1 /**
2 *lcd.c
3 */
4 #include <unistd.h>
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <fcntl.h>
8 #include <string.h>
9 #include <linux/fb.h>
10 #include <sys/mman.h>
11 #include <sys/ioctl.h>
12 #include <arpa/inet.h>
13 #include "type.h"
14 #include "lcd.h"
15
16
17 lcd_t lcd;
18
19 s32 lcd_fb_init(void)
20 {
21 //打开显示设备
22 lcd.fd = open("/dev/fb0", O_RDWR);
23 if (!lcd.fd)
24 {
25 printf("Error: open /dev/fb0\n");
26 return -1;
27 }
28
29 //get fix information
30 if (ioctl(lcd.fd, FBIOGET_FSCREENINFO, &lcd.finfo))
31 {
32 printf("Error: get fix info");
33 return -1;
34 }
35
36 //get variable information
37 if (ioctl(lcd.fd, FBIOGET_VSCREENINFO, &lcd.vinfo))
38 {
39 printf("Error: get var info");
40 return -1;
41 }
42
43 lcd.vinfo.bits_per_pixel = 16;
44 //lcd screen byte size
45 lcd.screensize = lcd.vinfo.xres * lcd.vinfo.bits_per_pixel / 8 +
46 lcd.vinfo.yres *lcd.vinfo.xres;
47
48 //对象映射
49 lcd.fbp = (u8 *)mmap(0, lcd.screensize, PROT_READ | PROT_WRITE, MAP_SHARED, lcd.fd, 0);
50 if ((int)lcd.fbp == -1)
51 {
52 printf("Error: mmap\n");
53 return -1;
54 }
55 }
56 void lcd_fb_release(void)
57 {
58 /*释放缓冲区，关闭设备*/
59 munmap(lcd.fbp, lcd.screensize);
60 close(lcd.fd);
61 return ;
62 }
63
64 void lcd_fb_clear(void)
65 {
66 memset(lcd.fbp, 0, lcd.screensize);
67 return ;
68 }
69
70 void lcd_fb_info(void)
71 {
72 printf("xres: %d\n", lcd.vinfo.xres);
73 printf("yres: %d\n", lcd.vinfo.yres);
74 printf("screensize: %d\n", lcd.screensize);
75 printf("bits_per_pixel: %d\n", lcd.vinfo.bits_per_pixel);
76 return;
77 }
78
79
80 void lcd_fb_put_pixel(u16 x, u16 y, color_t color)
81 {
82 u32 location;
83 if (x > lcd.vinfo.xres - 1) x = lcd.vinfo.xres - 1;
84 if (y > lcd.vinfo.yres - 1) y = lcd.vinfo.yres - 1;
85 location = x * lcd.vinfo.bits_per_pixel / 8 + y * lcd.vinfo.xres;
86 if (y%2) location -= (lcd.vinfo.yres + 80);/*if you know why? please tell me*/
87
88 if (32 == lcd.vinfo.bits_per_pixel)
89 {
90 *((u8*) (lcd.fbp + location)) = color.r;
91 *((u8*) (lcd.fbp + location + 1)) = color.g;
92 *((u8*) (lcd.fbp + location + 2)) = color.b;
93 *((u8*) (lcd.fbp + location + 3)) = 0;/*transplite, unused*/
94 }
95 else if (16 == lcd.vinfo.bits_per_pixel)
96 {
97 *((u16*)(lcd.fbp + location)) = (u16)(color.r << 11 | color.g << 5 |color.b );
98 }
99 else
100 {
101 ;//
102 }103 }
104
105 void lcd_fb_draw_line(u16 x1, u16 y1, u16 x2, u16 y2, color_t color)
106 {
107 int i = 0;
108 int d = 0;
109 if (abs(y2 - y1) > abs(x2 - x1))
110 {
111 d = (y2 > y1) ? 1 : -1;
112 for (i = y1; i != y2; i +=d)
113 {
114 lcd_fb_put_pixel(x1 + (i - y1) * (x2 - x1) / (y2 - y1), i, color);
115 }
116 }
117 else
118 {
119 d = (x2 > x1) ? 1 : -1;
120 for (i = x1; i != x2; i+=d)
121 {
122 lcd_fb_put_pixel(i, y1 + (i - x1) * (y2 - y1) / (x2 - x1), color);
123 }
124 }
125 }
frambuffer lcd.c,码迷,mamicode.com
时间： 2024-12-09 23:02:38