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