kernel-ark/drivers/video/fbcmap.c
Benjamin Herrenschmidt 7149437669 [PATCH] fbdev: Batch cmap changes at driver level
This patch adds to the fbdev interface a set_cmap callback that allow the
driver to "batch" palette changes.  This is useful for drivers like
radeonfb which might require lenghtly workarounds on palette accesses, thus
allowing to factor out those workarounds efficiently.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:22 -07:00

366 lines
8.3 KiB
C

/*
* 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 &&
!info->fbops->fb_setcmap))
return -EINVAL;
if (info->fbops->fb_setcmap)
return info->fbops->fb_setcmap(cmap, info);
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 &&
!info->fbops->fb_setcmap))
return -EINVAL;
/* If we can batch, do it */
if (info->fbops->fb_setcmap && cmap->len > 1) {
struct fb_cmap umap;
int size = cmap->len * sizeof(u16);
int rc;
memset(&umap, 0, sizeof(struct fb_cmap));
rc = fb_alloc_cmap(&umap, cmap->len, transp != NULL);
if (rc)
return rc;
if (copy_from_user(umap.red, red, size) ||
copy_from_user(umap.green, green, size) ||
copy_from_user(umap.blue, blue, size) ||
(transp && copy_from_user(umap.transp, transp, size))) {
rc = -EFAULT;
}
umap.start = start;
if (rc == 0)
rc = info->fbops->fb_setcmap(&umap, info);
fb_dealloc_cmap(&umap);
return rc;
}
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);