code.delx.au - pulseaudio/blob - polyp/module-alsa-source.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of polypaudio.
   5
   6   polypaudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   polypaudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with polypaudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <assert.h>
  27 #include <stdio.h>
  28 #include <sys/poll.h>
  29
  30 #include <asoundlib.h>
  31
  32 #include "module.h"
  33 #include "core.h"
  34 #include "memchunk.h"
  35 #include "sink.h"
  36 #include "modargs.h"
  37 #include "util.h"
  38 #include "sample-util.h"
  39 #include "alsa-util.h"
  40 #include "xmalloc.h"
  41 #include "log.h"
  42
  43 PA_MODULE_AUTHOR("Lennart Poettering")
  44 PA_MODULE_DESCRIPTION("ALSA Source")
  45 PA_MODULE_VERSION(PACKAGE_VERSION)
  46 PA_MODULE_USAGE("source_name=<name for the source> device=<ALSA device> format=<sample format> channels=<number of channels> rate=<sample rate> fragments=<number of fragments> fragment_size=<fragment size>")
  47
  48 struct userdata {
  49     snd_pcm_t *pcm_handle;
  50     struct pa_source *source;
  51     struct pa_io_event **io_events;
  52     unsigned n_io_events;
  53
  54     size_t frame_size, fragment_size;
  55     struct pa_memchunk memchunk;
  56     struct pa_module *module;
  57 };
  58
  59 static const char* const valid_modargs[] = {
  60     "device",
  61     "source_name",
  62     "channels",
  63     "rate",
  64     "format",
  65     "fragments",
  66     "fragment_size",
  67     NULL
  68 };
  69
  70 #define DEFAULT_SOURCE_NAME "alsa_input"
  71 #define DEFAULT_DEVICE "hw:0,0"
  72
  73 static void update_usage(struct userdata *u) {
  74    pa_module_set_used(u->module,
  75                       (u->source ? pa_idxset_ncontents(u->source->outputs) : 0));
  76 }
  77
  78 static void xrun_recovery(struct userdata *u) {
  79     assert(u);
  80
  81     pa_log(__FILE__": *** ALSA-XRUN (capture) ***\n");
  82
  83     if (snd_pcm_prepare(u->pcm_handle) < 0)
  84         pa_log(__FILE__": snd_pcm_prepare() failed\n");
  85 }
  86
  87 static void do_read(struct userdata *u) {
  88     assert(u);
  89
  90     update_usage(u);
  91
  92     for (;;) {
  93         struct pa_memchunk post_memchunk;
  94         snd_pcm_sframes_t frames;
  95         size_t l;
  96
  97         if (!u->memchunk.memblock) {
  98             u->memchunk.memblock = pa_memblock_new(u->memchunk.length = u->fragment_size, u->source->core->memblock_stat);
  99             u->memchunk.index = 0;
 100         }
 101
 102         assert(u->memchunk.memblock && u->memchunk.memblock->data && u->memchunk.length && u->memchunk.memblock->length && (u->memchunk.length % u->frame_size) == 0);
 103
 104         if ((frames = snd_pcm_readi(u->pcm_handle, (uint8_t*) u->memchunk.memblock->data + u->memchunk.index, u->memchunk.length / u->frame_size)) < 0) {
 105             if (frames == -EAGAIN)
 106                 return;
 107
 108             if (frames == -EPIPE) {
 109                 xrun_recovery(u);
 110                 continue;
 111             }
 112
 113             pa_log(__FILE__": snd_pcm_readi() failed: %s\n", strerror(-frames));
 114             return;
 115         }
 116
 117         l = frames * u->frame_size;
 118
 119         post_memchunk = u->memchunk;
 120         post_memchunk.length = l;
 121
 122         pa_source_post(u->source, &post_memchunk);
 123
 124         u->memchunk.index += l;
 125         u->memchunk.length -= l;
 126
 127         if (u->memchunk.length == 0) {
 128             pa_memblock_unref(u->memchunk.memblock);
 129             u->memchunk.memblock = NULL;
 130             u->memchunk.index = u->memchunk.length = 0;
 131         }
 132
 133         break;
 134     }
 135 }
 136
 137 static void io_callback(struct pa_mainloop_api*a, struct pa_io_event *e, int fd, enum pa_io_event_flags f, void *userdata) {
 138     struct userdata *u = userdata;
 139     assert(u && a && e);
 140
 141     if (snd_pcm_state(u->pcm_handle) == SND_PCM_STATE_XRUN)
 142         xrun_recovery(u);
 143
 144     do_read(u);
 145 }
 146
 147 static pa_usec_t source_get_latency_cb(struct pa_source *s) {
 148     struct userdata *u = s->userdata;
 149     snd_pcm_sframes_t frames;
 150     assert(s && u && u->source);
 151
 152     if (snd_pcm_delay(u->pcm_handle, &frames) < 0) {
 153         pa_log(__FILE__": failed to get delay\n");
 154         s->get_latency = NULL;
 155         return 0;
 156     }
 157
 158     return pa_bytes_to_usec(frames * u->frame_size, &s->sample_spec);
 159 }
 160
 161 int pa__init(struct pa_core *c, struct pa_module*m) {
 162     struct pa_modargs *ma = NULL;
 163     int ret = -1;
 164     struct userdata *u = NULL;
 165     const char *dev;
 166     struct pa_sample_spec ss;
 167     unsigned periods, fragsize;
 168     snd_pcm_uframes_t buffer_size;
 169     size_t frame_size;
 170
 171     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 172         pa_log(__FILE__": failed to parse module arguments\n");
 173         goto fail;
 174     }
 175
 176     ss = c->default_sample_spec;
 177     if (pa_modargs_get_sample_spec(ma, &ss) < 0) {
 178         pa_log(__FILE__": failed to parse sample specification\n");
 179         goto fail;
 180     }
 181     frame_size = pa_frame_size(&ss);
 182
 183     periods = 12;
 184     fragsize = 1024;
 185     if (pa_modargs_get_value_u32(ma, "fragments", &periods) < 0 || pa_modargs_get_value_u32(ma, "fragment_size", &fragsize) < 0) {
 186         pa_log(__FILE__": failed to parse buffer metrics\n");
 187         goto fail;
 188     }
 189     buffer_size = fragsize/frame_size*periods;
 190
 191     u = pa_xmalloc0(sizeof(struct userdata));
 192     m->userdata = u;
 193     u->module = m;
 194
 195     if (snd_pcm_open(&u->pcm_handle, dev = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK) < 0) {
 196         pa_log(__FILE__": Error opening PCM device %s\n", dev);
 197         goto fail;
 198     }
 199
 200     if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &buffer_size) < 0) {
 201         pa_log(__FILE__": Failed to set hardware parameters\n");
 202         goto fail;
 203     }
 204
 205     u->source = pa_source_new(c, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME), 0, &ss);
 206     assert(u->source);
 207
 208     u->source->userdata = u;
 209     u->source->get_latency = source_get_latency_cb;
 210     pa_source_set_owner(u->source, m);
 211     u->source->description = pa_sprintf_malloc("Advanced Linux Sound Architecture PCM on '%s'", dev);
 212
 213     if (pa_create_io_events(u->pcm_handle, c->mainloop, &u->io_events, &u->n_io_events, io_callback, u) < 0) {
 214         pa_log(__FILE__": failed to obtain file descriptors\n");
 215         goto fail;
 216     }
 217
 218     u->frame_size = frame_size;
 219     u->fragment_size = buffer_size*u->frame_size/periods;
 220
 221     pa_log(__FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);
 222
 223     u->memchunk.memblock = NULL;
 224     u->memchunk.index = u->memchunk.length = 0;
 225
 226     snd_pcm_start(u->pcm_handle);
 227
 228     ret = 0;
 229
 230 finish:
 231      if (ma)
 232          pa_modargs_free(ma);
 233
 234     return ret;
 235
 236 fail:
 237
 238     if (u)
 239         pa__done(c, m);
 240
 241     goto finish;
 242 }
 243
 244 void pa__done(struct pa_core *c, struct pa_module*m) {
 245     struct userdata *u;
 246     assert(c && m);
 247
 248     if (!(u = m->userdata))
 249         return;
 250
 251     if (u->source) {
 252         pa_source_disconnect(u->source);
 253         pa_source_unref(u->source);
 254     }
 255
 256     if (u->io_events)
 257         pa_free_io_events(c->mainloop, u->io_events, u->n_io_events);
 258
 259     if (u->pcm_handle) {
 260         snd_pcm_drop(u->pcm_handle);
 261         snd_pcm_close(u->pcm_handle);
 262     }
 263
 264     if (u->memchunk.memblock)
 265         pa_memblock_unref(u->memchunk.memblock);
 266
 267     pa_xfree(u);
 268 }
 269