~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/sound/core/pcm_timer.c

Version: ~ [ linux-5.15-rc5 ] ~ [ linux-5.14.11 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.72 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.152 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.210 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.250 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.286 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.288 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 
 32 void 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 
 65 static 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 
 73 static 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 
 82 static 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 
 91 static 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 
105 static 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 
111 void 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 
137 void 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 }
144 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp