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>
35 #define EP_FLAG_ACTIVATED 0
36 #define EP_FLAG_RUNNING 1
39 * snd_usb_endpoint is a model that abstracts everything related to an
40 * USB endpoint and its streaming.
42 * There are functions to activate and deactivate the streaming URBs and
43 * optional callbacks to let the pcm logic handle the actual content of the
44 * packets for playback and record. Thus, the bus streaming and the audio
45 * handlers are fully decoupled.
47 * There are two different types of endpoints in audio applications.
49 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
50 * inbound and outbound traffic.
52 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
53 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
56 * Each endpoint has to be configured prior to being used by calling
57 * snd_usb_endpoint_set_params().
59 * The model incorporates a reference counting, so that multiple users
60 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
61 * only the first user will effectively start the URBs, and only the last
62 * one to stop it will tear the URBs down again.
66 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
67 * this will overflow at approx 524 kHz
69 static inline unsigned get_usb_full_speed_rate(unsigned int rate
)
71 return ((rate
<< 13) + 62) / 125;
75 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
76 * this will overflow at approx 4 MHz
78 static inline unsigned get_usb_high_speed_rate(unsigned int rate
)
80 return ((rate
<< 10) + 62) / 125;
86 static void release_urb_ctx(struct snd_urb_ctx
*u
)
89 usb_free_coherent(u
->ep
->chip
->dev
, u
->buffer_size
,
90 u
->urb
->transfer_buffer
,
91 u
->urb
->transfer_dma
);
96 static const char *usb_error_string(int err
)
102 return "endpoint not enabled";
104 return "endpoint stalled";
106 return "not enough bandwidth";
108 return "device disabled";
110 return "device suspended";
115 return "internal error";
117 return "unknown error";
122 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
124 * @ep: The snd_usb_endpoint
126 * Determine whether an endpoint is driven by an implicit feedback
127 * data endpoint source.
129 int snd_usb_endpoint_implict_feedback_sink(struct snd_usb_endpoint
*ep
)
131 return ep
->sync_master
&&
132 ep
->sync_master
->type
== SND_USB_ENDPOINT_TYPE_DATA
&&
133 ep
->type
== SND_USB_ENDPOINT_TYPE_DATA
&&
134 usb_pipeout(ep
->pipe
);
138 * For streaming based on information derived from sync endpoints,
139 * prepare_outbound_urb_sizes() will call next_packet_size() to
140 * determine the number of samples to be sent in the next packet.
142 * For implicit feedback, next_packet_size() is unused.
144 static int next_packet_size(struct snd_usb_endpoint
*ep
)
150 return ep
->maxframesize
;
152 spin_lock_irqsave(&ep
->lock
, flags
);
153 ep
->phase
= (ep
->phase
& 0xffff)
154 + (ep
->freqm
<< ep
->datainterval
);
155 ret
= min(ep
->phase
>> 16, ep
->maxframesize
);
156 spin_unlock_irqrestore(&ep
->lock
, flags
);
161 static void retire_outbound_urb(struct snd_usb_endpoint
*ep
,
162 struct snd_urb_ctx
*urb_ctx
)
164 if (ep
->retire_data_urb
)
165 ep
->retire_data_urb(ep
->data_subs
, urb_ctx
->urb
);
168 static void retire_inbound_urb(struct snd_usb_endpoint
*ep
,
169 struct snd_urb_ctx
*urb_ctx
)
171 struct urb
*urb
= urb_ctx
->urb
;
174 snd_usb_handle_sync_urb(ep
->sync_slave
, ep
, urb
);
176 if (ep
->retire_data_urb
)
177 ep
->retire_data_urb(ep
->data_subs
, urb
);
180 static void prepare_outbound_urb_sizes(struct snd_usb_endpoint
*ep
,
181 struct snd_urb_ctx
*ctx
)
185 for (i
= 0; i
< ctx
->packets
; ++i
)
186 ctx
->packet_size
[i
] = next_packet_size(ep
);
190 * Prepare a PLAYBACK urb for submission to the bus.
192 static void prepare_outbound_urb(struct snd_usb_endpoint
*ep
,
193 struct snd_urb_ctx
*ctx
)
196 struct urb
*urb
= ctx
->urb
;
197 unsigned char *cp
= urb
->transfer_buffer
;
199 urb
->dev
= ep
->chip
->dev
; /* we need to set this at each time */
202 case SND_USB_ENDPOINT_TYPE_DATA
:
203 if (ep
->prepare_data_urb
) {
204 ep
->prepare_data_urb(ep
->data_subs
, urb
);
206 /* no data provider, so send silence */
207 unsigned int offs
= 0;
208 for (i
= 0; i
< ctx
->packets
; ++i
) {
209 int counts
= ctx
->packet_size
[i
];
210 urb
->iso_frame_desc
[i
].offset
= offs
* ep
->stride
;
211 urb
->iso_frame_desc
[i
].length
= counts
* ep
->stride
;
215 urb
->number_of_packets
= ctx
->packets
;
216 urb
->transfer_buffer_length
= offs
* ep
->stride
;
217 memset(urb
->transfer_buffer
, ep
->silence_value
,
222 case SND_USB_ENDPOINT_TYPE_SYNC
:
223 if (snd_usb_get_speed(ep
->chip
->dev
) >= USB_SPEED_HIGH
) {
225 * fill the length and offset of each urb descriptor.
226 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
228 urb
->iso_frame_desc
[0].length
= 4;
229 urb
->iso_frame_desc
[0].offset
= 0;
231 cp
[1] = ep
->freqn
>> 8;
232 cp
[2] = ep
->freqn
>> 16;
233 cp
[3] = ep
->freqn
>> 24;
236 * fill the length and offset of each urb descriptor.
237 * the fixed 10.14 frequency is passed through the pipe.
239 urb
->iso_frame_desc
[0].length
= 3;
240 urb
->iso_frame_desc
[0].offset
= 0;
241 cp
[0] = ep
->freqn
>> 2;
242 cp
[1] = ep
->freqn
>> 10;
243 cp
[2] = ep
->freqn
>> 18;
251 * Prepare a CAPTURE or SYNC urb for submission to the bus.
253 static inline void prepare_inbound_urb(struct snd_usb_endpoint
*ep
,
254 struct snd_urb_ctx
*urb_ctx
)
257 struct urb
*urb
= urb_ctx
->urb
;
259 urb
->dev
= ep
->chip
->dev
; /* we need to set this at each time */
262 case SND_USB_ENDPOINT_TYPE_DATA
:
264 for (i
= 0; i
< urb_ctx
->packets
; i
++) {
265 urb
->iso_frame_desc
[i
].offset
= offs
;
266 urb
->iso_frame_desc
[i
].length
= ep
->curpacksize
;
267 offs
+= ep
->curpacksize
;
270 urb
->transfer_buffer_length
= offs
;
271 urb
->number_of_packets
= urb_ctx
->packets
;
274 case SND_USB_ENDPOINT_TYPE_SYNC
:
275 urb
->iso_frame_desc
[0].length
= min(4u, ep
->syncmaxsize
);
276 urb
->iso_frame_desc
[0].offset
= 0;
282 * Send output urbs that have been prepared previously. URBs are dequeued
283 * from ep->ready_playback_urbs and in case there there aren't any available
284 * or there are no packets that have been prepared, this function does
287 * The reason why the functionality of sending and preparing URBs is separated
288 * is that host controllers don't guarantee the order in which they return
289 * inbound and outbound packets to their submitters.
291 * This function is only used for implicit feedback endpoints. For endpoints
292 * driven by dedicated sync endpoints, URBs are immediately re-submitted
293 * from their completion handler.
295 static void queue_pending_output_urbs(struct snd_usb_endpoint
*ep
)
297 while (test_bit(EP_FLAG_RUNNING
, &ep
->flags
)) {
300 struct snd_usb_packet_info
*uninitialized_var(packet
);
301 struct snd_urb_ctx
*ctx
= NULL
;
305 spin_lock_irqsave(&ep
->lock
, flags
);
306 if (ep
->next_packet_read_pos
!= ep
->next_packet_write_pos
) {
307 packet
= ep
->next_packet
+ ep
->next_packet_read_pos
;
308 ep
->next_packet_read_pos
++;
309 ep
->next_packet_read_pos
%= MAX_URBS
;
311 /* take URB out of FIFO */
312 if (!list_empty(&ep
->ready_playback_urbs
))
313 ctx
= list_first_entry(&ep
->ready_playback_urbs
,
314 struct snd_urb_ctx
, ready_list
);
316 spin_unlock_irqrestore(&ep
->lock
, flags
);
321 list_del_init(&ctx
->ready_list
);
324 /* copy over the length information */
325 for (i
= 0; i
< packet
->packets
; i
++)
326 ctx
->packet_size
[i
] = packet
->packet_size
[i
];
328 /* call the data handler to fill in playback data */
329 prepare_outbound_urb(ep
, ctx
);
331 err
= usb_submit_urb(ctx
->urb
, GFP_ATOMIC
);
333 snd_printk(KERN_ERR
"Unable to submit urb #%d: %d (urb %p)\n",
334 ctx
->index
, err
, ctx
->urb
);
336 set_bit(ctx
->index
, &ep
->active_mask
);
341 * complete callback for urbs
343 static void snd_complete_urb(struct urb
*urb
)
345 struct snd_urb_ctx
*ctx
= urb
->context
;
346 struct snd_usb_endpoint
*ep
= ctx
->ep
;
349 if (unlikely(urb
->status
== -ENOENT
|| /* unlinked */
350 urb
->status
== -ENODEV
|| /* device removed */
351 urb
->status
== -ECONNRESET
|| /* unlinked */
352 urb
->status
== -ESHUTDOWN
|| /* device disabled */
353 ep
->chip
->shutdown
)) /* device disconnected */
356 if (usb_pipeout(ep
->pipe
)) {
357 retire_outbound_urb(ep
, ctx
);
358 /* can be stopped during retire callback */
359 if (unlikely(!test_bit(EP_FLAG_RUNNING
, &ep
->flags
)))
362 if (snd_usb_endpoint_implict_feedback_sink(ep
)) {
365 spin_lock_irqsave(&ep
->lock
, flags
);
366 list_add_tail(&ctx
->ready_list
, &ep
->ready_playback_urbs
);
367 spin_unlock_irqrestore(&ep
->lock
, flags
);
368 queue_pending_output_urbs(ep
);
373 prepare_outbound_urb_sizes(ep
, ctx
);
374 prepare_outbound_urb(ep
, ctx
);
376 retire_inbound_urb(ep
, ctx
);
377 /* can be stopped during retire callback */
378 if (unlikely(!test_bit(EP_FLAG_RUNNING
, &ep
->flags
)))
381 prepare_inbound_urb(ep
, ctx
);
384 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
388 snd_printk(KERN_ERR
"cannot submit urb (err = %d)\n", err
);
389 //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
392 clear_bit(ctx
->index
, &ep
->active_mask
);
396 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
399 * @alts: The USB host interface
400 * @ep_num: The number of the endpoint to use
401 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
402 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
404 * If the requested endpoint has not been added to the given chip before,
405 * a new instance is created. Otherwise, a pointer to the previoulsy
406 * created instance is returned. In case of any error, NULL is returned.
408 * New endpoints will be added to chip->ep_list and must be freed by
409 * calling snd_usb_endpoint_free().
411 struct snd_usb_endpoint
*snd_usb_add_endpoint(struct snd_usb_audio
*chip
,
412 struct usb_host_interface
*alts
,
413 int ep_num
, int direction
, int type
)
416 struct snd_usb_endpoint
*ep
;
417 int ret
, is_playback
= direction
== SNDRV_PCM_STREAM_PLAYBACK
;
419 mutex_lock(&chip
->mutex
);
421 list_for_each(p
, &chip
->ep_list
) {
422 ep
= list_entry(p
, struct snd_usb_endpoint
, list
);
423 if (ep
->ep_num
== ep_num
&&
424 ep
->iface
== alts
->desc
.bInterfaceNumber
&&
425 ep
->alt_idx
== alts
->desc
.bAlternateSetting
) {
426 snd_printdd(KERN_DEBUG
"Re-using EP %x in iface %d,%d @%p\n",
427 ep_num
, ep
->iface
, ep
->alt_idx
, ep
);
432 snd_printdd(KERN_DEBUG
"Creating new %s %s endpoint #%x\n",
433 is_playback
? "playback" : "capture",
434 type
== SND_USB_ENDPOINT_TYPE_DATA
? "data" : "sync",
437 /* select the alt setting once so the endpoints become valid */
438 ret
= usb_set_interface(chip
->dev
, alts
->desc
.bInterfaceNumber
,
439 alts
->desc
.bAlternateSetting
);
441 snd_printk(KERN_ERR
"%s(): usb_set_interface() failed, ret = %d\n",
447 ep
= kzalloc(sizeof(*ep
), GFP_KERNEL
);
452 spin_lock_init(&ep
->lock
);
455 ep
->iface
= alts
->desc
.bInterfaceNumber
;
456 ep
->alt_idx
= alts
->desc
.bAlternateSetting
;
457 INIT_LIST_HEAD(&ep
->ready_playback_urbs
);
458 ep_num
&= USB_ENDPOINT_NUMBER_MASK
;
461 ep
->pipe
= usb_sndisocpipe(chip
->dev
, ep_num
);
463 ep
->pipe
= usb_rcvisocpipe(chip
->dev
, ep_num
);
465 if (type
== SND_USB_ENDPOINT_TYPE_SYNC
) {
466 if (get_endpoint(alts
, 1)->bLength
>= USB_DT_ENDPOINT_AUDIO_SIZE
&&
467 get_endpoint(alts
, 1)->bRefresh
>= 1 &&
468 get_endpoint(alts
, 1)->bRefresh
<= 9)
469 ep
->syncinterval
= get_endpoint(alts
, 1)->bRefresh
;
470 else if (snd_usb_get_speed(chip
->dev
) == USB_SPEED_FULL
)
471 ep
->syncinterval
= 1;
472 else if (get_endpoint(alts
, 1)->bInterval
>= 1 &&
473 get_endpoint(alts
, 1)->bInterval
<= 16)
474 ep
->syncinterval
= get_endpoint(alts
, 1)->bInterval
- 1;
476 ep
->syncinterval
= 3;
478 ep
->syncmaxsize
= le16_to_cpu(get_endpoint(alts
, 1)->wMaxPacketSize
);
481 list_add_tail(&ep
->list
, &chip
->ep_list
);
484 mutex_unlock(&chip
->mutex
);
490 * wait until all urbs are processed.
492 static int wait_clear_urbs(struct snd_usb_endpoint
*ep
)
494 unsigned long end_time
= jiffies
+ msecs_to_jiffies(1000);
500 for (i
= 0; i
< ep
->nurbs
; i
++)
501 if (test_bit(i
, &ep
->active_mask
))
507 schedule_timeout_uninterruptible(1);
508 } while (time_before(jiffies
, end_time
));
511 snd_printk(KERN_ERR
"timeout: still %d active urbs on EP #%x\n",
518 * unlink active urbs.
520 static int deactivate_urbs(struct snd_usb_endpoint
*ep
, int force
, int can_sleep
)
525 if (!force
&& ep
->chip
->shutdown
) /* to be sure... */
528 async
= !can_sleep
&& ep
->chip
->async_unlink
;
530 clear_bit(EP_FLAG_RUNNING
, &ep
->flags
);
532 INIT_LIST_HEAD(&ep
->ready_playback_urbs
);
533 ep
->next_packet_read_pos
= 0;
534 ep
->next_packet_write_pos
= 0;
536 if (!async
&& in_interrupt())
539 for (i
= 0; i
< ep
->nurbs
; i
++) {
540 if (test_bit(i
, &ep
->active_mask
)) {
541 if (!test_and_set_bit(i
, &ep
->unlink_mask
)) {
542 struct urb
*u
= ep
->urb
[i
].urb
;
555 * release an endpoint's urbs
557 static void release_urbs(struct snd_usb_endpoint
*ep
, int force
)
561 /* route incoming urbs to nirvana */
562 ep
->retire_data_urb
= NULL
;
563 ep
->prepare_data_urb
= NULL
;
566 deactivate_urbs(ep
, force
, 1);
569 for (i
= 0; i
< ep
->nurbs
; i
++)
570 release_urb_ctx(&ep
->urb
[i
]);
573 usb_free_coherent(ep
->chip
->dev
, SYNC_URBS
* 4,
574 ep
->syncbuf
, ep
->sync_dma
);
581 * configure a data endpoint
583 static int data_ep_set_params(struct snd_usb_endpoint
*ep
,
584 struct snd_pcm_hw_params
*hw_params
,
585 struct audioformat
*fmt
,
586 struct snd_usb_endpoint
*sync_ep
)
588 unsigned int maxsize
, i
, urb_packs
, total_packs
, packs_per_ms
;
589 int period_bytes
= params_period_bytes(hw_params
);
590 int format
= params_format(hw_params
);
591 int is_playback
= usb_pipeout(ep
->pipe
);
592 int frame_bits
= snd_pcm_format_physical_width(params_format(hw_params
)) *
593 params_channels(hw_params
);
595 ep
->datainterval
= fmt
->datainterval
;
596 ep
->stride
= frame_bits
>> 3;
597 ep
->silence_value
= format
== SNDRV_PCM_FORMAT_U8
? 0x80 : 0;
599 /* calculate max. frequency */
600 if (ep
->maxpacksize
) {
601 /* whatever fits into a max. size packet */
602 maxsize
= ep
->maxpacksize
;
603 ep
->freqmax
= (maxsize
/ (frame_bits
>> 3))
604 << (16 - ep
->datainterval
);
606 /* no max. packet size: just take 25% higher than nominal */
607 ep
->freqmax
= ep
->freqn
+ (ep
->freqn
>> 2);
608 maxsize
= ((ep
->freqmax
+ 0xffff) * (frame_bits
>> 3))
609 >> (16 - ep
->datainterval
);
613 ep
->curpacksize
= ep
->maxpacksize
;
615 ep
->curpacksize
= maxsize
;
617 if (snd_usb_get_speed(ep
->chip
->dev
) != USB_SPEED_FULL
)
618 packs_per_ms
= 8 >> ep
->datainterval
;
622 if (is_playback
&& !snd_usb_endpoint_implict_feedback_sink(ep
)) {
623 urb_packs
= max(ep
->chip
->nrpacks
, 1);
624 urb_packs
= min(urb_packs
, (unsigned int) MAX_PACKS
);
629 urb_packs
*= packs_per_ms
;
631 if (sync_ep
&& !snd_usb_endpoint_implict_feedback_sink(ep
))
632 urb_packs
= min(urb_packs
, 1U << sync_ep
->syncinterval
);
634 /* decide how many packets to be used */
635 if (is_playback
&& !snd_usb_endpoint_implict_feedback_sink(ep
)) {
636 unsigned int minsize
, maxpacks
;
637 /* determine how small a packet can be */
638 minsize
= (ep
->freqn
>> (16 - ep
->datainterval
))
640 /* with sync from device, assume it can be 12% lower */
642 minsize
-= minsize
>> 3;
643 minsize
= max(minsize
, 1u);
644 total_packs
= (period_bytes
+ minsize
- 1) / minsize
;
645 /* we need at least two URBs for queueing */
646 if (total_packs
< 2) {
649 /* and we don't want too long a queue either */
650 maxpacks
= max(MAX_QUEUE
* packs_per_ms
, urb_packs
* 2);
651 total_packs
= min(total_packs
, maxpacks
);
654 while (urb_packs
> 1 && urb_packs
* maxsize
>= period_bytes
)
656 total_packs
= MAX_URBS
* urb_packs
;
659 ep
->nurbs
= (total_packs
+ urb_packs
- 1) / urb_packs
;
660 if (ep
->nurbs
> MAX_URBS
) {
662 ep
->nurbs
= MAX_URBS
;
663 total_packs
= MAX_URBS
* urb_packs
;
664 } else if (ep
->nurbs
< 2) {
665 /* too little - we need at least two packets
666 * to ensure contiguous playback/capture
671 /* allocate and initialize data urbs */
672 for (i
= 0; i
< ep
->nurbs
; i
++) {
673 struct snd_urb_ctx
*u
= &ep
->urb
[i
];
676 u
->packets
= (i
+ 1) * total_packs
/ ep
->nurbs
677 - i
* total_packs
/ ep
->nurbs
;
678 u
->buffer_size
= maxsize
* u
->packets
;
680 if (fmt
->fmt_type
== UAC_FORMAT_TYPE_II
)
681 u
->packets
++; /* for transfer delimiter */
682 u
->urb
= usb_alloc_urb(u
->packets
, GFP_KERNEL
);
686 u
->urb
->transfer_buffer
=
687 usb_alloc_coherent(ep
->chip
->dev
, u
->buffer_size
,
688 GFP_KERNEL
, &u
->urb
->transfer_dma
);
689 if (!u
->urb
->transfer_buffer
)
691 u
->urb
->pipe
= ep
->pipe
;
692 u
->urb
->transfer_flags
= URB_ISO_ASAP
| URB_NO_TRANSFER_DMA_MAP
;
693 u
->urb
->interval
= 1 << ep
->datainterval
;
695 u
->urb
->complete
= snd_complete_urb
;
696 INIT_LIST_HEAD(&u
->ready_list
);
707 * configure a sync endpoint
709 static int sync_ep_set_params(struct snd_usb_endpoint
*ep
,
710 struct snd_pcm_hw_params
*hw_params
,
711 struct audioformat
*fmt
)
715 ep
->syncbuf
= usb_alloc_coherent(ep
->chip
->dev
, SYNC_URBS
* 4,
716 GFP_KERNEL
, &ep
->sync_dma
);
720 for (i
= 0; i
< SYNC_URBS
; i
++) {
721 struct snd_urb_ctx
*u
= &ep
->urb
[i
];
725 u
->urb
= usb_alloc_urb(1, GFP_KERNEL
);
728 u
->urb
->transfer_buffer
= ep
->syncbuf
+ i
* 4;
729 u
->urb
->transfer_dma
= ep
->sync_dma
+ i
* 4;
730 u
->urb
->transfer_buffer_length
= 4;
731 u
->urb
->pipe
= ep
->pipe
;
732 u
->urb
->transfer_flags
= URB_ISO_ASAP
|
733 URB_NO_TRANSFER_DMA_MAP
;
734 u
->urb
->number_of_packets
= 1;
735 u
->urb
->interval
= 1 << ep
->syncinterval
;
737 u
->urb
->complete
= snd_complete_urb
;
740 ep
->nurbs
= SYNC_URBS
;
750 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
752 * @ep: the snd_usb_endpoint to configure
753 * @hw_params: the hardware parameters
754 * @fmt: the USB audio format information
755 * @sync_ep: the sync endpoint to use, if any
757 * Determine the number of URBs to be used on this endpoint.
758 * An endpoint must be configured before it can be started.
759 * An endpoint that is already running can not be reconfigured.
761 int snd_usb_endpoint_set_params(struct snd_usb_endpoint
*ep
,
762 struct snd_pcm_hw_params
*hw_params
,
763 struct audioformat
*fmt
,
764 struct snd_usb_endpoint
*sync_ep
)
768 if (ep
->use_count
!= 0) {
769 snd_printk(KERN_WARNING
"Unable to change format on ep #%x: already in use\n",
774 /* release old buffers, if any */
777 ep
->datainterval
= fmt
->datainterval
;
778 ep
->maxpacksize
= fmt
->maxpacksize
;
779 ep
->fill_max
= !!(fmt
->attributes
& UAC_EP_CS_ATTR_FILL_MAX
);
781 if (snd_usb_get_speed(ep
->chip
->dev
) == USB_SPEED_FULL
)
782 ep
->freqn
= get_usb_full_speed_rate(params_rate(hw_params
));
784 ep
->freqn
= get_usb_high_speed_rate(params_rate(hw_params
));
786 /* calculate the frequency in 16.16 format */
787 ep
->freqm
= ep
->freqn
;
788 ep
->freqshift
= INT_MIN
;
793 case SND_USB_ENDPOINT_TYPE_DATA
:
794 err
= data_ep_set_params(ep
, hw_params
, fmt
, sync_ep
);
796 case SND_USB_ENDPOINT_TYPE_SYNC
:
797 err
= sync_ep_set_params(ep
, hw_params
, fmt
);
803 snd_printdd(KERN_DEBUG
"Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
804 ep
->ep_num
, ep
->type
, ep
->nurbs
, err
);
810 * snd_usb_endpoint_start: start an snd_usb_endpoint
812 * @ep: the endpoint to start
814 * A call to this function will increment the use count of the endpoint.
815 * In case it is not already running, the URBs for this endpoint will be
816 * submitted. Otherwise, this function does nothing.
818 * Must be balanced to calls of snd_usb_endpoint_stop().
820 * Returns an error if the URB submission failed, 0 in all other cases.
822 int snd_usb_endpoint_start(struct snd_usb_endpoint
*ep
)
827 if (ep
->chip
->shutdown
)
830 /* already running? */
831 if (++ep
->use_count
!= 1)
834 if (snd_BUG_ON(!test_bit(EP_FLAG_ACTIVATED
, &ep
->flags
)))
837 /* just to be sure */
838 deactivate_urbs(ep
, 0, 1);
846 * If this endpoint has a data endpoint as implicit feedback source,
847 * don't start the urbs here. Instead, mark them all as available,
848 * wait for the record urbs to return and queue the playback urbs
852 set_bit(EP_FLAG_RUNNING
, &ep
->flags
);
854 if (snd_usb_endpoint_implict_feedback_sink(ep
)) {
855 for (i
= 0; i
< ep
->nurbs
; i
++) {
856 struct snd_urb_ctx
*ctx
= ep
->urb
+ i
;
857 list_add_tail(&ctx
->ready_list
, &ep
->ready_playback_urbs
);
863 for (i
= 0; i
< ep
->nurbs
; i
++) {
864 struct urb
*urb
= ep
->urb
[i
].urb
;
866 if (snd_BUG_ON(!urb
))
869 if (usb_pipeout(ep
->pipe
)) {
870 prepare_outbound_urb_sizes(ep
, urb
->context
);
871 prepare_outbound_urb(ep
, urb
->context
);
873 prepare_inbound_urb(ep
, urb
->context
);
876 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
878 snd_printk(KERN_ERR
"cannot submit urb %d, error %d: %s\n",
879 i
, err
, usb_error_string(err
));
882 set_bit(i
, &ep
->active_mask
);
888 clear_bit(EP_FLAG_RUNNING
, &ep
->flags
);
890 deactivate_urbs(ep
, 0, 0);
895 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
897 * @ep: the endpoint to stop (may be NULL)
899 * A call to this function will decrement the use count of the endpoint.
900 * In case the last user has requested the endpoint stop, the URBs will
901 * actually be deactivated.
903 * Must be balanced to calls of snd_usb_endpoint_start().
905 void snd_usb_endpoint_stop(struct snd_usb_endpoint
*ep
,
906 int force
, int can_sleep
, int wait
)
911 if (snd_BUG_ON(ep
->use_count
== 0))
914 if (snd_BUG_ON(!test_bit(EP_FLAG_ACTIVATED
, &ep
->flags
)))
917 if (--ep
->use_count
== 0) {
918 deactivate_urbs(ep
, force
, can_sleep
);
919 ep
->data_subs
= NULL
;
920 ep
->sync_slave
= NULL
;
921 ep
->retire_data_urb
= NULL
;
922 ep
->prepare_data_urb
= NULL
;
930 * snd_usb_endpoint_activate: activate an snd_usb_endpoint
932 * @ep: the endpoint to activate
934 * If the endpoint is not currently in use, this functions will select the
935 * correct alternate interface setting for the interface of this endpoint.
937 * In case of any active users, this functions does nothing.
939 * Returns an error if usb_set_interface() failed, 0 in all other
942 int snd_usb_endpoint_activate(struct snd_usb_endpoint
*ep
)
944 if (ep
->use_count
!= 0)
947 if (!ep
->chip
->shutdown
&&
948 !test_and_set_bit(EP_FLAG_ACTIVATED
, &ep
->flags
)) {
951 ret
= usb_set_interface(ep
->chip
->dev
, ep
->iface
, ep
->alt_idx
);
953 snd_printk(KERN_ERR
"%s() usb_set_interface() failed, ret = %d\n",
955 clear_bit(EP_FLAG_ACTIVATED
, &ep
->flags
);
966 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
968 * @ep: the endpoint to deactivate
970 * If the endpoint is not currently in use, this functions will select the
971 * alternate interface setting 0 for the interface of this endpoint.
973 * In case of any active users, this functions does nothing.
975 * Returns an error if usb_set_interface() failed, 0 in all other
978 int snd_usb_endpoint_deactivate(struct snd_usb_endpoint
*ep
)
983 if (ep
->use_count
!= 0)
986 if (!ep
->chip
->shutdown
&&
987 test_and_clear_bit(EP_FLAG_ACTIVATED
, &ep
->flags
)) {
990 ret
= usb_set_interface(ep
->chip
->dev
, ep
->iface
, 0);
992 snd_printk(KERN_ERR
"%s(): usb_set_interface() failed, ret = %d\n",
1004 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1006 * @ep: the list header of the endpoint to free
1008 * This function does not care for the endpoint's use count but will tear
1009 * down all the streaming URBs immediately and free all resources.
1011 void snd_usb_endpoint_free(struct list_head
*head
)
1013 struct snd_usb_endpoint
*ep
;
1015 ep
= list_entry(head
, struct snd_usb_endpoint
, list
);
1016 release_urbs(ep
, 1);
1021 * snd_usb_handle_sync_urb: parse an USB sync packet
1023 * @ep: the endpoint to handle the packet
1024 * @sender: the sending endpoint
1025 * @urb: the received packet
1027 * This function is called from the context of an endpoint that received
1028 * the packet and is used to let another endpoint object handle the payload.
1030 void snd_usb_handle_sync_urb(struct snd_usb_endpoint
*ep
,
1031 struct snd_usb_endpoint
*sender
,
1032 const struct urb
*urb
)
1036 unsigned long flags
;
1038 snd_BUG_ON(ep
== sender
);
1041 * In case the endpoint is operating in implicit feedback mode, prepare
1042 * a new outbound URB that has the same layout as the received packet
1043 * and add it to the list of pending urbs. queue_pending_output_urbs()
1044 * will take care of them later.
1046 if (snd_usb_endpoint_implict_feedback_sink(ep
) &&
1047 ep
->use_count
!= 0) {
1049 /* implicit feedback case */
1051 struct snd_urb_ctx
*in_ctx
;
1052 struct snd_usb_packet_info
*out_packet
;
1054 in_ctx
= urb
->context
;
1056 /* Count overall packet size */
1057 for (i
= 0; i
< in_ctx
->packets
; i
++)
1058 if (urb
->iso_frame_desc
[i
].status
== 0)
1059 bytes
+= urb
->iso_frame_desc
[i
].actual_length
;
1062 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1063 * streaming once it received a 0-byte OUT URB
1068 spin_lock_irqsave(&ep
->lock
, flags
);
1069 out_packet
= ep
->next_packet
+ ep
->next_packet_write_pos
;
1072 * Iterate through the inbound packet and prepare the lengths
1073 * for the output packet. The OUT packet we are about to send
1074 * will have the same amount of payload bytes than the IN
1075 * packet we just received.
1078 out_packet
->packets
= in_ctx
->packets
;
1079 for (i
= 0; i
< in_ctx
->packets
; i
++) {
1080 if (urb
->iso_frame_desc
[i
].status
== 0)
1081 out_packet
->packet_size
[i
] =
1082 urb
->iso_frame_desc
[i
].actual_length
/ ep
->stride
;
1084 out_packet
->packet_size
[i
] = 0;
1087 ep
->next_packet_write_pos
++;
1088 ep
->next_packet_write_pos
%= MAX_URBS
;
1089 spin_unlock_irqrestore(&ep
->lock
, flags
);
1090 queue_pending_output_urbs(ep
);
1096 * process after playback sync complete
1098 * Full speed devices report feedback values in 10.14 format as samples
1099 * per frame, high speed devices in 16.16 format as samples per
1102 * Because the Audio Class 1 spec was written before USB 2.0, many high
1103 * speed devices use a wrong interpretation, some others use an
1104 * entirely different format.
1106 * Therefore, we cannot predict what format any particular device uses
1107 * and must detect it automatically.
1110 if (urb
->iso_frame_desc
[0].status
!= 0 ||
1111 urb
->iso_frame_desc
[0].actual_length
< 3)
1114 f
= le32_to_cpup(urb
->transfer_buffer
);
1115 if (urb
->iso_frame_desc
[0].actual_length
== 3)
1123 if (unlikely(ep
->freqshift
== INT_MIN
)) {
1125 * The first time we see a feedback value, determine its format
1126 * by shifting it left or right until it matches the nominal
1127 * frequency value. This assumes that the feedback does not
1128 * differ from the nominal value more than +50% or -25%.
1131 while (f
< ep
->freqn
- ep
->freqn
/ 4) {
1135 while (f
> ep
->freqn
+ ep
->freqn
/ 2) {
1139 ep
->freqshift
= shift
;
1140 } else if (ep
->freqshift
>= 0)
1141 f
<<= ep
->freqshift
;
1143 f
>>= -ep
->freqshift
;
1145 if (likely(f
>= ep
->freqn
- ep
->freqn
/ 8 && f
<= ep
->freqmax
)) {
1147 * If the frequency looks valid, set it.
1148 * This value is referred to in prepare_playback_urb().
1150 spin_lock_irqsave(&ep
->lock
, flags
);
1152 spin_unlock_irqrestore(&ep
->lock
, flags
);
1155 * Out of range; maybe the shift value is wrong.
1156 * Reset it so that we autodetect again the next time.
1158 ep
->freqshift
= INT_MIN
;