1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * f_audio.c -- USB Audio class function driver
4 *
5 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
6 * Copyright (C) 2008 Analog Devices, Inc
7 */
8
9#include <linux/slab.h>
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/device.h>
13#include <linux/atomic.h>
14
15#include "u_uac1_legacy.h"
16
17static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
18static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
19
20/*
21 * DESCRIPTORS ... most are static, but strings and full
22 * configuration descriptors are built on demand.
23 */
24
25/*
26 * We have two interfaces- AudioControl and AudioStreaming
27 * TODO: only supcard playback currently
28 */
29#define F_AUDIO_AC_INTERFACE 0
30#define F_AUDIO_AS_INTERFACE 1
31#define F_AUDIO_NUM_INTERFACES 1
32
33/* B.3.1 Standard AC Interface Descriptor */
34static struct usb_interface_descriptor ac_interface_desc = {
35 .bLength = USB_DT_INTERFACE_SIZE,
36 .bDescriptorType = USB_DT_INTERFACE,
37 .bNumEndpoints = 0,
38 .bInterfaceClass = USB_CLASS_AUDIO,
39 .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
40};
41
42/*
43 * The number of AudioStreaming and MIDIStreaming interfaces
44 * in the Audio Interface Collection
45 */
46DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
47
48#define UAC_DT_AC_HEADER_LENGTH UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
49/* 1 input terminal, 1 output terminal and 1 feature unit */
50#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
51 + UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
52/* B.3.2 Class-Specific AC Interface Descriptor */
53static struct uac1_ac_header_descriptor_1 ac_header_desc = {
54 .bLength = UAC_DT_AC_HEADER_LENGTH,
55 .bDescriptorType = USB_DT_CS_INTERFACE,
56 .bDescriptorSubtype = UAC_HEADER,
57 .bcdADC = cpu_to_le16(0x0100),
58 .wTotalLength = cpu_to_le16(UAC_DT_TOTAL_LENGTH),
59 .bInCollection = F_AUDIO_NUM_INTERFACES,
60 .baInterfaceNr = {
61 /* Interface number of the first AudioStream interface */
62 [0] = 1,
63 }
64};
65
66#define INPUT_TERMINAL_ID 1
67static struct uac_input_terminal_descriptor input_terminal_desc = {
68 .bLength = UAC_DT_INPUT_TERMINAL_SIZE,
69 .bDescriptorType = USB_DT_CS_INTERFACE,
70 .bDescriptorSubtype = UAC_INPUT_TERMINAL,
71 .bTerminalID = INPUT_TERMINAL_ID,
72 .wTerminalType = UAC_TERMINAL_STREAMING,
73 .bAssocTerminal = 0,
74 .wChannelConfig = 0x3,
75};
76
77DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
78
79#define FEATURE_UNIT_ID 2
80static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
81 .bLength = UAC_DT_FEATURE_UNIT_SIZE(0),
82 .bDescriptorType = USB_DT_CS_INTERFACE,
83 .bDescriptorSubtype = UAC_FEATURE_UNIT,
84 .bUnitID = FEATURE_UNIT_ID,
85 .bSourceID = INPUT_TERMINAL_ID,
86 .bControlSize = 2,
87 .bmaControls[0] = (UAC_FU_MUTE | UAC_FU_VOLUME),
88};
89
90static struct usb_audio_control mute_control = {
91 .list = LIST_HEAD_INIT(mute_control.list),
92 .name = "Mute Control",
93 .type = UAC_FU_MUTE,
94 /* Todo: add real Mute control code */
95 .set = generic_set_cmd,
96 .get = generic_get_cmd,
97};
98
99static struct usb_audio_control volume_control = {
100 .list = LIST_HEAD_INIT(volume_control.list),
101 .name = "Volume Control",
102 .type = UAC_FU_VOLUME,
103 /* Todo: add real Volume control code */
104 .set = generic_set_cmd,
105 .get = generic_get_cmd,
106};
107
108static struct usb_audio_control_selector feature_unit = {
109 .list = LIST_HEAD_INIT(feature_unit.list),
110 .id = FEATURE_UNIT_ID,
111 .name = "Mute & Volume Control",
112 .type = UAC_FEATURE_UNIT,
113 .desc = (struct usb_descriptor_header *)&feature_unit_desc,
114};
115
116#define OUTPUT_TERMINAL_ID 3
117static struct uac1_output_terminal_descriptor output_terminal_desc = {
118 .bLength = UAC_DT_OUTPUT_TERMINAL_SIZE,
119 .bDescriptorType = USB_DT_CS_INTERFACE,
120 .bDescriptorSubtype = UAC_OUTPUT_TERMINAL,
121 .bTerminalID = OUTPUT_TERMINAL_ID,
122 .wTerminalType = UAC_OUTPUT_TERMINAL_SPEAKER,
123 .bAssocTerminal = FEATURE_UNIT_ID,
124 .bSourceID = FEATURE_UNIT_ID,
125};
126
127/* B.4.1 Standard AS Interface Descriptor */
128static struct usb_interface_descriptor as_interface_alt_0_desc = {
129 .bLength = USB_DT_INTERFACE_SIZE,
130 .bDescriptorType = USB_DT_INTERFACE,
131 .bAlternateSetting = 0,
132 .bNumEndpoints = 0,
133 .bInterfaceClass = USB_CLASS_AUDIO,
134 .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
135};
136
137static struct usb_interface_descriptor as_interface_alt_1_desc = {
138 .bLength = USB_DT_INTERFACE_SIZE,
139 .bDescriptorType = USB_DT_INTERFACE,
140 .bAlternateSetting = 1,
141 .bNumEndpoints = 1,
142 .bInterfaceClass = USB_CLASS_AUDIO,
143 .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
144};
145
146/* B.4.2 Class-Specific AS Interface Descriptor */
147static struct uac1_as_header_descriptor as_header_desc = {
148 .bLength = UAC_DT_AS_HEADER_SIZE,
149 .bDescriptorType = USB_DT_CS_INTERFACE,
150 .bDescriptorSubtype = UAC_AS_GENERAL,
151 .bTerminalLink = INPUT_TERMINAL_ID,
152 .bDelay = 1,
153 .wFormatTag = UAC_FORMAT_TYPE_I_PCM,
154};
155
156DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
157
158static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
159 .bLength = UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
160 .bDescriptorType = USB_DT_CS_INTERFACE,
161 .bDescriptorSubtype = UAC_FORMAT_TYPE,
162 .bFormatType = UAC_FORMAT_TYPE_I,
163 .bSubframeSize = 2,
164 .bBitResolution = 16,
165 .bSamFreqType = 1,
166};
167
168/* Standard ISO OUT Endpoint Descriptor */
169static struct usb_endpoint_descriptor as_out_ep_desc = {
170 .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
171 .bDescriptorType = USB_DT_ENDPOINT,
172 .bEndpointAddress = USB_DIR_OUT,
173 .bmAttributes = USB_ENDPOINT_SYNC_ADAPTIVE
174 | USB_ENDPOINT_XFER_ISOC,
175 .wMaxPacketSize = cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
176 .bInterval = 4,
177};
178
179/* Class-specific AS ISO OUT Endpoint Descriptor */
180static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
181 .bLength = UAC_ISO_ENDPOINT_DESC_SIZE,
182 .bDescriptorType = USB_DT_CS_ENDPOINT,
183 .bDescriptorSubtype = UAC_EP_GENERAL,
184 .bmAttributes = 1,
185 .bLockDelayUnits = 1,
186 .wLockDelay = cpu_to_le16(1),
187};
188
189static struct usb_descriptor_header *f_audio_desc[] = {
190 (struct usb_descriptor_header *)&ac_interface_desc,
191 (struct usb_descriptor_header *)&ac_header_desc,
192
193 (struct usb_descriptor_header *)&input_terminal_desc,
194 (struct usb_descriptor_header *)&output_terminal_desc,
195 (struct usb_descriptor_header *)&feature_unit_desc,
196
197 (struct usb_descriptor_header *)&as_interface_alt_0_desc,
198 (struct usb_descriptor_header *)&as_interface_alt_1_desc,
199 (struct usb_descriptor_header *)&as_header_desc,
200
201 (struct usb_descriptor_header *)&as_type_i_desc,
202
203 (struct usb_descriptor_header *)&as_out_ep_desc,
204 (struct usb_descriptor_header *)&as_iso_out_desc,
205 NULL,
206};
207
208enum {
209 STR_AC_IF,
210 STR_INPUT_TERMINAL,
211 STR_INPUT_TERMINAL_CH_NAMES,
212 STR_FEAT_DESC_0,
213 STR_OUTPUT_TERMINAL,
214 STR_AS_IF_ALT0,
215 STR_AS_IF_ALT1,
216};
217
218static struct usb_string strings_uac1[] = {
219 [STR_AC_IF].s = "AC Interface",
220 [STR_INPUT_TERMINAL].s = "Input terminal",
221 [STR_INPUT_TERMINAL_CH_NAMES].s = "Channels",
222 [STR_FEAT_DESC_0].s = "Volume control & mute",
223 [STR_OUTPUT_TERMINAL].s = "Output terminal",
224 [STR_AS_IF_ALT0].s = "AS Interface",
225 [STR_AS_IF_ALT1].s = "AS Interface",
226 { },
227};
228
229static struct usb_gadget_strings str_uac1 = {
230 .language = 0x0409, /* en-us */
231 .strings = strings_uac1,
232};
233
234static struct usb_gadget_strings *uac1_strings[] = {
235 &str_uac1,
236 NULL,
237};
238
239/*
240 * This function is an ALSA sound card following USB Audio Class Spec 1.0.
241 */
242
243/*-------------------------------------------------------------------------*/
244struct f_audio_buf {
245 u8 *buf;
246 int actual;
247 struct list_head list;
248};
249
250static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
251{
252 struct f_audio_buf *copy_buf;
253
254 copy_buf = kzalloc(size: sizeof *copy_buf, GFP_ATOMIC);
255 if (!copy_buf)
256 return ERR_PTR(error: -ENOMEM);
257
258 copy_buf->buf = kzalloc(size: buf_size, GFP_ATOMIC);
259 if (!copy_buf->buf) {
260 kfree(objp: copy_buf);
261 return ERR_PTR(error: -ENOMEM);
262 }
263
264 return copy_buf;
265}
266
267static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
268{
269 kfree(objp: audio_buf->buf);
270 kfree(objp: audio_buf);
271}
272/*-------------------------------------------------------------------------*/
273
274struct f_audio {
275 struct gaudio card;
276
277 u8 ac_intf, ac_alt;
278 u8 as_intf, as_alt;
279
280 /* endpoints handle full and/or high speeds */
281 struct usb_ep *out_ep;
282
283 spinlock_t lock;
284 struct f_audio_buf *copy_buf;
285 struct work_struct playback_work;
286 struct list_head play_queue;
287
288 /* Control Set command */
289 struct list_head cs;
290 u8 set_cmd;
291 struct usb_audio_control *set_con;
292};
293
294static inline struct f_audio *func_to_audio(struct usb_function *f)
295{
296 return container_of(f, struct f_audio, card.func);
297}
298
299/*-------------------------------------------------------------------------*/
300
301static void f_audio_playback_work(struct work_struct *data)
302{
303 struct f_audio *audio = container_of(data, struct f_audio,
304 playback_work);
305 struct f_audio_buf *play_buf;
306
307 spin_lock_irq(lock: &audio->lock);
308 if (list_empty(head: &audio->play_queue)) {
309 spin_unlock_irq(lock: &audio->lock);
310 return;
311 }
312 play_buf = list_first_entry(&audio->play_queue,
313 struct f_audio_buf, list);
314 list_del(entry: &play_buf->list);
315 spin_unlock_irq(lock: &audio->lock);
316
317 u_audio_playback(card: &audio->card, buf: play_buf->buf, count: play_buf->actual);
318 f_audio_buffer_free(audio_buf: play_buf);
319}
320
321static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
322{
323 struct f_audio *audio = req->context;
324 struct usb_composite_dev *cdev = audio->card.func.config->cdev;
325 struct f_audio_buf *copy_buf = audio->copy_buf;
326 struct f_uac1_legacy_opts *opts;
327 int audio_buf_size;
328 int err;
329
330 opts = container_of(audio->card.func.fi, struct f_uac1_legacy_opts,
331 func_inst);
332 audio_buf_size = opts->audio_buf_size;
333
334 if (!copy_buf)
335 return -EINVAL;
336
337 /* Copy buffer is full, add it to the play_queue */
338 if (audio_buf_size - copy_buf->actual < req->actual) {
339 spin_lock_irq(lock: &audio->lock);
340 list_add_tail(new: &copy_buf->list, head: &audio->play_queue);
341 spin_unlock_irq(lock: &audio->lock);
342 schedule_work(work: &audio->playback_work);
343 copy_buf = f_audio_buffer_alloc(buf_size: audio_buf_size);
344 if (IS_ERR(ptr: copy_buf))
345 return -ENOMEM;
346 }
347
348 memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
349 copy_buf->actual += req->actual;
350 audio->copy_buf = copy_buf;
351
352 err = usb_ep_queue(ep, req, GFP_ATOMIC);
353 if (err)
354 ERROR(cdev, "%s queue req: %d\n", ep->name, err);
355
356 return 0;
357
358}
359
360static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
361{
362 struct f_audio *audio = req->context;
363 int status = req->status;
364 u32 data = 0;
365 struct usb_ep *out_ep = audio->out_ep;
366
367 switch (status) {
368
369 case 0: /* normal completion? */
370 if (ep == out_ep)
371 f_audio_out_ep_complete(ep, req);
372 else if (audio->set_con) {
373 memcpy(&data, req->buf, req->length);
374 audio->set_con->set(audio->set_con, audio->set_cmd,
375 le16_to_cpu(data));
376 audio->set_con = NULL;
377 }
378 break;
379 default:
380 break;
381 }
382}
383
384static int audio_set_intf_req(struct usb_function *f,
385 const struct usb_ctrlrequest *ctrl)
386{
387 struct f_audio *audio = func_to_audio(f);
388 struct usb_composite_dev *cdev = f->config->cdev;
389 struct usb_request *req = cdev->req;
390 u8 id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
391 u16 len = le16_to_cpu(ctrl->wLength);
392 u16 w_value = le16_to_cpu(ctrl->wValue);
393 u8 con_sel = (w_value >> 8) & 0xFF;
394 u8 cmd = (ctrl->bRequest & 0x0F);
395 struct usb_audio_control_selector *cs;
396 struct usb_audio_control *con;
397
398 DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
399 ctrl->bRequest, w_value, len, id);
400
401 list_for_each_entry(cs, &audio->cs, list) {
402 if (cs->id == id) {
403 list_for_each_entry(con, &cs->control, list) {
404 if (con->type == con_sel) {
405 audio->set_con = con;
406 break;
407 }
408 }
409 break;
410 }
411 }
412
413 audio->set_cmd = cmd;
414 req->context = audio;
415 req->complete = f_audio_complete;
416
417 return len;
418}
419
420static int audio_get_intf_req(struct usb_function *f,
421 const struct usb_ctrlrequest *ctrl)
422{
423 struct f_audio *audio = func_to_audio(f);
424 struct usb_composite_dev *cdev = f->config->cdev;
425 struct usb_request *req = cdev->req;
426 int value = -EOPNOTSUPP;
427 u8 id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
428 u16 len = le16_to_cpu(ctrl->wLength);
429 u16 w_value = le16_to_cpu(ctrl->wValue);
430 u8 con_sel = (w_value >> 8) & 0xFF;
431 u8 cmd = (ctrl->bRequest & 0x0F);
432 struct usb_audio_control_selector *cs;
433 struct usb_audio_control *con;
434
435 DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
436 ctrl->bRequest, w_value, len, id);
437
438 list_for_each_entry(cs, &audio->cs, list) {
439 if (cs->id == id) {
440 list_for_each_entry(con, &cs->control, list) {
441 if (con->type == con_sel && con->get) {
442 value = con->get(con, cmd);
443 break;
444 }
445 }
446 break;
447 }
448 }
449
450 req->context = audio;
451 req->complete = f_audio_complete;
452 len = min_t(size_t, sizeof(value), len);
453 memcpy(req->buf, &value, len);
454
455 return len;
456}
457
458static int audio_set_endpoint_req(struct usb_function *f,
459 const struct usb_ctrlrequest *ctrl)
460{
461 struct usb_composite_dev *cdev = f->config->cdev;
462 int value = -EOPNOTSUPP;
463 u16 ep = le16_to_cpu(ctrl->wIndex);
464 u16 len = le16_to_cpu(ctrl->wLength);
465 u16 w_value = le16_to_cpu(ctrl->wValue);
466
467 DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
468 ctrl->bRequest, w_value, len, ep);
469
470 switch (ctrl->bRequest) {
471 case UAC_SET_CUR:
472 value = len;
473 break;
474
475 case UAC_SET_MIN:
476 break;
477
478 case UAC_SET_MAX:
479 break;
480
481 case UAC_SET_RES:
482 break;
483
484 case UAC_SET_MEM:
485 break;
486
487 default:
488 break;
489 }
490
491 return value;
492}
493
494static int audio_get_endpoint_req(struct usb_function *f,
495 const struct usb_ctrlrequest *ctrl)
496{
497 struct usb_composite_dev *cdev = f->config->cdev;
498 int value = -EOPNOTSUPP;
499 u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
500 u16 len = le16_to_cpu(ctrl->wLength);
501 u16 w_value = le16_to_cpu(ctrl->wValue);
502
503 DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
504 ctrl->bRequest, w_value, len, ep);
505
506 switch (ctrl->bRequest) {
507 case UAC_GET_CUR:
508 case UAC_GET_MIN:
509 case UAC_GET_MAX:
510 case UAC_GET_RES:
511 value = len;
512 break;
513 case UAC_GET_MEM:
514 break;
515 default:
516 break;
517 }
518
519 return value;
520}
521
522static int
523f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
524{
525 struct usb_composite_dev *cdev = f->config->cdev;
526 struct usb_request *req = cdev->req;
527 int value = -EOPNOTSUPP;
528 u16 w_index = le16_to_cpu(ctrl->wIndex);
529 u16 w_value = le16_to_cpu(ctrl->wValue);
530 u16 w_length = le16_to_cpu(ctrl->wLength);
531
532 /* composite driver infrastructure handles everything; interface
533 * activation uses set_alt().
534 */
535 switch (ctrl->bRequestType) {
536 case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
537 value = audio_set_intf_req(f, ctrl);
538 break;
539
540 case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
541 value = audio_get_intf_req(f, ctrl);
542 break;
543
544 case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
545 value = audio_set_endpoint_req(f, ctrl);
546 break;
547
548 case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
549 value = audio_get_endpoint_req(f, ctrl);
550 break;
551
552 default:
553 ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
554 ctrl->bRequestType, ctrl->bRequest,
555 w_value, w_index, w_length);
556 }
557
558 /* respond with data transfer or status phase? */
559 if (value >= 0) {
560 DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
561 ctrl->bRequestType, ctrl->bRequest,
562 w_value, w_index, w_length);
563 req->zero = 0;
564 req->length = value;
565 value = usb_ep_queue(ep: cdev->gadget->ep0, req, GFP_ATOMIC);
566 if (value < 0)
567 ERROR(cdev, "audio response on err %d\n", value);
568 }
569
570 /* device either stalls (value < 0) or reports success */
571 return value;
572}
573
574static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
575{
576 struct f_audio *audio = func_to_audio(f);
577 struct usb_composite_dev *cdev = f->config->cdev;
578 struct usb_ep *out_ep = audio->out_ep;
579 struct usb_request *req;
580 struct f_uac1_legacy_opts *opts;
581 int req_buf_size, req_count, audio_buf_size;
582 int i = 0, err = 0;
583
584 DBG(cdev, "intf %d, alt %d\n", intf, alt);
585
586 opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
587 req_buf_size = opts->req_buf_size;
588 req_count = opts->req_count;
589 audio_buf_size = opts->audio_buf_size;
590
591 /* No i/f has more than 2 alt settings */
592 if (alt > 1) {
593 ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
594 return -EINVAL;
595 }
596
597 if (intf == audio->ac_intf) {
598 /* Control I/f has only 1 AltSetting - 0 */
599 if (alt) {
600 ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
601 return -EINVAL;
602 }
603 return 0;
604 } else if (intf == audio->as_intf) {
605 if (alt == 1) {
606 err = config_ep_by_speed(g: cdev->gadget, f, ep: out_ep);
607 if (err)
608 return err;
609
610 usb_ep_enable(ep: out_ep);
611 audio->copy_buf = f_audio_buffer_alloc(buf_size: audio_buf_size);
612 if (IS_ERR(ptr: audio->copy_buf))
613 return -ENOMEM;
614
615 /*
616 * allocate a bunch of read buffers
617 * and queue them all at once.
618 */
619 for (i = 0; i < req_count && err == 0; i++) {
620 req = usb_ep_alloc_request(ep: out_ep, GFP_ATOMIC);
621 if (req) {
622 req->buf = kzalloc(size: req_buf_size,
623 GFP_ATOMIC);
624 if (req->buf) {
625 req->length = req_buf_size;
626 req->context = audio;
627 req->complete =
628 f_audio_complete;
629 err = usb_ep_queue(ep: out_ep,
630 req, GFP_ATOMIC);
631 if (err)
632 ERROR(cdev,
633 "%s queue req: %d\n",
634 out_ep->name, err);
635 } else
636 err = -ENOMEM;
637 } else
638 err = -ENOMEM;
639 }
640
641 } else {
642 struct f_audio_buf *copy_buf = audio->copy_buf;
643 if (copy_buf) {
644 list_add_tail(new: &copy_buf->list,
645 head: &audio->play_queue);
646 schedule_work(work: &audio->playback_work);
647 }
648 }
649 audio->as_alt = alt;
650 }
651
652 return err;
653}
654
655static int f_audio_get_alt(struct usb_function *f, unsigned intf)
656{
657 struct f_audio *audio = func_to_audio(f);
658 struct usb_composite_dev *cdev = f->config->cdev;
659
660 if (intf == audio->ac_intf)
661 return audio->ac_alt;
662 else if (intf == audio->as_intf)
663 return audio->as_alt;
664 else
665 ERROR(cdev, "%s:%d Invalid Interface %d!\n",
666 __func__, __LINE__, intf);
667
668 return -EINVAL;
669}
670
671static void f_audio_disable(struct usb_function *f)
672{
673 return;
674}
675
676/*-------------------------------------------------------------------------*/
677
678static void f_audio_build_desc(struct f_audio *audio)
679{
680 struct gaudio *card = &audio->card;
681 u8 *sam_freq;
682 int rate;
683
684 /* Set channel numbers */
685 input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
686 as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
687
688 /* Set sample rates */
689 rate = u_audio_get_playback_rate(card);
690 sam_freq = as_type_i_desc.tSamFreq[0];
691 memcpy(sam_freq, &rate, 3);
692
693 /* Todo: Set Sample bits and other parameters */
694
695 return;
696}
697
698/* audio function driver setup/binding */
699static int
700f_audio_bind(struct usb_configuration *c, struct usb_function *f)
701{
702 struct usb_composite_dev *cdev = c->cdev;
703 struct f_audio *audio = func_to_audio(f);
704 struct usb_string *us;
705 int status;
706 struct usb_ep *ep = NULL;
707 struct f_uac1_legacy_opts *audio_opts;
708
709 audio_opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
710 audio->card.gadget = c->cdev->gadget;
711 /* set up ASLA audio devices */
712 if (!audio_opts->bound) {
713 status = gaudio_setup(card: &audio->card);
714 if (status < 0)
715 return status;
716 audio_opts->bound = true;
717 }
718 us = usb_gstrings_attach(cdev, sp: uac1_strings, ARRAY_SIZE(strings_uac1));
719 if (IS_ERR(ptr: us))
720 return PTR_ERR(ptr: us);
721 ac_interface_desc.iInterface = us[STR_AC_IF].id;
722 input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
723 input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
724 feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
725 output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
726 as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
727 as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
728
729
730 f_audio_build_desc(audio);
731
732 /* allocate instance-specific interface IDs, and patch descriptors */
733 status = usb_interface_id(c, f);
734 if (status < 0)
735 goto fail;
736 ac_interface_desc.bInterfaceNumber = status;
737 audio->ac_intf = status;
738 audio->ac_alt = 0;
739
740 status = usb_interface_id(c, f);
741 if (status < 0)
742 goto fail;
743 as_interface_alt_0_desc.bInterfaceNumber = status;
744 as_interface_alt_1_desc.bInterfaceNumber = status;
745 audio->as_intf = status;
746 audio->as_alt = 0;
747
748 status = -ENODEV;
749
750 /* allocate instance-specific endpoints */
751 ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
752 if (!ep)
753 goto fail;
754 audio->out_ep = ep;
755 audio->out_ep->desc = &as_out_ep_desc;
756
757 /* copy descriptors, and track endpoint copies */
758 status = usb_assign_descriptors(f, fs: f_audio_desc, hs: f_audio_desc, NULL,
759 NULL);
760 if (status)
761 goto fail;
762 return 0;
763
764fail:
765 gaudio_cleanup(the_card: &audio->card);
766 return status;
767}
768
769/*-------------------------------------------------------------------------*/
770
771static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
772{
773 con->data[cmd] = value;
774
775 return 0;
776}
777
778static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
779{
780 return con->data[cmd];
781}
782
783/* Todo: add more control selecotor dynamically */
784static int control_selector_init(struct f_audio *audio)
785{
786 INIT_LIST_HEAD(list: &audio->cs);
787 list_add(new: &feature_unit.list, head: &audio->cs);
788
789 INIT_LIST_HEAD(list: &feature_unit.control);
790 list_add(new: &mute_control.list, head: &feature_unit.control);
791 list_add(new: &volume_control.list, head: &feature_unit.control);
792
793 volume_control.data[UAC__CUR] = 0xffc0;
794 volume_control.data[UAC__MIN] = 0xe3a0;
795 volume_control.data[UAC__MAX] = 0xfff0;
796 volume_control.data[UAC__RES] = 0x0030;
797
798 return 0;
799}
800
801static inline
802struct f_uac1_legacy_opts *to_f_uac1_opts(struct config_item *item)
803{
804 return container_of(to_config_group(item), struct f_uac1_legacy_opts,
805 func_inst.group);
806}
807
808static void f_uac1_attr_release(struct config_item *item)
809{
810 struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);
811
812 usb_put_function_instance(fi: &opts->func_inst);
813}
814
815static struct configfs_item_operations f_uac1_item_ops = {
816 .release = f_uac1_attr_release,
817};
818
819#define UAC1_INT_ATTRIBUTE(name) \
820static ssize_t f_uac1_opts_##name##_show(struct config_item *item, \
821 char *page) \
822{ \
823 struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item); \
824 int result; \
825 \
826 mutex_lock(&opts->lock); \
827 result = sprintf(page, "%u\n", opts->name); \
828 mutex_unlock(&opts->lock); \
829 \
830 return result; \
831} \
832 \
833static ssize_t f_uac1_opts_##name##_store(struct config_item *item, \
834 const char *page, size_t len) \
835{ \
836 struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item); \
837 int ret; \
838 u32 num; \
839 \
840 mutex_lock(&opts->lock); \
841 if (opts->refcnt) { \
842 ret = -EBUSY; \
843 goto end; \
844 } \
845 \
846 ret = kstrtou32(page, 0, &num); \
847 if (ret) \
848 goto end; \
849 \
850 opts->name = num; \
851 ret = len; \
852 \
853end: \
854 mutex_unlock(&opts->lock); \
855 return ret; \
856} \
857 \
858CONFIGFS_ATTR(f_uac1_opts_, name)
859
860UAC1_INT_ATTRIBUTE(req_buf_size);
861UAC1_INT_ATTRIBUTE(req_count);
862UAC1_INT_ATTRIBUTE(audio_buf_size);
863
864#define UAC1_STR_ATTRIBUTE(name) \
865static ssize_t f_uac1_opts_##name##_show(struct config_item *item, \
866 char *page) \
867{ \
868 struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item); \
869 int result; \
870 \
871 mutex_lock(&opts->lock); \
872 result = sprintf(page, "%s\n", opts->name); \
873 mutex_unlock(&opts->lock); \
874 \
875 return result; \
876} \
877 \
878static ssize_t f_uac1_opts_##name##_store(struct config_item *item, \
879 const char *page, size_t len) \
880{ \
881 struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item); \
882 int ret = -EBUSY; \
883 char *tmp; \
884 \
885 mutex_lock(&opts->lock); \
886 if (opts->refcnt) \
887 goto end; \
888 \
889 tmp = kstrndup(page, len, GFP_KERNEL); \
890 if (tmp) { \
891 ret = -ENOMEM; \
892 goto end; \
893 } \
894 if (opts->name##_alloc) \
895 kfree(opts->name); \
896 opts->name##_alloc = true; \
897 opts->name = tmp; \
898 ret = len; \
899 \
900end: \
901 mutex_unlock(&opts->lock); \
902 return ret; \
903} \
904 \
905CONFIGFS_ATTR(f_uac1_opts_, name)
906
907UAC1_STR_ATTRIBUTE(fn_play);
908UAC1_STR_ATTRIBUTE(fn_cap);
909UAC1_STR_ATTRIBUTE(fn_cntl);
910
911static struct configfs_attribute *f_uac1_attrs[] = {
912 &f_uac1_opts_attr_req_buf_size,
913 &f_uac1_opts_attr_req_count,
914 &f_uac1_opts_attr_audio_buf_size,
915 &f_uac1_opts_attr_fn_play,
916 &f_uac1_opts_attr_fn_cap,
917 &f_uac1_opts_attr_fn_cntl,
918 NULL,
919};
920
921static const struct config_item_type f_uac1_func_type = {
922 .ct_item_ops = &f_uac1_item_ops,
923 .ct_attrs = f_uac1_attrs,
924 .ct_owner = THIS_MODULE,
925};
926
927static void f_audio_free_inst(struct usb_function_instance *f)
928{
929 struct f_uac1_legacy_opts *opts;
930
931 opts = container_of(f, struct f_uac1_legacy_opts, func_inst);
932 if (opts->fn_play_alloc)
933 kfree(objp: opts->fn_play);
934 if (opts->fn_cap_alloc)
935 kfree(objp: opts->fn_cap);
936 if (opts->fn_cntl_alloc)
937 kfree(objp: opts->fn_cntl);
938 kfree(objp: opts);
939}
940
941static struct usb_function_instance *f_audio_alloc_inst(void)
942{
943 struct f_uac1_legacy_opts *opts;
944
945 opts = kzalloc(size: sizeof(*opts), GFP_KERNEL);
946 if (!opts)
947 return ERR_PTR(error: -ENOMEM);
948
949 mutex_init(&opts->lock);
950 opts->func_inst.free_func_inst = f_audio_free_inst;
951
952 config_group_init_type_name(group: &opts->func_inst.group, name: "",
953 type: &f_uac1_func_type);
954
955 opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
956 opts->req_count = UAC1_REQ_COUNT;
957 opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
958 opts->fn_play = FILE_PCM_PLAYBACK;
959 opts->fn_cap = FILE_PCM_CAPTURE;
960 opts->fn_cntl = FILE_CONTROL;
961 return &opts->func_inst;
962}
963
964static void f_audio_free(struct usb_function *f)
965{
966 struct f_audio *audio = func_to_audio(f);
967 struct f_uac1_legacy_opts *opts;
968
969 gaudio_cleanup(the_card: &audio->card);
970 opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
971 kfree(objp: audio);
972 mutex_lock(&opts->lock);
973 --opts->refcnt;
974 mutex_unlock(lock: &opts->lock);
975}
976
977static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
978{
979 usb_free_all_descriptors(f);
980}
981
982static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
983{
984 struct f_audio *audio;
985 struct f_uac1_legacy_opts *opts;
986
987 /* allocate and initialize one new instance */
988 audio = kzalloc(size: sizeof(*audio), GFP_KERNEL);
989 if (!audio)
990 return ERR_PTR(error: -ENOMEM);
991
992 audio->card.func.name = "g_audio";
993
994 opts = container_of(fi, struct f_uac1_legacy_opts, func_inst);
995 mutex_lock(&opts->lock);
996 ++opts->refcnt;
997 mutex_unlock(lock: &opts->lock);
998 INIT_LIST_HEAD(list: &audio->play_queue);
999 spin_lock_init(&audio->lock);
1000
1001 audio->card.func.bind = f_audio_bind;
1002 audio->card.func.unbind = f_audio_unbind;
1003 audio->card.func.set_alt = f_audio_set_alt;
1004 audio->card.func.get_alt = f_audio_get_alt;
1005 audio->card.func.setup = f_audio_setup;
1006 audio->card.func.disable = f_audio_disable;
1007 audio->card.func.free_func = f_audio_free;
1008
1009 control_selector_init(audio);
1010
1011 INIT_WORK(&audio->playback_work, f_audio_playback_work);
1012
1013 return &audio->card.func;
1014}
1015
1016DECLARE_USB_FUNCTION_INIT(uac1_legacy, f_audio_alloc_inst, f_audio_alloc);
1017MODULE_LICENSE("GPL");
1018MODULE_AUTHOR("Bryan Wu");
1019

source code of linux/drivers/usb/gadget/function/f_uac1_legacy.c