hikey: Make the Hikey Bluetooth HAL independentlinaro-optee

Test: Bluetooth starts/stops
Change-Id: I8a8b113f3edcdb092c36fd7822aeabf900c0f0b3

1 files changed, 181 insertions, 0 deletions

diff --git a/bluetooth/async_fd_watcher.cc b/bluetooth/async_fd_watcher.cc
new file mode 100644
index 00000000..c4470d06
--- /dev/null
+++ b/bluetooth/async_fd_watcher.cc
@@ -0,0 +1,181 @@
+//
+// Copyright 2016 The Android Open Source Project
+//
+// 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 "async_fd_watcher.h"
+
+#include <algorithm>
+#include <atomic>
+#include <condition_variable>
+#include <map>
+#include <mutex>
+#include <thread>
+#include <vector>
+#include "fcntl.h"
+#include "sys/select.h"
+#include "unistd.h"
+
+static const int INVALID_FD = -1;
+
+namespace android {
+namespace hardware {
+namespace bluetooth {
+namespace async {
+
+int AsyncFdWatcher::WatchFdForNonBlockingReads(
+    int file_descriptor, const ReadCallback& on_read_fd_ready_callback) {
+  // Add file descriptor and callback
+  {
+    std::unique_lock<std::mutex> guard(internal_mutex_);
+    watched_fds_[file_descriptor] = on_read_fd_ready_callback;
+  }
+
+  // Start the thread if not started yet
+  return tryStartThread();
+}
+
+int AsyncFdWatcher::ConfigureTimeout(
+    const std::chrono::milliseconds timeout,
+    const TimeoutCallback& on_timeout_callback) {
+  // Add timeout and callback
+  {
+    std::unique_lock<std::mutex> guard(timeout_mutex_);
+    timeout_cb_ = on_timeout_callback;
+    timeout_ms_ = timeout;
+  }
+
+  notifyThread();
+  return 0;
+}
+
+void AsyncFdWatcher::StopWatchingFileDescriptors() { stopThread(); }
+
+AsyncFdWatcher::~AsyncFdWatcher() {}
+
+// Make sure to call this with at least one file descriptor ready to be
+// watched upon or the thread routine will return immediately
+int AsyncFdWatcher::tryStartThread() {
+  if (std::atomic_exchange(&running_, true)) return 0;
+
+  // Set up the communication channel
+  int pipe_fds[2];
+  if (pipe2(pipe_fds, O_NONBLOCK)) return -1;
+
+  notification_listen_fd_ = pipe_fds[0];
+  notification_write_fd_ = pipe_fds[1];
+
+  thread_ = std::thread([this]() { ThreadRoutine(); });
+  if (!thread_.joinable()) return -1;
+
+  return 0;
+}
+
+int AsyncFdWatcher::stopThread() {
+  if (!std::atomic_exchange(&running_, false)) return 0;
+
+  notifyThread();
+  if (std::this_thread::get_id() != thread_.get_id()) {
+    thread_.join();
+  }
+
+  {
+    std::unique_lock<std::mutex> guard(internal_mutex_);
+    watched_fds_.clear();
+  }
+
+  {
+    std::unique_lock<std::mutex> guard(timeout_mutex_);
+    timeout_cb_ = nullptr;
+  }
+
+  return 0;
+}
+
+int AsyncFdWatcher::notifyThread() {
+  uint8_t buffer[] = {0};
+  if (TEMP_FAILURE_RETRY(write(notification_write_fd_, &buffer, 1)) < 0) {
+    return -1;
+  }
+  return 0;
+}
+
+void AsyncFdWatcher::ThreadRoutine() {
+  while (running_) {
+    fd_set read_fds;
+    FD_ZERO(&read_fds);
+    FD_SET(notification_listen_fd_, &read_fds);
+    int max_read_fd = INVALID_FD;
+    for (auto& it : watched_fds_) {
+      FD_SET(it.first, &read_fds);
+      max_read_fd = std::max(max_read_fd, it.first);
+    }
+
+    struct timeval timeout;
+    struct timeval* timeout_ptr = NULL;
+    if (timeout_ms_ > std::chrono::milliseconds(0)) {
+      timeout.tv_sec = timeout_ms_.count() / 1000;
+      timeout.tv_usec = (timeout_ms_.count() % 1000) * 1000;
+      timeout_ptr = &timeout;
+    }
+
+    // Wait until there is data available to read on some FD.
+    int nfds = std::max(notification_listen_fd_, max_read_fd);
+    int retval = select(nfds + 1, &read_fds, NULL, NULL, timeout_ptr);
+
+    // There was some error.
+    if (retval < 0) continue;
+
+    // Timeout.
+    if (retval == 0) {
+      // Allow the timeout callback to modify the timeout.
+      TimeoutCallback saved_cb;
+      {
+        std::unique_lock<std::mutex> guard(timeout_mutex_);
+        if (timeout_ms_ > std::chrono::milliseconds(0)) saved_cb = timeout_cb_;
+      }
+      if (saved_cb != nullptr) saved_cb();
+      continue;
+    }
+
+    // Read data from the notification FD.
+    if (FD_ISSET(notification_listen_fd_, &read_fds)) {
+      char buffer[] = {0};
+      TEMP_FAILURE_RETRY(read(notification_listen_fd_, buffer, 1));
+      continue;
+    }
+
+    // Invoke the data ready callbacks if appropriate.
+    std::vector<decltype(watched_fds_)::value_type> saved_callbacks;
+    {
+      std::unique_lock<std::mutex> guard(internal_mutex_);
+      for (auto& it : watched_fds_) {
+        if (FD_ISSET(it.first, &read_fds)) {
+          saved_callbacks.push_back(it);
+        }
+      }
+    }
+
+    for (auto& it : saved_callbacks) {
+      if (it.second) {
+        it.second(it.first);
+      }
+    }
+  }
+}
+
+}  // namespace async
+}  // namespace bluetooth
+}  // namespace hardware
+}  // namespace android