Root/sound/core/pcm_lib.c

1/*
2 * Digital Audio (PCM) abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 * Abramo Bagnara <abramo@alsa-project.org>
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 */
22
23#include <linux/slab.h>
24#include <linux/time.h>
25#include <linux/math64.h>
26#include <sound/core.h>
27#include <sound/control.h>
28#include <sound/info.h>
29#include <sound/pcm.h>
30#include <sound/pcm_params.h>
31#include <sound/timer.h>
32
33/*
34 * fill ring buffer with silence
35 * runtime->silence_start: starting pointer to silence area
36 * runtime->silence_filled: size filled with silence
37 * runtime->silence_threshold: threshold from application
38 * runtime->silence_size: maximal size from application
39 *
40 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
41 */
42void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
43{
44    struct snd_pcm_runtime *runtime = substream->runtime;
45    snd_pcm_uframes_t frames, ofs, transfer;
46
47    if (runtime->silence_size < runtime->boundary) {
48        snd_pcm_sframes_t noise_dist, n;
49        if (runtime->silence_start != runtime->control->appl_ptr) {
50            n = runtime->control->appl_ptr - runtime->silence_start;
51            if (n < 0)
52                n += runtime->boundary;
53            if ((snd_pcm_uframes_t)n < runtime->silence_filled)
54                runtime->silence_filled -= n;
55            else
56                runtime->silence_filled = 0;
57            runtime->silence_start = runtime->control->appl_ptr;
58        }
59        if (runtime->silence_filled >= runtime->buffer_size)
60            return;
61        noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
62        if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
63            return;
64        frames = runtime->silence_threshold - noise_dist;
65        if (frames > runtime->silence_size)
66            frames = runtime->silence_size;
67    } else {
68        if (new_hw_ptr == ULONG_MAX) { /* initialization */
69            snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
70            if (avail > runtime->buffer_size)
71                avail = runtime->buffer_size;
72            runtime->silence_filled = avail > 0 ? avail : 0;
73            runtime->silence_start = (runtime->status->hw_ptr +
74                          runtime->silence_filled) %
75                         runtime->boundary;
76        } else {
77            ofs = runtime->status->hw_ptr;
78            frames = new_hw_ptr - ofs;
79            if ((snd_pcm_sframes_t)frames < 0)
80                frames += runtime->boundary;
81            runtime->silence_filled -= frames;
82            if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
83                runtime->silence_filled = 0;
84                runtime->silence_start = new_hw_ptr;
85            } else {
86                runtime->silence_start = ofs;
87            }
88        }
89        frames = runtime->buffer_size - runtime->silence_filled;
90    }
91    if (snd_BUG_ON(frames > runtime->buffer_size))
92        return;
93    if (frames == 0)
94        return;
95    ofs = runtime->silence_start % runtime->buffer_size;
96    while (frames > 0) {
97        transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
98        if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
99            runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
100            if (substream->ops->silence) {
101                int err;
102                err = substream->ops->silence(substream, -1, ofs, transfer);
103                snd_BUG_ON(err < 0);
104            } else {
105                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
106                snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
107            }
108        } else {
109            unsigned int c;
110            unsigned int channels = runtime->channels;
111            if (substream->ops->silence) {
112                for (c = 0; c < channels; ++c) {
113                    int err;
114                    err = substream->ops->silence(substream, c, ofs, transfer);
115                    snd_BUG_ON(err < 0);
116                }
117            } else {
118                size_t dma_csize = runtime->dma_bytes / channels;
119                for (c = 0; c < channels; ++c) {
120                    char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
121                    snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
122                }
123            }
124        }
125        runtime->silence_filled += transfer;
126        frames -= transfer;
127        ofs = 0;
128    }
129}
130
131#ifdef CONFIG_SND_DEBUG
132void snd_pcm_debug_name(struct snd_pcm_substream *substream,
133               char *name, size_t len)
134{
135    snprintf(name, len, "pcmC%dD%d%c:%d",
136         substream->pcm->card->number,
137         substream->pcm->device,
138         substream->stream ? 'c' : 'p',
139         substream->number);
140}
141EXPORT_SYMBOL(snd_pcm_debug_name);
142#endif
143
144#define XRUN_DEBUG_BASIC (1<<0)
145#define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
146#define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
147#define XRUN_DEBUG_PERIODUPDATE (1<<3) /* full period update info */
148#define XRUN_DEBUG_HWPTRUPDATE (1<<4) /* full hwptr update info */
149#define XRUN_DEBUG_LOG (1<<5) /* show last 10 positions on err */
150#define XRUN_DEBUG_LOGONCE (1<<6) /* do above only once */
151
152#ifdef CONFIG_SND_PCM_XRUN_DEBUG
153
154#define xrun_debug(substream, mask) \
155            ((substream)->pstr->xrun_debug & (mask))
156#else
157#define xrun_debug(substream, mask) 0
158#endif
159
160#define dump_stack_on_xrun(substream) do { \
161        if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
162            dump_stack(); \
163    } while (0)
164
165static void xrun(struct snd_pcm_substream *substream)
166{
167    struct snd_pcm_runtime *runtime = substream->runtime;
168
169    if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
170        snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
171    snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
172    if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
173        char name[16];
174        snd_pcm_debug_name(substream, name, sizeof(name));
175        snd_printd(KERN_DEBUG "XRUN: %s\n", name);
176        dump_stack_on_xrun(substream);
177    }
178}
179
180#ifdef CONFIG_SND_PCM_XRUN_DEBUG
181#define hw_ptr_error(substream, fmt, args...) \
182    do { \
183        if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
184            xrun_log_show(substream); \
185            if (printk_ratelimit()) { \
186                snd_printd("PCM: " fmt, ##args); \
187            } \
188            dump_stack_on_xrun(substream); \
189        } \
190    } while (0)
191
192#define XRUN_LOG_CNT 10
193
194struct hwptr_log_entry {
195    unsigned int in_interrupt;
196    unsigned long jiffies;
197    snd_pcm_uframes_t pos;
198    snd_pcm_uframes_t period_size;
199    snd_pcm_uframes_t buffer_size;
200    snd_pcm_uframes_t old_hw_ptr;
201    snd_pcm_uframes_t hw_ptr_base;
202};
203
204struct snd_pcm_hwptr_log {
205    unsigned int idx;
206    unsigned int hit: 1;
207    struct hwptr_log_entry entries[XRUN_LOG_CNT];
208};
209
210static void xrun_log(struct snd_pcm_substream *substream,
211             snd_pcm_uframes_t pos, int in_interrupt)
212{
213    struct snd_pcm_runtime *runtime = substream->runtime;
214    struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
215    struct hwptr_log_entry *entry;
216
217    if (log == NULL) {
218        log = kzalloc(sizeof(*log), GFP_ATOMIC);
219        if (log == NULL)
220            return;
221        runtime->hwptr_log = log;
222    } else {
223        if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
224            return;
225    }
226    entry = &log->entries[log->idx];
227    entry->in_interrupt = in_interrupt;
228    entry->jiffies = jiffies;
229    entry->pos = pos;
230    entry->period_size = runtime->period_size;
231    entry->buffer_size = runtime->buffer_size;
232    entry->old_hw_ptr = runtime->status->hw_ptr;
233    entry->hw_ptr_base = runtime->hw_ptr_base;
234    log->idx = (log->idx + 1) % XRUN_LOG_CNT;
235}
236
237static void xrun_log_show(struct snd_pcm_substream *substream)
238{
239    struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
240    struct hwptr_log_entry *entry;
241    char name[16];
242    unsigned int idx;
243    int cnt;
244
245    if (log == NULL)
246        return;
247    if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
248        return;
249    snd_pcm_debug_name(substream, name, sizeof(name));
250    for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
251        entry = &log->entries[idx];
252        if (entry->period_size == 0)
253            break;
254        snd_printd("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
255               "hwptr=%ld/%ld\n",
256               name, entry->in_interrupt ? "[Q] " : "",
257               entry->jiffies,
258               (unsigned long)entry->pos,
259               (unsigned long)entry->period_size,
260               (unsigned long)entry->buffer_size,
261               (unsigned long)entry->old_hw_ptr,
262               (unsigned long)entry->hw_ptr_base);
263        idx++;
264        idx %= XRUN_LOG_CNT;
265    }
266    log->hit = 1;
267}
268
269#else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
270
271#define hw_ptr_error(substream, fmt, args...) do { } while (0)
272#define xrun_log(substream, pos, in_interrupt) do { } while (0)
273#define xrun_log_show(substream) do { } while (0)
274
275#endif
276
277int snd_pcm_update_state(struct snd_pcm_substream *substream,
278             struct snd_pcm_runtime *runtime)
279{
280    snd_pcm_uframes_t avail;
281
282    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
283        avail = snd_pcm_playback_avail(runtime);
284    else
285        avail = snd_pcm_capture_avail(runtime);
286    if (avail > runtime->avail_max)
287        runtime->avail_max = avail;
288    if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
289        if (avail >= runtime->buffer_size) {
290            snd_pcm_drain_done(substream);
291            return -EPIPE;
292        }
293    } else {
294        if (avail >= runtime->stop_threshold) {
295            xrun(substream);
296            return -EPIPE;
297        }
298    }
299    if (runtime->twake) {
300        if (avail >= runtime->twake)
301            wake_up(&runtime->tsleep);
302    } else if (avail >= runtime->control->avail_min)
303        wake_up(&runtime->sleep);
304    return 0;
305}
306
307static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
308                  unsigned int in_interrupt)
309{
310    struct snd_pcm_runtime *runtime = substream->runtime;
311    snd_pcm_uframes_t pos;
312    snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
313    snd_pcm_sframes_t hdelta, delta;
314    unsigned long jdelta;
315
316    old_hw_ptr = runtime->status->hw_ptr;
317    pos = substream->ops->pointer(substream);
318    if (pos == SNDRV_PCM_POS_XRUN) {
319        xrun(substream);
320        return -EPIPE;
321    }
322    if (pos >= runtime->buffer_size) {
323        if (printk_ratelimit()) {
324            char name[16];
325            snd_pcm_debug_name(substream, name, sizeof(name));
326            xrun_log_show(substream);
327            snd_printd(KERN_ERR "BUG: %s, pos = %ld, "
328                   "buffer size = %ld, period size = %ld\n",
329                   name, pos, runtime->buffer_size,
330                   runtime->period_size);
331        }
332        pos = 0;
333    }
334    pos -= pos % runtime->min_align;
335    if (xrun_debug(substream, XRUN_DEBUG_LOG))
336        xrun_log(substream, pos, in_interrupt);
337    hw_base = runtime->hw_ptr_base;
338    new_hw_ptr = hw_base + pos;
339    if (in_interrupt) {
340        /* we know that one period was processed */
341        /* delta = "expected next hw_ptr" for in_interrupt != 0 */
342        delta = runtime->hw_ptr_interrupt + runtime->period_size;
343        if (delta > new_hw_ptr) {
344            /* check for double acknowledged interrupts */
345            hdelta = jiffies - runtime->hw_ptr_jiffies;
346            if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
347                hw_base += runtime->buffer_size;
348                if (hw_base >= runtime->boundary)
349                    hw_base = 0;
350                new_hw_ptr = hw_base + pos;
351                goto __delta;
352            }
353        }
354    }
355    /* new_hw_ptr might be lower than old_hw_ptr in case when */
356    /* pointer crosses the end of the ring buffer */
357    if (new_hw_ptr < old_hw_ptr) {
358        hw_base += runtime->buffer_size;
359        if (hw_base >= runtime->boundary)
360            hw_base = 0;
361        new_hw_ptr = hw_base + pos;
362    }
363      __delta:
364    delta = new_hw_ptr - old_hw_ptr;
365    if (delta < 0)
366        delta += runtime->boundary;
367    if (xrun_debug(substream, in_interrupt ?
368            XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
369        char name[16];
370        snd_pcm_debug_name(substream, name, sizeof(name));
371        snd_printd("%s_update: %s: pos=%u/%u/%u, "
372               "hwptr=%ld/%ld/%ld/%ld\n",
373               in_interrupt ? "period" : "hwptr",
374               name,
375               (unsigned int)pos,
376               (unsigned int)runtime->period_size,
377               (unsigned int)runtime->buffer_size,
378               (unsigned long)delta,
379               (unsigned long)old_hw_ptr,
380               (unsigned long)new_hw_ptr,
381               (unsigned long)runtime->hw_ptr_base);
382    }
383
384    if (runtime->no_period_wakeup) {
385        snd_pcm_sframes_t xrun_threshold;
386        /*
387         * Without regular period interrupts, we have to check
388         * the elapsed time to detect xruns.
389         */
390        jdelta = jiffies - runtime->hw_ptr_jiffies;
391        if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
392            goto no_delta_check;
393        hdelta = jdelta - delta * HZ / runtime->rate;
394        xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
395        while (hdelta > xrun_threshold) {
396            delta += runtime->buffer_size;
397            hw_base += runtime->buffer_size;
398            if (hw_base >= runtime->boundary)
399                hw_base = 0;
400            new_hw_ptr = hw_base + pos;
401            hdelta -= runtime->hw_ptr_buffer_jiffies;
402        }
403        goto no_delta_check;
404    }
405
406    /* something must be really wrong */
407    if (delta >= runtime->buffer_size + runtime->period_size) {
408        hw_ptr_error(substream,
409                   "Unexpected hw_pointer value %s"
410                   "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
411                   "old_hw_ptr=%ld)\n",
412                     in_interrupt ? "[Q] " : "[P]",
413                     substream->stream, (long)pos,
414                     (long)new_hw_ptr, (long)old_hw_ptr);
415        return 0;
416    }
417
418    /* Do jiffies check only in xrun_debug mode */
419    if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
420        goto no_jiffies_check;
421
422    /* Skip the jiffies check for hardwares with BATCH flag.
423     * Such hardware usually just increases the position at each IRQ,
424     * thus it can't give any strange position.
425     */
426    if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
427        goto no_jiffies_check;
428    hdelta = delta;
429    if (hdelta < runtime->delay)
430        goto no_jiffies_check;
431    hdelta -= runtime->delay;
432    jdelta = jiffies - runtime->hw_ptr_jiffies;
433    if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
434        delta = jdelta /
435            (((runtime->period_size * HZ) / runtime->rate)
436                                + HZ/100);
437        /* move new_hw_ptr according jiffies not pos variable */
438        new_hw_ptr = old_hw_ptr;
439        hw_base = delta;
440        /* use loop to avoid checks for delta overflows */
441        /* the delta value is small or zero in most cases */
442        while (delta > 0) {
443            new_hw_ptr += runtime->period_size;
444            if (new_hw_ptr >= runtime->boundary)
445                new_hw_ptr -= runtime->boundary;
446            delta--;
447        }
448        /* align hw_base to buffer_size */
449        hw_ptr_error(substream,
450                 "hw_ptr skipping! %s"
451                 "(pos=%ld, delta=%ld, period=%ld, "
452                 "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
453                 in_interrupt ? "[Q] " : "",
454                 (long)pos, (long)hdelta,
455                 (long)runtime->period_size, jdelta,
456                 ((hdelta * HZ) / runtime->rate), hw_base,
457                 (unsigned long)old_hw_ptr,
458                 (unsigned long)new_hw_ptr);
459        /* reset values to proper state */
460        delta = 0;
461        hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
462    }
463 no_jiffies_check:
464    if (delta > runtime->period_size + runtime->period_size / 2) {
465        hw_ptr_error(substream,
466                 "Lost interrupts? %s"
467                 "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
468                 "old_hw_ptr=%ld)\n",
469                 in_interrupt ? "[Q] " : "",
470                 substream->stream, (long)delta,
471                 (long)new_hw_ptr,
472                 (long)old_hw_ptr);
473    }
474
475 no_delta_check:
476    if (runtime->status->hw_ptr == new_hw_ptr)
477        return 0;
478
479    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
480        runtime->silence_size > 0)
481        snd_pcm_playback_silence(substream, new_hw_ptr);
482
483    if (in_interrupt) {
484        delta = new_hw_ptr - runtime->hw_ptr_interrupt;
485        if (delta < 0)
486            delta += runtime->boundary;
487        delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
488        runtime->hw_ptr_interrupt += delta;
489        if (runtime->hw_ptr_interrupt >= runtime->boundary)
490            runtime->hw_ptr_interrupt -= runtime->boundary;
491    }
492    runtime->hw_ptr_base = hw_base;
493    runtime->status->hw_ptr = new_hw_ptr;
494    runtime->hw_ptr_jiffies = jiffies;
495    if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
496        snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
497
498    return snd_pcm_update_state(substream, runtime);
499}
500
501/* CAUTION: call it with irq disabled */
502int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
503{
504    return snd_pcm_update_hw_ptr0(substream, 0);
505}
506
507/**
508 * snd_pcm_set_ops - set the PCM operators
509 * @pcm: the pcm instance
510 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
511 * @ops: the operator table
512 *
513 * Sets the given PCM operators to the pcm instance.
514 */
515void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
516{
517    struct snd_pcm_str *stream = &pcm->streams[direction];
518    struct snd_pcm_substream *substream;
519    
520    for (substream = stream->substream; substream != NULL; substream = substream->next)
521        substream->ops = ops;
522}
523
524EXPORT_SYMBOL(snd_pcm_set_ops);
525
526/**
527 * snd_pcm_sync - set the PCM sync id
528 * @substream: the pcm substream
529 *
530 * Sets the PCM sync identifier for the card.
531 */
532void snd_pcm_set_sync(struct snd_pcm_substream *substream)
533{
534    struct snd_pcm_runtime *runtime = substream->runtime;
535    
536    runtime->sync.id32[0] = substream->pcm->card->number;
537    runtime->sync.id32[1] = -1;
538    runtime->sync.id32[2] = -1;
539    runtime->sync.id32[3] = -1;
540}
541
542EXPORT_SYMBOL(snd_pcm_set_sync);
543
544/*
545 * Standard ioctl routine
546 */
547
548static inline unsigned int div32(unsigned int a, unsigned int b,
549                 unsigned int *r)
550{
551    if (b == 0) {
552        *r = 0;
553        return UINT_MAX;
554    }
555    *r = a % b;
556    return a / b;
557}
558
559static inline unsigned int div_down(unsigned int a, unsigned int b)
560{
561    if (b == 0)
562        return UINT_MAX;
563    return a / b;
564}
565
566static inline unsigned int div_up(unsigned int a, unsigned int b)
567{
568    unsigned int r;
569    unsigned int q;
570    if (b == 0)
571        return UINT_MAX;
572    q = div32(a, b, &r);
573    if (r)
574        ++q;
575    return q;
576}
577
578static inline unsigned int mul(unsigned int a, unsigned int b)
579{
580    if (a == 0)
581        return 0;
582    if (div_down(UINT_MAX, a) < b)
583        return UINT_MAX;
584    return a * b;
585}
586
587static inline unsigned int muldiv32(unsigned int a, unsigned int b,
588                    unsigned int c, unsigned int *r)
589{
590    u_int64_t n = (u_int64_t) a * b;
591    if (c == 0) {
592        snd_BUG_ON(!n);
593        *r = 0;
594        return UINT_MAX;
595    }
596    n = div_u64_rem(n, c, r);
597    if (n >= UINT_MAX) {
598        *r = 0;
599        return UINT_MAX;
600    }
601    return n;
602}
603
604/**
605 * snd_interval_refine - refine the interval value of configurator
606 * @i: the interval value to refine
607 * @v: the interval value to refer to
608 *
609 * Refines the interval value with the reference value.
610 * The interval is changed to the range satisfying both intervals.
611 * The interval status (min, max, integer, etc.) are evaluated.
612 *
613 * Returns non-zero if the value is changed, zero if not changed.
614 */
615int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
616{
617    int changed = 0;
618    if (snd_BUG_ON(snd_interval_empty(i)))
619        return -EINVAL;
620    if (i->min < v->min) {
621        i->min = v->min;
622        i->openmin = v->openmin;
623        changed = 1;
624    } else if (i->min == v->min && !i->openmin && v->openmin) {
625        i->openmin = 1;
626        changed = 1;
627    }
628    if (i->max > v->max) {
629        i->max = v->max;
630        i->openmax = v->openmax;
631        changed = 1;
632    } else if (i->max == v->max && !i->openmax && v->openmax) {
633        i->openmax = 1;
634        changed = 1;
635    }
636    if (!i->integer && v->integer) {
637        i->integer = 1;
638        changed = 1;
639    }
640    if (i->integer) {
641        if (i->openmin) {
642            i->min++;
643            i->openmin = 0;
644        }
645        if (i->openmax) {
646            i->max--;
647            i->openmax = 0;
648        }
649    } else if (!i->openmin && !i->openmax && i->min == i->max)
650        i->integer = 1;
651    if (snd_interval_checkempty(i)) {
652        snd_interval_none(i);
653        return -EINVAL;
654    }
655    return changed;
656}
657
658EXPORT_SYMBOL(snd_interval_refine);
659
660static int snd_interval_refine_first(struct snd_interval *i)
661{
662    if (snd_BUG_ON(snd_interval_empty(i)))
663        return -EINVAL;
664    if (snd_interval_single(i))
665        return 0;
666    i->max = i->min;
667    i->openmax = i->openmin;
668    if (i->openmax)
669        i->max++;
670    return 1;
671}
672
673static int snd_interval_refine_last(struct snd_interval *i)
674{
675    if (snd_BUG_ON(snd_interval_empty(i)))
676        return -EINVAL;
677    if (snd_interval_single(i))
678        return 0;
679    i->min = i->max;
680    i->openmin = i->openmax;
681    if (i->openmin)
682        i->min--;
683    return 1;
684}
685
686void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
687{
688    if (a->empty || b->empty) {
689        snd_interval_none(c);
690        return;
691    }
692    c->empty = 0;
693    c->min = mul(a->min, b->min);
694    c->openmin = (a->openmin || b->openmin);
695    c->max = mul(a->max, b->max);
696    c->openmax = (a->openmax || b->openmax);
697    c->integer = (a->integer && b->integer);
698}
699
700/**
701 * snd_interval_div - refine the interval value with division
702 * @a: dividend
703 * @b: divisor
704 * @c: quotient
705 *
706 * c = a / b
707 *
708 * Returns non-zero if the value is changed, zero if not changed.
709 */
710void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
711{
712    unsigned int r;
713    if (a->empty || b->empty) {
714        snd_interval_none(c);
715        return;
716    }
717    c->empty = 0;
718    c->min = div32(a->min, b->max, &r);
719    c->openmin = (r || a->openmin || b->openmax);
720    if (b->min > 0) {
721        c->max = div32(a->max, b->min, &r);
722        if (r) {
723            c->max++;
724            c->openmax = 1;
725        } else
726            c->openmax = (a->openmax || b->openmin);
727    } else {
728        c->max = UINT_MAX;
729        c->openmax = 0;
730    }
731    c->integer = 0;
732}
733
734/**
735 * snd_interval_muldivk - refine the interval value
736 * @a: dividend 1
737 * @b: dividend 2
738 * @k: divisor (as integer)
739 * @c: result
740  *
741 * c = a * b / k
742 *
743 * Returns non-zero if the value is changed, zero if not changed.
744 */
745void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
746              unsigned int k, struct snd_interval *c)
747{
748    unsigned int r;
749    if (a->empty || b->empty) {
750        snd_interval_none(c);
751        return;
752    }
753    c->empty = 0;
754    c->min = muldiv32(a->min, b->min, k, &r);
755    c->openmin = (r || a->openmin || b->openmin);
756    c->max = muldiv32(a->max, b->max, k, &r);
757    if (r) {
758        c->max++;
759        c->openmax = 1;
760    } else
761        c->openmax = (a->openmax || b->openmax);
762    c->integer = 0;
763}
764
765/**
766 * snd_interval_mulkdiv - refine the interval value
767 * @a: dividend 1
768 * @k: dividend 2 (as integer)
769 * @b: divisor
770 * @c: result
771 *
772 * c = a * k / b
773 *
774 * Returns non-zero if the value is changed, zero if not changed.
775 */
776void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
777              const struct snd_interval *b, struct snd_interval *c)
778{
779    unsigned int r;
780    if (a->empty || b->empty) {
781        snd_interval_none(c);
782        return;
783    }
784    c->empty = 0;
785    c->min = muldiv32(a->min, k, b->max, &r);
786    c->openmin = (r || a->openmin || b->openmax);
787    if (b->min > 0) {
788        c->max = muldiv32(a->max, k, b->min, &r);
789        if (r) {
790            c->max++;
791            c->openmax = 1;
792        } else
793            c->openmax = (a->openmax || b->openmin);
794    } else {
795        c->max = UINT_MAX;
796        c->openmax = 0;
797    }
798    c->integer = 0;
799}
800
801/* ---- */
802
803
804/**
805 * snd_interval_ratnum - refine the interval value
806 * @i: interval to refine
807 * @rats_count: number of ratnum_t
808 * @rats: ratnum_t array
809 * @nump: pointer to store the resultant numerator
810 * @denp: pointer to store the resultant denominator
811 *
812 * Returns non-zero if the value is changed, zero if not changed.
813 */
814int snd_interval_ratnum(struct snd_interval *i,
815            unsigned int rats_count, struct snd_ratnum *rats,
816            unsigned int *nump, unsigned int *denp)
817{
818    unsigned int best_num, best_den;
819    int best_diff;
820    unsigned int k;
821    struct snd_interval t;
822    int err;
823    unsigned int result_num, result_den;
824    int result_diff;
825
826    best_num = best_den = best_diff = 0;
827    for (k = 0; k < rats_count; ++k) {
828        unsigned int num = rats[k].num;
829        unsigned int den;
830        unsigned int q = i->min;
831        int diff;
832        if (q == 0)
833            q = 1;
834        den = div_up(num, q);
835        if (den < rats[k].den_min)
836            continue;
837        if (den > rats[k].den_max)
838            den = rats[k].den_max;
839        else {
840            unsigned int r;
841            r = (den - rats[k].den_min) % rats[k].den_step;
842            if (r != 0)
843                den -= r;
844        }
845        diff = num - q * den;
846        if (diff < 0)
847            diff = -diff;
848        if (best_num == 0 ||
849            diff * best_den < best_diff * den) {
850            best_diff = diff;
851            best_den = den;
852            best_num = num;
853        }
854    }
855    if (best_den == 0) {
856        i->empty = 1;
857        return -EINVAL;
858    }
859    t.min = div_down(best_num, best_den);
860    t.openmin = !!(best_num % best_den);
861    
862    result_num = best_num;
863    result_diff = best_diff;
864    result_den = best_den;
865    best_num = best_den = best_diff = 0;
866    for (k = 0; k < rats_count; ++k) {
867        unsigned int num = rats[k].num;
868        unsigned int den;
869        unsigned int q = i->max;
870        int diff;
871        if (q == 0) {
872            i->empty = 1;
873            return -EINVAL;
874        }
875        den = div_down(num, q);
876        if (den > rats[k].den_max)
877            continue;
878        if (den < rats[k].den_min)
879            den = rats[k].den_min;
880        else {
881            unsigned int r;
882            r = (den - rats[k].den_min) % rats[k].den_step;
883            if (r != 0)
884                den += rats[k].den_step - r;
885        }
886        diff = q * den - num;
887        if (diff < 0)
888            diff = -diff;
889        if (best_num == 0 ||
890            diff * best_den < best_diff * den) {
891            best_diff = diff;
892            best_den = den;
893            best_num = num;
894        }
895    }
896    if (best_den == 0) {
897        i->empty = 1;
898        return -EINVAL;
899    }
900    t.max = div_up(best_num, best_den);
901    t.openmax = !!(best_num % best_den);
902    t.integer = 0;
903    err = snd_interval_refine(i, &t);
904    if (err < 0)
905        return err;
906
907    if (snd_interval_single(i)) {
908        if (best_diff * result_den < result_diff * best_den) {
909            result_num = best_num;
910            result_den = best_den;
911        }
912        if (nump)
913            *nump = result_num;
914        if (denp)
915            *denp = result_den;
916    }
917    return err;
918}
919
920EXPORT_SYMBOL(snd_interval_ratnum);
921
922/**
923 * snd_interval_ratden - refine the interval value
924 * @i: interval to refine
925 * @rats_count: number of struct ratden
926 * @rats: struct ratden array
927 * @nump: pointer to store the resultant numerator
928 * @denp: pointer to store the resultant denominator
929 *
930 * Returns non-zero if the value is changed, zero if not changed.
931 */
932static int snd_interval_ratden(struct snd_interval *i,
933                   unsigned int rats_count, struct snd_ratden *rats,
934                   unsigned int *nump, unsigned int *denp)
935{
936    unsigned int best_num, best_diff, best_den;
937    unsigned int k;
938    struct snd_interval t;
939    int err;
940
941    best_num = best_den = best_diff = 0;
942    for (k = 0; k < rats_count; ++k) {
943        unsigned int num;
944        unsigned int den = rats[k].den;
945        unsigned int q = i->min;
946        int diff;
947        num = mul(q, den);
948        if (num > rats[k].num_max)
949            continue;
950        if (num < rats[k].num_min)
951            num = rats[k].num_max;
952        else {
953            unsigned int r;
954            r = (num - rats[k].num_min) % rats[k].num_step;
955            if (r != 0)
956                num += rats[k].num_step - r;
957        }
958        diff = num - q * den;
959        if (best_num == 0 ||
960            diff * best_den < best_diff * den) {
961            best_diff = diff;
962            best_den = den;
963            best_num = num;
964        }
965    }
966    if (best_den == 0) {
967        i->empty = 1;
968        return -EINVAL;
969    }
970    t.min = div_down(best_num, best_den);
971    t.openmin = !!(best_num % best_den);
972    
973    best_num = best_den = best_diff = 0;
974    for (k = 0; k < rats_count; ++k) {
975        unsigned int num;
976        unsigned int den = rats[k].den;
977        unsigned int q = i->max;
978        int diff;
979        num = mul(q, den);
980        if (num < rats[k].num_min)
981            continue;
982        if (num > rats[k].num_max)
983            num = rats[k].num_max;
984        else {
985            unsigned int r;
986            r = (num - rats[k].num_min) % rats[k].num_step;
987            if (r != 0)
988                num -= r;
989        }
990        diff = q * den - num;
991        if (best_num == 0 ||
992            diff * best_den < best_diff * den) {
993            best_diff = diff;
994            best_den = den;
995            best_num = num;
996        }
997    }
998    if (best_den == 0) {
999        i->empty = 1;
1000        return -EINVAL;
1001    }
1002    t.max = div_up(best_num, best_den);
1003    t.openmax = !!(best_num % best_den);
1004    t.integer = 0;
1005    err = snd_interval_refine(i, &t);
1006    if (err < 0)
1007        return err;
1008
1009    if (snd_interval_single(i)) {
1010        if (nump)
1011            *nump = best_num;
1012        if (denp)
1013            *denp = best_den;
1014    }
1015    return err;
1016}
1017
1018/**
1019 * snd_interval_list - refine the interval value from the list
1020 * @i: the interval value to refine
1021 * @count: the number of elements in the list
1022 * @list: the value list
1023 * @mask: the bit-mask to evaluate
1024 *
1025 * Refines the interval value from the list.
1026 * When mask is non-zero, only the elements corresponding to bit 1 are
1027 * evaluated.
1028 *
1029 * Returns non-zero if the value is changed, zero if not changed.
1030 */
1031int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
1032{
1033        unsigned int k;
1034    struct snd_interval list_range;
1035
1036    if (!count) {
1037        i->empty = 1;
1038        return -EINVAL;
1039    }
1040    snd_interval_any(&list_range);
1041    list_range.min = UINT_MAX;
1042    list_range.max = 0;
1043        for (k = 0; k < count; k++) {
1044        if (mask && !(mask & (1 << k)))
1045            continue;
1046        if (!snd_interval_test(i, list[k]))
1047            continue;
1048        list_range.min = min(list_range.min, list[k]);
1049        list_range.max = max(list_range.max, list[k]);
1050        }
1051    return snd_interval_refine(i, &list_range);
1052}
1053
1054EXPORT_SYMBOL(snd_interval_list);
1055
1056static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1057{
1058    unsigned int n;
1059    int changed = 0;
1060    n = (i->min - min) % step;
1061    if (n != 0 || i->openmin) {
1062        i->min += step - n;
1063        changed = 1;
1064    }
1065    n = (i->max - min) % step;
1066    if (n != 0 || i->openmax) {
1067        i->max -= n;
1068        changed = 1;
1069    }
1070    if (snd_interval_checkempty(i)) {
1071        i->empty = 1;
1072        return -EINVAL;
1073    }
1074    return changed;
1075}
1076
1077/* Info constraints helpers */
1078
1079/**
1080 * snd_pcm_hw_rule_add - add the hw-constraint rule
1081 * @runtime: the pcm runtime instance
1082 * @cond: condition bits
1083 * @var: the variable to evaluate
1084 * @func: the evaluation function
1085 * @private: the private data pointer passed to function
1086 * @dep: the dependent variables
1087 *
1088 * Returns zero if successful, or a negative error code on failure.
1089 */
1090int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1091            int var,
1092            snd_pcm_hw_rule_func_t func, void *private,
1093            int dep, ...)
1094{
1095    struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1096    struct snd_pcm_hw_rule *c;
1097    unsigned int k;
1098    va_list args;
1099    va_start(args, dep);
1100    if (constrs->rules_num >= constrs->rules_all) {
1101        struct snd_pcm_hw_rule *new;
1102        unsigned int new_rules = constrs->rules_all + 16;
1103        new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1104        if (!new) {
1105            va_end(args);
1106            return -ENOMEM;
1107        }
1108        if (constrs->rules) {
1109            memcpy(new, constrs->rules,
1110                   constrs->rules_num * sizeof(*c));
1111            kfree(constrs->rules);
1112        }
1113        constrs->rules = new;
1114        constrs->rules_all = new_rules;
1115    }
1116    c = &constrs->rules[constrs->rules_num];
1117    c->cond = cond;
1118    c->func = func;
1119    c->var = var;
1120    c->private = private;
1121    k = 0;
1122    while (1) {
1123        if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1124            va_end(args);
1125            return -EINVAL;
1126        }
1127        c->deps[k++] = dep;
1128        if (dep < 0)
1129            break;
1130        dep = va_arg(args, int);
1131    }
1132    constrs->rules_num++;
1133    va_end(args);
1134    return 0;
1135}
1136
1137EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1138
1139/**
1140 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1141 * @runtime: PCM runtime instance
1142 * @var: hw_params variable to apply the mask
1143 * @mask: the bitmap mask
1144 *
1145 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1146 */
1147int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1148                   u_int32_t mask)
1149{
1150    struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1151    struct snd_mask *maskp = constrs_mask(constrs, var);
1152    *maskp->bits &= mask;
1153    memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1154    if (*maskp->bits == 0)
1155        return -EINVAL;
1156    return 0;
1157}
1158
1159/**
1160 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1161 * @runtime: PCM runtime instance
1162 * @var: hw_params variable to apply the mask
1163 * @mask: the 64bit bitmap mask
1164 *
1165 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1166 */
1167int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1168                 u_int64_t mask)
1169{
1170    struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1171    struct snd_mask *maskp = constrs_mask(constrs, var);
1172    maskp->bits[0] &= (u_int32_t)mask;
1173    maskp->bits[1] &= (u_int32_t)(mask >> 32);
1174    memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1175    if (! maskp->bits[0] && ! maskp->bits[1])
1176        return -EINVAL;
1177    return 0;
1178}
1179
1180/**
1181 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1182 * @runtime: PCM runtime instance
1183 * @var: hw_params variable to apply the integer constraint
1184 *
1185 * Apply the constraint of integer to an interval parameter.
1186 */
1187int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1188{
1189    struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1190    return snd_interval_setinteger(constrs_interval(constrs, var));
1191}
1192
1193EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1194
1195/**
1196 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1197 * @runtime: PCM runtime instance
1198 * @var: hw_params variable to apply the range
1199 * @min: the minimal value
1200 * @max: the maximal value
1201 *
1202 * Apply the min/max range constraint to an interval parameter.
1203 */
1204int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1205                 unsigned int min, unsigned int max)
1206{
1207    struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1208    struct snd_interval t;
1209    t.min = min;
1210    t.max = max;
1211    t.openmin = t.openmax = 0;
1212    t.integer = 0;
1213    return snd_interval_refine(constrs_interval(constrs, var), &t);
1214}
1215
1216EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1217
1218static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1219                struct snd_pcm_hw_rule *rule)
1220{
1221    struct snd_pcm_hw_constraint_list *list = rule->private;
1222    return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1223}
1224
1225
1226/**
1227 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1228 * @runtime: PCM runtime instance
1229 * @cond: condition bits
1230 * @var: hw_params variable to apply the list constraint
1231 * @l: list
1232 *
1233 * Apply the list of constraints to an interval parameter.
1234 */
1235int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1236                   unsigned int cond,
1237                   snd_pcm_hw_param_t var,
1238                   struct snd_pcm_hw_constraint_list *l)
1239{
1240    return snd_pcm_hw_rule_add(runtime, cond, var,
1241                   snd_pcm_hw_rule_list, l,
1242                   var, -1);
1243}
1244
1245EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1246
1247static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1248                   struct snd_pcm_hw_rule *rule)
1249{
1250    struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1251    unsigned int num = 0, den = 0;
1252    int err;
1253    err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1254                  r->nrats, r->rats, &num, &den);
1255    if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1256        params->rate_num = num;
1257        params->rate_den = den;
1258    }
1259    return err;
1260}
1261
1262/**
1263 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1264 * @runtime: PCM runtime instance
1265 * @cond: condition bits
1266 * @var: hw_params variable to apply the ratnums constraint
1267 * @r: struct snd_ratnums constriants
1268 */
1269int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1270                  unsigned int cond,
1271                  snd_pcm_hw_param_t var,
1272                  struct snd_pcm_hw_constraint_ratnums *r)
1273{
1274    return snd_pcm_hw_rule_add(runtime, cond, var,
1275                   snd_pcm_hw_rule_ratnums, r,
1276                   var, -1);
1277}
1278
1279EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1280
1281static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1282                   struct snd_pcm_hw_rule *rule)
1283{
1284    struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1285    unsigned int num = 0, den = 0;
1286    int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1287                  r->nrats, r->rats, &num, &den);
1288    if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1289        params->rate_num = num;
1290        params->rate_den = den;
1291    }
1292    return err;
1293}
1294
1295/**
1296 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1297 * @runtime: PCM runtime instance
1298 * @cond: condition bits
1299 * @var: hw_params variable to apply the ratdens constraint
1300 * @r: struct snd_ratdens constriants
1301 */
1302int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1303                  unsigned int cond,
1304                  snd_pcm_hw_param_t var,
1305                  struct snd_pcm_hw_constraint_ratdens *r)
1306{
1307    return snd_pcm_hw_rule_add(runtime, cond, var,
1308                   snd_pcm_hw_rule_ratdens, r,
1309                   var, -1);
1310}
1311
1312EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1313
1314static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1315                  struct snd_pcm_hw_rule *rule)
1316{
1317    unsigned int l = (unsigned long) rule->private;
1318    int width = l & 0xffff;
1319    unsigned int msbits = l >> 16;
1320    struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1321    if (snd_interval_single(i) && snd_interval_value(i) == width)
1322        params->msbits = msbits;
1323    return 0;
1324}
1325
1326/**
1327 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1328 * @runtime: PCM runtime instance
1329 * @cond: condition bits
1330 * @width: sample bits width
1331 * @msbits: msbits width
1332 */
1333int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1334                 unsigned int cond,
1335                 unsigned int width,
1336                 unsigned int msbits)
1337{
1338    unsigned long l = (msbits << 16) | width;
1339    return snd_pcm_hw_rule_add(runtime, cond, -1,
1340                    snd_pcm_hw_rule_msbits,
1341                    (void*) l,
1342                    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1343}
1344
1345EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1346
1347static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1348                struct snd_pcm_hw_rule *rule)
1349{
1350    unsigned long step = (unsigned long) rule->private;
1351    return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1352}
1353
1354/**
1355 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1356 * @runtime: PCM runtime instance
1357 * @cond: condition bits
1358 * @var: hw_params variable to apply the step constraint
1359 * @step: step size
1360 */
1361int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1362                   unsigned int cond,
1363                   snd_pcm_hw_param_t var,
1364                   unsigned long step)
1365{
1366    return snd_pcm_hw_rule_add(runtime, cond, var,
1367                   snd_pcm_hw_rule_step, (void *) step,
1368                   var, -1);
1369}
1370
1371EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1372
1373static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1374{
1375    static unsigned int pow2_sizes[] = {
1376        1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1377        1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1378        1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1379        1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1380    };
1381    return snd_interval_list(hw_param_interval(params, rule->var),
1382                 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1383}
1384
1385/**
1386 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1387 * @runtime: PCM runtime instance
1388 * @cond: condition bits
1389 * @var: hw_params variable to apply the power-of-2 constraint
1390 */
1391int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1392                   unsigned int cond,
1393                   snd_pcm_hw_param_t var)
1394{
1395    return snd_pcm_hw_rule_add(runtime, cond, var,
1396                   snd_pcm_hw_rule_pow2, NULL,
1397                   var, -1);
1398}
1399
1400EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1401
1402static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1403                  snd_pcm_hw_param_t var)
1404{
1405    if (hw_is_mask(var)) {
1406        snd_mask_any(hw_param_mask(params, var));
1407        params->cmask |= 1 << var;
1408        params->rmask |= 1 << var;
1409        return;
1410    }
1411    if (hw_is_interval(var)) {
1412        snd_interval_any(hw_param_interval(params, var));
1413        params->cmask |= 1 << var;
1414        params->rmask |= 1 << var;
1415        return;
1416    }
1417    snd_BUG();
1418}
1419
1420void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1421{
1422    unsigned int k;
1423    memset(params, 0, sizeof(*params));
1424    for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1425        _snd_pcm_hw_param_any(params, k);
1426    for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1427        _snd_pcm_hw_param_any(params, k);
1428    params->info = ~0U;
1429}
1430
1431EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1432
1433/**
1434 * snd_pcm_hw_param_value - return @params field @var value
1435 * @params: the hw_params instance
1436 * @var: parameter to retrieve
1437 * @dir: pointer to the direction (-1,0,1) or %NULL
1438 *
1439 * Return the value for field @var if it's fixed in configuration space
1440 * defined by @params. Return -%EINVAL otherwise.
1441 */
1442int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1443               snd_pcm_hw_param_t var, int *dir)
1444{
1445    if (hw_is_mask(var)) {
1446        const struct snd_mask *mask = hw_param_mask_c(params, var);
1447        if (!snd_mask_single(mask))
1448            return -EINVAL;
1449        if (dir)
1450            *dir = 0;
1451        return snd_mask_value(mask);
1452    }
1453    if (hw_is_interval(var)) {
1454        const struct snd_interval *i = hw_param_interval_c(params, var);
1455        if (!snd_interval_single(i))
1456            return -EINVAL;
1457        if (dir)
1458            *dir = i->openmin;
1459        return snd_interval_value(i);
1460    }
1461    return -EINVAL;
1462}
1463
1464EXPORT_SYMBOL(snd_pcm_hw_param_value);
1465
1466void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1467                snd_pcm_hw_param_t var)
1468{
1469    if (hw_is_mask(var)) {
1470        snd_mask_none(hw_param_mask(params, var));
1471        params->cmask |= 1 << var;
1472        params->rmask |= 1 << var;
1473    } else if (hw_is_interval(var)) {
1474        snd_interval_none(hw_param_interval(params, var));
1475        params->cmask |= 1 << var;
1476        params->rmask |= 1 << var;
1477    } else {
1478        snd_BUG();
1479    }
1480}
1481
1482EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1483
1484static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1485                   snd_pcm_hw_param_t var)
1486{
1487    int changed;
1488    if (hw_is_mask(var))
1489        changed = snd_mask_refine_first(hw_param_mask(params, var));
1490    else if (hw_is_interval(var))
1491        changed = snd_interval_refine_first(hw_param_interval(params, var));
1492    else
1493        return -EINVAL;
1494    if (changed) {
1495        params->cmask |= 1 << var;
1496        params->rmask |= 1 << var;
1497    }
1498    return changed;
1499}
1500
1501
1502/**
1503 * snd_pcm_hw_param_first - refine config space and return minimum value
1504 * @pcm: PCM instance
1505 * @params: the hw_params instance
1506 * @var: parameter to retrieve
1507 * @dir: pointer to the direction (-1,0,1) or %NULL
1508 *
1509 * Inside configuration space defined by @params remove from @var all
1510 * values > minimum. Reduce configuration space accordingly.
1511 * Return the minimum.
1512 */
1513int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1514               struct snd_pcm_hw_params *params,
1515               snd_pcm_hw_param_t var, int *dir)
1516{
1517    int changed = _snd_pcm_hw_param_first(params, var);
1518    if (changed < 0)
1519        return changed;
1520    if (params->rmask) {
1521        int err = snd_pcm_hw_refine(pcm, params);
1522        if (snd_BUG_ON(err < 0))
1523            return err;
1524    }
1525    return snd_pcm_hw_param_value(params, var, dir);
1526}
1527
1528EXPORT_SYMBOL(snd_pcm_hw_param_first);
1529
1530static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1531                  snd_pcm_hw_param_t var)
1532{
1533    int changed;
1534    if (hw_is_mask(var))
1535        changed = snd_mask_refine_last(hw_param_mask(params, var));
1536    else if (hw_is_interval(var))
1537        changed = snd_interval_refine_last(hw_param_interval(params, var));
1538    else
1539        return -EINVAL;
1540    if (changed) {
1541        params->cmask |= 1 << var;
1542        params->rmask |= 1 << var;
1543    }
1544    return changed;
1545}
1546
1547
1548/**
1549 * snd_pcm_hw_param_last - refine config space and return maximum value
1550 * @pcm: PCM instance
1551 * @params: the hw_params instance
1552 * @var: parameter to retrieve
1553 * @dir: pointer to the direction (-1,0,1) or %NULL
1554 *
1555 * Inside configuration space defined by @params remove from @var all
1556 * values < maximum. Reduce configuration space accordingly.
1557 * Return the maximum.
1558 */
1559int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1560              struct snd_pcm_hw_params *params,
1561              snd_pcm_hw_param_t var, int *dir)
1562{
1563    int changed = _snd_pcm_hw_param_last(params, var);
1564    if (changed < 0)
1565        return changed;
1566    if (params->rmask) {
1567        int err = snd_pcm_hw_refine(pcm, params);
1568        if (snd_BUG_ON(err < 0))
1569            return err;
1570    }
1571    return snd_pcm_hw_param_value(params, var, dir);
1572}
1573
1574EXPORT_SYMBOL(snd_pcm_hw_param_last);
1575
1576/**
1577 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1578 * @pcm: PCM instance
1579 * @params: the hw_params instance
1580 *
1581 * Choose one configuration from configuration space defined by @params.
1582 * The configuration chosen is that obtained fixing in this order:
1583 * first access, first format, first subformat, min channels,
1584 * min rate, min period time, max buffer size, min tick time
1585 */
1586int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1587                 struct snd_pcm_hw_params *params)
1588{
1589    static int vars[] = {
1590        SNDRV_PCM_HW_PARAM_ACCESS,
1591        SNDRV_PCM_HW_PARAM_FORMAT,
1592        SNDRV_PCM_HW_PARAM_SUBFORMAT,
1593        SNDRV_PCM_HW_PARAM_CHANNELS,
1594        SNDRV_PCM_HW_PARAM_RATE,
1595        SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1596        SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1597        SNDRV_PCM_HW_PARAM_TICK_TIME,
1598        -1
1599    };
1600    int err, *v;
1601
1602    for (v = vars; *v != -1; v++) {
1603        if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1604            err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1605        else
1606            err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1607        if (snd_BUG_ON(err < 0))
1608            return err;
1609    }
1610    return 0;
1611}
1612
1613static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1614                   void *arg)
1615{
1616    struct snd_pcm_runtime *runtime = substream->runtime;
1617    unsigned long flags;
1618    snd_pcm_stream_lock_irqsave(substream, flags);
1619    if (snd_pcm_running(substream) &&
1620        snd_pcm_update_hw_ptr(substream) >= 0)
1621        runtime->status->hw_ptr %= runtime->buffer_size;
1622    else
1623        runtime->status->hw_ptr = 0;
1624    snd_pcm_stream_unlock_irqrestore(substream, flags);
1625    return 0;
1626}
1627
1628static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1629                      void *arg)
1630{
1631    struct snd_pcm_channel_info *info = arg;
1632    struct snd_pcm_runtime *runtime = substream->runtime;
1633    int width;
1634    if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1635        info->offset = -1;
1636        return 0;
1637    }
1638    width = snd_pcm_format_physical_width(runtime->format);
1639    if (width < 0)
1640        return width;
1641    info->offset = 0;
1642    switch (runtime->access) {
1643    case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1644    case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1645        info->first = info->channel * width;
1646        info->step = runtime->channels * width;
1647        break;
1648    case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1649    case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1650    {
1651        size_t size = runtime->dma_bytes / runtime->channels;
1652        info->first = info->channel * size * 8;
1653        info->step = width;
1654        break;
1655    }
1656    default:
1657        snd_BUG();
1658        break;
1659    }
1660    return 0;
1661}
1662
1663static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1664                       void *arg)
1665{
1666    struct snd_pcm_hw_params *params = arg;
1667    snd_pcm_format_t format;
1668    int channels, width;
1669
1670    params->fifo_size = substream->runtime->hw.fifo_size;
1671    if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1672        format = params_format(params);
1673        channels = params_channels(params);
1674        width = snd_pcm_format_physical_width(format);
1675        params->fifo_size /= width * channels;
1676    }
1677    return 0;
1678}
1679
1680/**
1681 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1682 * @substream: the pcm substream instance
1683 * @cmd: ioctl command
1684 * @arg: ioctl argument
1685 *
1686 * Processes the generic ioctl commands for PCM.
1687 * Can be passed as the ioctl callback for PCM ops.
1688 *
1689 * Returns zero if successful, or a negative error code on failure.
1690 */
1691int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1692              unsigned int cmd, void *arg)
1693{
1694    switch (cmd) {
1695    case SNDRV_PCM_IOCTL1_INFO:
1696        return 0;
1697    case SNDRV_PCM_IOCTL1_RESET:
1698        return snd_pcm_lib_ioctl_reset(substream, arg);
1699    case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1700        return snd_pcm_lib_ioctl_channel_info(substream, arg);
1701    case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1702        return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1703    }
1704    return -ENXIO;
1705}
1706
1707EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1708
1709/**
1710 * snd_pcm_period_elapsed - update the pcm status for the next period
1711 * @substream: the pcm substream instance
1712 *
1713 * This function is called from the interrupt handler when the
1714 * PCM has processed the period size. It will update the current
1715 * pointer, wake up sleepers, etc.
1716 *
1717 * Even if more than one periods have elapsed since the last call, you
1718 * have to call this only once.
1719 */
1720void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1721{
1722    struct snd_pcm_runtime *runtime;
1723    unsigned long flags;
1724
1725    if (PCM_RUNTIME_CHECK(substream))
1726        return;
1727    runtime = substream->runtime;
1728
1729    if (runtime->transfer_ack_begin)
1730        runtime->transfer_ack_begin(substream);
1731
1732    snd_pcm_stream_lock_irqsave(substream, flags);
1733    if (!snd_pcm_running(substream) ||
1734        snd_pcm_update_hw_ptr0(substream, 1) < 0)
1735        goto _end;
1736
1737    if (substream->timer_running)
1738        snd_timer_interrupt(substream->timer, 1);
1739 _end:
1740    snd_pcm_stream_unlock_irqrestore(substream, flags);
1741    if (runtime->transfer_ack_end)
1742        runtime->transfer_ack_end(substream);
1743    kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1744}
1745
1746EXPORT_SYMBOL(snd_pcm_period_elapsed);
1747
1748/*
1749 * Wait until avail_min data becomes available
1750 * Returns a negative error code if any error occurs during operation.
1751 * The available space is stored on availp. When err = 0 and avail = 0
1752 * on the capture stream, it indicates the stream is in DRAINING state.
1753 */
1754static int wait_for_avail(struct snd_pcm_substream *substream,
1755                  snd_pcm_uframes_t *availp)
1756{
1757    struct snd_pcm_runtime *runtime = substream->runtime;
1758    int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1759    wait_queue_t wait;
1760    int err = 0;
1761    snd_pcm_uframes_t avail = 0;
1762    long wait_time, tout;
1763
1764    init_waitqueue_entry(&wait, current);
1765    set_current_state(TASK_INTERRUPTIBLE);
1766    add_wait_queue(&runtime->tsleep, &wait);
1767
1768    if (runtime->no_period_wakeup)
1769        wait_time = MAX_SCHEDULE_TIMEOUT;
1770    else {
1771        wait_time = 10;
1772        if (runtime->rate) {
1773            long t = runtime->period_size * 2 / runtime->rate;
1774            wait_time = max(t, wait_time);
1775        }
1776        wait_time = msecs_to_jiffies(wait_time * 1000);
1777    }
1778
1779    for (;;) {
1780        if (signal_pending(current)) {
1781            err = -ERESTARTSYS;
1782            break;
1783        }
1784
1785        /*
1786         * We need to check if space became available already
1787         * (and thus the wakeup happened already) first to close
1788         * the race of space already having become available.
1789         * This check must happen after been added to the waitqueue
1790         * and having current state be INTERRUPTIBLE.
1791         */
1792        if (is_playback)
1793            avail = snd_pcm_playback_avail(runtime);
1794        else
1795            avail = snd_pcm_capture_avail(runtime);
1796        if (avail >= runtime->twake)
1797            break;
1798        snd_pcm_stream_unlock_irq(substream);
1799
1800        tout = schedule_timeout(wait_time);
1801
1802        snd_pcm_stream_lock_irq(substream);
1803        set_current_state(TASK_INTERRUPTIBLE);
1804        switch (runtime->status->state) {
1805        case SNDRV_PCM_STATE_SUSPENDED:
1806            err = -ESTRPIPE;
1807            goto _endloop;
1808        case SNDRV_PCM_STATE_XRUN:
1809            err = -EPIPE;
1810            goto _endloop;
1811        case SNDRV_PCM_STATE_DRAINING:
1812            if (is_playback)
1813                err = -EPIPE;
1814            else
1815                avail = 0; /* indicate draining */
1816            goto _endloop;
1817        case SNDRV_PCM_STATE_OPEN:
1818        case SNDRV_PCM_STATE_SETUP:
1819        case SNDRV_PCM_STATE_DISCONNECTED:
1820            err = -EBADFD;
1821            goto _endloop;
1822        }
1823        if (!tout) {
1824            snd_printd("%s write error (DMA or IRQ trouble?)\n",
1825                   is_playback ? "playback" : "capture");
1826            err = -EIO;
1827            break;
1828        }
1829    }
1830 _endloop:
1831    set_current_state(TASK_RUNNING);
1832    remove_wait_queue(&runtime->tsleep, &wait);
1833    *availp = avail;
1834    return err;
1835}
1836    
1837static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1838                      unsigned int hwoff,
1839                      unsigned long data, unsigned int off,
1840                      snd_pcm_uframes_t frames)
1841{
1842    struct snd_pcm_runtime *runtime = substream->runtime;
1843    int err;
1844    char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1845    if (substream->ops->copy) {
1846        if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1847            return err;
1848    } else {
1849        char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1850        if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1851            return -EFAULT;
1852    }
1853    return 0;
1854}
1855 
1856typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1857              unsigned long data, unsigned int off,
1858              snd_pcm_uframes_t size);
1859
1860static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1861                        unsigned long data,
1862                        snd_pcm_uframes_t size,
1863                        int nonblock,
1864                        transfer_f transfer)
1865{
1866    struct snd_pcm_runtime *runtime = substream->runtime;
1867    snd_pcm_uframes_t xfer = 0;
1868    snd_pcm_uframes_t offset = 0;
1869    int err = 0;
1870
1871    if (size == 0)
1872        return 0;
1873
1874    snd_pcm_stream_lock_irq(substream);
1875    switch (runtime->status->state) {
1876    case SNDRV_PCM_STATE_PREPARED:
1877    case SNDRV_PCM_STATE_RUNNING:
1878    case SNDRV_PCM_STATE_PAUSED:
1879        break;
1880    case SNDRV_PCM_STATE_XRUN:
1881        err = -EPIPE;
1882        goto _end_unlock;
1883    case SNDRV_PCM_STATE_SUSPENDED:
1884        err = -ESTRPIPE;
1885        goto _end_unlock;
1886    default:
1887        err = -EBADFD;
1888        goto _end_unlock;
1889    }
1890
1891    runtime->twake = runtime->control->avail_min ? : 1;
1892    while (size > 0) {
1893        snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1894        snd_pcm_uframes_t avail;
1895        snd_pcm_uframes_t cont;
1896        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1897            snd_pcm_update_hw_ptr(substream);
1898        avail = snd_pcm_playback_avail(runtime);
1899        if (!avail) {
1900            if (nonblock) {
1901                err = -EAGAIN;
1902                goto _end_unlock;
1903            }
1904            runtime->twake = min_t(snd_pcm_uframes_t, size,
1905                    runtime->control->avail_min ? : 1);
1906            err = wait_for_avail(substream, &avail);
1907            if (err < 0)
1908                goto _end_unlock;
1909        }
1910        frames = size > avail ? avail : size;
1911        cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1912        if (frames > cont)
1913            frames = cont;
1914        if (snd_BUG_ON(!frames)) {
1915            runtime->twake = 0;
1916            snd_pcm_stream_unlock_irq(substream);
1917            return -EINVAL;
1918        }
1919        appl_ptr = runtime->control->appl_ptr;
1920        appl_ofs = appl_ptr % runtime->buffer_size;
1921        snd_pcm_stream_unlock_irq(substream);
1922        err = transfer(substream, appl_ofs, data, offset, frames);
1923        snd_pcm_stream_lock_irq(substream);
1924        if (err < 0)
1925            goto _end_unlock;
1926        switch (runtime->status->state) {
1927        case SNDRV_PCM_STATE_XRUN:
1928            err = -EPIPE;
1929            goto _end_unlock;
1930        case SNDRV_PCM_STATE_SUSPENDED:
1931            err = -ESTRPIPE;
1932            goto _end_unlock;
1933        default:
1934            break;
1935        }
1936        appl_ptr += frames;
1937        if (appl_ptr >= runtime->boundary)
1938            appl_ptr -= runtime->boundary;
1939        runtime->control->appl_ptr = appl_ptr;
1940        if (substream->ops->ack)
1941            substream->ops->ack(substream);
1942
1943        offset += frames;
1944        size -= frames;
1945        xfer += frames;
1946        if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1947            snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1948            err = snd_pcm_start(substream);
1949            if (err < 0)
1950                goto _end_unlock;
1951        }
1952    }
1953 _end_unlock:
1954    runtime->twake = 0;
1955    if (xfer > 0 && err >= 0)
1956        snd_pcm_update_state(substream, runtime);
1957    snd_pcm_stream_unlock_irq(substream);
1958    return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1959}
1960
1961/* sanity-check for read/write methods */
1962static int pcm_sanity_check(struct snd_pcm_substream *substream)
1963{
1964    struct snd_pcm_runtime *runtime;
1965    if (PCM_RUNTIME_CHECK(substream))
1966        return -ENXIO;
1967    runtime = substream->runtime;
1968    if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1969        return -EINVAL;
1970    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1971        return -EBADFD;
1972    return 0;
1973}
1974
1975snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1976{
1977    struct snd_pcm_runtime *runtime;
1978    int nonblock;
1979    int err;
1980
1981    err = pcm_sanity_check(substream);
1982    if (err < 0)
1983        return err;
1984    runtime = substream->runtime;
1985    nonblock = !!(substream->f_flags & O_NONBLOCK);
1986
1987    if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1988        runtime->channels > 1)
1989        return -EINVAL;
1990    return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1991                  snd_pcm_lib_write_transfer);
1992}
1993
1994EXPORT_SYMBOL(snd_pcm_lib_write);
1995
1996static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1997                       unsigned int hwoff,
1998                       unsigned long data, unsigned int off,
1999                       snd_pcm_uframes_t frames)
2000{
2001    struct snd_pcm_runtime *runtime = substream->runtime;
2002    int err;
2003    void __user **bufs = (void __user **)data;
2004    int channels = runtime->channels;
2005    int c;
2006    if (substream->ops->copy) {
2007        if (snd_BUG_ON(!substream->ops->silence))
2008            return -EINVAL;
2009        for (c = 0; c < channels; ++c, ++bufs) {
2010            if (*bufs == NULL) {
2011                if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2012                    return err;
2013            } else {
2014                char __user *buf = *bufs + samples_to_bytes(runtime, off);
2015                if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2016                    return err;
2017            }
2018        }
2019    } else {
2020        /* default transfer behaviour */
2021        size_t dma_csize = runtime->dma_bytes / channels;
2022        for (c = 0; c < channels; ++c, ++bufs) {
2023            char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2024            if (*bufs == NULL) {
2025                snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2026            } else {
2027                char __user *buf = *bufs + samples_to_bytes(runtime, off);
2028                if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2029                    return -EFAULT;
2030            }
2031        }
2032    }
2033    return 0;
2034}
2035 
2036snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2037                     void __user **bufs,
2038                     snd_pcm_uframes_t frames)
2039{
2040    struct snd_pcm_runtime *runtime;
2041    int nonblock;
2042    int err;
2043
2044    err = pcm_sanity_check(substream);
2045    if (err < 0)
2046        return err;
2047    runtime = substream->runtime;
2048    nonblock = !!(substream->f_flags & O_NONBLOCK);
2049
2050    if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2051        return -EINVAL;
2052    return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2053                  nonblock, snd_pcm_lib_writev_transfer);
2054}
2055
2056EXPORT_SYMBOL(snd_pcm_lib_writev);
2057
2058static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2059                     unsigned int hwoff,
2060                     unsigned long data, unsigned int off,
2061                     snd_pcm_uframes_t frames)
2062{
2063    struct snd_pcm_runtime *runtime = substream->runtime;
2064    int err;
2065    char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2066    if (substream->ops->copy) {
2067        if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2068            return err;
2069    } else {
2070        char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2071        if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2072            return -EFAULT;
2073    }
2074    return 0;
2075}
2076
2077static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2078                       unsigned long data,
2079                       snd_pcm_uframes_t size,
2080                       int nonblock,
2081                       transfer_f transfer)
2082{
2083    struct snd_pcm_runtime *runtime = substream->runtime;
2084    snd_pcm_uframes_t xfer = 0;
2085    snd_pcm_uframes_t offset = 0;
2086    int err = 0;
2087
2088    if (size == 0)
2089        return 0;
2090
2091    snd_pcm_stream_lock_irq(substream);
2092    switch (runtime->status->state) {
2093    case SNDRV_PCM_STATE_PREPARED:
2094        if (size >= runtime->start_threshold) {
2095            err = snd_pcm_start(substream);
2096            if (err < 0)
2097                goto _end_unlock;
2098        }
2099        break;
2100    case SNDRV_PCM_STATE_DRAINING:
2101    case SNDRV_PCM_STATE_RUNNING:
2102    case SNDRV_PCM_STATE_PAUSED:
2103        break;
2104    case SNDRV_PCM_STATE_XRUN:
2105        err = -EPIPE;
2106        goto _end_unlock;
2107    case SNDRV_PCM_STATE_SUSPENDED:
2108        err = -ESTRPIPE;
2109        goto _end_unlock;
2110    default:
2111        err = -EBADFD;
2112        goto _end_unlock;
2113    }
2114
2115    runtime->twake = runtime->control->avail_min ? : 1;
2116    while (size > 0) {
2117        snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2118        snd_pcm_uframes_t avail;
2119        snd_pcm_uframes_t cont;
2120        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2121            snd_pcm_update_hw_ptr(substream);
2122        avail = snd_pcm_capture_avail(runtime);
2123        if (!avail) {
2124            if (runtime->status->state ==
2125                SNDRV_PCM_STATE_DRAINING) {
2126                snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2127                goto _end_unlock;
2128            }
2129            if (nonblock) {
2130                err = -EAGAIN;
2131                goto _end_unlock;
2132            }
2133            runtime->twake = min_t(snd_pcm_uframes_t, size,
2134                    runtime->control->avail_min ? : 1);
2135            err = wait_for_avail(substream, &avail);
2136            if (err < 0)
2137                goto _end_unlock;
2138            if (!avail)
2139                continue; /* draining */
2140        }
2141        frames = size > avail ? avail : size;
2142        cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2143        if (frames > cont)
2144            frames = cont;
2145        if (snd_BUG_ON(!frames)) {
2146            runtime->twake = 0;
2147            snd_pcm_stream_unlock_irq(substream);
2148            return -EINVAL;
2149        }
2150        appl_ptr = runtime->control->appl_ptr;
2151        appl_ofs = appl_ptr % runtime->buffer_size;
2152        snd_pcm_stream_unlock_irq(substream);
2153        err = transfer(substream, appl_ofs, data, offset, frames);
2154        snd_pcm_stream_lock_irq(substream);
2155        if (err < 0)
2156            goto _end_unlock;
2157        switch (runtime->status->state) {
2158        case SNDRV_PCM_STATE_XRUN:
2159            err = -EPIPE;
2160            goto _end_unlock;
2161        case SNDRV_PCM_STATE_SUSPENDED:
2162            err = -ESTRPIPE;
2163            goto _end_unlock;
2164        default:
2165            break;
2166        }
2167        appl_ptr += frames;
2168        if (appl_ptr >= runtime->boundary)
2169            appl_ptr -= runtime->boundary;
2170        runtime->control->appl_ptr = appl_ptr;
2171        if (substream->ops->ack)
2172            substream->ops->ack(substream);
2173
2174        offset += frames;
2175        size -= frames;
2176        xfer += frames;
2177    }
2178 _end_unlock:
2179    runtime->twake = 0;
2180    if (xfer > 0 && err >= 0)
2181        snd_pcm_update_state(substream, runtime);
2182    snd_pcm_stream_unlock_irq(substream);
2183    return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2184}
2185
2186snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2187{
2188    struct snd_pcm_runtime *runtime;
2189    int nonblock;
2190    int err;
2191    
2192    err = pcm_sanity_check(substream);
2193    if (err < 0)
2194        return err;
2195    runtime = substream->runtime;
2196    nonblock = !!(substream->f_flags & O_NONBLOCK);
2197    if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2198        return -EINVAL;
2199    return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2200}
2201
2202EXPORT_SYMBOL(snd_pcm_lib_read);
2203
2204static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2205                      unsigned int hwoff,
2206                      unsigned long data, unsigned int off,
2207                      snd_pcm_uframes_t frames)
2208{
2209    struct snd_pcm_runtime *runtime = substream->runtime;
2210    int err;
2211    void __user **bufs = (void __user **)data;
2212    int channels = runtime->channels;
2213    int c;
2214    if (substream->ops->copy) {
2215        for (c = 0; c < channels; ++c, ++bufs) {
2216            char __user *buf;
2217            if (*bufs == NULL)
2218                continue;
2219            buf = *bufs + samples_to_bytes(runtime, off);
2220            if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2221                return err;
2222        }
2223    } else {
2224        snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2225        for (c = 0; c < channels; ++c, ++bufs) {
2226            char *hwbuf;
2227            char __user *buf;
2228            if (*bufs == NULL)
2229                continue;
2230
2231            hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2232            buf = *bufs + samples_to_bytes(runtime, off);
2233            if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2234                return -EFAULT;
2235        }
2236    }
2237    return 0;
2238}
2239 
2240snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2241                    void __user **bufs,
2242                    snd_pcm_uframes_t frames)
2243{
2244    struct snd_pcm_runtime *runtime;
2245    int nonblock;
2246    int err;
2247
2248    err = pcm_sanity_check(substream);
2249    if (err < 0)
2250        return err;
2251    runtime = substream->runtime;
2252    if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2253        return -EBADFD;
2254
2255    nonblock = !!(substream->f_flags & O_NONBLOCK);
2256    if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2257        return -EINVAL;
2258    return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2259}
2260
2261EXPORT_SYMBOL(snd_pcm_lib_readv);
2262

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