xref: /openbmc/linux/sound/usb/hiface/pcm.c (revision 8bd1369b)
1 /*
2  * Linux driver for M2Tech hiFace compatible devices
3  *
4  * Copyright 2012-2013 (C) M2TECH S.r.l and Amarula Solutions B.V.
5  *
6  * Authors:  Michael Trimarchi <michael@amarulasolutions.com>
7  *           Antonio Ospite <ao2@amarulasolutions.com>
8  *
9  * The driver is based on the work done in TerraTec DMX 6Fire USB
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  */
16 
17 #include <linux/slab.h>
18 #include <sound/pcm.h>
19 
20 #include "pcm.h"
21 #include "chip.h"
22 
23 #define OUT_EP          0x2
24 #define PCM_N_URBS      8
25 #define PCM_PACKET_SIZE 4096
26 #define PCM_BUFFER_SIZE (2 * PCM_N_URBS * PCM_PACKET_SIZE)
27 
28 struct pcm_urb {
29 	struct hiface_chip *chip;
30 
31 	struct urb instance;
32 	struct usb_anchor submitted;
33 	u8 *buffer;
34 };
35 
36 struct pcm_substream {
37 	spinlock_t lock;
38 	struct snd_pcm_substream *instance;
39 
40 	bool active;
41 	snd_pcm_uframes_t dma_off;    /* current position in alsa dma_area */
42 	snd_pcm_uframes_t period_off; /* current position in current period */
43 };
44 
45 enum { /* pcm streaming states */
46 	STREAM_DISABLED, /* no pcm streaming */
47 	STREAM_STARTING, /* pcm streaming requested, waiting to become ready */
48 	STREAM_RUNNING,  /* pcm streaming running */
49 	STREAM_STOPPING
50 };
51 
52 struct pcm_runtime {
53 	struct hiface_chip *chip;
54 	struct snd_pcm *instance;
55 
56 	struct pcm_substream playback;
57 	bool panic; /* if set driver won't do anymore pcm on device */
58 
59 	struct pcm_urb out_urbs[PCM_N_URBS];
60 
61 	struct mutex stream_mutex;
62 	u8 stream_state; /* one of STREAM_XXX */
63 	u8 extra_freq;
64 	wait_queue_head_t stream_wait_queue;
65 	bool stream_wait_cond;
66 };
67 
68 static const unsigned int rates[] = { 44100, 48000, 88200, 96000, 176400, 192000,
69 				      352800, 384000 };
70 static const struct snd_pcm_hw_constraint_list constraints_extra_rates = {
71 	.count = ARRAY_SIZE(rates),
72 	.list = rates,
73 	.mask = 0,
74 };
75 
76 static const struct snd_pcm_hardware pcm_hw = {
77 	.info = SNDRV_PCM_INFO_MMAP |
78 		SNDRV_PCM_INFO_INTERLEAVED |
79 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
80 		SNDRV_PCM_INFO_PAUSE |
81 		SNDRV_PCM_INFO_MMAP_VALID |
82 		SNDRV_PCM_INFO_BATCH,
83 
84 	.formats = SNDRV_PCM_FMTBIT_S32_LE,
85 
86 	.rates = SNDRV_PCM_RATE_44100 |
87 		SNDRV_PCM_RATE_48000 |
88 		SNDRV_PCM_RATE_88200 |
89 		SNDRV_PCM_RATE_96000 |
90 		SNDRV_PCM_RATE_176400 |
91 		SNDRV_PCM_RATE_192000,
92 
93 	.rate_min = 44100,
94 	.rate_max = 192000, /* changes in hiface_pcm_open to support extra rates */
95 	.channels_min = 2,
96 	.channels_max = 2,
97 	.buffer_bytes_max = PCM_BUFFER_SIZE,
98 	.period_bytes_min = PCM_PACKET_SIZE,
99 	.period_bytes_max = PCM_BUFFER_SIZE,
100 	.periods_min = 2,
101 	.periods_max = 1024
102 };
103 
104 /* message values used to change the sample rate */
105 #define HIFACE_SET_RATE_REQUEST 0xb0
106 
107 #define HIFACE_RATE_44100  0x43
108 #define HIFACE_RATE_48000  0x4b
109 #define HIFACE_RATE_88200  0x42
110 #define HIFACE_RATE_96000  0x4a
111 #define HIFACE_RATE_176400 0x40
112 #define HIFACE_RATE_192000 0x48
113 #define HIFACE_RATE_352800 0x58
114 #define HIFACE_RATE_384000 0x68
115 
116 static int hiface_pcm_set_rate(struct pcm_runtime *rt, unsigned int rate)
117 {
118 	struct usb_device *device = rt->chip->dev;
119 	u16 rate_value;
120 	int ret;
121 
122 	/* We are already sure that the rate is supported here thanks to
123 	 * ALSA constraints
124 	 */
125 	switch (rate) {
126 	case 44100:
127 		rate_value = HIFACE_RATE_44100;
128 		break;
129 	case 48000:
130 		rate_value = HIFACE_RATE_48000;
131 		break;
132 	case 88200:
133 		rate_value = HIFACE_RATE_88200;
134 		break;
135 	case 96000:
136 		rate_value = HIFACE_RATE_96000;
137 		break;
138 	case 176400:
139 		rate_value = HIFACE_RATE_176400;
140 		break;
141 	case 192000:
142 		rate_value = HIFACE_RATE_192000;
143 		break;
144 	case 352800:
145 		rate_value = HIFACE_RATE_352800;
146 		break;
147 	case 384000:
148 		rate_value = HIFACE_RATE_384000;
149 		break;
150 	default:
151 		dev_err(&device->dev, "Unsupported rate %d\n", rate);
152 		return -EINVAL;
153 	}
154 
155 	/*
156 	 * USBIO: Vendor 0xb0(wValue=0x0043, wIndex=0x0000)
157 	 * 43 b0 43 00 00 00 00 00
158 	 * USBIO: Vendor 0xb0(wValue=0x004b, wIndex=0x0000)
159 	 * 43 b0 4b 00 00 00 00 00
160 	 * This control message doesn't have any ack from the
161 	 * other side
162 	 */
163 	ret = usb_control_msg(device, usb_sndctrlpipe(device, 0),
164 			      HIFACE_SET_RATE_REQUEST,
165 			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
166 			      rate_value, 0, NULL, 0, 100);
167 	if (ret < 0) {
168 		dev_err(&device->dev, "Error setting samplerate %d.\n", rate);
169 		return ret;
170 	}
171 
172 	return 0;
173 }
174 
175 static struct pcm_substream *hiface_pcm_get_substream(struct snd_pcm_substream
176 						      *alsa_sub)
177 {
178 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
179 	struct device *device = &rt->chip->dev->dev;
180 
181 	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
182 		return &rt->playback;
183 
184 	dev_err(device, "Error getting pcm substream slot.\n");
185 	return NULL;
186 }
187 
188 /* call with stream_mutex locked */
189 static void hiface_pcm_stream_stop(struct pcm_runtime *rt)
190 {
191 	int i, time;
192 
193 	if (rt->stream_state != STREAM_DISABLED) {
194 		rt->stream_state = STREAM_STOPPING;
195 
196 		for (i = 0; i < PCM_N_URBS; i++) {
197 			time = usb_wait_anchor_empty_timeout(
198 					&rt->out_urbs[i].submitted, 100);
199 			if (!time)
200 				usb_kill_anchored_urbs(
201 					&rt->out_urbs[i].submitted);
202 			usb_kill_urb(&rt->out_urbs[i].instance);
203 		}
204 
205 		rt->stream_state = STREAM_DISABLED;
206 	}
207 }
208 
209 /* call with stream_mutex locked */
210 static int hiface_pcm_stream_start(struct pcm_runtime *rt)
211 {
212 	int ret = 0;
213 	int i;
214 
215 	if (rt->stream_state == STREAM_DISABLED) {
216 
217 		/* reset panic state when starting a new stream */
218 		rt->panic = false;
219 
220 		/* submit our out urbs zero init */
221 		rt->stream_state = STREAM_STARTING;
222 		for (i = 0; i < PCM_N_URBS; i++) {
223 			memset(rt->out_urbs[i].buffer, 0, PCM_PACKET_SIZE);
224 			usb_anchor_urb(&rt->out_urbs[i].instance,
225 				       &rt->out_urbs[i].submitted);
226 			ret = usb_submit_urb(&rt->out_urbs[i].instance,
227 					     GFP_ATOMIC);
228 			if (ret) {
229 				hiface_pcm_stream_stop(rt);
230 				return ret;
231 			}
232 		}
233 
234 		/* wait for first out urb to return (sent in in urb handler) */
235 		wait_event_timeout(rt->stream_wait_queue, rt->stream_wait_cond,
236 				   HZ);
237 		if (rt->stream_wait_cond) {
238 			struct device *device = &rt->chip->dev->dev;
239 			dev_dbg(device, "%s: Stream is running wakeup event\n",
240 				 __func__);
241 			rt->stream_state = STREAM_RUNNING;
242 		} else {
243 			hiface_pcm_stream_stop(rt);
244 			return -EIO;
245 		}
246 	}
247 	return ret;
248 }
249 
250 /* The hardware wants word-swapped 32-bit values */
251 static void memcpy_swahw32(u8 *dest, u8 *src, unsigned int n)
252 {
253 	unsigned int i;
254 
255 	for (i = 0; i < n / 4; i++)
256 		((u32 *)dest)[i] = swahw32(((u32 *)src)[i]);
257 }
258 
259 /* call with substream locked */
260 /* returns true if a period elapsed */
261 static bool hiface_pcm_playback(struct pcm_substream *sub, struct pcm_urb *urb)
262 {
263 	struct snd_pcm_runtime *alsa_rt = sub->instance->runtime;
264 	struct device *device = &urb->chip->dev->dev;
265 	u8 *source;
266 	unsigned int pcm_buffer_size;
267 
268 	WARN_ON(alsa_rt->format != SNDRV_PCM_FORMAT_S32_LE);
269 
270 	pcm_buffer_size = snd_pcm_lib_buffer_bytes(sub->instance);
271 
272 	if (sub->dma_off + PCM_PACKET_SIZE <= pcm_buffer_size) {
273 		dev_dbg(device, "%s: (1) buffer_size %#x dma_offset %#x\n", __func__,
274 			 (unsigned int) pcm_buffer_size,
275 			 (unsigned int) sub->dma_off);
276 
277 		source = alsa_rt->dma_area + sub->dma_off;
278 		memcpy_swahw32(urb->buffer, source, PCM_PACKET_SIZE);
279 	} else {
280 		/* wrap around at end of ring buffer */
281 		unsigned int len;
282 
283 		dev_dbg(device, "%s: (2) buffer_size %#x dma_offset %#x\n", __func__,
284 			 (unsigned int) pcm_buffer_size,
285 			 (unsigned int) sub->dma_off);
286 
287 		len = pcm_buffer_size - sub->dma_off;
288 
289 		source = alsa_rt->dma_area + sub->dma_off;
290 		memcpy_swahw32(urb->buffer, source, len);
291 
292 		source = alsa_rt->dma_area;
293 		memcpy_swahw32(urb->buffer + len, source,
294 			       PCM_PACKET_SIZE - len);
295 	}
296 	sub->dma_off += PCM_PACKET_SIZE;
297 	if (sub->dma_off >= pcm_buffer_size)
298 		sub->dma_off -= pcm_buffer_size;
299 
300 	sub->period_off += PCM_PACKET_SIZE;
301 	if (sub->period_off >= alsa_rt->period_size) {
302 		sub->period_off %= alsa_rt->period_size;
303 		return true;
304 	}
305 	return false;
306 }
307 
308 static void hiface_pcm_out_urb_handler(struct urb *usb_urb)
309 {
310 	struct pcm_urb *out_urb = usb_urb->context;
311 	struct pcm_runtime *rt = out_urb->chip->pcm;
312 	struct pcm_substream *sub;
313 	bool do_period_elapsed = false;
314 	unsigned long flags;
315 	int ret;
316 
317 	if (rt->panic || rt->stream_state == STREAM_STOPPING)
318 		return;
319 
320 	if (unlikely(usb_urb->status == -ENOENT ||	/* unlinked */
321 		     usb_urb->status == -ENODEV ||	/* device removed */
322 		     usb_urb->status == -ECONNRESET ||	/* unlinked */
323 		     usb_urb->status == -ESHUTDOWN)) {	/* device disabled */
324 		goto out_fail;
325 	}
326 
327 	if (rt->stream_state == STREAM_STARTING) {
328 		rt->stream_wait_cond = true;
329 		wake_up(&rt->stream_wait_queue);
330 	}
331 
332 	/* now send our playback data (if a free out urb was found) */
333 	sub = &rt->playback;
334 	spin_lock_irqsave(&sub->lock, flags);
335 	if (sub->active)
336 		do_period_elapsed = hiface_pcm_playback(sub, out_urb);
337 	else
338 		memset(out_urb->buffer, 0, PCM_PACKET_SIZE);
339 
340 	spin_unlock_irqrestore(&sub->lock, flags);
341 
342 	if (do_period_elapsed)
343 		snd_pcm_period_elapsed(sub->instance);
344 
345 	ret = usb_submit_urb(&out_urb->instance, GFP_ATOMIC);
346 	if (ret < 0)
347 		goto out_fail;
348 
349 	return;
350 
351 out_fail:
352 	rt->panic = true;
353 }
354 
355 static int hiface_pcm_open(struct snd_pcm_substream *alsa_sub)
356 {
357 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
358 	struct pcm_substream *sub = NULL;
359 	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
360 	int ret;
361 
362 	if (rt->panic)
363 		return -EPIPE;
364 
365 	mutex_lock(&rt->stream_mutex);
366 	alsa_rt->hw = pcm_hw;
367 
368 	if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
369 		sub = &rt->playback;
370 
371 	if (!sub) {
372 		struct device *device = &rt->chip->dev->dev;
373 		mutex_unlock(&rt->stream_mutex);
374 		dev_err(device, "Invalid stream type\n");
375 		return -EINVAL;
376 	}
377 
378 	if (rt->extra_freq) {
379 		alsa_rt->hw.rates |= SNDRV_PCM_RATE_KNOT;
380 		alsa_rt->hw.rate_max = 384000;
381 
382 		/* explicit constraints needed as we added SNDRV_PCM_RATE_KNOT */
383 		ret = snd_pcm_hw_constraint_list(alsa_sub->runtime, 0,
384 						 SNDRV_PCM_HW_PARAM_RATE,
385 						 &constraints_extra_rates);
386 		if (ret < 0) {
387 			mutex_unlock(&rt->stream_mutex);
388 			return ret;
389 		}
390 	}
391 
392 	sub->instance = alsa_sub;
393 	sub->active = false;
394 	mutex_unlock(&rt->stream_mutex);
395 	return 0;
396 }
397 
398 static int hiface_pcm_close(struct snd_pcm_substream *alsa_sub)
399 {
400 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
401 	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
402 	unsigned long flags;
403 
404 	if (rt->panic)
405 		return 0;
406 
407 	mutex_lock(&rt->stream_mutex);
408 	if (sub) {
409 		hiface_pcm_stream_stop(rt);
410 
411 		/* deactivate substream */
412 		spin_lock_irqsave(&sub->lock, flags);
413 		sub->instance = NULL;
414 		sub->active = false;
415 		spin_unlock_irqrestore(&sub->lock, flags);
416 
417 	}
418 	mutex_unlock(&rt->stream_mutex);
419 	return 0;
420 }
421 
422 static int hiface_pcm_hw_params(struct snd_pcm_substream *alsa_sub,
423 				struct snd_pcm_hw_params *hw_params)
424 {
425 	return snd_pcm_lib_alloc_vmalloc_buffer(alsa_sub,
426 						params_buffer_bytes(hw_params));
427 }
428 
429 static int hiface_pcm_hw_free(struct snd_pcm_substream *alsa_sub)
430 {
431 	return snd_pcm_lib_free_vmalloc_buffer(alsa_sub);
432 }
433 
434 static int hiface_pcm_prepare(struct snd_pcm_substream *alsa_sub)
435 {
436 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
437 	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
438 	struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
439 	int ret;
440 
441 	if (rt->panic)
442 		return -EPIPE;
443 	if (!sub)
444 		return -ENODEV;
445 
446 	mutex_lock(&rt->stream_mutex);
447 
448 	hiface_pcm_stream_stop(rt);
449 
450 	sub->dma_off = 0;
451 	sub->period_off = 0;
452 
453 	if (rt->stream_state == STREAM_DISABLED) {
454 
455 		ret = hiface_pcm_set_rate(rt, alsa_rt->rate);
456 		if (ret) {
457 			mutex_unlock(&rt->stream_mutex);
458 			return ret;
459 		}
460 		ret = hiface_pcm_stream_start(rt);
461 		if (ret) {
462 			mutex_unlock(&rt->stream_mutex);
463 			return ret;
464 		}
465 	}
466 	mutex_unlock(&rt->stream_mutex);
467 	return 0;
468 }
469 
470 static int hiface_pcm_trigger(struct snd_pcm_substream *alsa_sub, int cmd)
471 {
472 	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
473 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
474 
475 	if (rt->panic)
476 		return -EPIPE;
477 	if (!sub)
478 		return -ENODEV;
479 
480 	switch (cmd) {
481 	case SNDRV_PCM_TRIGGER_START:
482 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
483 		spin_lock_irq(&sub->lock);
484 		sub->active = true;
485 		spin_unlock_irq(&sub->lock);
486 		return 0;
487 
488 	case SNDRV_PCM_TRIGGER_STOP:
489 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
490 		spin_lock_irq(&sub->lock);
491 		sub->active = false;
492 		spin_unlock_irq(&sub->lock);
493 		return 0;
494 
495 	default:
496 		return -EINVAL;
497 	}
498 }
499 
500 static snd_pcm_uframes_t hiface_pcm_pointer(struct snd_pcm_substream *alsa_sub)
501 {
502 	struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
503 	struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
504 	unsigned long flags;
505 	snd_pcm_uframes_t dma_offset;
506 
507 	if (rt->panic || !sub)
508 		return SNDRV_PCM_POS_XRUN;
509 
510 	spin_lock_irqsave(&sub->lock, flags);
511 	dma_offset = sub->dma_off;
512 	spin_unlock_irqrestore(&sub->lock, flags);
513 	return bytes_to_frames(alsa_sub->runtime, dma_offset);
514 }
515 
516 static const struct snd_pcm_ops pcm_ops = {
517 	.open = hiface_pcm_open,
518 	.close = hiface_pcm_close,
519 	.ioctl = snd_pcm_lib_ioctl,
520 	.hw_params = hiface_pcm_hw_params,
521 	.hw_free = hiface_pcm_hw_free,
522 	.prepare = hiface_pcm_prepare,
523 	.trigger = hiface_pcm_trigger,
524 	.pointer = hiface_pcm_pointer,
525 	.page = snd_pcm_lib_get_vmalloc_page,
526 	.mmap = snd_pcm_lib_mmap_vmalloc,
527 };
528 
529 static int hiface_pcm_init_urb(struct pcm_urb *urb,
530 			       struct hiface_chip *chip,
531 			       unsigned int ep,
532 			       void (*handler)(struct urb *))
533 {
534 	urb->chip = chip;
535 	usb_init_urb(&urb->instance);
536 
537 	urb->buffer = kzalloc(PCM_PACKET_SIZE, GFP_KERNEL);
538 	if (!urb->buffer)
539 		return -ENOMEM;
540 
541 	usb_fill_bulk_urb(&urb->instance, chip->dev,
542 			  usb_sndbulkpipe(chip->dev, ep), (void *)urb->buffer,
543 			  PCM_PACKET_SIZE, handler, urb);
544 	if (usb_urb_ep_type_check(&urb->instance))
545 		return -EINVAL;
546 	init_usb_anchor(&urb->submitted);
547 
548 	return 0;
549 }
550 
551 void hiface_pcm_abort(struct hiface_chip *chip)
552 {
553 	struct pcm_runtime *rt = chip->pcm;
554 
555 	if (rt) {
556 		rt->panic = true;
557 
558 		mutex_lock(&rt->stream_mutex);
559 		hiface_pcm_stream_stop(rt);
560 		mutex_unlock(&rt->stream_mutex);
561 	}
562 }
563 
564 static void hiface_pcm_destroy(struct hiface_chip *chip)
565 {
566 	struct pcm_runtime *rt = chip->pcm;
567 	int i;
568 
569 	for (i = 0; i < PCM_N_URBS; i++)
570 		kfree(rt->out_urbs[i].buffer);
571 
572 	kfree(chip->pcm);
573 	chip->pcm = NULL;
574 }
575 
576 static void hiface_pcm_free(struct snd_pcm *pcm)
577 {
578 	struct pcm_runtime *rt = pcm->private_data;
579 
580 	if (rt)
581 		hiface_pcm_destroy(rt->chip);
582 }
583 
584 int hiface_pcm_init(struct hiface_chip *chip, u8 extra_freq)
585 {
586 	int i;
587 	int ret;
588 	struct snd_pcm *pcm;
589 	struct pcm_runtime *rt;
590 
591 	rt = kzalloc(sizeof(*rt), GFP_KERNEL);
592 	if (!rt)
593 		return -ENOMEM;
594 
595 	rt->chip = chip;
596 	rt->stream_state = STREAM_DISABLED;
597 	if (extra_freq)
598 		rt->extra_freq = 1;
599 
600 	init_waitqueue_head(&rt->stream_wait_queue);
601 	mutex_init(&rt->stream_mutex);
602 	spin_lock_init(&rt->playback.lock);
603 
604 	for (i = 0; i < PCM_N_URBS; i++) {
605 		ret = hiface_pcm_init_urb(&rt->out_urbs[i], chip, OUT_EP,
606 				    hiface_pcm_out_urb_handler);
607 		if (ret < 0)
608 			return ret;
609 	}
610 
611 	ret = snd_pcm_new(chip->card, "USB-SPDIF Audio", 0, 1, 0, &pcm);
612 	if (ret < 0) {
613 		kfree(rt);
614 		dev_err(&chip->dev->dev, "Cannot create pcm instance\n");
615 		return ret;
616 	}
617 
618 	pcm->private_data = rt;
619 	pcm->private_free = hiface_pcm_free;
620 
621 	strlcpy(pcm->name, "USB-SPDIF Audio", sizeof(pcm->name));
622 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &pcm_ops);
623 
624 	rt->instance = pcm;
625 
626 	chip->pcm = rt;
627 	return 0;
628 }
629