is not currently in use, this functions will
1016 * deactivate its associated URBs.
1018 * In case of any active users, this functions does nothing.
1020 void snd_usb_endpoint_deactivate(struct snd_usb_endpoint
*ep
)
1025 if (ep
->use_count
!= 0)
1028 deactivate_urbs(ep
, true);
1029 wait_clear_urbs(ep
);
1033 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1035 * @ep: the endpoint to release
1037 * This function does not care for the endpoint's use count but will tear
1038 * down all the streaming URBs immediately.
1040 void snd_usb_endpoint_release(struct snd_usb_endpoint
*ep
)
1042 release_urbs(ep
, 1);
1046 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1048 * @ep: the endpoint to free
1050 * This free all resources of the given ep.
1052 void snd_usb_endpoint_free(struct snd_usb_endpoint
*ep
)
1058 * snd_usb_handle_sync_urb: parse an USB sync packet
1060 * @ep: the endpoint to handle the packet
1061 * @sender: the sending endpoint
1062 * @urb: the received packet
1064 * This function is called from the context of an endpoint that received
1065 * the packet and is used to let another endpoint object handle the payload.
1067 void snd_usb_handle_sync_urb(struct snd_usb_endpoint
*ep
,
1068 struct snd_usb_endpoint
*sender
,
1069 const struct urb
*urb
)
1073 unsigned long flags
;
1075 snd_BUG_ON(ep
== sender
);
1078 * In case the endpoint is operating in implicit feedback mode, prepare
1079 * a new outbound URB that has the same layout as the received packet
1080 * and add it to the list of pending urbs. queue_pending_output_urbs()
1081 * will take care of them later.
1083 if (snd_usb_endpoint_implicit_feedback_sink(ep
) &&
1084 ep
->use_count
!= 0) {
1086 /* implicit feedback case */
1088 struct snd_urb_ctx
*in_ctx
;
1089 struct snd_usb_packet_info
*out_packet
;
1091 in_ctx
= urb
->context
;
1093 /* Count overall packet size */
1094 for (i
= 0; i
< in_ctx
->packets
; i
++)
1095 if (urb
->iso_frame_desc
[i
].status
== 0)
1096 bytes
+= urb
->iso_frame_desc
[i
].actual_length
;
1099 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1100 * streaming once it received a 0-byte OUT URB
1105 spin_lock_irqsave(&ep
->lock
, flags
);
1106 out_packet
= ep
->next_packet
+ ep
->next_packet_write_pos
;
1109 * Iterate through the inbound packet and prepare the lengths
1110 * for the output packet. The OUT packet we are about to send
1111 * will have the same amount of payload bytes per stride as the
1112 * IN packet we just received. Since the actual size is scaled
1113 * by the stride, use the sender stride to calculate the length
1114 * in case the number of channels differ between the implicitly
1115 * fed-back endpoint and the synchronizing endpoint.
1118 out_packet
->packets
= in_ctx
->packets
;
1119 for (i
= 0; i
< in_ctx
->packets
; i
++) {
1120 if (urb
->iso_frame_desc
[i
].status
== 0)
1121 out_packet
->packet_size
[i
] =
1122 urb
->iso_frame_desc
[i
].actual_length
/ sender
->stride
;
1124 out_packet
->packet_size
[i
] = 0;
1127 ep
->next_packet_write_pos
++;
1128 ep
->next_packet_write_pos
%= MAX_URBS
;
1129 spin_unlock_irqrestore(&ep
->lock
, flags
);
1130 queue_pending_output_urbs(ep
);
1136 * process after playback sync complete
1138 * Full speed devices report feedback values in 10.14 format as samples
1139 * per frame, high speed devices in 16.16 format as samples per
1142 * Because the Audio Class 1 spec was written before USB 2.0, many high
1143 * speed devices use a wrong interpretation, some others use an
1144 * entirely different format.
1146 * Therefore, we cannot predict what format any particular device uses
1147 * and must detect it automatically.
1150 if (urb
->iso_frame_desc
[0].status
!= 0 ||
1151 urb
->iso_frame_desc
[0].actual_length
< 3)
1154 f
= le32_to_cpup(urb
->transfer_buffer
);
1155 if (urb
->iso_frame_desc
[0].actual_length
== 3)
1163 if (unlikely(sender
->udh01_fb_quirk
)) {
1165 * The TEAC UD-H01 firmware sometimes changes the feedback value
1168 if (f
< ep
->freqn
- 0x8000)
1170 else if (f
> ep
->freqn
+ 0x8000)
1172 } else if (unlikely(ep
->freqshift
== INT_MIN
)) {
1174 * The first time we see a feedback value, determine its format
1175 * by shifting it left or right until it matches the nominal
1176 * frequency value. This assumes that the feedback does not
1177 * differ from the nominal value more than +50% or -25%.
1180 while (f
< ep
->freqn
- ep
->freqn
/ 4) {
1184 while (f
> ep
->freqn
+ ep
->freqn
/ 2) {
1188 ep
->freqshift
= shift
;
1189 } else if (ep
->freqshift
>= 0)
1190 f
<<= ep
->freqshift
;
1192 f
>>= -ep
->freqshift
;
1194 if (likely(f
>= ep
->freqn
- ep
->freqn
/ 8 && f
<= ep
->freqmax
)) {
1196 * If the frequency looks valid, set it.
1197 * This value is referred to in prepare_playback_urb().
1199 spin_lock_irqsave(&ep
->lock
, flags
);
1201 spin_unlock_irqrestore(&ep
->lock
, flags
);
1204 * Out of range; maybe the shift value is wrong.
1205 * Reset it so that we autodetect again the next time.
1207 ep
->freqshift
= INT_MIN
;