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1/*
2 * linux/drivers/video/68328fb.c -- Low level implementation of the
3 * mc68x328 LCD frame buffer device
4 *
5 * Copyright (C) 2003 Georges Menie
6 *
7 * This driver assumes an already configured controller (e.g. from config.c)
8 * Keep the code clean of board specific initialization.
9 *
10 * This code has not been tested with colors, colormap management functions
11 * are minimal (no colormap data written to the 68328 registers...)
12 *
13 * initial version of this driver:
14 * Copyright (C) 1998,1999 Kenneth Albanowski <[email protected]>,
15 * The Silver Hammer Group, Ltd.
16 *
17 * this version is based on :
18 *
19 * linux/drivers/video/vfb.c -- Virtual frame buffer device
20 *
21 * Copyright (C) 2002 James Simmons
22 *
23 * Copyright (C) 1997 Geert Uytterhoeven
24 *
25 * This file is subject to the terms and conditions of the GNU General Public
26 * License. See the file COPYING in the main directory of this archive for
27 * more details.
28 */
29
30#include <linux/module.h>
31#include <linux/kernel.h>
32#include <linux/errno.h>
33#include <linux/string.h>
34#include <linux/mm.h>
35#include <linux/vmalloc.h>
36#include <linux/delay.h>
37#include <linux/interrupt.h>
38#include <linux/uaccess.h>
39#include <linux/fb.h>
40#include <linux/init.h>
41
42#if defined(CONFIG_M68VZ328)
43#include <asm/MC68VZ328.h>
44#elif defined(CONFIG_M68EZ328)
45#include <asm/MC68EZ328.h>
46#elif defined(CONFIG_M68328)
47#include <asm/MC68328.h>
48#else
49#error wrong architecture for the MC68x328 frame buffer device
50#endif
51
52static u_long videomemory;
53static u_long videomemorysize;
54
55static struct fb_info fb_info;
56static u32 mc68x328fb_pseudo_palette[16];
57
58static struct fb_var_screeninfo mc68x328fb_default __initdata = {
59 .red = { 0, 8, 0 },
60 .green = { 0, 8, 0 },
61 .blue = { 0, 8, 0 },
62 .activate = FB_ACTIVATE_TEST,
63 .height = -1,
64 .width = -1,
65 .pixclock = 20000,
66 .left_margin = 64,
67 .right_margin = 64,
68 .upper_margin = 32,
69 .lower_margin = 32,
70 .hsync_len = 64,
71 .vsync_len = 2,
72 .vmode = FB_VMODE_NONINTERLACED,
73};
74
75static const struct fb_fix_screeninfo mc68x328fb_fix __initconst = {
76 .id = "68328fb",
77 .type = FB_TYPE_PACKED_PIXELS,
78 .xpanstep = 1,
79 .ypanstep = 1,
80 .ywrapstep = 1,
81 .accel = FB_ACCEL_NONE,
82};
83
84 /*
85 * Interface used by the world
86 */
87static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
88 struct fb_info *info);
89static int mc68x328fb_set_par(struct fb_info *info);
90static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
91 u_int transp, struct fb_info *info);
92static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
93 struct fb_info *info);
94static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma);
95
96static const struct fb_ops mc68x328fb_ops = {
97 .owner = THIS_MODULE,
98 __FB_DEFAULT_IOMEM_OPS_RDWR,
99 .fb_check_var = mc68x328fb_check_var,
100 .fb_set_par = mc68x328fb_set_par,
101 .fb_setcolreg = mc68x328fb_setcolreg,
102 .fb_pan_display = mc68x328fb_pan_display,
103 __FB_DEFAULT_IOMEM_OPS_DRAW,
104 .fb_mmap = mc68x328fb_mmap,
105};
106
107 /*
108 * Internal routines
109 */
110
111static u_long get_line_length(int xres_virtual, int bpp)
112{
113 u_long length;
114
115 length = xres_virtual * bpp;
116 length = (length + 31) & ~31;
117 length >>= 3;
118 return (length);
119}
120
121 /*
122 * Setting the video mode has been split into two parts.
123 * First part, xxxfb_check_var, must not write anything
124 * to hardware, it should only verify and adjust var.
125 * This means it doesn't alter par but it does use hardware
126 * data from it to check this var.
127 */
128
129static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
130 struct fb_info *info)
131{
132 u_long line_length;
133
134 /*
135 * FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
136 * as FB_VMODE_SMOOTH_XPAN is only used internally
137 */
138
139 if (var->vmode & FB_VMODE_CONUPDATE) {
140 var->vmode |= FB_VMODE_YWRAP;
141 var->xoffset = info->var.xoffset;
142 var->yoffset = info->var.yoffset;
143 }
144
145 /*
146 * Some very basic checks
147 */
148 if (!var->xres)
149 var->xres = 1;
150 if (!var->yres)
151 var->yres = 1;
152 if (var->xres > var->xres_virtual)
153 var->xres_virtual = var->xres;
154 if (var->yres > var->yres_virtual)
155 var->yres_virtual = var->yres;
156 if (var->bits_per_pixel <= 1)
157 var->bits_per_pixel = 1;
158 else if (var->bits_per_pixel <= 8)
159 var->bits_per_pixel = 8;
160 else if (var->bits_per_pixel <= 16)
161 var->bits_per_pixel = 16;
162 else if (var->bits_per_pixel <= 24)
163 var->bits_per_pixel = 24;
164 else if (var->bits_per_pixel <= 32)
165 var->bits_per_pixel = 32;
166 else
167 return -EINVAL;
168
169 if (var->xres_virtual < var->xoffset + var->xres)
170 var->xres_virtual = var->xoffset + var->xres;
171 if (var->yres_virtual < var->yoffset + var->yres)
172 var->yres_virtual = var->yoffset + var->yres;
173
174 /*
175 * Memory limit
176 */
177 line_length =
178 get_line_length(var->xres_virtual, var->bits_per_pixel);
179 if (line_length * var->yres_virtual > videomemorysize)
180 return -ENOMEM;
181
182 /*
183 * Now that we checked it we alter var. The reason being is that the video
184 * mode passed in might not work but slight changes to it might make it
185 * work. This way we let the user know what is acceptable.
186 */
187 switch (var->bits_per_pixel) {
188 case 1:
189 var->red.offset = 0;
190 var->red.length = 1;
191 var->green.offset = 0;
192 var->green.length = 1;
193 var->blue.offset = 0;
194 var->blue.length = 1;
195 var->transp.offset = 0;
196 var->transp.length = 0;
197 break;
198 case 8:
199 var->red.offset = 0;
200 var->red.length = 8;
201 var->green.offset = 0;
202 var->green.length = 8;
203 var->blue.offset = 0;
204 var->blue.length = 8;
205 var->transp.offset = 0;
206 var->transp.length = 0;
207 break;
208 case 16: /* RGBA 5551 */
209 if (var->transp.length) {
210 var->red.offset = 0;
211 var->red.length = 5;
212 var->green.offset = 5;
213 var->green.length = 5;
214 var->blue.offset = 10;
215 var->blue.length = 5;
216 var->transp.offset = 15;
217 var->transp.length = 1;
218 } else { /* RGB 565 */
219 var->red.offset = 0;
220 var->red.length = 5;
221 var->green.offset = 5;
222 var->green.length = 6;
223 var->blue.offset = 11;
224 var->blue.length = 5;
225 var->transp.offset = 0;
226 var->transp.length = 0;
227 }
228 break;
229 case 24: /* RGB 888 */
230 var->red.offset = 0;
231 var->red.length = 8;
232 var->green.offset = 8;
233 var->green.length = 8;
234 var->blue.offset = 16;
235 var->blue.length = 8;
236 var->transp.offset = 0;
237 var->transp.length = 0;
238 break;
239 case 32: /* RGBA 8888 */
240 var->red.offset = 0;
241 var->red.length = 8;
242 var->green.offset = 8;
243 var->green.length = 8;
244 var->blue.offset = 16;
245 var->blue.length = 8;
246 var->transp.offset = 24;
247 var->transp.length = 8;
248 break;
249 }
250 var->red.msb_right = 0;
251 var->green.msb_right = 0;
252 var->blue.msb_right = 0;
253 var->transp.msb_right = 0;
254
255 return 0;
256}
257
258/* This routine actually sets the video mode. It's in here where we
259 * the hardware state info->par and fix which can be affected by the
260 * change in par. For this driver it doesn't do much.
261 */
262static int mc68x328fb_set_par(struct fb_info *info)
263{
264 info->fix.line_length = get_line_length(info->var.xres_virtual,
265 info->var.bits_per_pixel);
266 return 0;
267}
268
269 /*
270 * Set a single color register. The values supplied are already
271 * rounded down to the hardware's capabilities (according to the
272 * entries in the var structure). Return != 0 for invalid regno.
273 */
274
275static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
276 u_int transp, struct fb_info *info)
277{
278 if (regno >= 256) /* no. of hw registers */
279 return 1;
280 /*
281 * Program hardware... do anything you want with transp
282 */
283
284 /* grayscale works only partially under directcolor */
285 if (info->var.grayscale) {
286 /* grayscale = 0.30*R + 0.59*G + 0.11*B */
287 red = green = blue =
288 (red * 77 + green * 151 + blue * 28) >> 8;
289 }
290
291 /* Directcolor:
292 * var->{color}.offset contains start of bitfield
293 * var->{color}.length contains length of bitfield
294 * {hardwarespecific} contains width of RAMDAC
295 * cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
296 * RAMDAC[X] is programmed to (red, green, blue)
297 *
298 * Pseudocolor:
299 * uses offset = 0 && length = RAMDAC register width.
300 * var->{color}.offset is 0
301 * var->{color}.length contains width of DAC
302 * cmap is not used
303 * RAMDAC[X] is programmed to (red, green, blue)
304 * Truecolor:
305 * does not use DAC. Usually 3 are present.
306 * var->{color}.offset contains start of bitfield
307 * var->{color}.length contains length of bitfield
308 * cmap is programmed to (red << red.offset) | (green << green.offset) |
309 * (blue << blue.offset) | (transp << transp.offset)
310 * RAMDAC does not exist
311 */
312#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
313 switch (info->fix.visual) {
314 case FB_VISUAL_TRUECOLOR:
315 case FB_VISUAL_PSEUDOCOLOR:
316 red = CNVT_TOHW(red, info->var.red.length);
317 green = CNVT_TOHW(green, info->var.green.length);
318 blue = CNVT_TOHW(blue, info->var.blue.length);
319 transp = CNVT_TOHW(transp, info->var.transp.length);
320 break;
321 case FB_VISUAL_DIRECTCOLOR:
322 red = CNVT_TOHW(red, 8); /* expect 8 bit DAC */
323 green = CNVT_TOHW(green, 8);
324 blue = CNVT_TOHW(blue, 8);
325 /* hey, there is bug in transp handling... */
326 transp = CNVT_TOHW(transp, 8);
327 break;
328 }
329#undef CNVT_TOHW
330 /* Truecolor has hardware independent palette */
331 if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
332 u32 v;
333
334 if (regno >= 16)
335 return 1;
336
337 v = (red << info->var.red.offset) |
338 (green << info->var.green.offset) |
339 (blue << info->var.blue.offset) |
340 (transp << info->var.transp.offset);
341 switch (info->var.bits_per_pixel) {
342 case 8:
343 break;
344 case 16:
345 ((u32 *) (info->pseudo_palette))[regno] = v;
346 break;
347 case 24:
348 case 32:
349 ((u32 *) (info->pseudo_palette))[regno] = v;
350 break;
351 }
352 return 0;
353 }
354 return 0;
355}
356
357 /*
358 * Pan or Wrap the Display
359 *
360 * This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
361 */
362
363static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
364 struct fb_info *info)
365{
366 if (var->vmode & FB_VMODE_YWRAP) {
367 if (var->yoffset < 0
368 || var->yoffset >= info->var.yres_virtual
369 || var->xoffset)
370 return -EINVAL;
371 } else {
372 if (var->xoffset + info->var.xres > info->var.xres_virtual ||
373 var->yoffset + info->var.yres > info->var.yres_virtual)
374 return -EINVAL;
375 }
376 info->var.xoffset = var->xoffset;
377 info->var.yoffset = var->yoffset;
378 if (var->vmode & FB_VMODE_YWRAP)
379 info->var.vmode |= FB_VMODE_YWRAP;
380 else
381 info->var.vmode &= ~FB_VMODE_YWRAP;
382 return 0;
383}
384
385 /*
386 * Most drivers don't need their own mmap function
387 */
388
389static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
390{
391#ifndef MMU
392 /* this is uClinux (no MMU) specific code */
393
394 vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
395 vma->vm_start = videomemory;
396
397 return 0;
398#else
399 return -EINVAL;
400#endif
401}
402
403static int __init mc68x328fb_setup(char *options)
404{
405 if (!options || !*options)
406 return 1;
407 return 1;
408}
409
410 /*
411 * Initialisation
412 */
413
414static int __init mc68x328fb_init(void)
415{
416#ifndef MODULE
417 char *option = NULL;
418
419 if (fb_get_options("68328fb", &option))
420 return -ENODEV;
421 mc68x328fb_setup(option);
422#endif
423 /*
424 * initialize the default mode from the LCD controller registers
425 */
426 mc68x328fb_default.xres = LXMAX;
427 mc68x328fb_default.yres = LYMAX+1;
428 mc68x328fb_default.xres_virtual = mc68x328fb_default.xres;
429 mc68x328fb_default.yres_virtual = mc68x328fb_default.yres;
430 mc68x328fb_default.bits_per_pixel = 1 + (LPICF & 0x01);
431 videomemory = LSSA;
432 videomemorysize = (mc68x328fb_default.xres_virtual+7) / 8 *
433 mc68x328fb_default.yres_virtual * mc68x328fb_default.bits_per_pixel;
434
435 fb_info.screen_base = (void *)videomemory;
436 fb_info.fbops = &mc68x328fb_ops;
437 fb_info.var = mc68x328fb_default;
438 fb_info.fix = mc68x328fb_fix;
439 fb_info.fix.smem_start = videomemory;
440 fb_info.fix.smem_len = videomemorysize;
441 fb_info.fix.line_length =
442 get_line_length(mc68x328fb_default.xres_virtual, mc68x328fb_default.bits_per_pixel);
443 fb_info.fix.visual = (mc68x328fb_default.bits_per_pixel) == 1 ?
444 FB_VISUAL_MONO10 : FB_VISUAL_PSEUDOCOLOR;
445 if (fb_info.var.bits_per_pixel == 1) {
446 fb_info.var.red.length = fb_info.var.green.length = fb_info.var.blue.length = 1;
447 fb_info.var.red.offset = fb_info.var.green.offset = fb_info.var.blue.offset = 0;
448 }
449 fb_info.pseudo_palette = &mc68x328fb_pseudo_palette;
450 fb_info.flags = FBINFO_HWACCEL_YPAN;
451
452 if (fb_alloc_cmap(&fb_info.cmap, 256, 0))
453 return -ENOMEM;
454
455 if (register_framebuffer(&fb_info) < 0) {
456 fb_dealloc_cmap(&fb_info.cmap);
457 return -EINVAL;
458 }
459
460 fb_info(&fb_info, "%s frame buffer device\n", fb_info.fix.id);
461 fb_info(&fb_info, "%dx%dx%d at 0x%08lx\n",
462 mc68x328fb_default.xres_virtual,
463 mc68x328fb_default.yres_virtual,
464 1 << mc68x328fb_default.bits_per_pixel, videomemory);
465
466 return 0;
467}
468
469module_init(mc68x328fb_init);
470
471#ifdef MODULE
472
473static void __exit mc68x328fb_cleanup(void)
474{
475 unregister_framebuffer(&fb_info);
476 fb_dealloc_cmap(&fb_info.cmap);
477}
478
479module_exit(mc68x328fb_cleanup);
480
481MODULE_LICENSE("GPL");
482#endif /* MODULE */