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 int tooff = 0, fromoff = 0; 167 int size; 168 169 if (to->start > from->start) 170 fromoff = to->start - from->start; 171 else 172 tooff = from->start - to->start; 173 size = to->len - tooff; 174 if (size > (int) (from->len - fromoff)) 175 size = from->len - fromoff; 176 if (size <= 0) 177 return -EINVAL; 178 size *= sizeof(u16); 179 180 memcpy(to->red+tooff, from->red+fromoff, size); 181 memcpy(to->green+tooff, from->green+fromoff, size); 182 memcpy(to->blue+tooff, from->blue+fromoff, size); 183 if (from->transp && to->transp) 184 memcpy(to->transp+tooff, from->transp+fromoff, size); 185 return 0; 186 } 187 188 int fb_cmap_to_user(const struct fb_cmap *from, struct fb_cmap_user *to) 189 { 190 int tooff = 0, fromoff = 0; 191 int size; 192 193 if (to->start > from->start) 194 fromoff = to->start - from->start; 195 else 196 tooff = from->start - to->start; 197 size = to->len - tooff; 198 if (size > (int) (from->len - fromoff)) 199 size = from->len - fromoff; 200 if (size <= 0) 201 return -EINVAL; 202 size *= sizeof(u16); 203 204 if (copy_to_user(to->red+tooff, from->red+fromoff, size)) 205 return -EFAULT; 206 if (copy_to_user(to->green+tooff, from->green+fromoff, size)) 207 return -EFAULT; 208 if (copy_to_user(to->blue+tooff, from->blue+fromoff, size)) 209 return -EFAULT; 210 if (from->transp && to->transp) 211 if (copy_to_user(to->transp+tooff, from->transp+fromoff, size)) 212 return -EFAULT; 213 return 0; 214 } 215 216 /** 217 * fb_set_cmap - set the colormap 218 * @cmap: frame buffer colormap structure 219 * @info: frame buffer info structure 220 * 221 * Sets the colormap @cmap for a screen of device @info. 222 * 223 * Returns negative errno on error, or zero on success. 224 * 225 */ 226 227 int fb_set_cmap(struct fb_cmap *cmap, struct fb_info *info) 228 { 229 int i, start, rc = 0; 230 u16 *red, *green, *blue, *transp; 231 u_int hred, hgreen, hblue, htransp = 0xffff; 232 233 red = cmap->red; 234 green = cmap->green; 235 blue = cmap->blue; 236 transp = cmap->transp; 237 start = cmap->start; 238 239 if (start < 0 || (!info->fbops->fb_setcolreg && 240 !info->fbops->fb_setcmap)) 241 return -EINVAL; 242 if (info->fbops->fb_setcmap) { 243 rc = info->fbops->fb_setcmap(cmap, info); 244 } else { 245 for (i = 0; i < cmap->len; i++) { 246 hred = *red++; 247 hgreen = *green++; 248 hblue = *blue++; 249 if (transp) 250 htransp = *transp++; 251 if (info->fbops->fb_setcolreg(start++, 252 hred, hgreen, hblue, 253 htransp, info)) 254 break; 255 } 256 } 257 if (rc == 0) 258 fb_copy_cmap(cmap, &info->cmap); 259 260 return rc; 261 } 262 263 int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info) 264 { 265 int rc, size = cmap->len * sizeof(u16); 266 struct fb_cmap umap; 267 268 if (size < 0 || size < cmap->len) 269 return -E2BIG; 270 271 memset(&umap, 0, sizeof(struct fb_cmap)); 272 rc = fb_alloc_cmap_gfp(&umap, cmap->len, cmap->transp != NULL, 273 GFP_KERNEL); 274 if (rc) 275 return rc; 276 if (copy_from_user(umap.red, cmap->red, size) || 277 copy_from_user(umap.green, cmap->green, size) || 278 copy_from_user(umap.blue, cmap->blue, size) || 279 (cmap->transp && copy_from_user(umap.transp, cmap->transp, size))) { 280 rc = -EFAULT; 281 goto out; 282 } 283 umap.start = cmap->start; 284 if (!lock_fb_info(info)) { 285 rc = -ENODEV; 286 goto out; 287 } 288 289 rc = fb_set_cmap(&umap, info); 290 unlock_fb_info(info); 291 out: 292 fb_dealloc_cmap(&umap); 293 return rc; 294 } 295 296 /** 297 * fb_default_cmap - get default colormap 298 * @len: size of palette for a depth 299 * 300 * Gets the default colormap for a specific screen depth. @len 301 * is the size of the palette for a particular screen depth. 302 * 303 * Returns pointer to a frame buffer colormap structure. 304 * 305 */ 306 307 const 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 colormaps 321 * 322 * Invert all default colormaps. 323 * 324 */ 325 326 void 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 modules 355 */ 356 357 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); 363