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 Lesser 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 Lesser 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
  29 #ifdef HAVE_SYS_POLL_H
  30 #include <sys/poll.h>
  31 #else
  32 #include "poll.h"
  33 #endif
  34
  35 #include <asoundlib.h>
  36
  37 #include "module.h"
  38 #include "core.h"
  39 #include "memchunk.h"
  40 #include "sink.h"
  41 #include "modargs.h"
  42 #include "util.h"
  43 #include "sample-util.h"
  44 #include "alsa-util.h"
  45 #include "xmalloc.h"
  46 #include "log.h"
  47 #include "module-alsa-source-symdef.h"
  48
  49 PA_MODULE_AUTHOR("Lennart Poettering")
  50 PA_MODULE_DESCRIPTION("ALSA Source")
  51 PA_MODULE_VERSION(PACKAGE_VERSION)
  52 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>")
  53
  54 struct userdata {
  55     snd_pcm_t *pcm_handle;
  56     pa_source *source;
  57     pa_io_event **io_events;
  58     unsigned n_io_events;
  59
  60     size_t frame_size, fragment_size;
  61     pa_memchunk memchunk;
  62     pa_module *module;
  63 };
  64
  65 static const char* const valid_modargs[] = {
  66     "device",
  67     "source_name",
  68     "channels",
  69     "rate",
  70     "format",
  71     "fragments",
  72     "fragment_size",
  73     NULL
  74 };
  75
  76 #define DEFAULT_SOURCE_NAME "alsa_input"
  77 #define DEFAULT_DEVICE "hw:0,0"
  78
  79 static void update_usage(struct userdata *u) {
  80    pa_module_set_used(u->module,
  81                       (u->source ? pa_idxset_size(u->source->outputs) : 0));
  82 }
  83
  84 static void xrun_recovery(struct userdata *u) {
  85     assert(u);
  86
  87     pa_log(__FILE__": *** ALSA-XRUN (capture) ***\n");
  88
  89     if (snd_pcm_prepare(u->pcm_handle) < 0)
  90         pa_log(__FILE__": snd_pcm_prepare() failed\n");
  91 }
  92
  93 static void do_read(struct userdata *u) {
  94     assert(u);
  95
  96     update_usage(u);
  97
  98     for (;;) {
  99         pa_memchunk post_memchunk;
 100         snd_pcm_sframes_t frames;
 101         size_t l;
 102
 103         if (!u->memchunk.memblock) {
 104             u->memchunk.memblock = pa_memblock_new(u->memchunk.length = u->fragment_size, u->source->core->memblock_stat);
 105             u->memchunk.index = 0;
 106         }
 107
 108         assert(u->memchunk.memblock && u->memchunk.memblock->data && u->memchunk.length && u->memchunk.memblock->length && (u->memchunk.length % u->frame_size) == 0);
 109
 110         if ((frames = snd_pcm_readi(u->pcm_handle, (uint8_t*) u->memchunk.memblock->data + u->memchunk.index, u->memchunk.length / u->frame_size)) < 0) {
 111             if (frames == -EAGAIN)
 112                 return;
 113
 114             if (frames == -EPIPE) {
 115                 xrun_recovery(u);
 116                 continue;
 117             }
 118
 119             pa_log(__FILE__": snd_pcm_readi() failed: %s\n", strerror(-frames));
 120             return;
 121         }
 122
 123         l = frames * u->frame_size;
 124
 125         post_memchunk = u->memchunk;
 126         post_memchunk.length = l;
 127
 128         pa_source_post(u->source, &post_memchunk);
 129
 130         u->memchunk.index += l;
 131         u->memchunk.length -= l;
 132
 133         if (u->memchunk.length == 0) {
 134             pa_memblock_unref(u->memchunk.memblock);
 135             u->memchunk.memblock = NULL;
 136             u->memchunk.index = u->memchunk.length = 0;
 137         }
 138
 139         break;
 140     }
 141 }
 142
 143 static void io_callback(pa_mainloop_api*a, pa_io_event *e, PA_GCC_UNUSED int fd, PA_GCC_UNUSED pa_io_event_flags_t f, void *userdata) {
 144     struct userdata *u = userdata;
 145     assert(u && a && e);
 146
 147     if (snd_pcm_state(u->pcm_handle) == SND_PCM_STATE_XRUN)
 148         xrun_recovery(u);
 149
 150     do_read(u);
 151 }
 152
 153 static pa_usec_t source_get_latency_cb(pa_source *s) {
 154     struct userdata *u = s->userdata;
 155     snd_pcm_sframes_t frames;
 156     assert(s && u && u->source);
 157
 158     if (snd_pcm_delay(u->pcm_handle, &frames) < 0) {
 159         pa_log(__FILE__": failed to get delay\n");
 160         s->get_latency = NULL;
 161         return 0;
 162     }
 163
 164     return pa_bytes_to_usec(frames * u->frame_size, &s->sample_spec);
 165 }
 166
 167 int pa__init(pa_core *c, pa_module*m) {
 168     pa_modargs *ma = NULL;
 169     int ret = -1;
 170     struct userdata *u = NULL;
 171     const char *dev;
 172     pa_sample_spec ss;
 173     unsigned periods, fragsize;
 174     snd_pcm_uframes_t period_size;
 175     size_t frame_size;
 176     int err;
 177
 178     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 179         pa_log(__FILE__": failed to parse module arguments\n");
 180         goto fail;
 181     }
 182
 183     ss = c->default_sample_spec;
 184     if (pa_modargs_get_sample_spec(ma, &ss) < 0) {
 185         pa_log(__FILE__": failed to parse sample specification\n");
 186         goto fail;
 187     }
 188     frame_size = pa_frame_size(&ss);
 189
 190     periods = 12;
 191     fragsize = 1024;
 192     if (pa_modargs_get_value_u32(ma, "fragments", &periods) < 0 || pa_modargs_get_value_u32(ma, "fragment_size", &fragsize) < 0) {
 193         pa_log(__FILE__": failed to parse buffer metrics\n");
 194         goto fail;
 195     }
 196     period_size = fragsize;
 197
 198     u = pa_xmalloc0(sizeof(struct userdata));
 199     m->userdata = u;
 200     u->module = m;
 201
 202     snd_config_update_free_global();
 203     if ((err = snd_pcm_open(&u->pcm_handle, dev = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK)) < 0) {
 204         pa_log(__FILE__": Error opening PCM device %s: %s\n", dev, snd_strerror(err));
 205         goto fail;
 206     }
 207
 208     if ((err = pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &period_size)) < 0) {
 209         pa_log(__FILE__": Failed to set hardware parameters: %s\n", snd_strerror(err));
 210         goto fail;
 211     }
 212
 213     u->source = pa_source_new(c, __FILE__, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME), 0, &ss, NULL);
 214     assert(u->source);
 215
 216     u->source->userdata = u;
 217     u->source->get_latency = source_get_latency_cb;
 218     pa_source_set_owner(u->source, m);
 219     u->source->description = pa_sprintf_malloc("Advanced Linux Sound Architecture PCM on '%s'", dev);
 220
 221     if (pa_create_io_events(u->pcm_handle, c->mainloop, &u->io_events, &u->n_io_events, io_callback, u) < 0) {
 222         pa_log(__FILE__": failed to obtain file descriptors\n");
 223         goto fail;
 224     }
 225
 226     u->frame_size = frame_size;
 227     u->fragment_size = period_size;
 228
 229     pa_log(__FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);
 230
 231     u->memchunk.memblock = NULL;
 232     u->memchunk.index = u->memchunk.length = 0;
 233
 234     snd_pcm_start(u->pcm_handle);
 235
 236     ret = 0;
 237
 238 finish:
 239      if (ma)
 240          pa_modargs_free(ma);
 241
 242     return ret;
 243
 244 fail:
 245
 246     if (u)
 247         pa__done(c, m);
 248
 249     goto finish;
 250 }
 251
 252 void pa__done(pa_core *c, pa_module*m) {
 253     struct userdata *u;
 254     assert(c && m);
 255
 256     if (!(u = m->userdata))
 257         return;
 258
 259     if (u->source) {
 260         pa_source_disconnect(u->source);
 261         pa_source_unref(u->source);
 262     }
 263
 264     if (u->io_events)
 265         pa_free_io_events(c->mainloop, u->io_events, u->n_io_events);
 266
 267     if (u->pcm_handle) {
 268         snd_pcm_drop(u->pcm_handle);
 269         snd_pcm_close(u->pcm_handle);
 270     }
 271
 272     if (u->memchunk.memblock)
 273         pa_memblock_unref(u->memchunk.memblock);
 274
 275     pa_xfree(u);
 276 }
 277