Import Mbed OS hard-float snapshot

drivers/source/usb/AsyncOp.cpp

@@ -0,0 +1,146 @@
+/*
+ * 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 "AsyncOp.h"
+#include "mbed_critical.h"
+#include "mbed_assert.h"
+
+using namespace rtos;
+
+AsyncOp::AsyncOp():
+    _list(NULL), _wait(NULL), _aborted(false), _timeout(false)
+{
+
+}
+
+AsyncOp::AsyncOp(mbed::Callback<void()> &callback):
+    _list(NULL), _wait(NULL), _aborted(false), _timeout(false)
+{
+    _callback = callback;
+}
+
+AsyncOp::~AsyncOp()
+{
+    MBED_ASSERT(_list == NULL);
+}
+
+void AsyncOp::wait(rtos::Mutex *host_mutex, rtos::Kernel::Clock::duration_u32 rel_time)
+{
+    // Optimization so semaphore is only created if necessary
+    core_util_critical_section_enter();
+    bool done = _list == NULL;
+    core_util_critical_section_exit();
+    if (done) {
+        return;
+    }
+
+    // Construct semaphore to wait on
+    Semaphore sem(0);
+
+    core_util_critical_section_enter();
+    done = _list == NULL;
+    // Wait is only allowed to be called from one thread
+    MBED_ASSERT(_wait == NULL);
+    _wait = &sem;
+    core_util_critical_section_exit();
+
+    if (done) {
+        // Operation was signaled before semaphore was set
+        return;
+    }
+
+    if (sem.try_acquire_for(rel_time)) {
+        // Operation completion signaled semaphore
+        return;
+    }
+
+    _host_lock(host_mutex);
+    _abort(true);
+    _host_unlock(host_mutex);
+}
+
+void AsyncOp::abort()
+{
+    // Host lock must be held
+
+    _abort(false);
+}
+
+void AsyncOp::complete()
+{
+    core_util_critical_section_enter();
+
+    mbed::Callback<void()> cb = _callback;
+    _callback = nullptr;
+    _list = nullptr;
+    if (_wait != nullptr) {
+        _wait->release();
+    }
+
+    core_util_critical_section_exit();
+
+    if (cb) {
+        cb();
+    }
+}
+
+bool AsyncOp::timeout()
+{
+    core_util_critical_section_enter();
+
+    bool ret = _timeout;
+
+    core_util_critical_section_exit();
+    return ret;
+}
+
+void AsyncOp::_abort(bool timeout)
+{
+    // host lock must be held
+
+    core_util_critical_section_enter();
+    OperationListBase *list = _list;
+    if (list) {
+        _callback = nullptr;
+        _aborted = true;
+        _wait = nullptr;
+        _timeout = timeout;
+        _list = nullptr;
+    }
+    core_util_critical_section_exit();
+    if (list) {
+        list->remove(this);
+    }
+}
+
+void AsyncOp::_host_lock(rtos::Mutex *host_mutex)
+{
+    if (host_mutex) {
+        host_mutex->lock();
+    } else {
+        core_util_critical_section_enter();
+    }
+}
+
+void AsyncOp::_host_unlock(rtos::Mutex *host_mutex)
+{
+    if (host_mutex) {
+        host_mutex->unlock();
+    } else {
+        core_util_critical_section_exit();
+    }
+}