1// SPDX-License-Identifier: GPL-2.0+
2//
3// Empiatech em28x1 audio extension
4//
5// Copyright (C) 2006 Markus Rechberger <mrechberger@gmail.com>
6//
7// Copyright (C) 2007-2016 Mauro Carvalho Chehab
8// - Port to work with the in-kernel driver
9// - Cleanups, fixes, alsa-controls, etc.
10//
11// This driver is based on my previous au600 usb pstn audio driver
12// and inherits all the copyrights
13
14#include "em28xx.h"
15
16#include <linux/kernel.h>
17#include <linux/usb.h>
18#include <linux/init.h>
19#include <linux/sound.h>
20#include <linux/spinlock.h>
21#include <linux/soundcard.h>
22#include <linux/slab.h>
23#include <linux/module.h>
24#include <sound/core.h>
25#include <sound/pcm.h>
26#include <sound/pcm_params.h>
27#include <sound/info.h>
28#include <sound/initval.h>
29#include <sound/control.h>
30#include <sound/tlv.h>
31#include <sound/ac97_codec.h>
32#include <media/v4l2-common.h>
33
34static int debug;
35module_param(debug, int, 0644);
36MODULE_PARM_DESC(debug, "activates debug info");
37
38#define EM28XX_MAX_AUDIO_BUFS 5
39#define EM28XX_MIN_AUDIO_PACKETS 64
40
41#define dprintk(fmt, arg...) do { \
42 if (debug) \
43 dev_printk(KERN_DEBUG, &dev->intf->dev, \
44 "video: %s: " fmt, __func__, ## arg); \
45} while (0)
46
47static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
48
49static int em28xx_deinit_isoc_audio(struct em28xx *dev)
50{
51 int i;
52
53 dprintk("Stopping isoc\n");
54 for (i = 0; i < dev->adev.num_urb; i++) {
55 struct urb *urb = dev->adev.urb[i];
56
57 if (!irqs_disabled())
58 usb_kill_urb(urb);
59 else
60 usb_unlink_urb(urb);
61 }
62
63 return 0;
64}
65
66static void em28xx_audio_isocirq(struct urb *urb)
67{
68 struct em28xx *dev = urb->context;
69 int i;
70 unsigned int oldptr;
71 int period_elapsed = 0;
72 int status;
73 unsigned char *cp;
74 unsigned int stride;
75 struct snd_pcm_substream *substream;
76 struct snd_pcm_runtime *runtime;
77
78 if (dev->disconnected) {
79 dprintk("device disconnected while streaming. URB status=%d.\n",
80 urb->status);
81 atomic_set(v: &dev->adev.stream_started, i: 0);
82 return;
83 }
84
85 switch (urb->status) {
86 case 0: /* success */
87 case -ETIMEDOUT: /* NAK */
88 break;
89 case -ECONNRESET: /* kill */
90 case -ENOENT:
91 case -ESHUTDOWN:
92 return;
93 default: /* error */
94 dprintk("urb completion error %d.\n", urb->status);
95 break;
96 }
97
98 if (atomic_read(v: &dev->adev.stream_started) == 0)
99 return;
100
101 if (dev->adev.capture_pcm_substream) {
102 substream = dev->adev.capture_pcm_substream;
103 runtime = substream->runtime;
104 stride = runtime->frame_bits >> 3;
105
106 for (i = 0; i < urb->number_of_packets; i++) {
107 unsigned long flags;
108 int length =
109 urb->iso_frame_desc[i].actual_length / stride;
110 cp = (unsigned char *)urb->transfer_buffer +
111 urb->iso_frame_desc[i].offset;
112
113 if (!length)
114 continue;
115
116 oldptr = dev->adev.hwptr_done_capture;
117 if (oldptr + length >= runtime->buffer_size) {
118 unsigned int cnt =
119 runtime->buffer_size - oldptr;
120 memcpy(runtime->dma_area + oldptr * stride, cp,
121 cnt * stride);
122 memcpy(runtime->dma_area, cp + cnt * stride,
123 length * stride - cnt * stride);
124 } else {
125 memcpy(runtime->dma_area + oldptr * stride, cp,
126 length * stride);
127 }
128
129 snd_pcm_stream_lock_irqsave(substream, flags);
130
131 dev->adev.hwptr_done_capture += length;
132 if (dev->adev.hwptr_done_capture >=
133 runtime->buffer_size)
134 dev->adev.hwptr_done_capture -=
135 runtime->buffer_size;
136
137 dev->adev.capture_transfer_done += length;
138 if (dev->adev.capture_transfer_done >=
139 runtime->period_size) {
140 dev->adev.capture_transfer_done -=
141 runtime->period_size;
142 period_elapsed = 1;
143 }
144
145 snd_pcm_stream_unlock_irqrestore(substream, flags);
146 }
147 if (period_elapsed)
148 snd_pcm_period_elapsed(substream);
149 }
150 urb->status = 0;
151
152 status = usb_submit_urb(urb, GFP_ATOMIC);
153 if (status < 0)
154 dev_err(&dev->intf->dev,
155 "resubmit of audio urb failed (error=%i)\n",
156 status);
157}
158
159static int em28xx_init_audio_isoc(struct em28xx *dev)
160{
161 int i, err;
162
163 dprintk("Starting isoc transfers\n");
164
165 /* Start streaming */
166 for (i = 0; i < dev->adev.num_urb; i++) {
167 memset(dev->adev.transfer_buffer[i], 0x80,
168 dev->adev.urb[i]->transfer_buffer_length);
169
170 err = usb_submit_urb(urb: dev->adev.urb[i], GFP_ATOMIC);
171 if (err) {
172 dev_err(&dev->intf->dev,
173 "submit of audio urb failed (error=%i)\n",
174 err);
175 em28xx_deinit_isoc_audio(dev);
176 atomic_set(v: &dev->adev.stream_started, i: 0);
177 return err;
178 }
179 }
180
181 return 0;
182}
183
184static const struct snd_pcm_hardware snd_em28xx_hw_capture = {
185 .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
186 SNDRV_PCM_INFO_MMAP |
187 SNDRV_PCM_INFO_INTERLEAVED |
188 SNDRV_PCM_INFO_BATCH |
189 SNDRV_PCM_INFO_MMAP_VALID,
190
191 .formats = SNDRV_PCM_FMTBIT_S16_LE,
192
193 .rates = SNDRV_PCM_RATE_48000,
194
195 .rate_min = 48000,
196 .rate_max = 48000,
197 .channels_min = 2,
198 .channels_max = 2,
199 .buffer_bytes_max = 62720 * 8, /* just about the value in usbaudio.c */
200
201 /*
202 * The period is 12.288 bytes. Allow a 10% of variation along its
203 * value, in order to avoid overruns/underruns due to some clock
204 * drift.
205 *
206 * FIXME: This period assumes 64 packets, and a 48000 PCM rate.
207 * Calculate it dynamically.
208 */
209 .period_bytes_min = 11059,
210 .period_bytes_max = 13516,
211
212 .periods_min = 2,
213 .periods_max = 98, /* 12544, */
214};
215
216static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
217{
218 struct em28xx *dev = snd_pcm_substream_chip(substream);
219 struct snd_pcm_runtime *runtime = substream->runtime;
220 int nonblock, ret = 0;
221
222 if (!dev) {
223 pr_err("em28xx-audio: BUG: em28xx can't find device struct. Can't proceed with open\n");
224 return -ENODEV;
225 }
226
227 if (dev->disconnected)
228 return -ENODEV;
229
230 dprintk("opening device and trying to acquire exclusive lock\n");
231
232 nonblock = !!(substream->f_flags & O_NONBLOCK);
233 if (nonblock) {
234 if (!mutex_trylock(lock: &dev->lock))
235 return -EAGAIN;
236 } else {
237 mutex_lock(&dev->lock);
238 }
239
240 runtime->hw = snd_em28xx_hw_capture;
241
242 if (dev->adev.users == 0) {
243 if (!dev->alt || dev->is_audio_only) {
244 struct usb_device *udev;
245
246 udev = interface_to_usbdev(dev->intf);
247
248 if (dev->is_audio_only)
249 /* audio is on a separate interface */
250 dev->alt = 1;
251 else
252 /* audio is on the same interface as video */
253 dev->alt = 7;
254 /*
255 * FIXME: The intention seems to be to select
256 * the alt setting with the largest
257 * wMaxPacketSize for the video endpoint.
258 * At least dev->alt should be used instead, but
259 * we should probably not touch it at all if it
260 * is already >0, because wMaxPacketSize of the
261 * audio endpoints seems to be the same for all.
262 */
263 dprintk("changing alternate number on interface %d to %d\n",
264 dev->ifnum, dev->alt);
265 usb_set_interface(dev: udev, ifnum: dev->ifnum, alternate: dev->alt);
266 }
267
268 /* Sets volume, mute, etc */
269 dev->mute = 0;
270 ret = em28xx_audio_analog_set(dev);
271 if (ret < 0)
272 goto err;
273 }
274
275 kref_get(kref: &dev->ref);
276 dev->adev.users++;
277 mutex_unlock(lock: &dev->lock);
278
279 /* Dynamically adjust the period size */
280 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
281 snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
282 min: dev->adev.period * 95 / 100,
283 max: dev->adev.period * 105 / 100);
284
285 dev->adev.capture_pcm_substream = substream;
286
287 return 0;
288err:
289 mutex_unlock(lock: &dev->lock);
290
291 dev_err(&dev->intf->dev,
292 "Error while configuring em28xx mixer\n");
293 return ret;
294}
295
296static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
297{
298 struct em28xx *dev = snd_pcm_substream_chip(substream);
299
300 dprintk("closing device\n");
301
302 dev->mute = 1;
303 mutex_lock(&dev->lock);
304 dev->adev.users--;
305 if (atomic_read(v: &dev->adev.stream_started) > 0) {
306 atomic_set(v: &dev->adev.stream_started, i: 0);
307 schedule_work(work: &dev->adev.wq_trigger);
308 }
309
310 em28xx_audio_analog_set(dev);
311 mutex_unlock(lock: &dev->lock);
312 kref_put(kref: &dev->ref, release: em28xx_free_device);
313
314 return 0;
315}
316
317static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
318{
319 struct em28xx *dev = snd_pcm_substream_chip(substream);
320
321 if (dev->disconnected)
322 return -ENODEV;
323
324 dev->adev.hwptr_done_capture = 0;
325 dev->adev.capture_transfer_done = 0;
326
327 return 0;
328}
329
330static void audio_trigger(struct work_struct *work)
331{
332 struct em28xx_audio *adev =
333 container_of(work, struct em28xx_audio, wq_trigger);
334 struct em28xx *dev = container_of(adev, struct em28xx, adev);
335
336 if (atomic_read(v: &adev->stream_started)) {
337 dprintk("starting capture");
338 em28xx_init_audio_isoc(dev);
339 } else {
340 dprintk("stopping capture");
341 em28xx_deinit_isoc_audio(dev);
342 }
343}
344
345static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
346 int cmd)
347{
348 struct em28xx *dev = snd_pcm_substream_chip(substream);
349 int retval = 0;
350
351 if (dev->disconnected)
352 return -ENODEV;
353
354 switch (cmd) {
355 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
356 case SNDRV_PCM_TRIGGER_RESUME:
357 case SNDRV_PCM_TRIGGER_START:
358 atomic_set(v: &dev->adev.stream_started, i: 1);
359 break;
360 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
361 case SNDRV_PCM_TRIGGER_SUSPEND:
362 case SNDRV_PCM_TRIGGER_STOP:
363 atomic_set(v: &dev->adev.stream_started, i: 0);
364 break;
365 default:
366 retval = -EINVAL;
367 }
368 schedule_work(work: &dev->adev.wq_trigger);
369 return retval;
370}
371
372static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
373 *substream)
374{
375 unsigned long flags;
376 struct em28xx *dev;
377 snd_pcm_uframes_t hwptr_done;
378
379 dev = snd_pcm_substream_chip(substream);
380 if (dev->disconnected)
381 return SNDRV_PCM_POS_XRUN;
382
383 spin_lock_irqsave(&dev->adev.slock, flags);
384 hwptr_done = dev->adev.hwptr_done_capture;
385 spin_unlock_irqrestore(lock: &dev->adev.slock, flags);
386
387 return hwptr_done;
388}
389
390/*
391 * AC97 volume control support
392 */
393static int em28xx_vol_info(struct snd_kcontrol *kcontrol,
394 struct snd_ctl_elem_info *info)
395{
396 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
397
398 if (dev->disconnected)
399 return -ENODEV;
400
401 info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
402 info->count = 2;
403 info->value.integer.min = 0;
404 info->value.integer.max = 0x1f;
405
406 return 0;
407}
408
409static int em28xx_vol_put(struct snd_kcontrol *kcontrol,
410 struct snd_ctl_elem_value *value)
411{
412 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
413 struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
414 u16 val = (0x1f - (value->value.integer.value[0] & 0x1f)) |
415 (0x1f - (value->value.integer.value[1] & 0x1f)) << 8;
416 int nonblock = 0;
417 int rc;
418
419 if (dev->disconnected)
420 return -ENODEV;
421
422 if (substream)
423 nonblock = !!(substream->f_flags & O_NONBLOCK);
424 if (nonblock) {
425 if (!mutex_trylock(lock: &dev->lock))
426 return -EAGAIN;
427 } else {
428 mutex_lock(&dev->lock);
429 }
430 rc = em28xx_read_ac97(dev, reg: kcontrol->private_value);
431 if (rc < 0)
432 goto err;
433
434 val |= rc & 0x8000; /* Preserve the mute flag */
435
436 rc = em28xx_write_ac97(dev, reg: kcontrol->private_value, val);
437 if (rc < 0)
438 goto err;
439
440 dprintk("%sleft vol %d, right vol %d (0x%04x) to ac97 volume control 0x%04x\n",
441 (val & 0x8000) ? "muted " : "",
442 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
443 val, (int)kcontrol->private_value);
444
445err:
446 mutex_unlock(lock: &dev->lock);
447 return rc;
448}
449
450static int em28xx_vol_get(struct snd_kcontrol *kcontrol,
451 struct snd_ctl_elem_value *value)
452{
453 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
454 struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
455 int nonblock = 0;
456 int val;
457
458 if (dev->disconnected)
459 return -ENODEV;
460
461 if (substream)
462 nonblock = !!(substream->f_flags & O_NONBLOCK);
463 if (nonblock) {
464 if (!mutex_trylock(lock: &dev->lock))
465 return -EAGAIN;
466 } else {
467 mutex_lock(&dev->lock);
468 }
469 val = em28xx_read_ac97(dev, reg: kcontrol->private_value);
470 mutex_unlock(lock: &dev->lock);
471 if (val < 0)
472 return val;
473
474 dprintk("%sleft vol %d, right vol %d (0x%04x) from ac97 volume control 0x%04x\n",
475 (val & 0x8000) ? "muted " : "",
476 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
477 val, (int)kcontrol->private_value);
478
479 value->value.integer.value[0] = 0x1f - (val & 0x1f);
480 value->value.integer.value[1] = 0x1f - ((val >> 8) & 0x1f);
481
482 return 0;
483}
484
485static int em28xx_vol_put_mute(struct snd_kcontrol *kcontrol,
486 struct snd_ctl_elem_value *value)
487{
488 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
489 u16 val = value->value.integer.value[0];
490 struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
491 int nonblock = 0;
492 int rc;
493
494 if (dev->disconnected)
495 return -ENODEV;
496
497 if (substream)
498 nonblock = !!(substream->f_flags & O_NONBLOCK);
499 if (nonblock) {
500 if (!mutex_trylock(lock: &dev->lock))
501 return -EAGAIN;
502 } else {
503 mutex_lock(&dev->lock);
504 }
505 rc = em28xx_read_ac97(dev, reg: kcontrol->private_value);
506 if (rc < 0)
507 goto err;
508
509 if (val)
510 rc &= 0x1f1f;
511 else
512 rc |= 0x8000;
513
514 rc = em28xx_write_ac97(dev, reg: kcontrol->private_value, val: rc);
515 if (rc < 0)
516 goto err;
517
518 dprintk("%sleft vol %d, right vol %d (0x%04x) to ac97 volume control 0x%04x\n",
519 (val & 0x8000) ? "muted " : "",
520 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
521 val, (int)kcontrol->private_value);
522
523err:
524 mutex_unlock(lock: &dev->lock);
525 return rc;
526}
527
528static int em28xx_vol_get_mute(struct snd_kcontrol *kcontrol,
529 struct snd_ctl_elem_value *value)
530{
531 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
532 struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
533 int nonblock = 0;
534 int val;
535
536 if (dev->disconnected)
537 return -ENODEV;
538
539 if (substream)
540 nonblock = !!(substream->f_flags & O_NONBLOCK);
541 if (nonblock) {
542 if (!mutex_trylock(lock: &dev->lock))
543 return -EAGAIN;
544 } else {
545 mutex_lock(&dev->lock);
546 }
547 val = em28xx_read_ac97(dev, reg: kcontrol->private_value);
548 mutex_unlock(lock: &dev->lock);
549 if (val < 0)
550 return val;
551
552 if (val & 0x8000)
553 value->value.integer.value[0] = 0;
554 else
555 value->value.integer.value[0] = 1;
556
557 dprintk("%sleft vol %d, right vol %d (0x%04x) from ac97 volume control 0x%04x\n",
558 (val & 0x8000) ? "muted " : "",
559 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
560 val, (int)kcontrol->private_value);
561
562 return 0;
563}
564
565static const DECLARE_TLV_DB_SCALE(em28xx_db_scale, -3450, 150, 0);
566
567static int em28xx_cvol_new(struct snd_card *card, struct em28xx *dev,
568 char *name, int id)
569{
570 int err;
571 char ctl_name[44];
572 struct snd_kcontrol *kctl;
573 struct snd_kcontrol_new tmp;
574
575 memset(&tmp, 0, sizeof(tmp));
576 tmp.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
577 tmp.private_value = id;
578 tmp.name = ctl_name;
579
580 /* Add Mute Control */
581 sprintf(buf: ctl_name, fmt: "%s Switch", name);
582 tmp.get = em28xx_vol_get_mute;
583 tmp.put = em28xx_vol_put_mute;
584 tmp.info = snd_ctl_boolean_mono_info;
585 kctl = snd_ctl_new1(kcontrolnew: &tmp, private_data: dev);
586 err = snd_ctl_add(card, kcontrol: kctl);
587 if (err < 0)
588 return err;
589 dprintk("Added control %s for ac97 volume control 0x%04x\n",
590 ctl_name, id);
591
592 memset(&tmp, 0, sizeof(tmp));
593 tmp.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
594 tmp.private_value = id;
595 tmp.name = ctl_name;
596
597 /* Add Volume Control */
598 sprintf(buf: ctl_name, fmt: "%s Volume", name);
599 tmp.get = em28xx_vol_get;
600 tmp.put = em28xx_vol_put;
601 tmp.info = em28xx_vol_info;
602 tmp.tlv.p = em28xx_db_scale;
603 kctl = snd_ctl_new1(kcontrolnew: &tmp, private_data: dev);
604 err = snd_ctl_add(card, kcontrol: kctl);
605 if (err < 0)
606 return err;
607 dprintk("Added control %s for ac97 volume control 0x%04x\n",
608 ctl_name, id);
609
610 return 0;
611}
612
613/*
614 * register/unregister code and data
615 */
616static const struct snd_pcm_ops snd_em28xx_pcm_capture = {
617 .open = snd_em28xx_capture_open,
618 .close = snd_em28xx_pcm_close,
619 .prepare = snd_em28xx_prepare,
620 .trigger = snd_em28xx_capture_trigger,
621 .pointer = snd_em28xx_capture_pointer,
622};
623
624static void em28xx_audio_free_urb(struct em28xx *dev)
625{
626 struct usb_device *udev = interface_to_usbdev(dev->intf);
627 int i;
628
629 for (i = 0; i < dev->adev.num_urb; i++) {
630 struct urb *urb = dev->adev.urb[i];
631
632 if (!urb)
633 continue;
634
635 usb_free_coherent(dev: udev, size: urb->transfer_buffer_length,
636 addr: dev->adev.transfer_buffer[i],
637 dma: urb->transfer_dma);
638
639 usb_free_urb(urb);
640 }
641 kfree(objp: dev->adev.urb);
642 kfree(objp: dev->adev.transfer_buffer);
643 dev->adev.num_urb = 0;
644}
645
646/* high bandwidth multiplier, as encoded in highspeed endpoint descriptors */
647static int em28xx_audio_ep_packet_size(struct usb_device *udev,
648 struct usb_endpoint_descriptor *e)
649{
650 int size = le16_to_cpu(e->wMaxPacketSize);
651
652 if (udev->speed == USB_SPEED_HIGH)
653 return (size & 0x7ff) * (1 + (((size) >> 11) & 0x03));
654
655 return size & 0x7ff;
656}
657
658static int em28xx_audio_urb_init(struct em28xx *dev)
659{
660 struct usb_interface *intf;
661 struct usb_endpoint_descriptor *e, *ep = NULL;
662 struct usb_device *udev = interface_to_usbdev(dev->intf);
663 int i, ep_size, interval, num_urb, npackets;
664 int urb_size, bytes_per_transfer;
665 u8 alt;
666
667 if (dev->ifnum)
668 alt = 1;
669 else
670 alt = 7;
671
672 intf = usb_ifnum_to_if(dev: udev, ifnum: dev->ifnum);
673
674 if (intf->num_altsetting <= alt) {
675 dev_err(&dev->intf->dev, "alt %d doesn't exist on interface %d\n",
676 dev->ifnum, alt);
677 return -ENODEV;
678 }
679
680 for (i = 0; i < intf->altsetting[alt].desc.bNumEndpoints; i++) {
681 e = &intf->altsetting[alt].endpoint[i].desc;
682 if (!usb_endpoint_dir_in(epd: e))
683 continue;
684 if (e->bEndpointAddress == EM28XX_EP_AUDIO) {
685 ep = e;
686 break;
687 }
688 }
689
690 if (!ep) {
691 dev_err(&dev->intf->dev, "Couldn't find an audio endpoint");
692 return -ENODEV;
693 }
694
695 ep_size = em28xx_audio_ep_packet_size(udev, e: ep);
696 interval = 1 << (ep->bInterval - 1);
697
698 dev_info(&dev->intf->dev,
699 "Endpoint 0x%02x %s on intf %d alt %d interval = %d, size %d\n",
700 EM28XX_EP_AUDIO, usb_speed_string(udev->speed),
701 dev->ifnum, alt, interval, ep_size);
702
703 /* Calculate the number and size of URBs to better fit the audio samples */
704
705 /*
706 * Estimate the number of bytes per DMA transfer.
707 *
708 * This is given by the bit rate (for now, only 48000 Hz) multiplied
709 * by 2 channels and 2 bytes/sample divided by the number of microframe
710 * intervals and by the microframe rate (125 us)
711 */
712 bytes_per_transfer = DIV_ROUND_UP(48000 * 2 * 2, 125 * interval);
713
714 /*
715 * Estimate the number of transfer URBs. Don't let it go past the
716 * maximum number of URBs that is known to be supported by the device.
717 */
718 num_urb = DIV_ROUND_UP(bytes_per_transfer, ep_size);
719 if (num_urb > EM28XX_MAX_AUDIO_BUFS)
720 num_urb = EM28XX_MAX_AUDIO_BUFS;
721
722 /*
723 * Now that we know the number of bytes per transfer and the number of
724 * URBs, estimate the typical size of an URB, in order to adjust the
725 * minimal number of packets.
726 */
727 urb_size = bytes_per_transfer / num_urb;
728
729 /*
730 * Now, calculate the amount of audio packets to be filled on each
731 * URB. In order to preserve the old behaviour, use a minimal
732 * threshold for this value.
733 */
734 npackets = EM28XX_MIN_AUDIO_PACKETS;
735 if (urb_size > ep_size * npackets)
736 npackets = DIV_ROUND_UP(urb_size, ep_size);
737
738 dev_info(&dev->intf->dev,
739 "Number of URBs: %d, with %d packets and %d size\n",
740 num_urb, npackets, urb_size);
741
742 /* Estimate the bytes per period */
743 dev->adev.period = urb_size * npackets;
744
745 /* Allocate space to store the number of URBs to be used */
746
747 dev->adev.transfer_buffer = kcalloc(n: num_urb,
748 size: sizeof(*dev->adev.transfer_buffer),
749 GFP_KERNEL);
750 if (!dev->adev.transfer_buffer)
751 return -ENOMEM;
752
753 dev->adev.urb = kcalloc(n: num_urb, size: sizeof(*dev->adev.urb), GFP_KERNEL);
754 if (!dev->adev.urb) {
755 kfree(objp: dev->adev.transfer_buffer);
756 return -ENOMEM;
757 }
758
759 /* Alloc memory for each URB and for each transfer buffer */
760 dev->adev.num_urb = num_urb;
761 for (i = 0; i < num_urb; i++) {
762 struct urb *urb;
763 int j, k;
764 void *buf;
765
766 urb = usb_alloc_urb(iso_packets: npackets, GFP_KERNEL);
767 if (!urb) {
768 em28xx_audio_free_urb(dev);
769 return -ENOMEM;
770 }
771 dev->adev.urb[i] = urb;
772
773 buf = usb_alloc_coherent(dev: udev, size: npackets * ep_size, GFP_KERNEL,
774 dma: &urb->transfer_dma);
775 if (!buf) {
776 dev_err(&dev->intf->dev,
777 "usb_alloc_coherent failed!\n");
778 em28xx_audio_free_urb(dev);
779 return -ENOMEM;
780 }
781 dev->adev.transfer_buffer[i] = buf;
782
783 urb->dev = udev;
784 urb->context = dev;
785 urb->pipe = usb_rcvisocpipe(udev, EM28XX_EP_AUDIO);
786 urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
787 urb->transfer_buffer = buf;
788 urb->interval = interval;
789 urb->complete = em28xx_audio_isocirq;
790 urb->number_of_packets = npackets;
791 urb->transfer_buffer_length = ep_size * npackets;
792
793 for (j = k = 0; j < npackets; j++, k += ep_size) {
794 urb->iso_frame_desc[j].offset = k;
795 urb->iso_frame_desc[j].length = ep_size;
796 }
797 }
798
799 return 0;
800}
801
802static int em28xx_audio_init(struct em28xx *dev)
803{
804 struct em28xx_audio *adev = &dev->adev;
805 struct usb_device *udev = interface_to_usbdev(dev->intf);
806 struct snd_pcm *pcm;
807 struct snd_card *card;
808 static int devnr;
809 int err;
810
811 if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR) {
812 /*
813 * This device does not support the extension (in this case
814 * the device is expecting the snd-usb-audio module or
815 * doesn't have analog audio support at all)
816 */
817 return 0;
818 }
819
820 dev_info(&dev->intf->dev, "Binding audio extension\n");
821
822 kref_get(kref: &dev->ref);
823
824 dev_info(&dev->intf->dev,
825 "em28xx-audio.c: Copyright (C) 2006 Markus Rechberger\n");
826 dev_info(&dev->intf->dev,
827 "em28xx-audio.c: Copyright (C) 2007-2016 Mauro Carvalho Chehab\n");
828
829 err = snd_card_new(parent: &dev->intf->dev, idx: index[devnr], xid: "Em28xx Audio",
830 THIS_MODULE, extra_size: 0, card_ret: &card);
831 if (err < 0)
832 return err;
833
834 spin_lock_init(&adev->slock);
835 adev->sndcard = card;
836 adev->udev = udev;
837
838 err = snd_pcm_new(card, id: "Em28xx Audio", device: 0, playback_count: 0, capture_count: 1, rpcm: &pcm);
839 if (err < 0)
840 goto card_free;
841
842 snd_pcm_set_ops(pcm, direction: SNDRV_PCM_STREAM_CAPTURE, ops: &snd_em28xx_pcm_capture);
843 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, size: 0, max: 0);
844 pcm->info_flags = 0;
845 pcm->private_data = dev;
846 strscpy(pcm->name, "Empia 28xx Capture", sizeof(pcm->name));
847
848 strscpy(card->driver, "Em28xx-Audio", sizeof(card->driver));
849 strscpy(card->shortname, "Em28xx Audio", sizeof(card->shortname));
850 strscpy(card->longname, "Empia Em28xx Audio", sizeof(card->longname));
851
852 INIT_WORK(&adev->wq_trigger, audio_trigger);
853
854 if (dev->audio_mode.ac97 != EM28XX_NO_AC97) {
855 em28xx_cvol_new(card, dev, name: "Video", AC97_VIDEO);
856 em28xx_cvol_new(card, dev, name: "Line In", AC97_LINE);
857 em28xx_cvol_new(card, dev, name: "Phone", AC97_PHONE);
858 em28xx_cvol_new(card, dev, name: "Microphone", AC97_MIC);
859 em28xx_cvol_new(card, dev, name: "CD", AC97_CD);
860 em28xx_cvol_new(card, dev, name: "AUX", AC97_AUX);
861 em28xx_cvol_new(card, dev, name: "PCM", AC97_PCM);
862
863 em28xx_cvol_new(card, dev, name: "Master", AC97_MASTER);
864 em28xx_cvol_new(card, dev, name: "Line", AC97_HEADPHONE);
865 em28xx_cvol_new(card, dev, name: "Mono", AC97_MASTER_MONO);
866 em28xx_cvol_new(card, dev, name: "LFE", AC97_CENTER_LFE_MASTER);
867 em28xx_cvol_new(card, dev, name: "Surround", AC97_SURROUND_MASTER);
868 }
869
870 err = em28xx_audio_urb_init(dev);
871 if (err)
872 goto card_free;
873
874 err = snd_card_register(card);
875 if (err < 0)
876 goto urb_free;
877
878 dev_info(&dev->intf->dev, "Audio extension successfully initialized\n");
879 return 0;
880
881urb_free:
882 em28xx_audio_free_urb(dev);
883
884card_free:
885 snd_card_free(card);
886 adev->sndcard = NULL;
887
888 return err;
889}
890
891static int em28xx_audio_fini(struct em28xx *dev)
892{
893 if (!dev)
894 return 0;
895
896 if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR) {
897 /*
898 * This device does not support the extension (in this case
899 * the device is expecting the snd-usb-audio module or
900 * doesn't have analog audio support at all)
901 */
902 return 0;
903 }
904
905 dev_info(&dev->intf->dev, "Closing audio extension\n");
906
907 if (dev->adev.sndcard) {
908 snd_card_disconnect(card: dev->adev.sndcard);
909 flush_work(work: &dev->adev.wq_trigger);
910
911 em28xx_audio_free_urb(dev);
912
913 snd_card_free(card: dev->adev.sndcard);
914 dev->adev.sndcard = NULL;
915 }
916
917 kref_put(kref: &dev->ref, release: em28xx_free_device);
918 return 0;
919}
920
921static int em28xx_audio_suspend(struct em28xx *dev)
922{
923 if (!dev)
924 return 0;
925
926 if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR)
927 return 0;
928
929 dev_info(&dev->intf->dev, "Suspending audio extension\n");
930 em28xx_deinit_isoc_audio(dev);
931 atomic_set(v: &dev->adev.stream_started, i: 0);
932 return 0;
933}
934
935static int em28xx_audio_resume(struct em28xx *dev)
936{
937 if (!dev)
938 return 0;
939
940 if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR)
941 return 0;
942
943 dev_info(&dev->intf->dev, "Resuming audio extension\n");
944 /* Nothing to do other than schedule_work() ?? */
945 schedule_work(work: &dev->adev.wq_trigger);
946 return 0;
947}
948
949static struct em28xx_ops audio_ops = {
950 .id = EM28XX_AUDIO,
951 .name = "Em28xx Audio Extension",
952 .init = em28xx_audio_init,
953 .fini = em28xx_audio_fini,
954 .suspend = em28xx_audio_suspend,
955 .resume = em28xx_audio_resume,
956};
957
958static int __init em28xx_alsa_register(void)
959{
960 return em28xx_register_extension(dev: &audio_ops);
961}
962
963static void __exit em28xx_alsa_unregister(void)
964{
965 em28xx_unregister_extension(dev: &audio_ops);
966}
967
968MODULE_LICENSE("GPL v2");
969MODULE_AUTHOR("Markus Rechberger <mrechberger@gmail.com>");
970MODULE_AUTHOR("Mauro Carvalho Chehab");
971MODULE_DESCRIPTION(DRIVER_DESC " - audio interface");
972MODULE_VERSION(EM28XX_VERSION);
973
974module_init(em28xx_alsa_register);
975module_exit(em28xx_alsa_unregister);
976

source code of linux/drivers/media/usb/em28xx/em28xx-audio.c