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28#include <linux/kernel.h>
29#include <linux/usb.h>
30#include <linux/init.h>
31#include <linux/sound.h>
32#include <linux/spinlock.h>
33#include <linux/soundcard.h>
34#include <linux/slab.h>
35#include <linux/vmalloc.h>
36#include <linux/proc_fs.h>
37#include <linux/module.h>
38#include <sound/core.h>
39#include <sound/pcm.h>
40#include <sound/pcm_params.h>
41#include <sound/info.h>
42#include <sound/initval.h>
43#include <sound/control.h>
44#include <sound/tlv.h>
45#include <media/v4l2-common.h>
46#include "em28xx.h"
47
48static int debug;
49module_param(debug, int, 0644);
50MODULE_PARM_DESC(debug, "activates debug info");
51
52#define dprintk(fmt, arg...) do { \
53 if (debug) \
54 printk(KERN_INFO "em28xx-audio %s: " fmt, \
55 __func__, ##arg); \
56 } while (0)
57
58static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
59
60static int em28xx_deinit_isoc_audio(struct em28xx *dev)
61{
62 int i;
63
64 dprintk("Stopping isoc\n");
65 for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
66 if (!irqs_disabled())
67 usb_kill_urb(dev->adev.urb[i]);
68 else
69 usb_unlink_urb(dev->adev.urb[i]);
70
71 usb_free_urb(dev->adev.urb[i]);
72 dev->adev.urb[i] = NULL;
73
74 kfree(dev->adev.transfer_buffer[i]);
75 dev->adev.transfer_buffer[i] = NULL;
76 }
77
78 return 0;
79}
80
81static void em28xx_audio_isocirq(struct urb *urb)
82{
83 struct em28xx *dev = urb->context;
84 int i;
85 unsigned int oldptr;
86 int period_elapsed = 0;
87 int status;
88 unsigned char *cp;
89 unsigned int stride;
90 struct snd_pcm_substream *substream;
91 struct snd_pcm_runtime *runtime;
92
93 switch (urb->status) {
94 case 0:
95 case -ETIMEDOUT:
96 break;
97 case -ECONNRESET:
98 case -ENOENT:
99 case -ESHUTDOWN:
100 return;
101 default:
102 dprintk("urb completition error %d.\n", urb->status);
103 break;
104 }
105
106 if (atomic_read(&dev->stream_started) == 0)
107 return;
108
109 if (dev->adev.capture_pcm_substream) {
110 substream = dev->adev.capture_pcm_substream;
111 runtime = substream->runtime;
112 stride = runtime->frame_bits >> 3;
113
114 for (i = 0; i < urb->number_of_packets; i++) {
115 int length =
116 urb->iso_frame_desc[i].actual_length / stride;
117 cp = (unsigned char *)urb->transfer_buffer +
118 urb->iso_frame_desc[i].offset;
119
120 if (!length)
121 continue;
122
123 oldptr = dev->adev.hwptr_done_capture;
124 if (oldptr + length >= runtime->buffer_size) {
125 unsigned int cnt =
126 runtime->buffer_size - oldptr;
127 memcpy(runtime->dma_area + oldptr * stride, cp,
128 cnt * stride);
129 memcpy(runtime->dma_area, cp + cnt * stride,
130 length * stride - cnt * stride);
131 } else {
132 memcpy(runtime->dma_area + oldptr * stride, cp,
133 length * stride);
134 }
135
136 snd_pcm_stream_lock(substream);
137
138 dev->adev.hwptr_done_capture += length;
139 if (dev->adev.hwptr_done_capture >=
140 runtime->buffer_size)
141 dev->adev.hwptr_done_capture -=
142 runtime->buffer_size;
143
144 dev->adev.capture_transfer_done += length;
145 if (dev->adev.capture_transfer_done >=
146 runtime->period_size) {
147 dev->adev.capture_transfer_done -=
148 runtime->period_size;
149 period_elapsed = 1;
150 }
151
152 snd_pcm_stream_unlock(substream);
153 }
154 if (period_elapsed)
155 snd_pcm_period_elapsed(substream);
156 }
157 urb->status = 0;
158
159 status = usb_submit_urb(urb, GFP_ATOMIC);
160 if (status < 0) {
161 em28xx_errdev("resubmit of audio urb failed (error=%i)\n",
162 status);
163 }
164 return;
165}
166
167static int em28xx_init_audio_isoc(struct em28xx *dev)
168{
169 int i, errCode;
170 const int sb_size = EM28XX_NUM_AUDIO_PACKETS *
171 EM28XX_AUDIO_MAX_PACKET_SIZE;
172
173 dprintk("Starting isoc transfers\n");
174
175 for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
176 struct urb *urb;
177 int j, k;
178
179 dev->adev.transfer_buffer[i] = kmalloc(sb_size, GFP_ATOMIC);
180 if (!dev->adev.transfer_buffer[i])
181 return -ENOMEM;
182
183 memset(dev->adev.transfer_buffer[i], 0x80, sb_size);
184 urb = usb_alloc_urb(EM28XX_NUM_AUDIO_PACKETS, GFP_ATOMIC);
185 if (!urb) {
186 em28xx_errdev("usb_alloc_urb failed!\n");
187 for (j = 0; j < i; j++) {
188 usb_free_urb(dev->adev.urb[j]);
189 kfree(dev->adev.transfer_buffer[j]);
190 }
191 return -ENOMEM;
192 }
193
194 urb->dev = dev->udev;
195 urb->context = dev;
196 urb->pipe = usb_rcvisocpipe(dev->udev, 0x83);
197 urb->transfer_flags = URB_ISO_ASAP;
198 urb->transfer_buffer = dev->adev.transfer_buffer[i];
199 urb->interval = 1;
200 urb->complete = em28xx_audio_isocirq;
201 urb->number_of_packets = EM28XX_NUM_AUDIO_PACKETS;
202 urb->transfer_buffer_length = sb_size;
203
204 for (j = k = 0; j < EM28XX_NUM_AUDIO_PACKETS;
205 j++, k += EM28XX_AUDIO_MAX_PACKET_SIZE) {
206 urb->iso_frame_desc[j].offset = k;
207 urb->iso_frame_desc[j].length =
208 EM28XX_AUDIO_MAX_PACKET_SIZE;
209 }
210 dev->adev.urb[i] = urb;
211 }
212
213 for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
214 errCode = usb_submit_urb(dev->adev.urb[i], GFP_ATOMIC);
215 if (errCode) {
216 em28xx_errdev("submit of audio urb failed\n");
217 em28xx_deinit_isoc_audio(dev);
218 atomic_set(&dev->stream_started, 0);
219 return errCode;
220 }
221
222 }
223
224 return 0;
225}
226
227static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
228 size_t size)
229{
230 struct snd_pcm_runtime *runtime = subs->runtime;
231
232 dprintk("Allocating vbuffer\n");
233 if (runtime->dma_area) {
234 if (runtime->dma_bytes > size)
235 return 0;
236
237 vfree(runtime->dma_area);
238 }
239 runtime->dma_area = vmalloc(size);
240 if (!runtime->dma_area)
241 return -ENOMEM;
242
243 runtime->dma_bytes = size;
244
245 return 0;
246}
247
248static struct snd_pcm_hardware snd_em28xx_hw_capture = {
249 .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
250 SNDRV_PCM_INFO_MMAP |
251 SNDRV_PCM_INFO_INTERLEAVED |
252 SNDRV_PCM_INFO_BATCH |
253 SNDRV_PCM_INFO_MMAP_VALID,
254
255 .formats = SNDRV_PCM_FMTBIT_S16_LE,
256
257 .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_KNOT,
258
259 .rate_min = 48000,
260 .rate_max = 48000,
261 .channels_min = 2,
262 .channels_max = 2,
263 .buffer_bytes_max = 62720 * 8,
264 .period_bytes_min = 64,
265 .period_bytes_max = 12544,
266 .periods_min = 2,
267 .periods_max = 98,
268};
269
270static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
271{
272 struct em28xx *dev = snd_pcm_substream_chip(substream);
273 struct snd_pcm_runtime *runtime = substream->runtime;
274 int ret = 0;
275
276 dprintk("opening device and trying to acquire exclusive lock\n");
277
278 if (!dev) {
279 em28xx_err("BUG: em28xx can't find device struct."
280 " Can't proceed with open\n");
281 return -ENODEV;
282 }
283
284 runtime->hw = snd_em28xx_hw_capture;
285 if ((dev->alt == 0 || dev->audio_ifnum) && dev->adev.users == 0) {
286 if (dev->audio_ifnum)
287 dev->alt = 1;
288 else
289 dev->alt = 7;
290
291 dprintk("changing alternate number on interface %d to %d\n",
292 dev->audio_ifnum, dev->alt);
293 usb_set_interface(dev->udev, dev->audio_ifnum, dev->alt);
294
295
296 dev->mute = 0;
297 mutex_lock(&dev->lock);
298 ret = em28xx_audio_analog_set(dev);
299 if (ret < 0)
300 goto err;
301
302 dev->adev.users++;
303 mutex_unlock(&dev->lock);
304 }
305
306 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
307 dev->adev.capture_pcm_substream = substream;
308 runtime->private_data = dev;
309
310 return 0;
311err:
312 mutex_unlock(&dev->lock);
313
314 em28xx_err("Error while configuring em28xx mixer\n");
315 return ret;
316}
317
318static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
319{
320 struct em28xx *dev = snd_pcm_substream_chip(substream);
321
322 dprintk("closing device\n");
323
324 dev->mute = 1;
325 mutex_lock(&dev->lock);
326 dev->adev.users--;
327 if (atomic_read(&dev->stream_started) > 0) {
328 atomic_set(&dev->stream_started, 0);
329 schedule_work(&dev->wq_trigger);
330 }
331
332 em28xx_audio_analog_set(dev);
333 if (substream->runtime->dma_area) {
334 dprintk("freeing\n");
335 vfree(substream->runtime->dma_area);
336 substream->runtime->dma_area = NULL;
337 }
338 mutex_unlock(&dev->lock);
339
340 return 0;
341}
342
343static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
344 struct snd_pcm_hw_params *hw_params)
345{
346 unsigned int channels, rate, format;
347 int ret;
348
349 dprintk("Setting capture parameters\n");
350
351 ret = snd_pcm_alloc_vmalloc_buffer(substream,
352 params_buffer_bytes(hw_params));
353 if (ret < 0)
354 return ret;
355 format = params_format(hw_params);
356 rate = params_rate(hw_params);
357 channels = params_channels(hw_params);
358
359
360
361
362 return 0;
363}
364
365static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
366{
367 struct em28xx *dev = snd_pcm_substream_chip(substream);
368
369 dprintk("Stop capture, if needed\n");
370
371 if (atomic_read(&dev->stream_started) > 0) {
372 atomic_set(&dev->stream_started, 0);
373 schedule_work(&dev->wq_trigger);
374 }
375
376 return 0;
377}
378
379static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
380{
381 struct em28xx *dev = snd_pcm_substream_chip(substream);
382
383 dev->adev.hwptr_done_capture = 0;
384 dev->adev.capture_transfer_done = 0;
385
386 return 0;
387}
388
389static void audio_trigger(struct work_struct *work)
390{
391 struct em28xx *dev = container_of(work, struct em28xx, wq_trigger);
392
393 if (atomic_read(&dev->stream_started)) {
394 dprintk("starting capture");
395 em28xx_init_audio_isoc(dev);
396 } else {
397 dprintk("stopping capture");
398 em28xx_deinit_isoc_audio(dev);
399 }
400}
401
402static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
403 int cmd)
404{
405 struct em28xx *dev = snd_pcm_substream_chip(substream);
406 int retval = 0;
407
408 switch (cmd) {
409 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
410 case SNDRV_PCM_TRIGGER_RESUME:
411 case SNDRV_PCM_TRIGGER_START:
412 atomic_set(&dev->stream_started, 1);
413 break;
414 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
415 case SNDRV_PCM_TRIGGER_SUSPEND:
416 case SNDRV_PCM_TRIGGER_STOP:
417 atomic_set(&dev->stream_started, 0);
418 break;
419 default:
420 retval = -EINVAL;
421 }
422 schedule_work(&dev->wq_trigger);
423 return retval;
424}
425
426static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
427 *substream)
428{
429 unsigned long flags;
430 struct em28xx *dev;
431 snd_pcm_uframes_t hwptr_done;
432
433 dev = snd_pcm_substream_chip(substream);
434 spin_lock_irqsave(&dev->adev.slock, flags);
435 hwptr_done = dev->adev.hwptr_done_capture;
436 spin_unlock_irqrestore(&dev->adev.slock, flags);
437
438 return hwptr_done;
439}
440
441static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
442 unsigned long offset)
443{
444 void *pageptr = subs->runtime->dma_area + offset;
445
446 return vmalloc_to_page(pageptr);
447}
448
449
450
451
452static int em28xx_vol_info(struct snd_kcontrol *kcontrol,
453 struct snd_ctl_elem_info *info)
454{
455 info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
456 info->count = 2;
457 info->value.integer.min = 0;
458 info->value.integer.max = 0x1f;
459
460 return 0;
461}
462
463static int em28xx_vol_put(struct snd_kcontrol *kcontrol,
464 struct snd_ctl_elem_value *value)
465{
466 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
467 u16 val = (0x1f - (value->value.integer.value[0] & 0x1f)) |
468 (0x1f - (value->value.integer.value[1] & 0x1f)) << 8;
469 int rc;
470
471 mutex_lock(&dev->lock);
472 rc = em28xx_read_ac97(dev, kcontrol->private_value);
473 if (rc < 0)
474 goto err;
475
476 val |= rc & 0x8000;
477
478 rc = em28xx_write_ac97(dev, kcontrol->private_value, val);
479 if (rc < 0)
480 goto err;
481
482 dprintk("%sleft vol %d, right vol %d (0x%04x) to ac97 volume control 0x%04x\n",
483 (val & 0x8000) ? "muted " : "",
484 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
485 val, (int)kcontrol->private_value);
486
487err:
488 mutex_unlock(&dev->lock);
489 return rc;
490}
491
492static int em28xx_vol_get(struct snd_kcontrol *kcontrol,
493 struct snd_ctl_elem_value *value)
494{
495 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
496 int val;
497
498 mutex_lock(&dev->lock);
499 val = em28xx_read_ac97(dev, kcontrol->private_value);
500 mutex_unlock(&dev->lock);
501 if (val < 0)
502 return val;
503
504 dprintk("%sleft vol %d, right vol %d (0x%04x) from ac97 volume control 0x%04x\n",
505 (val & 0x8000) ? "muted " : "",
506 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
507 val, (int)kcontrol->private_value);
508
509 value->value.integer.value[0] = 0x1f - (val & 0x1f);
510 value->value.integer.value[1] = 0x1f - ((val << 8) & 0x1f);
511
512 return 0;
513}
514
515static int em28xx_vol_put_mute(struct snd_kcontrol *kcontrol,
516 struct snd_ctl_elem_value *value)
517{
518 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
519 u16 val = value->value.integer.value[0];
520 int rc;
521
522 mutex_lock(&dev->lock);
523 rc = em28xx_read_ac97(dev, kcontrol->private_value);
524 if (rc < 0)
525 goto err;
526
527 if (val)
528 rc &= 0x1f1f;
529 else
530 rc |= 0x8000;
531
532 rc = em28xx_write_ac97(dev, kcontrol->private_value, rc);
533 if (rc < 0)
534 goto err;
535
536 dprintk("%sleft vol %d, right vol %d (0x%04x) to ac97 volume control 0x%04x\n",
537 (val & 0x8000) ? "muted " : "",
538 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
539 val, (int)kcontrol->private_value);
540
541err:
542 mutex_unlock(&dev->lock);
543 return rc;
544}
545
546static int em28xx_vol_get_mute(struct snd_kcontrol *kcontrol,
547 struct snd_ctl_elem_value *value)
548{
549 struct em28xx *dev = snd_kcontrol_chip(kcontrol);
550 int val;
551
552 mutex_lock(&dev->lock);
553 val = em28xx_read_ac97(dev, kcontrol->private_value);
554 mutex_unlock(&dev->lock);
555 if (val < 0)
556 return val;
557
558 if (val & 0x8000)
559 value->value.integer.value[0] = 0;
560 else
561 value->value.integer.value[0] = 1;
562
563 dprintk("%sleft vol %d, right vol %d (0x%04x) from ac97 volume control 0x%04x\n",
564 (val & 0x8000) ? "muted " : "",
565 0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
566 val, (int)kcontrol->private_value);
567
568 return 0;
569}
570
571static const DECLARE_TLV_DB_SCALE(em28xx_db_scale, -3450, 150, 0);
572
573static int em28xx_cvol_new(struct snd_card *card, struct em28xx *dev,
574 char *name, int id)
575{
576 int err;
577 char ctl_name[44];
578 struct snd_kcontrol *kctl;
579 struct snd_kcontrol_new tmp;
580
581 memset (&tmp, 0, sizeof(tmp));
582 tmp.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
583 tmp.private_value = id,
584 tmp.name = ctl_name,
585
586
587 sprintf(ctl_name, "%s Switch", name);
588 tmp.get = em28xx_vol_get_mute;
589 tmp.put = em28xx_vol_put_mute;
590 tmp.info = snd_ctl_boolean_mono_info;
591 kctl = snd_ctl_new1(&tmp, dev);
592 err = snd_ctl_add(card, kctl);
593 if (err < 0)
594 return err;
595 dprintk("Added control %s for ac97 volume control 0x%04x\n",
596 ctl_name, id);
597
598 memset (&tmp, 0, sizeof(tmp));
599 tmp.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
600 tmp.private_value = id,
601 tmp.name = ctl_name,
602
603
604 sprintf(ctl_name, "%s Volume", name);
605 tmp.get = em28xx_vol_get;
606 tmp.put = em28xx_vol_put;
607 tmp.info = em28xx_vol_info;
608 tmp.tlv.p = em28xx_db_scale,
609 kctl = snd_ctl_new1(&tmp, dev);
610 err = snd_ctl_add(card, kctl);
611 if (err < 0)
612 return err;
613 dprintk("Added control %s for ac97 volume control 0x%04x\n",
614 ctl_name, id);
615
616 return 0;
617}
618
619
620
621
622static struct snd_pcm_ops snd_em28xx_pcm_capture = {
623 .open = snd_em28xx_capture_open,
624 .close = snd_em28xx_pcm_close,
625 .ioctl = snd_pcm_lib_ioctl,
626 .hw_params = snd_em28xx_hw_capture_params,
627 .hw_free = snd_em28xx_hw_capture_free,
628 .prepare = snd_em28xx_prepare,
629 .trigger = snd_em28xx_capture_trigger,
630 .pointer = snd_em28xx_capture_pointer,
631 .page = snd_pcm_get_vmalloc_page,
632};
633
634static int em28xx_audio_init(struct em28xx *dev)
635{
636 struct em28xx_audio *adev = &dev->adev;
637 struct snd_pcm *pcm;
638 struct snd_card *card;
639 static int devnr;
640 int err;
641
642 if (!dev->has_alsa_audio || dev->audio_ifnum < 0) {
643
644
645
646 return 0;
647 }
648
649 printk(KERN_INFO "em28xx-audio.c: probing for em28xx Audio Vendor Class\n");
650 printk(KERN_INFO "em28xx-audio.c: Copyright (C) 2006 Markus "
651 "Rechberger\n");
652 printk(KERN_INFO "em28xx-audio.c: Copyright (C) 2007-2011 Mauro Carvalho Chehab\n");
653
654 err = snd_card_create(index[devnr], "Em28xx Audio", THIS_MODULE, 0,
655 &card);
656 if (err < 0)
657 return err;
658
659 spin_lock_init(&adev->slock);
660 err = snd_pcm_new(card, "Em28xx Audio", 0, 0, 1, &pcm);
661 if (err < 0) {
662 snd_card_free(card);
663 return err;
664 }
665
666 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_em28xx_pcm_capture);
667 pcm->info_flags = 0;
668 pcm->private_data = dev;
669 strcpy(pcm->name, "Empia 28xx Capture");
670
671 snd_card_set_dev(card, &dev->udev->dev);
672 strcpy(card->driver, "Em28xx-Audio");
673 strcpy(card->shortname, "Em28xx Audio");
674 strcpy(card->longname, "Empia Em28xx Audio");
675
676 INIT_WORK(&dev->wq_trigger, audio_trigger);
677
678 if (dev->audio_mode.ac97 != EM28XX_NO_AC97) {
679 em28xx_cvol_new(card, dev, "Video", AC97_VIDEO_VOL);
680 em28xx_cvol_new(card, dev, "Line In", AC97_LINEIN_VOL);
681 em28xx_cvol_new(card, dev, "Phone", AC97_PHONE_VOL);
682 em28xx_cvol_new(card, dev, "Microphone", AC97_PHONE_VOL);
683 em28xx_cvol_new(card, dev, "CD", AC97_CD_VOL);
684 em28xx_cvol_new(card, dev, "AUX", AC97_AUX_VOL);
685 em28xx_cvol_new(card, dev, "PCM", AC97_PCM_OUT_VOL);
686
687 em28xx_cvol_new(card, dev, "Master", AC97_MASTER_VOL);
688 em28xx_cvol_new(card, dev, "Line", AC97_LINE_LEVEL_VOL);
689 em28xx_cvol_new(card, dev, "Mono", AC97_MASTER_MONO_VOL);
690 em28xx_cvol_new(card, dev, "LFE", AC97_LFE_MASTER_VOL);
691 em28xx_cvol_new(card, dev, "Surround", AC97_SURR_MASTER_VOL);
692 }
693
694 err = snd_card_register(card);
695 if (err < 0) {
696 snd_card_free(card);
697 return err;
698 }
699 adev->sndcard = card;
700 adev->udev = dev->udev;
701
702 return 0;
703}
704
705static int em28xx_audio_fini(struct em28xx *dev)
706{
707 if (dev == NULL)
708 return 0;
709
710 if (dev->has_alsa_audio != 1) {
711
712
713
714 return 0;
715 }
716
717 if (dev->adev.sndcard) {
718 snd_card_free(dev->adev.sndcard);
719 dev->adev.sndcard = NULL;
720 }
721
722 return 0;
723}
724
725static struct em28xx_ops audio_ops = {
726 .id = EM28XX_AUDIO,
727 .name = "Em28xx Audio Extension",
728 .init = em28xx_audio_init,
729 .fini = em28xx_audio_fini,
730};
731
732static int __init em28xx_alsa_register(void)
733{
734 return em28xx_register_extension(&audio_ops);
735}
736
737static void __exit em28xx_alsa_unregister(void)
738{
739 em28xx_unregister_extension(&audio_ops);
740}
741
742MODULE_LICENSE("GPL");
743MODULE_AUTHOR("Markus Rechberger <mrechberger@gmail.com>");
744MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
745MODULE_DESCRIPTION("Em28xx Audio driver");
746
747module_init(em28xx_alsa_register);
748module_exit(em28xx_alsa_unregister);
749
