Framebuffer的初始化

来源：互联网发布：网络老虎机mg出分技术编辑：程序博客网时间：2024/06/06 13:17

1 #include <stdio.h>
2 #include <fcntl.h>
3 #include <sys/ioctl.h>
4 #include <sys/types.h>
5 #include <linux/fb.h>
6 #include <stdlib.h>
7 #include <sys/mman.h>
8
9 #include "types.h"
10
11
12 int fb_init(FB_SCR *fb_scr)
13 {
14
15     struct fb_var_screeninfo fb_var;
16     int fd;
17     int ret;
18     int *p;
19
20     fd = open("/dev/fb0", O_RDWR);
21     if(fd == -1)
22     {
23         perror("fail to open");
24         exit(0);
25     }

26     ret = ioctl(fd, FBIOGET_VSCREENINFO, &fb_var);
27
28
29     printf("width: %d/thigh: %d/tbpp: %d/n", fb_var.xres, fb_var.yres, fb_var.bits_per_pixel);
30
31     p = mmap(NULL, fb_var.xres*fb_var.yres*fb_var.bits_per_pixel/32, PROT_WRITE|PROT_WRITE, MAP_SHARED, fd,     0);
32     if(p == NULL)
33     {
34         perror("fail to mmap");
35         exit(0);
36     }
37     fb_scr->x_res = fb_var.xres;
38     fb_scr->y_res = fb_var.yres;
39     fb_scr->bits_per_pixel = fb_var.bits_per_pixel;
40     fb_scr->mem = (void *)p;
41
42
43     close(fb_var);
44
45
46
47 }