treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
[sfrench/cifs-2.6.git] / sound / drivers / dummy.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Dummy soundcard
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  */
6
7 #include <linux/init.h>
8 #include <linux/err.h>
9 #include <linux/platform_device.h>
10 #include <linux/jiffies.h>
11 #include <linux/slab.h>
12 #include <linux/time.h>
13 #include <linux/wait.h>
14 #include <linux/hrtimer.h>
15 #include <linux/math64.h>
16 #include <linux/module.h>
17 #include <sound/core.h>
18 #include <sound/control.h>
19 #include <sound/tlv.h>
20 #include <sound/pcm.h>
21 #include <sound/rawmidi.h>
22 #include <sound/info.h>
23 #include <sound/initval.h>
24
25 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
26 MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
27 MODULE_LICENSE("GPL");
28 MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");
29
30 #define MAX_PCM_DEVICES         4
31 #define MAX_PCM_SUBSTREAMS      128
32 #define MAX_MIDI_DEVICES        2
33
34 /* defaults */
35 #define MAX_BUFFER_SIZE         (64*1024)
36 #define MIN_PERIOD_SIZE         64
37 #define MAX_PERIOD_SIZE         MAX_BUFFER_SIZE
38 #define USE_FORMATS             (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
39 #define USE_RATE                SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
40 #define USE_RATE_MIN            5500
41 #define USE_RATE_MAX            48000
42 #define USE_CHANNELS_MIN        1
43 #define USE_CHANNELS_MAX        2
44 #define USE_PERIODS_MIN         1
45 #define USE_PERIODS_MAX         1024
46
47 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
48 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
49 static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
50 static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
51 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
52 static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
53 //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
54 #ifdef CONFIG_HIGH_RES_TIMERS
55 static bool hrtimer = 1;
56 #endif
57 static bool fake_buffer = 1;
58
59 module_param_array(index, int, NULL, 0444);
60 MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
61 module_param_array(id, charp, NULL, 0444);
62 MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
63 module_param_array(enable, bool, NULL, 0444);
64 MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
65 module_param_array(model, charp, NULL, 0444);
66 MODULE_PARM_DESC(model, "Soundcard model.");
67 module_param_array(pcm_devs, int, NULL, 0444);
68 MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
69 module_param_array(pcm_substreams, int, NULL, 0444);
70 MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-128) for dummy driver.");
71 //module_param_array(midi_devs, int, NULL, 0444);
72 //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
73 module_param(fake_buffer, bool, 0444);
74 MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
75 #ifdef CONFIG_HIGH_RES_TIMERS
76 module_param(hrtimer, bool, 0644);
77 MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
78 #endif
79
80 static struct platform_device *devices[SNDRV_CARDS];
81
82 #define MIXER_ADDR_MASTER       0
83 #define MIXER_ADDR_LINE         1
84 #define MIXER_ADDR_MIC          2
85 #define MIXER_ADDR_SYNTH        3
86 #define MIXER_ADDR_CD           4
87 #define MIXER_ADDR_LAST         4
88
89 struct dummy_timer_ops {
90         int (*create)(struct snd_pcm_substream *);
91         void (*free)(struct snd_pcm_substream *);
92         int (*prepare)(struct snd_pcm_substream *);
93         int (*start)(struct snd_pcm_substream *);
94         int (*stop)(struct snd_pcm_substream *);
95         snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
96 };
97
98 #define get_dummy_ops(substream) \
99         (*(const struct dummy_timer_ops **)(substream)->runtime->private_data)
100
101 struct dummy_model {
102         const char *name;
103         int (*playback_constraints)(struct snd_pcm_runtime *runtime);
104         int (*capture_constraints)(struct snd_pcm_runtime *runtime);
105         u64 formats;
106         size_t buffer_bytes_max;
107         size_t period_bytes_min;
108         size_t period_bytes_max;
109         unsigned int periods_min;
110         unsigned int periods_max;
111         unsigned int rates;
112         unsigned int rate_min;
113         unsigned int rate_max;
114         unsigned int channels_min;
115         unsigned int channels_max;
116 };
117
118 struct snd_dummy {
119         struct snd_card *card;
120         struct dummy_model *model;
121         struct snd_pcm *pcm;
122         struct snd_pcm_hardware pcm_hw;
123         spinlock_t mixer_lock;
124         int mixer_volume[MIXER_ADDR_LAST+1][2];
125         int capture_source[MIXER_ADDR_LAST+1][2];
126         int iobox;
127         struct snd_kcontrol *cd_volume_ctl;
128         struct snd_kcontrol *cd_switch_ctl;
129 };
130
131 /*
132  * card models
133  */
134
135 static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
136 {
137         int err;
138         err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
139         if (err < 0)
140                 return err;
141         err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
142         if (err < 0)
143                 return err;
144         return 0;
145 }
146
147 static struct dummy_model model_emu10k1 = {
148         .name = "emu10k1",
149         .playback_constraints = emu10k1_playback_constraints,
150         .buffer_bytes_max = 128 * 1024,
151 };
152
153 static struct dummy_model model_rme9652 = {
154         .name = "rme9652",
155         .buffer_bytes_max = 26 * 64 * 1024,
156         .formats = SNDRV_PCM_FMTBIT_S32_LE,
157         .channels_min = 26,
158         .channels_max = 26,
159         .periods_min = 2,
160         .periods_max = 2,
161 };
162
163 static struct dummy_model model_ice1712 = {
164         .name = "ice1712",
165         .buffer_bytes_max = 256 * 1024,
166         .formats = SNDRV_PCM_FMTBIT_S32_LE,
167         .channels_min = 10,
168         .channels_max = 10,
169         .periods_min = 1,
170         .periods_max = 1024,
171 };
172
173 static struct dummy_model model_uda1341 = {
174         .name = "uda1341",
175         .buffer_bytes_max = 16380,
176         .formats = SNDRV_PCM_FMTBIT_S16_LE,
177         .channels_min = 2,
178         .channels_max = 2,
179         .periods_min = 2,
180         .periods_max = 255,
181 };
182
183 static struct dummy_model model_ac97 = {
184         .name = "ac97",
185         .formats = SNDRV_PCM_FMTBIT_S16_LE,
186         .channels_min = 2,
187         .channels_max = 2,
188         .rates = SNDRV_PCM_RATE_48000,
189         .rate_min = 48000,
190         .rate_max = 48000,
191 };
192
193 static struct dummy_model model_ca0106 = {
194         .name = "ca0106",
195         .formats = SNDRV_PCM_FMTBIT_S16_LE,
196         .buffer_bytes_max = ((65536-64)*8),
197         .period_bytes_max = (65536-64),
198         .periods_min = 2,
199         .periods_max = 8,
200         .channels_min = 2,
201         .channels_max = 2,
202         .rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
203         .rate_min = 48000,
204         .rate_max = 192000,
205 };
206
207 static struct dummy_model *dummy_models[] = {
208         &model_emu10k1,
209         &model_rme9652,
210         &model_ice1712,
211         &model_uda1341,
212         &model_ac97,
213         &model_ca0106,
214         NULL
215 };
216
217 /*
218  * system timer interface
219  */
220
221 struct dummy_systimer_pcm {
222         /* ops must be the first item */
223         const struct dummy_timer_ops *timer_ops;
224         spinlock_t lock;
225         struct timer_list timer;
226         unsigned long base_time;
227         unsigned int frac_pos;  /* fractional sample position (based HZ) */
228         unsigned int frac_period_rest;
229         unsigned int frac_buffer_size;  /* buffer_size * HZ */
230         unsigned int frac_period_size;  /* period_size * HZ */
231         unsigned int rate;
232         int elapsed;
233         struct snd_pcm_substream *substream;
234 };
235
236 static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
237 {
238         mod_timer(&dpcm->timer, jiffies +
239                 (dpcm->frac_period_rest + dpcm->rate - 1) / dpcm->rate);
240 }
241
242 static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
243 {
244         unsigned long delta;
245
246         delta = jiffies - dpcm->base_time;
247         if (!delta)
248                 return;
249         dpcm->base_time += delta;
250         delta *= dpcm->rate;
251         dpcm->frac_pos += delta;
252         while (dpcm->frac_pos >= dpcm->frac_buffer_size)
253                 dpcm->frac_pos -= dpcm->frac_buffer_size;
254         while (dpcm->frac_period_rest <= delta) {
255                 dpcm->elapsed++;
256                 dpcm->frac_period_rest += dpcm->frac_period_size;
257         }
258         dpcm->frac_period_rest -= delta;
259 }
260
261 static int dummy_systimer_start(struct snd_pcm_substream *substream)
262 {
263         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
264         spin_lock(&dpcm->lock);
265         dpcm->base_time = jiffies;
266         dummy_systimer_rearm(dpcm);
267         spin_unlock(&dpcm->lock);
268         return 0;
269 }
270
271 static int dummy_systimer_stop(struct snd_pcm_substream *substream)
272 {
273         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
274         spin_lock(&dpcm->lock);
275         del_timer(&dpcm->timer);
276         spin_unlock(&dpcm->lock);
277         return 0;
278 }
279
280 static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
281 {
282         struct snd_pcm_runtime *runtime = substream->runtime;
283         struct dummy_systimer_pcm *dpcm = runtime->private_data;
284
285         dpcm->frac_pos = 0;
286         dpcm->rate = runtime->rate;
287         dpcm->frac_buffer_size = runtime->buffer_size * HZ;
288         dpcm->frac_period_size = runtime->period_size * HZ;
289         dpcm->frac_period_rest = dpcm->frac_period_size;
290         dpcm->elapsed = 0;
291
292         return 0;
293 }
294
295 static void dummy_systimer_callback(struct timer_list *t)
296 {
297         struct dummy_systimer_pcm *dpcm = from_timer(dpcm, t, timer);
298         unsigned long flags;
299         int elapsed = 0;
300         
301         spin_lock_irqsave(&dpcm->lock, flags);
302         dummy_systimer_update(dpcm);
303         dummy_systimer_rearm(dpcm);
304         elapsed = dpcm->elapsed;
305         dpcm->elapsed = 0;
306         spin_unlock_irqrestore(&dpcm->lock, flags);
307         if (elapsed)
308                 snd_pcm_period_elapsed(dpcm->substream);
309 }
310
311 static snd_pcm_uframes_t
312 dummy_systimer_pointer(struct snd_pcm_substream *substream)
313 {
314         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
315         snd_pcm_uframes_t pos;
316
317         spin_lock(&dpcm->lock);
318         dummy_systimer_update(dpcm);
319         pos = dpcm->frac_pos / HZ;
320         spin_unlock(&dpcm->lock);
321         return pos;
322 }
323
324 static int dummy_systimer_create(struct snd_pcm_substream *substream)
325 {
326         struct dummy_systimer_pcm *dpcm;
327
328         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
329         if (!dpcm)
330                 return -ENOMEM;
331         substream->runtime->private_data = dpcm;
332         timer_setup(&dpcm->timer, dummy_systimer_callback, 0);
333         spin_lock_init(&dpcm->lock);
334         dpcm->substream = substream;
335         return 0;
336 }
337
338 static void dummy_systimer_free(struct snd_pcm_substream *substream)
339 {
340         kfree(substream->runtime->private_data);
341 }
342
343 static const struct dummy_timer_ops dummy_systimer_ops = {
344         .create =       dummy_systimer_create,
345         .free =         dummy_systimer_free,
346         .prepare =      dummy_systimer_prepare,
347         .start =        dummy_systimer_start,
348         .stop =         dummy_systimer_stop,
349         .pointer =      dummy_systimer_pointer,
350 };
351
352 #ifdef CONFIG_HIGH_RES_TIMERS
353 /*
354  * hrtimer interface
355  */
356
357 struct dummy_hrtimer_pcm {
358         /* ops must be the first item */
359         const struct dummy_timer_ops *timer_ops;
360         ktime_t base_time;
361         ktime_t period_time;
362         atomic_t running;
363         struct hrtimer timer;
364         struct snd_pcm_substream *substream;
365 };
366
367 static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
368 {
369         struct dummy_hrtimer_pcm *dpcm;
370
371         dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
372         if (!atomic_read(&dpcm->running))
373                 return HRTIMER_NORESTART;
374         /*
375          * In cases of XRUN and draining, this calls .trigger to stop PCM
376          * substream.
377          */
378         snd_pcm_period_elapsed(dpcm->substream);
379         if (!atomic_read(&dpcm->running))
380                 return HRTIMER_NORESTART;
381
382         hrtimer_forward_now(timer, dpcm->period_time);
383         return HRTIMER_RESTART;
384 }
385
386 static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
387 {
388         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
389
390         dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
391         hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL_SOFT);
392         atomic_set(&dpcm->running, 1);
393         return 0;
394 }
395
396 static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
397 {
398         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
399
400         atomic_set(&dpcm->running, 0);
401         if (!hrtimer_callback_running(&dpcm->timer))
402                 hrtimer_cancel(&dpcm->timer);
403         return 0;
404 }
405
406 static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
407 {
408         hrtimer_cancel(&dpcm->timer);
409 }
410
411 static snd_pcm_uframes_t
412 dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
413 {
414         struct snd_pcm_runtime *runtime = substream->runtime;
415         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
416         u64 delta;
417         u32 pos;
418
419         delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
420                                dpcm->base_time);
421         delta = div_u64(delta * runtime->rate + 999999, 1000000);
422         div_u64_rem(delta, runtime->buffer_size, &pos);
423         return pos;
424 }
425
426 static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
427 {
428         struct snd_pcm_runtime *runtime = substream->runtime;
429         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
430         unsigned int period, rate;
431         long sec;
432         unsigned long nsecs;
433
434         dummy_hrtimer_sync(dpcm);
435         period = runtime->period_size;
436         rate = runtime->rate;
437         sec = period / rate;
438         period %= rate;
439         nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
440         dpcm->period_time = ktime_set(sec, nsecs);
441
442         return 0;
443 }
444
445 static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
446 {
447         struct dummy_hrtimer_pcm *dpcm;
448
449         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
450         if (!dpcm)
451                 return -ENOMEM;
452         substream->runtime->private_data = dpcm;
453         hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
454         dpcm->timer.function = dummy_hrtimer_callback;
455         dpcm->substream = substream;
456         atomic_set(&dpcm->running, 0);
457         return 0;
458 }
459
460 static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
461 {
462         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
463         dummy_hrtimer_sync(dpcm);
464         kfree(dpcm);
465 }
466
467 static const struct dummy_timer_ops dummy_hrtimer_ops = {
468         .create =       dummy_hrtimer_create,
469         .free =         dummy_hrtimer_free,
470         .prepare =      dummy_hrtimer_prepare,
471         .start =        dummy_hrtimer_start,
472         .stop =         dummy_hrtimer_stop,
473         .pointer =      dummy_hrtimer_pointer,
474 };
475
476 #endif /* CONFIG_HIGH_RES_TIMERS */
477
478 /*
479  * PCM interface
480  */
481
482 static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
483 {
484         switch (cmd) {
485         case SNDRV_PCM_TRIGGER_START:
486         case SNDRV_PCM_TRIGGER_RESUME:
487                 return get_dummy_ops(substream)->start(substream);
488         case SNDRV_PCM_TRIGGER_STOP:
489         case SNDRV_PCM_TRIGGER_SUSPEND:
490                 return get_dummy_ops(substream)->stop(substream);
491         }
492         return -EINVAL;
493 }
494
495 static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
496 {
497         return get_dummy_ops(substream)->prepare(substream);
498 }
499
500 static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
501 {
502         return get_dummy_ops(substream)->pointer(substream);
503 }
504
505 static const struct snd_pcm_hardware dummy_pcm_hardware = {
506         .info =                 (SNDRV_PCM_INFO_MMAP |
507                                  SNDRV_PCM_INFO_INTERLEAVED |
508                                  SNDRV_PCM_INFO_RESUME |
509                                  SNDRV_PCM_INFO_MMAP_VALID),
510         .formats =              USE_FORMATS,
511         .rates =                USE_RATE,
512         .rate_min =             USE_RATE_MIN,
513         .rate_max =             USE_RATE_MAX,
514         .channels_min =         USE_CHANNELS_MIN,
515         .channels_max =         USE_CHANNELS_MAX,
516         .buffer_bytes_max =     MAX_BUFFER_SIZE,
517         .period_bytes_min =     MIN_PERIOD_SIZE,
518         .period_bytes_max =     MAX_PERIOD_SIZE,
519         .periods_min =          USE_PERIODS_MIN,
520         .periods_max =          USE_PERIODS_MAX,
521         .fifo_size =            0,
522 };
523
524 static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
525                                struct snd_pcm_hw_params *hw_params)
526 {
527         if (fake_buffer) {
528                 /* runtime->dma_bytes has to be set manually to allow mmap */
529                 substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
530                 return 0;
531         }
532         return snd_pcm_lib_malloc_pages(substream,
533                                         params_buffer_bytes(hw_params));
534 }
535
536 static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
537 {
538         if (fake_buffer)
539                 return 0;
540         return snd_pcm_lib_free_pages(substream);
541 }
542
543 static int dummy_pcm_open(struct snd_pcm_substream *substream)
544 {
545         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
546         struct dummy_model *model = dummy->model;
547         struct snd_pcm_runtime *runtime = substream->runtime;
548         const struct dummy_timer_ops *ops;
549         int err;
550
551         ops = &dummy_systimer_ops;
552 #ifdef CONFIG_HIGH_RES_TIMERS
553         if (hrtimer)
554                 ops = &dummy_hrtimer_ops;
555 #endif
556
557         err = ops->create(substream);
558         if (err < 0)
559                 return err;
560         get_dummy_ops(substream) = ops;
561
562         runtime->hw = dummy->pcm_hw;
563         if (substream->pcm->device & 1) {
564                 runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
565                 runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
566         }
567         if (substream->pcm->device & 2)
568                 runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
569                                       SNDRV_PCM_INFO_MMAP_VALID);
570
571         if (model == NULL)
572                 return 0;
573
574         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
575                 if (model->playback_constraints)
576                         err = model->playback_constraints(substream->runtime);
577         } else {
578                 if (model->capture_constraints)
579                         err = model->capture_constraints(substream->runtime);
580         }
581         if (err < 0) {
582                 get_dummy_ops(substream)->free(substream);
583                 return err;
584         }
585         return 0;
586 }
587
588 static int dummy_pcm_close(struct snd_pcm_substream *substream)
589 {
590         get_dummy_ops(substream)->free(substream);
591         return 0;
592 }
593
594 /*
595  * dummy buffer handling
596  */
597
598 static void *dummy_page[2];
599
600 static void free_fake_buffer(void)
601 {
602         if (fake_buffer) {
603                 int i;
604                 for (i = 0; i < 2; i++)
605                         if (dummy_page[i]) {
606                                 free_page((unsigned long)dummy_page[i]);
607                                 dummy_page[i] = NULL;
608                         }
609         }
610 }
611
612 static int alloc_fake_buffer(void)
613 {
614         int i;
615
616         if (!fake_buffer)
617                 return 0;
618         for (i = 0; i < 2; i++) {
619                 dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
620                 if (!dummy_page[i]) {
621                         free_fake_buffer();
622                         return -ENOMEM;
623                 }
624         }
625         return 0;
626 }
627
628 static int dummy_pcm_copy(struct snd_pcm_substream *substream,
629                           int channel, unsigned long pos,
630                           void __user *dst, unsigned long bytes)
631 {
632         return 0; /* do nothing */
633 }
634
635 static int dummy_pcm_copy_kernel(struct snd_pcm_substream *substream,
636                                  int channel, unsigned long pos,
637                                  void *dst, unsigned long bytes)
638 {
639         return 0; /* do nothing */
640 }
641
642 static int dummy_pcm_silence(struct snd_pcm_substream *substream,
643                              int channel, unsigned long pos,
644                              unsigned long bytes)
645 {
646         return 0; /* do nothing */
647 }
648
649 static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
650                                    unsigned long offset)
651 {
652         return virt_to_page(dummy_page[substream->stream]); /* the same page */
653 }
654
655 static struct snd_pcm_ops dummy_pcm_ops = {
656         .open =         dummy_pcm_open,
657         .close =        dummy_pcm_close,
658         .ioctl =        snd_pcm_lib_ioctl,
659         .hw_params =    dummy_pcm_hw_params,
660         .hw_free =      dummy_pcm_hw_free,
661         .prepare =      dummy_pcm_prepare,
662         .trigger =      dummy_pcm_trigger,
663         .pointer =      dummy_pcm_pointer,
664 };
665
666 static struct snd_pcm_ops dummy_pcm_ops_no_buf = {
667         .open =         dummy_pcm_open,
668         .close =        dummy_pcm_close,
669         .ioctl =        snd_pcm_lib_ioctl,
670         .hw_params =    dummy_pcm_hw_params,
671         .hw_free =      dummy_pcm_hw_free,
672         .prepare =      dummy_pcm_prepare,
673         .trigger =      dummy_pcm_trigger,
674         .pointer =      dummy_pcm_pointer,
675         .copy_user =    dummy_pcm_copy,
676         .copy_kernel =  dummy_pcm_copy_kernel,
677         .fill_silence = dummy_pcm_silence,
678         .page =         dummy_pcm_page,
679 };
680
681 static int snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
682                               int substreams)
683 {
684         struct snd_pcm *pcm;
685         struct snd_pcm_ops *ops;
686         int err;
687
688         err = snd_pcm_new(dummy->card, "Dummy PCM", device,
689                                substreams, substreams, &pcm);
690         if (err < 0)
691                 return err;
692         dummy->pcm = pcm;
693         if (fake_buffer)
694                 ops = &dummy_pcm_ops_no_buf;
695         else
696                 ops = &dummy_pcm_ops;
697         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
698         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
699         pcm->private_data = dummy;
700         pcm->info_flags = 0;
701         strcpy(pcm->name, "Dummy PCM");
702         if (!fake_buffer) {
703                 snd_pcm_lib_preallocate_pages_for_all(pcm,
704                         SNDRV_DMA_TYPE_CONTINUOUS,
705                         snd_dma_continuous_data(GFP_KERNEL),
706                         0, 64*1024);
707         }
708         return 0;
709 }
710
711 /*
712  * mixer interface
713  */
714
715 #define DUMMY_VOLUME(xname, xindex, addr) \
716 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
717   .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
718   .name = xname, .index = xindex, \
719   .info = snd_dummy_volume_info, \
720   .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
721   .private_value = addr, \
722   .tlv = { .p = db_scale_dummy } }
723
724 static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
725                                  struct snd_ctl_elem_info *uinfo)
726 {
727         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
728         uinfo->count = 2;
729         uinfo->value.integer.min = -50;
730         uinfo->value.integer.max = 100;
731         return 0;
732 }
733  
734 static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
735                                 struct snd_ctl_elem_value *ucontrol)
736 {
737         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
738         int addr = kcontrol->private_value;
739
740         spin_lock_irq(&dummy->mixer_lock);
741         ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
742         ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
743         spin_unlock_irq(&dummy->mixer_lock);
744         return 0;
745 }
746
747 static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
748                                 struct snd_ctl_elem_value *ucontrol)
749 {
750         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
751         int change, addr = kcontrol->private_value;
752         int left, right;
753
754         left = ucontrol->value.integer.value[0];
755         if (left < -50)
756                 left = -50;
757         if (left > 100)
758                 left = 100;
759         right = ucontrol->value.integer.value[1];
760         if (right < -50)
761                 right = -50;
762         if (right > 100)
763                 right = 100;
764         spin_lock_irq(&dummy->mixer_lock);
765         change = dummy->mixer_volume[addr][0] != left ||
766                  dummy->mixer_volume[addr][1] != right;
767         dummy->mixer_volume[addr][0] = left;
768         dummy->mixer_volume[addr][1] = right;
769         spin_unlock_irq(&dummy->mixer_lock);
770         return change;
771 }
772
773 static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
774
775 #define DUMMY_CAPSRC(xname, xindex, addr) \
776 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
777   .info = snd_dummy_capsrc_info, \
778   .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
779   .private_value = addr }
780
781 #define snd_dummy_capsrc_info   snd_ctl_boolean_stereo_info
782  
783 static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
784                                 struct snd_ctl_elem_value *ucontrol)
785 {
786         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
787         int addr = kcontrol->private_value;
788
789         spin_lock_irq(&dummy->mixer_lock);
790         ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
791         ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
792         spin_unlock_irq(&dummy->mixer_lock);
793         return 0;
794 }
795
796 static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
797 {
798         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
799         int change, addr = kcontrol->private_value;
800         int left, right;
801
802         left = ucontrol->value.integer.value[0] & 1;
803         right = ucontrol->value.integer.value[1] & 1;
804         spin_lock_irq(&dummy->mixer_lock);
805         change = dummy->capture_source[addr][0] != left &&
806                  dummy->capture_source[addr][1] != right;
807         dummy->capture_source[addr][0] = left;
808         dummy->capture_source[addr][1] = right;
809         spin_unlock_irq(&dummy->mixer_lock);
810         return change;
811 }
812
813 static int snd_dummy_iobox_info(struct snd_kcontrol *kcontrol,
814                                 struct snd_ctl_elem_info *info)
815 {
816         static const char *const names[] = { "None", "CD Player" };
817
818         return snd_ctl_enum_info(info, 1, 2, names);
819 }
820
821 static int snd_dummy_iobox_get(struct snd_kcontrol *kcontrol,
822                                struct snd_ctl_elem_value *value)
823 {
824         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
825
826         value->value.enumerated.item[0] = dummy->iobox;
827         return 0;
828 }
829
830 static int snd_dummy_iobox_put(struct snd_kcontrol *kcontrol,
831                                struct snd_ctl_elem_value *value)
832 {
833         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
834         int changed;
835
836         if (value->value.enumerated.item[0] > 1)
837                 return -EINVAL;
838
839         changed = value->value.enumerated.item[0] != dummy->iobox;
840         if (changed) {
841                 dummy->iobox = value->value.enumerated.item[0];
842
843                 if (dummy->iobox) {
844                         dummy->cd_volume_ctl->vd[0].access &=
845                                 ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
846                         dummy->cd_switch_ctl->vd[0].access &=
847                                 ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
848                 } else {
849                         dummy->cd_volume_ctl->vd[0].access |=
850                                 SNDRV_CTL_ELEM_ACCESS_INACTIVE;
851                         dummy->cd_switch_ctl->vd[0].access |=
852                                 SNDRV_CTL_ELEM_ACCESS_INACTIVE;
853                 }
854
855                 snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
856                                &dummy->cd_volume_ctl->id);
857                 snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
858                                &dummy->cd_switch_ctl->id);
859         }
860
861         return changed;
862 }
863
864 static struct snd_kcontrol_new snd_dummy_controls[] = {
865 DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
866 DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
867 DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
868 DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
869 DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
870 DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
871 DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
872 DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
873 DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
874 DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD),
875 {
876         .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
877         .name  = "External I/O Box",
878         .info  = snd_dummy_iobox_info,
879         .get   = snd_dummy_iobox_get,
880         .put   = snd_dummy_iobox_put,
881 },
882 };
883
884 static int snd_card_dummy_new_mixer(struct snd_dummy *dummy)
885 {
886         struct snd_card *card = dummy->card;
887         struct snd_kcontrol *kcontrol;
888         unsigned int idx;
889         int err;
890
891         spin_lock_init(&dummy->mixer_lock);
892         strcpy(card->mixername, "Dummy Mixer");
893         dummy->iobox = 1;
894
895         for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
896                 kcontrol = snd_ctl_new1(&snd_dummy_controls[idx], dummy);
897                 err = snd_ctl_add(card, kcontrol);
898                 if (err < 0)
899                         return err;
900                 if (!strcmp(kcontrol->id.name, "CD Volume"))
901                         dummy->cd_volume_ctl = kcontrol;
902                 else if (!strcmp(kcontrol->id.name, "CD Capture Switch"))
903                         dummy->cd_switch_ctl = kcontrol;
904
905         }
906         return 0;
907 }
908
909 #if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_PROC_FS)
910 /*
911  * proc interface
912  */
913 static void print_formats(struct snd_dummy *dummy,
914                           struct snd_info_buffer *buffer)
915 {
916         int i;
917
918         for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
919                 if (dummy->pcm_hw.formats & (1ULL << i))
920                         snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
921         }
922 }
923
924 static void print_rates(struct snd_dummy *dummy,
925                         struct snd_info_buffer *buffer)
926 {
927         static int rates[] = {
928                 5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
929                 64000, 88200, 96000, 176400, 192000,
930         };
931         int i;
932
933         if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_CONTINUOUS)
934                 snd_iprintf(buffer, " continuous");
935         if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_KNOT)
936                 snd_iprintf(buffer, " knot");
937         for (i = 0; i < ARRAY_SIZE(rates); i++)
938                 if (dummy->pcm_hw.rates & (1 << i))
939                         snd_iprintf(buffer, " %d", rates[i]);
940 }
941
942 #define get_dummy_int_ptr(dummy, ofs) \
943         (unsigned int *)((char *)&((dummy)->pcm_hw) + (ofs))
944 #define get_dummy_ll_ptr(dummy, ofs) \
945         (unsigned long long *)((char *)&((dummy)->pcm_hw) + (ofs))
946
947 struct dummy_hw_field {
948         const char *name;
949         const char *format;
950         unsigned int offset;
951         unsigned int size;
952 };
953 #define FIELD_ENTRY(item, fmt) {                   \
954         .name = #item,                             \
955         .format = fmt,                             \
956         .offset = offsetof(struct snd_pcm_hardware, item), \
957         .size = sizeof(dummy_pcm_hardware.item) }
958
959 static struct dummy_hw_field fields[] = {
960         FIELD_ENTRY(formats, "%#llx"),
961         FIELD_ENTRY(rates, "%#x"),
962         FIELD_ENTRY(rate_min, "%d"),
963         FIELD_ENTRY(rate_max, "%d"),
964         FIELD_ENTRY(channels_min, "%d"),
965         FIELD_ENTRY(channels_max, "%d"),
966         FIELD_ENTRY(buffer_bytes_max, "%ld"),
967         FIELD_ENTRY(period_bytes_min, "%ld"),
968         FIELD_ENTRY(period_bytes_max, "%ld"),
969         FIELD_ENTRY(periods_min, "%d"),
970         FIELD_ENTRY(periods_max, "%d"),
971 };
972
973 static void dummy_proc_read(struct snd_info_entry *entry,
974                             struct snd_info_buffer *buffer)
975 {
976         struct snd_dummy *dummy = entry->private_data;
977         int i;
978
979         for (i = 0; i < ARRAY_SIZE(fields); i++) {
980                 snd_iprintf(buffer, "%s ", fields[i].name);
981                 if (fields[i].size == sizeof(int))
982                         snd_iprintf(buffer, fields[i].format,
983                                 *get_dummy_int_ptr(dummy, fields[i].offset));
984                 else
985                         snd_iprintf(buffer, fields[i].format,
986                                 *get_dummy_ll_ptr(dummy, fields[i].offset));
987                 if (!strcmp(fields[i].name, "formats"))
988                         print_formats(dummy, buffer);
989                 else if (!strcmp(fields[i].name, "rates"))
990                         print_rates(dummy, buffer);
991                 snd_iprintf(buffer, "\n");
992         }
993 }
994
995 static void dummy_proc_write(struct snd_info_entry *entry,
996                              struct snd_info_buffer *buffer)
997 {
998         struct snd_dummy *dummy = entry->private_data;
999         char line[64];
1000
1001         while (!snd_info_get_line(buffer, line, sizeof(line))) {
1002                 char item[20];
1003                 const char *ptr;
1004                 unsigned long long val;
1005                 int i;
1006
1007                 ptr = snd_info_get_str(item, line, sizeof(item));
1008                 for (i = 0; i < ARRAY_SIZE(fields); i++) {
1009                         if (!strcmp(item, fields[i].name))
1010                                 break;
1011                 }
1012                 if (i >= ARRAY_SIZE(fields))
1013                         continue;
1014                 snd_info_get_str(item, ptr, sizeof(item));
1015                 if (kstrtoull(item, 0, &val))
1016                         continue;
1017                 if (fields[i].size == sizeof(int))
1018                         *get_dummy_int_ptr(dummy, fields[i].offset) = val;
1019                 else
1020                         *get_dummy_ll_ptr(dummy, fields[i].offset) = val;
1021         }
1022 }
1023
1024 static void dummy_proc_init(struct snd_dummy *chip)
1025 {
1026         snd_card_rw_proc_new(chip->card, "dummy_pcm", chip,
1027                              dummy_proc_read, dummy_proc_write);
1028 }
1029 #else
1030 #define dummy_proc_init(x)
1031 #endif /* CONFIG_SND_DEBUG && CONFIG_SND_PROC_FS */
1032
1033 static int snd_dummy_probe(struct platform_device *devptr)
1034 {
1035         struct snd_card *card;
1036         struct snd_dummy *dummy;
1037         struct dummy_model *m = NULL, **mdl;
1038         int idx, err;
1039         int dev = devptr->id;
1040
1041         err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
1042                            sizeof(struct snd_dummy), &card);
1043         if (err < 0)
1044                 return err;
1045         dummy = card->private_data;
1046         dummy->card = card;
1047         for (mdl = dummy_models; *mdl && model[dev]; mdl++) {
1048                 if (strcmp(model[dev], (*mdl)->name) == 0) {
1049                         printk(KERN_INFO
1050                                 "snd-dummy: Using model '%s' for card %i\n",
1051                                 (*mdl)->name, card->number);
1052                         m = dummy->model = *mdl;
1053                         break;
1054                 }
1055         }
1056         for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1057                 if (pcm_substreams[dev] < 1)
1058                         pcm_substreams[dev] = 1;
1059                 if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1060                         pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1061                 err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1062                 if (err < 0)
1063                         goto __nodev;
1064         }
1065
1066         dummy->pcm_hw = dummy_pcm_hardware;
1067         if (m) {
1068                 if (m->formats)
1069                         dummy->pcm_hw.formats = m->formats;
1070                 if (m->buffer_bytes_max)
1071                         dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1072                 if (m->period_bytes_min)
1073                         dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1074                 if (m->period_bytes_max)
1075                         dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1076                 if (m->periods_min)
1077                         dummy->pcm_hw.periods_min = m->periods_min;
1078                 if (m->periods_max)
1079                         dummy->pcm_hw.periods_max = m->periods_max;
1080                 if (m->rates)
1081                         dummy->pcm_hw.rates = m->rates;
1082                 if (m->rate_min)
1083                         dummy->pcm_hw.rate_min = m->rate_min;
1084                 if (m->rate_max)
1085                         dummy->pcm_hw.rate_max = m->rate_max;
1086                 if (m->channels_min)
1087                         dummy->pcm_hw.channels_min = m->channels_min;
1088                 if (m->channels_max)
1089                         dummy->pcm_hw.channels_max = m->channels_max;
1090         }
1091
1092         err = snd_card_dummy_new_mixer(dummy);
1093         if (err < 0)
1094                 goto __nodev;
1095         strcpy(card->driver, "Dummy");
1096         strcpy(card->shortname, "Dummy");
1097         sprintf(card->longname, "Dummy %i", dev + 1);
1098
1099         dummy_proc_init(dummy);
1100
1101         err = snd_card_register(card);
1102         if (err == 0) {
1103                 platform_set_drvdata(devptr, card);
1104                 return 0;
1105         }
1106       __nodev:
1107         snd_card_free(card);
1108         return err;
1109 }
1110
1111 static int snd_dummy_remove(struct platform_device *devptr)
1112 {
1113         snd_card_free(platform_get_drvdata(devptr));
1114         return 0;
1115 }
1116
1117 #ifdef CONFIG_PM_SLEEP
1118 static int snd_dummy_suspend(struct device *pdev)
1119 {
1120         struct snd_card *card = dev_get_drvdata(pdev);
1121
1122         snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
1123         return 0;
1124 }
1125         
1126 static int snd_dummy_resume(struct device *pdev)
1127 {
1128         struct snd_card *card = dev_get_drvdata(pdev);
1129
1130         snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1131         return 0;
1132 }
1133
1134 static SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
1135 #define SND_DUMMY_PM_OPS        &snd_dummy_pm
1136 #else
1137 #define SND_DUMMY_PM_OPS        NULL
1138 #endif
1139
1140 #define SND_DUMMY_DRIVER        "snd_dummy"
1141
1142 static struct platform_driver snd_dummy_driver = {
1143         .probe          = snd_dummy_probe,
1144         .remove         = snd_dummy_remove,
1145         .driver         = {
1146                 .name   = SND_DUMMY_DRIVER,
1147                 .pm     = SND_DUMMY_PM_OPS,
1148         },
1149 };
1150
1151 static void snd_dummy_unregister_all(void)
1152 {
1153         int i;
1154
1155         for (i = 0; i < ARRAY_SIZE(devices); ++i)
1156                 platform_device_unregister(devices[i]);
1157         platform_driver_unregister(&snd_dummy_driver);
1158         free_fake_buffer();
1159 }
1160
1161 static int __init alsa_card_dummy_init(void)
1162 {
1163         int i, cards, err;
1164
1165         err = platform_driver_register(&snd_dummy_driver);
1166         if (err < 0)
1167                 return err;
1168
1169         err = alloc_fake_buffer();
1170         if (err < 0) {
1171                 platform_driver_unregister(&snd_dummy_driver);
1172                 return err;
1173         }
1174
1175         cards = 0;
1176         for (i = 0; i < SNDRV_CARDS; i++) {
1177                 struct platform_device *device;
1178                 if (! enable[i])
1179                         continue;
1180                 device = platform_device_register_simple(SND_DUMMY_DRIVER,
1181                                                          i, NULL, 0);
1182                 if (IS_ERR(device))
1183                         continue;
1184                 if (!platform_get_drvdata(device)) {
1185                         platform_device_unregister(device);
1186                         continue;
1187                 }
1188                 devices[i] = device;
1189                 cards++;
1190         }
1191         if (!cards) {
1192 #ifdef MODULE
1193                 printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1194 #endif
1195                 snd_dummy_unregister_all();
1196                 return -ENODEV;
1197         }
1198         return 0;
1199 }
1200
1201 static void __exit alsa_card_dummy_exit(void)
1202 {
1203         snd_dummy_unregister_all();
1204 }
1205
1206 module_init(alsa_card_dummy_init)
1207 module_exit(alsa_card_dummy_exit)