kernel/drivers/video/console/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
  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
 114 MODULE_AUTHOR("Antonino Daplas <adaplas@pol.net>");
 115 MODULE_DESCRIPTION("Console Rotation Support");
 116 MODULE_LICENSE("GPL");