Rework period/buffer size setting

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4768 c046a42c-6fe2-441c-8c8c-71466251a162

audio/alsaaudio.c

@@ -58,37 +58,15 @@ static struct {
     int period_size_out_overridden;
     int verbose;
 } conf = {
-#define DEFAULT_BUFFER_SIZE 1024
-#define DEFAULT_PERIOD_SIZE 256
-#ifdef HIGH_LATENCY
-    .size_in_usec_in = 1,
-    .size_in_usec_out = 1,
-#endif
     .pcm_name_out = "default",
     .pcm_name_in = "default",
-#ifdef HIGH_LATENCY
-    .buffer_size_in = 400000,
-    .period_size_in = 400000 / 4,
-    .buffer_size_out = 400000,
-    .period_size_out = 400000 / 4,
-#else
-    .buffer_size_in = DEFAULT_BUFFER_SIZE * 4,
-    .period_size_in = DEFAULT_PERIOD_SIZE * 4,
-    .buffer_size_out = DEFAULT_BUFFER_SIZE,
-    .period_size_out = DEFAULT_PERIOD_SIZE,
-    .buffer_size_in_overridden = 0,
-    .buffer_size_out_overridden = 0,
-    .period_size_in_overridden = 0,
-    .period_size_out_overridden = 0,
-#endif
-    .threshold = 0,
-    .verbose = 0
 };
 
 struct alsa_params_req {
     int freq;
     snd_pcm_format_t fmt;
     int nchannels;
+    int size_in_usec;
     unsigned int buffer_size;
     unsigned int period_size;
 };
@@ -286,17 +264,16 @@ static int alsa_open (int in, struct alsa_params_req *req,
     snd_pcm_t *handle;
     snd_pcm_hw_params_t *hw_params;
     int err;
+    int size_in_usec;
     unsigned int freq, nchannels;
     const char *pcm_name = in ? conf.pcm_name_in : conf.pcm_name_out;
-    unsigned int period_size, buffer_size;
     snd_pcm_uframes_t obt_buffer_size;
     const char *typ = in ? "ADC" : "DAC";
     snd_pcm_format_t obtfmt;
 
     freq = req->freq;
-    period_size = req->period_size;
-    buffer_size = req->buffer_size;
     nchannels = req->nchannels;
+    size_in_usec = req->size_in_usec;
 
     snd_pcm_hw_params_alloca (&hw_params);
 
@@ -356,130 +333,61 @@ static int alsa_open (int in, struct alsa_params_req *req,
         goto err;
     }
 
-    if (!((in && conf.size_in_usec_in) || (!in && conf.size_in_usec_out))) {
-        if (!buffer_size) {
-            buffer_size = DEFAULT_BUFFER_SIZE;
-            period_size= DEFAULT_PERIOD_SIZE;
-        }
-    }
-
-    if (buffer_size) {
-        if ((in && conf.size_in_usec_in) || (!in && conf.size_in_usec_out)) {
-            if (period_size) {
-                err = snd_pcm_hw_params_set_period_time_near (
-                    handle,
-                    hw_params,
-                    &period_size,
-                    0
-                    );
-                if (err < 0) {
-                    alsa_logerr2 (err, typ,
-                                  "Failed to set period time %d\n",
-                                  req->period_size);
-                    goto err;
-                }
-            }
+    if (req->buffer_size) {
+        if (size_in_usec) {
+            int dir = 0;
+            unsigned int btime = req->buffer_size;
 
             err = snd_pcm_hw_params_set_buffer_time_near (
                 handle,
                 hw_params,
-                &buffer_size,
-                0
+                &btime,
+                &dir
                 );
-
-            if (err < 0) {
-                alsa_logerr2 (err, typ,
-                              "Failed to set buffer time %d\n",
-                              req->buffer_size);
-                goto err;
-            }
         }
         else {
-            int dir;
-            snd_pcm_uframes_t minval;
-
-            if (period_size) {
-                minval = period_size;
-                dir = 0;
-
-                err = snd_pcm_hw_params_get_period_size_min (
-                    hw_params,
-                    &minval,
-                    &dir
-                    );
-                if (err < 0) {
-                    alsa_logerr (
-                        err,
-                        "Could not get minmal period size for %s\n",
-                        typ
-                        );
-                }
-                else {
-                    if (period_size < minval) {
-                        if ((in && conf.period_size_in_overridden)
-                            || (!in && conf.period_size_out_overridden)) {
-                            dolog ("%s period size(%d) is less "
-                                   "than minmal period size(%ld)\n",
-                                   typ,
-                                   period_size,
-                                   minval);
-                        }
-                        period_size = minval;
-                    }
-                }
+            snd_pcm_uframes_t bsize = req->buffer_size;
 
-                err = snd_pcm_hw_params_set_period_size (
-                    handle,
-                    hw_params,
-                    period_size,
-                    0
-                    );
-                if (err < 0) {
-                    alsa_logerr2 (err, typ, "Failed to set period size %d\n",
-                                  req->period_size);
-                    goto err;
-                }
-            }
+            err = snd_pcm_hw_params_set_buffer_size_near (
+                handle,
+                hw_params,
+                &bsize
+                );
+        }
+        if (err < 0) {
+            alsa_logerr2 (err, typ, "Failed to set buffer %s to %d\n",
+                          size_in_usec ? "time" : "size", req->buffer_size);
+            goto err;
+        }
+    }
+
+    if (req->period_size) {
+        if (size_in_usec) {
+            int dir = 0;
+            unsigned int ptime = req->period_size;
 
-            minval = buffer_size;
-            err = snd_pcm_hw_params_get_buffer_size_min (
+            err = snd_pcm_hw_params_set_period_time_near (
+                handle,
                 hw_params,
-                &minval
+                &ptime,
+                &dir
                 );
-            if (err < 0) {
-                alsa_logerr (err, "Could not get minmal buffer size for %s\n",
-                             typ);
-            }
-            else {
-                if (buffer_size < minval) {
-                    if ((in && conf.buffer_size_in_overridden)
-                        || (!in && conf.buffer_size_out_overridden)) {
-                        dolog (
-                            "%s buffer size(%d) is less "
-                            "than minimal buffer size(%ld)\n",
-                            typ,
-                            buffer_size,
-                            minval
-                            );
-                    }
-                    buffer_size = minval;
-                }
-            }
+        }
+        else {
+            snd_pcm_uframes_t psize = req->period_size;
 
-            err = snd_pcm_hw_params_set_buffer_size (
+            err = snd_pcm_hw_params_set_buffer_size_near (
                 handle,
                 hw_params,
-                buffer_size
+                &psize
                 );
-            if (err < 0) {
-                alsa_logerr2 (err, typ, "Failed to set buffer size %d\n",
-                              req->buffer_size);
-                goto err;
-            }
         }
-    }
-    else {
-        dolog ("warning: Buffer size is not set\n");
+
+        if (err < 0) {
+            alsa_logerr2 (err, typ, "Failed to set period %s to %d\n",
+                          size_in_usec ? "time" : "size", req->period_size);
+            goto err;
+        }
     }
 
     err = snd_pcm_hw_params (handle, hw_params);
@@ -697,6 +605,7 @@ static int alsa_init_out (HWVoiceOut *hw, audsettings_t *as)
     req.nchannels = as->nchannels;
     req.period_size = conf.period_size_out;
     req.buffer_size = conf.buffer_size_out;
+    req.size_in_usec = conf.size_in_usec_in;
 
     if (alsa_open (0, &req, &obt, &handle)) {
         return -1;
@@ -774,6 +683,7 @@ static int alsa_init_in (HWVoiceIn *hw, audsettings_t *as)
     req.nchannels = as->nchannels;
     req.period_size = conf.period_size_in;
     req.buffer_size = conf.buffer_size_in;
+    req.size_in_usec = conf.size_in_usec_in;
 
     if (alsa_open (1, &req, &obt, &handle)) {
         return -1;
@@ -953,16 +863,20 @@ static struct audio_option alsa_options[] = {
     {"DAC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_out,
      "DAC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
     {"DAC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_out,
-     "DAC period size", &conf.period_size_out_overridden, 0},
+     "DAC period size (0 to go with system default)",
+     &conf.period_size_out_overridden, 0},
     {"DAC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_out,
-     "DAC buffer size", &conf.buffer_size_out_overridden, 0},
+     "DAC buffer size (0 to go with system default)",
+     &conf.buffer_size_out_overridden, 0},
 
     {"ADC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_in,
      "ADC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
     {"ADC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_in,
-     "ADC period size", &conf.period_size_in_overridden, 0},
+     "ADC period size (0 to go with system default)",
+     &conf.period_size_in_overridden, 0},
     {"ADC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_in,
-     "ADC buffer size", &conf.buffer_size_in_overridden, 0},
+     "ADC buffer size (0 to go with system default)",
+     &conf.buffer_size_in_overridden, 0},
 
     {"THRESHOLD", AUD_OPT_INT, &conf.threshold,
      "(undocumented)", NULL, 0},