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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}
v3.15
 
  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/*
 29 *  Timer functions
 30 */
 31
 32void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream)
 33{
 34	unsigned long rate, mult, fsize, l, post;
 35	struct snd_pcm_runtime *runtime = substream->runtime;
 36	
 37        mult = 1000000000;
 38	rate = runtime->rate;
 39	if (snd_BUG_ON(!rate))
 40		return;
 41	l = gcd(mult, rate);
 42	mult /= l;
 43	rate /= l;
 44	fsize = runtime->period_size;
 45	if (snd_BUG_ON(!fsize))
 46		return;
 47	l = gcd(rate, fsize);
 48	rate /= l;
 49	fsize /= l;
 50	post = 1;
 51	while ((mult * fsize) / fsize != mult) {
 52		mult /= 2;
 53		post *= 2;
 54	}
 55	if (rate == 0) {
 56		pcm_err(substream->pcm,
 57			"pcm timer resolution out of range (rate = %u, period_size = %lu)\n",
 58			runtime->rate, runtime->period_size);
 59		runtime->timer_resolution = -1;
 60		return;
 61	}
 62	runtime->timer_resolution = (mult * fsize / rate) * post;
 63}
 64
 65static unsigned long snd_pcm_timer_resolution(struct snd_timer * timer)
 66{
 67	struct snd_pcm_substream *substream;
 68	
 69	substream = timer->private_data;
 70	return substream->runtime ? substream->runtime->timer_resolution : 0;
 71}
 72
 73static int snd_pcm_timer_start(struct snd_timer * timer)
 74{
 75	struct snd_pcm_substream *substream;
 76	
 77	substream = snd_timer_chip(timer);
 78	substream->timer_running = 1;
 79	return 0;
 80}
 81
 82static int snd_pcm_timer_stop(struct snd_timer * timer)
 83{
 84	struct snd_pcm_substream *substream;
 85	
 86	substream = snd_timer_chip(timer);
 87	substream->timer_running = 0;
 88	return 0;
 89}
 90
 91static struct snd_timer_hardware snd_pcm_timer =
 92{
 93	.flags =	SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_SLAVE,
 94	.resolution =	0,
 95	.ticks =	1,
 96	.c_resolution =	snd_pcm_timer_resolution,
 97	.start =	snd_pcm_timer_start,
 98	.stop =		snd_pcm_timer_stop,
 99};
100
101/*
102 *  Init functions
103 */
104
105static void snd_pcm_timer_free(struct snd_timer *timer)
106{
107	struct snd_pcm_substream *substream = timer->private_data;
108	substream->timer = NULL;
109}
110
111void snd_pcm_timer_init(struct snd_pcm_substream *substream)
112{
113	struct snd_timer_id tid;
114	struct snd_timer *timer;
115	
116	tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
117	tid.dev_class = SNDRV_TIMER_CLASS_PCM;
118	tid.card = substream->pcm->card->number;
119	tid.device = substream->pcm->device;
120	tid.subdevice = (substream->number << 1) | (substream->stream & 1);
121	if (snd_timer_new(substream->pcm->card, "PCM", &tid, &timer) < 0)
122		return;
123	sprintf(timer->name, "PCM %s %i-%i-%i",
124			substream->stream == SNDRV_PCM_STREAM_CAPTURE ?
125				"capture" : "playback",
126			tid.card, tid.device, tid.subdevice);
127	timer->hw = snd_pcm_timer;
128	if (snd_device_register(timer->card, timer) < 0) {
129		snd_device_free(timer->card, timer);
130		return;
131	}
132	timer->private_data = substream;
133	timer->private_free = snd_pcm_timer_free;
134	substream->timer = timer;
135}
136
137void snd_pcm_timer_done(struct snd_pcm_substream *substream)
138{
139	if (substream->timer) {
140		snd_device_free(substream->pcm->card, substream->timer);
141		substream->timer = NULL;
142	}
143}