drivers/video/fbdev/68328fb.c

   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 <kjahds@kjahds.com>,
  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
  52 static u_long videomemory;
  53 static u_long videomemorysize;
  54
  55 static struct fb_info fb_info;
  56 static u32 mc68x328fb_pseudo_palette[16];
  57
  58 static 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
  75 static struct fb_fix_screeninfo mc68x328fb_fix __initdata = {
  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      */
  87 int mc68x328fb_init(void);
  88 int mc68x328fb_setup(char *);
  89
  90 static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
  91                          struct fb_info *info);
  92 static int mc68x328fb_set_par(struct fb_info *info);
  93 static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
  94                          u_int transp, struct fb_info *info);
  95 static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
  96                            struct fb_info *info);
  97 static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma);
  98
  99 static struct fb_ops mc68x328fb_ops = {
 100         .fb_check_var   = mc68x328fb_check_var,
 101         .fb_set_par     = mc68x328fb_set_par,
 102         .fb_setcolreg   = mc68x328fb_setcolreg,
 103         .fb_pan_display = mc68x328fb_pan_display,
 104         .fb_fillrect    = cfb_fillrect,
 105         .fb_copyarea    = cfb_copyarea,
 106         .fb_imageblit   = cfb_imageblit,
 107         .fb_mmap        = mc68x328fb_mmap,
 108 };
 109
 110     /*
 111      *  Internal routines
 112      */
 113
 114 static u_long get_line_length(int xres_virtual, int bpp)
 115 {
 116         u_long length;
 117
 118         length = xres_virtual * bpp;
 119         length = (length + 31) & ~31;
 120         length >>= 3;
 121         return (length);
 122 }
 123
 124     /*
 125      *  Setting the video mode has been split into two parts.
 126      *  First part, xxxfb_check_var, must not write anything
 127      *  to hardware, it should only verify and adjust var.
 128      *  This means it doesn't alter par but it does use hardware
 129      *  data from it to check this var.
 130      */
 131
 132 static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
 133                          struct fb_info *info)
 134 {
 135         u_long line_length;
 136
 137         /*
 138          *  FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
 139          *  as FB_VMODE_SMOOTH_XPAN is only used internally
 140          */
 141
 142         if (var->vmode & FB_VMODE_CONUPDATE) {
 143                 var->vmode |= FB_VMODE_YWRAP;
 144                 var->xoffset = info->var.xoffset;
 145                 var->yoffset = info->var.yoffset;
 146         }
 147
 148         /*
 149          *  Some very basic checks
 150          */
 151         if (!var->xres)
 152                 var->xres = 1;
 153         if (!var->yres)
 154                 var->yres = 1;
 155         if (var->xres > var->xres_virtual)
 156                 var->xres_virtual = var->xres;
 157         if (var->yres > var->yres_virtual)
 158                 var->yres_virtual = var->yres;
 159         if (var->bits_per_pixel <= 1)
 160                 var->bits_per_pixel = 1;
 161         else if (var->bits_per_pixel <= 8)
 162                 var->bits_per_pixel = 8;
 163         else if (var->bits_per_pixel <= 16)
 164                 var->bits_per_pixel = 16;
 165         else if (var->bits_per_pixel <= 24)
 166                 var->bits_per_pixel = 24;
 167         else if (var->bits_per_pixel <= 32)
 168                 var->bits_per_pixel = 32;
 169         else
 170                 return -EINVAL;
 171
 172         if (var->xres_virtual < var->xoffset + var->xres)
 173                 var->xres_virtual = var->xoffset + var->xres;
 174         if (var->yres_virtual < var->yoffset + var->yres)
 175                 var->yres_virtual = var->yoffset + var->yres;
 176
 177         /*
 178          *  Memory limit
 179          */
 180         line_length =
 181             get_line_length(var->xres_virtual, var->bits_per_pixel);
 182         if (line_length * var->yres_virtual > videomemorysize)
 183                 return -ENOMEM;
 184
 185         /*
 186          * Now that we checked it we alter var. The reason being is that the video
 187          * mode passed in might not work but slight changes to it might make it
 188          * work. This way we let the user know what is acceptable.
 189          */
 190         switch (var->bits_per_pixel) {
 191         case 1:
 192                 var->red.offset = 0;
 193                 var->red.length = 1;
 194                 var->green.offset = 0;
 195                 var->green.length = 1;
 196                 var->blue.offset = 0;
 197                 var->blue.length = 1;
 198                 var->transp.offset = 0;
 199                 var->transp.length = 0;
 200                 break;
 201         case 8:
 202                 var->red.offset = 0;
 203                 var->red.length = 8;
 204                 var->green.offset = 0;
 205                 var->green.length = 8;
 206                 var->blue.offset = 0;
 207                 var->blue.length = 8;
 208                 var->transp.offset = 0;
 209                 var->transp.length = 0;
 210                 break;
 211         case 16:                /* RGBA 5551 */
 212                 if (var->transp.length) {
 213                         var->red.offset = 0;
 214                         var->red.length = 5;
 215                         var->green.offset = 5;
 216                         var->green.length = 5;
 217                         var->blue.offset = 10;
 218                         var->blue.length = 5;
 219                         var->transp.offset = 15;
 220                         var->transp.length = 1;
 221                 } else {        /* RGB 565 */
 222                         var->red.offset = 0;
 223                         var->red.length = 5;
 224                         var->green.offset = 5;
 225                         var->green.length = 6;
 226                         var->blue.offset = 11;
 227                         var->blue.length = 5;
 228                         var->transp.offset = 0;
 229                         var->transp.length = 0;
 230                 }
 231                 break;
 232         case 24:                /* RGB 888 */
 233                 var->red.offset = 0;
 234                 var->red.length = 8;
 235                 var->green.offset = 8;
 236                 var->green.length = 8;
 237                 var->blue.offset = 16;
 238                 var->blue.length = 8;
 239                 var->transp.offset = 0;
 240                 var->transp.length = 0;
 241                 break;
 242         case 32:                /* RGBA 8888 */
 243                 var->red.offset = 0;
 244                 var->red.length = 8;
 245                 var->green.offset = 8;
 246                 var->green.length = 8;
 247                 var->blue.offset = 16;
 248                 var->blue.length = 8;
 249                 var->transp.offset = 24;
 250                 var->transp.length = 8;
 251                 break;
 252         }
 253         var->red.msb_right = 0;
 254         var->green.msb_right = 0;
 255         var->blue.msb_right = 0;
 256         var->transp.msb_right = 0;
 257
 258         return 0;
 259 }
 260
 261 /* This routine actually sets the video mode. It's in here where we
 262  * the hardware state info->par and fix which can be affected by the
 263  * change in par. For this driver it doesn't do much.
 264  */
 265 static int mc68x328fb_set_par(struct fb_info *info)
 266 {
 267         info->fix.line_length = get_line_length(info->var.xres_virtual,
 268                                                 info->var.bits_per_pixel);
 269         return 0;
 270 }
 271
 272     /*
 273      *  Set a single color register. The values supplied are already
 274      *  rounded down to the hardware's capabilities (according to the
 275      *  entries in the var structure). Return != 0 for invalid regno.
 276      */
 277
 278 static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
 279                          u_int transp, struct fb_info *info)
 280 {
 281         if (regno >= 256)       /* no. of hw registers */
 282                 return 1;
 283         /*
 284          * Program hardware... do anything you want with transp
 285          */
 286
 287         /* grayscale works only partially under directcolor */
 288         if (info->var.grayscale) {
 289                 /* grayscale = 0.30*R + 0.59*G + 0.11*B */
 290                 red = green = blue =
 291                     (red * 77 + green * 151 + blue * 28) >> 8;
 292         }
 293
 294         /* Directcolor:
 295          *   var->{color}.offset contains start of bitfield
 296          *   var->{color}.length contains length of bitfield
 297          *   {hardwarespecific} contains width of RAMDAC
 298          *   cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
 299          *   RAMDAC[X] is programmed to (red, green, blue)
 300          *
 301          * Pseudocolor:
 302          *    uses offset = 0 && length = RAMDAC register width.
 303          *    var->{color}.offset is 0
 304          *    var->{color}.length contains width of DAC
 305          *    cmap is not used
 306          *    RAMDAC[X] is programmed to (red, green, blue)
 307          * Truecolor:
 308          *    does not use DAC. Usually 3 are present.
 309          *    var->{color}.offset contains start of bitfield
 310          *    var->{color}.length contains length of bitfield
 311          *    cmap is programmed to (red << red.offset) | (green << green.offset) |
 312          *                      (blue << blue.offset) | (transp << transp.offset)
 313          *    RAMDAC does not exist
 314          */
 315 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
 316         switch (info->fix.visual) {
 317         case FB_VISUAL_TRUECOLOR:
 318         case FB_VISUAL_PSEUDOCOLOR:
 319                 red = CNVT_TOHW(red, info->var.red.length);
 320                 green = CNVT_TOHW(green, info->var.green.length);
 321                 blue = CNVT_TOHW(blue, info->var.blue.length);
 322                 transp = CNVT_TOHW(transp, info->var.transp.length);
 323                 break;
 324         case FB_VISUAL_DIRECTCOLOR:
 325                 red = CNVT_TOHW(red, 8);        /* expect 8 bit DAC */
 326                 green = CNVT_TOHW(green, 8);
 327                 blue = CNVT_TOHW(blue, 8);
 328                 /* hey, there is bug in transp handling... */
 329                 transp = CNVT_TOHW(transp, 8);
 330                 break;
 331         }
 332 #undef CNVT_TOHW
 333         /* Truecolor has hardware independent palette */
 334         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
 335                 u32 v;
 336
 337                 if (regno >= 16)
 338                         return 1;
 339
 340                 v = (red << info->var.red.offset) |
 341                     (green << info->var.green.offset) |
 342                     (blue << info->var.blue.offset) |
 343                     (transp << info->var.transp.offset);
 344                 switch (info->var.bits_per_pixel) {
 345                 case 8:
 346                         break;
 347                 case 16:
 348                         ((u32 *) (info->pseudo_palette))[regno] = v;
 349                         break;
 350                 case 24:
 351                 case 32:
 352                         ((u32 *) (info->pseudo_palette))[regno] = v;
 353                         break;
 354                 }
 355                 return 0;
 356         }
 357         return 0;
 358 }
 359
 360     /*
 361      *  Pan or Wrap the Display
 362      *
 363      *  This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
 364      */
 365
 366 static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
 367                            struct fb_info *info)
 368 {
 369         if (var->vmode & FB_VMODE_YWRAP) {
 370                 if (var->yoffset < 0
 371                     || var->yoffset >= info->var.yres_virtual
 372                     || var->xoffset)
 373                         return -EINVAL;
 374         } else {
 375                 if (var->xoffset + info->var.xres > info->var.xres_virtual ||
 376                     var->yoffset + info->var.yres > info->var.yres_virtual)
 377                         return -EINVAL;
 378         }
 379         info->var.xoffset = var->xoffset;
 380         info->var.yoffset = var->yoffset;
 381         if (var->vmode & FB_VMODE_YWRAP)
 382                 info->var.vmode |= FB_VMODE_YWRAP;
 383         else
 384                 info->var.vmode &= ~FB_VMODE_YWRAP;
 385         return 0;
 386 }
 387
 388     /*
 389      *  Most drivers don't need their own mmap function
 390      */
 391
 392 static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 393 {
 394 #ifndef MMU
 395         /* this is uClinux (no MMU) specific code */
 396
 397         vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 398         vma->vm_start = videomemory;
 399
 400         return 0;
 401 #else
 402         return -EINVAL;
 403 #endif
 404 }
 405
 406 int __init mc68x328fb_setup(char *options)
 407 {
 408 #if 0
 409         char *this_opt;
 410 #endif
 411
 412         if (!options || !*options)
 413                 return 1;
 414 #if 0
 415         while ((this_opt = strsep(&options, ",")) != NULL) {
 416                 if (!*this_opt)
 417                         continue;
 418                 if (!strncmp(this_opt, "disable", 7))
 419                         mc68x328fb_enable = 0;
 420         }
 421 #endif
 422         return 1;
 423 }
 424
 425     /*
 426      *  Initialisation
 427      */
 428
 429 int __init mc68x328fb_init(void)
 430 {
 431 #ifndef MODULE
 432         char *option = NULL;
 433
 434         if (fb_get_options("68328fb", &option))
 435                 return -ENODEV;
 436         mc68x328fb_setup(option);
 437 #endif
 438         /*
 439          *  initialize the default mode from the LCD controller registers
 440          */
 441         mc68x328fb_default.xres = LXMAX;
 442         mc68x328fb_default.yres = LYMAX+1;
 443         mc68x328fb_default.xres_virtual = mc68x328fb_default.xres;
 444         mc68x328fb_default.yres_virtual = mc68x328fb_default.yres;
 445         mc68x328fb_default.bits_per_pixel = 1 + (LPICF & 0x01);
 446         videomemory = LSSA;
 447         videomemorysize = (mc68x328fb_default.xres_virtual+7) / 8 *
 448                 mc68x328fb_default.yres_virtual * mc68x328fb_default.bits_per_pixel;
 449
 450         fb_info.screen_base = (void *)videomemory;
 451         fb_info.fbops = &mc68x328fb_ops;
 452         fb_info.var = mc68x328fb_default;
 453         fb_info.fix = mc68x328fb_fix;
 454         fb_info.fix.smem_start = videomemory;
 455         fb_info.fix.smem_len = videomemorysize;
 456         fb_info.fix.line_length =
 457                 get_line_length(mc68x328fb_default.xres_virtual, mc68x328fb_default.bits_per_pixel);
 458         fb_info.fix.visual = (mc68x328fb_default.bits_per_pixel) == 1 ?
 459                 FB_VISUAL_MONO10 : FB_VISUAL_PSEUDOCOLOR;
 460         if (fb_info.var.bits_per_pixel == 1) {
 461                 fb_info.var.red.length = fb_info.var.green.length = fb_info.var.blue.length = 1;
 462                 fb_info.var.red.offset = fb_info.var.green.offset = fb_info.var.blue.offset = 0;
 463         }
 464         fb_info.pseudo_palette = &mc68x328fb_pseudo_palette;
 465         fb_info.flags = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
 466
 467         if (fb_alloc_cmap(&fb_info.cmap, 256, 0))
 468                 return -ENOMEM;
 469
 470         if (register_framebuffer(&fb_info) < 0) {
 471                 fb_dealloc_cmap(&fb_info.cmap);
 472                 return -EINVAL;
 473         }
 474
 475         fb_info(&fb_info, "%s frame buffer device\n", fb_info.fix.id);
 476         fb_info(&fb_info, "%dx%dx%d at 0x%08lx\n",
 477                 mc68x328fb_default.xres_virtual,
 478                 mc68x328fb_default.yres_virtual,
 479                 1 << mc68x328fb_default.bits_per_pixel, videomemory);
 480
 481         return 0;
 482 }
 483
 484 module_init(mc68x328fb_init);
 485
 486 #ifdef MODULE
 487
 488 static void __exit mc68x328fb_cleanup(void)
 489 {
 490         unregister_framebuffer(&fb_info);
 491         fb_dealloc_cmap(&fb_info.cmap);
 492 }
 493
 494 module_exit(mc68x328fb_cleanup);
 495
 496 MODULE_LICENSE("GPL");
 497 #endif                          /* MODULE */