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 20 static u16 red2[] __read_mostly = { 21 0x0000, 0xaaaa 22 }; 23 static u16 green2[] __read_mostly = { 24 0x0000, 0xaaaa 25 }; 26 static u16 blue2[] __read_mostly = { 27 0x0000, 0xaaaa 28 }; 29 30 static u16 red4[] __read_mostly = { 31 0x0000, 0xaaaa, 0x5555, 0xffff 32 }; 33 static u16 green4[] __read_mostly = { 34 0x0000, 0xaaaa, 0x5555, 0xffff 35 }; 36 static u16 blue4[] __read_mostly = { 37 0x0000, 0xaaaa, 0x5555, 0xffff 38 }; 39 40 static u16 red8[] __read_mostly = { 41 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa 42 }; 43 static u16 green8[] __read_mostly = { 44 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa 45 }; 46 static u16 blue8[] __read_mostly = { 47 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa 48 }; 49 50 static u16 red16[] __read_mostly = { 51 0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa, 52 0x5555, 0x5555, 0x5555, 0x5555, 0xffff, 0xffff, 0xffff, 0xffff 53 }; 54 static u16 green16[] __read_mostly = { 55 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa, 56 0x5555, 0x5555, 0xffff, 0xffff, 0x5555, 0x5555, 0xffff, 0xffff 57 }; 58 static u16 blue16[] __read_mostly = { 59 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 60 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff 61 }; 62 63 static const struct fb_cmap default_2_colors = { 64 .len=2, .red=red2, .green=green2, .blue=blue2 65 }; 66 static const struct fb_cmap default_8_colors = { 67 .len=8, .red=red8, .green=green8, .blue=blue8 68 }; 69 static const struct fb_cmap default_4_colors = { 70 .len=4, .red=red4, .green=green4, .blue=blue4 71 }; 72 static 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 * @flags: flags for kmalloc memory allocation 84 * 85 * Allocates memory for a colormap @cmap. @len is the 86 * number of entries in the palette. 87 * 88 * Returns negative errno on error, or zero on success. 89 * 90 */ 91 92 int 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 if (cmap->len != len) { 98 fb_dealloc_cmap(cmap); 99 if (!len) 100 return 0; 101 102 cmap->red = kmalloc(size, flags); 103 if (!cmap->red) 104 goto fail; 105 cmap->green = kmalloc(size, flags); 106 if (!cmap->green) 107 goto fail; 108 cmap->blue = kmalloc(size, flags); 109 if (!cmap->blue) 110 goto fail; 111 if (transp) { 112 cmap->transp = kmalloc(size, flags); 113 if (!cmap->transp) 114 goto fail; 115 } else { 116 cmap->transp = NULL; 117 } 118 } 119 cmap->start = 0; 120 cmap->len = len; 121 ret = fb_copy_cmap(fb_default_cmap(len), cmap); 122 if (ret) 123 goto fail; 124 return 0; 125 126 fail: 127 fb_dealloc_cmap(cmap); 128 return ret; 129 } 130 131 int fb_alloc_cmap(struct fb_cmap *cmap, int len, int transp) 132 { 133 return fb_alloc_cmap_gfp(cmap, len, transp, GFP_ATOMIC); 134 } 135 136 /** 137 * fb_dealloc_cmap - deallocate a colormap 138 * @cmap: frame buffer colormap structure 139 * 140 * Deallocates a colormap that was previously allocated with 141 * fb_alloc_cmap(). 142 * 143 */ 144 145 void fb_dealloc_cmap(struct fb_cmap *cmap) 146 { 147 kfree(cmap->red); 148 kfree(cmap->green); 149 kfree(cmap->blue); 150 kfree(cmap->transp); 151 152 cmap->red = cmap->green = cmap->blue = cmap->transp = NULL; 153 cmap->len = 0; 154 } 155 156 /** 157 * fb_copy_cmap - copy a colormap 158 * @from: frame buffer colormap structure 159 * @to: frame buffer colormap structure 160 * 161 * Copy contents of colormap from @from to @to. 162 */ 163 164 int fb_copy_cmap(const struct fb_cmap *from, struct fb_cmap *to) 165 { 166 unsigned int tooff = 0, fromoff = 0; 167 size_t size; 168 169 if (to->start > from->start) 170 fromoff = to->start - from->start; 171 else 172 tooff = from->start - to->start; 173 if (fromoff >= from->len || tooff >= to->len) 174 return -EINVAL; 175 176 size = min_t(size_t, to->len - tooff, from->len - fromoff); 177 if (size == 0) 178 return -EINVAL; 179 size *= sizeof(u16); 180 181 memcpy(to->red+tooff, from->red+fromoff, size); 182 memcpy(to->green+tooff, from->green+fromoff, size); 183 memcpy(to->blue+tooff, from->blue+fromoff, size); 184 if (from->transp && to->transp) 185 memcpy(to->transp+tooff, from->transp+fromoff, size); 186 return 0; 187 } 188 189 int fb_cmap_to_user(const struct fb_cmap *from, struct fb_cmap_user *to) 190 { 191 unsigned int tooff = 0, fromoff = 0; 192 size_t size; 193 194 if (to->start > from->start) 195 fromoff = to->start - from->start; 196 else 197 tooff = from->start - to->start; 198 if (fromoff >= from->len || tooff >= to->len) 199 return -EINVAL; 200 201 size = min_t(size_t, to->len - tooff, from->len - fromoff); 202 if (size == 0) 203 return -EINVAL; 204 size *= sizeof(u16); 205 206 if (copy_to_user(to->red+tooff, from->red+fromoff, size)) 207 return -EFAULT; 208 if (copy_to_user(to->green+tooff, from->green+fromoff, size)) 209 return -EFAULT; 210 if (copy_to_user(to->blue+tooff, from->blue+fromoff, size)) 211 return -EFAULT; 212 if (from->transp && to->transp) 213 if (copy_to_user(to->transp+tooff, from->transp+fromoff, size)) 214 return -EFAULT; 215 return 0; 216 } 217 218 /** 219 * fb_set_cmap - set the colormap 220 * @cmap: frame buffer colormap structure 221 * @info: frame buffer info structure 222 * 223 * Sets the colormap @cmap for a screen of device @info. 224 * 225 * Returns negative errno on error, or zero on success. 226 * 227 */ 228 229 int fb_set_cmap(struct fb_cmap *cmap, struct fb_info *info) 230 { 231 int i, start, rc = 0; 232 u16 *red, *green, *blue, *transp; 233 u_int hred, hgreen, hblue, htransp = 0xffff; 234 235 red = cmap->red; 236 green = cmap->green; 237 blue = cmap->blue; 238 transp = cmap->transp; 239 start = cmap->start; 240 241 if (start < 0 || (!info->fbops->fb_setcolreg && 242 !info->fbops->fb_setcmap)) 243 return -EINVAL; 244 if (info->fbops->fb_setcmap) { 245 rc = info->fbops->fb_setcmap(cmap, info); 246 } else { 247 for (i = 0; i < cmap->len; i++) { 248 hred = *red++; 249 hgreen = *green++; 250 hblue = *blue++; 251 if (transp) 252 htransp = *transp++; 253 if (info->fbops->fb_setcolreg(start++, 254 hred, hgreen, hblue, 255 htransp, info)) 256 break; 257 } 258 } 259 if (rc == 0) 260 fb_copy_cmap(cmap, &info->cmap); 261 262 return rc; 263 } 264 265 int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info) 266 { 267 int rc, size = cmap->len * sizeof(u16); 268 struct fb_cmap umap; 269 270 if (size < 0 || size < cmap->len) 271 return -E2BIG; 272 273 memset(&umap, 0, sizeof(struct fb_cmap)); 274 rc = fb_alloc_cmap_gfp(&umap, cmap->len, cmap->transp != NULL, 275 GFP_KERNEL); 276 if (rc) 277 return rc; 278 if (copy_from_user(umap.red, cmap->red, size) || 279 copy_from_user(umap.green, cmap->green, size) || 280 copy_from_user(umap.blue, cmap->blue, size) || 281 (cmap->transp && copy_from_user(umap.transp, cmap->transp, size))) { 282 rc = -EFAULT; 283 goto out; 284 } 285 umap.start = cmap->start; 286 if (!lock_fb_info(info)) { 287 rc = -ENODEV; 288 goto out; 289 } 290 291 rc = fb_set_cmap(&umap, info); 292 unlock_fb_info(info); 293 out: 294 fb_dealloc_cmap(&umap); 295 return rc; 296 } 297 298 /** 299 * fb_default_cmap - get default colormap 300 * @len: size of palette for a depth 301 * 302 * Gets the default colormap for a specific screen depth. @len 303 * is the size of the palette for a particular screen depth. 304 * 305 * Returns pointer to a frame buffer colormap structure. 306 * 307 */ 308 309 const struct fb_cmap *fb_default_cmap(int len) 310 { 311 if (len <= 2) 312 return &default_2_colors; 313 if (len <= 4) 314 return &default_4_colors; 315 if (len <= 8) 316 return &default_8_colors; 317 return &default_16_colors; 318 } 319 320 321 /** 322 * fb_invert_cmaps - invert all defaults colormaps 323 * 324 * Invert all default colormaps. 325 * 326 */ 327 328 void fb_invert_cmaps(void) 329 { 330 u_int i; 331 332 for (i = 0; i < ARRAY_SIZE(red2); i++) { 333 red2[i] = ~red2[i]; 334 green2[i] = ~green2[i]; 335 blue2[i] = ~blue2[i]; 336 } 337 for (i = 0; i < ARRAY_SIZE(red4); i++) { 338 red4[i] = ~red4[i]; 339 green4[i] = ~green4[i]; 340 blue4[i] = ~blue4[i]; 341 } 342 for (i = 0; i < ARRAY_SIZE(red8); i++) { 343 red8[i] = ~red8[i]; 344 green8[i] = ~green8[i]; 345 blue8[i] = ~blue8[i]; 346 } 347 for (i = 0; i < ARRAY_SIZE(red16); i++) { 348 red16[i] = ~red16[i]; 349 green16[i] = ~green16[i]; 350 blue16[i] = ~blue16[i]; 351 } 352 } 353 354 355 /* 356 * Visible symbols for modules 357 */ 358 359 EXPORT_SYMBOL(fb_alloc_cmap); 360 EXPORT_SYMBOL(fb_dealloc_cmap); 361 EXPORT_SYMBOL(fb_copy_cmap); 362 EXPORT_SYMBOL(fb_set_cmap); 363 EXPORT_SYMBOL(fb_default_cmap); 364 EXPORT_SYMBOL(fb_invert_cmaps); 365