xref: /linux/sound/usb/usx2y/usbusx2yaudio.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   US-X2Y AUDIO
4  *   Copyright (c) 2002-2004 by Karsten Wiese
5  *
6  *   based on
7  *
8  *   (Tentative) USB Audio Driver for ALSA
9  *
10  *   Main and PCM part
11  *
12  *   Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
13  *
14  *   Many codes borrowed from audio.c by
15  *	    Alan Cox (alan@lxorguk.ukuu.org.uk)
16  *	    Thomas Sailer (sailer@ife.ee.ethz.ch)
17  */
18 
19 
20 #include <linux/interrupt.h>
21 #include <linux/slab.h>
22 #include <linux/usb.h>
23 #include <linux/moduleparam.h>
24 #include <sound/core.h>
25 #include <sound/info.h>
26 #include <sound/pcm.h>
27 #include <sound/pcm_params.h>
28 #include "usx2y.h"
29 #include "usbusx2y.h"
30 
31 /* Default value used for nr of packs per urb.
32  * 1 to 4 have been tested ok on uhci.
33  * To use 3 on ohci, you'd need a patch:
34  * look for "0000425-linux-2.6.9-rc4-mm1_ohci-hcd.patch.gz" on
35  * "https://bugtrack.alsa-project.org/alsa-bug/bug_view_page.php?bug_id=0000425"
36  *
37  * 1, 2 and 4 work out of the box on ohci, if I recall correctly.
38  * Bigger is safer operation, smaller gives lower latencies.
39  */
40 #define USX2Y_NRPACKS 4
41 
42 /* If your system works ok with this module's parameter
43  * nrpacks set to 1, you might as well comment
44  * this define out, and thereby produce smaller, faster code.
45  * You'd also set USX2Y_NRPACKS to 1 then.
46  */
47 #define USX2Y_NRPACKS_VARIABLE 1
48 
49 #ifdef USX2Y_NRPACKS_VARIABLE
50 static int nrpacks = USX2Y_NRPACKS; /* number of packets per urb */
51 #define  nr_of_packs() nrpacks
52 module_param(nrpacks, int, 0444);
53 MODULE_PARM_DESC(nrpacks, "Number of packets per URB.");
54 #else
55 #define nr_of_packs() USX2Y_NRPACKS
56 #endif
57 
58 static int usx2y_urb_capt_retire(struct snd_usx2y_substream *subs)
59 {
60 	struct urb	*urb = subs->completed_urb;
61 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
62 	unsigned char	*cp;
63 	int		i, len, lens = 0, hwptr_done = subs->hwptr_done;
64 	int		cnt, blen;
65 	struct usx2ydev	*usx2y = subs->usx2y;
66 
67 	for (i = 0; i < nr_of_packs(); i++) {
68 		cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
69 		if (urb->iso_frame_desc[i].status) { /* active? hmm, skip this */
70 			dev_err(&usx2y->dev->dev,
71 				"%s: active frame status %i. Most probably some hardware problem.\n",
72 				__func__,
73 				urb->iso_frame_desc[i].status);
74 			return urb->iso_frame_desc[i].status;
75 		}
76 		len = urb->iso_frame_desc[i].actual_length / usx2y->stride;
77 		if (!len) {
78 			dev_dbg(&usx2y->dev->dev, "%s: 0 == len ERROR!\n", __func__);
79 			continue;
80 		}
81 
82 		/* copy a data chunk */
83 		if ((hwptr_done + len) > runtime->buffer_size) {
84 			cnt = runtime->buffer_size - hwptr_done;
85 			blen = cnt * usx2y->stride;
86 			memcpy(runtime->dma_area + hwptr_done * usx2y->stride, cp, blen);
87 			memcpy(runtime->dma_area, cp + blen, len * usx2y->stride - blen);
88 		} else {
89 			memcpy(runtime->dma_area + hwptr_done * usx2y->stride, cp,
90 			       len * usx2y->stride);
91 		}
92 		lens += len;
93 		hwptr_done += len;
94 		if (hwptr_done >= runtime->buffer_size)
95 			hwptr_done -= runtime->buffer_size;
96 	}
97 
98 	subs->hwptr_done = hwptr_done;
99 	subs->transfer_done += lens;
100 	/* update the pointer, call callback if necessary */
101 	if (subs->transfer_done >= runtime->period_size) {
102 		subs->transfer_done -= runtime->period_size;
103 		snd_pcm_period_elapsed(subs->pcm_substream);
104 	}
105 	return 0;
106 }
107 
108 /*
109  * prepare urb for playback data pipe
110  *
111  * we copy the data directly from the pcm buffer.
112  * the current position to be copied is held in hwptr field.
113  * since a urb can handle only a single linear buffer, if the total
114  * transferred area overflows the buffer boundary, we cannot send
115  * it directly from the buffer.  thus the data is once copied to
116  * a temporary buffer and urb points to that.
117  */
118 static int usx2y_urb_play_prepare(struct snd_usx2y_substream *subs,
119 				  struct urb *cap_urb,
120 				  struct urb *urb)
121 {
122 	struct usx2ydev *usx2y = subs->usx2y;
123 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
124 	int count, counts, pack, len;
125 
126 	count = 0;
127 	for (pack = 0; pack <  nr_of_packs(); pack++) {
128 		/* calculate the size of a packet */
129 		counts = cap_urb->iso_frame_desc[pack].actual_length / usx2y->stride;
130 		count += counts;
131 		if (counts < 43 || counts > 50) {
132 			dev_err(&usx2y->dev->dev, "%s: should not be here with counts=%i\n",
133 				__func__, counts);
134 			return -EPIPE;
135 		}
136 		/* set up descriptor */
137 		urb->iso_frame_desc[pack].offset = pack ?
138 			urb->iso_frame_desc[pack - 1].offset +
139 			urb->iso_frame_desc[pack - 1].length :
140 			0;
141 		urb->iso_frame_desc[pack].length = cap_urb->iso_frame_desc[pack].actual_length;
142 	}
143 	if (atomic_read(&subs->state) >= STATE_PRERUNNING) {
144 		if (subs->hwptr + count > runtime->buffer_size) {
145 			/* err, the transferred area goes over buffer boundary.
146 			 * copy the data to the temp buffer.
147 			 */
148 			len = runtime->buffer_size - subs->hwptr;
149 			urb->transfer_buffer = subs->tmpbuf;
150 			memcpy(subs->tmpbuf, runtime->dma_area +
151 			       subs->hwptr * usx2y->stride, len * usx2y->stride);
152 			memcpy(subs->tmpbuf + len * usx2y->stride,
153 			       runtime->dma_area, (count - len) * usx2y->stride);
154 			subs->hwptr += count;
155 			subs->hwptr -= runtime->buffer_size;
156 		} else {
157 			/* set the buffer pointer */
158 			urb->transfer_buffer = runtime->dma_area + subs->hwptr * usx2y->stride;
159 			subs->hwptr += count;
160 			if (subs->hwptr >= runtime->buffer_size)
161 				subs->hwptr -= runtime->buffer_size;
162 		}
163 	} else {
164 		urb->transfer_buffer = subs->tmpbuf;
165 	}
166 	urb->transfer_buffer_length = count * usx2y->stride;
167 	return 0;
168 }
169 
170 /*
171  * process after playback data complete
172  *
173  * update the current position and call callback if a period is processed.
174  */
175 static void usx2y_urb_play_retire(struct snd_usx2y_substream *subs, struct urb *urb)
176 {
177 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
178 	int		len = urb->actual_length / subs->usx2y->stride;
179 
180 	subs->transfer_done += len;
181 	subs->hwptr_done +=  len;
182 	if (subs->hwptr_done >= runtime->buffer_size)
183 		subs->hwptr_done -= runtime->buffer_size;
184 	if (subs->transfer_done >= runtime->period_size) {
185 		subs->transfer_done -= runtime->period_size;
186 		snd_pcm_period_elapsed(subs->pcm_substream);
187 	}
188 }
189 
190 static int usx2y_urb_submit(struct snd_usx2y_substream *subs, struct urb *urb, int frame)
191 {
192 	int err;
193 
194 	if (!urb)
195 		return -ENODEV;
196 	urb->start_frame = frame + NRURBS * nr_of_packs();  // let hcd do rollover sanity checks
197 	urb->hcpriv = NULL;
198 	urb->dev = subs->usx2y->dev; /* we need to set this at each time */
199 	err = usb_submit_urb(urb, GFP_ATOMIC);
200 	if (err < 0) {
201 		dev_err(&urb->dev->dev, "%s: usb_submit_urb() returned %i\n",
202 			__func__, err);
203 		return err;
204 	}
205 	return 0;
206 }
207 
208 static int usx2y_usbframe_complete(struct snd_usx2y_substream *capsubs,
209 				   struct snd_usx2y_substream *playbacksubs,
210 				   int frame)
211 {
212 	int err, state;
213 	struct urb *urb = playbacksubs->completed_urb;
214 
215 	state = atomic_read(&playbacksubs->state);
216 	if (urb) {
217 		if (state == STATE_RUNNING)
218 			usx2y_urb_play_retire(playbacksubs, urb);
219 		else if (state >= STATE_PRERUNNING)
220 			atomic_inc(&playbacksubs->state);
221 	} else {
222 		switch (state) {
223 		case STATE_STARTING1:
224 			urb = playbacksubs->urb[0];
225 			atomic_inc(&playbacksubs->state);
226 			break;
227 		case STATE_STARTING2:
228 			urb = playbacksubs->urb[1];
229 			atomic_inc(&playbacksubs->state);
230 			break;
231 		}
232 	}
233 	if (urb) {
234 		err = usx2y_urb_play_prepare(playbacksubs, capsubs->completed_urb, urb);
235 		if (err)
236 			return err;
237 		err = usx2y_urb_submit(playbacksubs, urb, frame);
238 		if (err)
239 			return err;
240 	}
241 
242 	playbacksubs->completed_urb = NULL;
243 
244 	state = atomic_read(&capsubs->state);
245 	if (state >= STATE_PREPARED) {
246 		if (state == STATE_RUNNING) {
247 			err = usx2y_urb_capt_retire(capsubs);
248 			if (err)
249 				return err;
250 		} else if (state >= STATE_PRERUNNING) {
251 			atomic_inc(&capsubs->state);
252 		}
253 		err = usx2y_urb_submit(capsubs, capsubs->completed_urb, frame);
254 		if (err)
255 			return err;
256 	}
257 	capsubs->completed_urb = NULL;
258 	return 0;
259 }
260 
261 static void usx2y_clients_stop(struct usx2ydev *usx2y)
262 {
263 	struct snd_usx2y_substream *subs;
264 	struct urb *urb;
265 	int s, u;
266 
267 	for (s = 0; s < 4; s++) {
268 		subs = usx2y->subs[s];
269 		if (subs) {
270 			dev_dbg(&usx2y->dev->dev, "%s: %i %p state=%i\n",
271 				__func__, s, subs, atomic_read(&subs->state));
272 			atomic_set(&subs->state, STATE_STOPPED);
273 		}
274 	}
275 	for (s = 0; s < 4; s++) {
276 		subs = usx2y->subs[s];
277 		if (subs) {
278 			if (atomic_read(&subs->state) >= STATE_PRERUNNING)
279 				snd_pcm_stop_xrun(subs->pcm_substream);
280 			for (u = 0; u < NRURBS; u++) {
281 				urb = subs->urb[u];
282 				if (urb)
283 					dev_dbg(&usx2y->dev->dev,
284 						"%s: %i status=%i start_frame=%i\n",
285 						__func__, u, urb->status, urb->start_frame);
286 			}
287 		}
288 	}
289 	usx2y->prepare_subs = NULL;
290 	wake_up(&usx2y->prepare_wait_queue);
291 }
292 
293 static void usx2y_error_urb_status(struct usx2ydev *usx2y,
294 				   struct snd_usx2y_substream *subs, struct urb *urb)
295 {
296 	dev_err(&usx2y->dev->dev, "%s: ep=%i stalled with status=%i\n",
297 		__func__, subs->endpoint, urb->status);
298 	urb->status = 0;
299 	usx2y_clients_stop(usx2y);
300 }
301 
302 static void i_usx2y_urb_complete(struct urb *urb)
303 {
304 	struct snd_usx2y_substream *subs = urb->context;
305 	struct usx2ydev *usx2y = subs->usx2y;
306 	struct snd_usx2y_substream *capsubs, *playbacksubs;
307 
308 	if (unlikely(atomic_read(&subs->state) < STATE_PREPARED)) {
309 		dev_dbg(&usx2y->dev->dev,
310 			"%s: hcd_frame=%i ep=%i%s status=%i start_frame=%i\n",
311 			__func__,
312 			usb_get_current_frame_number(usx2y->dev),
313 			subs->endpoint, usb_pipein(urb->pipe) ? "in" : "out",
314 			urb->status, urb->start_frame);
315 		return;
316 	}
317 	if (unlikely(urb->status)) {
318 		usx2y_error_urb_status(usx2y, subs, urb);
319 		return;
320 	}
321 
322 	subs->completed_urb = urb;
323 
324 	capsubs = usx2y->subs[SNDRV_PCM_STREAM_CAPTURE];
325 	playbacksubs = usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK];
326 
327 	if (capsubs->completed_urb &&
328 	    atomic_read(&capsubs->state) >= STATE_PREPARED &&
329 	    (playbacksubs->completed_urb ||
330 	     atomic_read(&playbacksubs->state) < STATE_PREPARED)) {
331 		if (!usx2y_usbframe_complete(capsubs, playbacksubs, urb->start_frame)) {
332 			usx2y->wait_iso_frame += nr_of_packs();
333 		} else {
334 			usx2y_clients_stop(usx2y);
335 		}
336 	}
337 }
338 
339 static void usx2y_urbs_set_complete(struct usx2ydev *usx2y,
340 				    void (*complete)(struct urb *))
341 {
342 	struct snd_usx2y_substream *subs;
343 	struct urb *urb;
344 	int s, u;
345 
346 	for (s = 0; s < 4; s++) {
347 		subs = usx2y->subs[s];
348 		if (subs) {
349 			for (u = 0; u < NRURBS; u++) {
350 				urb = subs->urb[u];
351 				if (urb)
352 					urb->complete = complete;
353 			}
354 		}
355 	}
356 }
357 
358 static void usx2y_subs_startup_finish(struct usx2ydev *usx2y)
359 {
360 	usx2y_urbs_set_complete(usx2y, i_usx2y_urb_complete);
361 	usx2y->prepare_subs = NULL;
362 }
363 
364 static void i_usx2y_subs_startup(struct urb *urb)
365 {
366 	struct snd_usx2y_substream *subs = urb->context;
367 	struct usx2ydev *usx2y = subs->usx2y;
368 	struct snd_usx2y_substream *prepare_subs = usx2y->prepare_subs;
369 
370 	if (prepare_subs) {
371 		if (urb->start_frame == prepare_subs->urb[0]->start_frame) {
372 			usx2y_subs_startup_finish(usx2y);
373 			atomic_inc(&prepare_subs->state);
374 			wake_up(&usx2y->prepare_wait_queue);
375 		}
376 	}
377 
378 	i_usx2y_urb_complete(urb);
379 }
380 
381 static void usx2y_subs_prepare(struct snd_usx2y_substream *subs)
382 {
383 	dev_dbg(&subs->usx2y->dev->dev,
384 		"%s(%p) ep=%i urb0=%p urb1=%p\n",
385 		__func__, subs, subs->endpoint, subs->urb[0], subs->urb[1]);
386 	/* reset the pointer */
387 	subs->hwptr = 0;
388 	subs->hwptr_done = 0;
389 	subs->transfer_done = 0;
390 }
391 
392 static void usx2y_urb_release(struct urb **urb, int free_tb)
393 {
394 	if (*urb) {
395 		usb_kill_urb(*urb);
396 		if (free_tb)
397 			kfree((*urb)->transfer_buffer);
398 		usb_free_urb(*urb);
399 		*urb = NULL;
400 	}
401 }
402 
403 /*
404  * release a substreams urbs
405  */
406 static void usx2y_urbs_release(struct snd_usx2y_substream *subs)
407 {
408 	int i;
409 
410 	dev_dbg(&subs->usx2y->dev->dev, "%s %i\n", __func__, subs->endpoint);
411 	for (i = 0; i < NRURBS; i++)
412 		usx2y_urb_release(subs->urb + i,
413 				  subs != subs->usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK]);
414 
415 	kfree(subs->tmpbuf);
416 	subs->tmpbuf = NULL;
417 }
418 
419 /*
420  * initialize a substream's urbs
421  */
422 static int usx2y_urbs_allocate(struct snd_usx2y_substream *subs)
423 {
424 	int i;
425 	unsigned int pipe;
426 	int is_playback = subs == subs->usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK];
427 	struct usb_device *dev = subs->usx2y->dev;
428 	struct urb **purb;
429 
430 	pipe = is_playback ? usb_sndisocpipe(dev, subs->endpoint) :
431 			usb_rcvisocpipe(dev, subs->endpoint);
432 	subs->maxpacksize = usb_maxpacket(dev, pipe);
433 	if (!subs->maxpacksize)
434 		return -EINVAL;
435 
436 	if (is_playback && !subs->tmpbuf) {	/* allocate a temporary buffer for playback */
437 		subs->tmpbuf = kcalloc(nr_of_packs(), subs->maxpacksize, GFP_KERNEL);
438 		if (!subs->tmpbuf)
439 			return -ENOMEM;
440 	}
441 	/* allocate and initialize data urbs */
442 	for (i = 0; i < NRURBS; i++) {
443 		purb = subs->urb + i;
444 		if (*purb) {
445 			usb_kill_urb(*purb);
446 			continue;
447 		}
448 		*purb = usb_alloc_urb(nr_of_packs(), GFP_KERNEL);
449 		if (!*purb) {
450 			usx2y_urbs_release(subs);
451 			return -ENOMEM;
452 		}
453 		if (!is_playback && !(*purb)->transfer_buffer) {
454 			/* allocate a capture buffer per urb */
455 			(*purb)->transfer_buffer =
456 				kmalloc_array(subs->maxpacksize,
457 					      nr_of_packs(), GFP_KERNEL);
458 			if (!(*purb)->transfer_buffer) {
459 				usx2y_urbs_release(subs);
460 				return -ENOMEM;
461 			}
462 		}
463 		(*purb)->dev = dev;
464 		(*purb)->pipe = pipe;
465 		(*purb)->number_of_packets = nr_of_packs();
466 		(*purb)->context = subs;
467 		(*purb)->interval = 1;
468 		(*purb)->complete = i_usx2y_subs_startup;
469 	}
470 	return 0;
471 }
472 
473 static void usx2y_subs_startup(struct snd_usx2y_substream *subs)
474 {
475 	struct usx2ydev *usx2y = subs->usx2y;
476 
477 	usx2y->prepare_subs = subs;
478 	subs->urb[0]->start_frame = -1;
479 	wmb();
480 	usx2y_urbs_set_complete(usx2y, i_usx2y_subs_startup);
481 }
482 
483 static int usx2y_urbs_start(struct snd_usx2y_substream *subs)
484 {
485 	int i, err;
486 	struct usx2ydev *usx2y = subs->usx2y;
487 	struct urb *urb;
488 	unsigned long pack;
489 
490 	err = usx2y_urbs_allocate(subs);
491 	if (err < 0)
492 		return err;
493 	subs->completed_urb = NULL;
494 	for (i = 0; i < 4; i++) {
495 		struct snd_usx2y_substream *subs = usx2y->subs[i];
496 
497 		if (subs && atomic_read(&subs->state) >= STATE_PREPARED)
498 			goto start;
499 	}
500 
501  start:
502 	usx2y_subs_startup(subs);
503 	for (i = 0; i < NRURBS; i++) {
504 		urb = subs->urb[i];
505 		if (usb_pipein(urb->pipe)) {
506 			if (!i)
507 				atomic_set(&subs->state, STATE_STARTING3);
508 			urb->dev = usx2y->dev;
509 			for (pack = 0; pack < nr_of_packs(); pack++) {
510 				urb->iso_frame_desc[pack].offset = subs->maxpacksize * pack;
511 				urb->iso_frame_desc[pack].length = subs->maxpacksize;
512 			}
513 			urb->transfer_buffer_length = subs->maxpacksize * nr_of_packs();
514 			err = usb_submit_urb(urb, GFP_ATOMIC);
515 			if (err < 0) {
516 				dev_err(&urb->dev->dev, "%s: cannot submit datapipe for urb %d, err = %d\n",
517 					__func__, i, err);
518 				err = -EPIPE;
519 				goto cleanup;
520 			} else {
521 				if (!i)
522 					usx2y->wait_iso_frame = urb->start_frame;
523 			}
524 			urb->transfer_flags = 0;
525 		} else {
526 			atomic_set(&subs->state, STATE_STARTING1);
527 			break;
528 		}
529 	}
530 	err = 0;
531 	wait_event(usx2y->prepare_wait_queue, !usx2y->prepare_subs);
532 	if (atomic_read(&subs->state) != STATE_PREPARED)
533 		err = -EPIPE;
534 
535  cleanup:
536 	if (err) {
537 		usx2y_subs_startup_finish(usx2y);
538 		usx2y_clients_stop(usx2y);	// something is completely wrong > stop everything
539 	}
540 	return err;
541 }
542 
543 /*
544  * return the current pcm pointer.  just return the hwptr_done value.
545  */
546 static snd_pcm_uframes_t snd_usx2y_pcm_pointer(struct snd_pcm_substream *substream)
547 {
548 	struct snd_usx2y_substream *subs = substream->runtime->private_data;
549 
550 	return subs->hwptr_done;
551 }
552 
553 /*
554  * start/stop substream
555  */
556 static int snd_usx2y_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
557 {
558 	struct snd_usx2y_substream *subs = substream->runtime->private_data;
559 
560 	switch (cmd) {
561 	case SNDRV_PCM_TRIGGER_START:
562 		dev_dbg(&subs->usx2y->dev->dev, "%s(START)\n", __func__);
563 		if (atomic_read(&subs->state) == STATE_PREPARED &&
564 		    atomic_read(&subs->usx2y->subs[SNDRV_PCM_STREAM_CAPTURE]->state) >= STATE_PREPARED) {
565 			atomic_set(&subs->state, STATE_PRERUNNING);
566 		} else {
567 			return -EPIPE;
568 		}
569 		break;
570 	case SNDRV_PCM_TRIGGER_STOP:
571 		dev_dbg(&subs->usx2y->dev->dev, "%s(STOP)\n", __func__);
572 		if (atomic_read(&subs->state) >= STATE_PRERUNNING)
573 			atomic_set(&subs->state, STATE_PREPARED);
574 		break;
575 	default:
576 		return -EINVAL;
577 	}
578 	return 0;
579 }
580 
581 /*
582  * allocate a buffer, setup samplerate
583  *
584  * so far we use a physically linear buffer although packetize transfer
585  * doesn't need a continuous area.
586  * if sg buffer is supported on the later version of alsa, we'll follow
587  * that.
588  */
589 struct s_c2 {
590 	char c1, c2;
591 };
592 
593 static const struct s_c2 setrate_44100[] = {
594 	{ 0x14, 0x08},	// this line sets 44100, well actually a little less
595 	{ 0x18, 0x40},	// only tascam / frontier design knows the further lines .......
596 	{ 0x18, 0x42},
597 	{ 0x18, 0x45},
598 	{ 0x18, 0x46},
599 	{ 0x18, 0x48},
600 	{ 0x18, 0x4A},
601 	{ 0x18, 0x4C},
602 	{ 0x18, 0x4E},
603 	{ 0x18, 0x50},
604 	{ 0x18, 0x52},
605 	{ 0x18, 0x54},
606 	{ 0x18, 0x56},
607 	{ 0x18, 0x58},
608 	{ 0x18, 0x5A},
609 	{ 0x18, 0x5C},
610 	{ 0x18, 0x5E},
611 	{ 0x18, 0x60},
612 	{ 0x18, 0x62},
613 	{ 0x18, 0x64},
614 	{ 0x18, 0x66},
615 	{ 0x18, 0x68},
616 	{ 0x18, 0x6A},
617 	{ 0x18, 0x6C},
618 	{ 0x18, 0x6E},
619 	{ 0x18, 0x70},
620 	{ 0x18, 0x72},
621 	{ 0x18, 0x74},
622 	{ 0x18, 0x76},
623 	{ 0x18, 0x78},
624 	{ 0x18, 0x7A},
625 	{ 0x18, 0x7C},
626 	{ 0x18, 0x7E}
627 };
628 
629 static const struct s_c2 setrate_48000[] = {
630 	{ 0x14, 0x09},	// this line sets 48000, well actually a little less
631 	{ 0x18, 0x40},	// only tascam / frontier design knows the further lines .......
632 	{ 0x18, 0x42},
633 	{ 0x18, 0x45},
634 	{ 0x18, 0x46},
635 	{ 0x18, 0x48},
636 	{ 0x18, 0x4A},
637 	{ 0x18, 0x4C},
638 	{ 0x18, 0x4E},
639 	{ 0x18, 0x50},
640 	{ 0x18, 0x52},
641 	{ 0x18, 0x54},
642 	{ 0x18, 0x56},
643 	{ 0x18, 0x58},
644 	{ 0x18, 0x5A},
645 	{ 0x18, 0x5C},
646 	{ 0x18, 0x5E},
647 	{ 0x18, 0x60},
648 	{ 0x18, 0x62},
649 	{ 0x18, 0x64},
650 	{ 0x18, 0x66},
651 	{ 0x18, 0x68},
652 	{ 0x18, 0x6A},
653 	{ 0x18, 0x6C},
654 	{ 0x18, 0x6E},
655 	{ 0x18, 0x70},
656 	{ 0x18, 0x73},
657 	{ 0x18, 0x74},
658 	{ 0x18, 0x76},
659 	{ 0x18, 0x78},
660 	{ 0x18, 0x7A},
661 	{ 0x18, 0x7C},
662 	{ 0x18, 0x7E}
663 };
664 
665 #define NOOF_SETRATE_URBS ARRAY_SIZE(setrate_48000)
666 
667 static void i_usx2y_04int(struct urb *urb)
668 {
669 	struct usx2ydev *usx2y = urb->context;
670 
671 	if (urb->status)
672 		dev_err(&urb->dev->dev, "%s() urb->status=%i\n",
673 			__func__, urb->status);
674 	if (!--usx2y->us04->len)
675 		wake_up(&usx2y->in04_wait_queue);
676 }
677 
678 static int usx2y_rate_set(struct usx2ydev *usx2y, int rate)
679 {
680 	int err = 0, i;
681 	struct snd_usx2y_urb_seq *us = NULL;
682 	int *usbdata = NULL;
683 	const struct s_c2 *ra = rate == 48000 ? setrate_48000 : setrate_44100;
684 	struct urb *urb;
685 
686 	if (usx2y->rate != rate) {
687 		us = kzalloc(struct_size(us, urb, NOOF_SETRATE_URBS),
688 			     GFP_KERNEL);
689 		if (!us) {
690 			err = -ENOMEM;
691 			goto cleanup;
692 		}
693 		us->len = NOOF_SETRATE_URBS;
694 		usbdata = kmalloc_array(NOOF_SETRATE_URBS, sizeof(int),
695 					GFP_KERNEL);
696 		if (!usbdata) {
697 			err = -ENOMEM;
698 			goto cleanup;
699 		}
700 		for (i = 0; i < NOOF_SETRATE_URBS; ++i) {
701 			us->urb[i] = usb_alloc_urb(0, GFP_KERNEL);
702 			if (!us->urb[i]) {
703 				err = -ENOMEM;
704 				goto cleanup;
705 			}
706 			((char *)(usbdata + i))[0] = ra[i].c1;
707 			((char *)(usbdata + i))[1] = ra[i].c2;
708 			usb_fill_bulk_urb(us->urb[i], usx2y->dev, usb_sndbulkpipe(usx2y->dev, 4),
709 					  usbdata + i, 2, i_usx2y_04int, usx2y);
710 		}
711 		err = usb_urb_ep_type_check(us->urb[0]);
712 		if (err < 0)
713 			goto cleanup;
714 		us->submitted =	0;
715 		usx2y->us04 =	us;
716 		wait_event_timeout(usx2y->in04_wait_queue, !us->len, HZ);
717 		usx2y->us04 =	NULL;
718 		if (us->len)
719 			err = -ENODEV;
720 	cleanup:
721 		if (us) {
722 			us->submitted =	2*NOOF_SETRATE_URBS;
723 			for (i = 0; i < NOOF_SETRATE_URBS; ++i) {
724 				urb = us->urb[i];
725 				if (!urb)
726 					continue;
727 				if (urb->status) {
728 					if (!err)
729 						err = -ENODEV;
730 					usb_kill_urb(urb);
731 				}
732 				usb_free_urb(urb);
733 			}
734 			usx2y->us04 = NULL;
735 			kfree(usbdata);
736 			kfree(us);
737 			if (!err)
738 				usx2y->rate = rate;
739 		}
740 	}
741 
742 	return err;
743 }
744 
745 static int usx2y_format_set(struct usx2ydev *usx2y, snd_pcm_format_t format)
746 {
747 	int alternate, err;
748 	struct list_head *p;
749 
750 	if (format == SNDRV_PCM_FORMAT_S24_3LE) {
751 		alternate = 2;
752 		usx2y->stride = 6;
753 	} else {
754 		alternate = 1;
755 		usx2y->stride = 4;
756 	}
757 	list_for_each(p, &usx2y->midi_list) {
758 		snd_usbmidi_input_stop(p);
759 	}
760 	usb_kill_urb(usx2y->in04_urb);
761 	err = usb_set_interface(usx2y->dev, 0, alternate);
762 	if (err) {
763 		dev_err(&usx2y->dev->dev, "%s: usb_set_interface error\n",
764 			__func__);
765 		return err;
766 	}
767 	usx2y->in04_urb->dev = usx2y->dev;
768 	err = usb_submit_urb(usx2y->in04_urb, GFP_KERNEL);
769 	list_for_each(p, &usx2y->midi_list) {
770 		snd_usbmidi_input_start(p);
771 	}
772 	usx2y->format = format;
773 	usx2y->rate = 0;
774 	return err;
775 }
776 
777 
778 static int snd_usx2y_pcm_hw_params(struct snd_pcm_substream *substream,
779 				   struct snd_pcm_hw_params *hw_params)
780 {
781 	int			err = 0;
782 	unsigned int		rate = params_rate(hw_params);
783 	snd_pcm_format_t	format = params_format(hw_params);
784 	struct snd_card *card = substream->pstr->pcm->card;
785 	struct usx2ydev	*dev = usx2y(card);
786 	struct snd_usx2y_substream *subs;
787 	struct snd_pcm_substream *test_substream;
788 	int i;
789 
790 	mutex_lock(&usx2y(card)->pcm_mutex);
791 	dev_dbg(&dev->dev->dev, "%s(%p, %p)\n", __func__, substream, hw_params);
792 	/* all pcm substreams off one usx2y have to operate at the same
793 	 * rate & format
794 	 */
795 	for (i = 0; i < dev->pcm_devs * 2; i++) {
796 		subs = dev->subs[i];
797 		if (!subs)
798 			continue;
799 		test_substream = subs->pcm_substream;
800 		if (!test_substream || test_substream == substream ||
801 		    !test_substream->runtime)
802 			continue;
803 		if ((test_substream->runtime->format &&
804 		     test_substream->runtime->format != format) ||
805 		    (test_substream->runtime->rate &&
806 		     test_substream->runtime->rate != rate)) {
807 			err = -EINVAL;
808 			goto error;
809 		}
810 	}
811 
812  error:
813 	mutex_unlock(&usx2y(card)->pcm_mutex);
814 	return err;
815 }
816 
817 /*
818  * free the buffer
819  */
820 static int snd_usx2y_pcm_hw_free(struct snd_pcm_substream *substream)
821 {
822 	struct snd_pcm_runtime *runtime = substream->runtime;
823 	struct snd_usx2y_substream *subs = runtime->private_data;
824 	struct snd_usx2y_substream *cap_subs, *playback_subs;
825 
826 	mutex_lock(&subs->usx2y->pcm_mutex);
827 	dev_dbg(&subs->usx2y->dev->dev, "%s(%p)\n", __func__, substream);
828 
829 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
830 		cap_subs = subs->usx2y->subs[SNDRV_PCM_STREAM_CAPTURE];
831 		atomic_set(&subs->state, STATE_STOPPED);
832 		usx2y_urbs_release(subs);
833 		if (!cap_subs->pcm_substream ||
834 		    !cap_subs->pcm_substream->runtime ||
835 		    cap_subs->pcm_substream->runtime->state < SNDRV_PCM_STATE_PREPARED) {
836 			atomic_set(&cap_subs->state, STATE_STOPPED);
837 			usx2y_urbs_release(cap_subs);
838 		}
839 	} else {
840 		playback_subs = subs->usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK];
841 		if (atomic_read(&playback_subs->state) < STATE_PREPARED) {
842 			atomic_set(&subs->state, STATE_STOPPED);
843 			usx2y_urbs_release(subs);
844 		}
845 	}
846 	mutex_unlock(&subs->usx2y->pcm_mutex);
847 	return 0;
848 }
849 
850 /*
851  * prepare callback
852  *
853  * set format and initialize urbs
854  */
855 static int snd_usx2y_pcm_prepare(struct snd_pcm_substream *substream)
856 {
857 	struct snd_pcm_runtime *runtime = substream->runtime;
858 	struct snd_usx2y_substream *subs = runtime->private_data;
859 	struct usx2ydev *usx2y = subs->usx2y;
860 	struct snd_usx2y_substream *capsubs = subs->usx2y->subs[SNDRV_PCM_STREAM_CAPTURE];
861 	int err = 0;
862 
863 	dev_dbg(&usx2y->dev->dev, "%s(%p)\n", __func__, substream);
864 
865 	mutex_lock(&usx2y->pcm_mutex);
866 	usx2y_subs_prepare(subs);
867 	// Start hardware streams
868 	// SyncStream first....
869 	if (atomic_read(&capsubs->state) < STATE_PREPARED) {
870 		if (usx2y->format != runtime->format) {
871 			err = usx2y_format_set(usx2y, runtime->format);
872 			if (err < 0)
873 				goto up_prepare_mutex;
874 		}
875 		if (usx2y->rate != runtime->rate) {
876 			err = usx2y_rate_set(usx2y, runtime->rate);
877 			if (err < 0)
878 				goto up_prepare_mutex;
879 		}
880 		dev_dbg(&usx2y->dev->dev, "%s: starting capture pipe for %s\n",
881 			__func__, subs == capsubs ? "self" : "playpipe");
882 		err = usx2y_urbs_start(capsubs);
883 		if (err < 0)
884 			goto up_prepare_mutex;
885 	}
886 
887 	if (subs != capsubs && atomic_read(&subs->state) < STATE_PREPARED)
888 		err = usx2y_urbs_start(subs);
889 
890  up_prepare_mutex:
891 	mutex_unlock(&usx2y->pcm_mutex);
892 	return err;
893 }
894 
895 static const struct snd_pcm_hardware snd_usx2y_2c = {
896 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
897 				 SNDRV_PCM_INFO_BLOCK_TRANSFER |
898 				 SNDRV_PCM_INFO_MMAP_VALID |
899 				 SNDRV_PCM_INFO_BATCH),
900 	.formats =                 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_3LE,
901 	.rates =                   SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000,
902 	.rate_min =                44100,
903 	.rate_max =                48000,
904 	.channels_min =            2,
905 	.channels_max =            2,
906 	.buffer_bytes_max =	(2*128*1024),
907 	.period_bytes_min =	64,
908 	.period_bytes_max =	(128*1024),
909 	.periods_min =		2,
910 	.periods_max =		1024,
911 	.fifo_size =              0
912 };
913 
914 static int snd_usx2y_pcm_open(struct snd_pcm_substream *substream)
915 {
916 	struct snd_usx2y_substream	*subs =
917 		((struct snd_usx2y_substream **)
918 		 snd_pcm_substream_chip(substream))[substream->stream];
919 	struct snd_pcm_runtime	*runtime = substream->runtime;
920 
921 	if (subs->usx2y->chip_status & USX2Y_STAT_CHIP_MMAP_PCM_URBS)
922 		return -EBUSY;
923 
924 	runtime->hw = snd_usx2y_2c;
925 	runtime->private_data = subs;
926 	subs->pcm_substream = substream;
927 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME, 1000, 200000);
928 	return 0;
929 }
930 
931 static int snd_usx2y_pcm_close(struct snd_pcm_substream *substream)
932 {
933 	struct snd_pcm_runtime *runtime = substream->runtime;
934 	struct snd_usx2y_substream *subs = runtime->private_data;
935 
936 	subs->pcm_substream = NULL;
937 
938 	return 0;
939 }
940 
941 static const struct snd_pcm_ops snd_usx2y_pcm_ops = {
942 	.open =		snd_usx2y_pcm_open,
943 	.close =	snd_usx2y_pcm_close,
944 	.hw_params =	snd_usx2y_pcm_hw_params,
945 	.hw_free =	snd_usx2y_pcm_hw_free,
946 	.prepare =	snd_usx2y_pcm_prepare,
947 	.trigger =	snd_usx2y_pcm_trigger,
948 	.pointer =	snd_usx2y_pcm_pointer,
949 };
950 
951 /*
952  * free a usb stream instance
953  */
954 static void usx2y_audio_stream_free(struct snd_usx2y_substream **usx2y_substream)
955 {
956 	int stream;
957 
958 	for_each_pcm_streams(stream) {
959 		kfree(usx2y_substream[stream]);
960 		usx2y_substream[stream] = NULL;
961 	}
962 }
963 
964 static void snd_usx2y_pcm_private_free(struct snd_pcm *pcm)
965 {
966 	struct snd_usx2y_substream **usx2y_stream = pcm->private_data;
967 
968 	if (usx2y_stream)
969 		usx2y_audio_stream_free(usx2y_stream);
970 }
971 
972 static int usx2y_audio_stream_new(struct snd_card *card, int playback_endpoint, int capture_endpoint)
973 {
974 	struct snd_pcm *pcm;
975 	int err, i;
976 	struct snd_usx2y_substream **usx2y_substream =
977 		usx2y(card)->subs + 2 * usx2y(card)->pcm_devs;
978 
979 	for (i = playback_endpoint ? SNDRV_PCM_STREAM_PLAYBACK : SNDRV_PCM_STREAM_CAPTURE;
980 	     i <= SNDRV_PCM_STREAM_CAPTURE; ++i) {
981 		usx2y_substream[i] = kzalloc(sizeof(struct snd_usx2y_substream), GFP_KERNEL);
982 		if (!usx2y_substream[i])
983 			return -ENOMEM;
984 
985 		usx2y_substream[i]->usx2y = usx2y(card);
986 	}
987 
988 	if (playback_endpoint)
989 		usx2y_substream[SNDRV_PCM_STREAM_PLAYBACK]->endpoint = playback_endpoint;
990 	usx2y_substream[SNDRV_PCM_STREAM_CAPTURE]->endpoint = capture_endpoint;
991 
992 	err = snd_pcm_new(card, NAME_ALLCAPS" Audio", usx2y(card)->pcm_devs,
993 			  playback_endpoint ? 1 : 0, 1,
994 			  &pcm);
995 	if (err < 0) {
996 		usx2y_audio_stream_free(usx2y_substream);
997 		return err;
998 	}
999 
1000 	if (playback_endpoint)
1001 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_usx2y_pcm_ops);
1002 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_usx2y_pcm_ops);
1003 
1004 	pcm->private_data = usx2y_substream;
1005 	pcm->private_free = snd_usx2y_pcm_private_free;
1006 	pcm->info_flags = 0;
1007 
1008 	sprintf(pcm->name, NAME_ALLCAPS" Audio #%d", usx2y(card)->pcm_devs);
1009 
1010 	if (playback_endpoint) {
1011 		snd_pcm_set_managed_buffer(pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream,
1012 					   SNDRV_DMA_TYPE_CONTINUOUS,
1013 					   NULL,
1014 					   64*1024, 128*1024);
1015 	}
1016 
1017 	snd_pcm_set_managed_buffer(pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream,
1018 				   SNDRV_DMA_TYPE_CONTINUOUS,
1019 				   NULL,
1020 				   64*1024, 128*1024);
1021 	usx2y(card)->pcm_devs++;
1022 
1023 	return 0;
1024 }
1025 
1026 /*
1027  * create a chip instance and set its names.
1028  */
1029 int usx2y_audio_create(struct snd_card *card)
1030 {
1031 	int err;
1032 
1033 	err = usx2y_audio_stream_new(card, 0xA, 0x8);
1034 	if (err < 0)
1035 		return err;
1036 	if (le16_to_cpu(usx2y(card)->dev->descriptor.idProduct) == USB_ID_US428) {
1037 		err = usx2y_audio_stream_new(card, 0, 0xA);
1038 		if (err < 0)
1039 			return err;
1040 	}
1041 	if (le16_to_cpu(usx2y(card)->dev->descriptor.idProduct) != USB_ID_US122)
1042 		err = usx2y_rate_set(usx2y(card), 44100);	// Lets us428 recognize output-volume settings, disturbs us122.
1043 	return err;
1044 }
1045