xref: /linux/sound/usb/usx2y/usbusx2yaudio.c (revision d99ff463ecf651437e9e4abe68f331dfb6b5bd9d)
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 			snd_printk(KERN_ERR
71 				   "active frame status %i. Most probably some hardware problem.\n",
72 				   urb->iso_frame_desc[i].status);
73 			return urb->iso_frame_desc[i].status;
74 		}
75 		len = urb->iso_frame_desc[i].actual_length / usx2y->stride;
76 		if (!len) {
77 			snd_printd("0 == len ERROR!\n");
78 			continue;
79 		}
80 
81 		/* copy a data chunk */
82 		if ((hwptr_done + len) > runtime->buffer_size) {
83 			cnt = runtime->buffer_size - hwptr_done;
84 			blen = cnt * usx2y->stride;
85 			memcpy(runtime->dma_area + hwptr_done * usx2y->stride, cp, blen);
86 			memcpy(runtime->dma_area, cp + blen, len * usx2y->stride - blen);
87 		} else {
88 			memcpy(runtime->dma_area + hwptr_done * usx2y->stride, cp,
89 			       len * usx2y->stride);
90 		}
91 		lens += len;
92 		hwptr_done += len;
93 		if (hwptr_done >= runtime->buffer_size)
94 			hwptr_done -= runtime->buffer_size;
95 	}
96 
97 	subs->hwptr_done = hwptr_done;
98 	subs->transfer_done += lens;
99 	/* update the pointer, call callback if necessary */
100 	if (subs->transfer_done >= runtime->period_size) {
101 		subs->transfer_done -= runtime->period_size;
102 		snd_pcm_period_elapsed(subs->pcm_substream);
103 	}
104 	return 0;
105 }
106 
107 /*
108  * prepare urb for playback data pipe
109  *
110  * we copy the data directly from the pcm buffer.
111  * the current position to be copied is held in hwptr field.
112  * since a urb can handle only a single linear buffer, if the total
113  * transferred area overflows the buffer boundary, we cannot send
114  * it directly from the buffer.  thus the data is once copied to
115  * a temporary buffer and urb points to that.
116  */
117 static int usx2y_urb_play_prepare(struct snd_usx2y_substream *subs,
118 				  struct urb *cap_urb,
119 				  struct urb *urb)
120 {
121 	struct usx2ydev *usx2y = subs->usx2y;
122 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
123 	int count, counts, pack, len;
124 
125 	count = 0;
126 	for (pack = 0; pack <  nr_of_packs(); pack++) {
127 		/* calculate the size of a packet */
128 		counts = cap_urb->iso_frame_desc[pack].actual_length / usx2y->stride;
129 		count += counts;
130 		if (counts < 43 || counts > 50) {
131 			snd_printk(KERN_ERR "should not be here with counts=%i\n", counts);
132 			return -EPIPE;
133 		}
134 		/* set up descriptor */
135 		urb->iso_frame_desc[pack].offset = pack ?
136 			urb->iso_frame_desc[pack - 1].offset +
137 			urb->iso_frame_desc[pack - 1].length :
138 			0;
139 		urb->iso_frame_desc[pack].length = cap_urb->iso_frame_desc[pack].actual_length;
140 	}
141 	if (atomic_read(&subs->state) >= STATE_PRERUNNING) {
142 		if (subs->hwptr + count > runtime->buffer_size) {
143 			/* err, the transferred area goes over buffer boundary.
144 			 * copy the data to the temp buffer.
145 			 */
146 			len = runtime->buffer_size - subs->hwptr;
147 			urb->transfer_buffer = subs->tmpbuf;
148 			memcpy(subs->tmpbuf, runtime->dma_area +
149 			       subs->hwptr * usx2y->stride, len * usx2y->stride);
150 			memcpy(subs->tmpbuf + len * usx2y->stride,
151 			       runtime->dma_area, (count - len) * usx2y->stride);
152 			subs->hwptr += count;
153 			subs->hwptr -= runtime->buffer_size;
154 		} else {
155 			/* set the buffer pointer */
156 			urb->transfer_buffer = runtime->dma_area + subs->hwptr * usx2y->stride;
157 			subs->hwptr += count;
158 			if (subs->hwptr >= runtime->buffer_size)
159 				subs->hwptr -= runtime->buffer_size;
160 		}
161 	} else {
162 		urb->transfer_buffer = subs->tmpbuf;
163 	}
164 	urb->transfer_buffer_length = count * usx2y->stride;
165 	return 0;
166 }
167 
168 /*
169  * process after playback data complete
170  *
171  * update the current position and call callback if a period is processed.
172  */
173 static void usx2y_urb_play_retire(struct snd_usx2y_substream *subs, struct urb *urb)
174 {
175 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
176 	int		len = urb->actual_length / subs->usx2y->stride;
177 
178 	subs->transfer_done += len;
179 	subs->hwptr_done +=  len;
180 	if (subs->hwptr_done >= runtime->buffer_size)
181 		subs->hwptr_done -= runtime->buffer_size;
182 	if (subs->transfer_done >= runtime->period_size) {
183 		subs->transfer_done -= runtime->period_size;
184 		snd_pcm_period_elapsed(subs->pcm_substream);
185 	}
186 }
187 
188 static int usx2y_urb_submit(struct snd_usx2y_substream *subs, struct urb *urb, int frame)
189 {
190 	int err;
191 
192 	if (!urb)
193 		return -ENODEV;
194 	urb->start_frame = frame + NRURBS * nr_of_packs();  // let hcd do rollover sanity checks
195 	urb->hcpriv = NULL;
196 	urb->dev = subs->usx2y->dev; /* we need to set this at each time */
197 	err = usb_submit_urb(urb, GFP_ATOMIC);
198 	if (err < 0) {
199 		snd_printk(KERN_ERR "usb_submit_urb() returned %i\n", err);
200 		return err;
201 	}
202 	return 0;
203 }
204 
205 static int usx2y_usbframe_complete(struct snd_usx2y_substream *capsubs,
206 				   struct snd_usx2y_substream *playbacksubs,
207 				   int frame)
208 {
209 	int err, state;
210 	struct urb *urb = playbacksubs->completed_urb;
211 
212 	state = atomic_read(&playbacksubs->state);
213 	if (urb) {
214 		if (state == STATE_RUNNING)
215 			usx2y_urb_play_retire(playbacksubs, urb);
216 		else if (state >= STATE_PRERUNNING)
217 			atomic_inc(&playbacksubs->state);
218 	} else {
219 		switch (state) {
220 		case STATE_STARTING1:
221 			urb = playbacksubs->urb[0];
222 			atomic_inc(&playbacksubs->state);
223 			break;
224 		case STATE_STARTING2:
225 			urb = playbacksubs->urb[1];
226 			atomic_inc(&playbacksubs->state);
227 			break;
228 		}
229 	}
230 	if (urb) {
231 		err = usx2y_urb_play_prepare(playbacksubs, capsubs->completed_urb, urb);
232 		if (err)
233 			return err;
234 		err = usx2y_urb_submit(playbacksubs, urb, frame);
235 		if (err)
236 			return err;
237 	}
238 
239 	playbacksubs->completed_urb = NULL;
240 
241 	state = atomic_read(&capsubs->state);
242 	if (state >= STATE_PREPARED) {
243 		if (state == STATE_RUNNING) {
244 			err = usx2y_urb_capt_retire(capsubs);
245 			if (err)
246 				return err;
247 		} else if (state >= STATE_PRERUNNING) {
248 			atomic_inc(&capsubs->state);
249 		}
250 		err = usx2y_urb_submit(capsubs, capsubs->completed_urb, frame);
251 		if (err)
252 			return err;
253 	}
254 	capsubs->completed_urb = NULL;
255 	return 0;
256 }
257 
258 static void usx2y_clients_stop(struct usx2ydev *usx2y)
259 {
260 	struct snd_usx2y_substream *subs;
261 	struct urb *urb;
262 	int s, u;
263 
264 	for (s = 0; s < 4; s++) {
265 		subs = usx2y->subs[s];
266 		if (subs) {
267 			snd_printdd("%i %p state=%i\n", s, subs, atomic_read(&subs->state));
268 			atomic_set(&subs->state, STATE_STOPPED);
269 		}
270 	}
271 	for (s = 0; s < 4; s++) {
272 		subs = usx2y->subs[s];
273 		if (subs) {
274 			if (atomic_read(&subs->state) >= STATE_PRERUNNING)
275 				snd_pcm_stop_xrun(subs->pcm_substream);
276 			for (u = 0; u < NRURBS; u++) {
277 				urb = subs->urb[u];
278 				if (urb)
279 					snd_printdd("%i status=%i start_frame=%i\n",
280 						    u, urb->status, urb->start_frame);
281 			}
282 		}
283 	}
284 	usx2y->prepare_subs = NULL;
285 	wake_up(&usx2y->prepare_wait_queue);
286 }
287 
288 static void usx2y_error_urb_status(struct usx2ydev *usx2y,
289 				   struct snd_usx2y_substream *subs, struct urb *urb)
290 {
291 	snd_printk(KERN_ERR "ep=%i stalled with status=%i\n", subs->endpoint, urb->status);
292 	urb->status = 0;
293 	usx2y_clients_stop(usx2y);
294 }
295 
296 static void i_usx2y_urb_complete(struct urb *urb)
297 {
298 	struct snd_usx2y_substream *subs = urb->context;
299 	struct usx2ydev *usx2y = subs->usx2y;
300 	struct snd_usx2y_substream *capsubs, *playbacksubs;
301 
302 	if (unlikely(atomic_read(&subs->state) < STATE_PREPARED)) {
303 		snd_printdd("hcd_frame=%i ep=%i%s status=%i start_frame=%i\n",
304 			    usb_get_current_frame_number(usx2y->dev),
305 			    subs->endpoint, usb_pipein(urb->pipe) ? "in" : "out",
306 			    urb->status, urb->start_frame);
307 		return;
308 	}
309 	if (unlikely(urb->status)) {
310 		usx2y_error_urb_status(usx2y, subs, urb);
311 		return;
312 	}
313 
314 	subs->completed_urb = urb;
315 
316 	capsubs = usx2y->subs[SNDRV_PCM_STREAM_CAPTURE];
317 	playbacksubs = usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK];
318 
319 	if (capsubs->completed_urb &&
320 	    atomic_read(&capsubs->state) >= STATE_PREPARED &&
321 	    (playbacksubs->completed_urb ||
322 	     atomic_read(&playbacksubs->state) < STATE_PREPARED)) {
323 		if (!usx2y_usbframe_complete(capsubs, playbacksubs, urb->start_frame)) {
324 			usx2y->wait_iso_frame += nr_of_packs();
325 		} else {
326 			snd_printdd("\n");
327 			usx2y_clients_stop(usx2y);
328 		}
329 	}
330 }
331 
332 static void usx2y_urbs_set_complete(struct usx2ydev *usx2y,
333 				    void (*complete)(struct urb *))
334 {
335 	struct snd_usx2y_substream *subs;
336 	struct urb *urb;
337 	int s, u;
338 
339 	for (s = 0; s < 4; s++) {
340 		subs = usx2y->subs[s];
341 		if (subs) {
342 			for (u = 0; u < NRURBS; u++) {
343 				urb = subs->urb[u];
344 				if (urb)
345 					urb->complete = complete;
346 			}
347 		}
348 	}
349 }
350 
351 static void usx2y_subs_startup_finish(struct usx2ydev *usx2y)
352 {
353 	usx2y_urbs_set_complete(usx2y, i_usx2y_urb_complete);
354 	usx2y->prepare_subs = NULL;
355 }
356 
357 static void i_usx2y_subs_startup(struct urb *urb)
358 {
359 	struct snd_usx2y_substream *subs = urb->context;
360 	struct usx2ydev *usx2y = subs->usx2y;
361 	struct snd_usx2y_substream *prepare_subs = usx2y->prepare_subs;
362 
363 	if (prepare_subs) {
364 		if (urb->start_frame == prepare_subs->urb[0]->start_frame) {
365 			usx2y_subs_startup_finish(usx2y);
366 			atomic_inc(&prepare_subs->state);
367 			wake_up(&usx2y->prepare_wait_queue);
368 		}
369 	}
370 
371 	i_usx2y_urb_complete(urb);
372 }
373 
374 static void usx2y_subs_prepare(struct snd_usx2y_substream *subs)
375 {
376 	snd_printdd("usx2y_substream_prepare(%p) ep=%i urb0=%p urb1=%p\n",
377 		    subs, subs->endpoint, subs->urb[0], subs->urb[1]);
378 	/* reset the pointer */
379 	subs->hwptr = 0;
380 	subs->hwptr_done = 0;
381 	subs->transfer_done = 0;
382 }
383 
384 static void usx2y_urb_release(struct urb **urb, int free_tb)
385 {
386 	if (*urb) {
387 		usb_kill_urb(*urb);
388 		if (free_tb)
389 			kfree((*urb)->transfer_buffer);
390 		usb_free_urb(*urb);
391 		*urb = NULL;
392 	}
393 }
394 
395 /*
396  * release a substreams urbs
397  */
398 static void usx2y_urbs_release(struct snd_usx2y_substream *subs)
399 {
400 	int i;
401 
402 	snd_printdd("%s %i\n", __func__, subs->endpoint);
403 	for (i = 0; i < NRURBS; i++)
404 		usx2y_urb_release(subs->urb + i,
405 				  subs != subs->usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK]);
406 
407 	kfree(subs->tmpbuf);
408 	subs->tmpbuf = NULL;
409 }
410 
411 /*
412  * initialize a substream's urbs
413  */
414 static int usx2y_urbs_allocate(struct snd_usx2y_substream *subs)
415 {
416 	int i;
417 	unsigned int pipe;
418 	int is_playback = subs == subs->usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK];
419 	struct usb_device *dev = subs->usx2y->dev;
420 	struct urb **purb;
421 
422 	pipe = is_playback ? usb_sndisocpipe(dev, subs->endpoint) :
423 			usb_rcvisocpipe(dev, subs->endpoint);
424 	subs->maxpacksize = usb_maxpacket(dev, pipe);
425 	if (!subs->maxpacksize)
426 		return -EINVAL;
427 
428 	if (is_playback && !subs->tmpbuf) {	/* allocate a temporary buffer for playback */
429 		subs->tmpbuf = kcalloc(nr_of_packs(), subs->maxpacksize, GFP_KERNEL);
430 		if (!subs->tmpbuf)
431 			return -ENOMEM;
432 	}
433 	/* allocate and initialize data urbs */
434 	for (i = 0; i < NRURBS; i++) {
435 		purb = subs->urb + i;
436 		if (*purb) {
437 			usb_kill_urb(*purb);
438 			continue;
439 		}
440 		*purb = usb_alloc_urb(nr_of_packs(), GFP_KERNEL);
441 		if (!*purb) {
442 			usx2y_urbs_release(subs);
443 			return -ENOMEM;
444 		}
445 		if (!is_playback && !(*purb)->transfer_buffer) {
446 			/* allocate a capture buffer per urb */
447 			(*purb)->transfer_buffer =
448 				kmalloc_array(subs->maxpacksize,
449 					      nr_of_packs(), GFP_KERNEL);
450 			if (!(*purb)->transfer_buffer) {
451 				usx2y_urbs_release(subs);
452 				return -ENOMEM;
453 			}
454 		}
455 		(*purb)->dev = dev;
456 		(*purb)->pipe = pipe;
457 		(*purb)->number_of_packets = nr_of_packs();
458 		(*purb)->context = subs;
459 		(*purb)->interval = 1;
460 		(*purb)->complete = i_usx2y_subs_startup;
461 	}
462 	return 0;
463 }
464 
465 static void usx2y_subs_startup(struct snd_usx2y_substream *subs)
466 {
467 	struct usx2ydev *usx2y = subs->usx2y;
468 
469 	usx2y->prepare_subs = subs;
470 	subs->urb[0]->start_frame = -1;
471 	wmb();
472 	usx2y_urbs_set_complete(usx2y, i_usx2y_subs_startup);
473 }
474 
475 static int usx2y_urbs_start(struct snd_usx2y_substream *subs)
476 {
477 	int i, err;
478 	struct usx2ydev *usx2y = subs->usx2y;
479 	struct urb *urb;
480 	unsigned long pack;
481 
482 	err = usx2y_urbs_allocate(subs);
483 	if (err < 0)
484 		return err;
485 	subs->completed_urb = NULL;
486 	for (i = 0; i < 4; i++) {
487 		struct snd_usx2y_substream *subs = usx2y->subs[i];
488 
489 		if (subs && atomic_read(&subs->state) >= STATE_PREPARED)
490 			goto start;
491 	}
492 
493  start:
494 	usx2y_subs_startup(subs);
495 	for (i = 0; i < NRURBS; i++) {
496 		urb = subs->urb[i];
497 		if (usb_pipein(urb->pipe)) {
498 			if (!i)
499 				atomic_set(&subs->state, STATE_STARTING3);
500 			urb->dev = usx2y->dev;
501 			for (pack = 0; pack < nr_of_packs(); pack++) {
502 				urb->iso_frame_desc[pack].offset = subs->maxpacksize * pack;
503 				urb->iso_frame_desc[pack].length = subs->maxpacksize;
504 			}
505 			urb->transfer_buffer_length = subs->maxpacksize * nr_of_packs();
506 			err = usb_submit_urb(urb, GFP_ATOMIC);
507 			if (err < 0) {
508 				snd_printk(KERN_ERR "cannot submit datapipe for urb %d, err = %d\n", i, err);
509 				err = -EPIPE;
510 				goto cleanup;
511 			} else {
512 				if (!i)
513 					usx2y->wait_iso_frame = urb->start_frame;
514 			}
515 			urb->transfer_flags = 0;
516 		} else {
517 			atomic_set(&subs->state, STATE_STARTING1);
518 			break;
519 		}
520 	}
521 	err = 0;
522 	wait_event(usx2y->prepare_wait_queue, !usx2y->prepare_subs);
523 	if (atomic_read(&subs->state) != STATE_PREPARED)
524 		err = -EPIPE;
525 
526  cleanup:
527 	if (err) {
528 		usx2y_subs_startup_finish(usx2y);
529 		usx2y_clients_stop(usx2y);	// something is completely wrong > stop everything
530 	}
531 	return err;
532 }
533 
534 /*
535  * return the current pcm pointer.  just return the hwptr_done value.
536  */
537 static snd_pcm_uframes_t snd_usx2y_pcm_pointer(struct snd_pcm_substream *substream)
538 {
539 	struct snd_usx2y_substream *subs = substream->runtime->private_data;
540 
541 	return subs->hwptr_done;
542 }
543 
544 /*
545  * start/stop substream
546  */
547 static int snd_usx2y_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
548 {
549 	struct snd_usx2y_substream *subs = substream->runtime->private_data;
550 
551 	switch (cmd) {
552 	case SNDRV_PCM_TRIGGER_START:
553 		snd_printdd("%s(START)\n", __func__);
554 		if (atomic_read(&subs->state) == STATE_PREPARED &&
555 		    atomic_read(&subs->usx2y->subs[SNDRV_PCM_STREAM_CAPTURE]->state) >= STATE_PREPARED) {
556 			atomic_set(&subs->state, STATE_PRERUNNING);
557 		} else {
558 			snd_printdd("\n");
559 			return -EPIPE;
560 		}
561 		break;
562 	case SNDRV_PCM_TRIGGER_STOP:
563 		snd_printdd("%s(STOP)\n", __func__);
564 		if (atomic_read(&subs->state) >= STATE_PRERUNNING)
565 			atomic_set(&subs->state, STATE_PREPARED);
566 		break;
567 	default:
568 		return -EINVAL;
569 	}
570 	return 0;
571 }
572 
573 /*
574  * allocate a buffer, setup samplerate
575  *
576  * so far we use a physically linear buffer although packetize transfer
577  * doesn't need a continuous area.
578  * if sg buffer is supported on the later version of alsa, we'll follow
579  * that.
580  */
581 struct s_c2 {
582 	char c1, c2;
583 };
584 
585 static const struct s_c2 setrate_44100[] = {
586 	{ 0x14, 0x08},	// this line sets 44100, well actually a little less
587 	{ 0x18, 0x40},	// only tascam / frontier design knows the further lines .......
588 	{ 0x18, 0x42},
589 	{ 0x18, 0x45},
590 	{ 0x18, 0x46},
591 	{ 0x18, 0x48},
592 	{ 0x18, 0x4A},
593 	{ 0x18, 0x4C},
594 	{ 0x18, 0x4E},
595 	{ 0x18, 0x50},
596 	{ 0x18, 0x52},
597 	{ 0x18, 0x54},
598 	{ 0x18, 0x56},
599 	{ 0x18, 0x58},
600 	{ 0x18, 0x5A},
601 	{ 0x18, 0x5C},
602 	{ 0x18, 0x5E},
603 	{ 0x18, 0x60},
604 	{ 0x18, 0x62},
605 	{ 0x18, 0x64},
606 	{ 0x18, 0x66},
607 	{ 0x18, 0x68},
608 	{ 0x18, 0x6A},
609 	{ 0x18, 0x6C},
610 	{ 0x18, 0x6E},
611 	{ 0x18, 0x70},
612 	{ 0x18, 0x72},
613 	{ 0x18, 0x74},
614 	{ 0x18, 0x76},
615 	{ 0x18, 0x78},
616 	{ 0x18, 0x7A},
617 	{ 0x18, 0x7C},
618 	{ 0x18, 0x7E}
619 };
620 
621 static const struct s_c2 setrate_48000[] = {
622 	{ 0x14, 0x09},	// this line sets 48000, well actually a little less
623 	{ 0x18, 0x40},	// only tascam / frontier design knows the further lines .......
624 	{ 0x18, 0x42},
625 	{ 0x18, 0x45},
626 	{ 0x18, 0x46},
627 	{ 0x18, 0x48},
628 	{ 0x18, 0x4A},
629 	{ 0x18, 0x4C},
630 	{ 0x18, 0x4E},
631 	{ 0x18, 0x50},
632 	{ 0x18, 0x52},
633 	{ 0x18, 0x54},
634 	{ 0x18, 0x56},
635 	{ 0x18, 0x58},
636 	{ 0x18, 0x5A},
637 	{ 0x18, 0x5C},
638 	{ 0x18, 0x5E},
639 	{ 0x18, 0x60},
640 	{ 0x18, 0x62},
641 	{ 0x18, 0x64},
642 	{ 0x18, 0x66},
643 	{ 0x18, 0x68},
644 	{ 0x18, 0x6A},
645 	{ 0x18, 0x6C},
646 	{ 0x18, 0x6E},
647 	{ 0x18, 0x70},
648 	{ 0x18, 0x73},
649 	{ 0x18, 0x74},
650 	{ 0x18, 0x76},
651 	{ 0x18, 0x78},
652 	{ 0x18, 0x7A},
653 	{ 0x18, 0x7C},
654 	{ 0x18, 0x7E}
655 };
656 
657 #define NOOF_SETRATE_URBS ARRAY_SIZE(setrate_48000)
658 
659 static void i_usx2y_04int(struct urb *urb)
660 {
661 	struct usx2ydev *usx2y = urb->context;
662 
663 	if (urb->status)
664 		snd_printk(KERN_ERR "snd_usx2y_04int() urb->status=%i\n", urb->status);
665 	if (!--usx2y->us04->len)
666 		wake_up(&usx2y->in04_wait_queue);
667 }
668 
669 static int usx2y_rate_set(struct usx2ydev *usx2y, int rate)
670 {
671 	int err = 0, i;
672 	struct snd_usx2y_urb_seq *us = NULL;
673 	int *usbdata = NULL;
674 	const struct s_c2 *ra = rate == 48000 ? setrate_48000 : setrate_44100;
675 	struct urb *urb;
676 
677 	if (usx2y->rate != rate) {
678 		us = kzalloc(struct_size(us, urb, NOOF_SETRATE_URBS),
679 			     GFP_KERNEL);
680 		if (!us) {
681 			err = -ENOMEM;
682 			goto cleanup;
683 		}
684 		usbdata = kmalloc_array(NOOF_SETRATE_URBS, sizeof(int),
685 					GFP_KERNEL);
686 		if (!usbdata) {
687 			err = -ENOMEM;
688 			goto cleanup;
689 		}
690 		for (i = 0; i < NOOF_SETRATE_URBS; ++i) {
691 			us->urb[i] = usb_alloc_urb(0, GFP_KERNEL);
692 			if (!us->urb[i]) {
693 				err = -ENOMEM;
694 				goto cleanup;
695 			}
696 			((char *)(usbdata + i))[0] = ra[i].c1;
697 			((char *)(usbdata + i))[1] = ra[i].c2;
698 			usb_fill_bulk_urb(us->urb[i], usx2y->dev, usb_sndbulkpipe(usx2y->dev, 4),
699 					  usbdata + i, 2, i_usx2y_04int, usx2y);
700 		}
701 		err = usb_urb_ep_type_check(us->urb[0]);
702 		if (err < 0)
703 			goto cleanup;
704 		us->submitted =	0;
705 		us->len =	NOOF_SETRATE_URBS;
706 		usx2y->us04 =	us;
707 		wait_event_timeout(usx2y->in04_wait_queue, !us->len, HZ);
708 		usx2y->us04 =	NULL;
709 		if (us->len)
710 			err = -ENODEV;
711 	cleanup:
712 		if (us) {
713 			us->submitted =	2*NOOF_SETRATE_URBS;
714 			for (i = 0; i < NOOF_SETRATE_URBS; ++i) {
715 				urb = us->urb[i];
716 				if (!urb)
717 					continue;
718 				if (urb->status) {
719 					if (!err)
720 						err = -ENODEV;
721 					usb_kill_urb(urb);
722 				}
723 				usb_free_urb(urb);
724 			}
725 			usx2y->us04 = NULL;
726 			kfree(usbdata);
727 			kfree(us);
728 			if (!err)
729 				usx2y->rate = rate;
730 		}
731 	}
732 
733 	return err;
734 }
735 
736 static int usx2y_format_set(struct usx2ydev *usx2y, snd_pcm_format_t format)
737 {
738 	int alternate, err;
739 	struct list_head *p;
740 
741 	if (format == SNDRV_PCM_FORMAT_S24_3LE) {
742 		alternate = 2;
743 		usx2y->stride = 6;
744 	} else {
745 		alternate = 1;
746 		usx2y->stride = 4;
747 	}
748 	list_for_each(p, &usx2y->midi_list) {
749 		snd_usbmidi_input_stop(p);
750 	}
751 	usb_kill_urb(usx2y->in04_urb);
752 	err = usb_set_interface(usx2y->dev, 0, alternate);
753 	if (err) {
754 		snd_printk(KERN_ERR "usb_set_interface error\n");
755 		return err;
756 	}
757 	usx2y->in04_urb->dev = usx2y->dev;
758 	err = usb_submit_urb(usx2y->in04_urb, GFP_KERNEL);
759 	list_for_each(p, &usx2y->midi_list) {
760 		snd_usbmidi_input_start(p);
761 	}
762 	usx2y->format = format;
763 	usx2y->rate = 0;
764 	return err;
765 }
766 
767 
768 static int snd_usx2y_pcm_hw_params(struct snd_pcm_substream *substream,
769 				   struct snd_pcm_hw_params *hw_params)
770 {
771 	int			err = 0;
772 	unsigned int		rate = params_rate(hw_params);
773 	snd_pcm_format_t	format = params_format(hw_params);
774 	struct snd_card *card = substream->pstr->pcm->card;
775 	struct usx2ydev	*dev = usx2y(card);
776 	struct snd_usx2y_substream *subs;
777 	struct snd_pcm_substream *test_substream;
778 	int i;
779 
780 	mutex_lock(&usx2y(card)->pcm_mutex);
781 	snd_printdd("snd_usx2y_hw_params(%p, %p)\n", substream, hw_params);
782 	/* all pcm substreams off one usx2y have to operate at the same
783 	 * rate & format
784 	 */
785 	for (i = 0; i < dev->pcm_devs * 2; i++) {
786 		subs = dev->subs[i];
787 		if (!subs)
788 			continue;
789 		test_substream = subs->pcm_substream;
790 		if (!test_substream || test_substream == substream ||
791 		    !test_substream->runtime)
792 			continue;
793 		if ((test_substream->runtime->format &&
794 		     test_substream->runtime->format != format) ||
795 		    (test_substream->runtime->rate &&
796 		     test_substream->runtime->rate != rate)) {
797 			err = -EINVAL;
798 			goto error;
799 		}
800 	}
801 
802  error:
803 	mutex_unlock(&usx2y(card)->pcm_mutex);
804 	return err;
805 }
806 
807 /*
808  * free the buffer
809  */
810 static int snd_usx2y_pcm_hw_free(struct snd_pcm_substream *substream)
811 {
812 	struct snd_pcm_runtime *runtime = substream->runtime;
813 	struct snd_usx2y_substream *subs = runtime->private_data;
814 	struct snd_usx2y_substream *cap_subs, *playback_subs;
815 
816 	mutex_lock(&subs->usx2y->pcm_mutex);
817 	snd_printdd("snd_usx2y_hw_free(%p)\n", substream);
818 
819 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
820 		cap_subs = subs->usx2y->subs[SNDRV_PCM_STREAM_CAPTURE];
821 		atomic_set(&subs->state, STATE_STOPPED);
822 		usx2y_urbs_release(subs);
823 		if (!cap_subs->pcm_substream ||
824 		    !cap_subs->pcm_substream->runtime ||
825 		    cap_subs->pcm_substream->runtime->state < SNDRV_PCM_STATE_PREPARED) {
826 			atomic_set(&cap_subs->state, STATE_STOPPED);
827 			usx2y_urbs_release(cap_subs);
828 		}
829 	} else {
830 		playback_subs = subs->usx2y->subs[SNDRV_PCM_STREAM_PLAYBACK];
831 		if (atomic_read(&playback_subs->state) < STATE_PREPARED) {
832 			atomic_set(&subs->state, STATE_STOPPED);
833 			usx2y_urbs_release(subs);
834 		}
835 	}
836 	mutex_unlock(&subs->usx2y->pcm_mutex);
837 	return 0;
838 }
839 
840 /*
841  * prepare callback
842  *
843  * set format and initialize urbs
844  */
845 static int snd_usx2y_pcm_prepare(struct snd_pcm_substream *substream)
846 {
847 	struct snd_pcm_runtime *runtime = substream->runtime;
848 	struct snd_usx2y_substream *subs = runtime->private_data;
849 	struct usx2ydev *usx2y = subs->usx2y;
850 	struct snd_usx2y_substream *capsubs = subs->usx2y->subs[SNDRV_PCM_STREAM_CAPTURE];
851 	int err = 0;
852 
853 	snd_printdd("%s(%p)\n", __func__, substream);
854 
855 	mutex_lock(&usx2y->pcm_mutex);
856 	usx2y_subs_prepare(subs);
857 	// Start hardware streams
858 	// SyncStream first....
859 	if (atomic_read(&capsubs->state) < STATE_PREPARED) {
860 		if (usx2y->format != runtime->format) {
861 			err = usx2y_format_set(usx2y, runtime->format);
862 			if (err < 0)
863 				goto up_prepare_mutex;
864 		}
865 		if (usx2y->rate != runtime->rate) {
866 			err = usx2y_rate_set(usx2y, runtime->rate);
867 			if (err < 0)
868 				goto up_prepare_mutex;
869 		}
870 		snd_printdd("starting capture pipe for %s\n", subs == capsubs ? "self" : "playpipe");
871 		err = usx2y_urbs_start(capsubs);
872 		if (err < 0)
873 			goto up_prepare_mutex;
874 	}
875 
876 	if (subs != capsubs && atomic_read(&subs->state) < STATE_PREPARED)
877 		err = usx2y_urbs_start(subs);
878 
879  up_prepare_mutex:
880 	mutex_unlock(&usx2y->pcm_mutex);
881 	return err;
882 }
883 
884 static const struct snd_pcm_hardware snd_usx2y_2c = {
885 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
886 				 SNDRV_PCM_INFO_BLOCK_TRANSFER |
887 				 SNDRV_PCM_INFO_MMAP_VALID |
888 				 SNDRV_PCM_INFO_BATCH),
889 	.formats =                 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_3LE,
890 	.rates =                   SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000,
891 	.rate_min =                44100,
892 	.rate_max =                48000,
893 	.channels_min =            2,
894 	.channels_max =            2,
895 	.buffer_bytes_max =	(2*128*1024),
896 	.period_bytes_min =	64,
897 	.period_bytes_max =	(128*1024),
898 	.periods_min =		2,
899 	.periods_max =		1024,
900 	.fifo_size =              0
901 };
902 
903 static int snd_usx2y_pcm_open(struct snd_pcm_substream *substream)
904 {
905 	struct snd_usx2y_substream	*subs =
906 		((struct snd_usx2y_substream **)
907 		 snd_pcm_substream_chip(substream))[substream->stream];
908 	struct snd_pcm_runtime	*runtime = substream->runtime;
909 
910 	if (subs->usx2y->chip_status & USX2Y_STAT_CHIP_MMAP_PCM_URBS)
911 		return -EBUSY;
912 
913 	runtime->hw = snd_usx2y_2c;
914 	runtime->private_data = subs;
915 	subs->pcm_substream = substream;
916 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME, 1000, 200000);
917 	return 0;
918 }
919 
920 static int snd_usx2y_pcm_close(struct snd_pcm_substream *substream)
921 {
922 	struct snd_pcm_runtime *runtime = substream->runtime;
923 	struct snd_usx2y_substream *subs = runtime->private_data;
924 
925 	subs->pcm_substream = NULL;
926 
927 	return 0;
928 }
929 
930 static const struct snd_pcm_ops snd_usx2y_pcm_ops = {
931 	.open =		snd_usx2y_pcm_open,
932 	.close =	snd_usx2y_pcm_close,
933 	.hw_params =	snd_usx2y_pcm_hw_params,
934 	.hw_free =	snd_usx2y_pcm_hw_free,
935 	.prepare =	snd_usx2y_pcm_prepare,
936 	.trigger =	snd_usx2y_pcm_trigger,
937 	.pointer =	snd_usx2y_pcm_pointer,
938 };
939 
940 /*
941  * free a usb stream instance
942  */
943 static void usx2y_audio_stream_free(struct snd_usx2y_substream **usx2y_substream)
944 {
945 	int stream;
946 
947 	for_each_pcm_streams(stream) {
948 		kfree(usx2y_substream[stream]);
949 		usx2y_substream[stream] = NULL;
950 	}
951 }
952 
953 static void snd_usx2y_pcm_private_free(struct snd_pcm *pcm)
954 {
955 	struct snd_usx2y_substream **usx2y_stream = pcm->private_data;
956 
957 	if (usx2y_stream)
958 		usx2y_audio_stream_free(usx2y_stream);
959 }
960 
961 static int usx2y_audio_stream_new(struct snd_card *card, int playback_endpoint, int capture_endpoint)
962 {
963 	struct snd_pcm *pcm;
964 	int err, i;
965 	struct snd_usx2y_substream **usx2y_substream =
966 		usx2y(card)->subs + 2 * usx2y(card)->pcm_devs;
967 
968 	for (i = playback_endpoint ? SNDRV_PCM_STREAM_PLAYBACK : SNDRV_PCM_STREAM_CAPTURE;
969 	     i <= SNDRV_PCM_STREAM_CAPTURE; ++i) {
970 		usx2y_substream[i] = kzalloc(sizeof(struct snd_usx2y_substream), GFP_KERNEL);
971 		if (!usx2y_substream[i])
972 			return -ENOMEM;
973 
974 		usx2y_substream[i]->usx2y = usx2y(card);
975 	}
976 
977 	if (playback_endpoint)
978 		usx2y_substream[SNDRV_PCM_STREAM_PLAYBACK]->endpoint = playback_endpoint;
979 	usx2y_substream[SNDRV_PCM_STREAM_CAPTURE]->endpoint = capture_endpoint;
980 
981 	err = snd_pcm_new(card, NAME_ALLCAPS" Audio", usx2y(card)->pcm_devs,
982 			  playback_endpoint ? 1 : 0, 1,
983 			  &pcm);
984 	if (err < 0) {
985 		usx2y_audio_stream_free(usx2y_substream);
986 		return err;
987 	}
988 
989 	if (playback_endpoint)
990 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_usx2y_pcm_ops);
991 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_usx2y_pcm_ops);
992 
993 	pcm->private_data = usx2y_substream;
994 	pcm->private_free = snd_usx2y_pcm_private_free;
995 	pcm->info_flags = 0;
996 
997 	sprintf(pcm->name, NAME_ALLCAPS" Audio #%d", usx2y(card)->pcm_devs);
998 
999 	if (playback_endpoint) {
1000 		snd_pcm_set_managed_buffer(pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream,
1001 					   SNDRV_DMA_TYPE_CONTINUOUS,
1002 					   NULL,
1003 					   64*1024, 128*1024);
1004 	}
1005 
1006 	snd_pcm_set_managed_buffer(pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream,
1007 				   SNDRV_DMA_TYPE_CONTINUOUS,
1008 				   NULL,
1009 				   64*1024, 128*1024);
1010 	usx2y(card)->pcm_devs++;
1011 
1012 	return 0;
1013 }
1014 
1015 /*
1016  * create a chip instance and set its names.
1017  */
1018 int usx2y_audio_create(struct snd_card *card)
1019 {
1020 	int err;
1021 
1022 	err = usx2y_audio_stream_new(card, 0xA, 0x8);
1023 	if (err < 0)
1024 		return err;
1025 	if (le16_to_cpu(usx2y(card)->dev->descriptor.idProduct) == USB_ID_US428) {
1026 		err = usx2y_audio_stream_new(card, 0, 0xA);
1027 		if (err < 0)
1028 			return err;
1029 	}
1030 	if (le16_to_cpu(usx2y(card)->dev->descriptor.idProduct) != USB_ID_US122)
1031 		err = usx2y_rate_set(usx2y(card), 44100);	// Lets us428 recognize output-volume settings, disturbs us122.
1032 	return err;
1033 }
1034