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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Digital Audio (PCM) abstract layer
  4 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  5 */
  6
  7#include <linux/time.h>
  8#include <linux/gcd.h>
  9#include <sound/core.h>
 10#include <sound/pcm.h>
 11#include <sound/timer.h>
 12
 13#include "pcm_local.h"
 14
 15/*
 16 *  Timer functions
 17 */
 18
 19void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream)
 20{
 21	unsigned long rate, mult, fsize, l, post;
 22	struct snd_pcm_runtime *runtime = substream->runtime;
 23
 24	mult = 1000000000;
 25	rate = runtime->rate;
 26	if (snd_BUG_ON(!rate))
 27		return;
 28	l = gcd(mult, rate);
 29	mult /= l;
 30	rate /= l;
 31	fsize = runtime->period_size;
 32	if (snd_BUG_ON(!fsize))
 33		return;
 34	l = gcd(rate, fsize);
 35	rate /= l;
 36	fsize /= l;
 37	post = 1;
 38	while ((mult * fsize) / fsize != mult) {
 39		mult /= 2;
 40		post *= 2;
 41	}
 42	if (rate == 0) {
 43		pcm_err(substream->pcm,
 44			"pcm timer resolution out of range (rate = %u, period_size = %lu)\n",
 45			runtime->rate, runtime->period_size);
 46		runtime->timer_resolution = -1;
 47		return;
 48	}
 49	runtime->timer_resolution = (mult * fsize / rate) * post;
 50}
 51
 52static unsigned long snd_pcm_timer_resolution(struct snd_timer * timer)
 53{
 54	struct snd_pcm_substream *substream;
 55
 56	substream = timer->private_data;
 57	return substream->runtime ? substream->runtime->timer_resolution : 0;
 58}
 59
 60static int snd_pcm_timer_start(struct snd_timer * timer)
 61{
 62	struct snd_pcm_substream *substream;
 63
 64	substream = snd_timer_chip(timer);
 65	substream->timer_running = 1;
 66	return 0;
 67}
 68
 69static int snd_pcm_timer_stop(struct snd_timer * timer)
 70{
 71	struct snd_pcm_substream *substream;
 72
 73	substream = snd_timer_chip(timer);
 74	substream->timer_running = 0;
 75	return 0;
 76}
 77
 78static struct snd_timer_hardware snd_pcm_timer =
 79{
 80	.flags =	SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_SLAVE,
 81	.resolution =	0,
 82	.ticks =	1,
 83	.c_resolution =	snd_pcm_timer_resolution,
 84	.start =	snd_pcm_timer_start,
 85	.stop =		snd_pcm_timer_stop,
 86};
 87
 88/*
 89 *  Init functions
 90 */
 91
 92static void snd_pcm_timer_free(struct snd_timer *timer)
 93{
 94	struct snd_pcm_substream *substream = timer->private_data;
 95	substream->timer = NULL;
 96}
 97
 98void snd_pcm_timer_init(struct snd_pcm_substream *substream)
 99{
100	struct snd_timer_id tid;
101	struct snd_timer *timer;
102
103	tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
104	tid.dev_class = SNDRV_TIMER_CLASS_PCM;
105	tid.card = substream->pcm->card->number;
106	tid.device = substream->pcm->device;
107	tid.subdevice = (substream->number << 1) | (substream->stream & 1);
108	if (snd_timer_new(substream->pcm->card, "PCM", &tid, &timer) < 0)
109		return;
110	sprintf(timer->name, "PCM %s %i-%i-%i",
111			substream->stream == SNDRV_PCM_STREAM_CAPTURE ?
112				"capture" : "playback",
113			tid.card, tid.device, tid.subdevice);
114	timer->hw = snd_pcm_timer;
115	if (snd_device_register(timer->card, timer) < 0) {
116		snd_device_free(timer->card, timer);
117		return;
118	}
119	timer->private_data = substream;
120	timer->private_free = snd_pcm_timer_free;
121	substream->timer = timer;
122}
123
124void snd_pcm_timer_done(struct snd_pcm_substream *substream)
125{
126	if (substream->timer) {
127		snd_device_free(substream->pcm->card, substream->timer);
128		substream->timer = NULL;
129	}
130}
v4.17
 
  1/*
  2 *  Digital Audio (PCM) abstract layer
  3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  4 *
  5 *
  6 *   This program is free software; you can redistribute it and/or modify
  7 *   it under the terms of the GNU General Public License as published by
  8 *   the Free Software Foundation; either version 2 of the License, or
  9 *   (at your option) any later version.
 10 *
 11 *   This program is distributed in the hope that it will be useful,
 12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 *   GNU General Public License for more details.
 15 *
 16 *   You should have received a copy of the GNU General Public License
 17 *   along with this program; if not, write to the Free Software
 18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 19 *
 20 */
 21
 22#include <linux/time.h>
 23#include <linux/gcd.h>
 24#include <sound/core.h>
 25#include <sound/pcm.h>
 26#include <sound/timer.h>
 27
 28#include "pcm_local.h"
 29
 30/*
 31 *  Timer functions
 32 */
 33
 34void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream)
 35{
 36	unsigned long rate, mult, fsize, l, post;
 37	struct snd_pcm_runtime *runtime = substream->runtime;
 38
 39	mult = 1000000000;
 40	rate = runtime->rate;
 41	if (snd_BUG_ON(!rate))
 42		return;
 43	l = gcd(mult, rate);
 44	mult /= l;
 45	rate /= l;
 46	fsize = runtime->period_size;
 47	if (snd_BUG_ON(!fsize))
 48		return;
 49	l = gcd(rate, fsize);
 50	rate /= l;
 51	fsize /= l;
 52	post = 1;
 53	while ((mult * fsize) / fsize != mult) {
 54		mult /= 2;
 55		post *= 2;
 56	}
 57	if (rate == 0) {
 58		pcm_err(substream->pcm,
 59			"pcm timer resolution out of range (rate = %u, period_size = %lu)\n",
 60			runtime->rate, runtime->period_size);
 61		runtime->timer_resolution = -1;
 62		return;
 63	}
 64	runtime->timer_resolution = (mult * fsize / rate) * post;
 65}
 66
 67static unsigned long snd_pcm_timer_resolution(struct snd_timer * timer)
 68{
 69	struct snd_pcm_substream *substream;
 70
 71	substream = timer->private_data;
 72	return substream->runtime ? substream->runtime->timer_resolution : 0;
 73}
 74
 75static int snd_pcm_timer_start(struct snd_timer * timer)
 76{
 77	struct snd_pcm_substream *substream;
 78
 79	substream = snd_timer_chip(timer);
 80	substream->timer_running = 1;
 81	return 0;
 82}
 83
 84static int snd_pcm_timer_stop(struct snd_timer * timer)
 85{
 86	struct snd_pcm_substream *substream;
 87
 88	substream = snd_timer_chip(timer);
 89	substream->timer_running = 0;
 90	return 0;
 91}
 92
 93static struct snd_timer_hardware snd_pcm_timer =
 94{
 95	.flags =	SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_SLAVE,
 96	.resolution =	0,
 97	.ticks =	1,
 98	.c_resolution =	snd_pcm_timer_resolution,
 99	.start =	snd_pcm_timer_start,
100	.stop =		snd_pcm_timer_stop,
101};
102
103/*
104 *  Init functions
105 */
106
107static void snd_pcm_timer_free(struct snd_timer *timer)
108{
109	struct snd_pcm_substream *substream = timer->private_data;
110	substream->timer = NULL;
111}
112
113void snd_pcm_timer_init(struct snd_pcm_substream *substream)
114{
115	struct snd_timer_id tid;
116	struct snd_timer *timer;
117
118	tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
119	tid.dev_class = SNDRV_TIMER_CLASS_PCM;
120	tid.card = substream->pcm->card->number;
121	tid.device = substream->pcm->device;
122	tid.subdevice = (substream->number << 1) | (substream->stream & 1);
123	if (snd_timer_new(substream->pcm->card, "PCM", &tid, &timer) < 0)
124		return;
125	sprintf(timer->name, "PCM %s %i-%i-%i",
126			substream->stream == SNDRV_PCM_STREAM_CAPTURE ?
127				"capture" : "playback",
128			tid.card, tid.device, tid.subdevice);
129	timer->hw = snd_pcm_timer;
130	if (snd_device_register(timer->card, timer) < 0) {
131		snd_device_free(timer->card, timer);
132		return;
133	}
134	timer->private_data = substream;
135	timer->private_free = snd_pcm_timer_free;
136	substream->timer = timer;
137}
138
139void snd_pcm_timer_done(struct snd_pcm_substream *substream)
140{
141	if (substream->timer) {
142		snd_device_free(substream->pcm->card, substream->timer);
143		substream->timer = NULL;
144	}
145}