xref: /linux/drivers/video/fbdev/core/fbcon_rotate.h (revision 48dea9a700c8728cc31a1dd44588b97578de86ee)
1 /*
2  *  linux/drivers/video/console/fbcon_rotate.h -- Software Display 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
8  *  for more details.
9  */
10 
11 #ifndef _FBCON_ROTATE_H
12 #define _FBCON_ROTATE_H
13 
14 #define GETVYRES(s,i) ({                           \
15         (s == SCROLL_REDRAW || s == SCROLL_MOVE) ? \
16         (i)->var.yres : (i)->var.yres_virtual; })
17 
18 #define GETVXRES(s,i) ({                           \
19         (s == SCROLL_REDRAW || s == SCROLL_MOVE || !(i)->fix.xpanstep) ? \
20         (i)->var.xres : (i)->var.xres_virtual; })
21 
22 
23 static inline int pattern_test_bit(u32 x, u32 y, u32 pitch, const char *pat)
24 {
25 	u32 tmp = (y * pitch) + x, index = tmp / 8,  bit = tmp % 8;
26 
27 	pat +=index;
28 	return (*pat) & (0x80 >> bit);
29 }
30 
31 static inline void pattern_set_bit(u32 x, u32 y, u32 pitch, char *pat)
32 {
33 	u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8;
34 
35 	pat += index;
36 
37 	(*pat) |= 0x80 >> bit;
38 }
39 
40 static inline void rotate_ud(const char *in, char *out, u32 width, u32 height)
41 {
42 	int i, j;
43 	int shift = (8 - (width % 8)) & 7;
44 
45 	width = (width + 7) & ~7;
46 
47 	for (i = 0; i < height; i++) {
48 		for (j = 0; j < width - shift; j++) {
49 			if (pattern_test_bit(j, i, width, in))
50 				pattern_set_bit(width - (1 + j + shift),
51 						height - (1 + i),
52 						width, out);
53 		}
54 
55 	}
56 }
57 
58 static inline void rotate_cw(const char *in, char *out, u32 width, u32 height)
59 {
60 	int i, j, h = height, w = width;
61 	int shift = (8 - (height % 8)) & 7;
62 
63 	width = (width + 7) & ~7;
64 	height = (height + 7) & ~7;
65 
66 	for (i = 0; i < h; i++) {
67 		for (j = 0; j < w; j++) {
68 			if (pattern_test_bit(j, i, width, in))
69 				pattern_set_bit(height - 1 - i - shift, j,
70 						height, out);
71 
72 		}
73 	}
74 }
75 
76 static inline void rotate_ccw(const char *in, char *out, u32 width, u32 height)
77 {
78 	int i, j, h = height, w = width;
79 	int shift = (8 - (width % 8)) & 7;
80 
81 	width = (width + 7) & ~7;
82 	height = (height + 7) & ~7;
83 
84 	for (i = 0; i < h; i++) {
85 		for (j = 0; j < w; j++) {
86 			if (pattern_test_bit(j, i, width, in))
87 				pattern_set_bit(i, width - 1 - j - shift,
88 						height, out);
89 		}
90 	}
91 }
92 
93 extern void fbcon_rotate_cw(struct fbcon_ops *ops);
94 extern void fbcon_rotate_ud(struct fbcon_ops *ops);
95 extern void fbcon_rotate_ccw(struct fbcon_ops *ops);
96 #endif
97