// SPDX-License-Identifier: GPL-2.0-or-later/* * Digital Audio (PCM) abstract layer * Copyright (c) by Jaroslav Kysela <perex@perex.cz> */ #include <linux/time.h>#include <linux/gcd.h>#include <sound/core.h>#include <sound/pcm.h>#include <sound/timer.h> #include "pcm_local.h" /* * Timer functions */ void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream){ unsigned long rate, mult, fsize, l, post; struct snd_pcm_runtime *runtime = substream->runtime; mult = 1000000000; rate = runtime->rate; if (snd_BUG_ON(!rate)) return; l = gcd(mult, rate); mult /= l; rate /= l; fsize = runtime->period_size; if (snd_BUG_ON(!fsize)) return; l = gcd(rate, fsize); rate /= l; fsize /= l; post = 1; while ((mult * fsize) / fsize != mult) { mult /= 2; post *= 2; } if (rate == 0) { pcm_err(substream->pcm, "pcm timer resolution out of range (rate = %u, period_size = %lu)\n", runtime->rate, runtime->period_size); runtime->timer_resolution = -1; return; } runtime->timer_resolution = (mult * fsize / rate) * post;} static unsigned long snd_pcm_timer_resolution(struct snd_timer * timer){ struct snd_pcm_substream *substream; substream = timer->private_data; return substream->runtime ? substream->runtime->timer_resolution : 0;} static int snd_pcm_timer_start(struct snd_timer * timer){ struct snd_pcm_substream *substream; substream = snd_timer_chip(timer); substream->timer_running = 1; return 0;} static int snd_pcm_timer_stop(struct snd_timer * timer){ struct snd_pcm_substream *substream; substream = snd_timer_chip(timer); substream->timer_running = 0; return 0;} static const struct snd_timer_hardware snd_pcm_timer ={ .flags = SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_SLAVE, .resolution = 0, .ticks = 1, .c_resolution = snd_pcm_timer_resolution, .start = snd_pcm_timer_start, .stop = snd_pcm_timer_stop,}; /* * Init functions */ static void snd_pcm_timer_free(struct snd_timer *timer){ struct snd_pcm_substream *substream = timer->private_data; substream->timer = NULL;} void snd_pcm_timer_init(struct snd_pcm_substream *substream){ struct snd_timer_id tid; struct snd_timer *timer; tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE; tid.dev_class = SNDRV_TIMER_CLASS_PCM; tid.card = substream->pcm->card->number; tid.device = substream->pcm->device; tid.subdevice = (substream->number << 1) | (substream->stream & 1); if (snd_timer_new(substream->pcm->card, "PCM", &tid, &timer) < 0) return; sprintf(timer->name, "PCM %s %i-%i-%i", snd_pcm_direction_name(substream->stream), tid.card, tid.device, tid.subdevice); timer->hw = snd_pcm_timer; if (snd_device_register(timer->card, timer) < 0) { snd_device_free(timer->card, timer); return; } timer->private_data = substream; timer->private_free = snd_pcm_timer_free; substream->timer = timer;} void snd_pcm_timer_done(struct snd_pcm_substream *substream){ if (substream->timer) { snd_device_free(substream->pcm->card, substream->timer); substream->timer = NULL; }}
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Digital Audio (PCM) abstract layer
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
*/
#include <linux/time.h>
#include <linux/gcd.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/timer.h>
#include "pcm_local.h"
/*
* Timer functions
*/
void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream)
{
unsigned long rate, mult, fsize, l, post;
struct snd_pcm_runtime *runtime = substream->runtime;
mult = 1000000000;
rate = runtime->rate;
if (snd_BUG_ON(!rate))
return;
l = gcd(mult, rate);
mult /= l;
rate /= l;
fsize = runtime->period_size;
if (snd_BUG_ON(!fsize))
return;
l = gcd(rate, fsize);
rate /= l;
fsize /= l;
post = 1;
while ((mult * fsize) / fsize != mult) {
mult /= 2;
post *= 2;
}
if (rate == 0) {
pcm_err(substream->pcm,
"pcm timer resolution out of range (rate = %u, period_size = %lu)\n",
runtime->rate, runtime->period_size);
runtime->timer_resolution = -1;
return;
}
runtime->timer_resolution = (mult * fsize / rate) * post;
}
static unsigned long snd_pcm_timer_resolution(struct snd_timer * timer)
{
struct snd_pcm_substream *substream;
substream = timer->private_data;
return substream->runtime ? substream->runtime->timer_resolution : 0;
}
static int snd_pcm_timer_start(struct snd_timer * timer)
{
struct snd_pcm_substream *substream;
substream = snd_timer_chip(timer);
substream->timer_running = 1;
return 0;
}
static int snd_pcm_timer_stop(struct snd_timer * timer)
{
struct snd_pcm_substream *substream;
substream = snd_timer_chip(timer);
substream->timer_running = 0;
return 0;
}
static const struct snd_timer_hardware snd_pcm_timer =
{
.flags = SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_SLAVE,
.resolution = 0,
.ticks = 1,
.c_resolution = snd_pcm_timer_resolution,
.start = snd_pcm_timer_start,
.stop = snd_pcm_timer_stop,
};
/*
* Init functions
*/
static void snd_pcm_timer_free(struct snd_timer *timer)
{
struct snd_pcm_substream *substream = timer->private_data;
substream->timer = NULL;
}
void snd_pcm_timer_init(struct snd_pcm_substream *substream)
{
struct snd_timer_id tid;
struct snd_timer *timer;
tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
tid.dev_class = SNDRV_TIMER_CLASS_PCM;
tid.card = substream->pcm->card->number;
tid.device = substream->pcm->device;
tid.subdevice = (substream->number << 1) | (substream->stream & 1);
if (snd_timer_new(substream->pcm->card, "PCM", &tid, &timer) < 0)
return;
sprintf(timer->name, "PCM %s %i-%i-%i",
snd_pcm_direction_name(substream->stream),
tid.card, tid.device, tid.subdevice);
timer->hw = snd_pcm_timer;
if (snd_device_register(timer->card, timer) < 0) {
snd_device_free(timer->card, timer);
return;
}
timer->private_data = substream;
timer->private_free = snd_pcm_timer_free;
substream->timer = timer;
}
void snd_pcm_timer_done(struct snd_pcm_substream *substream)
{
if (substream->timer) {
snd_device_free(substream->pcm->card, substream->timer);
substream->timer = NULL;
}
}