From 7c74542c587425c1c3f0abb17fe3125c338bb47d Mon Sep 17 00:00:00 2001
From: twinaphex <autechre1024@hotmail.com>
Date: Sat, 6 Jul 2013 22:45:10 +0200
Subject: [PATCH] (ALSA QSA) Merge latest patches by CatalystG

---
 blackberry-qnx/alsa_qsa.c | 38 ++++++++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 14 deletions(-)

diff --git a/blackberry-qnx/alsa_qsa.c b/blackberry-qnx/alsa_qsa.c
index 0d48015c01..cc44d7c102 100644
--- a/blackberry-qnx/alsa_qsa.c
+++ b/blackberry-qnx/alsa_qsa.c
@@ -69,15 +69,16 @@ static void *alsa_qsa_init(const char *device, unsigned rate, unsigned latency)
 
    params.format.interleave = 1;
    params.format.format = SND_PCM_SFMT_S16_LE;
-   params.format.rate = rate; 
+   params.format.rate = rate;
    params.format.voices = 2;
 
-   params.start_mode = SND_PCM_START_DATA;
-   params.stop_mode = SND_PCM_STOP_ROLLOVER;
+   params.start_mode = SND_PCM_START_FULL;
+   params.stop_mode = SND_PCM_STOP_STOP;
 
-   params.buf.block.frag_size = 4096;
+   params.buf.block.frags_max = (latency * rate * 4) / (1000 * (1 << 10)) - 1;
+   params.buf.block.frag_size = 1024;
    params.buf.block.frags_min = 1;
-   params.buf.block.frags_max = 19;
+
 
    if ((err = snd_pcm_plugin_params(alsa->pcm, &params)) < 0)
    {
@@ -93,7 +94,7 @@ static void *alsa_qsa_init(const char *device, unsigned rate, unsigned latency)
       goto error;
    }
 
-   alsa->buffer_size = setup.buf.block.frag_size * 19; /* is this in bytes? */
+   alsa->buffer_size = setup.buf.block.frag_size * (setup.buf.block.frags_max+1); /* is this in bytes? */
    RARCH_LOG("[ALSA QSA]: buffer size: %d bytes (?)\n", alsa->buffer_size);
 
    if ((err = snd_pcm_plugin_prepare(alsa->pcm, SND_PCM_CHANNEL_PLAYBACK)) < 0)
@@ -114,21 +115,28 @@ error:
    return (void*)-1;
 }
 
-
 static ssize_t alsa_qsa_write(void *data, const void *buf, size_t size)
 {
-   int err;
+   int written, err;
    alsa_t *alsa = (alsa_t*)data;
    snd_pcm_channel_status_t status = {0};
 
-   if ((err = snd_pcm_plugin_status(alsa->pcm, &status)) < 0)
-      RARCH_ERR("[ALSA QSA]: Error reading status: %s\n", snd_strerror(err));
+   written = snd_pcm_plugin_write(alsa->pcm, buf, size);
 
-   if ((err = snd_pcm_plugin_write(alsa->pcm, buf, size)) < 0)
-      RARCH_ERR("[ALSA QSA]: Error writing PCM: %s\n", snd_strerror(err));
+   if (written < size)
+   {
+      status.channel = SND_PCM_CHANNEL_PLAYBACK;
 
-   return size;
-}
+      if ((err = snd_pcm_plugin_status(alsa->pcm, &status)) < 0)
+         RARCH_ERR("[ALSA QSA]: Error reading status: %s\n", snd_strerror(err));
+
+      if (status.status == SND_PCM_STATUS_UNDERRUN)
+         if (snd_pcm_plugin_prepare(alsa->pcm, SND_PCM_CHANNEL_PLAYBACK) < 0)
+            RARCH_ERR("[ALSA QSA]: Underrun - playback channel prepare error.\n");
+   }
+
+    return size;
+ }
 
 static bool alsa_qsa_stop(void *data)
 {
@@ -221,6 +229,7 @@ static size_t alsa_qsa_write_avail(void *data)
    alsa_t *alsa = (alsa_t*)data;
    snd_pcm_channel_status_t status = {0};
 
+   status.channel = SND_PCM_CHANNEL_PLAYBACK;
    snd_pcm_plugin_status(alsa->pcm, &status);
 
    return status.free;
@@ -244,3 +253,4 @@ const audio_driver_t audio_alsa = {
    alsa_qsa_write_avail,
    alsa_qsa_buffer_size,
 };
+