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_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 |
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 | 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(from: fb_default_cmap(len), to: cmap); |
124 | if (ret) |
125 | goto fail; |
126 | return 0; |
127 | |
128 | fail: |
129 | fb_dealloc_cmap(cmap); |
130 | return ret; |
131 | } |
132 | |
133 | int 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 colormap |
140 | * @cmap: frame buffer colormap structure |
141 | * |
142 | * Deallocates a colormap that was previously allocated with |
143 | * fb_alloc_cmap(). |
144 | * |
145 | */ |
146 | |
147 | void fb_dealloc_cmap(struct fb_cmap *cmap) |
148 | { |
149 | kfree(objp: cmap->red); |
150 | kfree(objp: cmap->green); |
151 | kfree(objp: cmap->blue); |
152 | kfree(objp: 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 colormap |
160 | * @from: frame buffer colormap structure |
161 | * @to: frame buffer colormap structure |
162 | * |
163 | * Copy contents of colormap from @from to @to. |
164 | */ |
165 | |
166 | int 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 | else |
174 | 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 | |
191 | int 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 | else |
199 | 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: to->red+tooff, from: from->red+fromoff, n: size)) |
209 | return -EFAULT; |
210 | if (copy_to_user(to: to->green+tooff, from: from->green+fromoff, n: size)) |
211 | return -EFAULT; |
212 | if (copy_to_user(to: to->blue+tooff, from: from->blue+fromoff, n: size)) |
213 | return -EFAULT; |
214 | if (from->transp && to->transp) |
215 | if (copy_to_user(to: to->transp+tooff, from: from->transp+fromoff, n: size)) |
216 | return -EFAULT; |
217 | return 0; |
218 | } |
219 | |
220 | /** |
221 | * fb_set_cmap - set the colormap |
222 | * @cmap: frame buffer colormap structure |
223 | * @info: frame buffer info structure |
224 | * |
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 | |
231 | int 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(from: cmap, to: &info->cmap); |
263 | |
264 | return rc; |
265 | } |
266 | |
267 | int 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(cmap: &umap, len: cmap->len, transp: cmap->transp != NULL, |
277 | GFP_KERNEL); |
278 | if (rc) |
279 | return rc; |
280 | if (copy_from_user(to: umap.red, from: cmap->red, n: size) || |
281 | copy_from_user(to: umap.green, from: cmap->green, n: size) || |
282 | copy_from_user(to: umap.blue, from: cmap->blue, n: size) || |
283 | (cmap->transp && copy_from_user(to: umap.transp, from: cmap->transp, n: size))) { |
284 | rc = -EFAULT; |
285 | goto out; |
286 | } |
287 | umap.start = cmap->start; |
288 | lock_fb_info(info); |
289 | rc = fb_set_cmap(cmap: &umap, info); |
290 | unlock_fb_info(info); |
291 | out: |
292 | fb_dealloc_cmap(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 | |