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1/*2 * linux/drivers/video/fbcmap.c -- Colormap handling for frame buffer devices3 *4 * Created 15 Jun 1997 by Geert Uytterhoeven5 *6 * 2001 - Documented with DocBook7 * - Brad Douglas <brad@neruo.com>8 *9 * This file is subject to the terms and conditions of the GNU General Public10 * License. See the file COPYING in the main directory of this archive for11 * more details.12 */13 14#include <linux/string.h>15#include <linux/module.h>16#include <linux/fb.h>17#include <linux/slab.h>18#include <linux/uaccess.h>19 20static u16 red2[] __read_mostly = {21 0x0000, 0xaaaa22};23static u16 green2[] __read_mostly = {24 0x0000, 0xaaaa25};26static u16 blue2[] __read_mostly = {27 0x0000, 0xaaaa28};29 30static u16 red4[] __read_mostly = {31 0x0000, 0xaaaa, 0x5555, 0xffff32};33static u16 green4[] __read_mostly = {34 0x0000, 0xaaaa, 0x5555, 0xffff35};36static u16 blue4[] __read_mostly = {37 0x0000, 0xaaaa, 0x5555, 0xffff38};39 40static u16 red8[] __read_mostly = {41 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa42};43static u16 green8[] __read_mostly = {44 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa45};46static u16 blue8[] __read_mostly = {47 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa48};49 50static u16 red16[] __read_mostly = {51 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa,52 0x5555, 0x5555, 0x5555, 0x5555, 0xffff, 0xffff, 0xffff, 0xffff53};54static u16 green16[] __read_mostly = {55 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa,56 0x5555, 0x5555, 0xffff, 0xffff, 0x5555, 0x5555, 0xffff, 0xffff57};58static u16 blue16[] __read_mostly = {59 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa,60 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff61};62 63static const struct fb_cmap default_2_colors = {64 .len=2, .red=red2, .green=green2, .blue=blue265};66static const struct fb_cmap default_8_colors = {67 .len=8, .red=red8, .green=green8, .blue=blue868};69static const struct fb_cmap default_4_colors = {70 .len=4, .red=red4, .green=green4, .blue=blue471};72static const struct fb_cmap default_16_colors = {73 .len=16, .red=red16, .green=green16, .blue=blue1674};75 76 77 78/**79 * fb_alloc_cmap_gfp - allocate a colormap80 * @cmap: frame buffer colormap structure81 * @len: length of @cmap82 * @transp: boolean, 1 if there is transparency, 0 otherwise83 * @flags: flags for kmalloc memory allocation84 *85 * Allocates memory for a colormap @cmap. @len is the86 * number of entries in the palette.87 *88 * Returns negative errno on error, or zero on success.89 *90 */91 92int fb_alloc_cmap_gfp(struct fb_cmap *cmap, int len, int transp, gfp_t flags)93{94 int size = len * sizeof(u16);95 int ret = -ENOMEM;96 97 flags |= __GFP_NOWARN;98 99 if (cmap->len != len) {100 fb_dealloc_cmap(cmap);101 if (!len)102 return 0;103 104 cmap->red = kzalloc(size, flags);105 if (!cmap->red)106 goto fail;107 cmap->green = kzalloc(size, flags);108 if (!cmap->green)109 goto fail;110 cmap->blue = kzalloc(size, flags);111 if (!cmap->blue)112 goto fail;113 if (transp) {114 cmap->transp = kzalloc(size, flags);115 if (!cmap->transp)116 goto fail;117 } else {118 cmap->transp = NULL;119 }120 }121 cmap->start = 0;122 cmap->len = len;123 ret = fb_copy_cmap(fb_default_cmap(len), cmap);124 if (ret)125 goto fail;126 return 0;127 128fail:129 fb_dealloc_cmap(cmap);130 return ret;131}132 133int fb_alloc_cmap(struct fb_cmap *cmap, int len, int transp)134{135 return fb_alloc_cmap_gfp(cmap, len, transp, GFP_ATOMIC);136}137 138/**139 * fb_dealloc_cmap - deallocate a colormap140 * @cmap: frame buffer colormap structure141 *142 * Deallocates a colormap that was previously allocated with143 * fb_alloc_cmap().144 *145 */146 147void fb_dealloc_cmap(struct fb_cmap *cmap)148{149 kfree(cmap->red);150 kfree(cmap->green);151 kfree(cmap->blue);152 kfree(cmap->transp);153 154 cmap->red = cmap->green = cmap->blue = cmap->transp = NULL;155 cmap->len = 0;156}157 158/**159 * fb_copy_cmap - copy a colormap160 * @from: frame buffer colormap structure161 * @to: frame buffer colormap structure162 *163 * Copy contents of colormap from @from to @to.164 */165 166int fb_copy_cmap(const struct fb_cmap *from, struct fb_cmap *to)167{168 unsigned int tooff = 0, fromoff = 0;169 size_t size;170 171 if (to->start > from->start)172 fromoff = to->start - from->start;173 else174 tooff = from->start - to->start;175 if (fromoff >= from->len || tooff >= to->len)176 return -EINVAL;177 178 size = min_t(size_t, to->len - tooff, from->len - fromoff);179 if (size == 0)180 return -EINVAL;181 size *= sizeof(u16);182 183 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);188 return 0;189}190 191int fb_cmap_to_user(const struct fb_cmap *from, struct fb_cmap_user *to)192{193 unsigned int tooff = 0, fromoff = 0;194 size_t size;195 196 if (to->start > from->start)197 fromoff = to->start - from->start;198 else199 tooff = from->start - to->start;200 if (fromoff >= from->len || tooff >= to->len)201 return -EINVAL;202 203 size = min_t(size_t, to->len - tooff, from->len - fromoff);204 if (size == 0)205 return -EINVAL;206 size *= sizeof(u16);207 208 if (copy_to_user(to->red+tooff, from->red+fromoff, size))209 return -EFAULT;210 if (copy_to_user(to->green+tooff, from->green+fromoff, size))211 return -EFAULT;212 if (copy_to_user(to->blue+tooff, from->blue+fromoff, size))213 return -EFAULT;214 if (from->transp && to->transp)215 if (copy_to_user(to->transp+tooff, from->transp+fromoff, size))216 return -EFAULT;217 return 0;218}219 220/**221 * fb_set_cmap - set the colormap222 * @cmap: frame buffer colormap structure223 * @info: frame buffer info structure224 *225 * Sets the colormap @cmap for a screen of device @info.226 *227 * Returns negative errno on error, or zero on success.228 *229 */230 231int fb_set_cmap(struct fb_cmap *cmap, struct fb_info *info)232{233 int i, start, rc = 0;234 u16 *red, *green, *blue, *transp;235 u_int hred, hgreen, hblue, htransp = 0xffff;236 237 red = cmap->red;238 green = cmap->green;239 blue = cmap->blue;240 transp = cmap->transp;241 start = cmap->start;242 243 if (start < 0 || (!info->fbops->fb_setcolreg &&244 !info->fbops->fb_setcmap))245 return -EINVAL;246 if (info->fbops->fb_setcmap) {247 rc = info->fbops->fb_setcmap(cmap, info);248 } else {249 for (i = 0; i < cmap->len; i++) {250 hred = *red++;251 hgreen = *green++;252 hblue = *blue++;253 if (transp)254 htransp = *transp++;255 if (info->fbops->fb_setcolreg(start++,256 hred, hgreen, hblue,257 htransp, info))258 break;259 }260 }261 if (rc == 0)262 fb_copy_cmap(cmap, &info->cmap);263 264 return rc;265}266 267int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info)268{269 int rc, size = cmap->len * sizeof(u16);270 struct fb_cmap umap;271 272 if (size < 0 || size < cmap->len)273 return -E2BIG;274 275 memset(&umap, 0, sizeof(struct fb_cmap));276 rc = fb_alloc_cmap_gfp(&umap, cmap->len, cmap->transp != NULL,277 GFP_KERNEL);278 if (rc)279 return rc;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))) {284 rc = -EFAULT;285 goto out;286 }287 umap.start = cmap->start;288 lock_fb_info(info);289 rc = fb_set_cmap(&umap, info);290 unlock_fb_info(info);291out:292 fb_dealloc_cmap(&umap);293 return rc;294}295 296/**297 * fb_default_cmap - get default colormap298 * @len: size of palette for a depth299 *300 * Gets the default colormap for a specific screen depth. @len301 * is the size of the palette for a particular screen depth.302 *303 * Returns pointer to a frame buffer colormap structure.304 *305 */306 307const struct fb_cmap *fb_default_cmap(int len)308{309 if (len <= 2)310 return &default_2_colors;311 if (len <= 4)312 return &default_4_colors;313 if (len <= 8)314 return &default_8_colors;315 return &default_16_colors;316}317 318 319/**320 * fb_invert_cmaps - invert all defaults colormaps321 *322 * Invert all default colormaps.323 *324 */325 326void fb_invert_cmaps(void)327{328 u_int i;329 330 for (i = 0; i < ARRAY_SIZE(red2); i++) {331 red2[i] = ~red2[i];332 green2[i] = ~green2[i];333 blue2[i] = ~blue2[i];334 }335 for (i = 0; i < ARRAY_SIZE(red4); i++) {336 red4[i] = ~red4[i];337 green4[i] = ~green4[i];338 blue4[i] = ~blue4[i];339 }340 for (i = 0; i < ARRAY_SIZE(red8); i++) {341 red8[i] = ~red8[i];342 green8[i] = ~green8[i];343 blue8[i] = ~blue8[i];344 }345 for (i = 0; i < ARRAY_SIZE(red16); i++) {346 red16[i] = ~red16[i];347 green16[i] = ~green16[i];348 blue16[i] = ~blue16[i];349 }350}351 352 353 /*354 * Visible symbols for modules355 */356 357EXPORT_SYMBOL(fb_alloc_cmap);358EXPORT_SYMBOL(fb_dealloc_cmap);359EXPORT_SYMBOL(fb_copy_cmap);360EXPORT_SYMBOL(fb_set_cmap);361EXPORT_SYMBOL(fb_default_cmap);362EXPORT_SYMBOL(fb_invert_cmaps);363