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path: root/drivers/usb/gadget/f_audio.c
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-rw-r--r--drivers/usb/gadget/f_audio.c707
1 files changed, 707 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_audio.c b/drivers/usb/gadget/f_audio.c
new file mode 100644
index 000000000000..66527ba2d2ea
--- /dev/null
+++ b/drivers/usb/gadget/f_audio.c
@@ -0,0 +1,707 @@
1/*
2 * f_audio.c -- USB Audio class function driver
3 *
4 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
5 * Copyright (C) 2008 Analog Devices, Inc
6 *
7 * Enter bugs at http://blackfin.uclinux.org/
8 *
9 * Licensed under the GPL-2 or later.
10 */
11
12#include <linux/kernel.h>
13#include <linux/device.h>
14#include <asm/atomic.h>
15
16#include "u_audio.h"
17
18#define OUT_EP_MAX_PACKET_SIZE 200
19static int req_buf_size = OUT_EP_MAX_PACKET_SIZE;
20module_param(req_buf_size, int, S_IRUGO);
21MODULE_PARM_DESC(req_buf_size, "ISO OUT endpoint request buffer size");
22
23static int req_count = 256;
24module_param(req_count, int, S_IRUGO);
25MODULE_PARM_DESC(req_count, "ISO OUT endpoint request count");
26
27static int audio_buf_size = 48000;
28module_param(audio_buf_size, int, S_IRUGO);
29MODULE_PARM_DESC(audio_buf_size, "Audio buffer size");
30
31/*
32 * DESCRIPTORS ... most are static, but strings and full
33 * configuration descriptors are built on demand.
34 */
35
36/*
37 * We have two interfaces- AudioControl and AudioStreaming
38 * TODO: only supcard playback currently
39 */
40#define F_AUDIO_AC_INTERFACE 0
41#define F_AUDIO_AS_INTERFACE 1
42#define F_AUDIO_NUM_INTERFACES 2
43
44/* B.3.1 Standard AC Interface Descriptor */
45static struct usb_interface_descriptor ac_interface_desc __initdata = {
46 .bLength = USB_DT_INTERFACE_SIZE,
47 .bDescriptorType = USB_DT_INTERFACE,
48 .bNumEndpoints = 0,
49 .bInterfaceClass = USB_CLASS_AUDIO,
50 .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
51};
52
53DECLARE_USB_AC_HEADER_DESCRIPTOR(2);
54
55#define USB_DT_AC_HEADER_LENGH USB_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
56/* B.3.2 Class-Specific AC Interface Descriptor */
57static struct usb_ac_header_descriptor_2 ac_header_desc = {
58 .bLength = USB_DT_AC_HEADER_LENGH,
59 .bDescriptorType = USB_DT_CS_INTERFACE,
60 .bDescriptorSubtype = HEADER,
61 .bcdADC = __constant_cpu_to_le16(0x0100),
62 .wTotalLength = __constant_cpu_to_le16(USB_DT_AC_HEADER_LENGH),
63 .bInCollection = F_AUDIO_NUM_INTERFACES,
64 .baInterfaceNr = {
65 [0] = F_AUDIO_AC_INTERFACE,
66 [1] = F_AUDIO_AS_INTERFACE,
67 }
68};
69
70#define INPUT_TERMINAL_ID 1
71static struct usb_input_terminal_descriptor input_terminal_desc = {
72 .bLength = USB_DT_AC_INPUT_TERMINAL_SIZE,
73 .bDescriptorType = USB_DT_CS_INTERFACE,
74 .bDescriptorSubtype = INPUT_TERMINAL,
75 .bTerminalID = INPUT_TERMINAL_ID,
76 .wTerminalType = USB_AC_TERMINAL_STREAMING,
77 .bAssocTerminal = 0,
78 .wChannelConfig = 0x3,
79};
80
81DECLARE_USB_AC_FEATURE_UNIT_DESCRIPTOR(0);
82
83#define FEATURE_UNIT_ID 2
84static struct usb_ac_feature_unit_descriptor_0 feature_unit_desc = {
85 .bLength = USB_DT_AC_FEATURE_UNIT_SIZE(0),
86 .bDescriptorType = USB_DT_CS_INTERFACE,
87 .bDescriptorSubtype = FEATURE_UNIT,
88 .bUnitID = FEATURE_UNIT_ID,
89 .bSourceID = INPUT_TERMINAL_ID,
90 .bControlSize = 2,
91 .bmaControls[0] = (FU_MUTE | FU_VOLUME),
92};
93
94static struct usb_audio_control mute_control = {
95 .list = LIST_HEAD_INIT(mute_control.list),
96 .name = "Mute Control",
97 .type = MUTE_CONTROL,
98 /* Todo: add real Mute control code */
99 .set = generic_set_cmd,
100 .get = generic_get_cmd,
101};
102
103static struct usb_audio_control volume_control = {
104 .list = LIST_HEAD_INIT(volume_control.list),
105 .name = "Volume Control",
106 .type = VOLUME_CONTROL,
107 /* Todo: add real Volume control code */
108 .set = generic_set_cmd,
109 .get = generic_get_cmd,
110};
111
112static struct usb_audio_control_selector feature_unit = {
113 .list = LIST_HEAD_INIT(feature_unit.list),
114 .id = FEATURE_UNIT_ID,
115 .name = "Mute & Volume Control",
116 .type = FEATURE_UNIT,
117 .desc = (struct usb_descriptor_header *)&feature_unit_desc,
118};
119
120#define OUTPUT_TERMINAL_ID 3
121static struct usb_output_terminal_descriptor output_terminal_desc = {
122 .bLength = USB_DT_AC_OUTPUT_TERMINAL_SIZE,
123 .bDescriptorType = USB_DT_CS_INTERFACE,
124 .bDescriptorSubtype = OUTPUT_TERMINAL,
125 .bTerminalID = OUTPUT_TERMINAL_ID,
126 .wTerminalType = USB_AC_OUTPUT_TERMINAL_SPEAKER,
127 .bAssocTerminal = FEATURE_UNIT_ID,
128 .bSourceID = FEATURE_UNIT_ID,
129};
130
131/* B.4.1 Standard AS Interface Descriptor */
132static struct usb_interface_descriptor as_interface_alt_0_desc = {
133 .bLength = USB_DT_INTERFACE_SIZE,
134 .bDescriptorType = USB_DT_INTERFACE,
135 .bAlternateSetting = 0,
136 .bNumEndpoints = 0,
137 .bInterfaceClass = USB_CLASS_AUDIO,
138 .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
139};
140
141static struct usb_interface_descriptor as_interface_alt_1_desc = {
142 .bLength = USB_DT_INTERFACE_SIZE,
143 .bDescriptorType = USB_DT_INTERFACE,
144 .bAlternateSetting = 1,
145 .bNumEndpoints = 1,
146 .bInterfaceClass = USB_CLASS_AUDIO,
147 .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
148};
149
150/* B.4.2 Class-Specific AS Interface Descriptor */
151static struct usb_as_header_descriptor as_header_desc = {
152 .bLength = USB_DT_AS_HEADER_SIZE,
153 .bDescriptorType = USB_DT_CS_INTERFACE,
154 .bDescriptorSubtype = AS_GENERAL,
155 .bTerminalLink = INPUT_TERMINAL_ID,
156 .bDelay = 1,
157 .wFormatTag = USB_AS_AUDIO_FORMAT_TYPE_I_PCM,
158};
159
160DECLARE_USB_AS_FORMAT_TYPE_I_DISCRETE_DESC(1);
161
162static struct usb_as_formate_type_i_discrete_descriptor_1 as_type_i_desc = {
163 .bLength = USB_AS_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
164 .bDescriptorType = USB_DT_CS_INTERFACE,
165 .bDescriptorSubtype = FORMAT_TYPE,
166 .bFormatType = USB_AS_FORMAT_TYPE_I,
167 .bSubframeSize = 2,
168 .bBitResolution = 16,
169 .bSamFreqType = 1,
170};
171
172/* Standard ISO OUT Endpoint Descriptor */
173static struct usb_endpoint_descriptor as_out_ep_desc __initdata = {
174 .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
175 .bDescriptorType = USB_DT_ENDPOINT,
176 .bEndpointAddress = USB_DIR_OUT,
177 .bmAttributes = USB_AS_ENDPOINT_ADAPTIVE
178 | USB_ENDPOINT_XFER_ISOC,
179 .wMaxPacketSize = __constant_cpu_to_le16(OUT_EP_MAX_PACKET_SIZE),
180 .bInterval = 4,
181};
182
183/* Class-specific AS ISO OUT Endpoint Descriptor */
184static struct usb_as_iso_endpoint_descriptor as_iso_out_desc __initdata = {
185 .bLength = USB_AS_ISO_ENDPOINT_DESC_SIZE,
186 .bDescriptorType = USB_DT_CS_ENDPOINT,
187 .bDescriptorSubtype = EP_GENERAL,
188 .bmAttributes = 1,
189 .bLockDelayUnits = 1,
190 .wLockDelay = __constant_cpu_to_le16(1),
191};
192
193static struct usb_descriptor_header *f_audio_desc[] __initdata = {
194 (struct usb_descriptor_header *)&ac_interface_desc,
195 (struct usb_descriptor_header *)&ac_header_desc,
196
197 (struct usb_descriptor_header *)&input_terminal_desc,
198 (struct usb_descriptor_header *)&output_terminal_desc,
199 (struct usb_descriptor_header *)&feature_unit_desc,
200
201 (struct usb_descriptor_header *)&as_interface_alt_0_desc,
202 (struct usb_descriptor_header *)&as_interface_alt_1_desc,
203 (struct usb_descriptor_header *)&as_header_desc,
204
205 (struct usb_descriptor_header *)&as_type_i_desc,
206
207 (struct usb_descriptor_header *)&as_out_ep_desc,
208 (struct usb_descriptor_header *)&as_iso_out_desc,
209 NULL,
210};
211
212/* string IDs are assigned dynamically */
213
214#define STRING_MANUFACTURER_IDX 0
215#define STRING_PRODUCT_IDX 1
216
217static char manufacturer[50];
218
219static struct usb_string strings_dev[] = {
220 [STRING_MANUFACTURER_IDX].s = manufacturer,
221 [STRING_PRODUCT_IDX].s = DRIVER_DESC,
222 { } /* end of list */
223};
224
225static struct usb_gadget_strings stringtab_dev = {
226 .language = 0x0409, /* en-us */
227 .strings = strings_dev,
228};
229
230static struct usb_gadget_strings *audio_strings[] = {
231 &stringtab_dev,
232 NULL,
233};
234
235/*
236 * This function is an ALSA sound card following USB Audio Class Spec 1.0.
237 */
238
239/*-------------------------------------------------------------------------*/
240struct f_audio_buf {
241 u8 *buf;
242 int actual;
243 struct list_head list;
244};
245
246static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
247{
248 struct f_audio_buf *copy_buf;
249
250 copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
251 if (!copy_buf)
252 return (struct f_audio_buf *)-ENOMEM;
253
254 copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
255 if (!copy_buf->buf) {
256 kfree(copy_buf);
257 return (struct f_audio_buf *)-ENOMEM;
258 }
259
260 return copy_buf;
261}
262
263static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
264{
265 kfree(audio_buf->buf);
266 kfree(audio_buf);
267}
268/*-------------------------------------------------------------------------*/
269
270struct f_audio {
271 struct gaudio card;
272
273 /* endpoints handle full and/or high speeds */
274 struct usb_ep *out_ep;
275 struct usb_endpoint_descriptor *out_desc;
276
277 spinlock_t lock;
278 struct f_audio_buf *copy_buf;
279 struct work_struct playback_work;
280 struct list_head play_queue;
281
282 /* Control Set command */
283 struct list_head cs;
284 u8 set_cmd;
285 struct usb_audio_control *set_con;
286};
287
288static inline struct f_audio *func_to_audio(struct usb_function *f)
289{
290 return container_of(f, struct f_audio, card.func);
291}
292
293/*-------------------------------------------------------------------------*/
294
295static void f_audio_playback_work(struct work_struct *data)
296{
297 struct f_audio *audio = container_of(data, struct f_audio,
298 playback_work);
299 struct f_audio_buf *play_buf;
300
301 spin_lock_irq(&audio->lock);
302 if (list_empty(&audio->play_queue)) {
303 spin_unlock_irq(&audio->lock);
304 return;
305 }
306 play_buf = list_first_entry(&audio->play_queue,
307 struct f_audio_buf, list);
308 list_del(&play_buf->list);
309 spin_unlock_irq(&audio->lock);
310
311 u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
312 f_audio_buffer_free(play_buf);
313
314 return;
315}
316
317static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
318{
319 struct f_audio *audio = req->context;
320 struct usb_composite_dev *cdev = audio->card.func.config->cdev;
321 struct f_audio_buf *copy_buf = audio->copy_buf;
322 int err;
323
324 if (!copy_buf)
325 return -EINVAL;
326
327 /* Copy buffer is full, add it to the play_queue */
328 if (audio_buf_size - copy_buf->actual < req->actual) {
329 list_add_tail(&copy_buf->list, &audio->play_queue);
330 schedule_work(&audio->playback_work);
331 copy_buf = f_audio_buffer_alloc(audio_buf_size);
332 if (copy_buf < 0)
333 return -ENOMEM;
334 }
335
336 memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
337 copy_buf->actual += req->actual;
338 audio->copy_buf = copy_buf;
339
340 err = usb_ep_queue(ep, req, GFP_ATOMIC);
341 if (err)
342 ERROR(cdev, "%s queue req: %d\n", ep->name, err);
343
344 return 0;
345
346}
347
348static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
349{
350 struct f_audio *audio = req->context;
351 int status = req->status;
352 u32 data = 0;
353 struct usb_ep *out_ep = audio->out_ep;
354
355 switch (status) {
356
357 case 0: /* normal completion? */
358 if (ep == out_ep)
359 f_audio_out_ep_complete(ep, req);
360 else if (audio->set_con) {
361 memcpy(&data, req->buf, req->length);
362 audio->set_con->set(audio->set_con, audio->set_cmd,
363 le16_to_cpu(data));
364 audio->set_con = NULL;
365 }
366 break;
367 default:
368 break;
369 }
370}
371
372static int audio_set_intf_req(struct usb_function *f,
373 const struct usb_ctrlrequest *ctrl)
374{
375 struct f_audio *audio = func_to_audio(f);
376 struct usb_composite_dev *cdev = f->config->cdev;
377 struct usb_request *req = cdev->req;
378 u8 id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
379 u16 len = le16_to_cpu(ctrl->wLength);
380 u16 w_value = le16_to_cpu(ctrl->wValue);
381 u8 con_sel = (w_value >> 8) & 0xFF;
382 u8 cmd = (ctrl->bRequest & 0x0F);
383 struct usb_audio_control_selector *cs;
384 struct usb_audio_control *con;
385
386 DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
387 ctrl->bRequest, w_value, len, id);
388
389 list_for_each_entry(cs, &audio->cs, list) {
390 if (cs->id == id) {
391 list_for_each_entry(con, &cs->control, list) {
392 if (con->type == con_sel) {
393 audio->set_con = con;
394 break;
395 }
396 }
397 break;
398 }
399 }
400
401 audio->set_cmd = cmd;
402 req->context = audio;
403 req->complete = f_audio_complete;
404
405 return len;
406}
407
408static int audio_get_intf_req(struct usb_function *f,
409 const struct usb_ctrlrequest *ctrl)
410{
411 struct f_audio *audio = func_to_audio(f);
412 struct usb_composite_dev *cdev = f->config->cdev;
413 struct usb_request *req = cdev->req;
414 int value = -EOPNOTSUPP;
415 u8 id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
416 u16 len = le16_to_cpu(ctrl->wLength);
417 u16 w_value = le16_to_cpu(ctrl->wValue);
418 u8 con_sel = (w_value >> 8) & 0xFF;
419 u8 cmd = (ctrl->bRequest & 0x0F);
420 struct usb_audio_control_selector *cs;
421 struct usb_audio_control *con;
422
423 DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
424 ctrl->bRequest, w_value, len, id);
425
426 list_for_each_entry(cs, &audio->cs, list) {
427 if (cs->id == id) {
428 list_for_each_entry(con, &cs->control, list) {
429 if (con->type == con_sel && con->get) {
430 value = con->get(con, cmd);
431 break;
432 }
433 }
434 break;
435 }
436 }
437
438 req->context = audio;
439 req->complete = f_audio_complete;
440 memcpy(req->buf, &value, len);
441
442 return len;
443}
444
445static int
446f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
447{
448 struct usb_composite_dev *cdev = f->config->cdev;
449 struct usb_request *req = cdev->req;
450 int value = -EOPNOTSUPP;
451 u16 w_index = le16_to_cpu(ctrl->wIndex);
452 u16 w_value = le16_to_cpu(ctrl->wValue);
453 u16 w_length = le16_to_cpu(ctrl->wLength);
454
455 /* composite driver infrastructure handles everything except
456 * Audio class messages; interface activation uses set_alt().
457 */
458 switch (ctrl->bRequestType) {
459 case USB_AUDIO_SET_INTF:
460 value = audio_set_intf_req(f, ctrl);
461 break;
462
463 case USB_AUDIO_GET_INTF:
464 value = audio_get_intf_req(f, ctrl);
465 break;
466
467 default:
468 ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
469 ctrl->bRequestType, ctrl->bRequest,
470 w_value, w_index, w_length);
471 }
472
473 /* respond with data transfer or status phase? */
474 if (value >= 0) {
475 DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
476 ctrl->bRequestType, ctrl->bRequest,
477 w_value, w_index, w_length);
478 req->zero = 0;
479 req->length = value;
480 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
481 if (value < 0)
482 ERROR(cdev, "audio response on err %d\n", value);
483 }
484
485 /* device either stalls (value < 0) or reports success */
486 return value;
487}
488
489static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
490{
491 struct f_audio *audio = func_to_audio(f);
492 struct usb_composite_dev *cdev = f->config->cdev;
493 struct usb_ep *out_ep = audio->out_ep;
494 struct usb_request *req;
495 int i = 0, err = 0;
496
497 DBG(cdev, "intf %d, alt %d\n", intf, alt);
498
499 if (intf == 1) {
500 if (alt == 1) {
501 usb_ep_enable(out_ep, audio->out_desc);
502 out_ep->driver_data = audio;
503 audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
504
505 /*
506 * allocate a bunch of read buffers
507 * and queue them all at once.
508 */
509 for (i = 0; i < req_count && err == 0; i++) {
510 req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
511 if (req) {
512 req->buf = kzalloc(req_buf_size,
513 GFP_ATOMIC);
514 if (req->buf) {
515 req->length = req_buf_size;
516 req->context = audio;
517 req->complete =
518 f_audio_complete;
519 err = usb_ep_queue(out_ep,
520 req, GFP_ATOMIC);
521 if (err)
522 ERROR(cdev,
523 "%s queue req: %d\n",
524 out_ep->name, err);
525 } else
526 err = -ENOMEM;
527 } else
528 err = -ENOMEM;
529 }
530
531 } else {
532 struct f_audio_buf *copy_buf = audio->copy_buf;
533 if (copy_buf) {
534 list_add_tail(&copy_buf->list,
535 &audio->play_queue);
536 schedule_work(&audio->playback_work);
537 }
538 }
539 }
540
541 return err;
542}
543
544static void f_audio_disable(struct usb_function *f)
545{
546 return;
547}
548
549/*-------------------------------------------------------------------------*/
550
551static void f_audio_build_desc(struct f_audio *audio)
552{
553 struct gaudio *card = &audio->card;
554 u8 *sam_freq;
555 int rate;
556
557 /* Set channel numbers */
558 input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
559 as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
560
561 /* Set sample rates */
562 rate = u_audio_get_playback_rate(card);
563 sam_freq = as_type_i_desc.tSamFreq[0];
564 memcpy(sam_freq, &rate, 3);
565
566 /* Todo: Set Sample bits and other parameters */
567
568 return;
569}
570
571/* audio function driver setup/binding */
572static int __init
573f_audio_bind(struct usb_configuration *c, struct usb_function *f)
574{
575 struct usb_composite_dev *cdev = c->cdev;
576 struct f_audio *audio = func_to_audio(f);
577 int status;
578 struct usb_ep *ep;
579
580 f_audio_build_desc(audio);
581
582 /* allocate instance-specific interface IDs, and patch descriptors */
583 status = usb_interface_id(c, f);
584 if (status < 0)
585 goto fail;
586 ac_interface_desc.bInterfaceNumber = status;
587
588 status = usb_interface_id(c, f);
589 if (status < 0)
590 goto fail;
591 as_interface_alt_0_desc.bInterfaceNumber = status;
592 as_interface_alt_1_desc.bInterfaceNumber = status;
593
594 status = -ENODEV;
595
596 /* allocate instance-specific endpoints */
597 ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
598 if (!ep)
599 goto fail;
600 audio->out_ep = ep;
601 ep->driver_data = cdev; /* claim */
602
603 status = -ENOMEM;
604
605 /* supcard all relevant hardware speeds... we expect that when
606 * hardware is dual speed, all bulk-capable endpoints work at
607 * both speeds
608 */
609
610 /* copy descriptors, and track endpoint copies */
611 if (gadget_is_dualspeed(c->cdev->gadget)) {
612 c->highspeed = true;
613 f->hs_descriptors = usb_copy_descriptors(f_audio_desc);
614 } else
615 f->descriptors = usb_copy_descriptors(f_audio_desc);
616
617 return 0;
618
619fail:
620
621 return status;
622}
623
624static void
625f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
626{
627 struct f_audio *audio = func_to_audio(f);
628
629 usb_free_descriptors(f->descriptors);
630 kfree(audio);
631}
632
633/*-------------------------------------------------------------------------*/
634
635/* Todo: add more control selecotor dynamically */
636int __init control_selector_init(struct f_audio *audio)
637{
638 INIT_LIST_HEAD(&audio->cs);
639 list_add(&feature_unit.list, &audio->cs);
640
641 INIT_LIST_HEAD(&feature_unit.control);
642 list_add(&mute_control.list, &feature_unit.control);
643 list_add(&volume_control.list, &feature_unit.control);
644
645 volume_control.data[_CUR] = 0xffc0;
646 volume_control.data[_MIN] = 0xe3a0;
647 volume_control.data[_MAX] = 0xfff0;
648 volume_control.data[_RES] = 0x0030;
649
650 return 0;
651}
652
653/**
654 * audio_bind_config - add USB audio fucntion to a configuration
655 * @c: the configuration to supcard the USB audio function
656 * Context: single threaded during gadget setup
657 *
658 * Returns zero on success, else negative errno.
659 */
660int __init audio_bind_config(struct usb_configuration *c)
661{
662 struct f_audio *audio;
663 int status;
664
665 /* allocate and initialize one new instance */
666 audio = kzalloc(sizeof *audio, GFP_KERNEL);
667 if (!audio)
668 return -ENOMEM;
669
670 audio->card.func.name = "g_audio";
671 audio->card.gadget = c->cdev->gadget;
672
673 INIT_LIST_HEAD(&audio->play_queue);
674 spin_lock_init(&audio->lock);
675
676 /* set up ASLA audio devices */
677 status = gaudio_setup(&audio->card);
678 if (status < 0)
679 goto setup_fail;
680
681 audio->card.func.strings = audio_strings;
682 audio->card.func.bind = f_audio_bind;
683 audio->card.func.unbind = f_audio_unbind;
684 audio->card.func.set_alt = f_audio_set_alt;
685 audio->card.func.setup = f_audio_setup;
686 audio->card.func.disable = f_audio_disable;
687 audio->out_desc = &as_out_ep_desc;
688
689 control_selector_init(audio);
690
691 INIT_WORK(&audio->playback_work, f_audio_playback_work);
692
693 status = usb_add_function(c, &audio->card.func);
694 if (status)
695 goto add_fail;
696
697 INFO(c->cdev, "audio_buf_size %d, req_buf_size %d, req_count %d\n",
698 audio_buf_size, req_buf_size, req_count);
699
700 return status;
701
702add_fail:
703 gaudio_cleanup(&audio->card);
704setup_fail:
705 kfree(audio);
706 return status;
707}
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-18 22:14:20 -0500