[ALSA] [ML403-AC97CR] Fix capture/periodic overrun bug
[linux-2.6.git] / sound / drivers / pcm-indirect2.c
1 /*
2  * Helper functions for indirect PCM data transfer to a simple FIFO in
3  * hardware (small, no possibility to read "hardware io position",
4  * updating position done by interrupt, ...)
5  *
6  *  Copyright (c) by 2007  Joachim Foerster <JOFT@gmx.de>
7  *
8  *  Based on "pcm-indirect.h" (alsa-driver-1.0.13) by
9  *
10  *  Copyright (c) by Takashi Iwai <tiwai@suse.de>
11  *                   Jaroslav Kysela <perex@suse.cz>
12  *
13  *   This program is free software; you can redistribute it and/or modify
14  *   it under the terms of the GNU General Public License as published by
15  *   the Free Software Foundation; either version 2 of the License, or
16  *   (at your option) any later version.
17  *
18  *   This program is distributed in the hope that it will be useful,
19  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
20  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  *   GNU General Public License for more details.
22  *
23  *   You should have received a copy of the GNU General Public License
24  *   along with this program; if not, write to the Free Software
25  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26  */
27
28 /* #dependency of sound/core.h# */
29 #include <sound/driver.h>
30 /* snd_printk/d() */
31 #include <sound/core.h>
32 /* struct snd_pcm_substream, struct snd_pcm_runtime, snd_pcm_uframes_t
33  * snd_pcm_period_elapsed() */
34 #include <sound/pcm.h>
35
36 #include "pcm-indirect2.h"
37
38 #ifdef SND_PCM_INDIRECT2_STAT
39 /* jiffies */
40 #include <linux/jiffies.h>
41
42 void snd_pcm_indirect2_stat(struct snd_pcm_substream *substream,
43                             struct snd_pcm_indirect2 *rec)
44 {
45         struct snd_pcm_runtime *runtime = substream->runtime;
46         int i;
47         int j;
48         int k;
49         int seconds = (rec->lastbytetime - rec->firstbytetime) / HZ;
50
51         snd_printk(KERN_DEBUG "STAT: mul_elapsed: %u, mul_elapsed_real: %d, "
52                    "irq_occured: %d\n",
53                    rec->mul_elapsed, rec->mul_elapsed_real, rec->irq_occured);
54         snd_printk(KERN_DEBUG "STAT: min_multiple: %d (irqs/period)\n",
55                    rec->min_multiple);
56         snd_printk(KERN_DEBUG "STAT: firstbytetime: %lu, lastbytetime: %lu, "
57                    "firstzerotime: %lu\n",
58                  rec->firstbytetime, rec->lastbytetime, rec->firstzerotime);
59         snd_printk(KERN_DEBUG "STAT: bytes2hw: %u Bytes => (by runtime->rate) "
60                    "length: %d s\n",
61                  rec->bytes2hw, rec->bytes2hw / 2 / 2 / runtime->rate);
62         snd_printk(KERN_DEBUG "STAT: (by measurement) length: %d => "
63                    "rate: %d Bytes/s = %d Frames/s|Hz\n",
64                    seconds, rec->bytes2hw / seconds,
65                    rec->bytes2hw / 2 / 2 / seconds);
66         snd_printk(KERN_DEBUG
67                    "STAT: zeros2hw: %u = %d ms ~ %d * %d zero copies\n",
68                    rec->zeros2hw, ((rec->zeros2hw / 2 / 2) * 1000) /
69                    runtime->rate,
70                    rec->zeros2hw / (rec->hw_buffer_size / 2),
71                    (rec->hw_buffer_size / 2));
72         snd_printk(KERN_DEBUG "STAT: pointer_calls: %u, lastdifftime: %u\n",
73                    rec->pointer_calls, rec->lastdifftime);
74         snd_printk(KERN_DEBUG "STAT: sw_io: %d, sw_data: %d\n", rec->sw_io,
75                    rec->sw_data);
76         snd_printk(KERN_DEBUG "STAT: byte_sizes[]:\n");
77         k = 0;
78         for (j = 0; j < 8; j++) {
79                 for (i = j * 8; i < (j + 1) * 8; i++)
80                         if (rec->byte_sizes[i] != 0) {
81                                 snd_printk(KERN_DEBUG "%u: %u",
82                                            i, rec->byte_sizes[i]);
83                                 k++;
84                         }
85                 if (((k % 8) == 0) && (k != 0)) {
86                         snd_printk(KERN_DEBUG "\n");
87                         k = 0;
88                 }
89         }
90         snd_printk(KERN_DEBUG "\n");
91         snd_printk(KERN_DEBUG "STAT: zero_sizes[]:\n");
92         for (j = 0; j < 8; j++) {
93                 k = 0;
94                 for (i = j * 8; i < (j + 1) * 8; i++)
95                         if (rec->zero_sizes[i] != 0)
96                                 snd_printk(KERN_DEBUG "%u: %u",
97                                            i, rec->zero_sizes[i]);
98                         else
99                                 k++;
100                 if (!k)
101                         snd_printk(KERN_DEBUG "\n");
102         }
103         snd_printk(KERN_DEBUG "\n");
104         snd_printk(KERN_DEBUG "STAT: min_adds[]:\n");
105         for (j = 0; j < 8; j++) {
106                 if (rec->min_adds[j] != 0)
107                         snd_printk(KERN_DEBUG "%u: %u", j, rec->min_adds[j]);
108         }
109         snd_printk(KERN_DEBUG "\n");
110         snd_printk(KERN_DEBUG "STAT: mul_adds[]:\n");
111         for (j = 0; j < 8; j++) {
112                 if (rec->mul_adds[j] != 0)
113                         snd_printk(KERN_DEBUG "%u: %u", j, rec->mul_adds[j]);
114         }
115         snd_printk(KERN_DEBUG "\n");
116         snd_printk(KERN_DEBUG
117                    "STAT: zero_times_saved: %d, zero_times_notsaved: %d\n",
118                    rec->zero_times_saved, rec->zero_times_notsaved);
119         /* snd_printk(KERN_DEBUG "STAT: zero_times[]\n");
120         i = 0;
121         for (j = 0; j < 3750; j++) {
122                 if (rec->zero_times[j] != 0) {
123                         snd_printk(KERN_DEBUG "%u: %u", j, rec->zero_times[j]);
124                         i++;
125                 }
126                 if (((i % 8) == 0) && (i != 0))
127                         snd_printk(KERN_DEBUG "\n");
128         }
129         snd_printk(KERN_DEBUG "\n"); */
130         return;
131 }
132 #endif
133
134 /*
135  * _internal_ helper function for playback/capture transfer function
136  */
137 static void
138 snd_pcm_indirect2_increase_min_periods(struct snd_pcm_substream *substream,
139                                        struct snd_pcm_indirect2 *rec,
140                                        int isplay, int iscopy,
141                                        unsigned int bytes)
142 {
143         if (rec->min_periods >= 0) {
144                 if (iscopy) {
145                         rec->sw_io += bytes;
146                         if (rec->sw_io >= rec->sw_buffer_size)
147                                 rec->sw_io -= rec->sw_buffer_size;
148                 } else if (isplay) {
149                         /* If application does not write data in multiples of
150                          * a period, move sw_data to the next correctly aligned
151                          * position, so that sw_io can converge to it (in the
152                          * next step).
153                          */
154                         if (!rec->check_alignment) {
155                                 if (rec->bytes2hw %
156                                     snd_pcm_lib_period_bytes(substream)) {
157                                         unsigned bytes2hw_aligned =
158                                             (1 +
159                                              (rec->bytes2hw /
160                                               snd_pcm_lib_period_bytes
161                                               (substream))) *
162                                             snd_pcm_lib_period_bytes
163                                             (substream);
164                                         rec->sw_data =
165                                             bytes2hw_aligned %
166                                             rec->sw_buffer_size;
167 #ifdef SND_PCM_INDIRECT2_STAT
168                                         snd_printk(KERN_DEBUG
169                                                    "STAT: @re-align: aligned "
170                                                    "bytes2hw to next period "
171                                                    "size boundary: %d "
172                                                    "(instead of %d)\n",
173                                                    bytes2hw_aligned,
174                                                    rec->bytes2hw);
175                                         snd_printk(KERN_DEBUG
176                                                    "STAT: @re-align: sw_data "
177                                                    "moves to: %d\n",
178                                                    rec->sw_data);
179 #endif
180                                 }
181                                 rec->check_alignment = 1;
182                         }
183                         /* We are at the end and are copying zeros into the
184                          * fifo.
185                          * Now, we have to make sure that sw_io is increased
186                          * until the position of sw_data: Filling the fifo with
187                          * the first zeros means, the last bytes were played.
188                          */
189                         if (rec->sw_io != rec->sw_data) {
190                                 unsigned int diff;
191                                 if (rec->sw_data > rec->sw_io)
192                                         diff = rec->sw_data - rec->sw_io;
193                                 else
194                                         diff = (rec->sw_buffer_size -
195                                                 rec->sw_io) +
196                                                 rec->sw_data;
197                                 if (bytes >= diff)
198                                         rec->sw_io = rec->sw_data;
199                                 else {
200                                         rec->sw_io += bytes;
201                                         if (rec->sw_io >= rec->sw_buffer_size)
202                                                 rec->sw_io -=
203                                                     rec->sw_buffer_size;
204                                 }
205                         }
206                 }
207                 rec->min_period_count += bytes;
208                 if (rec->min_period_count >= (rec->hw_buffer_size / 2)) {
209                         rec->min_periods += (rec->min_period_count /
210                                              (rec->hw_buffer_size / 2));
211 #ifdef SND_PCM_INDIRECT2_STAT
212                         if ((rec->min_period_count /
213                              (rec->hw_buffer_size / 2)) > 7)
214                                 snd_printk(KERN_DEBUG
215                                            "STAT: more than 7 (%d) min_adds "
216                                            "at once - too big to save!\n",
217                                            (rec->min_period_count /
218                                             (rec->hw_buffer_size / 2)));
219                         else
220                                 rec->min_adds[(rec->min_period_count /
221                                                (rec->hw_buffer_size / 2))]++;
222 #endif
223                         rec->min_period_count = (rec->min_period_count %
224                                                  (rec->hw_buffer_size / 2));
225                 }
226         } else if (isplay && iscopy)
227                 rec->min_periods = 0;
228 }
229
230 /*
231  * helper function for playback/capture pointer callback
232  */
233 snd_pcm_uframes_t
234 snd_pcm_indirect2_pointer(struct snd_pcm_substream *substream,
235                           struct snd_pcm_indirect2 *rec)
236 {
237 #ifdef SND_PCM_INDIRECT2_STAT
238         rec->pointer_calls++;
239 #endif
240         return bytes_to_frames(substream->runtime, rec->sw_io);
241 }
242
243 /*
244  * _internal_ helper function for playback interrupt callback
245  */
246 static void
247 snd_pcm_indirect2_playback_transfer(struct snd_pcm_substream *substream,
248                                     struct snd_pcm_indirect2 *rec,
249                                     snd_pcm_indirect2_copy_t copy,
250                                     snd_pcm_indirect2_zero_t zero)
251 {
252         struct snd_pcm_runtime *runtime = substream->runtime;
253         snd_pcm_uframes_t appl_ptr = runtime->control->appl_ptr;
254
255         /* runtime->control->appl_ptr: position where ALSA will write next time
256          * rec->appl_ptr: position where ALSA was last time
257          * diff: obviously ALSA wrote that much bytes into the intermediate
258          * buffer since we checked last time
259          */
260         snd_pcm_sframes_t diff = appl_ptr - rec->appl_ptr;
261
262         if (diff) {
263 #ifdef SND_PCM_INDIRECT2_STAT
264                 rec->lastdifftime = jiffies;
265 #endif
266                 if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
267                         diff += runtime->boundary;
268                 /* number of bytes "added" by ALSA increases the number of
269                  * bytes which are ready to "be transfered to HW"/"played"
270                  * Then, set rec->appl_ptr to not count bytes twice next time.
271                  */
272                 rec->sw_ready += (int)frames_to_bytes(runtime, diff);
273                 rec->appl_ptr = appl_ptr;
274         }
275         if (rec->hw_ready && (rec->sw_ready <= 0)) {
276                 unsigned int bytes;
277
278 #ifdef SND_PCM_INDIRECT2_STAT
279                 if (rec->firstzerotime == 0) {
280                         rec->firstzerotime = jiffies;
281                         snd_printk(KERN_DEBUG
282                                    "STAT: @firstzerotime: mul_elapsed: %d, "
283                                    "min_period_count: %d\n",
284                                    rec->mul_elapsed, rec->min_period_count);
285                         snd_printk(KERN_DEBUG
286                                    "STAT: @firstzerotime: sw_io: %d, "
287                                    "sw_data: %d, appl_ptr: %u\n",
288                                    rec->sw_io, rec->sw_data,
289                                    (unsigned int)appl_ptr);
290                 }
291                 if ((jiffies - rec->firstzerotime) < 3750) {
292                         rec->zero_times[(jiffies - rec->firstzerotime)]++;
293                         rec->zero_times_saved++;
294                 } else
295                         rec->zero_times_notsaved++;
296 #endif
297                 bytes = zero(substream, rec);
298
299 #ifdef SND_PCM_INDIRECT2_STAT
300                 rec->zeros2hw += bytes;
301                 if (bytes < 64)
302                         rec->zero_sizes[bytes]++;
303                 else
304                         snd_printk(KERN_DEBUG
305                                    "STAT: %d zero Bytes copied to hardware at "
306                                    "once - too big to save!\n",
307                                    bytes);
308 #endif
309                 snd_pcm_indirect2_increase_min_periods(substream, rec, 1, 0,
310                                                        bytes);
311                 return;
312         }
313         while (rec->hw_ready && (rec->sw_ready > 0)) {
314                 /* sw_to_end: max. number of bytes that can be read/take from
315                  * the current position (sw_data) in _one_ step
316                  */
317                 unsigned int sw_to_end = rec->sw_buffer_size - rec->sw_data;
318
319                 /* bytes: number of bytes we have available (for reading) */
320                 unsigned int bytes = rec->sw_ready;
321
322                 if (sw_to_end < bytes)
323                         bytes = sw_to_end;
324                 if (!bytes)
325                         break;
326
327 #ifdef SND_PCM_INDIRECT2_STAT
328                 if (rec->firstbytetime == 0)
329                         rec->firstbytetime = jiffies;
330                 rec->lastbytetime = jiffies;
331 #endif
332                 /* copy bytes from intermediate buffer position sw_data to the
333                  * HW and return number of bytes actually written
334                  * Furthermore, set hw_ready to 0, if the fifo isn't empty
335                  * now => more could be transfered to fifo
336                  */
337                 bytes = copy(substream, rec, bytes);
338                 rec->bytes2hw += bytes;
339
340 #ifdef SND_PCM_INDIRECT2_STAT
341                 if (bytes < 64)
342                         rec->byte_sizes[bytes]++;
343                 else
344                         snd_printk(KERN_DEBUG
345                                    "STAT: %d Bytes copied to hardware at once "
346                                    "- too big to save!\n",
347                                    bytes);
348 #endif
349                 /* increase sw_data by the number of actually written bytes
350                  * (= number of taken bytes from intermediate buffer)
351                  */
352                 rec->sw_data += bytes;
353                 if (rec->sw_data == rec->sw_buffer_size)
354                         rec->sw_data = 0;
355                 /* now sw_data is the position where ALSA is going to write
356                  * in the intermediate buffer next time = position we are going
357                  * to read from next time
358                  */
359
360                 snd_pcm_indirect2_increase_min_periods(substream, rec, 1, 1,
361                                                        bytes);
362
363                 /* we read bytes from intermediate buffer, so we need to say
364                  * that the number of bytes ready for transfer are decreased
365                  * now
366                  */
367                 rec->sw_ready -= bytes;
368         }
369         return;
370 }
371
372 /*
373  * helper function for playback interrupt routine
374  */
375 void
376 snd_pcm_indirect2_playback_interrupt(struct snd_pcm_substream *substream,
377                                      struct snd_pcm_indirect2 *rec,
378                                      snd_pcm_indirect2_copy_t copy,
379                                      snd_pcm_indirect2_zero_t zero)
380 {
381 #ifdef SND_PCM_INDIRECT2_STAT
382         rec->irq_occured++;
383 #endif
384         /* hardware played some bytes, so there is room again (in fifo) */
385         rec->hw_ready = 1;
386
387         /* don't call ack() now, instead call transfer() function directly
388          * (normally called by ack() )
389          */
390         snd_pcm_indirect2_playback_transfer(substream, rec, copy, zero);
391
392         if (rec->min_periods >= rec->min_multiple) {
393 #ifdef SND_PCM_INDIRECT2_STAT
394                 if ((rec->min_periods / rec->min_multiple) > 7)
395                         snd_printk(KERN_DEBUG
396                                    "STAT: more than 7 (%d) mul_adds - too big "
397                                    "to save!\n",
398                                    (rec->min_periods / rec->min_multiple));
399                 else
400                         rec->mul_adds[(rec->min_periods /
401                                        rec->min_multiple)]++;
402                 rec->mul_elapsed_real += (rec->min_periods /
403                                           rec->min_multiple);
404                 rec->mul_elapsed++;
405 #endif
406                 rec->min_periods = (rec->min_periods % rec->min_multiple);
407                 snd_pcm_period_elapsed(substream);
408         }
409 }
410
411 /*
412  * _internal_ helper function for capture interrupt callback
413  */
414 static void
415 snd_pcm_indirect2_capture_transfer(struct snd_pcm_substream *substream,
416                                    struct snd_pcm_indirect2 *rec,
417                                    snd_pcm_indirect2_copy_t copy,
418                                    snd_pcm_indirect2_zero_t null)
419 {
420         struct snd_pcm_runtime *runtime = substream->runtime;
421         snd_pcm_uframes_t appl_ptr = runtime->control->appl_ptr;
422         snd_pcm_sframes_t diff = appl_ptr - rec->appl_ptr;
423
424         if (diff) {
425 #ifdef SND_PCM_INDIRECT2_STAT
426                 rec->lastdifftime = jiffies;
427 #endif
428                 if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
429                         diff += runtime->boundary;
430                 rec->sw_ready -= frames_to_bytes(runtime, diff);
431                 rec->appl_ptr = appl_ptr;
432         }
433         /* if hardware has something, but the intermediate buffer is full
434          * => skip contents of buffer
435          */
436         if (rec->hw_ready && (rec->sw_ready >= (int)rec->sw_buffer_size)) {
437                 unsigned int bytes;
438
439 #ifdef SND_PCM_INDIRECT2_STAT
440                 if (rec->firstzerotime == 0) {
441                         rec->firstzerotime = jiffies;
442                         snd_printk(KERN_DEBUG "STAT: (capture) "
443                                    "@firstzerotime: mul_elapsed: %d, "
444                                    "min_period_count: %d\n",
445                                    rec->mul_elapsed, rec->min_period_count);
446                         snd_printk(KERN_DEBUG "STAT: (capture) "
447                                    "@firstzerotime: sw_io: %d, sw_data: %d, "
448                                    "appl_ptr: %u\n",
449                                    rec->sw_io, rec->sw_data,
450                                    (unsigned int)appl_ptr);
451                 }
452                 if ((jiffies - rec->firstzerotime) < 3750) {
453                         rec->zero_times[(jiffies - rec->firstzerotime)]++;
454                         rec->zero_times_saved++;
455                 } else
456                         rec->zero_times_notsaved++;
457 #endif
458                 bytes = null(substream, rec);
459
460 #ifdef SND_PCM_INDIRECT2_STAT
461                 rec->zeros2hw += bytes;
462                 if (bytes < 64)
463                         rec->zero_sizes[bytes]++;
464                 else
465                         snd_printk(KERN_DEBUG
466                                    "STAT: (capture) %d zero Bytes copied to "
467                                    "hardware at once - too big to save!\n",
468                                    bytes);
469 #endif
470                 snd_pcm_indirect2_increase_min_periods(substream, rec, 0, 0,
471                                                        bytes);
472                 /* report an overrun */
473                 rec->sw_io = SNDRV_PCM_POS_XRUN;
474                 return;
475         }
476         while (rec->hw_ready && (rec->sw_ready < (int)rec->sw_buffer_size)) {
477                 /* sw_to_end: max. number of bytes that we can write to the
478                  *  intermediate buffer (until it's end)
479                  */
480                 size_t sw_to_end = rec->sw_buffer_size - rec->sw_data;
481
482                 /* bytes: max. number of bytes, which may be copied to the
483                  *  intermediate buffer without overflow (in _one_ step)
484                  */
485                 size_t bytes = rec->sw_buffer_size - rec->sw_ready;
486
487                 /* limit number of bytes (for transfer) by available room in
488                  * the intermediate buffer
489                  */
490                 if (sw_to_end < bytes)
491                         bytes = sw_to_end;
492                 if (!bytes)
493                         break;
494
495 #ifdef SND_PCM_INDIRECT2_STAT
496                 if (rec->firstbytetime == 0)
497                         rec->firstbytetime = jiffies;
498                 rec->lastbytetime = jiffies;
499 #endif
500                 /* copy bytes from the intermediate buffer (position sw_data)
501                  * to the HW at most and return number of bytes actually copied
502                  * from HW
503                  * Furthermore, set hw_ready to 0, if the fifo is empty now.
504                  */
505                 bytes = copy(substream, rec, bytes);
506                 rec->bytes2hw += bytes;
507
508 #ifdef SND_PCM_INDIRECT2_STAT
509                 if (bytes < 64)
510                         rec->byte_sizes[bytes]++;
511                 else
512                         snd_printk(KERN_DEBUG
513                                    "STAT: (capture) %d Bytes copied to "
514                                    "hardware at once - too big to save!\n",
515                                    bytes);
516 #endif
517                 /* increase sw_data by the number of actually copied bytes from
518                  * HW
519                  */
520                 rec->sw_data += bytes;
521                 if (rec->sw_data == rec->sw_buffer_size)
522                         rec->sw_data = 0;
523
524                 snd_pcm_indirect2_increase_min_periods(substream, rec, 0, 1,
525                                                        bytes);
526
527                 /* number of bytes in the intermediate buffer, which haven't
528                  * been fetched by ALSA yet.
529                  */
530                 rec->sw_ready += bytes;
531         }
532         return;
533 }
534
535 /*
536  * helper function for capture interrupt routine
537  */
538 void
539 snd_pcm_indirect2_capture_interrupt(struct snd_pcm_substream *substream,
540                                     struct snd_pcm_indirect2 *rec,
541                                     snd_pcm_indirect2_copy_t copy,
542                                     snd_pcm_indirect2_zero_t null)
543 {
544 #ifdef SND_PCM_INDIRECT2_STAT
545         rec->irq_occured++;
546 #endif
547         /* hardware recorded some bytes, so there is something to read from the
548          * record fifo:
549          */
550         rec->hw_ready = 1;
551
552         /* don't call ack() now, instead call transfer() function directly
553          * (normally called by ack() )
554          */
555         snd_pcm_indirect2_capture_transfer(substream, rec, copy, null);
556
557         if (rec->min_periods >= rec->min_multiple) {
558
559 #ifdef SND_PCM_INDIRECT2_STAT
560                 if ((rec->min_periods / rec->min_multiple) > 7)
561                         snd_printk(KERN_DEBUG
562                                    "STAT: more than 7 (%d) mul_adds - "
563                                    "too big to save!\n",
564                                    (rec->min_periods / rec->min_multiple));
565                 else
566                         rec->mul_adds[(rec->min_periods /
567                                        rec->min_multiple)]++;
568                 rec->mul_elapsed_real += (rec->min_periods /
569                                           rec->min_multiple);
570                 rec->mul_elapsed++;
571 #endif
572                 rec->min_periods = (rec->min_periods % rec->min_multiple);
573                 snd_pcm_period_elapsed(substream);
574         }
575 }