ALSA: oxfw: Add hwdep interface

[deliverable/linux.git] / sound / firewire / oxfw / oxfw-stream.c

diff --git a/sound/firewire/oxfw/oxfw-stream.c b/sound/firewire/oxfw/oxfw-stream.c
index a38b3c36facac0f30e89f5792b12627776e0a240..b77cf80f1678438fb51d7a871255c7c814ae4dbd 100644 (file)
--- a/sound/firewire/oxfw/oxfw-stream.c
+++ b/sound/firewire/oxfw/oxfw-stream.c
@@ -644,3 +644,42 @@ int snd_oxfw_stream_discover(struct snd_oxfw *oxfw)
 end:
        return err;
 }
+
+void snd_oxfw_stream_lock_changed(struct snd_oxfw *oxfw)
+{
+       oxfw->dev_lock_changed = true;
+       wake_up(&oxfw->hwdep_wait);
+}
+
+int snd_oxfw_stream_lock_try(struct snd_oxfw *oxfw)
+{
+       int err;
+
+       spin_lock_irq(&oxfw->lock);
+
+       /* user land lock this */
+       if (oxfw->dev_lock_count < 0) {
+               err = -EBUSY;
+               goto end;
+       }
+
+       /* this is the first time */
+       if (oxfw->dev_lock_count++ == 0)
+               snd_oxfw_stream_lock_changed(oxfw);
+       err = 0;
+end:
+       spin_unlock_irq(&oxfw->lock);
+       return err;
+}
+
+void snd_oxfw_stream_lock_release(struct snd_oxfw *oxfw)
+{
+       spin_lock_irq(&oxfw->lock);
+
+       if (WARN_ON(oxfw->dev_lock_count <= 0))
+               goto end;
+       if (--oxfw->dev_lock_count == 0)
+               snd_oxfw_stream_lock_changed(oxfw);
+end:
+       spin_unlock_irq(&oxfw->lock);
+}