1 /*
2  * Copyright (C) 2017 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <linux/fb.h>
20 #include <stddef.h>
21 #include <stdint.h>
22 
23 #include <memory>
24 #include <vector>
25 
26 #include <android-base/unique_fd.h>
27 
28 #include "graphics.h"
29 #include "minui/minui.h"
30 
31 class GRSurfaceFbdev : public GRSurface {
32  public:
33   // Creates and returns a GRSurfaceFbdev instance, or nullptr on error.
34   static std::unique_ptr<GRSurfaceFbdev> Create(size_t width, size_t height, size_t row_bytes,
35                                                 size_t pixel_bytes);
36 
data()37   uint8_t* data() override {
38     return buffer_;
39   }
40 
41  protected:
42   using GRSurface::GRSurface;
43 
44  private:
45   friend class MinuiBackendFbdev;
46 
47   // Points to the start of the buffer: either the mmap'd framebuffer or one allocated in-memory.
48   uint8_t* buffer_{ nullptr };
49 };
50 
51 class MinuiBackendFbdev : public MinuiBackend {
52  public:
53   MinuiBackendFbdev() = default;
54   ~MinuiBackendFbdev() override = default;
55 
56   GRSurface* Init() override;
57   GRSurface* Flip() override;
58   void Blank(bool) override;
59   void Blank(bool blank, DrmConnector index) override;
60   bool HasMultipleConnectors() override;
61 
62  private:
63   void SetDisplayedFramebuffer(size_t n);
64 
65   std::unique_ptr<GRSurfaceFbdev> gr_framebuffer[2];
66   // Points to the current surface (i.e. one of the two gr_framebuffer's).
67   GRSurfaceFbdev* gr_draw{ nullptr };
68   bool double_buffered;
69   std::vector<uint8_t> memory_buffer;
70   size_t displayed_buffer{ 0 };
71   fb_var_screeninfo vi;
72   android::base::unique_fd fb_fd;
73 };
74