Mercurial > hg > minimon
comparison vfb/vfb.c @ 2:bac8ed8d6eb9
add jpeg coding and test stuff
author | Peter Meerwald <pmeerw@pmeerw.net> |
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date | Sun, 08 May 2011 18:22:22 +0200 |
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1:111d4bbce605 | 2:bac8ed8d6eb9 |
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1 /* | |
2 * linux/drivers/video/vfb.c -- Virtual frame buffer device | |
3 * | |
4 * Copyright (C) 2002 James Simmons | |
5 * | |
6 * Copyright (C) 1997 Geert Uytterhoeven | |
7 * | |
8 * This file is subject to the terms and conditions of the GNU General Public | |
9 * License. See the file COPYING in the main directory of this archive for | |
10 * more details. | |
11 */ | |
12 | |
13 #include <linux/module.h> | |
14 #include <linux/kernel.h> | |
15 #include <linux/errno.h> | |
16 #include <linux/string.h> | |
17 #include <linux/mm.h> | |
18 #include <linux/vmalloc.h> | |
19 #include <linux/delay.h> | |
20 #include <linux/interrupt.h> | |
21 #include <linux/platform_device.h> | |
22 | |
23 #include <linux/fb.h> | |
24 #include <linux/init.h> | |
25 | |
26 /* | |
27 * RAM we reserve for the frame buffer. This defines the maximum screen | |
28 * size | |
29 * | |
30 * The default can be overridden if the driver is compiled as a module | |
31 */ | |
32 | |
33 #define VIDEOMEMSIZE (1*1024*1024) /* 1 MB */ | |
34 | |
35 static void *videomemory; | |
36 static u_long videomemorysize = VIDEOMEMSIZE; | |
37 module_param(videomemorysize, ulong, 0); | |
38 | |
39 /********************************************************************** | |
40 * | |
41 * Memory management | |
42 * | |
43 **********************************************************************/ | |
44 static void *rvmalloc(unsigned long size) | |
45 { | |
46 void *mem; | |
47 unsigned long adr; | |
48 | |
49 size = PAGE_ALIGN(size); | |
50 mem = vmalloc_32(size); | |
51 if (!mem) | |
52 return NULL; | |
53 | |
54 memset(mem, 0, size); /* Clear the ram out, no junk to the user */ | |
55 adr = (unsigned long) mem; | |
56 while (size > 0) { | |
57 SetPageReserved(vmalloc_to_page((void *)adr)); | |
58 adr += PAGE_SIZE; | |
59 size -= PAGE_SIZE; | |
60 } | |
61 | |
62 return mem; | |
63 } | |
64 | |
65 static void rvfree(void *mem, unsigned long size) | |
66 { | |
67 unsigned long adr; | |
68 | |
69 if (!mem) | |
70 return; | |
71 | |
72 adr = (unsigned long) mem; | |
73 while ((long) size > 0) { | |
74 ClearPageReserved(vmalloc_to_page((void *)adr)); | |
75 adr += PAGE_SIZE; | |
76 size -= PAGE_SIZE; | |
77 } | |
78 vfree(mem); | |
79 } | |
80 | |
81 static struct fb_var_screeninfo vfb_default __devinitdata = { | |
82 .xres = 640, | |
83 .yres = 480, | |
84 .xres_virtual = 640, | |
85 .yres_virtual = 480, | |
86 .bits_per_pixel = 8, | |
87 .red = { 0, 8, 0 }, | |
88 .green = { 0, 8, 0 }, | |
89 .blue = { 0, 8, 0 }, | |
90 .activate = FB_ACTIVATE_TEST, | |
91 .height = -1, | |
92 .width = -1, | |
93 .pixclock = 20000, | |
94 .left_margin = 64, | |
95 .right_margin = 64, | |
96 .upper_margin = 32, | |
97 .lower_margin = 32, | |
98 .hsync_len = 64, | |
99 .vsync_len = 2, | |
100 .vmode = FB_VMODE_NONINTERLACED, | |
101 }; | |
102 | |
103 static struct fb_fix_screeninfo vfb_fix __devinitdata = { | |
104 .id = "Virtual FB", | |
105 .type = FB_TYPE_PACKED_PIXELS, | |
106 .visual = FB_VISUAL_PSEUDOCOLOR, | |
107 .xpanstep = 1, | |
108 .ypanstep = 1, | |
109 .ywrapstep = 1, | |
110 .accel = FB_ACCEL_NONE, | |
111 }; | |
112 | |
113 static int vfb_enable __initdata = 0; /* disabled by default */ | |
114 module_param(vfb_enable, bool, 0); | |
115 | |
116 static int vfb_check_var(struct fb_var_screeninfo *var, | |
117 struct fb_info *info); | |
118 static int vfb_set_par(struct fb_info *info); | |
119 static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue, | |
120 u_int transp, struct fb_info *info); | |
121 static int vfb_pan_display(struct fb_var_screeninfo *var, | |
122 struct fb_info *info); | |
123 static int vfb_mmap(struct fb_info *info, | |
124 struct vm_area_struct *vma); | |
125 | |
126 static struct fb_ops vfb_ops = { | |
127 .fb_read = fb_sys_read, | |
128 .fb_write = fb_sys_write, | |
129 .fb_check_var = vfb_check_var, | |
130 .fb_set_par = vfb_set_par, | |
131 .fb_setcolreg = vfb_setcolreg, | |
132 .fb_pan_display = vfb_pan_display, | |
133 .fb_fillrect = sys_fillrect, | |
134 .fb_copyarea = sys_copyarea, | |
135 .fb_imageblit = sys_imageblit, | |
136 .fb_mmap = vfb_mmap, | |
137 }; | |
138 | |
139 /* | |
140 * Internal routines | |
141 */ | |
142 | |
143 static u_long get_line_length(int xres_virtual, int bpp) | |
144 { | |
145 u_long length; | |
146 | |
147 length = xres_virtual * bpp; | |
148 length = (length + 31) & ~31; | |
149 length >>= 3; | |
150 return (length); | |
151 } | |
152 | |
153 /* | |
154 * Setting the video mode has been split into two parts. | |
155 * First part, xxxfb_check_var, must not write anything | |
156 * to hardware, it should only verify and adjust var. | |
157 * This means it doesn't alter par but it does use hardware | |
158 * data from it to check this var. | |
159 */ | |
160 | |
161 static int vfb_check_var(struct fb_var_screeninfo *var, | |
162 struct fb_info *info) | |
163 { | |
164 u_long line_length; | |
165 | |
166 /* | |
167 * FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal! | |
168 * as FB_VMODE_SMOOTH_XPAN is only used internally | |
169 */ | |
170 | |
171 if (var->vmode & FB_VMODE_CONUPDATE) { | |
172 var->vmode |= FB_VMODE_YWRAP; | |
173 var->xoffset = info->var.xoffset; | |
174 var->yoffset = info->var.yoffset; | |
175 } | |
176 | |
177 /* | |
178 * Some very basic checks | |
179 */ | |
180 if (!var->xres) | |
181 var->xres = 1; | |
182 if (!var->yres) | |
183 var->yres = 1; | |
184 if (var->xres > var->xres_virtual) | |
185 var->xres_virtual = var->xres; | |
186 if (var->yres > var->yres_virtual) | |
187 var->yres_virtual = var->yres; | |
188 if (var->bits_per_pixel <= 1) | |
189 var->bits_per_pixel = 1; | |
190 else if (var->bits_per_pixel <= 8) | |
191 var->bits_per_pixel = 8; | |
192 else if (var->bits_per_pixel <= 16) | |
193 var->bits_per_pixel = 16; | |
194 else if (var->bits_per_pixel <= 24) | |
195 var->bits_per_pixel = 24; | |
196 else if (var->bits_per_pixel <= 32) | |
197 var->bits_per_pixel = 32; | |
198 else | |
199 return -EINVAL; | |
200 | |
201 if (var->xres_virtual < var->xoffset + var->xres) | |
202 var->xres_virtual = var->xoffset + var->xres; | |
203 if (var->yres_virtual < var->yoffset + var->yres) | |
204 var->yres_virtual = var->yoffset + var->yres; | |
205 | |
206 /* | |
207 * Memory limit | |
208 */ | |
209 line_length = | |
210 get_line_length(var->xres_virtual, var->bits_per_pixel); | |
211 if (line_length * var->yres_virtual > videomemorysize) | |
212 return -ENOMEM; | |
213 | |
214 /* | |
215 * Now that we checked it we alter var. The reason being is that the video | |
216 * mode passed in might not work but slight changes to it might make it | |
217 * work. This way we let the user know what is acceptable. | |
218 */ | |
219 switch (var->bits_per_pixel) { | |
220 case 1: | |
221 case 8: | |
222 var->red.offset = 0; | |
223 var->red.length = 8; | |
224 var->green.offset = 0; | |
225 var->green.length = 8; | |
226 var->blue.offset = 0; | |
227 var->blue.length = 8; | |
228 var->transp.offset = 0; | |
229 var->transp.length = 0; | |
230 break; | |
231 case 16: /* RGBA 5551 */ | |
232 if (var->transp.length) { | |
233 var->red.offset = 0; | |
234 var->red.length = 5; | |
235 var->green.offset = 5; | |
236 var->green.length = 5; | |
237 var->blue.offset = 10; | |
238 var->blue.length = 5; | |
239 var->transp.offset = 15; | |
240 var->transp.length = 1; | |
241 } else { /* RGB 565 */ | |
242 var->red.offset = 0; | |
243 var->red.length = 5; | |
244 var->green.offset = 5; | |
245 var->green.length = 6; | |
246 var->blue.offset = 11; | |
247 var->blue.length = 5; | |
248 var->transp.offset = 0; | |
249 var->transp.length = 0; | |
250 } | |
251 break; | |
252 case 24: /* RGB 888 */ | |
253 var->red.offset = 0; | |
254 var->red.length = 8; | |
255 var->green.offset = 8; | |
256 var->green.length = 8; | |
257 var->blue.offset = 16; | |
258 var->blue.length = 8; | |
259 var->transp.offset = 0; | |
260 var->transp.length = 0; | |
261 break; | |
262 case 32: /* RGBA 8888 */ | |
263 var->red.offset = 0; | |
264 var->red.length = 8; | |
265 var->green.offset = 8; | |
266 var->green.length = 8; | |
267 var->blue.offset = 16; | |
268 var->blue.length = 8; | |
269 var->transp.offset = 24; | |
270 var->transp.length = 8; | |
271 break; | |
272 } | |
273 var->red.msb_right = 0; | |
274 var->green.msb_right = 0; | |
275 var->blue.msb_right = 0; | |
276 var->transp.msb_right = 0; | |
277 | |
278 return 0; | |
279 } | |
280 | |
281 /* This routine actually sets the video mode. It's in here where we | |
282 * the hardware state info->par and fix which can be affected by the | |
283 * change in par. For this driver it doesn't do much. | |
284 */ | |
285 static int vfb_set_par(struct fb_info *info) | |
286 { | |
287 info->fix.line_length = get_line_length(info->var.xres_virtual, | |
288 info->var.bits_per_pixel); | |
289 return 0; | |
290 } | |
291 | |
292 /* | |
293 * Set a single color register. The values supplied are already | |
294 * rounded down to the hardware's capabilities (according to the | |
295 * entries in the var structure). Return != 0 for invalid regno. | |
296 */ | |
297 | |
298 static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue, | |
299 u_int transp, struct fb_info *info) | |
300 { | |
301 if (regno >= 256) /* no. of hw registers */ | |
302 return 1; | |
303 /* | |
304 * Program hardware... do anything you want with transp | |
305 */ | |
306 | |
307 /* grayscale works only partially under directcolor */ | |
308 if (info->var.grayscale) { | |
309 /* grayscale = 0.30*R + 0.59*G + 0.11*B */ | |
310 red = green = blue = | |
311 (red * 77 + green * 151 + blue * 28) >> 8; | |
312 } | |
313 | |
314 /* Directcolor: | |
315 * var->{color}.offset contains start of bitfield | |
316 * var->{color}.length contains length of bitfield | |
317 * {hardwarespecific} contains width of RAMDAC | |
318 * cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset) | |
319 * RAMDAC[X] is programmed to (red, green, blue) | |
320 * | |
321 * Pseudocolor: | |
322 * var->{color}.offset is 0 unless the palette index takes less than | |
323 * bits_per_pixel bits and is stored in the upper | |
324 * bits of the pixel value | |
325 * var->{color}.length is set so that 1 << length is the number of available | |
326 * palette entries | |
327 * cmap is not used | |
328 * RAMDAC[X] is programmed to (red, green, blue) | |
329 * | |
330 * Truecolor: | |
331 * does not use DAC. Usually 3 are present. | |
332 * var->{color}.offset contains start of bitfield | |
333 * var->{color}.length contains length of bitfield | |
334 * cmap is programmed to (red << red.offset) | (green << green.offset) | | |
335 * (blue << blue.offset) | (transp << transp.offset) | |
336 * RAMDAC does not exist | |
337 */ | |
338 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16) | |
339 switch (info->fix.visual) { | |
340 case FB_VISUAL_TRUECOLOR: | |
341 case FB_VISUAL_PSEUDOCOLOR: | |
342 red = CNVT_TOHW(red, info->var.red.length); | |
343 green = CNVT_TOHW(green, info->var.green.length); | |
344 blue = CNVT_TOHW(blue, info->var.blue.length); | |
345 transp = CNVT_TOHW(transp, info->var.transp.length); | |
346 break; | |
347 case FB_VISUAL_DIRECTCOLOR: | |
348 red = CNVT_TOHW(red, 8); /* expect 8 bit DAC */ | |
349 green = CNVT_TOHW(green, 8); | |
350 blue = CNVT_TOHW(blue, 8); | |
351 /* hey, there is bug in transp handling... */ | |
352 transp = CNVT_TOHW(transp, 8); | |
353 break; | |
354 } | |
355 #undef CNVT_TOHW | |
356 /* Truecolor has hardware independent palette */ | |
357 if (info->fix.visual == FB_VISUAL_TRUECOLOR) { | |
358 u32 v; | |
359 | |
360 if (regno >= 16) | |
361 return 1; | |
362 | |
363 v = (red << info->var.red.offset) | | |
364 (green << info->var.green.offset) | | |
365 (blue << info->var.blue.offset) | | |
366 (transp << info->var.transp.offset); | |
367 switch (info->var.bits_per_pixel) { | |
368 case 8: | |
369 break; | |
370 case 16: | |
371 ((u32 *) (info->pseudo_palette))[regno] = v; | |
372 break; | |
373 case 24: | |
374 case 32: | |
375 ((u32 *) (info->pseudo_palette))[regno] = v; | |
376 break; | |
377 } | |
378 return 0; | |
379 } | |
380 return 0; | |
381 } | |
382 | |
383 /* | |
384 * Pan or Wrap the Display | |
385 * | |
386 * This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag | |
387 */ | |
388 | |
389 static int vfb_pan_display(struct fb_var_screeninfo *var, | |
390 struct fb_info *info) | |
391 { | |
392 if (var->vmode & FB_VMODE_YWRAP) { | |
393 if (var->yoffset < 0 | |
394 || var->yoffset >= info->var.yres_virtual | |
395 || var->xoffset) | |
396 return -EINVAL; | |
397 } else { | |
398 if (var->xoffset + var->xres > info->var.xres_virtual || | |
399 var->yoffset + var->yres > info->var.yres_virtual) | |
400 return -EINVAL; | |
401 } | |
402 info->var.xoffset = var->xoffset; | |
403 info->var.yoffset = var->yoffset; | |
404 if (var->vmode & FB_VMODE_YWRAP) | |
405 info->var.vmode |= FB_VMODE_YWRAP; | |
406 else | |
407 info->var.vmode &= ~FB_VMODE_YWRAP; | |
408 return 0; | |
409 } | |
410 | |
411 /* | |
412 * Most drivers don't need their own mmap function | |
413 */ | |
414 | |
415 static int vfb_mmap(struct fb_info *info, | |
416 struct vm_area_struct *vma) | |
417 { | |
418 unsigned long start = vma->vm_start; | |
419 unsigned long size = vma->vm_end - vma->vm_start; | |
420 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; | |
421 unsigned long page, pos; | |
422 | |
423 if (offset + size > info->fix.smem_len) { | |
424 return -EINVAL; | |
425 } | |
426 | |
427 pos = (unsigned long)info->fix.smem_start + offset; | |
428 | |
429 while (size > 0) { | |
430 page = vmalloc_to_pfn((void *)pos); | |
431 if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) { | |
432 return -EAGAIN; | |
433 } | |
434 start += PAGE_SIZE; | |
435 pos += PAGE_SIZE; | |
436 if (size > PAGE_SIZE) | |
437 size -= PAGE_SIZE; | |
438 else | |
439 size = 0; | |
440 } | |
441 | |
442 vma->vm_flags |= VM_RESERVED; /* avoid to swap out this VMA */ | |
443 return 0; | |
444 | |
445 } | |
446 | |
447 #ifndef MODULE | |
448 /* | |
449 * The virtual framebuffer driver is only enabled if explicitly | |
450 * requested by passing 'video=vfb:' (or any actual options). | |
451 */ | |
452 static int __init vfb_setup(char *options) | |
453 { | |
454 char *this_opt; | |
455 | |
456 vfb_enable = 0; | |
457 | |
458 if (!options) | |
459 return 1; | |
460 | |
461 vfb_enable = 1; | |
462 | |
463 if (!*options) | |
464 return 1; | |
465 | |
466 while ((this_opt = strsep(&options, ",")) != NULL) { | |
467 if (!*this_opt) | |
468 continue; | |
469 /* Test disable for backwards compatibility */ | |
470 if (!strcmp(this_opt, "disable")) | |
471 vfb_enable = 0; | |
472 } | |
473 return 1; | |
474 } | |
475 #endif /* MODULE */ | |
476 | |
477 /* | |
478 * Initialisation | |
479 */ | |
480 | |
481 static int __devinit vfb_probe(struct platform_device *dev) | |
482 { | |
483 struct fb_info *info; | |
484 int retval = -ENOMEM; | |
485 | |
486 /* | |
487 * For real video cards we use ioremap. | |
488 */ | |
489 if (!(videomemory = rvmalloc(videomemorysize))) | |
490 return retval; | |
491 | |
492 /* | |
493 * VFB must clear memory to prevent kernel info | |
494 * leakage into userspace | |
495 * VGA-based drivers MUST NOT clear memory if | |
496 * they want to be able to take over vgacon | |
497 */ | |
498 memset(videomemory, 0, videomemorysize); | |
499 | |
500 info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev); | |
501 if (!info) | |
502 goto err; | |
503 | |
504 info->screen_base = (char __iomem *)videomemory; | |
505 info->fbops = &vfb_ops; | |
506 | |
507 retval = fb_find_mode(&info->var, info, NULL, | |
508 NULL, 0, NULL, 8); | |
509 | |
510 if (!retval || (retval == 4)) | |
511 info->var = vfb_default; | |
512 vfb_fix.smem_start = (unsigned long) videomemory; | |
513 vfb_fix.smem_len = videomemorysize; | |
514 info->fix = vfb_fix; | |
515 info->pseudo_palette = info->par; | |
516 info->par = NULL; | |
517 info->flags = FBINFO_FLAG_DEFAULT; | |
518 | |
519 retval = fb_alloc_cmap(&info->cmap, 256, 0); | |
520 if (retval < 0) | |
521 goto err1; | |
522 | |
523 retval = register_framebuffer(info); | |
524 if (retval < 0) | |
525 goto err2; | |
526 platform_set_drvdata(dev, info); | |
527 | |
528 printk(KERN_INFO | |
529 "fb%d: Virtual frame buffer device, using %ldK of video memory\n", | |
530 info->node, videomemorysize >> 10); | |
531 return 0; | |
532 err2: | |
533 fb_dealloc_cmap(&info->cmap); | |
534 err1: | |
535 framebuffer_release(info); | |
536 err: | |
537 rvfree(videomemory, videomemorysize); | |
538 return retval; | |
539 } | |
540 | |
541 static int vfb_remove(struct platform_device *dev) | |
542 { | |
543 struct fb_info *info = platform_get_drvdata(dev); | |
544 | |
545 if (info) { | |
546 unregister_framebuffer(info); | |
547 rvfree(videomemory, videomemorysize); | |
548 fb_dealloc_cmap(&info->cmap); | |
549 framebuffer_release(info); | |
550 } | |
551 return 0; | |
552 } | |
553 | |
554 static struct platform_driver vfb_driver = { | |
555 .probe = vfb_probe, | |
556 .remove = vfb_remove, | |
557 .driver = { | |
558 .name = "vfb", | |
559 }, | |
560 }; | |
561 | |
562 static struct platform_device *vfb_device; | |
563 | |
564 static int __init vfb_init(void) | |
565 { | |
566 int ret = 0; | |
567 | |
568 #ifndef MODULE | |
569 char *option = NULL; | |
570 | |
571 if (fb_get_options("vfb", &option)) | |
572 return -ENODEV; | |
573 vfb_setup(option); | |
574 #endif | |
575 | |
576 if (!vfb_enable) | |
577 return -ENXIO; | |
578 | |
579 ret = platform_driver_register(&vfb_driver); | |
580 | |
581 if (!ret) { | |
582 vfb_device = platform_device_alloc("vfb", 0); | |
583 | |
584 if (vfb_device) | |
585 ret = platform_device_add(vfb_device); | |
586 else | |
587 ret = -ENOMEM; | |
588 | |
589 if (ret) { | |
590 platform_device_put(vfb_device); | |
591 platform_driver_unregister(&vfb_driver); | |
592 } | |
593 } | |
594 | |
595 return ret; | |
596 } | |
597 | |
598 module_init(vfb_init); | |
599 | |
600 #ifdef MODULE | |
601 static void __exit vfb_exit(void) | |
602 { | |
603 platform_device_unregister(vfb_device); | |
604 platform_driver_unregister(&vfb_driver); | |
605 } | |
606 | |
607 module_exit(vfb_exit); | |
608 | |
609 MODULE_LICENSE("GPL"); | |
610 #endif /* MODULE */ |