drivers: xen: return hypercall results from notify_evtchn

Xen event channel notification may fail during hypervisor handling,
so it will be good for user to have a possibility to check results.

Previous implementation ignored hypervisor return code, now it will be
passed to caller.

Signed-off-by: Dmytro Firsov <dmytro_firsov@epam.com>

Author: firscity

drivers/xen/events.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021 EPAM Systems
+ * Copyright (c) 2021-2025 EPAM Systems
  * Copyright (c) 2022 Arm Limited (or its affiliates). All rights reserved.
  *
  * SPDX-License-Identifier: Apache-2.0
@@ -111,7 +111,7 @@ int evtchn_set_priority(evtchn_port_t port, uint32_t priority)
 	return HYPERVISOR_event_channel_op(EVTCHNOP_set_priority, &set);
 }
 
-void notify_evtchn(evtchn_port_t port)
+int notify_evtchn(evtchn_port_t port)
 {
 	struct evtchn_send send;
 
@@ -121,7 +121,7 @@ void notify_evtchn(evtchn_port_t port)
 
 	send.port = port;
 
-	HYPERVISOR_event_channel_op(EVTCHNOP_send, &send);
+	return HYPERVISOR_event_channel_op(EVTCHNOP_send, &send);
 }
 
 int bind_event_channel(evtchn_port_t port, evtchn_cb_t cb, void *data)

include/zephyr/xen/events.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021 EPAM Systems
+ * Copyright (c) 2021-2025 EPAM Systems
  * Copyright (c) 2022 Arm Limited (or its affiliates). All rights reserved.
  *
  * SPDX-License-Identifier: Apache-2.0
@@ -26,7 +26,7 @@ typedef struct event_channel_handle evtchn_handle_t;
 int evtchn_status(evtchn_status_t *status);
 int evtchn_close(evtchn_port_t port);
 int evtchn_set_priority(evtchn_port_t port, uint32_t priority);
-void notify_evtchn(evtchn_port_t port);
+int notify_evtchn(evtchn_port_t port);
 
 /*
  * Allocate event-channel between caller and remote domain