If a card has been hot-plugged after pulseaudio start, alsa-lib still has
old configuration in memory, which doesn't have PCM definitions for the
new card. Thus, this error appears, and the device doesn't work:
I: [pulseaudio] (alsa-lib)confmisc.c: Unable to find definition 'cards.USB-Audio.pcm.front.0:CARD=0'
I: [pulseaudio] (alsa-lib)conf.c: function snd_func_refer returned error: No such file or directory
I: [pulseaudio] (alsa-lib)conf.c: Evaluate error: No such file or directory
I: [pulseaudio] (alsa-lib)pcm.c: Unknown PCM front:0
I: [pulseaudio] alsa-util.c: Error opening PCM device front:0: No such file or directory
The snd_config_update_free_global() function makes alsa-lib forget any
cached configuration and reparse all PCM definitions from scratch next
time it is told to open anything.
The trick has been copied from Phonon.
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=54029
Signed-off-by: Alexander E. Patrakov <patrakov@gmail.com>
b = use_mmap;
d = use_tsched;
+ /* Force ALSA to reread its configuration if module-alsa-card didn't
+ * do it for us. This matters if our device was hot-plugged after ALSA
+ * has already read its configuration - see
+ * https://bugs.freedesktop.org/show_bug.cgi?id=54029
+ */
+
+ if (!card)
+ snd_config_update_free_global();
+
if (mapping) {
if (!(dev_id = pa_modargs_get_value(ma, "device_id", NULL))) {
b = use_mmap;
d = use_tsched;
+ /* Force ALSA to reread its configuration if module-alsa-card didn't
+ * do it for us. This matters if our device was hot-plugged after ALSA
+ * has already read its configuration - see
+ * https://bugs.freedesktop.org/show_bug.cgi?id=54029
+ */
+
+ if (!card)
+ snd_config_update_free_global();
+
if (mapping) {
if (!(dev_id = pa_modargs_get_value(ma, "device_id", NULL))) {
}
pa_modargs_get_value_boolean(u->modargs, "use_ucm", &u->use_ucm);
+
+ /* Force ALSA to reread its configuration. This matters if our device
+ * was hot-plugged after ALSA has already read its configuration - see
+ * https://bugs.freedesktop.org/show_bug.cgi?id=54029
+ */
+
+ snd_config_update_free_global();
+
if (u->use_ucm && !pa_alsa_ucm_query_profiles(&u->ucm, u->alsa_card_index)) {
pa_log_info("Found UCM profiles");