1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux driver for M2Tech hiFace compatible devices
4 *
5 * Copyright 2012-2013 (C) M2TECH S.r.l and Amarula Solutions B.V.
6 *
7 * Authors: Michael Trimarchi <michael@amarulasolutions.com>
8 * Antonio Ospite <ao2@amarulasolutions.com>
9 *
10 * The driver is based on the work done in TerraTec DMX 6Fire USB
11 */
12
13 #include <linux/slab.h>
14 #include <sound/pcm.h>
15
16 #include "pcm.h"
17 #include "chip.h"
18
19 #define OUT_EP 0x2
20 #define PCM_N_URBS 8
21 #define PCM_PACKET_SIZE 4096
22 #define PCM_BUFFER_SIZE (2 * PCM_N_URBS * PCM_PACKET_SIZE)
23
24 struct pcm_urb {
25 struct hiface_chip *chip;
26
27 struct urb instance;
28 struct usb_anchor submitted;
29 u8 *buffer;
30 };
31
32 struct pcm_substream {
33 spinlock_t lock;
34 struct snd_pcm_substream *instance;
35
36 bool active;
37 snd_pcm_uframes_t dma_off; /* current position in alsa dma_area */
38 snd_pcm_uframes_t period_off; /* current position in current period */
39 };
40
41 enum { /* pcm streaming states */
42 STREAM_DISABLED, /* no pcm streaming */
43 STREAM_STARTING, /* pcm streaming requested, waiting to become ready */
44 STREAM_RUNNING, /* pcm streaming running */
45 STREAM_STOPPING
46 };
47
48 struct pcm_runtime {
49 struct hiface_chip *chip;
50 struct snd_pcm *instance;
51
52 struct pcm_substream playback;
53 bool panic; /* if set driver won't do anymore pcm on device */
54
55 struct pcm_urb out_urbs[PCM_N_URBS];
56
57 struct mutex stream_mutex;
58 u8 stream_state; /* one of STREAM_XXX */
59 u8 extra_freq;
60 wait_queue_head_t stream_wait_queue;
61 bool stream_wait_cond;
62 };
63
64 static const unsigned int rates[] = { 44100, 48000, 88200, 96000, 176400, 192000,
65 352800, 384000 };
66 static const struct snd_pcm_hw_constraint_list constraints_extra_rates = {
67 .count = ARRAY_SIZE(rates),
68 .list = rates,
69 .mask = 0,
70 };
71
72 static const struct snd_pcm_hardware pcm_hw = {
73 .info = SNDRV_PCM_INFO_MMAP |
74 SNDRV_PCM_INFO_INTERLEAVED |
75 SNDRV_PCM_INFO_BLOCK_TRANSFER |
76 SNDRV_PCM_INFO_PAUSE |
77 SNDRV_PCM_INFO_MMAP_VALID |
78 SNDRV_PCM_INFO_BATCH,
79
80 .formats = SNDRV_PCM_FMTBIT_S32_LE,
81
82 .rates = SNDRV_PCM_RATE_44100 |
83 SNDRV_PCM_RATE_48000 |
84 SNDRV_PCM_RATE_88200 |
85 SNDRV_PCM_RATE_96000 |
86 SNDRV_PCM_RATE_176400 |
87 SNDRV_PCM_RATE_192000,
88
89 .rate_min = 44100,
90 .rate_max = 192000, /* changes in hiface_pcm_open to support extra rates */
91 .channels_min = 2,
92 .channels_max = 2,
93 .buffer_bytes_max = PCM_BUFFER_SIZE,
94 .period_bytes_min = PCM_PACKET_SIZE,
95 .period_bytes_max = PCM_BUFFER_SIZE,
96 .periods_min = 2,
97 .periods_max = 1024
98 };
99
100 /* message values used to change the sample rate */
101 #define HIFACE_SET_RATE_REQUEST 0xb0
102
103 #define HIFACE_RATE_44100 0x43
104 #define HIFACE_RATE_48000 0x4b
105 #define HIFACE_RATE_88200 0x42
106 #define HIFACE_RATE_96000 0x4a
107 #define HIFACE_RATE_176400 0x40
108 #define HIFACE_RATE_192000 0x48
109 #define HIFACE_RATE_352800 0x58
110 #define HIFACE_RATE_384000 0x68
111
hiface_pcm_set_rate(struct pcm_runtime * rt,unsigned int rate)112 static int hiface_pcm_set_rate(struct pcm_runtime *rt, unsigned int rate)
113 {
114 struct usb_device *device = rt->chip->dev;
115 u16 rate_value;
116 int ret;
117
118 /* We are already sure that the rate is supported here thanks to
119 * ALSA constraints
120 */
121 switch (rate) {
122 case 44100:
123 rate_value = HIFACE_RATE_44100;
124 break;
125 case 48000:
126 rate_value = HIFACE_RATE_48000;
127 break;
128 case 88200:
129 rate_value = HIFACE_RATE_88200;
130 break;
131 case 96000:
132 rate_value = HIFACE_RATE_96000;
133 break;
134 case 176400:
135 rate_value = HIFACE_RATE_176400;
136 break;
137 case 192000:
138 rate_value = HIFACE_RATE_192000;
139 break;
140 case 352800:
141 rate_value = HIFACE_RATE_352800;
142 break;
143 case 384000:
144 rate_value = HIFACE_RATE_384000;
145 break;
146 default:
147 dev_err(&device->dev, "Unsupported rate %d\n", rate);
148 return -EINVAL;
149 }
150
151 /*
152 * USBIO: Vendor 0xb0(wValue=0x0043, wIndex=0x0000)
153 * 43 b0 43 00 00 00 00 00
154 * USBIO: Vendor 0xb0(wValue=0x004b, wIndex=0x0000)
155 * 43 b0 4b 00 00 00 00 00
156 * This control message doesn't have any ack from the
157 * other side
158 */
159 ret = usb_control_msg_send(device, 0,
160 HIFACE_SET_RATE_REQUEST,
161 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER,
162 rate_value, 0, NULL, 0, 100, GFP_KERNEL);
163 if (ret)
164 dev_err(&device->dev, "Error setting samplerate %d.\n", rate);
165
166 return ret;
167 }
168
hiface_pcm_get_substream(struct snd_pcm_substream * alsa_sub)169 static struct pcm_substream *hiface_pcm_get_substream(struct snd_pcm_substream
170 *alsa_sub)
171 {
172 struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
173 struct device *device = &rt->chip->dev->dev;
174
175 if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
176 return &rt->playback;
177
178 dev_err(device, "Error getting pcm substream slot.\n");
179 return NULL;
180 }
181
182 /* call with stream_mutex locked */
hiface_pcm_stream_stop(struct pcm_runtime * rt)183 static void hiface_pcm_stream_stop(struct pcm_runtime *rt)
184 {
185 int i, time;
186
187 if (rt->stream_state != STREAM_DISABLED) {
188 rt->stream_state = STREAM_STOPPING;
189
190 for (i = 0; i < PCM_N_URBS; i++) {
191 time = usb_wait_anchor_empty_timeout(
192 &rt->out_urbs[i].submitted, 100);
193 if (!time)
194 usb_kill_anchored_urbs(
195 &rt->out_urbs[i].submitted);
196 usb_kill_urb(&rt->out_urbs[i].instance);
197 }
198
199 rt->stream_state = STREAM_DISABLED;
200 }
201 }
202
203 /* call with stream_mutex locked */
hiface_pcm_stream_start(struct pcm_runtime * rt)204 static int hiface_pcm_stream_start(struct pcm_runtime *rt)
205 {
206 int ret = 0;
207 int i;
208
209 if (rt->stream_state == STREAM_DISABLED) {
210
211 /* reset panic state when starting a new stream */
212 rt->panic = false;
213
214 /* submit our out urbs zero init */
215 rt->stream_state = STREAM_STARTING;
216 for (i = 0; i < PCM_N_URBS; i++) {
217 memset(rt->out_urbs[i].buffer, 0, PCM_PACKET_SIZE);
218 usb_anchor_urb(&rt->out_urbs[i].instance,
219 &rt->out_urbs[i].submitted);
220 ret = usb_submit_urb(&rt->out_urbs[i].instance,
221 GFP_ATOMIC);
222 if (ret) {
223 hiface_pcm_stream_stop(rt);
224 return ret;
225 }
226 }
227
228 /* wait for first out urb to return (sent in urb handler) */
229 wait_event_timeout(rt->stream_wait_queue, rt->stream_wait_cond,
230 HZ);
231 if (rt->stream_wait_cond) {
232 struct device *device = &rt->chip->dev->dev;
233 dev_dbg(device, "%s: Stream is running wakeup event\n",
234 __func__);
235 rt->stream_state = STREAM_RUNNING;
236 } else {
237 hiface_pcm_stream_stop(rt);
238 return -EIO;
239 }
240 }
241 return ret;
242 }
243
244 /* The hardware wants word-swapped 32-bit values */
memcpy_swahw32(u8 * dest,u8 * src,unsigned int n)245 static void memcpy_swahw32(u8 *dest, u8 *src, unsigned int n)
246 {
247 unsigned int i;
248
249 for (i = 0; i < n / 4; i++)
250 ((u32 *)dest)[i] = swahw32(((u32 *)src)[i]);
251 }
252
253 /* call with substream locked */
254 /* returns true if a period elapsed */
hiface_pcm_playback(struct pcm_substream * sub,struct pcm_urb * urb)255 static bool hiface_pcm_playback(struct pcm_substream *sub, struct pcm_urb *urb)
256 {
257 struct snd_pcm_runtime *alsa_rt = sub->instance->runtime;
258 struct device *device = &urb->chip->dev->dev;
259 u8 *source;
260 unsigned int pcm_buffer_size;
261
262 WARN_ON(alsa_rt->format != SNDRV_PCM_FORMAT_S32_LE);
263
264 pcm_buffer_size = snd_pcm_lib_buffer_bytes(sub->instance);
265
266 if (sub->dma_off + PCM_PACKET_SIZE <= pcm_buffer_size) {
267 dev_dbg(device, "%s: (1) buffer_size %#x dma_offset %#x\n", __func__,
268 (unsigned int) pcm_buffer_size,
269 (unsigned int) sub->dma_off);
270
271 source = alsa_rt->dma_area + sub->dma_off;
272 memcpy_swahw32(urb->buffer, source, PCM_PACKET_SIZE);
273 } else {
274 /* wrap around at end of ring buffer */
275 unsigned int len;
276
277 dev_dbg(device, "%s: (2) buffer_size %#x dma_offset %#x\n", __func__,
278 (unsigned int) pcm_buffer_size,
279 (unsigned int) sub->dma_off);
280
281 len = pcm_buffer_size - sub->dma_off;
282
283 source = alsa_rt->dma_area + sub->dma_off;
284 memcpy_swahw32(urb->buffer, source, len);
285
286 source = alsa_rt->dma_area;
287 memcpy_swahw32(urb->buffer + len, source,
288 PCM_PACKET_SIZE - len);
289 }
290 sub->dma_off += PCM_PACKET_SIZE;
291 if (sub->dma_off >= pcm_buffer_size)
292 sub->dma_off -= pcm_buffer_size;
293
294 sub->period_off += PCM_PACKET_SIZE;
295 if (sub->period_off >= alsa_rt->period_size) {
296 sub->period_off %= alsa_rt->period_size;
297 return true;
298 }
299 return false;
300 }
301
hiface_pcm_out_urb_handler(struct urb * usb_urb)302 static void hiface_pcm_out_urb_handler(struct urb *usb_urb)
303 {
304 struct pcm_urb *out_urb = usb_urb->context;
305 struct pcm_runtime *rt = out_urb->chip->pcm;
306 struct pcm_substream *sub;
307 bool do_period_elapsed = false;
308 int ret;
309
310 if (rt->panic || rt->stream_state == STREAM_STOPPING)
311 return;
312
313 if (unlikely(usb_urb->status == -ENOENT || /* unlinked */
314 usb_urb->status == -ENODEV || /* device removed */
315 usb_urb->status == -ECONNRESET || /* unlinked */
316 usb_urb->status == -ESHUTDOWN)) { /* device disabled */
317 goto out_fail;
318 }
319
320 if (rt->stream_state == STREAM_STARTING) {
321 rt->stream_wait_cond = true;
322 wake_up(&rt->stream_wait_queue);
323 }
324
325 /* now send our playback data (if a free out urb was found) */
326 sub = &rt->playback;
327 scoped_guard(spinlock_irqsave, &sub->lock) {
328 if (sub->active)
329 do_period_elapsed = hiface_pcm_playback(sub, out_urb);
330 else
331 memset(out_urb->buffer, 0, PCM_PACKET_SIZE);
332 }
333
334 if (do_period_elapsed)
335 snd_pcm_period_elapsed(sub->instance);
336
337 ret = usb_submit_urb(&out_urb->instance, GFP_ATOMIC);
338 if (ret < 0)
339 goto out_fail;
340
341 return;
342
343 out_fail:
344 rt->panic = true;
345 }
346
hiface_pcm_open(struct snd_pcm_substream * alsa_sub)347 static int hiface_pcm_open(struct snd_pcm_substream *alsa_sub)
348 {
349 struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
350 struct pcm_substream *sub = NULL;
351 struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
352 int ret;
353
354 if (rt->panic)
355 return -EPIPE;
356
357 guard(mutex)(&rt->stream_mutex);
358 alsa_rt->hw = pcm_hw;
359
360 if (alsa_sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
361 sub = &rt->playback;
362
363 if (!sub) {
364 struct device *device = &rt->chip->dev->dev;
365 dev_err(device, "Invalid stream type\n");
366 return -EINVAL;
367 }
368
369 if (rt->extra_freq) {
370 alsa_rt->hw.rates |= SNDRV_PCM_RATE_KNOT;
371 alsa_rt->hw.rate_max = 384000;
372
373 /* explicit constraints needed as we added SNDRV_PCM_RATE_KNOT */
374 ret = snd_pcm_hw_constraint_list(alsa_sub->runtime, 0,
375 SNDRV_PCM_HW_PARAM_RATE,
376 &constraints_extra_rates);
377 if (ret < 0)
378 return ret;
379 }
380
381 sub->instance = alsa_sub;
382 sub->active = false;
383 return 0;
384 }
385
hiface_pcm_close(struct snd_pcm_substream * alsa_sub)386 static int hiface_pcm_close(struct snd_pcm_substream *alsa_sub)
387 {
388 struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
389 struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
390
391 if (rt->panic)
392 return 0;
393
394 guard(mutex)(&rt->stream_mutex);
395 if (sub) {
396 hiface_pcm_stream_stop(rt);
397
398 /* deactivate substream */
399 guard(spinlock_irqsave)(&sub->lock);
400 sub->instance = NULL;
401 sub->active = false;
402 }
403 return 0;
404 }
405
hiface_pcm_prepare(struct snd_pcm_substream * alsa_sub)406 static int hiface_pcm_prepare(struct snd_pcm_substream *alsa_sub)
407 {
408 struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
409 struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
410 struct snd_pcm_runtime *alsa_rt = alsa_sub->runtime;
411 int ret;
412
413 if (rt->panic)
414 return -EPIPE;
415 if (!sub)
416 return -ENODEV;
417
418 guard(mutex)(&rt->stream_mutex);
419
420 hiface_pcm_stream_stop(rt);
421
422 sub->dma_off = 0;
423 sub->period_off = 0;
424
425 if (rt->stream_state == STREAM_DISABLED) {
426
427 ret = hiface_pcm_set_rate(rt, alsa_rt->rate);
428 if (ret)
429 return ret;
430 ret = hiface_pcm_stream_start(rt);
431 if (ret)
432 return ret;
433 }
434 return 0;
435 }
436
hiface_pcm_trigger(struct snd_pcm_substream * alsa_sub,int cmd)437 static int hiface_pcm_trigger(struct snd_pcm_substream *alsa_sub, int cmd)
438 {
439 struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
440 struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
441
442 if (rt->panic)
443 return -EPIPE;
444 if (!sub)
445 return -ENODEV;
446
447 switch (cmd) {
448 case SNDRV_PCM_TRIGGER_START:
449 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
450 scoped_guard(spinlock_irq, &sub->lock) {
451 sub->active = true;
452 }
453 return 0;
454
455 case SNDRV_PCM_TRIGGER_STOP:
456 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
457 scoped_guard(spinlock_irq, &sub->lock) {
458 sub->active = false;
459 }
460 return 0;
461
462 default:
463 return -EINVAL;
464 }
465 }
466
hiface_pcm_pointer(struct snd_pcm_substream * alsa_sub)467 static snd_pcm_uframes_t hiface_pcm_pointer(struct snd_pcm_substream *alsa_sub)
468 {
469 struct pcm_substream *sub = hiface_pcm_get_substream(alsa_sub);
470 struct pcm_runtime *rt = snd_pcm_substream_chip(alsa_sub);
471 snd_pcm_uframes_t dma_offset;
472
473 if (rt->panic || !sub)
474 return SNDRV_PCM_POS_XRUN;
475
476 guard(spinlock_irqsave)(&sub->lock);
477 dma_offset = sub->dma_off;
478 return bytes_to_frames(alsa_sub->runtime, dma_offset);
479 }
480
481 static const struct snd_pcm_ops pcm_ops = {
482 .open = hiface_pcm_open,
483 .close = hiface_pcm_close,
484 .prepare = hiface_pcm_prepare,
485 .trigger = hiface_pcm_trigger,
486 .pointer = hiface_pcm_pointer,
487 };
488
hiface_pcm_init_urb(struct pcm_urb * urb,struct hiface_chip * chip,unsigned int ep,void (* handler)(struct urb *))489 static int hiface_pcm_init_urb(struct pcm_urb *urb,
490 struct hiface_chip *chip,
491 unsigned int ep,
492 void (*handler)(struct urb *))
493 {
494 urb->chip = chip;
495 usb_init_urb(&urb->instance);
496
497 urb->buffer = kzalloc(PCM_PACKET_SIZE, GFP_KERNEL);
498 if (!urb->buffer)
499 return -ENOMEM;
500
501 usb_fill_bulk_urb(&urb->instance, chip->dev,
502 usb_sndbulkpipe(chip->dev, ep), (void *)urb->buffer,
503 PCM_PACKET_SIZE, handler, urb);
504 if (usb_urb_ep_type_check(&urb->instance))
505 return -EINVAL;
506 init_usb_anchor(&urb->submitted);
507
508 return 0;
509 }
510
hiface_pcm_abort(struct hiface_chip * chip)511 void hiface_pcm_abort(struct hiface_chip *chip)
512 {
513 struct pcm_runtime *rt = chip->pcm;
514
515 if (rt) {
516 rt->panic = true;
517
518 guard(mutex)(&rt->stream_mutex);
519 hiface_pcm_stream_stop(rt);
520 }
521 }
522
hiface_pcm_destroy(struct hiface_chip * chip)523 static void hiface_pcm_destroy(struct hiface_chip *chip)
524 {
525 struct pcm_runtime *rt = chip->pcm;
526 int i;
527
528 for (i = 0; i < PCM_N_URBS; i++)
529 kfree(rt->out_urbs[i].buffer);
530
531 kfree(chip->pcm);
532 chip->pcm = NULL;
533 }
534
hiface_pcm_free(struct snd_pcm * pcm)535 static void hiface_pcm_free(struct snd_pcm *pcm)
536 {
537 struct pcm_runtime *rt = pcm->private_data;
538
539 if (rt)
540 hiface_pcm_destroy(rt->chip);
541 }
542
hiface_pcm_init(struct hiface_chip * chip,u8 extra_freq)543 int hiface_pcm_init(struct hiface_chip *chip, u8 extra_freq)
544 {
545 int i;
546 int ret;
547 struct snd_pcm *pcm;
548 struct pcm_runtime *rt;
549
550 rt = kzalloc_obj(*rt);
551 if (!rt)
552 return -ENOMEM;
553
554 rt->chip = chip;
555 rt->stream_state = STREAM_DISABLED;
556 if (extra_freq)
557 rt->extra_freq = 1;
558
559 init_waitqueue_head(&rt->stream_wait_queue);
560 mutex_init(&rt->stream_mutex);
561 spin_lock_init(&rt->playback.lock);
562
563 for (i = 0; i < PCM_N_URBS; i++) {
564 ret = hiface_pcm_init_urb(&rt->out_urbs[i], chip, OUT_EP,
565 hiface_pcm_out_urb_handler);
566 if (ret < 0)
567 goto error;
568 }
569
570 ret = snd_pcm_new(chip->card, "USB-SPDIF Audio", 0, 1, 0, &pcm);
571 if (ret < 0) {
572 dev_err(&chip->dev->dev, "Cannot create pcm instance\n");
573 goto error;
574 }
575
576 pcm->private_data = rt;
577 pcm->private_free = hiface_pcm_free;
578
579 strscpy(pcm->name, "USB-SPDIF Audio", sizeof(pcm->name));
580 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &pcm_ops);
581 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC,
582 NULL, 0, 0);
583
584 rt->instance = pcm;
585
586 chip->pcm = rt;
587 return 0;
588
589 error:
590 for (i = 0; i < PCM_N_URBS; i++)
591 kfree(rt->out_urbs[i].buffer);
592 kfree(rt);
593 return ret;
594 }
595