mbed-os/drivers/source/usb/PolledQueue.cpp

94 lines
2.1 KiB
C++

/*
* Copyright (c) 2018-2019, Arm Limited and affiliates.
* SPDX-License-Identifier: Apache-2.0
*
* 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.
*/
#include "drivers/internal/PolledQueue.h"
#include "events/mbed_events.h"
#include "platform/Callback.h"
PolledQueue::PolledQueue(mbed::Callback<void()> cb): _cb(cb)
{
}
PolledQueue::~PolledQueue()
{
}
void PolledQueue::dispatch()
{
core_util_critical_section_enter();
uint64_t buf[MBED_MAX_TASK_SIZE / sizeof(uint64_t)];
while (true) {
// Atomically dequeue the task and copy the callback
TaskBase *task = _list.dequeue();
if (!task) {
break;
}
MBED_ASSERT(sizeof(buf) >= task_size(task));
TaskBase::run_callback_t callback = task_start(task, (uint8_t *)buf, sizeof(buf));
// Run the callback outside the critical section
core_util_critical_section_exit();
callback((uint8_t *)buf);
core_util_critical_section_enter();
// Finish
task_finish(task);
task = NULL;
}
core_util_critical_section_exit();
}
void PolledQueue::attach(mbed::Callback<void()> cb)
{
core_util_critical_section_enter();
_cb = cb;
core_util_critical_section_exit();
}
void PolledQueue::post(TaskBase *task)
{
core_util_critical_section_enter();
bool empty = _list.head() == NULL;
_list.remove(task);
_list.enqueue(task);
if (empty && _cb) {
_cb();
}
core_util_critical_section_exit();
}
void PolledQueue::cancel(TaskBase *task)
{
core_util_critical_section_enter();
_list.remove(task);
core_util_critical_section_exit();
}