[2/4]Allow hotplugging of primary DRM device

ui/ozone/platform/drm/gpu/drm_device_manager.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/ozone/platform/drm/gpu/drm_device_manager.h"
 
+#include "base/file_descriptor_posix.h"
+#include "base/single_thread_task_runner.h"
 #include "ui/ozone/platform/drm/gpu/drm_device.h"
+#include "ui/ozone/platform/drm/gpu/drm_device_generator.h"
 
 namespace ui {
 
+namespace {
+
+class FindByDevicePath {
+ public:
+  explicit FindByDevicePath(const base::FilePath& path) : path_(path) {}
+
+  bool operator()(const scoped_refptr<DrmDevice>& device) {
+    return device->device_path() == path_;
+  }
+
+ private:
+  base::FilePath path_;
+};
+
+}  // namespace
+
 DrmDeviceManager::DrmDeviceManager(
-    const scoped_refptr<DrmDevice>& primary_device)
-    : primary_device_(primary_device) {
+    scoped_ptr<DrmDeviceGenerator> drm_device_generator)
+    : drm_device_generator_(drm_device_generator.Pass()) {
 }
 
 DrmDeviceManager::~DrmDeviceManager() {
   DCHECK(drm_device_map_.empty());
 }
 
+bool DrmDeviceManager::AddDrmDevice(const base::FilePath& path,
+                                    const base::FileDescriptor& fd) {
+  base::AutoLock lock(lock_);
+  base::File file(fd.fd);
+  auto it =
+      std::find_if(devices_.begin(), devices_.end(), FindByDevicePath(path));
+  if (it != devices_.end()) {
+    VLOG(2) << "Got request to add existing device: " << path.value();
+    return false;
+  }
+
+  scoped_refptr<DrmDevice> device =
+      drm_device_generator_->CreateDevice(path, file.Pass());
+  if (!device) {
+    VLOG(2) << "Could not initialize DRM device for " << path.value();
+    return false;
+  }
+
+  if (io_task_runner_)
+    device->InitializeTaskRunner(io_task_runner_);
+
+  if (!primary_device_)
+    primary_device_ = device;
+
+  devices_.push_back(device);
+  return true;
+}
+
+void DrmDeviceManager::RemoveDrmDevice(const base::FilePath& path) {
+  base::AutoLock lock(lock_);
+  auto it =
+      std::find_if(devices_.begin(), devices_.end(), FindByDevicePath(path));
+  if (it == devices_.end()) {
+    VLOG(2) << "Got request to remove non-existent device: " << path.value();
+    return;
+  }
+
+  DCHECK_NE(primary_device_, *it);
+  devices_.erase(it);
+}
+
+void DrmDeviceManager::InitializeIOTaskRunner(
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner) {
+  DCHECK(!io_task_runner_);
+  io_task_runner_ = task_runner;
+  for (const auto& device : devices_)
+    device->InitializeTaskRunner(io_task_runner_);
+}
+
 void DrmDeviceManager::UpdateDrmDevice(gfx::AcceleratedWidget widget,
                                        const scoped_refptr<DrmDevice>& device) {
   base::AutoLock lock(lock_);
   drm_device_map_[widget] = device;
 }
 
 void DrmDeviceManager::RemoveDrmDevice(gfx::AcceleratedWidget widget) {
   base::AutoLock lock(lock_);
   auto it = drm_device_map_.find(widget);
+  // It shouldn't be possible to remove the primary device.
+  DCHECK_NE(it->second, primary_device_);
+
   if (it != drm_device_map_.end())
     drm_device_map_.erase(it);
 }
 
 scoped_refptr<DrmDevice> DrmDeviceManager::GetDrmDevice(
     gfx::AcceleratedWidget widget) {
   base::AutoLock lock(lock_);
   if (widget == gfx::kNullAcceleratedWidget)
     return primary_device_;
 
   auto it = drm_device_map_.find(widget);
   DCHECK(it != drm_device_map_.end())
       << "Attempting to get device for unknown widget " << widget;
   // If the widget isn't associated with a display (headless mode) we can
   // allocate buffers from any controller since they will never be scanned out.
   // Use the primary DRM device as a fallback when allocating these buffers.
   if (!it->second)
     return primary_device_;
 
   return it->second;
 }
 
+std::vector<scoped_refptr<DrmDevice>> DrmDeviceManager::GetDrmDevices() {
+  base::AutoLock lock(lock_);
+  return devices_;
+}
+
 }  // namespace ui