fbcon_rotate.c

 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
21int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
22{
23	struct fbcon_par *par = 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 == par->fontdata &&
30	    par->p->con_rotate == par->cur_rotate)
31		goto finished;
32
33	src = par->fontdata = vc->vc_font.data;
34	par->cur_rotate = par->p->con_rotate;
35	len = vc->vc_font.charcount;
36	s_cellsize = ((vc->vc_font.width + 7)/8) *
37		vc->vc_font.height;
38	d_cellsize = s_cellsize;
39
40	if (par->rotate == FB_ROTATE_CW ||
41	    par->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 (par->fd_size < d_cellsize * len) {
49		dst = kmalloc_array(len, d_cellsize, GFP_KERNEL);
50
51		if (dst == NULL) {
52			err = -ENOMEM;
53			goto finished;
54		}
55
56		par->fd_size = d_cellsize * len;
57		kfree(par->fontbuffer);
58		par->fontbuffer = dst;
59	}
60
61	dst = par->fontbuffer;
62	memset(dst, 0, par->fd_size);
63
64	switch (par->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
92finished:
93	return err;
94}