[Ozone] Adding HardwareDisplayController implementation

ui/gfx/ozone/impl/drm_wrapper_ozone.h

+// Copyright (c) 2013 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.
+
+#ifndef UI_GFX_OZONE_IMPL_DRM_WRAPPER_OZONE_H_
+#define UI_GFX_OZONE_IMPL_DRM_WRAPPER_OZONE_H_
+
+#include <stdint.h>
+
+#include "base/basictypes.h"
+
+typedef struct _drmModeCrtc drmModeCrtc;
+typedef struct _drmModeModeInfo drmModeModeInfo;
+
+namespace gfx {
+
+// Wraps DRM calls into a nice interface. Used to provide different
+// implementations of the DRM calls. For the actual implementation the DRM API
+// would be called. In unit tests this interface would be stubbed.
+class DrmWrapperOzone {
+ public:
+  DrmWrapperOzone(const char* device_path);
+  virtual ~DrmWrapperOzone();
+
+  // Get the CRTC state. This is generally used to save state before using the
+  // CRTC. When the user finishes using the CRTC, the user should restore the
+  // CRTC to it's initial state. Use |SetCrtc| to restore the state.
+  virtual drmModeCrtc* GetCrtc(uint32_t crtc_id);
+
+  // Frees the CRTC mode object.
+  virtual void FreeCrtc(drmModeCrtc* crtc);
+
+  // Used to configure CRTC with ID |crtc_id| to use the connector in
+  // |connectors|. The CRTC will be configured with mode |mode| and will display
+  // the framebuffer with ID |framebuffer|. Before being able to display the
+  // framebuffer, it should be registered with the CRTC using |AddFramebuffer|.
+  virtual bool SetCrtc(uint32_t crtc_id,
+                       uint32_t framebuffer,
+                       uint32_t* connectors,
+                       drmModeModeInfo* mode);
+
+  // Used to set a specific configuration to the CRTC. Normally this function
+  // would be called with a CRTC saved state (from |GetCrtc|) to restore it to
+  // its original configuration.
+  virtual bool SetCrtc(drmModeCrtc* crtc, uint32_t* connectors);
+
+  // Register a buffer with the CRTC. On successful registration, the CRTC will
+  // assign a framebuffer ID to |framebuffer|.
+  virtual bool AddFramebuffer(const drmModeModeInfo& mode,
+                              uint8_t depth,
+                              uint8_t bpp,
+                              uint32_t stride,
+                              uint32_t handle,
+                              uint32_t* framebuffer);
+
+  // Deregister the given |framebuffer|.
+  virtual bool RemoveFramebuffer(uint32_t framebuffer);
+
+  // Schedules a pageflip for CRTC |crtc_id|. This function will return
+  // immediately. Upon completion of the pageflip event, the CRTC will be
+  // displaying the buffer with ID |framebuffer| and will have a DRM event
+  // queued on |fd_|. |data| is a generic pointer to some information the user
+  // will receive when processing the pageflip event.
+  virtual bool PageFlip(uint32_t crtc_id, uint32_t framebuffer, void* data);
+
+  int get_fd() const { return fd_; }
+
+ protected:
+  // The file descriptor associated with this wrapper. All DRM operations will
+  // be performed using this FD.
+  int fd_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DrmWrapperOzone);
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_OZONE_IMPL_DRM_WRAPPER_OZONE_H_