ALSA: xen-front: Implement Xen event channel handling

Handle Xen event channels:
  - create for all configured streams and publish
    corresponding ring references and event channels in Xen store,
    so backend can connect
  - implement event channels interrupt handlers
  - create and destroy event channels with respect to Xen bus state

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
index b52226cb30bc..9d0c92100c7b 100644
--- a/sound/xen/xen_snd_front.h
+++ b/sound/xen/xen_snd_front.h
@@ -13,9 +13,14 @@
 
 #include "xen_snd_front_cfg.h"
 
+struct xen_snd_front_evtchnl_pair;
+
 struct xen_snd_front_info {
 	struct xenbus_device *xb_dev;
 
+	int num_evt_pairs;
+	struct xen_snd_front_evtchnl_pair *evt_pairs;
+
 	struct xen_front_cfg_card cfg;
 };