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Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
131 lines
3.0 KiB
C
131 lines
3.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Digital Audio (PCM) abstract layer
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* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
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*/
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#include <linux/time.h>
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#include <linux/gcd.h>
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#include <sound/core.h>
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#include <sound/pcm.h>
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#include <sound/timer.h>
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#include "pcm_local.h"
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/*
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* Timer functions
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*/
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void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream)
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{
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unsigned long rate, mult, fsize, l, post;
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struct snd_pcm_runtime *runtime = substream->runtime;
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mult = 1000000000;
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rate = runtime->rate;
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if (snd_BUG_ON(!rate))
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return;
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l = gcd(mult, rate);
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mult /= l;
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rate /= l;
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fsize = runtime->period_size;
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if (snd_BUG_ON(!fsize))
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return;
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l = gcd(rate, fsize);
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rate /= l;
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fsize /= l;
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post = 1;
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while ((mult * fsize) / fsize != mult) {
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mult /= 2;
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post *= 2;
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}
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if (rate == 0) {
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pcm_err(substream->pcm,
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"pcm timer resolution out of range (rate = %u, period_size = %lu)\n",
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runtime->rate, runtime->period_size);
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runtime->timer_resolution = -1;
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return;
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}
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runtime->timer_resolution = (mult * fsize / rate) * post;
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}
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static unsigned long snd_pcm_timer_resolution(struct snd_timer * timer)
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{
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struct snd_pcm_substream *substream;
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substream = timer->private_data;
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return substream->runtime ? substream->runtime->timer_resolution : 0;
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}
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static int snd_pcm_timer_start(struct snd_timer * timer)
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{
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struct snd_pcm_substream *substream;
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substream = snd_timer_chip(timer);
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substream->timer_running = 1;
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return 0;
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}
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static int snd_pcm_timer_stop(struct snd_timer * timer)
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{
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struct snd_pcm_substream *substream;
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substream = snd_timer_chip(timer);
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substream->timer_running = 0;
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return 0;
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}
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static struct snd_timer_hardware snd_pcm_timer =
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{
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.flags = SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_SLAVE,
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.resolution = 0,
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.ticks = 1,
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.c_resolution = snd_pcm_timer_resolution,
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.start = snd_pcm_timer_start,
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.stop = snd_pcm_timer_stop,
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};
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/*
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* Init functions
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*/
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static void snd_pcm_timer_free(struct snd_timer *timer)
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{
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struct snd_pcm_substream *substream = timer->private_data;
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substream->timer = NULL;
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}
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void snd_pcm_timer_init(struct snd_pcm_substream *substream)
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{
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struct snd_timer_id tid;
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struct snd_timer *timer;
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tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
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tid.dev_class = SNDRV_TIMER_CLASS_PCM;
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tid.card = substream->pcm->card->number;
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tid.device = substream->pcm->device;
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tid.subdevice = (substream->number << 1) | (substream->stream & 1);
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if (snd_timer_new(substream->pcm->card, "PCM", &tid, &timer) < 0)
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return;
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sprintf(timer->name, "PCM %s %i-%i-%i",
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substream->stream == SNDRV_PCM_STREAM_CAPTURE ?
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"capture" : "playback",
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tid.card, tid.device, tid.subdevice);
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timer->hw = snd_pcm_timer;
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if (snd_device_register(timer->card, timer) < 0) {
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snd_device_free(timer->card, timer);
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return;
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}
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timer->private_data = substream;
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timer->private_free = snd_pcm_timer_free;
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substream->timer = timer;
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}
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void snd_pcm_timer_done(struct snd_pcm_substream *substream)
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{
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if (substream->timer) {
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snd_device_free(substream->pcm->card, substream->timer);
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substream->timer = NULL;
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}
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}
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