fbcon_rotate.c

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/*
 *  linux/drivers/video/console/fbcon_rotate.c -- Software Rotation
 *
 *      Copyright (C) 2005 Antonino Daplas <adaplas @pol.net>
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License.  See the file COPYING in the main directory of this archive for
 *  more details.
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/fb.h>
#include <linux/vt_kern.h>
#include <linux/console.h>
#include <asm/types.h>
#include "fbcon.h"
#include "fbcon_rotate.h"

static int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
{
    struct fbcon_ops *ops = info->fbcon_par;
    int len, err = 0;
    int s_cellsize, d_cellsize, i;
    const u8 *src;
    u8 *dst;

    if (vc->vc_font.data == ops->fontdata &&
        ops->p->con_rotate == ops->cur_rotate)
        goto finished;

    src = ops->fontdata = vc->vc_font.data;
    ops->cur_rotate = ops->p->con_rotate;
    len = (!ops->p->userfont) ? 256 : FNTCHARCNT(src);
    s_cellsize = ((vc->vc_font.width + 7)/8) *
        vc->vc_font.height;
    d_cellsize = s_cellsize;

    if (ops->rotate == FB_ROTATE_CW ||
        ops->rotate == FB_ROTATE_CCW)
        d_cellsize = ((vc->vc_font.height + 7)/8) *
            vc->vc_font.width;

    if (info->fbops->fb_sync)
        info->fbops->fb_sync(info);

    if (ops->fd_size < d_cellsize * len) {
        dst = kmalloc(d_cellsize * len, GFP_KERNEL);

        if (dst == NULL) {
            err = -ENOMEM;
            goto finished;
        }

        ops->fd_size = d_cellsize * len;
        kfree(ops->fontbuffer);
        ops->fontbuffer = dst;
    }

    dst = ops->fontbuffer;
    memset(dst, 0, ops->fd_size);

    switch (ops->rotate) {
    case FB_ROTATE_UD:
        for (i = len; i--; ) {
            rotate_ud(src, dst, vc->vc_font.width,
                  vc->vc_font.height);

            src += s_cellsize;
            dst += d_cellsize;
        }
        break;
    case FB_ROTATE_CW:
        for (i = len; i--; ) {
            rotate_cw(src, dst, vc->vc_font.width,
                  vc->vc_font.height);
            src += s_cellsize;
            dst += d_cellsize;
        }
        break;
    case FB_ROTATE_CCW:
        for (i = len; i--; ) {
            rotate_ccw(src, dst, vc->vc_font.width,
                   vc->vc_font.height);
            src += s_cellsize;
            dst += d_cellsize;
        }
        break;
    }

finished:
    return err;
}

void fbcon_set_rotate(struct fbcon_ops *ops)
{
    ops->rotate_font = fbcon_rotate_font;

    switch(ops->rotate) {
    case FB_ROTATE_CW:
        fbcon_rotate_cw(ops);
        break;
    case FB_ROTATE_UD:
        fbcon_rotate_ud(ops);
        break;
    case FB_ROTATE_CCW:
        fbcon_rotate_ccw(ops);
        break;
    }
}
EXPORT_SYMBOL(fbcon_set_rotate);

MODULE_AUTHOR("Antonino Daplas <[email protected]>");
MODULE_DESCRIPTION("Console Rotation Support");
MODULE_LICENSE("GPL");