xref: /openbmc/linux/sound/usb/6fire/pcm.c (revision d0b73b48)
1 /*
2  * Linux driver for TerraTec DMX 6Fire USB
3  *
4  * PCM driver
5  *
6  * Author:	Torsten Schenk <torsten.schenk@zoho.com>
7  * Created:	Jan 01, 2011
8  * Copyright:	(C) Torsten Schenk
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  */
15 
16 #include "pcm.h"
17 #include "chip.h"
18 #include "comm.h"
19 #include "control.h"
20 
21 enum {
22 	OUT_N_CHANNELS = 6, IN_N_CHANNELS = 4
23 };
24 
25 /* keep next two synced with
26  * FW_EP_W_MAX_PACKET_SIZE[] and RATES_MAX_PACKET_SIZE
27  * and CONTROL_RATE_XXX in control.h */
28 static const int rates_in_packet_size[] = { 228, 228, 420, 420, 404, 404 };
29 static const int rates_out_packet_size[] = { 228, 228, 420, 420, 604, 604 };
30 static const int rates[] = { 44100, 48000, 88200, 96000, 176400, 192000 };
31 static const int rates_alsaid[] = {
32 	SNDRV_PCM_RATE_44100, SNDRV_PCM_RATE_48000,
33 	SNDRV_PCM_RATE_88200, SNDRV_PCM_RATE_96000,
34 	SNDRV_PCM_RATE_176400, SNDRV_PCM_RATE_192000 };
35 
36 enum { /* settings for pcm */
37 	OUT_EP = 6, IN_EP = 2, MAX_BUFSIZE = 128 * 1024
38 };
39 
40 enum { /* pcm streaming states */
41 	STREAM_DISABLED, /* no pcm streaming */
42 	STREAM_STARTING, /* pcm streaming requested, waiting to become ready */
43 	STREAM_RUNNING, /* pcm streaming running */
44 	STREAM_STOPPING
45 };
46 
47 static const struct snd_pcm_hardware pcm_hw = {
48 	.info = SNDRV_PCM_INFO_MMAP |
49 		SNDRV_PCM_INFO_INTERLEAVED |
50 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
51 		SNDRV_PCM_INFO_MMAP_VALID |
52 		SNDRV_PCM_INFO_BATCH,
53 
54 	.formats = SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE,
55 
56 	.rates = SNDRV_PCM_RATE_44100 |
57 		SNDRV_PCM_RATE_48000 |
58 		SNDRV_PCM_RATE_88200 |
59 		SNDRV_PCM_RATE_96000 |
60 		SNDRV_PCM_RATE_176400 |
61 		SNDRV_PCM_RATE_192000,
62 
63 	.rate_min = 44100,
64 	.rate_max = 192000,
65 	.channels_min = 1,
66 	.channels_max = 0, /* set in pcm_open, depending on capture/playback */
67 	.buffer_bytes_max = MAX_BUFSIZE,
68 	.period_bytes_min = PCM_N_PACKETS_PER_URB * (PCM_MAX_PACKET_SIZE - 4),
69 	.period_bytes_max = MAX_BUFSIZE,
70 	.periods_min = 2,
71 	.periods_max = 1024
72 };
73 
74 static int usb6fire_pcm_set_rate(struct pcm_runtime *rt)
75 {
76 	int ret;
77 	struct control_runtime *ctrl_rt = rt->chip->control;
78 
79 	ctrl_rt->usb_streaming = false;
80 	ret = ctrl_rt->update_streaming(ctrl_rt);
81 	if (ret < 0) {
82 		snd_printk(KERN_ERR PREFIX "error stopping streaming while "
83 				"setting samplerate %d.\n", rates[rt->rate]);
84 		return ret;
85 	}
86 
87 	ret = ctrl_rt->set_rate(ctrl_rt, rt->rate);
88 	if (ret < 0) {
89 		snd_printk(KERN_ERR PREFIX "error setting samplerate %d.\n",
90 				rates[rt->rate]);
91 		return ret;
92 	}
93 
94 	ret = ctrl_rt->set_channels(ctrl_rt, OUT_N_CHANNELS, IN_N_CHANNELS,
95 			false, false);
96 	if (ret < 0) {
97 		snd_printk(KERN_ERR PREFIX "error initializing channels "
98 				"while setting samplerate %d.\n",
99 				rates[rt->rate]);
100 		return ret;
101 	}
102 
103 	ctrl_rt->usb_streaming = true;
104 	ret = ctrl_rt->update_streaming(ctrl_rt);
105 	if (ret < 0) {
106 		snd_printk(KERN_ERR PREFIX "error starting streaming while "
107 				"setting samplerate %d.\n", rates[rt->rate]);
108 		return ret;
109 	}
110 
111 	rt->in_n_analog = IN_N_CHANNELS;
112 	rt->out_n_analog = OUT_N_CHANNELS;
113 	rt->in_packet_size = rates_in_packet_size[rt->rate];
114 	rt->out_packet_size = rates_out_packet_size[rt->rate];
115 	return 0;
116 }
117 
118 static struct pcm_substream *usb6fire_pcm_get_substream(
119 		struct snd_pcm_substream *alsa_sub)
120 {
121 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
122 
123 	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
124 		return &rt->playback;
125 	else if (alsa_sub->stream == SNDRV_PCM_STREAM_CAPTURE)
126 		return &rt->capture;
127 	snd_printk(KERN_ERR PREFIX "error getting pcm substream slot.\n");
128 	return NULL;
129 }
130 
131 /* call with stream_mutex locked */
132 static void usb6fire_pcm_stream_stop(struct pcm_runtime *rt)
133 {
134 	int i;
135 	struct control_runtime *ctrl_rt = rt->chip->control;
136 
137 	if (rt->stream_state != STREAM_DISABLED) {
138 
139 		rt->stream_state = STREAM_STOPPING;
140 
141 		for (i = 0; i < PCM_N_URBS; i++) {
142 			usb_kill_urb(&rt->in_urbs[i].instance);
143 			usb_kill_urb(&rt->out_urbs[i].instance);
144 		}
145 		ctrl_rt->usb_streaming = false;
146 		ctrl_rt->update_streaming(ctrl_rt);
147 		rt->stream_state = STREAM_DISABLED;
148 	}
149 }
150 
151 /* call with stream_mutex locked */
152 static int usb6fire_pcm_stream_start(struct pcm_runtime *rt)
153 {
154 	int ret;
155 	int i;
156 	int k;
157 	struct usb_iso_packet_descriptor *packet;
158 
159 	if (rt->stream_state == STREAM_DISABLED) {
160 		/* submit our in urbs */
161 		rt->stream_wait_cond = false;
162 		rt->stream_state = STREAM_STARTING;
163 		for (i = 0; i < PCM_N_URBS; i++) {
164 			for (k = 0; k < PCM_N_PACKETS_PER_URB; k++) {
165 				packet = &rt->in_urbs[i].packets[k];
166 				packet->offset = k * rt->in_packet_size;
167 				packet->length = rt->in_packet_size;
168 				packet->actual_length = 0;
169 				packet->status = 0;
170 			}
171 			ret = usb_submit_urb(&rt->in_urbs[i].instance,
172 					GFP_ATOMIC);
173 			if (ret) {
174 				usb6fire_pcm_stream_stop(rt);
175 				return ret;
176 			}
177 		}
178 
179 		/* wait for first out urb to return (sent in in urb handler) */
180 		wait_event_timeout(rt->stream_wait_queue, rt->stream_wait_cond,
181 				HZ);
182 		if (rt->stream_wait_cond)
183 			rt->stream_state = STREAM_RUNNING;
184 		else {
185 			usb6fire_pcm_stream_stop(rt);
186 			return -EIO;
187 		}
188 	}
189 	return 0;
190 }
191 
192 /* call with substream locked */
193 static void usb6fire_pcm_capture(struct pcm_substream *sub, struct pcm_urb *urb)
194 {
195 	int i;
196 	int frame;
197 	int frame_count;
198 	unsigned int total_length = 0;
199 	struct pcm_runtime *rt = snd_pcm_substream_chip(sub->instance);
200 	struct snd_pcm_runtime *alsa_rt = sub->instance->runtime;
201 	u32 *src = NULL;
202 	u32 *dest = (u32 *) (alsa_rt->dma_area + sub->dma_off
203 			* (alsa_rt->frame_bits >> 3));
204 	u32 *dest_end = (u32 *) (alsa_rt->dma_area + alsa_rt->buffer_size
205 			* (alsa_rt->frame_bits >> 3));
206 	int bytes_per_frame = alsa_rt->channels << 2;
207 
208 	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++) {
209 		/* at least 4 header bytes for valid packet.
210 		 * after that: 32 bits per sample for analog channels */
211 		if (urb->packets[i].actual_length > 4)
212 			frame_count = (urb->packets[i].actual_length - 4)
213 					/ (rt->in_n_analog << 2);
214 		else
215 			frame_count = 0;
216 
217 		if (alsa_rt->format == SNDRV_PCM_FORMAT_S24_LE)
218 			src = (u32 *) (urb->buffer + total_length);
219 		else if (alsa_rt->format == SNDRV_PCM_FORMAT_S32_LE)
220 			src = (u32 *) (urb->buffer - 1 + total_length);
221 		else
222 			return;
223 		src++; /* skip leading 4 bytes of every packet */
224 		total_length += urb->packets[i].length;
225 		for (frame = 0; frame < frame_count; frame++) {
226 			memcpy(dest, src, bytes_per_frame);
227 			dest += alsa_rt->channels;
228 			src += rt->in_n_analog;
229 			sub->dma_off++;
230 			sub->period_off++;
231 			if (dest == dest_end) {
232 				sub->dma_off = 0;
233 				dest = (u32 *) alsa_rt->dma_area;
234 			}
235 		}
236 	}
237 }
238 
239 /* call with substream locked */
240 static void usb6fire_pcm_playback(struct pcm_substream *sub,
241 		struct pcm_urb *urb)
242 {
243 	int i;
244 	int frame;
245 	int frame_count;
246 	struct pcm_runtime *rt = snd_pcm_substream_chip(sub->instance);
247 	struct snd_pcm_runtime *alsa_rt = sub->instance->runtime;
248 	u32 *src = (u32 *) (alsa_rt->dma_area + sub->dma_off
249 			* (alsa_rt->frame_bits >> 3));
250 	u32 *src_end = (u32 *) (alsa_rt->dma_area + alsa_rt->buffer_size
251 			* (alsa_rt->frame_bits >> 3));
252 	u32 *dest;
253 	int bytes_per_frame = alsa_rt->channels << 2;
254 
255 	if (alsa_rt->format == SNDRV_PCM_FORMAT_S32_LE)
256 		dest = (u32 *) (urb->buffer - 1);
257 	else if (alsa_rt->format == SNDRV_PCM_FORMAT_S24_LE)
258 		dest = (u32 *) (urb->buffer);
259 	else {
260 		snd_printk(KERN_ERR PREFIX "Unknown sample format.");
261 		return;
262 	}
263 
264 	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++) {
265 		/* at least 4 header bytes for valid packet.
266 		 * after that: 32 bits per sample for analog channels */
267 		if (urb->packets[i].length > 4)
268 			frame_count = (urb->packets[i].length - 4)
269 					/ (rt->out_n_analog << 2);
270 		else
271 			frame_count = 0;
272 		dest++; /* skip leading 4 bytes of every frame */
273 		for (frame = 0; frame < frame_count; frame++) {
274 			memcpy(dest, src, bytes_per_frame);
275 			src += alsa_rt->channels;
276 			dest += rt->out_n_analog;
277 			sub->dma_off++;
278 			sub->period_off++;
279 			if (src == src_end) {
280 				src = (u32 *) alsa_rt->dma_area;
281 				sub->dma_off = 0;
282 			}
283 		}
284 	}
285 }
286 
287 static void usb6fire_pcm_in_urb_handler(struct urb *usb_urb)
288 {
289 	struct pcm_urb *in_urb = usb_urb->context;
290 	struct pcm_urb *out_urb = in_urb->peer;
291 	struct pcm_runtime *rt = in_urb->chip->pcm;
292 	struct pcm_substream *sub;
293 	unsigned long flags;
294 	int total_length = 0;
295 	int frame_count;
296 	int frame;
297 	int channel;
298 	int i;
299 	u8 *dest;
300 
301 	if (usb_urb->status || rt->panic || rt->stream_state == STREAM_STOPPING)
302 		return;
303 	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++)
304 		if (in_urb->packets[i].status) {
305 			rt->panic = true;
306 			return;
307 		}
308 
309 	if (rt->stream_state == STREAM_DISABLED) {
310 		snd_printk(KERN_ERR PREFIX "internal error: "
311 				"stream disabled in in-urb handler.\n");
312 		return;
313 	}
314 
315 	/* receive our capture data */
316 	sub = &rt->capture;
317 	spin_lock_irqsave(&sub->lock, flags);
318 	if (sub->active) {
319 		usb6fire_pcm_capture(sub, in_urb);
320 		if (sub->period_off >= sub->instance->runtime->period_size) {
321 			sub->period_off %= sub->instance->runtime->period_size;
322 			spin_unlock_irqrestore(&sub->lock, flags);
323 			snd_pcm_period_elapsed(sub->instance);
324 		} else
325 			spin_unlock_irqrestore(&sub->lock, flags);
326 	} else
327 		spin_unlock_irqrestore(&sub->lock, flags);
328 
329 	/* setup out urb structure */
330 	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++) {
331 		out_urb->packets[i].offset = total_length;
332 		out_urb->packets[i].length = (in_urb->packets[i].actual_length
333 				- 4) / (rt->in_n_analog << 2)
334 				* (rt->out_n_analog << 2) + 4;
335 		out_urb->packets[i].status = 0;
336 		total_length += out_urb->packets[i].length;
337 	}
338 	memset(out_urb->buffer, 0, total_length);
339 
340 	/* now send our playback data (if a free out urb was found) */
341 	sub = &rt->playback;
342 	spin_lock_irqsave(&sub->lock, flags);
343 	if (sub->active) {
344 		usb6fire_pcm_playback(sub, out_urb);
345 		if (sub->period_off >= sub->instance->runtime->period_size) {
346 			sub->period_off %= sub->instance->runtime->period_size;
347 			spin_unlock_irqrestore(&sub->lock, flags);
348 			snd_pcm_period_elapsed(sub->instance);
349 		} else
350 			spin_unlock_irqrestore(&sub->lock, flags);
351 	} else
352 		spin_unlock_irqrestore(&sub->lock, flags);
353 
354 	/* setup the 4th byte of each sample (0x40 for analog channels) */
355 	dest = out_urb->buffer;
356 	for (i = 0; i < PCM_N_PACKETS_PER_URB; i++)
357 		if (out_urb->packets[i].length >= 4) {
358 			frame_count = (out_urb->packets[i].length - 4)
359 					/ (rt->out_n_analog << 2);
360 			*(dest++) = 0xaa;
361 			*(dest++) = 0xaa;
362 			*(dest++) = frame_count;
363 			*(dest++) = 0x00;
364 			for (frame = 0; frame < frame_count; frame++)
365 				for (channel = 0;
366 						channel < rt->out_n_analog;
367 						channel++) {
368 					dest += 3; /* skip sample data */
369 					*(dest++) = 0x40;
370 				}
371 		}
372 	usb_submit_urb(&out_urb->instance, GFP_ATOMIC);
373 	usb_submit_urb(&in_urb->instance, GFP_ATOMIC);
374 }
375 
376 static void usb6fire_pcm_out_urb_handler(struct urb *usb_urb)
377 {
378 	struct pcm_urb *urb = usb_urb->context;
379 	struct pcm_runtime *rt = urb->chip->pcm;
380 
381 	if (rt->stream_state == STREAM_STARTING) {
382 		rt->stream_wait_cond = true;
383 		wake_up(&rt->stream_wait_queue);
384 	}
385 }
386 
387 static int usb6fire_pcm_open(struct snd_pcm_substream *alsa_sub)
388 {
389 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
390 	struct pcm_substream *sub = NULL;
391 	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
392 
393 	if (rt->panic)
394 		return -EPIPE;
395 
396 	mutex_lock(&rt->stream_mutex);
397 	alsa_rt->hw = pcm_hw;
398 
399 	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK) {
400 		if (rt->rate < ARRAY_SIZE(rates))
401 			alsa_rt->hw.rates = rates_alsaid[rt->rate];
402 		alsa_rt->hw.channels_max = OUT_N_CHANNELS;
403 		sub = &rt->playback;
404 	} else if (alsa_sub->stream == SNDRV_PCM_STREAM_CAPTURE) {
405 		if (rt->rate < ARRAY_SIZE(rates))
406 			alsa_rt->hw.rates = rates_alsaid[rt->rate];
407 		alsa_rt->hw.channels_max = IN_N_CHANNELS;
408 		sub = &rt->capture;
409 	}
410 
411 	if (!sub) {
412 		mutex_unlock(&rt->stream_mutex);
413 		snd_printk(KERN_ERR PREFIX "invalid stream type.\n");
414 		return -EINVAL;
415 	}
416 
417 	sub->instance = alsa_sub;
418 	sub->active = false;
419 	mutex_unlock(&rt->stream_mutex);
420 	return 0;
421 }
422 
423 static int usb6fire_pcm_close(struct snd_pcm_substream *alsa_sub)
424 {
425 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
426 	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
427 	unsigned long flags;
428 
429 	if (rt->panic)
430 		return 0;
431 
432 	mutex_lock(&rt->stream_mutex);
433 	if (sub) {
434 		/* deactivate substream */
435 		spin_lock_irqsave(&sub->lock, flags);
436 		sub->instance = NULL;
437 		sub->active = false;
438 		spin_unlock_irqrestore(&sub->lock, flags);
439 
440 		/* all substreams closed? if so, stop streaming */
441 		if (!rt->playback.instance && !rt->capture.instance) {
442 			usb6fire_pcm_stream_stop(rt);
443 			rt->rate = ARRAY_SIZE(rates);
444 		}
445 	}
446 	mutex_unlock(&rt->stream_mutex);
447 	return 0;
448 }
449 
450 static int usb6fire_pcm_hw_params(struct snd_pcm_substream *alsa_sub,
451 		struct snd_pcm_hw_params *hw_params)
452 {
453 	return snd_pcm_lib_malloc_pages(alsa_sub,
454 			params_buffer_bytes(hw_params));
455 }
456 
457 static int usb6fire_pcm_hw_free(struct snd_pcm_substream *alsa_sub)
458 {
459 	return snd_pcm_lib_free_pages(alsa_sub);
460 }
461 
462 static int usb6fire_pcm_prepare(struct snd_pcm_substream *alsa_sub)
463 {
464 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
465 	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
466 	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
467 	int ret;
468 
469 	if (rt->panic)
470 		return -EPIPE;
471 	if (!sub)
472 		return -ENODEV;
473 
474 	mutex_lock(&rt->stream_mutex);
475 	sub->dma_off = 0;
476 	sub->period_off = 0;
477 
478 	if (rt->stream_state == STREAM_DISABLED) {
479 		for (rt->rate = 0; rt->rate < ARRAY_SIZE(rates); rt->rate++)
480 			if (alsa_rt->rate == rates[rt->rate])
481 				break;
482 		if (rt->rate == ARRAY_SIZE(rates)) {
483 			mutex_unlock(&rt->stream_mutex);
484 			snd_printk("invalid rate %d in prepare.\n",
485 					alsa_rt->rate);
486 			return -EINVAL;
487 		}
488 
489 		ret = usb6fire_pcm_set_rate(rt);
490 		if (ret) {
491 			mutex_unlock(&rt->stream_mutex);
492 			return ret;
493 		}
494 		ret = usb6fire_pcm_stream_start(rt);
495 		if (ret) {
496 			mutex_unlock(&rt->stream_mutex);
497 			snd_printk(KERN_ERR PREFIX
498 					"could not start pcm stream.\n");
499 			return ret;
500 		}
501 	}
502 	mutex_unlock(&rt->stream_mutex);
503 	return 0;
504 }
505 
506 static int usb6fire_pcm_trigger(struct snd_pcm_substream *alsa_sub, int cmd)
507 {
508 	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
509 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
510 	unsigned long flags;
511 
512 	if (rt->panic)
513 		return -EPIPE;
514 	if (!sub)
515 		return -ENODEV;
516 
517 	switch (cmd) {
518 	case SNDRV_PCM_TRIGGER_START:
519 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
520 		spin_lock_irqsave(&sub->lock, flags);
521 		sub->active = true;
522 		spin_unlock_irqrestore(&sub->lock, flags);
523 		return 0;
524 
525 	case SNDRV_PCM_TRIGGER_STOP:
526 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
527 		spin_lock_irqsave(&sub->lock, flags);
528 		sub->active = false;
529 		spin_unlock_irqrestore(&sub->lock, flags);
530 		return 0;
531 
532 	default:
533 		return -EINVAL;
534 	}
535 }
536 
537 static snd_pcm_uframes_t usb6fire_pcm_pointer(
538 		struct snd_pcm_substream *alsa_sub)
539 {
540 	struct pcm_substream *sub = usb6fire_pcm_get_substream(alsa_sub);
541 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
542 	unsigned long flags;
543 	snd_pcm_uframes_t ret;
544 
545 	if (rt->panic || !sub)
546 		return SNDRV_PCM_STATE_XRUN;
547 
548 	spin_lock_irqsave(&sub->lock, flags);
549 	ret = sub->dma_off;
550 	spin_unlock_irqrestore(&sub->lock, flags);
551 	return ret;
552 }
553 
554 static struct snd_pcm_ops pcm_ops = {
555 	.open = usb6fire_pcm_open,
556 	.close = usb6fire_pcm_close,
557 	.ioctl = snd_pcm_lib_ioctl,
558 	.hw_params = usb6fire_pcm_hw_params,
559 	.hw_free = usb6fire_pcm_hw_free,
560 	.prepare = usb6fire_pcm_prepare,
561 	.trigger = usb6fire_pcm_trigger,
562 	.pointer = usb6fire_pcm_pointer,
563 };
564 
565 static void usb6fire_pcm_init_urb(struct pcm_urb *urb,
566 				  struct sfire_chip *chip, bool in, int ep,
567 				  void (*handler)(struct urb *))
568 {
569 	urb->chip = chip;
570 	usb_init_urb(&urb->instance);
571 	urb->instance.transfer_buffer = urb->buffer;
572 	urb->instance.transfer_buffer_length =
573 			PCM_N_PACKETS_PER_URB * PCM_MAX_PACKET_SIZE;
574 	urb->instance.dev = chip->dev;
575 	urb->instance.pipe = in ? usb_rcvisocpipe(chip->dev, ep)
576 			: usb_sndisocpipe(chip->dev, ep);
577 	urb->instance.interval = 1;
578 	urb->instance.transfer_flags = URB_ISO_ASAP;
579 	urb->instance.complete = handler;
580 	urb->instance.context = urb;
581 	urb->instance.number_of_packets = PCM_N_PACKETS_PER_URB;
582 }
583 
584 int usb6fire_pcm_init(struct sfire_chip *chip)
585 {
586 	int i;
587 	int ret;
588 	struct snd_pcm *pcm;
589 	struct pcm_runtime *rt =
590 			kzalloc(sizeof(struct pcm_runtime), GFP_KERNEL);
591 
592 	if (!rt)
593 		return -ENOMEM;
594 
595 	rt->chip = chip;
596 	rt->stream_state = STREAM_DISABLED;
597 	rt->rate = ARRAY_SIZE(rates);
598 	init_waitqueue_head(&rt->stream_wait_queue);
599 	mutex_init(&rt->stream_mutex);
600 
601 	spin_lock_init(&rt->playback.lock);
602 	spin_lock_init(&rt->capture.lock);
603 
604 	for (i = 0; i < PCM_N_URBS; i++) {
605 		usb6fire_pcm_init_urb(&rt->in_urbs[i], chip, true, IN_EP,
606 				usb6fire_pcm_in_urb_handler);
607 		usb6fire_pcm_init_urb(&rt->out_urbs[i], chip, false, OUT_EP,
608 				usb6fire_pcm_out_urb_handler);
609 
610 		rt->in_urbs[i].peer = &rt->out_urbs[i];
611 		rt->out_urbs[i].peer = &rt->in_urbs[i];
612 	}
613 
614 	ret = snd_pcm_new(chip->card, "DMX6FireUSB", 0, 1, 1, &pcm);
615 	if (ret < 0) {
616 		kfree(rt);
617 		snd_printk(KERN_ERR PREFIX "cannot create pcm instance.\n");
618 		return ret;
619 	}
620 
621 	pcm->private_data = rt;
622 	strcpy(pcm->name, "DMX 6Fire USB");
623 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &pcm_ops);
624 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &pcm_ops);
625 
626 	ret = snd_pcm_lib_preallocate_pages_for_all(pcm,
627 			SNDRV_DMA_TYPE_CONTINUOUS,
628 			snd_dma_continuous_data(GFP_KERNEL),
629 			MAX_BUFSIZE, MAX_BUFSIZE);
630 	if (ret) {
631 		kfree(rt);
632 		snd_printk(KERN_ERR PREFIX
633 				"error preallocating pcm buffers.\n");
634 		return ret;
635 	}
636 	rt->instance = pcm;
637 
638 	chip->pcm = rt;
639 	return 0;
640 }
641 
642 void usb6fire_pcm_abort(struct sfire_chip *chip)
643 {
644 	struct pcm_runtime *rt = chip->pcm;
645 	int i;
646 
647 	if (rt) {
648 		rt->panic = true;
649 
650 		if (rt->playback.instance)
651 			snd_pcm_stop(rt->playback.instance,
652 					SNDRV_PCM_STATE_XRUN);
653 		if (rt->capture.instance)
654 			snd_pcm_stop(rt->capture.instance,
655 					SNDRV_PCM_STATE_XRUN);
656 
657 		for (i = 0; i < PCM_N_URBS; i++) {
658 			usb_poison_urb(&rt->in_urbs[i].instance);
659 			usb_poison_urb(&rt->out_urbs[i].instance);
660 		}
661 
662 	}
663 }
664 
665 void usb6fire_pcm_destroy(struct sfire_chip *chip)
666 {
667 	kfree(chip->pcm);
668 	chip->pcm = NULL;
669 }
670