zephyr/kernel/unified/event.c

79 lines
2.0 KiB
C

/*
* Copyright (c) 2016 Wind River Systems, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @file
* @brief kernel events.
*/
#include <kernel.h>
#include <nano_private.h>
#include <misc/debug/object_tracing_common.h>
#include <atomic.h>
#include <toolchain.h>
#include <sections.h>
void _k_event_deliver(struct k_work *work)
{
struct k_event *event = CONTAINER_OF(work, struct k_event, work_item);
while (1) {
if ((event->handler)(event) == 0) {
/* do nothing -- handler has processed the event */
} else {
/* pend the event */
k_sem_give(&event->sem);
}
if (atomic_dec(&event->send_count) == 1) {
/* have finished delivering events */
break;
}
}
}
void k_event_init(struct k_event *event, k_event_handler_t handler)
{
const struct k_work my_work_item = { NULL, _k_event_deliver, { 1 } };
event->handler = handler;
event->send_count = ATOMIC_INIT(0);
event->work_item = my_work_item;
k_sem_init(&event->sem, 0, 1);
SYS_TRACING_OBJ_INIT(event, event);
}
void k_event_send(struct k_event *event)
{
if (event->handler == K_EVT_IGNORE) {
/* ignore the event */
} else if (event->handler == K_EVT_DEFAULT) {
/* pend the event */
k_sem_give(&event->sem);
} else {
/* deliver the event */
if (atomic_inc(&event->send_count) == 0) {
/* add event's work item to system work queue */
k_work_submit_to_queue(&k_sys_work_q,
&event->work_item);
}
}
}
int k_event_recv(struct k_event *event, int32_t timeout)
{
return k_sem_take(&event->sem, timeout);
}