[SCSI] advansys: Shrink advansys_board_found a little more
[linux-2.6] / drivers / video / fbcmap.c
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
19 #include <asm/uaccess.h>
20
21 static u16 red2[] __read_mostly = {
22     0x0000, 0xaaaa
23 };
24 static u16 green2[] __read_mostly = {
25     0x0000, 0xaaaa
26 };
27 static u16 blue2[] __read_mostly = {
28     0x0000, 0xaaaa
29 };
30
31 static u16 red4[] __read_mostly = {
32     0x0000, 0xaaaa, 0x5555, 0xffff
33 };
34 static u16 green4[] __read_mostly = {
35     0x0000, 0xaaaa, 0x5555, 0xffff
36 };
37 static u16 blue4[] __read_mostly = {
38     0x0000, 0xaaaa, 0x5555, 0xffff
39 };
40
41 static u16 red8[] __read_mostly = {
42     0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa
43 };
44 static u16 green8[] __read_mostly = {
45     0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa
46 };
47 static u16 blue8[] __read_mostly = {
48     0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa
49 };
50
51 static u16 red16[] __read_mostly = {
52     0x0000, 0x0000, 0x0000, 0x0000, 0xaaaa, 0xaaaa, 0xaaaa, 0xaaaa,
53     0x5555, 0x5555, 0x5555, 0x5555, 0xffff, 0xffff, 0xffff, 0xffff
54 };
55 static u16 green16[] __read_mostly = {
56     0x0000, 0x0000, 0xaaaa, 0xaaaa, 0x0000, 0x0000, 0x5555, 0xaaaa,
57     0x5555, 0x5555, 0xffff, 0xffff, 0x5555, 0x5555, 0xffff, 0xffff
58 };
59 static u16 blue16[] __read_mostly = {
60     0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa, 0x0000, 0xaaaa,
61     0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff, 0x5555, 0xffff
62 };
63
64 static const struct fb_cmap default_2_colors = {
65     .len=2, .red=red2, .green=green2, .blue=blue2
66 };
67 static const struct fb_cmap default_8_colors = {
68     .len=8, .red=red8, .green=green8, .blue=blue8
69 };
70 static const struct fb_cmap default_4_colors = {
71     .len=4, .red=red4, .green=green4, .blue=blue4
72 };
73 static const struct fb_cmap default_16_colors = {
74     .len=16, .red=red16, .green=green16, .blue=blue16
75 };
76
77
78
79 /**
80  *      fb_alloc_cmap - allocate a colormap
81  *      @cmap: frame buffer colormap structure
82  *      @len: length of @cmap
83  *      @transp: boolean, 1 if there is transparency, 0 otherwise
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(struct fb_cmap *cmap, int len, int transp)
93 {
94     int size = len*sizeof(u16);
95
96     if (cmap->len != len) {
97         fb_dealloc_cmap(cmap);
98         if (!len)
99             return 0;
100         if (!(cmap->red = kmalloc(size, GFP_ATOMIC)))
101             goto fail;
102         if (!(cmap->green = kmalloc(size, GFP_ATOMIC)))
103             goto fail;
104         if (!(cmap->blue = kmalloc(size, GFP_ATOMIC)))
105             goto fail;
106         if (transp) {
107             if (!(cmap->transp = kmalloc(size, GFP_ATOMIC)))
108                 goto fail;
109         } else
110             cmap->transp = NULL;
111     }
112     cmap->start = 0;
113     cmap->len = len;
114     fb_copy_cmap(fb_default_cmap(len), cmap);
115     return 0;
116
117 fail:
118     fb_dealloc_cmap(cmap);
119     return -ENOMEM;
120 }
121
122 /**
123  *      fb_dealloc_cmap - deallocate a colormap
124  *      @cmap: frame buffer colormap structure
125  *
126  *      Deallocates a colormap that was previously allocated with
127  *      fb_alloc_cmap().
128  *
129  */
130
131 void fb_dealloc_cmap(struct fb_cmap *cmap)
132 {
133         kfree(cmap->red);
134         kfree(cmap->green);
135         kfree(cmap->blue);
136         kfree(cmap->transp);
137
138         cmap->red = cmap->green = cmap->blue = cmap->transp = NULL;
139         cmap->len = 0;
140 }
141
142 /**
143  *      fb_copy_cmap - copy a colormap
144  *      @from: frame buffer colormap structure
145  *      @to: frame buffer colormap structure
146  *
147  *      Copy contents of colormap from @from to @to.
148  */
149
150 int fb_copy_cmap(const struct fb_cmap *from, struct fb_cmap *to)
151 {
152         int tooff = 0, fromoff = 0;
153         int size;
154
155         if (to->start > from->start)
156                 fromoff = to->start - from->start;
157         else
158                 tooff = from->start - to->start;
159         size = to->len - tooff;
160         if (size > (int) (from->len - fromoff))
161                 size = from->len - fromoff;
162         if (size <= 0)
163                 return -EINVAL;
164         size *= sizeof(u16);
165
166         memcpy(to->red+tooff, from->red+fromoff, size);
167         memcpy(to->green+tooff, from->green+fromoff, size);
168         memcpy(to->blue+tooff, from->blue+fromoff, size);
169         if (from->transp && to->transp)
170                 memcpy(to->transp+tooff, from->transp+fromoff, size);
171         return 0;
172 }
173
174 int fb_cmap_to_user(const struct fb_cmap *from, struct fb_cmap_user *to)
175 {
176         int tooff = 0, fromoff = 0;
177         int size;
178
179         if (to->start > from->start)
180                 fromoff = to->start - from->start;
181         else
182                 tooff = from->start - to->start;
183         size = to->len - tooff;
184         if (size > (int) (from->len - fromoff))
185                 size = from->len - fromoff;
186         if (size <= 0)
187                 return -EINVAL;
188         size *= sizeof(u16);
189
190         if (copy_to_user(to->red+tooff, from->red+fromoff, size))
191                 return -EFAULT;
192         if (copy_to_user(to->green+tooff, from->green+fromoff, size))
193                 return -EFAULT;
194         if (copy_to_user(to->blue+tooff, from->blue+fromoff, size))
195                 return -EFAULT;
196         if (from->transp && to->transp)
197                 if (copy_to_user(to->transp+tooff, from->transp+fromoff, size))
198                         return -EFAULT;
199         return 0;
200 }
201
202 /**
203  *      fb_set_cmap - set the colormap
204  *      @cmap: frame buffer colormap structure
205  *      @info: frame buffer info structure
206  *
207  *      Sets the colormap @cmap for a screen of device @info.
208  *
209  *      Returns negative errno on error, or zero on success.
210  *
211  */
212
213 int fb_set_cmap(struct fb_cmap *cmap, struct fb_info *info)
214 {
215         int i, start, rc = 0;
216         u16 *red, *green, *blue, *transp;
217         u_int hred, hgreen, hblue, htransp = 0xffff;
218
219         red = cmap->red;
220         green = cmap->green;
221         blue = cmap->blue;
222         transp = cmap->transp;
223         start = cmap->start;
224
225         if (start < 0 || (!info->fbops->fb_setcolreg &&
226                           !info->fbops->fb_setcmap))
227                 return -EINVAL;
228         if (info->fbops->fb_setcmap) {
229                 rc = info->fbops->fb_setcmap(cmap, info);
230         } else {
231                 for (i = 0; i < cmap->len; i++) {
232                         hred = *red++;
233                         hgreen = *green++;
234                         hblue = *blue++;
235                         if (transp)
236                                 htransp = *transp++;
237                         if (info->fbops->fb_setcolreg(start++,
238                                                       hred, hgreen, hblue,
239                                                       htransp, info))
240                                 break;
241                 }
242         }
243         if (rc == 0)
244                 fb_copy_cmap(cmap, &info->cmap);
245
246         return rc;
247 }
248
249 int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info)
250 {
251         int rc, size = cmap->len * sizeof(u16);
252         struct fb_cmap umap;
253
254         if (cmap->start < 0 || (!info->fbops->fb_setcolreg &&
255                                 !info->fbops->fb_setcmap))
256                 return -EINVAL;
257
258         memset(&umap, 0, sizeof(struct fb_cmap));
259         rc = fb_alloc_cmap(&umap, cmap->len, cmap->transp != NULL);
260         if (rc)
261                 return rc;
262         if (copy_from_user(umap.red, cmap->red, size) ||
263             copy_from_user(umap.green, cmap->green, size) ||
264             copy_from_user(umap.blue, cmap->blue, size) ||
265             (cmap->transp && copy_from_user(umap.transp, cmap->transp, size))) {
266                 fb_dealloc_cmap(&umap);
267                 return -EFAULT;
268         }
269         umap.start = cmap->start;
270         rc = fb_set_cmap(&umap, info);
271         fb_dealloc_cmap(&umap);
272         return rc;
273 }
274
275 /**
276  *      fb_default_cmap - get default colormap
277  *      @len: size of palette for a depth
278  *
279  *      Gets the default colormap for a specific screen depth.  @len
280  *      is the size of the palette for a particular screen depth.
281  *
282  *      Returns pointer to a frame buffer colormap structure.
283  *
284  */
285
286 const struct fb_cmap *fb_default_cmap(int len)
287 {
288     if (len <= 2)
289         return &default_2_colors;
290     if (len <= 4)
291         return &default_4_colors;
292     if (len <= 8)
293         return &default_8_colors;
294     return &default_16_colors;
295 }
296
297
298 /**
299  *      fb_invert_cmaps - invert all defaults colormaps
300  *
301  *      Invert all default colormaps.
302  *
303  */
304
305 void fb_invert_cmaps(void)
306 {
307     u_int i;
308
309     for (i = 0; i < ARRAY_SIZE(red2); i++) {
310         red2[i] = ~red2[i];
311         green2[i] = ~green2[i];
312         blue2[i] = ~blue2[i];
313     }
314     for (i = 0; i < ARRAY_SIZE(red4); i++) {
315         red4[i] = ~red4[i];
316         green4[i] = ~green4[i];
317         blue4[i] = ~blue4[i];
318     }
319     for (i = 0; i < ARRAY_SIZE(red8); i++) {
320         red8[i] = ~red8[i];
321         green8[i] = ~green8[i];
322         blue8[i] = ~blue8[i];
323     }
324     for (i = 0; i < ARRAY_SIZE(red16); i++) {
325         red16[i] = ~red16[i];
326         green16[i] = ~green16[i];
327         blue16[i] = ~blue16[i];
328     }
329 }
330
331
332     /*
333      *  Visible symbols for modules
334      */
335
336 EXPORT_SYMBOL(fb_alloc_cmap);
337 EXPORT_SYMBOL(fb_dealloc_cmap);
338 EXPORT_SYMBOL(fb_copy_cmap);
339 EXPORT_SYMBOL(fb_set_cmap);
340 EXPORT_SYMBOL(fb_default_cmap);
341 EXPORT_SYMBOL(fb_invert_cmaps);