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_ACTIVATED 0
37 #define EP_FLAG_RUNNING 1
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_implict_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 static int 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_outbound_urb_sizes(struct snd_usb_endpoint
*ep
,
187 struct snd_urb_ctx
*ctx
)
191 for (i
= 0; i
< ctx
->packets
; ++i
)
192 ctx
->packet_size
[i
] = next_packet_size(ep
);
196 * Prepare a PLAYBACK urb for submission to the bus.
198 static void prepare_outbound_urb(struct snd_usb_endpoint
*ep
,
199 struct snd_urb_ctx
*ctx
)
202 struct urb
*urb
= ctx
->urb
;
203 unsigned char *cp
= urb
->transfer_buffer
;
205 urb
->dev
= ep
->chip
->dev
; /* we need to set this at each time */
208 case SND_USB_ENDPOINT_TYPE_DATA
:
209 if (ep
->prepare_data_urb
) {
210 ep
->prepare_data_urb(ep
->data_subs
, urb
);
212 /* no data provider, so send silence */
213 unsigned int offs
= 0;
214 for (i
= 0; i
< ctx
->packets
; ++i
) {
215 int counts
= ctx
->packet_size
[i
];
216 urb
->iso_frame_desc
[i
].offset
= offs
* ep
->stride
;
217 urb
->iso_frame_desc
[i
].length
= counts
* ep
->stride
;
221 urb
->number_of_packets
= ctx
->packets
;
222 urb
->transfer_buffer_length
= offs
* ep
->stride
;
223 memset(urb
->transfer_buffer
, ep
->silence_value
,
228 case SND_USB_ENDPOINT_TYPE_SYNC
:
229 if (snd_usb_get_speed(ep
->chip
->dev
) >= USB_SPEED_HIGH
) {
231 * fill the length and offset of each urb descriptor.
232 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
234 urb
->iso_frame_desc
[0].length
= 4;
235 urb
->iso_frame_desc
[0].offset
= 0;
237 cp
[1] = ep
->freqn
>> 8;
238 cp
[2] = ep
->freqn
>> 16;
239 cp
[3] = ep
->freqn
>> 24;
242 * fill the length and offset of each urb descriptor.
243 * the fixed 10.14 frequency is passed through the pipe.
245 urb
->iso_frame_desc
[0].length
= 3;
246 urb
->iso_frame_desc
[0].offset
= 0;
247 cp
[0] = ep
->freqn
>> 2;
248 cp
[1] = ep
->freqn
>> 10;
249 cp
[2] = ep
->freqn
>> 18;
257 * Prepare a CAPTURE or SYNC urb for submission to the bus.
259 static inline void prepare_inbound_urb(struct snd_usb_endpoint
*ep
,
260 struct snd_urb_ctx
*urb_ctx
)
263 struct urb
*urb
= urb_ctx
->urb
;
265 urb
->dev
= ep
->chip
->dev
; /* we need to set this at each time */
268 case SND_USB_ENDPOINT_TYPE_DATA
:
270 for (i
= 0; i
< urb_ctx
->packets
; i
++) {
271 urb
->iso_frame_desc
[i
].offset
= offs
;
272 urb
->iso_frame_desc
[i
].length
= ep
->curpacksize
;
273 offs
+= ep
->curpacksize
;
276 urb
->transfer_buffer_length
= offs
;
277 urb
->number_of_packets
= urb_ctx
->packets
;
280 case SND_USB_ENDPOINT_TYPE_SYNC
:
281 urb
->iso_frame_desc
[0].length
= min(4u, ep
->syncmaxsize
);
282 urb
->iso_frame_desc
[0].offset
= 0;
288 * Send output urbs that have been prepared previously. URBs are dequeued
289 * from ep->ready_playback_urbs and in case there there aren't any available
290 * or there are no packets that have been prepared, this function does
293 * The reason why the functionality of sending and preparing URBs is separated
294 * is that host controllers don't guarantee the order in which they return
295 * inbound and outbound packets to their submitters.
297 * This function is only used for implicit feedback endpoints. For endpoints
298 * driven by dedicated sync endpoints, URBs are immediately re-submitted
299 * from their completion handler.
301 static void queue_pending_output_urbs(struct snd_usb_endpoint
*ep
)
303 while (test_bit(EP_FLAG_RUNNING
, &ep
->flags
)) {
306 struct snd_usb_packet_info
*uninitialized_var(packet
);
307 struct snd_urb_ctx
*ctx
= NULL
;
311 spin_lock_irqsave(&ep
->lock
, flags
);
312 if (ep
->next_packet_read_pos
!= ep
->next_packet_write_pos
) {
313 packet
= ep
->next_packet
+ ep
->next_packet_read_pos
;
314 ep
->next_packet_read_pos
++;
315 ep
->next_packet_read_pos
%= MAX_URBS
;
317 /* take URB out of FIFO */
318 if (!list_empty(&ep
->ready_playback_urbs
))
319 ctx
= list_first_entry(&ep
->ready_playback_urbs
,
320 struct snd_urb_ctx
, ready_list
);
322 spin_unlock_irqrestore(&ep
->lock
, flags
);
327 list_del_init(&ctx
->ready_list
);
330 /* copy over the length information */
331 for (i
= 0; i
< packet
->packets
; i
++)
332 ctx
->packet_size
[i
] = packet
->packet_size
[i
];
334 /* call the data handler to fill in playback data */
335 prepare_outbound_urb(ep
, ctx
);
337 err
= usb_submit_urb(ctx
->urb
, GFP_ATOMIC
);
339 snd_printk(KERN_ERR
"Unable to submit urb #%d: %d (urb %p)\n",
340 ctx
->index
, err
, ctx
->urb
);
342 set_bit(ctx
->index
, &ep
->active_mask
);
347 * complete callback for urbs
349 static void snd_complete_urb(struct urb
*urb
)
351 struct snd_urb_ctx
*ctx
= urb
->context
;
352 struct snd_usb_endpoint
*ep
= ctx
->ep
;
355 if (unlikely(urb
->status
== -ENOENT
|| /* unlinked */
356 urb
->status
== -ENODEV
|| /* device removed */
357 urb
->status
== -ECONNRESET
|| /* unlinked */
358 urb
->status
== -ESHUTDOWN
|| /* device disabled */
359 ep
->chip
->shutdown
)) /* device disconnected */
362 if (usb_pipeout(ep
->pipe
)) {
363 retire_outbound_urb(ep
, ctx
);
364 /* can be stopped during retire callback */
365 if (unlikely(!test_bit(EP_FLAG_RUNNING
, &ep
->flags
)))
368 if (snd_usb_endpoint_implict_feedback_sink(ep
)) {
371 spin_lock_irqsave(&ep
->lock
, flags
);
372 list_add_tail(&ctx
->ready_list
, &ep
->ready_playback_urbs
);
373 spin_unlock_irqrestore(&ep
->lock
, flags
);
374 queue_pending_output_urbs(ep
);
379 prepare_outbound_urb_sizes(ep
, ctx
);
380 prepare_outbound_urb(ep
, ctx
);
382 retire_inbound_urb(ep
, ctx
);
383 /* can be stopped during retire callback */
384 if (unlikely(!test_bit(EP_FLAG_RUNNING
, &ep
->flags
)))
387 prepare_inbound_urb(ep
, ctx
);
390 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
394 snd_printk(KERN_ERR
"cannot submit urb (err = %d)\n", err
);
395 //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
398 clear_bit(ctx
->index
, &ep
->active_mask
);
402 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
405 * @alts: The USB host interface
406 * @ep_num: The number of the endpoint to use
407 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
408 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
410 * If the requested endpoint has not been added to the given chip before,
411 * a new instance is created. Otherwise, a pointer to the previoulsy
412 * created instance is returned. In case of any error, NULL is returned.
414 * New endpoints will be added to chip->ep_list and must be freed by
415 * calling snd_usb_endpoint_free().
417 struct snd_usb_endpoint
*snd_usb_add_endpoint(struct snd_usb_audio
*chip
,
418 struct usb_host_interface
*alts
,
419 int ep_num
, int direction
, int type
)
422 struct snd_usb_endpoint
*ep
;
423 int is_playback
= direction
== SNDRV_PCM_STREAM_PLAYBACK
;
425 mutex_lock(&chip
->mutex
);
427 list_for_each(p
, &chip
->ep_list
) {
428 ep
= list_entry(p
, struct snd_usb_endpoint
, list
);
429 if (ep
->ep_num
== ep_num
&&
430 ep
->iface
== alts
->desc
.bInterfaceNumber
&&
431 ep
->alt_idx
== alts
->desc
.bAlternateSetting
) {
432 snd_printdd(KERN_DEBUG
"Re-using EP %x in iface %d,%d @%p\n",
433 ep_num
, ep
->iface
, ep
->alt_idx
, ep
);
438 snd_printdd(KERN_DEBUG
"Creating new %s %s endpoint #%x\n",
439 is_playback
? "playback" : "capture",
440 type
== SND_USB_ENDPOINT_TYPE_DATA
? "data" : "sync",
443 ep
= kzalloc(sizeof(*ep
), GFP_KERNEL
);
448 spin_lock_init(&ep
->lock
);
451 ep
->iface
= alts
->desc
.bInterfaceNumber
;
452 ep
->alt_idx
= alts
->desc
.bAlternateSetting
;
453 INIT_LIST_HEAD(&ep
->ready_playback_urbs
);
454 ep_num
&= USB_ENDPOINT_NUMBER_MASK
;
457 ep
->pipe
= usb_sndisocpipe(chip
->dev
, ep_num
);
459 ep
->pipe
= usb_rcvisocpipe(chip
->dev
, ep_num
);
461 if (type
== SND_USB_ENDPOINT_TYPE_SYNC
) {
462 if (get_endpoint(alts
, 1)->bLength
>= USB_DT_ENDPOINT_AUDIO_SIZE
&&
463 get_endpoint(alts
, 1)->bRefresh
>= 1 &&
464 get_endpoint(alts
, 1)->bRefresh
<= 9)
465 ep
->syncinterval
= get_endpoint(alts
, 1)->bRefresh
;
466 else if (snd_usb_get_speed(chip
->dev
) == USB_SPEED_FULL
)
467 ep
->syncinterval
= 1;
468 else if (get_endpoint(alts
, 1)->bInterval
>= 1 &&
469 get_endpoint(alts
, 1)->bInterval
<= 16)
470 ep
->syncinterval
= get_endpoint(alts
, 1)->bInterval
- 1;
472 ep
->syncinterval
= 3;
474 ep
->syncmaxsize
= le16_to_cpu(get_endpoint(alts
, 1)->wMaxPacketSize
);
477 list_add_tail(&ep
->list
, &chip
->ep_list
);
480 mutex_unlock(&chip
->mutex
);
486 * wait until all urbs are processed.
488 static int wait_clear_urbs(struct snd_usb_endpoint
*ep
)
490 unsigned long end_time
= jiffies
+ msecs_to_jiffies(1000);
496 for (i
= 0; i
< ep
->nurbs
; i
++)
497 if (test_bit(i
, &ep
->active_mask
))
503 schedule_timeout_uninterruptible(1);
504 } while (time_before(jiffies
, end_time
));
507 snd_printk(KERN_ERR
"timeout: still %d active urbs on EP #%x\n",
514 * unlink active urbs.
516 static int deactivate_urbs(struct snd_usb_endpoint
*ep
, int force
, int can_sleep
)
521 if (!force
&& ep
->chip
->shutdown
) /* to be sure... */
524 async
= !can_sleep
&& ep
->chip
->async_unlink
;
526 clear_bit(EP_FLAG_RUNNING
, &ep
->flags
);
528 INIT_LIST_HEAD(&ep
->ready_playback_urbs
);
529 ep
->next_packet_read_pos
= 0;
530 ep
->next_packet_write_pos
= 0;
532 if (!async
&& in_interrupt())
535 for (i
= 0; i
< ep
->nurbs
; i
++) {
536 if (test_bit(i
, &ep
->active_mask
)) {
537 if (!test_and_set_bit(i
, &ep
->unlink_mask
)) {
538 struct urb
*u
= ep
->urb
[i
].urb
;
551 * release an endpoint's urbs
553 static void release_urbs(struct snd_usb_endpoint
*ep
, int force
)
557 /* route incoming urbs to nirvana */
558 ep
->retire_data_urb
= NULL
;
559 ep
->prepare_data_urb
= NULL
;
562 deactivate_urbs(ep
, force
, 1);
565 for (i
= 0; i
< ep
->nurbs
; i
++)
566 release_urb_ctx(&ep
->urb
[i
]);
569 usb_free_coherent(ep
->chip
->dev
, SYNC_URBS
* 4,
570 ep
->syncbuf
, ep
->sync_dma
);
577 * configure a data endpoint
579 static int data_ep_set_params(struct snd_usb_endpoint
*ep
,
580 struct snd_pcm_hw_params
*hw_params
,
581 struct audioformat
*fmt
,
582 struct snd_usb_endpoint
*sync_ep
)
584 unsigned int maxsize
, i
, urb_packs
, total_packs
, packs_per_ms
;
585 int period_bytes
= params_period_bytes(hw_params
);
586 int format
= params_format(hw_params
);
587 int is_playback
= usb_pipeout(ep
->pipe
);
588 int frame_bits
= snd_pcm_format_physical_width(params_format(hw_params
)) *
589 params_channels(hw_params
);
591 ep
->datainterval
= fmt
->datainterval
;
592 ep
->stride
= frame_bits
>> 3;
593 ep
->silence_value
= format
== SNDRV_PCM_FORMAT_U8
? 0x80 : 0;
595 /* calculate max. frequency */
596 if (ep
->maxpacksize
) {
597 /* whatever fits into a max. size packet */
598 maxsize
= ep
->maxpacksize
;
599 ep
->freqmax
= (maxsize
/ (frame_bits
>> 3))
600 << (16 - ep
->datainterval
);
602 /* no max. packet size: just take 25% higher than nominal */
603 ep
->freqmax
= ep
->freqn
+ (ep
->freqn
>> 2);
604 maxsize
= ((ep
->freqmax
+ 0xffff) * (frame_bits
>> 3))
605 >> (16 - ep
->datainterval
);
609 ep
->curpacksize
= ep
->maxpacksize
;
611 ep
->curpacksize
= maxsize
;
613 if (snd_usb_get_speed(ep
->chip
->dev
) != USB_SPEED_FULL
)
614 packs_per_ms
= 8 >> ep
->datainterval
;
618 if (is_playback
&& !snd_usb_endpoint_implict_feedback_sink(ep
)) {
619 urb_packs
= max(ep
->chip
->nrpacks
, 1);
620 urb_packs
= min(urb_packs
, (unsigned int) MAX_PACKS
);
625 urb_packs
*= packs_per_ms
;
627 if (sync_ep
&& !snd_usb_endpoint_implict_feedback_sink(ep
))
628 urb_packs
= min(urb_packs
, 1U << sync_ep
->syncinterval
);
630 /* decide how many packets to be used */
631 if (is_playback
&& !snd_usb_endpoint_implict_feedback_sink(ep
)) {
632 unsigned int minsize
, maxpacks
;
633 /* determine how small a packet can be */
634 minsize
= (ep
->freqn
>> (16 - ep
->datainterval
))
636 /* with sync from device, assume it can be 12% lower */
638 minsize
-= minsize
>> 3;
639 minsize
= max(minsize
, 1u);
640 total_packs
= (period_bytes
+ minsize
- 1) / minsize
;
641 /* we need at least two URBs for queueing */
642 if (total_packs
< 2) {
645 /* and we don't want too long a queue either */
646 maxpacks
= max(MAX_QUEUE
* packs_per_ms
, urb_packs
* 2);
647 total_packs
= min(total_packs
, maxpacks
);
650 while (urb_packs
> 1 && urb_packs
* maxsize
>= period_bytes
)
652 total_packs
= MAX_URBS
* urb_packs
;
655 ep
->nurbs
= (total_packs
+ urb_packs
- 1) / urb_packs
;
656 if (ep
->nurbs
> MAX_URBS
) {
658 ep
->nurbs
= MAX_URBS
;
659 total_packs
= MAX_URBS
* urb_packs
;
660 } else if (ep
->nurbs
< 2) {
661 /* too little - we need at least two packets
662 * to ensure contiguous playback/capture
667 /* allocate and initialize data urbs */
668 for (i
= 0; i
< ep
->nurbs
; i
++) {
669 struct snd_urb_ctx
*u
= &ep
->urb
[i
];
672 u
->packets
= (i
+ 1) * total_packs
/ ep
->nurbs
673 - i
* total_packs
/ ep
->nurbs
;
674 u
->buffer_size
= maxsize
* u
->packets
;
676 if (fmt
->fmt_type
== UAC_FORMAT_TYPE_II
)
677 u
->packets
++; /* for transfer delimiter */
678 u
->urb
= usb_alloc_urb(u
->packets
, GFP_KERNEL
);
682 u
->urb
->transfer_buffer
=
683 usb_alloc_coherent(ep
->chip
->dev
, u
->buffer_size
,
684 GFP_KERNEL
, &u
->urb
->transfer_dma
);
685 if (!u
->urb
->transfer_buffer
)
687 u
->urb
->pipe
= ep
->pipe
;
688 u
->urb
->transfer_flags
= URB_ISO_ASAP
| URB_NO_TRANSFER_DMA_MAP
;
689 u
->urb
->interval
= 1 << ep
->datainterval
;
691 u
->urb
->complete
= snd_complete_urb
;
692 INIT_LIST_HEAD(&u
->ready_list
);
703 * configure a sync endpoint
705 static int sync_ep_set_params(struct snd_usb_endpoint
*ep
,
706 struct snd_pcm_hw_params
*hw_params
,
707 struct audioformat
*fmt
)
711 ep
->syncbuf
= usb_alloc_coherent(ep
->chip
->dev
, SYNC_URBS
* 4,
712 GFP_KERNEL
, &ep
->sync_dma
);
716 for (i
= 0; i
< SYNC_URBS
; i
++) {
717 struct snd_urb_ctx
*u
= &ep
->urb
[i
];
721 u
->urb
= usb_alloc_urb(1, GFP_KERNEL
);
724 u
->urb
->transfer_buffer
= ep
->syncbuf
+ i
* 4;
725 u
->urb
->transfer_dma
= ep
->sync_dma
+ i
* 4;
726 u
->urb
->transfer_buffer_length
= 4;
727 u
->urb
->pipe
= ep
->pipe
;
728 u
->urb
->transfer_flags
= URB_ISO_ASAP
|
729 URB_NO_TRANSFER_DMA_MAP
;
730 u
->urb
->number_of_packets
= 1;
731 u
->urb
->interval
= 1 << ep
->syncinterval
;
733 u
->urb
->complete
= snd_complete_urb
;
736 ep
->nurbs
= SYNC_URBS
;
746 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
748 * @ep: the snd_usb_endpoint to configure
749 * @hw_params: the hardware parameters
750 * @fmt: the USB audio format information
751 * @sync_ep: the sync endpoint to use, if any
753 * Determine the number of URBs to be used on this endpoint.
754 * An endpoint must be configured before it can be started.
755 * An endpoint that is already running can not be reconfigured.
757 int snd_usb_endpoint_set_params(struct snd_usb_endpoint
*ep
,
758 struct snd_pcm_hw_params
*hw_params
,
759 struct audioformat
*fmt
,
760 struct snd_usb_endpoint
*sync_ep
)
764 if (ep
->use_count
!= 0) {
765 snd_printk(KERN_WARNING
"Unable to change format on ep #%x: already in use\n",
770 /* release old buffers, if any */
773 ep
->datainterval
= fmt
->datainterval
;
774 ep
->maxpacksize
= fmt
->maxpacksize
;
775 ep
->fill_max
= !!(fmt
->attributes
& UAC_EP_CS_ATTR_FILL_MAX
);
777 if (snd_usb_get_speed(ep
->chip
->dev
) == USB_SPEED_FULL
)
778 ep
->freqn
= get_usb_full_speed_rate(params_rate(hw_params
));
780 ep
->freqn
= get_usb_high_speed_rate(params_rate(hw_params
));
782 /* calculate the frequency in 16.16 format */
783 ep
->freqm
= ep
->freqn
;
784 ep
->freqshift
= INT_MIN
;
789 case SND_USB_ENDPOINT_TYPE_DATA
:
790 err
= data_ep_set_params(ep
, hw_params
, fmt
, sync_ep
);
792 case SND_USB_ENDPOINT_TYPE_SYNC
:
793 err
= sync_ep_set_params(ep
, hw_params
, fmt
);
799 snd_printdd(KERN_DEBUG
"Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
800 ep
->ep_num
, ep
->type
, ep
->nurbs
, err
);
806 * snd_usb_endpoint_start: start an snd_usb_endpoint
808 * @ep: the endpoint to start
810 * A call to this function will increment the use count of the endpoint.
811 * In case it is not already running, the URBs for this endpoint will be
812 * submitted. Otherwise, this function does nothing.
814 * Must be balanced to calls of snd_usb_endpoint_stop().
816 * Returns an error if the URB submission failed, 0 in all other cases.
818 int snd_usb_endpoint_start(struct snd_usb_endpoint
*ep
)
823 if (ep
->chip
->shutdown
)
826 /* already running? */
827 if (++ep
->use_count
!= 1)
834 snd_usb_endpoint_start_quirk(ep
);
837 * If this endpoint has a data endpoint as implicit feedback source,
838 * don't start the urbs here. Instead, mark them all as available,
839 * wait for the record urbs to return and queue the playback urbs
843 set_bit(EP_FLAG_RUNNING
, &ep
->flags
);
845 if (snd_usb_endpoint_implict_feedback_sink(ep
)) {
846 for (i
= 0; i
< ep
->nurbs
; i
++) {
847 struct snd_urb_ctx
*ctx
= ep
->urb
+ i
;
848 list_add_tail(&ctx
->ready_list
, &ep
->ready_playback_urbs
);
854 for (i
= 0; i
< ep
->nurbs
; i
++) {
855 struct urb
*urb
= ep
->urb
[i
].urb
;
857 if (snd_BUG_ON(!urb
))
860 if (usb_pipeout(ep
->pipe
)) {
861 prepare_outbound_urb_sizes(ep
, urb
->context
);
862 prepare_outbound_urb(ep
, urb
->context
);
864 prepare_inbound_urb(ep
, urb
->context
);
867 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
869 snd_printk(KERN_ERR
"cannot submit urb %d, error %d: %s\n",
870 i
, err
, usb_error_string(err
));
873 set_bit(i
, &ep
->active_mask
);
879 clear_bit(EP_FLAG_RUNNING
, &ep
->flags
);
881 deactivate_urbs(ep
, 0, 0);
886 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
888 * @ep: the endpoint to stop (may be NULL)
890 * A call to this function will decrement the use count of the endpoint.
891 * In case the last user has requested the endpoint stop, the URBs will
892 * actually be deactivated.
894 * Must be balanced to calls of snd_usb_endpoint_start().
896 void snd_usb_endpoint_stop(struct snd_usb_endpoint
*ep
,
897 int force
, int can_sleep
, int wait
)
902 if (snd_BUG_ON(ep
->use_count
== 0))
905 if (--ep
->use_count
== 0) {
906 deactivate_urbs(ep
, force
, can_sleep
);
907 ep
->data_subs
= NULL
;
908 ep
->sync_slave
= NULL
;
909 ep
->retire_data_urb
= NULL
;
910 ep
->prepare_data_urb
= NULL
;
918 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
920 * @ep: the endpoint to deactivate
922 * If the endpoint is not currently in use, this functions will select the
923 * alternate interface setting 0 for the interface of this endpoint.
925 * In case of any active users, this functions does nothing.
927 * Returns an error if usb_set_interface() failed, 0 in all other
930 int snd_usb_endpoint_deactivate(struct snd_usb_endpoint
*ep
)
935 deactivate_urbs(ep
, 1, 1);
938 if (ep
->use_count
!= 0)
941 clear_bit(EP_FLAG_ACTIVATED
, &ep
->flags
);
947 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
949 * @ep: the list header of the endpoint to free
951 * This function does not care for the endpoint's use count but will tear
952 * down all the streaming URBs immediately and free all resources.
954 void snd_usb_endpoint_free(struct list_head
*head
)
956 struct snd_usb_endpoint
*ep
;
958 ep
= list_entry(head
, struct snd_usb_endpoint
, list
);
964 * snd_usb_handle_sync_urb: parse an USB sync packet
966 * @ep: the endpoint to handle the packet
967 * @sender: the sending endpoint
968 * @urb: the received packet
970 * This function is called from the context of an endpoint that received
971 * the packet and is used to let another endpoint object handle the payload.
973 void snd_usb_handle_sync_urb(struct snd_usb_endpoint
*ep
,
974 struct snd_usb_endpoint
*sender
,
975 const struct urb
*urb
)
981 snd_BUG_ON(ep
== sender
);
984 * In case the endpoint is operating in implicit feedback mode, prepare
985 * a new outbound URB that has the same layout as the received packet
986 * and add it to the list of pending urbs. queue_pending_output_urbs()
987 * will take care of them later.
989 if (snd_usb_endpoint_implict_feedback_sink(ep
) &&
990 ep
->use_count
!= 0) {
992 /* implicit feedback case */
994 struct snd_urb_ctx
*in_ctx
;
995 struct snd_usb_packet_info
*out_packet
;
997 in_ctx
= urb
->context
;
999 /* Count overall packet size */
1000 for (i
= 0; i
< in_ctx
->packets
; i
++)
1001 if (urb
->iso_frame_desc
[i
].status
== 0)
1002 bytes
+= urb
->iso_frame_desc
[i
].actual_length
;
1005 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1006 * streaming once it received a 0-byte OUT URB
1011 spin_lock_irqsave(&ep
->lock
, flags
);
1012 out_packet
= ep
->next_packet
+ ep
->next_packet_write_pos
;
1015 * Iterate through the inbound packet and prepare the lengths
1016 * for the output packet. The OUT packet we are about to send
1017 * will have the same amount of payload bytes than the IN
1018 * packet we just received.
1021 out_packet
->packets
= in_ctx
->packets
;
1022 for (i
= 0; i
< in_ctx
->packets
; i
++) {
1023 if (urb
->iso_frame_desc
[i
].status
== 0)
1024 out_packet
->packet_size
[i
] =
1025 urb
->iso_frame_desc
[i
].actual_length
/ ep
->stride
;
1027 out_packet
->packet_size
[i
] = 0;
1030 ep
->next_packet_write_pos
++;
1031 ep
->next_packet_write_pos
%= MAX_URBS
;
1032 spin_unlock_irqrestore(&ep
->lock
, flags
);
1033 queue_pending_output_urbs(ep
);
1039 * process after playback sync complete
1041 * Full speed devices report feedback values in 10.14 format as samples
1042 * per frame, high speed devices in 16.16 format as samples per
1045 * Because the Audio Class 1 spec was written before USB 2.0, many high
1046 * speed devices use a wrong interpretation, some others use an
1047 * entirely different format.
1049 * Therefore, we cannot predict what format any particular device uses
1050 * and must detect it automatically.
1053 if (urb
->iso_frame_desc
[0].status
!= 0 ||
1054 urb
->iso_frame_desc
[0].actual_length
< 3)
1057 f
= le32_to_cpup(urb
->transfer_buffer
);
1058 if (urb
->iso_frame_desc
[0].actual_length
== 3)
1066 if (unlikely(ep
->freqshift
== INT_MIN
)) {
1068 * The first time we see a feedback value, determine its format
1069 * by shifting it left or right until it matches the nominal
1070 * frequency value. This assumes that the feedback does not
1071 * differ from the nominal value more than +50% or -25%.
1074 while (f
< ep
->freqn
- ep
->freqn
/ 4) {
1078 while (f
> ep
->freqn
+ ep
->freqn
/ 2) {
1082 ep
->freqshift
= shift
;
1083 } else if (ep
->freqshift
>= 0)
1084 f
<<= ep
->freqshift
;
1086 f
>>= -ep
->freqshift
;
1088 if (likely(f
>= ep
->freqn
- ep
->freqn
/ 8 && f
<= ep
->freqmax
)) {
1090 * If the frequency looks valid, set it.
1091 * This value is referred to in prepare_playback_urb().
1093 spin_lock_irqsave(&ep
->lock
, flags
);
1095 spin_unlock_irqrestore(&ep
->lock
, flags
);
1098 * Out of range; maybe the shift value is wrong.
1099 * Reset it so that we autodetect again the next time.
1101 ep
->freqshift
= INT_MIN
;