xref: /openbmc/linux/sound/usb/usx2y/usbusx2yaudio.c (revision a09d2831)
1 /*
2  *   US-X2Y AUDIO
3  *   Copyright (c) 2002-2004 by Karsten Wiese
4  *
5  *   based on
6  *
7  *   (Tentative) USB Audio Driver for ALSA
8  *
9  *   Main and PCM part
10  *
11  *   Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
12  *
13  *   Many codes borrowed from audio.c by
14  *	    Alan Cox (alan@lxorguk.ukuu.org.uk)
15  *	    Thomas Sailer (sailer@ife.ee.ethz.ch)
16  *
17  *
18  *   This program is free software; you can redistribute it and/or modify
19  *   it under the terms of the GNU General Public License as published by
20  *   the Free Software Foundation; either version 2 of the License, or
21  *   (at your option) any later version.
22  *
23  *   This program is distributed in the hope that it will be useful,
24  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
25  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
26  *   GNU General Public License for more details.
27  *
28  *   You should have received a copy of the GNU General Public License
29  *   along with this program; if not, write to the Free Software
30  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
31  */
32 
33 
34 #include <linux/interrupt.h>
35 #include <linux/usb.h>
36 #include <sound/core.h>
37 #include <sound/info.h>
38 #include <sound/pcm.h>
39 #include <sound/pcm_params.h>
40 #include "usx2y.h"
41 #include "usbusx2y.h"
42 
43 #define USX2Y_NRPACKS 4			/* Default value used for nr of packs per urb.
44 					  1 to 4 have been tested ok on uhci.
45 					  To use 3 on ohci, you'd need a patch:
46 					  look for "0000425-linux-2.6.9-rc4-mm1_ohci-hcd.patch.gz" on
47 					  "https://bugtrack.alsa-project.org/alsa-bug/bug_view_page.php?bug_id=0000425"
48 					  .
49 					  1, 2 and 4 work out of the box on ohci, if I recall correctly.
50 					  Bigger is safer operation,
51 					  smaller gives lower latencies.
52 					*/
53 #define USX2Y_NRPACKS_VARIABLE y	/* If your system works ok with this module's parameter
54 					   nrpacks set to 1, you might as well comment
55 					   this #define out, and thereby produce smaller, faster code.
56 					   You'd also set USX2Y_NRPACKS to 1 then.
57 					*/
58 
59 #ifdef USX2Y_NRPACKS_VARIABLE
60  static int nrpacks = USX2Y_NRPACKS; /* number of packets per urb */
61  #define  nr_of_packs() nrpacks
62  module_param(nrpacks, int, 0444);
63  MODULE_PARM_DESC(nrpacks, "Number of packets per URB.");
64 #else
65  #define nr_of_packs() USX2Y_NRPACKS
66 #endif
67 
68 
69 static int usX2Y_urb_capt_retire(struct snd_usX2Y_substream *subs)
70 {
71 	struct urb	*urb = subs->completed_urb;
72 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
73 	unsigned char	*cp;
74 	int 		i, len, lens = 0, hwptr_done = subs->hwptr_done;
75 	struct usX2Ydev	*usX2Y = subs->usX2Y;
76 
77 	for (i = 0; i < nr_of_packs(); i++) {
78 		cp = (unsigned char*)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
79 		if (urb->iso_frame_desc[i].status) { /* active? hmm, skip this */
80 			snd_printk(KERN_ERR "active frame status %i. "
81 				   "Most propably some hardware problem.\n",
82 				   urb->iso_frame_desc[i].status);
83 			return urb->iso_frame_desc[i].status;
84 		}
85 		len = urb->iso_frame_desc[i].actual_length / usX2Y->stride;
86 		if (! len) {
87 			snd_printd("0 == len ERROR!\n");
88 			continue;
89 		}
90 
91 		/* copy a data chunk */
92 		if ((hwptr_done + len) > runtime->buffer_size) {
93 			int cnt = runtime->buffer_size - hwptr_done;
94 			int blen = cnt * usX2Y->stride;
95 			memcpy(runtime->dma_area + hwptr_done * usX2Y->stride, cp, blen);
96 			memcpy(runtime->dma_area, cp + blen, len * usX2Y->stride - blen);
97 		} else {
98 			memcpy(runtime->dma_area + hwptr_done * usX2Y->stride, cp,
99 			       len * usX2Y->stride);
100 		}
101 		lens += len;
102 		if ((hwptr_done += len) >= runtime->buffer_size)
103 			hwptr_done -= runtime->buffer_size;
104 	}
105 
106 	subs->hwptr_done = hwptr_done;
107 	subs->transfer_done += lens;
108 	/* update the pointer, call callback if necessary */
109 	if (subs->transfer_done >= runtime->period_size) {
110 		subs->transfer_done -= runtime->period_size;
111 		snd_pcm_period_elapsed(subs->pcm_substream);
112 	}
113 	return 0;
114 }
115 /*
116  * prepare urb for playback data pipe
117  *
118  * we copy the data directly from the pcm buffer.
119  * the current position to be copied is held in hwptr field.
120  * since a urb can handle only a single linear buffer, if the total
121  * transferred area overflows the buffer boundary, we cannot send
122  * it directly from the buffer.  thus the data is once copied to
123  * a temporary buffer and urb points to that.
124  */
125 static int usX2Y_urb_play_prepare(struct snd_usX2Y_substream *subs,
126 				  struct urb *cap_urb,
127 				  struct urb *urb)
128 {
129 	int count, counts, pack;
130 	struct usX2Ydev *usX2Y = subs->usX2Y;
131 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
132 
133 	count = 0;
134 	for (pack = 0; pack <  nr_of_packs(); pack++) {
135 		/* calculate the size of a packet */
136 		counts = cap_urb->iso_frame_desc[pack].actual_length / usX2Y->stride;
137 		count += counts;
138 		if (counts < 43 || counts > 50) {
139 			snd_printk(KERN_ERR "should not be here with counts=%i\n", counts);
140 			return -EPIPE;
141 		}
142 		/* set up descriptor */
143 		urb->iso_frame_desc[pack].offset = pack ?
144 			urb->iso_frame_desc[pack - 1].offset +
145 			urb->iso_frame_desc[pack - 1].length :
146 			0;
147 		urb->iso_frame_desc[pack].length = cap_urb->iso_frame_desc[pack].actual_length;
148 	}
149 	if (atomic_read(&subs->state) >= state_PRERUNNING)
150 		if (subs->hwptr + count > runtime->buffer_size) {
151 			/* err, the transferred area goes over buffer boundary.
152 			 * copy the data to the temp buffer.
153 			 */
154 			int len;
155 			len = runtime->buffer_size - subs->hwptr;
156 			urb->transfer_buffer = subs->tmpbuf;
157 			memcpy(subs->tmpbuf, runtime->dma_area +
158 			       subs->hwptr * usX2Y->stride, len * usX2Y->stride);
159 			memcpy(subs->tmpbuf + len * usX2Y->stride,
160 			       runtime->dma_area, (count - len) * usX2Y->stride);
161 			subs->hwptr += count;
162 			subs->hwptr -= runtime->buffer_size;
163 		} else {
164 			/* set the buffer pointer */
165 			urb->transfer_buffer = runtime->dma_area + subs->hwptr * usX2Y->stride;
166 			if ((subs->hwptr += count) >= runtime->buffer_size)
167 			subs->hwptr -= runtime->buffer_size;
168 		}
169 	else
170 		urb->transfer_buffer = subs->tmpbuf;
171 	urb->transfer_buffer_length = count * usX2Y->stride;
172 	return 0;
173 }
174 
175 /*
176  * process after playback data complete
177  *
178  * update the current position and call callback if a period is processed.
179  */
180 static void usX2Y_urb_play_retire(struct snd_usX2Y_substream *subs, struct urb *urb)
181 {
182 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
183 	int		len = urb->actual_length / subs->usX2Y->stride;
184 
185 	subs->transfer_done += len;
186 	subs->hwptr_done +=  len;
187 	if (subs->hwptr_done >= runtime->buffer_size)
188 		subs->hwptr_done -= runtime->buffer_size;
189 	if (subs->transfer_done >= runtime->period_size) {
190 		subs->transfer_done -= runtime->period_size;
191 		snd_pcm_period_elapsed(subs->pcm_substream);
192 	}
193 }
194 
195 static int usX2Y_urb_submit(struct snd_usX2Y_substream *subs, struct urb *urb, int frame)
196 {
197 	int err;
198 	if (!urb)
199 		return -ENODEV;
200 	urb->start_frame = (frame + NRURBS * nr_of_packs());  // let hcd do rollover sanity checks
201 	urb->hcpriv = NULL;
202 	urb->dev = subs->usX2Y->dev; /* we need to set this at each time */
203 	if ((err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
204 		snd_printk(KERN_ERR "usb_submit_urb() returned %i\n", err);
205 		return err;
206 	}
207 	return 0;
208 }
209 
210 static inline int usX2Y_usbframe_complete(struct snd_usX2Y_substream *capsubs,
211 					  struct snd_usX2Y_substream *playbacksubs,
212 					  int frame)
213 {
214 	int err, state;
215 	struct urb *urb = playbacksubs->completed_urb;
216 
217 	state = atomic_read(&playbacksubs->state);
218 	if (NULL != urb) {
219 		if (state == state_RUNNING)
220 			usX2Y_urb_play_retire(playbacksubs, urb);
221 		else if (state >= state_PRERUNNING)
222 			atomic_inc(&playbacksubs->state);
223 	} else {
224 		switch (state) {
225 		case state_STARTING1:
226 			urb = playbacksubs->urb[0];
227 			atomic_inc(&playbacksubs->state);
228 			break;
229 		case state_STARTING2:
230 			urb = playbacksubs->urb[1];
231 			atomic_inc(&playbacksubs->state);
232 			break;
233 		}
234 	}
235 	if (urb) {
236 		if ((err = usX2Y_urb_play_prepare(playbacksubs, capsubs->completed_urb, urb)) ||
237 		    (err = usX2Y_urb_submit(playbacksubs, urb, frame))) {
238 			return err;
239 		}
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 			if ((err = usX2Y_urb_capt_retire(capsubs)))
248 				return err;
249 		} else if (state >= state_PRERUNNING)
250 			atomic_inc(&capsubs->state);
251 		if ((err = usX2Y_urb_submit(capsubs, capsubs->completed_urb, frame)))
252 			return err;
253 	}
254 	capsubs->completed_urb = NULL;
255 	return 0;
256 }
257 
258 
259 static void usX2Y_clients_stop(struct usX2Ydev *usX2Y)
260 {
261 	int s, u;
262 
263 	for (s = 0; s < 4; s++) {
264 		struct snd_usX2Y_substream *subs = usX2Y->subs[s];
265 		if (subs) {
266 			snd_printdd("%i %p state=%i\n", s, subs, atomic_read(&subs->state));
267 			atomic_set(&subs->state, state_STOPPED);
268 		}
269 	}
270 	for (s = 0; s < 4; s++) {
271 		struct snd_usX2Y_substream *subs = usX2Y->subs[s];
272 		if (subs) {
273 			if (atomic_read(&subs->state) >= state_PRERUNNING) {
274 				snd_pcm_stop(subs->pcm_substream, SNDRV_PCM_STATE_XRUN);
275 			}
276 			for (u = 0; u < NRURBS; u++) {
277 				struct urb *urb = subs->urb[u];
278 				if (NULL != 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 usX2Y_error_sequence(struct usX2Ydev *usX2Y,
297 				 struct snd_usX2Y_substream *subs, struct urb *urb)
298 {
299 	snd_printk(KERN_ERR
300 "Sequence Error!(hcd_frame=%i ep=%i%s;wait=%i,frame=%i).\n"
301 "Most propably some urb of usb-frame %i is still missing.\n"
302 "Cause could be too long delays in usb-hcd interrupt handling.\n",
303 		   usb_get_current_frame_number(usX2Y->dev),
304 		   subs->endpoint, usb_pipein(urb->pipe) ? "in" : "out",
305 		   usX2Y->wait_iso_frame, urb->start_frame, usX2Y->wait_iso_frame);
306 	usX2Y_clients_stop(usX2Y);
307 }
308 
309 static void i_usX2Y_urb_complete(struct urb *urb)
310 {
311 	struct snd_usX2Y_substream *subs = urb->context;
312 	struct usX2Ydev *usX2Y = subs->usX2Y;
313 
314 	if (unlikely(atomic_read(&subs->state) < state_PREPARED)) {
315 		snd_printdd("hcd_frame=%i ep=%i%s status=%i start_frame=%i\n",
316 			    usb_get_current_frame_number(usX2Y->dev),
317 			    subs->endpoint, usb_pipein(urb->pipe) ? "in" : "out",
318 			    urb->status, urb->start_frame);
319 		return;
320 	}
321 	if (unlikely(urb->status)) {
322 		usX2Y_error_urb_status(usX2Y, subs, urb);
323 		return;
324 	}
325 	if (likely((urb->start_frame & 0xFFFF) == (usX2Y->wait_iso_frame & 0xFFFF)))
326 		subs->completed_urb = urb;
327 	else {
328 		usX2Y_error_sequence(usX2Y, subs, urb);
329 		return;
330 	}
331 	{
332 		struct snd_usX2Y_substream *capsubs = usX2Y->subs[SNDRV_PCM_STREAM_CAPTURE],
333 			*playbacksubs = usX2Y->subs[SNDRV_PCM_STREAM_PLAYBACK];
334 		if (capsubs->completed_urb &&
335 		    atomic_read(&capsubs->state) >= state_PREPARED &&
336 		    (playbacksubs->completed_urb ||
337 		     atomic_read(&playbacksubs->state) < state_PREPARED)) {
338 			if (!usX2Y_usbframe_complete(capsubs, playbacksubs, urb->start_frame))
339 				usX2Y->wait_iso_frame += nr_of_packs();
340 			else {
341 				snd_printdd("\n");
342 				usX2Y_clients_stop(usX2Y);
343 			}
344 		}
345 	}
346 }
347 
348 static void usX2Y_urbs_set_complete(struct usX2Ydev * usX2Y,
349 				    void (*complete)(struct urb *))
350 {
351 	int s, u;
352 	for (s = 0; s < 4; s++) {
353 		struct snd_usX2Y_substream *subs = usX2Y->subs[s];
354 		if (NULL != subs)
355 			for (u = 0; u < NRURBS; u++) {
356 				struct urb * urb = subs->urb[u];
357 				if (NULL != urb)
358 					urb->complete = complete;
359 			}
360 	}
361 }
362 
363 static void usX2Y_subs_startup_finish(struct usX2Ydev * usX2Y)
364 {
365 	usX2Y_urbs_set_complete(usX2Y, i_usX2Y_urb_complete);
366 	usX2Y->prepare_subs = NULL;
367 }
368 
369 static void i_usX2Y_subs_startup(struct urb *urb)
370 {
371 	struct snd_usX2Y_substream *subs = urb->context;
372 	struct usX2Ydev *usX2Y = subs->usX2Y;
373 	struct snd_usX2Y_substream *prepare_subs = usX2Y->prepare_subs;
374 	if (NULL != prepare_subs)
375 		if (urb->start_frame == prepare_subs->urb[0]->start_frame) {
376 			usX2Y_subs_startup_finish(usX2Y);
377 			atomic_inc(&prepare_subs->state);
378 			wake_up(&usX2Y->prepare_wait_queue);
379 		}
380 
381 	i_usX2Y_urb_complete(urb);
382 }
383 
384 static void usX2Y_subs_prepare(struct snd_usX2Y_substream *subs)
385 {
386 	snd_printdd("usX2Y_substream_prepare(%p) ep=%i urb0=%p urb1=%p\n",
387 		    subs, subs->endpoint, subs->urb[0], subs->urb[1]);
388 	/* reset the pointer */
389 	subs->hwptr = 0;
390 	subs->hwptr_done = 0;
391 	subs->transfer_done = 0;
392 }
393 
394 
395 static void usX2Y_urb_release(struct urb **urb, int free_tb)
396 {
397 	if (*urb) {
398 		usb_kill_urb(*urb);
399 		if (free_tb)
400 			kfree((*urb)->transfer_buffer);
401 		usb_free_urb(*urb);
402 		*urb = NULL;
403 	}
404 }
405 /*
406  * release a substreams urbs
407  */
408 static void usX2Y_urbs_release(struct snd_usX2Y_substream *subs)
409 {
410 	int i;
411 	snd_printdd("usX2Y_urbs_release() %i\n", subs->endpoint);
412 	for (i = 0; i < NRURBS; i++)
413 		usX2Y_urb_release(subs->urb + i,
414 				  subs != subs->usX2Y->subs[SNDRV_PCM_STREAM_PLAYBACK]);
415 
416 	kfree(subs->tmpbuf);
417 	subs->tmpbuf = NULL;
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 
429 	pipe = is_playback ? usb_sndisocpipe(dev, subs->endpoint) :
430 			usb_rcvisocpipe(dev, subs->endpoint);
431 	subs->maxpacksize = usb_maxpacket(dev, pipe, is_playback);
432 	if (!subs->maxpacksize)
433 		return -EINVAL;
434 
435 	if (is_playback && NULL == subs->tmpbuf) {	/* allocate a temporary buffer for playback */
436 		subs->tmpbuf = kcalloc(nr_of_packs(), subs->maxpacksize, GFP_KERNEL);
437 		if (NULL == subs->tmpbuf) {
438 			snd_printk(KERN_ERR "cannot malloc tmpbuf\n");
439 			return -ENOMEM;
440 		}
441 	}
442 	/* allocate and initialize data urbs */
443 	for (i = 0; i < NRURBS; i++) {
444 		struct urb **purb = subs->urb + i;
445 		if (*purb) {
446 			usb_kill_urb(*purb);
447 			continue;
448 		}
449 		*purb = usb_alloc_urb(nr_of_packs(), GFP_KERNEL);
450 		if (NULL == *purb) {
451 			usX2Y_urbs_release(subs);
452 			return -ENOMEM;
453 		}
454 		if (!is_playback && !(*purb)->transfer_buffer) {
455 			/* allocate a capture buffer per urb */
456 			(*purb)->transfer_buffer = kmalloc(subs->maxpacksize * nr_of_packs(), GFP_KERNEL);
457 			if (NULL == (*purb)->transfer_buffer) {
458 				usX2Y_urbs_release(subs);
459 				return -ENOMEM;
460 			}
461 		}
462 		(*purb)->dev = dev;
463 		(*purb)->pipe = pipe;
464 		(*purb)->number_of_packets = nr_of_packs();
465 		(*purb)->context = subs;
466 		(*purb)->interval = 1;
467 		(*purb)->complete = i_usX2Y_subs_startup;
468 	}
469 	return 0;
470 }
471 
472 static void usX2Y_subs_startup(struct snd_usX2Y_substream *subs)
473 {
474 	struct usX2Ydev *usX2Y = subs->usX2Y;
475 	usX2Y->prepare_subs = subs;
476 	subs->urb[0]->start_frame = -1;
477 	wmb();
478 	usX2Y_urbs_set_complete(usX2Y, i_usX2Y_subs_startup);
479 }
480 
481 static int usX2Y_urbs_start(struct snd_usX2Y_substream *subs)
482 {
483 	int i, err;
484 	struct usX2Ydev *usX2Y = subs->usX2Y;
485 
486 	if ((err = usX2Y_urbs_allocate(subs)) < 0)
487 		return err;
488 	subs->completed_urb = NULL;
489 	for (i = 0; i < 4; i++) {
490 		struct snd_usX2Y_substream *subs = usX2Y->subs[i];
491 		if (subs != NULL && atomic_read(&subs->state) >= state_PREPARED)
492 			goto start;
493 	}
494 
495  start:
496 	usX2Y_subs_startup(subs);
497 	for (i = 0; i < NRURBS; i++) {
498 		struct urb *urb = subs->urb[i];
499 		if (usb_pipein(urb->pipe)) {
500 			unsigned long pack;
501 			if (0 == i)
502 				atomic_set(&subs->state, state_STARTING3);
503 			urb->dev = usX2Y->dev;
504 			urb->transfer_flags = URB_ISO_ASAP;
505 			for (pack = 0; pack < nr_of_packs(); pack++) {
506 				urb->iso_frame_desc[pack].offset = subs->maxpacksize * pack;
507 				urb->iso_frame_desc[pack].length = subs->maxpacksize;
508 			}
509 			urb->transfer_buffer_length = subs->maxpacksize * nr_of_packs();
510 			if ((err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
511 				snd_printk (KERN_ERR "cannot submit datapipe for urb %d, err = %d\n", i, err);
512 				err = -EPIPE;
513 				goto cleanup;
514 			} else
515 				if (i == 0)
516 					usX2Y->wait_iso_frame = urb->start_frame;
517 			urb->transfer_flags = 0;
518 		} else {
519 			atomic_set(&subs->state, state_STARTING1);
520 			break;
521 		}
522 	}
523 	err = 0;
524 	wait_event(usX2Y->prepare_wait_queue, NULL == usX2Y->prepare_subs);
525 	if (atomic_read(&subs->state) != state_PREPARED)
526 		err = -EPIPE;
527 
528  cleanup:
529 	if (err) {
530 		usX2Y_subs_startup_finish(usX2Y);
531 		usX2Y_clients_stop(usX2Y);		// something is completely wroong > stop evrything
532 	}
533 	return err;
534 }
535 
536 /*
537  * return the current pcm pointer.  just return the hwptr_done value.
538  */
539 static snd_pcm_uframes_t snd_usX2Y_pcm_pointer(struct snd_pcm_substream *substream)
540 {
541 	struct snd_usX2Y_substream *subs = substream->runtime->private_data;
542 	return subs->hwptr_done;
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("snd_usX2Y_pcm_trigger(START)\n");
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("snd_usX2Y_pcm_trigger(STOP)\n");
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 /*
575  * allocate a buffer, setup samplerate
576  *
577  * so far we use a physically linear buffer although packetize transfer
578  * doesn't need a continuous area.
579  * if sg buffer is supported on the later version of alsa, we'll follow
580  * that.
581  */
582 static struct s_c2
583 {
584 	char c1, c2;
585 }
586 	SetRate44100[] =
587 {
588 	{ 0x14, 0x08},	// this line sets 44100, well actually a little less
589 	{ 0x18, 0x40},	// only tascam / frontier design knows the further lines .......
590 	{ 0x18, 0x42},
591 	{ 0x18, 0x45},
592 	{ 0x18, 0x46},
593 	{ 0x18, 0x48},
594 	{ 0x18, 0x4A},
595 	{ 0x18, 0x4C},
596 	{ 0x18, 0x4E},
597 	{ 0x18, 0x50},
598 	{ 0x18, 0x52},
599 	{ 0x18, 0x54},
600 	{ 0x18, 0x56},
601 	{ 0x18, 0x58},
602 	{ 0x18, 0x5A},
603 	{ 0x18, 0x5C},
604 	{ 0x18, 0x5E},
605 	{ 0x18, 0x60},
606 	{ 0x18, 0x62},
607 	{ 0x18, 0x64},
608 	{ 0x18, 0x66},
609 	{ 0x18, 0x68},
610 	{ 0x18, 0x6A},
611 	{ 0x18, 0x6C},
612 	{ 0x18, 0x6E},
613 	{ 0x18, 0x70},
614 	{ 0x18, 0x72},
615 	{ 0x18, 0x74},
616 	{ 0x18, 0x76},
617 	{ 0x18, 0x78},
618 	{ 0x18, 0x7A},
619 	{ 0x18, 0x7C},
620 	{ 0x18, 0x7E}
621 };
622 static struct s_c2 SetRate48000[] =
623 {
624 	{ 0x14, 0x09},	// this line sets 48000, well actually a little less
625 	{ 0x18, 0x40},	// only tascam / frontier design knows the further lines .......
626 	{ 0x18, 0x42},
627 	{ 0x18, 0x45},
628 	{ 0x18, 0x46},
629 	{ 0x18, 0x48},
630 	{ 0x18, 0x4A},
631 	{ 0x18, 0x4C},
632 	{ 0x18, 0x4E},
633 	{ 0x18, 0x50},
634 	{ 0x18, 0x52},
635 	{ 0x18, 0x54},
636 	{ 0x18, 0x56},
637 	{ 0x18, 0x58},
638 	{ 0x18, 0x5A},
639 	{ 0x18, 0x5C},
640 	{ 0x18, 0x5E},
641 	{ 0x18, 0x60},
642 	{ 0x18, 0x62},
643 	{ 0x18, 0x64},
644 	{ 0x18, 0x66},
645 	{ 0x18, 0x68},
646 	{ 0x18, 0x6A},
647 	{ 0x18, 0x6C},
648 	{ 0x18, 0x6E},
649 	{ 0x18, 0x70},
650 	{ 0x18, 0x73},
651 	{ 0x18, 0x74},
652 	{ 0x18, 0x76},
653 	{ 0x18, 0x78},
654 	{ 0x18, 0x7A},
655 	{ 0x18, 0x7C},
656 	{ 0x18, 0x7E}
657 };
658 #define NOOF_SETRATE_URBS ARRAY_SIZE(SetRate48000)
659 
660 static void i_usX2Y_04Int(struct urb *urb)
661 {
662 	struct usX2Ydev *usX2Y = urb->context;
663 
664 	if (urb->status)
665 		snd_printk(KERN_ERR "snd_usX2Y_04Int() urb->status=%i\n", urb->status);
666 	if (0 == --usX2Y->US04->len)
667 		wake_up(&usX2Y->In04WaitQueue);
668 }
669 
670 static int usX2Y_rate_set(struct usX2Ydev *usX2Y, int rate)
671 {
672 	int			err = 0, i;
673 	struct snd_usX2Y_urbSeq	*us = NULL;
674 	int			*usbdata = NULL;
675 	struct s_c2		*ra = rate == 48000 ? SetRate48000 : SetRate44100;
676 
677 	if (usX2Y->rate != rate) {
678 		us = kzalloc(sizeof(*us) + sizeof(struct urb*) * NOOF_SETRATE_URBS, GFP_KERNEL);
679 		if (NULL == us) {
680 			err = -ENOMEM;
681 			goto cleanup;
682 		}
683 		usbdata = kmalloc(sizeof(int) * NOOF_SETRATE_URBS, GFP_KERNEL);
684 		if (NULL == usbdata) {
685 			err = -ENOMEM;
686 			goto cleanup;
687 		}
688 		for (i = 0; i < NOOF_SETRATE_URBS; ++i) {
689 			if (NULL == (us->urb[i] = usb_alloc_urb(0, GFP_KERNEL))) {
690 				err = -ENOMEM;
691 				goto cleanup;
692 			}
693 			((char*)(usbdata + i))[0] = ra[i].c1;
694 			((char*)(usbdata + i))[1] = ra[i].c2;
695 			usb_fill_bulk_urb(us->urb[i], usX2Y->dev, usb_sndbulkpipe(usX2Y->dev, 4),
696 					  usbdata + i, 2, i_usX2Y_04Int, usX2Y);
697 #ifdef OLD_USB
698 			us->urb[i]->transfer_flags = USB_QUEUE_BULK;
699 #endif
700 		}
701 		us->submitted =	0;
702 		us->len =	NOOF_SETRATE_URBS;
703 		usX2Y->US04 =	us;
704 		wait_event_timeout(usX2Y->In04WaitQueue, 0 == us->len, HZ);
705 		usX2Y->US04 =	NULL;
706 		if (us->len)
707 			err = -ENODEV;
708 	cleanup:
709 		if (us) {
710 			us->submitted =	2*NOOF_SETRATE_URBS;
711 			for (i = 0; i < NOOF_SETRATE_URBS; ++i) {
712 				struct urb *urb = us->urb[i];
713 				if (urb->status) {
714 					if (!err)
715 						err = -ENODEV;
716 					usb_kill_urb(urb);
717 				}
718 				usb_free_urb(urb);
719 			}
720 			usX2Y->US04 = NULL;
721 			kfree(usbdata);
722 			kfree(us);
723 			if (!err)
724 				usX2Y->rate = rate;
725 		}
726 	}
727 
728 	return err;
729 }
730 
731 
732 static int usX2Y_format_set(struct usX2Ydev *usX2Y, snd_pcm_format_t format)
733 {
734 	int alternate, err;
735 	struct list_head* p;
736 	if (format == SNDRV_PCM_FORMAT_S24_3LE) {
737 		alternate = 2;
738 		usX2Y->stride = 6;
739 	} else {
740 		alternate = 1;
741 		usX2Y->stride = 4;
742 	}
743 	list_for_each(p, &usX2Y->midi_list) {
744 		snd_usbmidi_input_stop(p);
745 	}
746 	usb_kill_urb(usX2Y->In04urb);
747 	if ((err = usb_set_interface(usX2Y->dev, 0, alternate))) {
748 		snd_printk(KERN_ERR "usb_set_interface error \n");
749 		return err;
750 	}
751 	usX2Y->In04urb->dev = usX2Y->dev;
752 	err = usb_submit_urb(usX2Y->In04urb, GFP_KERNEL);
753 	list_for_each(p, &usX2Y->midi_list) {
754 		snd_usbmidi_input_start(p);
755 	}
756 	usX2Y->format = format;
757 	usX2Y->rate = 0;
758 	return err;
759 }
760 
761 
762 static int snd_usX2Y_pcm_hw_params(struct snd_pcm_substream *substream,
763 				   struct snd_pcm_hw_params *hw_params)
764 {
765 	int			err = 0;
766 	unsigned int		rate = params_rate(hw_params);
767 	snd_pcm_format_t	format = params_format(hw_params);
768 	struct snd_card *card = substream->pstr->pcm->card;
769 	struct list_head *list;
770 
771 	snd_printdd("snd_usX2Y_hw_params(%p, %p)\n", substream, hw_params);
772 	// all pcm substreams off one usX2Y have to operate at the same rate & format
773 	list_for_each(list, &card->devices) {
774 		struct snd_device *dev;
775 		struct snd_pcm *pcm;
776 		int s;
777 		dev = snd_device(list);
778 		if (dev->type != SNDRV_DEV_PCM)
779 			continue;
780 		pcm = dev->device_data;
781 		for (s = 0; s < 2; ++s) {
782 			struct snd_pcm_substream *test_substream;
783 			test_substream = pcm->streams[s].substream;
784 			if (test_substream && test_substream != substream  &&
785 			    test_substream->runtime &&
786 			    ((test_substream->runtime->format &&
787 			      test_substream->runtime->format != format) ||
788 			     (test_substream->runtime->rate &&
789 			      test_substream->runtime->rate != rate)))
790 				return -EINVAL;
791 		}
792 	}
793 	if (0 > (err = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params)))) {
794 		snd_printk(KERN_ERR "snd_pcm_lib_malloc_pages(%p, %i) returned %i\n",
795 			   substream, params_buffer_bytes(hw_params), err);
796 		return err;
797 	}
798 	return 0;
799 }
800 
801 /*
802  * free the buffer
803  */
804 static int snd_usX2Y_pcm_hw_free(struct snd_pcm_substream *substream)
805 {
806 	struct snd_pcm_runtime *runtime = substream->runtime;
807 	struct snd_usX2Y_substream *subs = runtime->private_data;
808 	mutex_lock(&subs->usX2Y->prepare_mutex);
809 	snd_printdd("snd_usX2Y_hw_free(%p)\n", substream);
810 
811 	if (SNDRV_PCM_STREAM_PLAYBACK == substream->stream) {
812 		struct snd_usX2Y_substream *cap_subs = subs->usX2Y->subs[SNDRV_PCM_STREAM_CAPTURE];
813 		atomic_set(&subs->state, state_STOPPED);
814 		usX2Y_urbs_release(subs);
815 		if (!cap_subs->pcm_substream ||
816 		    !cap_subs->pcm_substream->runtime ||
817 		    !cap_subs->pcm_substream->runtime->status ||
818 		    cap_subs->pcm_substream->runtime->status->state < SNDRV_PCM_STATE_PREPARED) {
819 			atomic_set(&cap_subs->state, state_STOPPED);
820 			usX2Y_urbs_release(cap_subs);
821 		}
822 	} else {
823 		struct snd_usX2Y_substream *playback_subs = subs->usX2Y->subs[SNDRV_PCM_STREAM_PLAYBACK];
824 		if (atomic_read(&playback_subs->state) < state_PREPARED) {
825 			atomic_set(&subs->state, state_STOPPED);
826 			usX2Y_urbs_release(subs);
827 		}
828 	}
829 	mutex_unlock(&subs->usX2Y->prepare_mutex);
830 	return snd_pcm_lib_free_pages(substream);
831 }
832 /*
833  * prepare callback
834  *
835  * set format and initialize urbs
836  */
837 static int snd_usX2Y_pcm_prepare(struct snd_pcm_substream *substream)
838 {
839 	struct snd_pcm_runtime *runtime = substream->runtime;
840 	struct snd_usX2Y_substream *subs = runtime->private_data;
841 	struct usX2Ydev *usX2Y = subs->usX2Y;
842 	struct snd_usX2Y_substream *capsubs = subs->usX2Y->subs[SNDRV_PCM_STREAM_CAPTURE];
843 	int err = 0;
844 	snd_printdd("snd_usX2Y_pcm_prepare(%p)\n", substream);
845 
846 	mutex_lock(&usX2Y->prepare_mutex);
847 	usX2Y_subs_prepare(subs);
848 // Start hardware streams
849 // SyncStream first....
850 	if (atomic_read(&capsubs->state) < state_PREPARED) {
851 		if (usX2Y->format != runtime->format)
852 			if ((err = usX2Y_format_set(usX2Y, runtime->format)) < 0)
853 				goto up_prepare_mutex;
854 		if (usX2Y->rate != runtime->rate)
855 			if ((err = usX2Y_rate_set(usX2Y, runtime->rate)) < 0)
856 				goto up_prepare_mutex;
857 		snd_printdd("starting capture pipe for %s\n", subs == capsubs ? "self" : "playpipe");
858 		if (0 > (err = usX2Y_urbs_start(capsubs)))
859 			goto up_prepare_mutex;
860 	}
861 
862 	if (subs != capsubs && atomic_read(&subs->state) < state_PREPARED)
863 		err = usX2Y_urbs_start(subs);
864 
865  up_prepare_mutex:
866 	mutex_unlock(&usX2Y->prepare_mutex);
867 	return err;
868 }
869 
870 static struct snd_pcm_hardware snd_usX2Y_2c =
871 {
872 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
873 				 SNDRV_PCM_INFO_BLOCK_TRANSFER |
874 				 SNDRV_PCM_INFO_MMAP_VALID |
875 				 SNDRV_PCM_INFO_BATCH),
876 	.formats =                 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_3LE,
877 	.rates =                   SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000,
878 	.rate_min =                44100,
879 	.rate_max =                48000,
880 	.channels_min =            2,
881 	.channels_max =            2,
882 	.buffer_bytes_max =	(2*128*1024),
883 	.period_bytes_min =	64,
884 	.period_bytes_max =	(128*1024),
885 	.periods_min =		2,
886 	.periods_max =		1024,
887 	.fifo_size =              0
888 };
889 
890 
891 
892 static int snd_usX2Y_pcm_open(struct snd_pcm_substream *substream)
893 {
894 	struct snd_usX2Y_substream	*subs = ((struct snd_usX2Y_substream **)
895 					 snd_pcm_substream_chip(substream))[substream->stream];
896 	struct snd_pcm_runtime	*runtime = substream->runtime;
897 
898 	if (subs->usX2Y->chip_status & USX2Y_STAT_CHIP_MMAP_PCM_URBS)
899 		return -EBUSY;
900 
901 	runtime->hw = snd_usX2Y_2c;
902 	runtime->private_data = subs;
903 	subs->pcm_substream = substream;
904 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME, 1000, 200000);
905 	return 0;
906 }
907 
908 
909 
910 static int snd_usX2Y_pcm_close(struct snd_pcm_substream *substream)
911 {
912 	struct snd_pcm_runtime *runtime = substream->runtime;
913 	struct snd_usX2Y_substream *subs = runtime->private_data;
914 
915 	subs->pcm_substream = NULL;
916 
917 	return 0;
918 }
919 
920 
921 static struct snd_pcm_ops snd_usX2Y_pcm_ops =
922 {
923 	.open =		snd_usX2Y_pcm_open,
924 	.close =	snd_usX2Y_pcm_close,
925 	.ioctl =	snd_pcm_lib_ioctl,
926 	.hw_params =	snd_usX2Y_pcm_hw_params,
927 	.hw_free =	snd_usX2Y_pcm_hw_free,
928 	.prepare =	snd_usX2Y_pcm_prepare,
929 	.trigger =	snd_usX2Y_pcm_trigger,
930 	.pointer =	snd_usX2Y_pcm_pointer,
931 };
932 
933 
934 /*
935  * free a usb stream instance
936  */
937 static void usX2Y_audio_stream_free(struct snd_usX2Y_substream **usX2Y_substream)
938 {
939 	kfree(usX2Y_substream[SNDRV_PCM_STREAM_PLAYBACK]);
940 	usX2Y_substream[SNDRV_PCM_STREAM_PLAYBACK] = NULL;
941 
942 	kfree(usX2Y_substream[SNDRV_PCM_STREAM_CAPTURE]);
943 	usX2Y_substream[SNDRV_PCM_STREAM_CAPTURE] = NULL;
944 }
945 
946 static void snd_usX2Y_pcm_private_free(struct snd_pcm *pcm)
947 {
948 	struct snd_usX2Y_substream **usX2Y_stream = pcm->private_data;
949 	if (usX2Y_stream)
950 		usX2Y_audio_stream_free(usX2Y_stream);
951 }
952 
953 static int usX2Y_audio_stream_new(struct snd_card *card, int playback_endpoint, int capture_endpoint)
954 {
955 	struct snd_pcm *pcm;
956 	int err, i;
957 	struct snd_usX2Y_substream **usX2Y_substream =
958 		usX2Y(card)->subs + 2 * usX2Y(card)->pcm_devs;
959 
960 	for (i = playback_endpoint ? SNDRV_PCM_STREAM_PLAYBACK : SNDRV_PCM_STREAM_CAPTURE;
961 	     i <= SNDRV_PCM_STREAM_CAPTURE; ++i) {
962 		usX2Y_substream[i] = kzalloc(sizeof(struct snd_usX2Y_substream), GFP_KERNEL);
963 		if (NULL == usX2Y_substream[i]) {
964 			snd_printk(KERN_ERR "cannot malloc\n");
965 			return -ENOMEM;
966 		}
967 		usX2Y_substream[i]->usX2Y = usX2Y(card);
968 	}
969 
970 	if (playback_endpoint)
971 		usX2Y_substream[SNDRV_PCM_STREAM_PLAYBACK]->endpoint = playback_endpoint;
972 	usX2Y_substream[SNDRV_PCM_STREAM_CAPTURE]->endpoint = capture_endpoint;
973 
974 	err = snd_pcm_new(card, NAME_ALLCAPS" Audio", usX2Y(card)->pcm_devs,
975 			  playback_endpoint ? 1 : 0, 1,
976 			  &pcm);
977 	if (err < 0) {
978 		usX2Y_audio_stream_free(usX2Y_substream);
979 		return err;
980 	}
981 
982 	if (playback_endpoint)
983 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_usX2Y_pcm_ops);
984 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_usX2Y_pcm_ops);
985 
986 	pcm->private_data = usX2Y_substream;
987 	pcm->private_free = snd_usX2Y_pcm_private_free;
988 	pcm->info_flags = 0;
989 
990 	sprintf(pcm->name, NAME_ALLCAPS" Audio #%d", usX2Y(card)->pcm_devs);
991 
992 	if ((playback_endpoint &&
993 	     0 > (err = snd_pcm_lib_preallocate_pages(pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream,
994 						     SNDRV_DMA_TYPE_CONTINUOUS,
995 						     snd_dma_continuous_data(GFP_KERNEL),
996 						     64*1024, 128*1024))) ||
997 	    0 > (err = snd_pcm_lib_preallocate_pages(pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream,
998 	    					     SNDRV_DMA_TYPE_CONTINUOUS,
999 	    					     snd_dma_continuous_data(GFP_KERNEL),
1000 						     64*1024, 128*1024))) {
1001 		snd_usX2Y_pcm_private_free(pcm);
1002 		return err;
1003 	}
1004 	usX2Y(card)->pcm_devs++;
1005 
1006 	return 0;
1007 }
1008 
1009 /*
1010  * create a chip instance and set its names.
1011  */
1012 int usX2Y_audio_create(struct snd_card *card)
1013 {
1014 	int err = 0;
1015 
1016 	INIT_LIST_HEAD(&usX2Y(card)->pcm_list);
1017 
1018 	if (0 > (err = usX2Y_audio_stream_new(card, 0xA, 0x8)))
1019 		return err;
1020 	if (le16_to_cpu(usX2Y(card)->dev->descriptor.idProduct) == USB_ID_US428)
1021 	     if (0 > (err = usX2Y_audio_stream_new(card, 0, 0xA)))
1022 		     return err;
1023 	if (le16_to_cpu(usX2Y(card)->dev->descriptor.idProduct) != USB_ID_US122)
1024 		err = usX2Y_rate_set(usX2Y(card), 44100);	// Lets us428 recognize output-volume settings, disturbs us122.
1025 	return err;
1026 }
1027