linux/drivers/video/fbcmap.c

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/*
* linux/drivers/video/fbcmap.c -- Colormap handling for frame buffer devices
*
* Created 15 Jun 1997 by Geert Uytterhoeven
*
* 2001 - Documented with DocBook
* - Brad Douglas <brad@neruo.com>
*
* 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/string.h>
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/fb.h>
#include <linux/slab.h>
#include <asm/uaccess.h>
static u16 red2[] = {
0x0000, 0xaaaa
};
static u16 green2[] = {
0x0000, 0xaaaa
};
static u16 blue2[] = {
0x0000, 0xaaaa
};
static u16 red4[] = {
0x0000, 0xaaaa, 0x5555, 0xffff
};
static u16 green4[] = {
0x0000, 0xaaaa, 0x5555, 0xffff
};
static u16 blue4[] = {
0x0000, 0xaaaa, 0x5555, 0xffff
};
static u16 red8[] = {
0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa
};
static u16 green8[] = {
0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa
};
static u16 blue8[] = {
0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa
};
static u16 red16[] = {
0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa,
0x5555, 0x5555, 0x5555, 0x5555, 0xffff, 0xffff, 0xffff, 0xffff
};
static u16 green16[] = {
0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa,
0x5555, 0x5555, 0xffff, 0xffff, 0x5555, 0x5555, 0xffff, 0xffff
};
static u16 blue16[] = {
0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa,
0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff
};
static struct fb_cmap default_2_colors = {
0, 2, red2, green2, blue2, NULL
};
static struct fb_cmap default_8_colors = {
0, 8, red8, green8, blue8, NULL
};
static struct fb_cmap default_4_colors = {
0, 4, red4, green4, blue4, NULL
};
static struct fb_cmap default_16_colors = {
0, 16, red16, green16, blue16, NULL
};
/**
* fb_alloc_cmap - allocate a colormap
* @cmap: frame buffer colormap structure
* @len: length of @cmap
* @transp: boolean, 1 if there is transparency, 0 otherwise
*
* Allocates memory for a colormap @cmap. @len is the
* number of entries in the palette.
*
* Returns -1 errno on error, or zero on success.
*
*/
int fb_alloc_cmap(struct fb_cmap *cmap, int len, int transp)
{
int size = len*sizeof(u16);
if (cmap->len != len) {
fb_dealloc_cmap(cmap);
if (!len)
return 0;
if (!(cmap->red = kmalloc(size, GFP_ATOMIC)))
goto fail;
if (!(cmap->green = kmalloc(size, GFP_ATOMIC)))
goto fail;
if (!(cmap->blue = kmalloc(size, GFP_ATOMIC)))
goto fail;
if (transp) {
if (!(cmap->transp = kmalloc(size, GFP_ATOMIC)))
goto fail;
} else
cmap->transp = NULL;
}
cmap->start = 0;
cmap->len = len;
fb_copy_cmap(fb_default_cmap(len), cmap);
return 0;
fail:
fb_dealloc_cmap(cmap);
return -1;
}
/**
* fb_dealloc_cmap - deallocate a colormap
* @cmap: frame buffer colormap structure
*
* Deallocates a colormap that was previously allocated with
* fb_alloc_cmap().
*
*/
void fb_dealloc_cmap(struct fb_cmap *cmap)
{
kfree(cmap->red);
kfree(cmap->green);
kfree(cmap->blue);
kfree(cmap->transp);
cmap->red = cmap->green = cmap->blue = cmap->transp = NULL;
cmap->len = 0;
}
/**
* fb_copy_cmap - copy a colormap
* @from: frame buffer colormap structure
* @to: frame buffer colormap structure
*
* Copy contents of colormap from @from to @to.
*/
int fb_copy_cmap(struct fb_cmap *from, struct fb_cmap *to)
{
int tooff = 0, fromoff = 0;
int size;
if (to->start > from->start)
fromoff = to->start - from->start;
else
tooff = from->start - to->start;
size = to->len - tooff;
if (size > (int) (from->len - fromoff))
size = from->len - fromoff;
if (size <= 0)
return -EINVAL;
size *= sizeof(u16);
memcpy(to->red+tooff, from->red+fromoff, size);
memcpy(to->green+tooff, from->green+fromoff, size);
memcpy(to->blue+tooff, from->blue+fromoff, size);
if (from->transp && to->transp)
memcpy(to->transp+tooff, from->transp+fromoff, size);
return 0;
}
int fb_cmap_to_user(struct fb_cmap *from, struct fb_cmap_user *to)
{
int tooff = 0, fromoff = 0;
int size;
if (to->start > from->start)
fromoff = to->start - from->start;
else
tooff = from->start - to->start;
size = to->len - tooff;
if (size > (int) (from->len - fromoff))
size = from->len - fromoff;
if (size <= 0)
return -EINVAL;
size *= sizeof(u16);
if (copy_to_user(to->red+tooff, from->red+fromoff, size))
return -EFAULT;
if (copy_to_user(to->green+tooff, from->green+fromoff, size))
return -EFAULT;
if (copy_to_user(to->blue+tooff, from->blue+fromoff, size))
return -EFAULT;
if (from->transp && to->transp)
if (copy_to_user(to->transp+tooff, from->transp+fromoff, size))
return -EFAULT;
return 0;
}
/**
* fb_set_cmap - set the colormap
* @cmap: frame buffer colormap structure
* @info: frame buffer info structure
*
* Sets the colormap @cmap for a screen of device @info.
*
* Returns negative errno on error, or zero on success.
*
*/
int fb_set_cmap(struct fb_cmap *cmap, struct fb_info *info)
{
int i, start;
u16 *red, *green, *blue, *transp;
u_int hred, hgreen, hblue, htransp = 0xffff;
red = cmap->red;
green = cmap->green;
blue = cmap->blue;
transp = cmap->transp;
start = cmap->start;
if (start < 0 || !info->fbops->fb_setcolreg)
return -EINVAL;
for (i = 0; i < cmap->len; i++) {
hred = *red++;
hgreen = *green++;
hblue = *blue++;
if (transp)
htransp = *transp++;
if (info->fbops->fb_setcolreg(start++,
hred, hgreen, hblue, htransp,
info))
break;
}
return 0;
}
int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info)
{
int i, start;
u16 __user *red, *green, *blue, *transp;
u_int hred, hgreen, hblue, htransp = 0xffff;
red = cmap->red;
green = cmap->green;
blue = cmap->blue;
transp = cmap->transp;
start = cmap->start;
if (start < 0 || !info->fbops->fb_setcolreg)
return -EINVAL;
for (i = 0; i < cmap->len; i++, red++, blue++, green++) {
if (get_user(hred, red) ||
get_user(hgreen, green) ||
get_user(hblue, blue) ||
(transp && get_user(htransp, transp)))
return -EFAULT;
if (info->fbops->fb_setcolreg(start++,
hred, hgreen, hblue, htransp,
info))
return 0;
if (transp)
transp++;
}
return 0;
}
/**
* fb_default_cmap - get default colormap
* @len: size of palette for a depth
*
* Gets the default colormap for a specific screen depth. @len
* is the size of the palette for a particular screen depth.
*
* Returns pointer to a frame buffer colormap structure.
*
*/
struct fb_cmap *fb_default_cmap(int len)
{
if (len <= 2)
return &default_2_colors;
if (len <= 4)
return &default_4_colors;
if (len <= 8)
return &default_8_colors;
return &default_16_colors;
}
/**
* fb_invert_cmaps - invert all defaults colormaps
*
* Invert all default colormaps.
*
*/
void fb_invert_cmaps(void)
{
u_int i;
for (i = 0; i < 2; i++) {
red2[i] = ~red2[i];
green2[i] = ~green2[i];
blue2[i] = ~blue2[i];
}
for (i = 0; i < 4; i++) {
red4[i] = ~red4[i];
green4[i] = ~green4[i];
blue4[i] = ~blue4[i];
}
for (i = 0; i < 8; i++) {
red8[i] = ~red8[i];
green8[i] = ~green8[i];
blue8[i] = ~blue8[i];
}
for (i = 0; i < 16; i++) {
red16[i] = ~red16[i];
green16[i] = ~green16[i];
blue16[i] = ~blue16[i];
}
}
/*
* Visible symbols for modules
*/
EXPORT_SYMBOL(fb_alloc_cmap);
EXPORT_SYMBOL(fb_dealloc_cmap);
EXPORT_SYMBOL(fb_copy_cmap);
EXPORT_SYMBOL(fb_set_cmap);
EXPORT_SYMBOL(fb_default_cmap);
EXPORT_SYMBOL(fb_invert_cmaps);