1 /*
2  *  linux/drivers/video/console/fbcon_rotate.c -- Software Rotation
3  *
4  *      Copyright (C) 2005 Antonino Daplas <adaplas @pol.net>
5  *
6  *  This file is subject to the terms and conditions of the GNU General Public
7  *  License.  See the file COPYING in the main directory of this archive for
8  *  more details.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/string.h>
14 #include <linux/fb.h>
15 #include <linux/vt_kern.h>
16 #include <linux/console.h>
17 #include <asm/types.h>
18 #include "fbcon.h"
19 #include "fbcon_rotate.h"
20 
21 static int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
22 {
23 	struct fbcon_ops *ops = info->fbcon_par;
24 	int len, err = 0;
25 	int s_cellsize, d_cellsize, i;
26 	const u8 *src;
27 	u8 *dst;
28 
29 	if (vc->vc_font.data == ops->fontdata &&
30 	    ops->p->con_rotate == ops->cur_rotate)
31 		goto finished;
32 
33 	src = ops->fontdata = vc->vc_font.data;
34 	ops->cur_rotate = ops->p->con_rotate;
35 	len = (!ops->p->userfont) ? 256 : FNTCHARCNT(src);
36 	s_cellsize = ((vc->vc_font.width + 7)/8) *
37 		vc->vc_font.height;
38 	d_cellsize = s_cellsize;
39 
40 	if (ops->rotate == FB_ROTATE_CW ||
41 	    ops->rotate == FB_ROTATE_CCW)
42 		d_cellsize = ((vc->vc_font.height + 7)/8) *
43 			vc->vc_font.width;
44 
45 	if (info->fbops->fb_sync)
46 		info->fbops->fb_sync(info);
47 
48 	if (ops->fd_size < d_cellsize * len) {
49 		dst = kmalloc(d_cellsize * len, GFP_KERNEL);
50 
51 		if (dst == NULL) {
52 			err = -ENOMEM;
53 			goto finished;
54 		}
55 
56 		ops->fd_size = d_cellsize * len;
57 		kfree(ops->fontbuffer);
58 		ops->fontbuffer = dst;
59 	}
60 
61 	dst = ops->fontbuffer;
62 	memset(dst, 0, ops->fd_size);
63 
64 	switch (ops->rotate) {
65 	case FB_ROTATE_UD:
66 		for (i = len; i--; ) {
67 			rotate_ud(src, dst, vc->vc_font.width,
68 				  vc->vc_font.height);
69 
70 			src += s_cellsize;
71 			dst += d_cellsize;
72 		}
73 		break;
74 	case FB_ROTATE_CW:
75 		for (i = len; i--; ) {
76 			rotate_cw(src, dst, vc->vc_font.width,
77 				  vc->vc_font.height);
78 			src += s_cellsize;
79 			dst += d_cellsize;
80 		}
81 		break;
82 	case FB_ROTATE_CCW:
83 		for (i = len; i--; ) {
84 			rotate_ccw(src, dst, vc->vc_font.width,
85 				   vc->vc_font.height);
86 			src += s_cellsize;
87 			dst += d_cellsize;
88 		}
89 		break;
90 	}
91 
92 finished:
93 	return err;
94 }
95 
96 void fbcon_set_rotate(struct fbcon_ops *ops)
97 {
98 	ops->rotate_font = fbcon_rotate_font;
99 
100 	switch(ops->rotate) {
101 	case FB_ROTATE_CW:
102 		fbcon_rotate_cw(ops);
103 		break;
104 	case FB_ROTATE_UD:
105 		fbcon_rotate_ud(ops);
106 		break;
107 	case FB_ROTATE_CCW:
108 		fbcon_rotate_ccw(ops);
109 		break;
110 	}
111 }
112 EXPORT_SYMBOL(fbcon_set_rotate);
113