option to use ALSA default fragment number and size

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@295 fefdeb5f-60dc-0310-8127-8f9354f1896f

doc/todo

@@ -1,17 +1,16 @@
 *** $Id$ ***
 
 *** 0.7 ****
-- per-channel volume
-- option to use default fragment size on alsa drivers
-- improve module-oss-mmap latency measurement
-- add radio module
 - make most buffer sizes dependant on the sample type
 - limit all resources
 - commenting
-- module-tunnel: use latency interpolation
 - polish for starting polypaudio as root/system-wide instance
 
 ** later ***
+- per-channel volume
+- improve module-oss-mmap latency measurement
+- module-tunnel: improve latency calculation
+- add radio module
 - pass meta info for hearing impaired
 - add sync API
 - X11: support for the X11 synchronization extension

polyp/alsa-util.c

@@ -30,8 +30,9 @@
 #include "sample.h"
 #include "xmalloc.h"
 
-int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, struct pa_sample_spec *ss, uint32_t *periods, snd_pcm_uframes_t *buffer_size) {
+int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, struct pa_sample_spec *ss, uint32_t *periods, snd_pcm_uframes_t *period_size) {
-    int ret = 0;
+    int ret = -1;
+    snd_pcm_uframes_t buffer_size;
     snd_pcm_hw_params_t *hwparams = NULL;
     static const snd_pcm_format_t format_trans[] = {
         [PA_SAMPLE_U8] = SND_PCM_FORMAT_U8,
@@ -42,21 +43,39 @@ int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, struct pa_sample_spec *ss, uint
         [PA_SAMPLE_FLOAT32LE] = SND_PCM_FORMAT_FLOAT_LE,
         [PA_SAMPLE_FLOAT32BE] = SND_PCM_FORMAT_FLOAT_BE,
     };
-
+    assert(pcm_handle && ss && periods && period_size);
+    
     if (snd_pcm_hw_params_malloc(&hwparams) < 0 ||
         snd_pcm_hw_params_any(pcm_handle, hwparams) < 0 ||
         snd_pcm_hw_params_set_access(pcm_handle, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED) < 0 ||
         snd_pcm_hw_params_set_format(pcm_handle, hwparams, format_trans[ss->format]) < 0 ||
         snd_pcm_hw_params_set_rate_near(pcm_handle, hwparams, &ss->rate, NULL) < 0 ||
         snd_pcm_hw_params_set_channels(pcm_handle, hwparams, ss->channels) < 0 ||
-        snd_pcm_hw_params_set_periods_near(pcm_handle, hwparams, periods, NULL) < 0 || 
+        (*periods > 0 && snd_pcm_hw_params_set_periods_near(pcm_handle, hwparams, periods, NULL) < 0) || 
-        snd_pcm_hw_params_set_buffer_size_near(pcm_handle, hwparams, buffer_size) < 0 || 
+        (*period_size > 0 && snd_pcm_hw_params_set_period_size_near(pcm_handle, hwparams, period_size, NULL) < 0) || 
-        snd_pcm_hw_params(pcm_handle, hwparams) < 0) {
+        snd_pcm_hw_params(pcm_handle, hwparams) < 0)
-        ret = -1;
+        goto finish;
-    }
+    
+    if (snd_pcm_prepare(pcm_handle) < 0)
+        goto finish;
 
+    if (snd_pcm_hw_params_current(pcm_handle, hwparams) < 0)
+        goto finish;
+    
+    if (snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size) < 0 ||
+        snd_pcm_hw_params_get_period_size(hwparams, period_size, NULL) < 0)
+        goto finish;
+
+    assert(buffer_size > 0 && *period_size > 0);
+    *periods = buffer_size / *period_size;
+    assert(*periods > 0);
+    
+    ret = 0;
+    
+finish:
     if (hwparams)
         snd_pcm_hw_params_free(hwparams);
+    
     return ret;
 }
 

polyp/alsa-util.h

@@ -27,7 +27,7 @@
 #include "sample.h"
 #include "mainloop-api.h"
 
-int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, struct pa_sample_spec *ss, uint32_t *periods, snd_pcm_uframes_t *buffer_size);
+int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, struct pa_sample_spec *ss, uint32_t *periods, snd_pcm_uframes_t *period_size);
 
 int pa_create_io_events(snd_pcm_t *pcm_handle, struct pa_mainloop_api *m, struct pa_io_event ***io_events, unsigned *n_io_events, void (*cb)(struct pa_mainloop_api*a, struct pa_io_event *e, int fd, enum pa_io_event_flags events, void *userdata), void *userdata);
 void pa_free_io_events(struct pa_mainloop_api* m, struct pa_io_event **io_sources, unsigned n_io_sources);

polyp/module-alsa-sink.c

@@ -174,8 +174,8 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
     struct userdata *u = NULL;
     const char *dev;
     struct pa_sample_spec ss;
-    unsigned periods, fragsize;
+    uint32_t periods, fragsize;
-    snd_pcm_uframes_t buffer_size;
+    snd_pcm_uframes_t period_size;
     size_t frame_size;
 
     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
@@ -196,7 +196,7 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
         pa_log(__FILE__": failed to parse buffer metrics\n");
         goto fail;
     }
-    buffer_size = fragsize/frame_size*periods;
+    period_size = fragsize;
     
     u = pa_xmalloc0(sizeof(struct userdata));
     m->userdata = u;
@@ -207,7 +207,7 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
         goto fail;
     }
 
-    if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &buffer_size) < 0) {
+    if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &period_size) < 0) {
         pa_log(__FILE__": Failed to set hardware parameters\n");
         goto fail;
     }
@@ -226,7 +226,7 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
     }
     
     u->frame_size = frame_size;
-    u->fragment_size = buffer_size*u->frame_size/periods;
+    u->fragment_size = period_size;
 
     pa_log(__FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);
 

polyp/module-alsa-source.c

@@ -166,7 +166,7 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
     const char *dev;
     struct pa_sample_spec ss;
     unsigned periods, fragsize;
-    snd_pcm_uframes_t buffer_size;
+    snd_pcm_uframes_t period_size;
     size_t frame_size;
     
     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
@@ -187,7 +187,7 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
         pa_log(__FILE__": failed to parse buffer metrics\n");
         goto fail;
     }
-    buffer_size = fragsize/frame_size*periods;
+    period_size = fragsize;
     
     u = pa_xmalloc0(sizeof(struct userdata));
     m->userdata = u;
@@ -198,7 +198,7 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
         goto fail;
     }
 
-    if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &buffer_size) < 0) {
+    if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &period_size) < 0) {
         pa_log(__FILE__": Failed to set hardware parameters\n");
         goto fail;
     }
@@ -217,7 +217,7 @@ int pa__init(struct pa_core *c, struct pa_module*m) {
     }
 
     u->frame_size = frame_size;
-    u->fragment_size = buffer_size*u->frame_size/periods;
+    u->fragment_size = period_size;
 
     pa_log(__FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);