1/* 2 * linux/drivers/video/fbcmap.c -- Colormap handling for frame buffer devices 3 * 4 * Created 15 Jun 1997 by Geert Uytterhoeven 5 * 6 * 2001 - Documented with DocBook 7 * - Brad Douglas <brad@neruo.com> 8 * 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 11 * 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, 0xaaaa 22}; 23static u16 green2[] __read_mostly = { 24 0x0000, 0xaaaa 25}; 26static u16 blue2[] __read_mostly = { 27 0x0000, 0xaaaa 28}; 29 30static u16 red4[] __read_mostly = { 31 0x0000, 0xaaaa, 0x5555, 0xffff 32}; 33static u16 green4[] __read_mostly = { 34 0x0000, 0xaaaa, 0x5555, 0xffff 35}; 36static u16 blue4[] __read_mostly = { 37 0x0000, 0xaaaa, 0x5555, 0xffff 38}; 39 40static u16 red8[] __read_mostly = { 41 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa 42}; 43static u16 green8[] __read_mostly = { 44 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa 45}; 46static u16 blue8[] __read_mostly = { 47 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa 48}; 49 50static u16 red16[] __read_mostly = { 51 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa, 52 0x5555, 0x5555, 0x5555, 0x5555, 0xffff, 0xffff, 0xffff, 0xffff 53}; 54static u16 green16[] __read_mostly = { 55 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa, 56 0x5555, 0x5555, 0xffff, 0xffff, 0x5555, 0x5555, 0xffff, 0xffff 57}; 58static u16 blue16[] __read_mostly = { 59 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 60 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff 61}; 62 63static const struct fb_cmap default_2_colors = { 64 .len=2, .red=red2, .green=green2, .blue=blue2 65}; 66static const struct fb_cmap default_8_colors = { 67 .len=8, .red=red8, .green=green8, .blue=blue8 68}; 69static const struct fb_cmap default_4_colors = { 70 .len=4, .red=red4, .green=green4, .blue=blue4 71}; 72static const struct fb_cmap default_16_colors = { 73 .len=16, .red=red16, .green=green16, .blue=blue16 74}; 75 76 77 78/** 79 * fb_alloc_cmap - 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 * 84 * Allocates memory for a colormap @cmap. @len is the 85 * number of entries in the palette. 86 * 87 * Returns negative errno on error, or zero on success. 88 * 89 */ 90 91int fb_alloc_cmap(struct fb_cmap *cmap, int len, int transp) 92{ 93 int size = len*sizeof(u16); 94 95 if (cmap->len != len) { 96 fb_dealloc_cmap(cmap); 97 if (!len) 98 return 0; 99 if (!(cmap->red = kmalloc(size, GFP_ATOMIC))) 100 goto fail; 101 if (!(cmap->green = kmalloc(size, GFP_ATOMIC))) 102 goto fail; 103 if (!(cmap->blue = kmalloc(size, GFP_ATOMIC))) 104 goto fail; 105 if (transp) { 106 if (!(cmap->transp = kmalloc(size, GFP_ATOMIC))) 107 goto fail; 108 } else 109 cmap->transp = NULL; 110 } 111 cmap->start = 0; 112 cmap->len = len; 113 fb_copy_cmap(fb_default_cmap(len), cmap); 114 return 0; 115 116fail: 117 fb_dealloc_cmap(cmap); 118 return -ENOMEM; 119} 120 121/** 122 * fb_dealloc_cmap - deallocate a colormap 123 * @cmap: frame buffer colormap structure 124 * 125 * Deallocates a colormap that was previously allocated with 126 * fb_alloc_cmap(). 127 * 128 */ 129 130void fb_dealloc_cmap(struct fb_cmap *cmap) 131{ 132 kfree(cmap->red); 133 kfree(cmap->green); 134 kfree(cmap->blue); 135 kfree(cmap->transp); 136 137 cmap->red = cmap->green = cmap->blue = cmap->transp = NULL; 138 cmap->len = 0; 139} 140 141/** 142 * fb_copy_cmap - copy a colormap 143 * @from: frame buffer colormap structure 144 * @to: frame buffer colormap structure 145 * 146 * Copy contents of colormap from @from to @to. 147 */ 148 149int fb_copy_cmap(const struct fb_cmap *from, struct fb_cmap *to) 150{ 151 int tooff = 0, fromoff = 0; 152 int size; 153 154 if (to->start > from->start) 155 fromoff = to->start - from->start; 156 else 157 tooff = from->start - to->start; 158 size = to->len - tooff; 159 if (size > (int) (from->len - fromoff)) 160 size = from->len - fromoff; 161 if (size <= 0) 162 return -EINVAL; 163 size *= sizeof(u16); 164 165 memcpy(to->red+tooff, from->red+fromoff, size); 166 memcpy(to->green+tooff, from->green+fromoff, size); 167 memcpy(to->blue+tooff, from->blue+fromoff, size); 168 if (from->transp && to->transp) 169 memcpy(to->transp+tooff, from->transp+fromoff, size); 170 return 0; 171} 172 173int fb_cmap_to_user(const struct fb_cmap *from, struct fb_cmap_user *to) 174{ 175 int tooff = 0, fromoff = 0; 176 int size; 177 178 if (to->start > from->start) 179 fromoff = to->start - from->start; 180 else 181 tooff = from->start - to->start; 182 size = to->len - tooff; 183 if (size > (int) (from->len - fromoff)) 184 size = from->len - fromoff; 185 if (size <= 0) 186 return -EINVAL; 187 size *= sizeof(u16); 188 189 if (copy_to_user(to->red+tooff, from->red+fromoff, size)) 190 return -EFAULT; 191 if (copy_to_user(to->green+tooff, from->green+fromoff, size)) 192 return -EFAULT; 193 if (copy_to_user(to->blue+tooff, from->blue+fromoff, size)) 194 return -EFAULT; 195 if (from->transp && to->transp) 196 if (copy_to_user(to->transp+tooff, from->transp+fromoff, size)) 197 return -EFAULT; 198 return 0; 199} 200 201/** 202 * fb_set_cmap - set the colormap 203 * @cmap: frame buffer colormap structure 204 * @info: frame buffer info structure 205 * 206 * Sets the colormap @cmap for a screen of device @info. 207 * 208 * Returns negative errno on error, or zero on success. 209 * 210 */ 211 212int fb_set_cmap(struct fb_cmap *cmap, struct fb_info *info) 213{ 214 int i, start, rc = 0; 215 u16 *red, *green, *blue, *transp; 216 u_int hred, hgreen, hblue, htransp = 0xffff; 217 218 red = cmap->red; 219 green = cmap->green; 220 blue = cmap->blue; 221 transp = cmap->transp; 222 start = cmap->start; 223 224 if (start < 0 || (!info->fbops->fb_setcolreg && 225 !info->fbops->fb_setcmap)) 226 return -EINVAL; 227 if (info->fbops->fb_setcmap) { 228 rc = info->fbops->fb_setcmap(cmap, info); 229 } else { 230 for (i = 0; i < cmap->len; i++) { 231 hred = *red++; 232 hgreen = *green++; 233 hblue = *blue++; 234 if (transp) 235 htransp = *transp++; 236 if (info->fbops->fb_setcolreg(start++, 237 hred, hgreen, hblue, 238 htransp, info)) 239 break; 240 } 241 } 242 if (rc == 0) 243 fb_copy_cmap(cmap, &info->cmap); 244 245 return rc; 246} 247 248int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info) 249{ 250 int rc, size = cmap->len * sizeof(u16); 251 struct fb_cmap umap; 252 253 memset(&umap, 0, sizeof(struct fb_cmap)); 254 rc = fb_alloc_cmap(&umap, cmap->len, cmap->transp != NULL); 255 if (rc) 256 return rc; 257 if (copy_from_user(umap.red, cmap->red, size) || 258 copy_from_user(umap.green, cmap->green, size) || 259 copy_from_user(umap.blue, cmap->blue, size) || 260 (cmap->transp && copy_from_user(umap.transp, cmap->transp, size))) { 261 rc = -EFAULT; 262 goto out; 263 } 264 umap.start = cmap->start; 265 if (!lock_fb_info(info)) { 266 rc = -ENODEV; 267 goto out; 268 } 269 if (cmap->start < 0 || (!info->fbops->fb_setcolreg && 270 !info->fbops->fb_setcmap)) { 271 rc = -EINVAL; 272 goto out1; 273 } 274 rc = fb_set_cmap(&umap, info); 275out1: 276 unlock_fb_info(info); 277out: 278 fb_dealloc_cmap(&umap); 279 return rc; 280} 281 282/** 283 * fb_default_cmap - get default colormap 284 * @len: size of palette for a depth 285 * 286 * Gets the default colormap for a specific screen depth. @len 287 * is the size of the palette for a particular screen depth. 288 * 289 * Returns pointer to a frame buffer colormap structure. 290 * 291 */ 292 293const struct fb_cmap *fb_default_cmap(int len) 294{ 295 if (len <= 2) 296 return &default_2_colors; 297 if (len <= 4) 298 return &default_4_colors; 299 if (len <= 8) 300 return &default_8_colors; 301 return &default_16_colors; 302} 303 304 305/** 306 * fb_invert_cmaps - invert all defaults colormaps 307 * 308 * Invert all default colormaps. 309 * 310 */ 311 312void fb_invert_cmaps(void) 313{ 314 u_int i; 315 316 for (i = 0; i < ARRAY_SIZE(red2); i++) { 317 red2[i] = ~red2[i]; 318 green2[i] = ~green2[i]; 319 blue2[i] = ~blue2[i]; 320 } 321 for (i = 0; i < ARRAY_SIZE(red4); i++) { 322 red4[i] = ~red4[i]; 323 green4[i] = ~green4[i]; 324 blue4[i] = ~blue4[i]; 325 } 326 for (i = 0; i < ARRAY_SIZE(red8); i++) { 327 red8[i] = ~red8[i]; 328 green8[i] = ~green8[i]; 329 blue8[i] = ~blue8[i]; 330 } 331 for (i = 0; i < ARRAY_SIZE(red16); i++) { 332 red16[i] = ~red16[i]; 333 green16[i] = ~green16[i]; 334 blue16[i] = ~blue16[i]; 335 } 336} 337 338 339 /* 340 * Visible symbols for modules 341 */ 342 343EXPORT_SYMBOL(fb_alloc_cmap); 344EXPORT_SYMBOL(fb_dealloc_cmap); 345EXPORT_SYMBOL(fb_copy_cmap); 346EXPORT_SYMBOL(fb_set_cmap); 347EXPORT_SYMBOL(fb_default_cmap); 348EXPORT_SYMBOL(fb_invert_cmaps); 349