调整alsa参数减小音频延时

external/eyesee-mpp/middleware/sun8iw21/media/audio/alsa_interface.c

@@ -22,8 +22,8 @@
 static char aioDebugfsPath[256] = {0};
 static unsigned int updateCnt = 0;
 
-#define PERIOD_SIZE (1024)
-#define PERIOD_COUNT (8)
+#define PERIOD_SIZE (256)
+#define PERIOD_COUNT (4)
 #define UPDATE_AIO_DEBUGFS_INFO(update_flag, item_flag, item, type, buf, path)  \
     do {                                                                        \
         if (update_flag & item_flag) {                                          \
@@ -388,6 +388,7 @@ int alsaSetPcmParams(PCM_CONFIG_S *pcmCfg)
 
     snd_pcm_uframes_t periodSize = PERIOD_SIZE;
     snd_pcm_uframes_t prePeriodSize = periodSize;
+    // alogd("size:%d count:%d\n", PERIOD_SIZE, PERIOD_COUNT);
     err = snd_pcm_hw_params_set_period_size_near(pcmCfg->handle, params, &periodSize, &dir);
     if (err < 0) {
         aloge("set_period_size_near error!");

target/allwinner/v851s-fastboot_sl100_back/busybox-init-base-files/etc/asound.conf

@@ -118,7 +118,7 @@ pcm.PlaybackRateDmix {
     }
     @args.PERIODSIZE {
         type integer
-        default 960 #1024
+        default 256 #1024
     }
     type plug
     slave.pcm {
@@ -135,7 +135,7 @@ pcm.PlaybackRateDmix {
                     rate        $SAMPLERATE
                     channels    $CHNNUM
                     period_size $PERIODSIZE
-                    periods 8
+                    periods 4
                 }
             }
             hooks.0 {

target/allwinner/v851s3-fastboot_sl100_front/busybox-init-base-files/etc/asound.conf

@@ -118,7 +118,7 @@ pcm.PlaybackRateDmix {
     }
     @args.PERIODSIZE {
         type integer
-        default 960 #1024
+        default 256 #1024
     }
     type plug
     slave.pcm {
@@ -135,7 +135,7 @@ pcm.PlaybackRateDmix {
                     rate        $SAMPLERATE
                     channels    $CHNNUM
                     period_size $PERIODSIZE
-                    periods 8
+                    periods 4
                 }
             }
             hooks.0 {