Update to latest tinyalsa

3bb114a pcm: add control for ASLA thresholds to pcm_open
ee99f21 include: make it easier to use this header from C++
89b3128 Makefile: Don't error out of clean if already clean
a14dad9 tinymix: Say if we can't open the mixer
49900f0 Merge pull request #3 from broonie/noprelink
ea019ef Merge pull request #2 from broonie/add-include

Change-Id: I110de23af1f43d2cefb134204cb0439a7fd4c1d0

Android.mk

@@ -6,6 +6,7 @@ LOCAL_SRC_FILES:= mixer.c pcm.c
 LOCAL_MODULE := libtinyalsa
 LOCAL_SHARED_LIBRARIES:= libcutils libutils
 LOCAL_MODULE_TAGS := optional
+LOCAL_PRELINK_MODULE := false
 
 include $(BUILD_SHARED_LIBRARY)
 

include/tinyalsa/asoundlib.h

@@ -31,6 +31,10 @@
 
 #include <sys/time.h>
 
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
 /*
  * PCM API
  */
@@ -55,6 +59,18 @@ struct pcm_config {
     unsigned int period_size;
     unsigned int period_count;
     enum pcm_format format;
+
+    /* Values to use for the ALSA start, stop and silence thresholds.  Setting
+     * any one of these values to 0 will cause the default tinyalsa values to be
+     * used instead.  Tinyalsa defaults are as follows.
+     *
+     * start_threshold   : period_count * period_size
+     * stop_threshold    : period_count * period_size
+     * silence_threshold : 0
+     */
+    unsigned int start_threshold;
+    unsigned int stop_threshold;
+    unsigned int silence_threshold;
 };
 
 /* Mixer control types */
@@ -149,4 +165,8 @@ int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string);
 int mixer_ctl_get_range_min(struct mixer_ctl *ctl);
 int mixer_ctl_get_range_max(struct mixer_ctl *ctl);
 
+#if defined(__cplusplus)
+}  /* extern "C" */
+#endif
+
 #endif

pcm.c

@@ -427,11 +427,21 @@ struct pcm *pcm_open(unsigned int card, unsigned int device,
     sparams.tstamp_mode = SNDRV_PCM_TSTAMP_ENABLE;
     sparams.period_step = 1;
     sparams.avail_min = 1;
-    sparams.start_threshold = config->period_count * config->period_size;
-    sparams.stop_threshold = config->period_count * config->period_size;
+
+    if (!config->start_threshold)
+        sparams.start_threshold = config->period_count * config->period_size;
+    else
+        sparams.start_threshold = config->start_threshold;
+
+    if (!config->stop_threshold)
+        sparams.stop_threshold = config->period_count * config->period_size;
+    else
+        sparams.stop_threshold = config->stop_threshold;
+
     sparams.xfer_align = config->period_size / 2; /* needed for old kernels */
     sparams.silence_size = 0;
-    sparams.silence_threshold = 0;
+    sparams.silence_threshold = config->silence_threshold;
+
 
     if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) {
         oops(pcm, errno, "cannot set sw params");

tinymix.c

@@ -41,6 +41,10 @@ int main(int argc, char **argv)
     struct mixer *mixer;
 
     mixer = mixer_open(0);
+    if (!mixer) {
+        fprintf(stderr, "Failed to open mixer\n");
+        return EXIT_FAILURE;
+    }
 
     if (argc == 1)
         tinymix_list_controls(mixer);