alsa: Allow channel count probe on open by mapping

This allows opening a PCM given a mapping to work even if we don't have
a channel count for the device up-front.

diff --git a/src/modules/alsa/alsa-util.c b/src/modules/alsa/alsa-util.c
index fbdf4760a83466f272aeb03e72d934649b7afcf1..bb4e307ccb96b9e6ee687f4a145e5914a94b4e1e 100644 (file)
--- a/src/modules/alsa/alsa-util.c
+++ b/src/modules/alsa/alsa-util.c
@@ -627,7 +627,7 @@ snd_pcm_t *pa_alsa_open_by_device_id_mapping(
             tsched_size,
             use_mmap,
             use_tsched,
-            TRUE);
+            pa_channel_map_valid(&m->channel_map) /* Query the channel count if we don't know what we want */);
 
     if (!pcm_handle)
         return NULL;