From 561c0af8518dd8a2bac07284d306b0970c304f9f Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 5 Jun 2009 19:05:42 +0200
Subject: alsa: monitor device reservation status and resume automatically when
 device becomes unused

---
 src/modules/alsa/alsa-source.c | 65 ++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 62 insertions(+), 3 deletions(-)

(limited to 'src/modules/alsa/alsa-source.c')

diff --git a/src/modules/alsa/alsa-source.c b/src/modules/alsa/alsa-source.c
index 68f697d2..277b1103 100644
--- a/src/modules/alsa/alsa-source.c
+++ b/src/modules/alsa/alsa-source.c
@@ -114,6 +114,8 @@ struct userdata {
 
     pa_reserve_wrapper *reserve;
     pa_hook_slot *reserve_slot;
+    pa_reserve_monitor_wrapper *monitor;
+    pa_hook_slot *monitor_slot;
 };
 
 static void userdata_free(struct userdata *u);
@@ -183,6 +185,57 @@ static int reserve_init(struct userdata *u, const char *dname) {
     return 0;
 }
 
+static pa_hook_result_t monitor_cb(pa_reserve_monitor_wrapper *w, void* busy, struct userdata *u) {
+    pa_bool_t b;
+
+    pa_assert(w);
+    pa_assert(u);
+
+    b = PA_PTR_TO_UINT(busy) && !u->reserve;
+
+    pa_source_suspend(u->source, b, PA_SUSPEND_APPLICATION);
+    return PA_HOOK_OK;
+}
+
+static void monitor_done(struct userdata *u) {
+    pa_assert(u);
+
+    if (u->monitor_slot) {
+        pa_hook_slot_free(u->monitor_slot);
+        u->monitor_slot = NULL;
+    }
+
+    if (u->monitor) {
+        pa_reserve_monitor_wrapper_unref(u->monitor);
+        u->monitor = NULL;
+    }
+}
+
+static int reserve_monitor_init(struct userdata *u, const char *dname) {
+    char *rname;
+
+    pa_assert(u);
+    pa_assert(dname);
+
+    if (pa_in_system_mode())
+        return 0;
+
+    /* We are resuming, try to lock the device */
+    if (!(rname = pa_alsa_get_reserve_name(dname)))
+        return 0;
+
+    u->monitor = pa_reserve_monitor_wrapper_get(u->core, rname);
+    pa_xfree(rname);
+
+    if (!(u->monitor))
+        return -1;
+
+    pa_assert(!u->monitor_slot);
+    u->monitor_slot = pa_hook_connect(pa_reserve_monitor_wrapper_hook(u->monitor), PA_HOOK_NORMAL, (pa_hook_cb_t) monitor_cb, u);
+
+    return 0;
+}
+
 static void fix_min_sleep_wakeup(struct userdata *u) {
     size_t max_use, max_use_2;
     pa_assert(u);
@@ -1438,9 +1491,14 @@ pa_source *pa_alsa_source_new(pa_module *m, pa_modargs *ma, const char*driver, p
             pa_rtclock_usec(),
             FALSE);
 
-    if (reserve_init(u, pa_modargs_get_value(
-                             ma, "device_id",
-                             pa_modargs_get_value(ma, "device", DEFAULT_DEVICE))) < 0)
+    dev_id = pa_modargs_get_value(
+            ma, "device_id",
+            pa_modargs_get_value(ma, "device", DEFAULT_DEVICE));
+
+    if (reserve_init(u, dev_id) < 0)
+        goto fail;
+
+    if (reserve_monitor_init(u, dev_id) < 0)
         goto fail;
 
     b = use_mmap;
@@ -1676,6 +1734,7 @@ static void userdata_free(struct userdata *u) {
         pa_smoother_free(u->smoother);
 
     reserve_done(u);
+    monitor_done(u);
 
     pa_xfree(u->device_name);
     pa_xfree(u);
-- 
cgit