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 <linux/font.h>
18 #include <asm/types.h>
19 #include "fbcon.h"
20 #include "fbcon_rotate.h"
21 
22 static int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
23 {
24 	struct fbcon_ops *ops = info->fbcon_par;
25 	int len, err = 0;
26 	int s_cellsize, d_cellsize, i;
27 	const u8 *src;
28 	u8 *dst;
29 
30 	if (vc->vc_font.data == ops->fontdata &&
31 	    ops->p->con_rotate == ops->cur_rotate)
32 		goto finished;
33 
34 	src = ops->fontdata = vc->vc_font.data;
35 	ops->cur_rotate = ops->p->con_rotate;
36 	len = (!ops->p->userfont) ? 256 : FNTCHARCNT(src);
37 	s_cellsize = ((vc->vc_font.width + 7)/8) *
38 		vc->vc_font.height;
39 	d_cellsize = s_cellsize;
40 
41 	if (ops->rotate == FB_ROTATE_CW ||
42 	    ops->rotate == FB_ROTATE_CCW)
43 		d_cellsize = ((vc->vc_font.height + 7)/8) *
44 			vc->vc_font.width;
45 
46 	if (info->fbops->fb_sync)
47 		info->fbops->fb_sync(info);
48 
49 	if (ops->fd_size < d_cellsize * len) {
50 		dst = kmalloc_array(len, d_cellsize, GFP_KERNEL);
51 
52 		if (dst == NULL) {
53 			err = -ENOMEM;
54 			goto finished;
55 		}
56 
57 		ops->fd_size = d_cellsize * len;
58 		kfree(ops->fontbuffer);
59 		ops->fontbuffer = dst;
60 	}
61 
62 	dst = ops->fontbuffer;
63 	memset(dst, 0, ops->fd_size);
64 
65 	switch (ops->rotate) {
66 	case FB_ROTATE_UD:
67 		for (i = len; i--; ) {
68 			rotate_ud(src, dst, vc->vc_font.width,
69 				  vc->vc_font.height);
70 
71 			src += s_cellsize;
72 			dst += d_cellsize;
73 		}
74 		break;
75 	case FB_ROTATE_CW:
76 		for (i = len; i--; ) {
77 			rotate_cw(src, dst, vc->vc_font.width,
78 				  vc->vc_font.height);
79 			src += s_cellsize;
80 			dst += d_cellsize;
81 		}
82 		break;
83 	case FB_ROTATE_CCW:
84 		for (i = len; i--; ) {
85 			rotate_ccw(src, dst, vc->vc_font.width,
86 				   vc->vc_font.height);
87 			src += s_cellsize;
88 			dst += d_cellsize;
89 		}
90 		break;
91 	}
92 
93 finished:
94 	return err;
95 }
96 
97 void fbcon_set_rotate(struct fbcon_ops *ops)
98 {
99 	ops->rotate_font = fbcon_rotate_font;
100 
101 	switch(ops->rotate) {
102 	case FB_ROTATE_CW:
103 		fbcon_rotate_cw(ops);
104 		break;
105 	case FB_ROTATE_UD:
106 		fbcon_rotate_ud(ops);
107 		break;
108 	case FB_ROTATE_CCW:
109 		fbcon_rotate_ccw(ops);
110 		break;
111 	}
112 }
113 EXPORT_SYMBOL(fbcon_set_rotate);
114