1 /*
2  *  Empiatech em28x1 audio extension
3  *
4  *  Copyright (C) 2006 Markus Rechberger <mrechberger@gmail.com>
5  *
6  *  Copyright (C) 2007-2016 Mauro Carvalho Chehab
7  *	- Port to work with the in-kernel driver
8  *	- Cleanups, fixes, alsa-controls, etc.
9  *
10  *  This driver is based on my previous au600 usb pstn audio driver
11  *  and inherits all the copyrights
12  *
13  *  This program is free software; you can redistribute it and/or modify
14  *  it under the terms of the GNU General Public License as published by
15  *  the Free Software Foundation; either version 2 of the License, or
16  *  (at your option) any later version.
17  *
18  *  This program is distributed in the hope that it will be useful,
19  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  *  GNU General Public License for more details.
22  *
23  *  You should have received a copy of the GNU General Public License
24  *  along with this program; if not, write to the Free Software
25  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26  */
27 
28 #include "em28xx.h"
29 
30 #include <linux/kernel.h>
31 #include <linux/usb.h>
32 #include <linux/init.h>
33 #include <linux/sound.h>
34 #include <linux/spinlock.h>
35 #include <linux/soundcard.h>
36 #include <linux/slab.h>
37 #include <linux/vmalloc.h>
38 #include <linux/proc_fs.h>
39 #include <linux/module.h>
40 #include <sound/core.h>
41 #include <sound/pcm.h>
42 #include <sound/pcm_params.h>
43 #include <sound/info.h>
44 #include <sound/initval.h>
45 #include <sound/control.h>
46 #include <sound/tlv.h>
47 #include <sound/ac97_codec.h>
48 #include <media/v4l2-common.h>
49 
50 static int debug;
51 module_param(debug, int, 0644);
52 MODULE_PARM_DESC(debug, "activates debug info");
53 
54 #define EM28XX_MAX_AUDIO_BUFS		5
55 #define EM28XX_MIN_AUDIO_PACKETS	64
56 
57 #define dprintk(fmt, arg...) do {					\
58 	if (debug)						\
59 		dev_printk(KERN_DEBUG, &dev->intf->dev,			\
60 			   "video: %s: " fmt, __func__, ## arg);	\
61 } while (0)
62 
63 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
64 
65 static int em28xx_deinit_isoc_audio(struct em28xx *dev)
66 {
67 	int i;
68 
69 	dprintk("Stopping isoc\n");
70 	for (i = 0; i < dev->adev.num_urb; i++) {
71 		struct urb *urb = dev->adev.urb[i];
72 
73 		if (!irqs_disabled())
74 			usb_kill_urb(urb);
75 		else
76 			usb_unlink_urb(urb);
77 	}
78 
79 	return 0;
80 }
81 
82 static void em28xx_audio_isocirq(struct urb *urb)
83 {
84 	struct em28xx            *dev = urb->context;
85 	int                      i;
86 	unsigned int             oldptr;
87 	int                      period_elapsed = 0;
88 	int                      status;
89 	unsigned char            *cp;
90 	unsigned int             stride;
91 	struct snd_pcm_substream *substream;
92 	struct snd_pcm_runtime   *runtime;
93 
94 	if (dev->disconnected) {
95 		dprintk("device disconnected while streaming. URB status=%d.\n",
96 			urb->status);
97 		atomic_set(&dev->adev.stream_started, 0);
98 		return;
99 	}
100 
101 	switch (urb->status) {
102 	case 0:             /* success */
103 	case -ETIMEDOUT:    /* NAK */
104 		break;
105 	case -ECONNRESET:   /* kill */
106 	case -ENOENT:
107 	case -ESHUTDOWN:
108 		return;
109 	default:            /* error */
110 		dprintk("urb completition error %d.\n", urb->status);
111 		break;
112 	}
113 
114 	if (atomic_read(&dev->adev.stream_started) == 0)
115 		return;
116 
117 	if (dev->adev.capture_pcm_substream) {
118 		substream = dev->adev.capture_pcm_substream;
119 		runtime = substream->runtime;
120 		stride = runtime->frame_bits >> 3;
121 
122 		for (i = 0; i < urb->number_of_packets; i++) {
123 			int length =
124 			    urb->iso_frame_desc[i].actual_length / stride;
125 			cp = (unsigned char *)urb->transfer_buffer +
126 			    urb->iso_frame_desc[i].offset;
127 
128 			if (!length)
129 				continue;
130 
131 			oldptr = dev->adev.hwptr_done_capture;
132 			if (oldptr + length >= runtime->buffer_size) {
133 				unsigned int cnt =
134 				    runtime->buffer_size - oldptr;
135 				memcpy(runtime->dma_area + oldptr * stride, cp,
136 				       cnt * stride);
137 				memcpy(runtime->dma_area, cp + cnt * stride,
138 				       length * stride - cnt * stride);
139 			} else {
140 				memcpy(runtime->dma_area + oldptr * stride, cp,
141 				       length * stride);
142 			}
143 
144 			snd_pcm_stream_lock(substream);
145 
146 			dev->adev.hwptr_done_capture += length;
147 			if (dev->adev.hwptr_done_capture >=
148 			    runtime->buffer_size)
149 				dev->adev.hwptr_done_capture -=
150 				    runtime->buffer_size;
151 
152 			dev->adev.capture_transfer_done += length;
153 			if (dev->adev.capture_transfer_done >=
154 			    runtime->period_size) {
155 				dev->adev.capture_transfer_done -=
156 				    runtime->period_size;
157 				period_elapsed = 1;
158 			}
159 
160 			snd_pcm_stream_unlock(substream);
161 		}
162 		if (period_elapsed)
163 			snd_pcm_period_elapsed(substream);
164 	}
165 	urb->status = 0;
166 
167 	status = usb_submit_urb(urb, GFP_ATOMIC);
168 	if (status < 0)
169 		dev_err(&dev->intf->dev,
170 			"resubmit of audio urb failed (error=%i)\n",
171 			status);
172 	return;
173 }
174 
175 static int em28xx_init_audio_isoc(struct em28xx *dev)
176 {
177 	int       i, errCode;
178 
179 	dprintk("Starting isoc transfers\n");
180 
181 	/* Start streaming */
182 	for (i = 0; i < dev->adev.num_urb; i++) {
183 		memset(dev->adev.transfer_buffer[i], 0x80,
184 		       dev->adev.urb[i]->transfer_buffer_length);
185 
186 		errCode = usb_submit_urb(dev->adev.urb[i], GFP_ATOMIC);
187 		if (errCode) {
188 			dev_err(&dev->intf->dev,
189 				"submit of audio urb failed (error=%i)\n",
190 				errCode);
191 			em28xx_deinit_isoc_audio(dev);
192 			atomic_set(&dev->adev.stream_started, 0);
193 			return errCode;
194 		}
195 
196 	}
197 
198 	return 0;
199 }
200 
201 static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
202 					size_t size)
203 {
204 	struct em28xx *dev = snd_pcm_substream_chip(subs);
205 	struct snd_pcm_runtime *runtime = subs->runtime;
206 
207 	dprintk("Allocating vbuffer\n");
208 	if (runtime->dma_area) {
209 		if (runtime->dma_bytes > size)
210 			return 0;
211 
212 		vfree(runtime->dma_area);
213 	}
214 	runtime->dma_area = vmalloc(size);
215 	if (!runtime->dma_area)
216 		return -ENOMEM;
217 
218 	runtime->dma_bytes = size;
219 
220 	return 0;
221 }
222 
223 static struct snd_pcm_hardware snd_em28xx_hw_capture = {
224 	.info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
225 		SNDRV_PCM_INFO_MMAP           |
226 		SNDRV_PCM_INFO_INTERLEAVED    |
227 		SNDRV_PCM_INFO_BATCH	      |
228 		SNDRV_PCM_INFO_MMAP_VALID,
229 
230 	.formats = SNDRV_PCM_FMTBIT_S16_LE,
231 
232 	.rates = SNDRV_PCM_RATE_48000,
233 
234 	.rate_min = 48000,
235 	.rate_max = 48000,
236 	.channels_min = 2,
237 	.channels_max = 2,
238 	.buffer_bytes_max = 62720 * 8,	/* just about the value in usbaudio.c */
239 
240 	/*
241 	 * The period is 12.288 bytes. Allow a 10% of variation along its
242 	 * value, in order to avoid overruns/underruns due to some clock
243 	 * drift.
244 	 *
245 	 * FIXME: This period assumes 64 packets, and a 48000 PCM rate.
246 	 * Calculate it dynamically.
247 	 */
248 	.period_bytes_min = 11059,
249 	.period_bytes_max = 13516,
250 
251 	.periods_min = 2,
252 	.periods_max = 98,		/* 12544, */
253 };
254 
255 static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
256 {
257 	struct em28xx *dev = snd_pcm_substream_chip(substream);
258 	struct snd_pcm_runtime *runtime = substream->runtime;
259 	int nonblock, ret = 0;
260 
261 	if (!dev) {
262 		pr_err("em28xx-audio: BUG: em28xx can't find device struct. Can't proceed with open\n");
263 		return -ENODEV;
264 	}
265 
266 	if (dev->disconnected)
267 		return -ENODEV;
268 
269 	dprintk("opening device and trying to acquire exclusive lock\n");
270 
271 	nonblock = !!(substream->f_flags & O_NONBLOCK);
272 	if (nonblock) {
273 		if (!mutex_trylock(&dev->lock))
274 			return -EAGAIN;
275 	} else
276 		mutex_lock(&dev->lock);
277 
278 	runtime->hw = snd_em28xx_hw_capture;
279 
280 	if (dev->adev.users == 0) {
281 		if (dev->alt == 0 || dev->is_audio_only) {
282 			struct usb_device *udev = interface_to_usbdev(dev->intf);
283 
284 			if (dev->is_audio_only)
285 				/* audio is on a separate interface */
286 				dev->alt = 1;
287 			else
288 				/* audio is on the same interface as video */
289 				dev->alt = 7;
290 				/*
291 				 * FIXME: The intention seems to be to select
292 				 * the alt setting with the largest
293 				 * wMaxPacketSize for the video endpoint.
294 				 * At least dev->alt should be used instead, but
295 				 * we should probably not touch it at all if it
296 				 * is already >0, because wMaxPacketSize of the
297 				 * audio endpoints seems to be the same for all.
298 				 */
299 			dprintk("changing alternate number on interface %d to %d\n",
300 				dev->ifnum, dev->alt);
301 			usb_set_interface(udev, dev->ifnum, dev->alt);
302 		}
303 
304 		/* Sets volume, mute, etc */
305 		dev->mute = 0;
306 		ret = em28xx_audio_analog_set(dev);
307 		if (ret < 0)
308 			goto err;
309 	}
310 
311 	kref_get(&dev->ref);
312 	dev->adev.users++;
313 	mutex_unlock(&dev->lock);
314 
315 	/* Dynamically adjust the period size */
316 	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
317 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
318 				     dev->adev.period * 95 / 100,
319 				     dev->adev.period * 105 / 100);
320 
321 	dev->adev.capture_pcm_substream = substream;
322 
323 	return 0;
324 err:
325 	mutex_unlock(&dev->lock);
326 
327 	dev_err(&dev->intf->dev,
328 		"Error while configuring em28xx mixer\n");
329 	return ret;
330 }
331 
332 static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
333 {
334 	struct em28xx *dev = snd_pcm_substream_chip(substream);
335 
336 	dprintk("closing device\n");
337 
338 	dev->mute = 1;
339 	mutex_lock(&dev->lock);
340 	dev->adev.users--;
341 	if (atomic_read(&dev->adev.stream_started) > 0) {
342 		atomic_set(&dev->adev.stream_started, 0);
343 		schedule_work(&dev->adev.wq_trigger);
344 	}
345 
346 	em28xx_audio_analog_set(dev);
347 	if (substream->runtime->dma_area) {
348 		dprintk("freeing\n");
349 		vfree(substream->runtime->dma_area);
350 		substream->runtime->dma_area = NULL;
351 	}
352 	mutex_unlock(&dev->lock);
353 	kref_put(&dev->ref, em28xx_free_device);
354 
355 	return 0;
356 }
357 
358 static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
359 					struct snd_pcm_hw_params *hw_params)
360 {
361 	int ret;
362 	struct em28xx *dev = snd_pcm_substream_chip(substream);
363 
364 	if (dev->disconnected)
365 		return -ENODEV;
366 
367 	dprintk("Setting capture parameters\n");
368 
369 	ret = snd_pcm_alloc_vmalloc_buffer(substream,
370 					   params_buffer_bytes(hw_params));
371 	if (ret < 0)
372 		return ret;
373 #if 0
374 	/* TODO: set up em28xx audio chip to deliver the correct audio format,
375 	   current default is 48000hz multiplexed => 96000hz mono
376 	   which shouldn't matter since analogue TV only supports mono */
377 	unsigned int channels, rate, format;
378 
379 	format = params_format(hw_params);
380 	rate = params_rate(hw_params);
381 	channels = params_channels(hw_params);
382 #endif
383 
384 	return 0;
385 }
386 
387 static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
388 {
389 	struct em28xx *dev = snd_pcm_substream_chip(substream);
390 	struct em28xx_audio *adev = &dev->adev;
391 
392 	dprintk("Stop capture, if needed\n");
393 
394 	if (atomic_read(&adev->stream_started) > 0) {
395 		atomic_set(&adev->stream_started, 0);
396 		schedule_work(&adev->wq_trigger);
397 	}
398 
399 	return 0;
400 }
401 
402 static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
403 {
404 	struct em28xx *dev = snd_pcm_substream_chip(substream);
405 
406 	if (dev->disconnected)
407 		return -ENODEV;
408 
409 	dev->adev.hwptr_done_capture = 0;
410 	dev->adev.capture_transfer_done = 0;
411 
412 	return 0;
413 }
414 
415 static void audio_trigger(struct work_struct *work)
416 {
417 	struct em28xx_audio *adev =
418 			    container_of(work, struct em28xx_audio, wq_trigger);
419 	struct em28xx *dev = container_of(adev, struct em28xx, adev);
420 
421 	if (atomic_read(&adev->stream_started)) {
422 		dprintk("starting capture");
423 		em28xx_init_audio_isoc(dev);
424 	} else {
425 		dprintk("stopping capture");
426 		em28xx_deinit_isoc_audio(dev);
427 	}
428 }
429 
430 static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
431 				      int cmd)
432 {
433 	struct em28xx *dev = snd_pcm_substream_chip(substream);
434 	int retval = 0;
435 
436 	if (dev->disconnected)
437 		return -ENODEV;
438 
439 	switch (cmd) {
440 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
441 	case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
442 	case SNDRV_PCM_TRIGGER_START:
443 		atomic_set(&dev->adev.stream_started, 1);
444 		break;
445 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
446 	case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
447 	case SNDRV_PCM_TRIGGER_STOP:
448 		atomic_set(&dev->adev.stream_started, 0);
449 		break;
450 	default:
451 		retval = -EINVAL;
452 	}
453 	schedule_work(&dev->adev.wq_trigger);
454 	return retval;
455 }
456 
457 static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
458 						    *substream)
459 {
460 	unsigned long flags;
461 	struct em28xx *dev;
462 	snd_pcm_uframes_t hwptr_done;
463 
464 	dev = snd_pcm_substream_chip(substream);
465 	if (dev->disconnected)
466 		return SNDRV_PCM_POS_XRUN;
467 
468 	spin_lock_irqsave(&dev->adev.slock, flags);
469 	hwptr_done = dev->adev.hwptr_done_capture;
470 	spin_unlock_irqrestore(&dev->adev.slock, flags);
471 
472 	return hwptr_done;
473 }
474 
475 static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
476 					     unsigned long offset)
477 {
478 	void *pageptr = subs->runtime->dma_area + offset;
479 
480 	return vmalloc_to_page(pageptr);
481 }
482 
483 /*
484  * AC97 volume control support
485  */
486 static int em28xx_vol_info(struct snd_kcontrol *kcontrol,
487 			   struct snd_ctl_elem_info *info)
488 {
489 	struct em28xx *dev = snd_kcontrol_chip(kcontrol);
490 
491 	if (dev->disconnected)
492 		return -ENODEV;
493 
494 	info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
495 	info->count = 2;
496 	info->value.integer.min = 0;
497 	info->value.integer.max = 0x1f;
498 
499 	return 0;
500 }
501 
502 static int em28xx_vol_put(struct snd_kcontrol *kcontrol,
503 			  struct snd_ctl_elem_value *value)
504 {
505 	struct em28xx *dev = snd_kcontrol_chip(kcontrol);
506 	struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
507 	u16 val = (0x1f - (value->value.integer.value[0] & 0x1f)) |
508 		  (0x1f - (value->value.integer.value[1] & 0x1f)) << 8;
509 	int nonblock = 0;
510 	int rc;
511 
512 	if (dev->disconnected)
513 		return -ENODEV;
514 
515 	if (substream)
516 		nonblock = !!(substream->f_flags & O_NONBLOCK);
517 	if (nonblock) {
518 		if (!mutex_trylock(&dev->lock))
519 			return -EAGAIN;
520 	} else
521 		mutex_lock(&dev->lock);
522 	rc = em28xx_read_ac97(dev, kcontrol->private_value);
523 	if (rc < 0)
524 		goto err;
525 
526 	val |= rc & 0x8000;	/* Preserve the mute flag */
527 
528 	rc = em28xx_write_ac97(dev, kcontrol->private_value, val);
529 	if (rc < 0)
530 		goto err;
531 
532 	dprintk("%sleft vol %d, right vol %d (0x%04x) to ac97 volume control 0x%04x\n",
533 		(val & 0x8000) ? "muted " : "",
534 		0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
535 		val, (int)kcontrol->private_value);
536 
537 err:
538 	mutex_unlock(&dev->lock);
539 	return rc;
540 }
541 
542 static int em28xx_vol_get(struct snd_kcontrol *kcontrol,
543 			  struct snd_ctl_elem_value *value)
544 {
545 	struct em28xx *dev = snd_kcontrol_chip(kcontrol);
546 	struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
547 	int nonblock = 0;
548 	int val;
549 
550 	if (dev->disconnected)
551 		return -ENODEV;
552 
553 	if (substream)
554 		nonblock = !!(substream->f_flags & O_NONBLOCK);
555 	if (nonblock) {
556 		if (!mutex_trylock(&dev->lock))
557 			return -EAGAIN;
558 	} else
559 		mutex_lock(&dev->lock);
560 	val = em28xx_read_ac97(dev, kcontrol->private_value);
561 	mutex_unlock(&dev->lock);
562 	if (val < 0)
563 		return val;
564 
565 	dprintk("%sleft vol %d, right vol %d (0x%04x) from ac97 volume control 0x%04x\n",
566 		(val & 0x8000) ? "muted " : "",
567 		0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
568 		val, (int)kcontrol->private_value);
569 
570 	value->value.integer.value[0] = 0x1f - (val & 0x1f);
571 	value->value.integer.value[1] = 0x1f - ((val << 8) & 0x1f);
572 
573 	return 0;
574 }
575 
576 static int em28xx_vol_put_mute(struct snd_kcontrol *kcontrol,
577 			       struct snd_ctl_elem_value *value)
578 {
579 	struct em28xx *dev = snd_kcontrol_chip(kcontrol);
580 	u16 val = value->value.integer.value[0];
581 	struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
582 	int nonblock = 0;
583 	int rc;
584 
585 	if (dev->disconnected)
586 		return -ENODEV;
587 
588 	if (substream)
589 		nonblock = !!(substream->f_flags & O_NONBLOCK);
590 	if (nonblock) {
591 		if (!mutex_trylock(&dev->lock))
592 			return -EAGAIN;
593 	} else
594 		mutex_lock(&dev->lock);
595 	rc = em28xx_read_ac97(dev, kcontrol->private_value);
596 	if (rc < 0)
597 		goto err;
598 
599 	if (val)
600 		rc &= 0x1f1f;
601 	else
602 		rc |= 0x8000;
603 
604 	rc = em28xx_write_ac97(dev, kcontrol->private_value, rc);
605 	if (rc < 0)
606 		goto err;
607 
608 	dprintk("%sleft vol %d, right vol %d (0x%04x) to ac97 volume control 0x%04x\n",
609 		(val & 0x8000) ? "muted " : "",
610 		0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
611 		val, (int)kcontrol->private_value);
612 
613 err:
614 	mutex_unlock(&dev->lock);
615 	return rc;
616 }
617 
618 static int em28xx_vol_get_mute(struct snd_kcontrol *kcontrol,
619 			       struct snd_ctl_elem_value *value)
620 {
621 	struct em28xx *dev = snd_kcontrol_chip(kcontrol);
622 	struct snd_pcm_substream *substream = dev->adev.capture_pcm_substream;
623 	int nonblock = 0;
624 	int val;
625 
626 	if (dev->disconnected)
627 		return -ENODEV;
628 
629 	if (substream)
630 		nonblock = !!(substream->f_flags & O_NONBLOCK);
631 	if (nonblock) {
632 		if (!mutex_trylock(&dev->lock))
633 			return -EAGAIN;
634 	} else
635 		mutex_lock(&dev->lock);
636 	val = em28xx_read_ac97(dev, kcontrol->private_value);
637 	mutex_unlock(&dev->lock);
638 	if (val < 0)
639 		return val;
640 
641 	if (val & 0x8000)
642 		value->value.integer.value[0] = 0;
643 	else
644 		value->value.integer.value[0] = 1;
645 
646 	dprintk("%sleft vol %d, right vol %d (0x%04x) from ac97 volume control 0x%04x\n",
647 		(val & 0x8000) ? "muted " : "",
648 		0x1f - ((val >> 8) & 0x1f), 0x1f - (val & 0x1f),
649 		val, (int)kcontrol->private_value);
650 
651 	return 0;
652 }
653 
654 static const DECLARE_TLV_DB_SCALE(em28xx_db_scale, -3450, 150, 0);
655 
656 static int em28xx_cvol_new(struct snd_card *card, struct em28xx *dev,
657 			   char *name, int id)
658 {
659 	int err;
660 	char ctl_name[44];
661 	struct snd_kcontrol *kctl;
662 	struct snd_kcontrol_new tmp;
663 
664 	memset(&tmp, 0, sizeof(tmp));
665 	tmp.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
666 	tmp.private_value = id,
667 	tmp.name  = ctl_name,
668 
669 	/* Add Mute Control */
670 	sprintf(ctl_name, "%s Switch", name);
671 	tmp.get  = em28xx_vol_get_mute;
672 	tmp.put  = em28xx_vol_put_mute;
673 	tmp.info = snd_ctl_boolean_mono_info;
674 	kctl = snd_ctl_new1(&tmp, dev);
675 	err = snd_ctl_add(card, kctl);
676 	if (err < 0)
677 		return err;
678 	dprintk("Added control %s for ac97 volume control 0x%04x\n",
679 		ctl_name, id);
680 
681 	memset(&tmp, 0, sizeof(tmp));
682 	tmp.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
683 	tmp.private_value = id,
684 	tmp.name  = ctl_name,
685 
686 	/* Add Volume Control */
687 	sprintf(ctl_name, "%s Volume", name);
688 	tmp.get   = em28xx_vol_get;
689 	tmp.put   = em28xx_vol_put;
690 	tmp.info  = em28xx_vol_info;
691 	tmp.tlv.p = em28xx_db_scale,
692 	kctl = snd_ctl_new1(&tmp, dev);
693 	err = snd_ctl_add(card, kctl);
694 	if (err < 0)
695 		return err;
696 	dprintk("Added control %s for ac97 volume control 0x%04x\n",
697 		ctl_name, id);
698 
699 	return 0;
700 }
701 
702 /*
703  * register/unregister code and data
704  */
705 static const struct snd_pcm_ops snd_em28xx_pcm_capture = {
706 	.open      = snd_em28xx_capture_open,
707 	.close     = snd_em28xx_pcm_close,
708 	.ioctl     = snd_pcm_lib_ioctl,
709 	.hw_params = snd_em28xx_hw_capture_params,
710 	.hw_free   = snd_em28xx_hw_capture_free,
711 	.prepare   = snd_em28xx_prepare,
712 	.trigger   = snd_em28xx_capture_trigger,
713 	.pointer   = snd_em28xx_capture_pointer,
714 	.page      = snd_pcm_get_vmalloc_page,
715 };
716 
717 static void em28xx_audio_free_urb(struct em28xx *dev)
718 {
719 	struct usb_device *udev = interface_to_usbdev(dev->intf);
720 	int i;
721 
722 	for (i = 0; i < dev->adev.num_urb; i++) {
723 		struct urb *urb = dev->adev.urb[i];
724 
725 		if (!urb)
726 			continue;
727 
728 		usb_free_coherent(udev, urb->transfer_buffer_length,
729 				  dev->adev.transfer_buffer[i],
730 				  urb->transfer_dma);
731 
732 		usb_free_urb(urb);
733 	}
734 	kfree(dev->adev.urb);
735 	kfree(dev->adev.transfer_buffer);
736 	dev->adev.num_urb = 0;
737 }
738 
739 /* high bandwidth multiplier, as encoded in highspeed endpoint descriptors */
740 static int em28xx_audio_ep_packet_size(struct usb_device *udev,
741 				       struct usb_endpoint_descriptor *e)
742 {
743 	int size = le16_to_cpu(e->wMaxPacketSize);
744 
745 	if (udev->speed == USB_SPEED_HIGH)
746 		return (size & 0x7ff) *  (1 + (((size) >> 11) & 0x03));
747 
748 	return size & 0x7ff;
749 }
750 
751 static int em28xx_audio_urb_init(struct em28xx *dev)
752 {
753 	struct usb_interface *intf;
754 	struct usb_endpoint_descriptor *e, *ep = NULL;
755 	struct usb_device *udev = interface_to_usbdev(dev->intf);
756 	int                 i, ep_size, interval, num_urb, npackets;
757 	int		    urb_size, bytes_per_transfer;
758 	u8 alt;
759 
760 	if (dev->ifnum)
761 		alt = 1;
762 	else
763 		alt = 7;
764 
765 	intf = usb_ifnum_to_if(udev, dev->ifnum);
766 
767 	if (intf->num_altsetting <= alt) {
768 		dev_err(&dev->intf->dev, "alt %d doesn't exist on interface %d\n",
769 			      dev->ifnum, alt);
770 		return -ENODEV;
771 	}
772 
773 	for (i = 0; i < intf->altsetting[alt].desc.bNumEndpoints; i++) {
774 		e = &intf->altsetting[alt].endpoint[i].desc;
775 		if (!usb_endpoint_dir_in(e))
776 			continue;
777 		if (e->bEndpointAddress == EM28XX_EP_AUDIO) {
778 			ep = e;
779 			break;
780 		}
781 	}
782 
783 	if (!ep) {
784 		dev_err(&dev->intf->dev, "Couldn't find an audio endpoint");
785 		return -ENODEV;
786 	}
787 
788 	ep_size = em28xx_audio_ep_packet_size(udev, ep);
789 	interval = 1 << (ep->bInterval - 1);
790 
791 	dev_info(&dev->intf->dev,
792 		 "Endpoint 0x%02x %s on intf %d alt %d interval = %d, size %d\n",
793 		 EM28XX_EP_AUDIO, usb_speed_string(udev->speed),
794 		 dev->ifnum, alt, interval, ep_size);
795 
796 	/* Calculate the number and size of URBs to better fit the audio samples */
797 
798 	/*
799 	 * Estimate the number of bytes per DMA transfer.
800 	 *
801 	 * This is given by the bit rate (for now, only 48000 Hz) multiplied
802 	 * by 2 channels and 2 bytes/sample divided by the number of microframe
803 	 * intervals and by the microframe rate (125 us)
804 	 */
805 	bytes_per_transfer = DIV_ROUND_UP(48000 * 2 * 2, 125 * interval);
806 
807 	/*
808 	 * Estimate the number of transfer URBs. Don't let it go past the
809 	 * maximum number of URBs that is known to be supported by the device.
810 	 */
811 	num_urb = DIV_ROUND_UP(bytes_per_transfer, ep_size);
812 	if (num_urb > EM28XX_MAX_AUDIO_BUFS)
813 		num_urb = EM28XX_MAX_AUDIO_BUFS;
814 
815 	/*
816 	 * Now that we know the number of bytes per transfer and the number of
817 	 * URBs, estimate the typical size of an URB, in order to adjust the
818 	 * minimal number of packets.
819 	 */
820 	urb_size = bytes_per_transfer / num_urb;
821 
822 	/*
823 	 * Now, calculate the amount of audio packets to be filled on each
824 	 * URB. In order to preserve the old behaviour, use a minimal
825 	 * threshold for this value.
826 	 */
827 	npackets = EM28XX_MIN_AUDIO_PACKETS;
828 	if (urb_size > ep_size * npackets)
829 		npackets = DIV_ROUND_UP(urb_size, ep_size);
830 
831 	dev_info(&dev->intf->dev,
832 		 "Number of URBs: %d, with %d packets and %d size\n",
833 		 num_urb, npackets, urb_size);
834 
835 	/* Estimate the bytes per period */
836 	dev->adev.period = urb_size * npackets;
837 
838 	/* Allocate space to store the number of URBs to be used */
839 
840 	dev->adev.transfer_buffer = kcalloc(num_urb,
841 					    sizeof(*dev->adev.transfer_buffer),
842 					    GFP_ATOMIC);
843 	if (!dev->adev.transfer_buffer) {
844 		return -ENOMEM;
845 	}
846 
847 	dev->adev.urb = kcalloc(num_urb, sizeof(*dev->adev.urb), GFP_ATOMIC);
848 	if (!dev->adev.urb) {
849 		kfree(dev->adev.transfer_buffer);
850 		return -ENOMEM;
851 	}
852 
853 	/* Alloc memory for each URB and for each transfer buffer */
854 	dev->adev.num_urb = num_urb;
855 	for (i = 0; i < num_urb; i++) {
856 		struct urb *urb;
857 		int j, k;
858 		void *buf;
859 
860 		urb = usb_alloc_urb(npackets, GFP_ATOMIC);
861 		if (!urb) {
862 			em28xx_audio_free_urb(dev);
863 			return -ENOMEM;
864 		}
865 		dev->adev.urb[i] = urb;
866 
867 		buf = usb_alloc_coherent(udev, npackets * ep_size, GFP_ATOMIC,
868 					 &urb->transfer_dma);
869 		if (!buf) {
870 			dev_err(&dev->intf->dev,
871 				"usb_alloc_coherent failed!\n");
872 			em28xx_audio_free_urb(dev);
873 			return -ENOMEM;
874 		}
875 		dev->adev.transfer_buffer[i] = buf;
876 
877 		urb->dev = udev;
878 		urb->context = dev;
879 		urb->pipe = usb_rcvisocpipe(udev, EM28XX_EP_AUDIO);
880 		urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
881 		urb->transfer_buffer = buf;
882 		urb->interval = interval;
883 		urb->complete = em28xx_audio_isocirq;
884 		urb->number_of_packets = npackets;
885 		urb->transfer_buffer_length = ep_size * npackets;
886 
887 		for (j = k = 0; j < npackets; j++, k += ep_size) {
888 			urb->iso_frame_desc[j].offset = k;
889 			urb->iso_frame_desc[j].length = ep_size;
890 		}
891 	}
892 
893 	return 0;
894 }
895 
896 static int em28xx_audio_init(struct em28xx *dev)
897 {
898 	struct em28xx_audio *adev = &dev->adev;
899 	struct usb_device *udev = interface_to_usbdev(dev->intf);
900 	struct snd_pcm      *pcm;
901 	struct snd_card     *card;
902 	static int          devnr;
903 	int		    err;
904 
905 	if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR) {
906 		/* This device does not support the extension (in this case
907 		   the device is expecting the snd-usb-audio module or
908 		   doesn't have analog audio support at all) */
909 		return 0;
910 	}
911 
912 	dev_info(&dev->intf->dev, "Binding audio extension\n");
913 
914 	kref_get(&dev->ref);
915 
916 	dev_info(&dev->intf->dev,
917 		 "em28xx-audio.c: Copyright (C) 2006 Markus Rechberger\n");
918 	dev_info(&dev->intf->dev,
919 		 "em28xx-audio.c: Copyright (C) 2007-2016 Mauro Carvalho Chehab\n");
920 
921 	err = snd_card_new(&dev->intf->dev, index[devnr], "Em28xx Audio",
922 			   THIS_MODULE, 0, &card);
923 	if (err < 0)
924 		return err;
925 
926 	spin_lock_init(&adev->slock);
927 	adev->sndcard = card;
928 	adev->udev = udev;
929 
930 	err = snd_pcm_new(card, "Em28xx Audio", 0, 0, 1, &pcm);
931 	if (err < 0)
932 		goto card_free;
933 
934 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_em28xx_pcm_capture);
935 	pcm->info_flags = 0;
936 	pcm->private_data = dev;
937 	strcpy(pcm->name, "Empia 28xx Capture");
938 
939 	strcpy(card->driver, "Em28xx-Audio");
940 	strcpy(card->shortname, "Em28xx Audio");
941 	strcpy(card->longname, "Empia Em28xx Audio");
942 
943 	INIT_WORK(&adev->wq_trigger, audio_trigger);
944 
945 	if (dev->audio_mode.ac97 != EM28XX_NO_AC97) {
946 		em28xx_cvol_new(card, dev, "Video", AC97_VIDEO);
947 		em28xx_cvol_new(card, dev, "Line In", AC97_LINE);
948 		em28xx_cvol_new(card, dev, "Phone", AC97_PHONE);
949 		em28xx_cvol_new(card, dev, "Microphone", AC97_MIC);
950 		em28xx_cvol_new(card, dev, "CD", AC97_CD);
951 		em28xx_cvol_new(card, dev, "AUX", AC97_AUX);
952 		em28xx_cvol_new(card, dev, "PCM", AC97_PCM);
953 
954 		em28xx_cvol_new(card, dev, "Master", AC97_MASTER);
955 		em28xx_cvol_new(card, dev, "Line", AC97_HEADPHONE);
956 		em28xx_cvol_new(card, dev, "Mono", AC97_MASTER_MONO);
957 		em28xx_cvol_new(card, dev, "LFE", AC97_CENTER_LFE_MASTER);
958 		em28xx_cvol_new(card, dev, "Surround", AC97_SURROUND_MASTER);
959 	}
960 
961 	err = em28xx_audio_urb_init(dev);
962 	if (err)
963 		goto card_free;
964 
965 	err = snd_card_register(card);
966 	if (err < 0)
967 		goto urb_free;
968 
969 	dev_info(&dev->intf->dev, "Audio extension successfully initialized\n");
970 	return 0;
971 
972 urb_free:
973 	em28xx_audio_free_urb(dev);
974 
975 card_free:
976 	snd_card_free(card);
977 	adev->sndcard = NULL;
978 
979 	return err;
980 }
981 
982 static int em28xx_audio_fini(struct em28xx *dev)
983 {
984 	if (dev == NULL)
985 		return 0;
986 
987 	if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR) {
988 		/* This device does not support the extension (in this case
989 		   the device is expecting the snd-usb-audio module or
990 		   doesn't have analog audio support at all) */
991 		return 0;
992 	}
993 
994 	dev_info(&dev->intf->dev, "Closing audio extension\n");
995 
996 	if (dev->adev.sndcard) {
997 		snd_card_disconnect(dev->adev.sndcard);
998 		flush_work(&dev->adev.wq_trigger);
999 
1000 		em28xx_audio_free_urb(dev);
1001 
1002 		snd_card_free(dev->adev.sndcard);
1003 		dev->adev.sndcard = NULL;
1004 	}
1005 
1006 	kref_put(&dev->ref, em28xx_free_device);
1007 	return 0;
1008 }
1009 
1010 static int em28xx_audio_suspend(struct em28xx *dev)
1011 {
1012 	if (dev == NULL)
1013 		return 0;
1014 
1015 	if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR)
1016 		return 0;
1017 
1018 	dev_info(&dev->intf->dev, "Suspending audio extension\n");
1019 	em28xx_deinit_isoc_audio(dev);
1020 	atomic_set(&dev->adev.stream_started, 0);
1021 	return 0;
1022 }
1023 
1024 static int em28xx_audio_resume(struct em28xx *dev)
1025 {
1026 	if (dev == NULL)
1027 		return 0;
1028 
1029 	if (dev->usb_audio_type != EM28XX_USB_AUDIO_VENDOR)
1030 		return 0;
1031 
1032 	dev_info(&dev->intf->dev, "Resuming audio extension\n");
1033 	/* Nothing to do other than schedule_work() ?? */
1034 	schedule_work(&dev->adev.wq_trigger);
1035 	return 0;
1036 }
1037 
1038 static struct em28xx_ops audio_ops = {
1039 	.id   = EM28XX_AUDIO,
1040 	.name = "Em28xx Audio Extension",
1041 	.init = em28xx_audio_init,
1042 	.fini = em28xx_audio_fini,
1043 	.suspend = em28xx_audio_suspend,
1044 	.resume = em28xx_audio_resume,
1045 };
1046 
1047 static int __init em28xx_alsa_register(void)
1048 {
1049 	return em28xx_register_extension(&audio_ops);
1050 }
1051 
1052 static void __exit em28xx_alsa_unregister(void)
1053 {
1054 	em28xx_unregister_extension(&audio_ops);
1055 }
1056 
1057 MODULE_LICENSE("GPL");
1058 MODULE_AUTHOR("Markus Rechberger <mrechberger@gmail.com>");
1059 MODULE_AUTHOR("Mauro Carvalho Chehab");
1060 MODULE_DESCRIPTION(DRIVER_DESC " - audio interface");
1061 MODULE_VERSION(EM28XX_VERSION);
1062 
1063 module_init(em28xx_alsa_register);
1064 module_exit(em28xx_alsa_unregister);
1065