2 * linux/drivers/video/fbcmap.c -- Colormap handling for frame buffer devices
4 * Created 15 Jun 1997 by Geert Uytterhoeven
6 * 2001 - Documented with DocBook
7 * - Brad Douglas <brad@neruo.com>
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file COPYING in the main directory of this archive for
14 #include <linux/string.h>
15 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/uaccess.h>
20 static u16 red2[] __read_mostly = {
23 static u16 green2[] __read_mostly = {
26 static u16 blue2[] __read_mostly = {
30 static u16 red4[] __read_mostly = {
31 0x0000, 0xaaaa, 0x5555, 0xffff
33 static u16 green4[] __read_mostly = {
34 0x0000, 0xaaaa, 0x5555, 0xffff
36 static u16 blue4[] __read_mostly = {
37 0x0000, 0xaaaa, 0x5555, 0xffff
40 static u16 red8[] __read_mostly = {
41 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa
43 static u16 green8[] __read_mostly = {
44 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa
46 static u16 blue8[] __read_mostly = {
47 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa
50 static u16 red16[] __read_mostly = {
51 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa,
52 0x5555, 0x5555, 0x5555, 0x5555, 0xffff, 0xffff, 0xffff, 0xffff
54 static u16 green16[] __read_mostly = {
55 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa,
56 0x5555, 0x5555, 0xffff, 0xffff, 0x5555, 0x5555, 0xffff, 0xffff
58 static u16 blue16[] __read_mostly = {
59 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa,
60 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff
63 static const struct fb_cmap default_2_colors = {
64 .len=2, .red=red2, .green=green2, .blue=blue2
66 static const struct fb_cmap default_8_colors = {
67 .len=8, .red=red8, .green=green8, .blue=blue8
69 static const struct fb_cmap default_4_colors = {
70 .len=4, .red=red4, .green=green4, .blue=blue4
72 static const struct fb_cmap default_16_colors = {
73 .len=16, .red=red16, .green=green16, .blue=blue16
79 * fb_alloc_cmap_gfp - allocate a colormap
80 * @cmap: frame buffer colormap structure
81 * @len: length of @cmap
82 * @transp: boolean, 1 if there is transparency, 0 otherwise
83 * @flags: flags for kmalloc memory allocation
85 * Allocates memory for a colormap @cmap. @len is the
86 * number of entries in the palette.
88 * Returns negative errno on error, or zero on success.
92 int fb_alloc_cmap_gfp(struct fb_cmap *cmap, int len, int transp, gfp_t flags)
94 int size = len * sizeof(u16);
97 flags |= __GFP_NOWARN;
99 if (cmap->len != len) {
100 fb_dealloc_cmap(cmap);
104 cmap->red = kzalloc(size, flags);
107 cmap->green = kzalloc(size, flags);
110 cmap->blue = kzalloc(size, flags);
114 cmap->transp = kzalloc(size, flags);
123 ret = fb_copy_cmap(fb_default_cmap(len), cmap);
129 fb_dealloc_cmap(cmap);
133 int fb_alloc_cmap(struct fb_cmap *cmap, int len, int transp)
135 return fb_alloc_cmap_gfp(cmap, len, transp, GFP_ATOMIC);
139 * fb_dealloc_cmap - deallocate a colormap
140 * @cmap: frame buffer colormap structure
142 * Deallocates a colormap that was previously allocated with
147 void fb_dealloc_cmap(struct fb_cmap *cmap)
154 cmap->red = cmap->green = cmap->blue = cmap->transp = NULL;
159 * fb_copy_cmap - copy a colormap
160 * @from: frame buffer colormap structure
161 * @to: frame buffer colormap structure
163 * Copy contents of colormap from @from to @to.
166 int fb_copy_cmap(const struct fb_cmap *from, struct fb_cmap *to)
168 unsigned int tooff = 0, fromoff = 0;
171 if (to->start > from->start)
172 fromoff = to->start - from->start;
174 tooff = from->start - to->start;
175 if (fromoff >= from->len || tooff >= to->len)
178 size = min_t(size_t, to->len - tooff, from->len - fromoff);
183 memcpy(to->red+tooff, from->red+fromoff, size);
184 memcpy(to->green+tooff, from->green+fromoff, size);
185 memcpy(to->blue+tooff, from->blue+fromoff, size);
186 if (from->transp && to->transp)
187 memcpy(to->transp+tooff, from->transp+fromoff, size);
191 int fb_cmap_to_user(const struct fb_cmap *from, struct fb_cmap_user *to)
193 unsigned int tooff = 0, fromoff = 0;
196 if (to->start > from->start)
197 fromoff = to->start - from->start;
199 tooff = from->start - to->start;
200 if (fromoff >= from->len || tooff >= to->len)
203 size = min_t(size_t, to->len - tooff, from->len - fromoff);
208 if (copy_to_user(to->red+tooff, from->red+fromoff, size))
210 if (copy_to_user(to->green+tooff, from->green+fromoff, size))
212 if (copy_to_user(to->blue+tooff, from->blue+fromoff, size))
214 if (from->transp && to->transp)
215 if (copy_to_user(to->transp+tooff, from->transp+fromoff, size))
221 * fb_set_cmap - set the colormap
222 * @cmap: frame buffer colormap structure
223 * @info: frame buffer info structure
225 * Sets the colormap @cmap for a screen of device @info.
227 * Returns negative errno on error, or zero on success.
231 int fb_set_cmap(struct fb_cmap *cmap, struct fb_info *info)
233 int i, start, rc = 0;
234 u16 *red, *green, *blue, *transp;
235 u_int hred, hgreen, hblue, htransp = 0xffff;
240 transp = cmap->transp;
243 if (start < 0 || (!info->fbops->fb_setcolreg &&
244 !info->fbops->fb_setcmap))
246 if (info->fbops->fb_setcmap) {
247 rc = info->fbops->fb_setcmap(cmap, info);
249 for (i = 0; i < cmap->len; i++) {
255 if (info->fbops->fb_setcolreg(start++,
262 fb_copy_cmap(cmap, &info->cmap);
267 int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info)
269 int rc, size = cmap->len * sizeof(u16);
272 if (size < 0 || size < cmap->len)
275 memset(&umap, 0, sizeof(struct fb_cmap));
276 rc = fb_alloc_cmap_gfp(&umap, cmap->len, cmap->transp != NULL,
280 if (copy_from_user(umap.red, cmap->red, size) ||
281 copy_from_user(umap.green, cmap->green, size) ||
282 copy_from_user(umap.blue, cmap->blue, size) ||
283 (cmap->transp && copy_from_user(umap.transp, cmap->transp, size))) {
287 umap.start = cmap->start;
289 rc = fb_set_cmap(&umap, info);
290 unlock_fb_info(info);
292 fb_dealloc_cmap(&umap);
297 * fb_default_cmap - get default colormap
298 * @len: size of palette for a depth
300 * Gets the default colormap for a specific screen depth. @len
301 * is the size of the palette for a particular screen depth.
303 * Returns pointer to a frame buffer colormap structure.
307 const struct fb_cmap *fb_default_cmap(int len)
310 return &default_2_colors;
312 return &default_4_colors;
314 return &default_8_colors;
315 return &default_16_colors;
320 * fb_invert_cmaps - invert all defaults colormaps
322 * Invert all default colormaps.
326 void fb_invert_cmaps(void)
330 for (i = 0; i < ARRAY_SIZE(red2); i++) {
332 green2[i] = ~green2[i];
333 blue2[i] = ~blue2[i];
335 for (i = 0; i < ARRAY_SIZE(red4); i++) {
337 green4[i] = ~green4[i];
338 blue4[i] = ~blue4[i];
340 for (i = 0; i < ARRAY_SIZE(red8); i++) {
342 green8[i] = ~green8[i];
343 blue8[i] = ~blue8[i];
345 for (i = 0; i < ARRAY_SIZE(red16); i++) {
346 red16[i] = ~red16[i];
347 green16[i] = ~green16[i];
348 blue16[i] = ~blue16[i];
354 * Visible symbols for modules
357 EXPORT_SYMBOL(fb_alloc_cmap);
358 EXPORT_SYMBOL(fb_dealloc_cmap);
359 EXPORT_SYMBOL(fb_copy_cmap);
360 EXPORT_SYMBOL(fb_set_cmap);
361 EXPORT_SYMBOL(fb_default_cmap);
362 EXPORT_SYMBOL(fb_invert_cmaps);