1 #include <ctype.h>
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include <sys/mman.h>
5 #include <fcntl.h>
6 #include <string.h>
7 #include <termios.h>
8 #include <unistd.h>
9 #include <errno.h>
10 #include <linux/fb.h>
11
12
rotatefb_main(int argc,char * argv[])13 int rotatefb_main(int argc, char *argv[])
14 {
15 int c;
16 char *fbdev = "/dev/graphics/fb0";
17 int rotation = 0;
18 int fd;
19 int res;
20 struct fb_var_screeninfo fbinfo;
21
22 do {
23 c = getopt(argc, argv, "d:");
24 if (c == EOF)
25 break;
26 switch (c) {
27 case 'd':
28 fbdev = optarg;
29 break;
30 case '?':
31 fprintf(stderr, "%s: invalid option -%c\n",
32 argv[0], optopt);
33 exit(1);
34 }
35 } while (1);
36
37 if(optind + 1 != argc) {
38 fprintf(stderr, "%s: specify rotation\n", argv[0]);
39 exit(1);
40 }
41 rotation = atoi(argv[optind]);
42
43 fd = open(fbdev, O_RDWR);
44 if(fd < 0) {
45 fprintf(stderr, "cannot open %s\n", fbdev);
46 return 1;
47 }
48
49 res = ioctl(fd, FBIOGET_VSCREENINFO, &fbinfo);
50 if(res < 0) {
51 fprintf(stderr, "failed to get fbinfo: %s\n", strerror(errno));
52 return 1;
53 }
54 if((fbinfo.rotate ^ rotation) & 1) {
55 unsigned int xres = fbinfo.yres;
56 fbinfo.yres = fbinfo.xres;
57 fbinfo.xres = xres;
58 fbinfo.xres_virtual = fbinfo.xres;
59 fbinfo.yres_virtual = fbinfo.yres * 2;
60 if(fbinfo.yoffset == xres)
61 fbinfo.yoffset = fbinfo.yres;
62 }
63 fbinfo.rotate = rotation;
64 res = ioctl(fd, FBIOPUT_VSCREENINFO, &fbinfo);
65 if(res < 0) {
66 fprintf(stderr, "failed to set fbinfo: %s\n", strerror(errno));
67 return 1;
68 }
69
70 return 0;
71 }
72