drivers/video/xilinxfb.c

   1 /*
   2  * xilinxfb.c
   3  *
   4  * Xilinx TFT LCD frame buffer driver
   5  *
   6  * Author: MontaVista Software, Inc.
   7  *         source@mvista.com
   8  *
   9  * 2002-2007 (c) MontaVista Software, Inc.
  10  * 2007 (c) Secret Lab Technologies, Ltd.
  11  *
  12  * This file is licensed under the terms of the GNU General Public License
  13  * version 2.  This program is licensed "as is" without any warranty of any
  14  * kind, whether express or implied.
  15  */
  16
  17 /*
  18  * This driver was based on au1100fb.c by MontaVista rewritten for 2.6
  19  * by Embedded Alley Solutions <source@embeddedalley.com>, which in turn
  20  * was based on skeletonfb.c, Skeleton for a frame buffer device by
  21  * Geert Uytterhoeven.
  22  */
  23
  24 #include <linux/device.h>
  25 #include <linux/module.h>
  26 #include <linux/kernel.h>
  27 #include <linux/version.h>
  28 #include <linux/errno.h>
  29 #include <linux/string.h>
  30 #include <linux/mm.h>
  31 #include <linux/fb.h>
  32 #include <linux/init.h>
  33 #include <linux/dma-mapping.h>
  34 #include <linux/platform_device.h>
  35 #if defined(CONFIG_OF)
  36 #include <linux/of_device.h>
  37 #include <linux/of_platform.h>
  38 #endif
  39 #include <asm/io.h>
  40 #include <linux/xilinxfb.h>
  41
  42 #define DRIVER_NAME             "xilinxfb"
  43 #define DRIVER_DESCRIPTION      "Xilinx TFT LCD frame buffer driver"
  44
  45 /*
  46  * Xilinx calls it "PLB TFT LCD Controller" though it can also be used for
  47  * the VGA port on the Xilinx ML40x board. This is a hardware display controller
  48  * for a 640x480 resolution TFT or VGA screen.
  49  *
  50  * The interface to the framebuffer is nice and simple.  There are two
  51  * control registers.  The first tells the LCD interface where in memory
  52  * the frame buffer is (only the 11 most significant bits are used, so
  53  * don't start thinking about scrolling).  The second allows the LCD to
  54  * be turned on or off as well as rotated 180 degrees.
  55  */
  56 #define NUM_REGS        2
  57 #define REG_FB_ADDR     0
  58 #define REG_CTRL        1
  59 #define REG_CTRL_ENABLE  0x0001
  60 #define REG_CTRL_ROTATE  0x0002
  61
  62 /*
  63  * The hardware only handles a single mode: 640x480 24 bit true
  64  * color. Each pixel gets a word (32 bits) of memory.  Within each word,
  65  * the 8 most significant bits are ignored, the next 8 bits are the red
  66  * level, the next 8 bits are the green level and the 8 least
  67  * significant bits are the blue level.  Each row of the LCD uses 1024
  68  * words, but only the first 640 pixels are displayed with the other 384
  69  * words being ignored.  There are 480 rows.
  70  */
  71 #define BYTES_PER_PIXEL 4
  72 #define BITS_PER_PIXEL  (BYTES_PER_PIXEL * 8)
  73 #define XRES            640
  74 #define YRES            480
  75 #define XRES_VIRTUAL    1024
  76 #define YRES_VIRTUAL    YRES
  77 #define LINE_LENGTH     (XRES_VIRTUAL * BYTES_PER_PIXEL)
  78 #define FB_SIZE         (YRES_VIRTUAL * LINE_LENGTH)
  79
  80 #define RED_SHIFT       16
  81 #define GREEN_SHIFT     8
  82 #define BLUE_SHIFT      0
  83
  84 #define PALETTE_ENTRIES_NO      16      /* passed to fb_alloc_cmap() */
  85
  86 /*
  87  * Default xilinxfb configuration
  88  */
  89 static struct xilinxfb_platform_data xilinx_fb_default_pdata = {
  90 };
  91
  92 /*
  93  * Here are the default fb_fix_screeninfo and fb_var_screeninfo structures
  94  */
  95 static struct fb_fix_screeninfo xilinx_fb_fix = {
  96         .id =           "Xilinx",
  97         .type =         FB_TYPE_PACKED_PIXELS,
  98         .visual =       FB_VISUAL_TRUECOLOR,
  99         .smem_len =     FB_SIZE,
 100         .line_length =  LINE_LENGTH,
 101         .accel =        FB_ACCEL_NONE
 102 };
 103
 104 static struct fb_var_screeninfo xilinx_fb_var = {
 105         .xres =                 XRES,
 106         .yres =                 YRES,
 107         .xres_virtual =         XRES_VIRTUAL,
 108         .yres_virtual =         YRES_VIRTUAL,
 109
 110         .bits_per_pixel =       BITS_PER_PIXEL,
 111
 112         .red =          { RED_SHIFT, 8, 0 },
 113         .green =        { GREEN_SHIFT, 8, 0 },
 114         .blue =         { BLUE_SHIFT, 8, 0 },
 115         .transp =       { 0, 0, 0 },
 116
 117         .activate =     FB_ACTIVATE_NOW
 118 };
 119
 120 struct xilinxfb_drvdata {
 121
 122         struct fb_info  info;           /* FB driver info record */
 123
 124         u32             regs_phys;      /* phys. address of the control registers */
 125         u32 __iomem     *regs;          /* virt. address of the control registers */
 126
 127         void            *fb_virt;       /* virt. address of the frame buffer */
 128         dma_addr_t      fb_phys;        /* phys. address of the frame buffer */
 129
 130         u32             reg_ctrl_default;
 131
 132         u32             pseudo_palette[PALETTE_ENTRIES_NO];
 133                                         /* Fake palette of 16 colors */
 134 };
 135
 136 #define to_xilinxfb_drvdata(_info) \
 137         container_of(_info, struct xilinxfb_drvdata, info)
 138
 139 /*
 140  * The LCD controller has DCR interface to its registers, but all
 141  * the boards and configurations the driver has been tested with
 142  * use opb2dcr bridge. So the registers are seen as memory mapped.
 143  * This macro is to make it simple to add the direct DCR access
 144  * when it's needed.
 145  */
 146 #define xilinx_fb_out_be32(driverdata, offset, val) \
 147         out_be32(driverdata->regs + offset, val)
 148
 149 static int
 150 xilinx_fb_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue,
 151         unsigned transp, struct fb_info *fbi)
 152 {
 153         u32 *palette = fbi->pseudo_palette;
 154
 155         if (regno >= PALETTE_ENTRIES_NO)
 156                 return -EINVAL;
 157
 158         if (fbi->var.grayscale) {
 159                 /* Convert color to grayscale.
 160                  * grayscale = 0.30*R + 0.59*G + 0.11*B */
 161                 red = green = blue =
 162                         (red * 77 + green * 151 + blue * 28 + 127) >> 8;
 163         }
 164
 165         /* fbi->fix.visual is always FB_VISUAL_TRUECOLOR */
 166
 167         /* We only handle 8 bits of each color. */
 168         red >>= 8;
 169         green >>= 8;
 170         blue >>= 8;
 171         palette[regno] = (red << RED_SHIFT) | (green << GREEN_SHIFT) |
 172                          (blue << BLUE_SHIFT);
 173
 174         return 0;
 175 }
 176
 177 static int
 178 xilinx_fb_blank(int blank_mode, struct fb_info *fbi)
 179 {
 180         struct xilinxfb_drvdata *drvdata = to_xilinxfb_drvdata(fbi);
 181
 182         switch (blank_mode) {
 183         case FB_BLANK_UNBLANK:
 184                 /* turn on panel */
 185                 xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
 186                 break;
 187
 188         case FB_BLANK_NORMAL:
 189         case FB_BLANK_VSYNC_SUSPEND:
 190         case FB_BLANK_HSYNC_SUSPEND:
 191         case FB_BLANK_POWERDOWN:
 192                 /* turn off panel */
 193                 xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
 194         default:
 195                 break;
 196
 197         }
 198         return 0; /* success */
 199 }
 200
 201 static struct fb_ops xilinxfb_ops =
 202 {
 203         .owner                  = THIS_MODULE,
 204         .fb_setcolreg           = xilinx_fb_setcolreg,
 205         .fb_blank               = xilinx_fb_blank,
 206         .fb_fillrect            = cfb_fillrect,
 207         .fb_copyarea            = cfb_copyarea,
 208         .fb_imageblit           = cfb_imageblit,
 209 };
 210
 211 /* ---------------------------------------------------------------------
 212  * Bus independent setup/teardown
 213  */
 214
 215 static int xilinxfb_assign(struct device *dev, unsigned long physaddr,
 216                            struct xilinxfb_platform_data *pdata)
 217 {
 218         struct xilinxfb_drvdata *drvdata;
 219         int rc;
 220
 221         /* Allocate the driver data region */
 222         drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
 223         if (!drvdata) {
 224                 dev_err(dev, "Couldn't allocate device private record\n");
 225                 return -ENOMEM;
 226         }
 227         dev_set_drvdata(dev, drvdata);
 228
 229         /* Map the control registers in */
 230         if (!request_mem_region(physaddr, 8, DRIVER_NAME)) {
 231                 dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
 232                         physaddr);
 233                 rc = -ENODEV;
 234                 goto err_region;
 235         }
 236         drvdata->regs_phys = physaddr;
 237         drvdata->regs = ioremap(physaddr, 8);
 238         if (!drvdata->regs) {
 239                 dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
 240                         physaddr);
 241                 rc = -ENODEV;
 242                 goto err_map;
 243         }
 244
 245         /* Allocate the framebuffer memory */
 246         drvdata->fb_virt = dma_alloc_coherent(dev, PAGE_ALIGN(FB_SIZE),
 247                                 &drvdata->fb_phys, GFP_KERNEL);
 248         if (!drvdata->fb_virt) {
 249                 dev_err(dev, "Could not allocate frame buffer memory\n");
 250                 rc = -ENOMEM;
 251                 goto err_fbmem;
 252         }
 253
 254         /* Clear (turn to black) the framebuffer */
 255         memset_io((void __iomem *)drvdata->fb_virt, 0, FB_SIZE);
 256
 257         /* Tell the hardware where the frame buffer is */
 258         xilinx_fb_out_be32(drvdata, REG_FB_ADDR, drvdata->fb_phys);
 259
 260         /* Turn on the display */
 261         drvdata->reg_ctrl_default = REG_CTRL_ENABLE;
 262         if (pdata->rotate_screen)
 263                 drvdata->reg_ctrl_default |= REG_CTRL_ROTATE;
 264         xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
 265
 266         /* Fill struct fb_info */
 267         drvdata->info.device = dev;
 268         drvdata->info.screen_base = (void __iomem *)drvdata->fb_virt;
 269         drvdata->info.fbops = &xilinxfb_ops;
 270         drvdata->info.fix = xilinx_fb_fix;
 271         drvdata->info.fix.smem_start = drvdata->fb_phys;
 272         drvdata->info.pseudo_palette = drvdata->pseudo_palette;
 273         drvdata->info.flags = FBINFO_DEFAULT;
 274         drvdata->info.var = xilinx_fb_var;
 275
 276         xilinx_fb_var.height = pdata->screen_height_mm;
 277         xilinx_fb_var.width = pdata->screen_width_mm;
 278
 279         /* Allocate a colour map */
 280         rc = fb_alloc_cmap(&drvdata->info.cmap, PALETTE_ENTRIES_NO, 0);
 281         if (rc) {
 282                 dev_err(dev, "Fail to allocate colormap (%d entries)\n",
 283                         PALETTE_ENTRIES_NO);
 284                 goto err_cmap;
 285         }
 286
 287         /* Register new frame buffer */
 288         rc = register_framebuffer(&drvdata->info);
 289         if (rc) {
 290                 dev_err(dev, "Could not register frame buffer\n");
 291                 goto err_regfb;
 292         }
 293
 294         /* Put a banner in the log (for DEBUG) */
 295         dev_dbg(dev, "regs: phys=%lx, virt=%p\n", physaddr, drvdata->regs);
 296         dev_dbg(dev, "fb: phys=%p, virt=%p, size=%x\n",
 297                 (void*)drvdata->fb_phys, drvdata->fb_virt, FB_SIZE);
 298         return 0;       /* success */
 299
 300 err_regfb:
 301         fb_dealloc_cmap(&drvdata->info.cmap);
 302
 303 err_cmap:
 304         dma_free_coherent(dev, PAGE_ALIGN(FB_SIZE), drvdata->fb_virt,
 305                 drvdata->fb_phys);
 306         /* Turn off the display */
 307         xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
 308
 309 err_fbmem:
 310         iounmap(drvdata->regs);
 311
 312 err_map:
 313         release_mem_region(physaddr, 8);
 314
 315 err_region:
 316         kfree(drvdata);
 317         dev_set_drvdata(dev, NULL);
 318
 319         return rc;
 320 }
 321
 322 static int xilinxfb_release(struct device *dev)
 323 {
 324         struct xilinxfb_drvdata *drvdata = dev_get_drvdata(dev);
 325
 326 #if !defined(CONFIG_FRAMEBUFFER_CONSOLE) && defined(CONFIG_LOGO)
 327         xilinx_fb_blank(VESA_POWERDOWN, &drvdata->info);
 328 #endif
 329
 330         unregister_framebuffer(&drvdata->info);
 331
 332         fb_dealloc_cmap(&drvdata->info.cmap);
 333
 334         dma_free_coherent(dev, PAGE_ALIGN(FB_SIZE), drvdata->fb_virt,
 335                 drvdata->fb_phys);
 336
 337         /* Turn off the display */
 338         xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
 339         iounmap(drvdata->regs);
 340
 341         release_mem_region(drvdata->regs_phys, 8);
 342
 343         kfree(drvdata);
 344         dev_set_drvdata(dev, NULL);
 345
 346         return 0;
 347 }
 348
 349 /* ---------------------------------------------------------------------
 350  * Platform bus binding
 351  */
 352
 353 static int
 354 xilinxfb_platform_probe(struct platform_device *pdev)
 355 {
 356         struct xilinxfb_platform_data *pdata;
 357         struct resource *res;
 358
 359         /* Find the registers address */
 360         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 361         if (!res) {
 362                 dev_err(&pdev->dev, "Couldn't get registers resource\n");
 363                 return -ENODEV;
 364         }
 365
 366         /* If a pdata structure is provided, then extract the parameters */
 367         if (pdev->dev.platform_data)
 368                 pdata = pdev->dev.platform_data;
 369         else
 370                 pdata = &xilinx_fb_default_pdata;
 371
 372         return xilinxfb_assign(&pdev->dev, res->start, pdata);
 373 }
 374
 375 static int
 376 xilinxfb_platform_remove(struct platform_device *pdev)
 377 {
 378         return xilinxfb_release(&pdev->dev);
 379 }
 380
 381
 382 static struct platform_driver xilinxfb_platform_driver = {
 383         .probe          = xilinxfb_platform_probe,
 384         .remove         = xilinxfb_platform_remove,
 385         .driver = {
 386                 .owner = THIS_MODULE,
 387                 .name = DRIVER_NAME,
 388         },
 389 };
 390
 391 /* ---------------------------------------------------------------------
 392  * OF bus binding
 393  */
 394
 395 #if defined(CONFIG_OF)
 396 static int __devinit
 397 xilinxfb_of_probe(struct of_device *op, const struct of_device_id *match)
 398 {
 399         struct resource res;
 400         const u32 *prop;
 401         struct xilinxfb_platform_data pdata;
 402         int size, rc;
 403
 404         /* Copy with the default pdata (not a ptr reference!) */
 405         pdata = xilinx_fb_default_pdata;
 406
 407         dev_dbg(&op->dev, "xilinxfb_of_probe(%p, %p)\n", op, match);
 408
 409         rc = of_address_to_resource(op->node, 0, &res);
 410         if (rc) {
 411                 dev_err(&op->dev, "invalid address\n");
 412                 return rc;
 413         }
 414
 415         prop = of_get_property(op->node, "display-number", &size);
 416         if ((prop) && (size >= sizeof(u32)*2)) {
 417                 pdata.screen_width_mm = prop[0];
 418                 pdata.screen_height_mm = prop[1];
 419         }
 420
 421         if (of_find_property(op->node, "rotate-display", NULL))
 422                 pdata.rotate_screen = 1;
 423
 424         return xilinxfb_assign(&op->dev, res.start, &pdata);
 425 }
 426
 427 static int __devexit xilinxfb_of_remove(struct of_device *op)
 428 {
 429         return xilinxfb_release(&op->dev);
 430 }
 431
 432 /* Match table for of_platform binding */
 433 static struct of_device_id __devinit xilinxfb_of_match[] = {
 434         { .compatible = "xilinx,ml300-fb", },
 435         {},
 436 };
 437 MODULE_DEVICE_TABLE(of, xilinxfb_of_match);
 438
 439 static struct of_platform_driver xilinxfb_of_driver = {
 440         .owner = THIS_MODULE,
 441         .name = DRIVER_NAME,
 442         .match_table = xilinxfb_of_match,
 443         .probe = xilinxfb_of_probe,
 444         .remove = __devexit_p(xilinxfb_of_remove),
 445         .driver = {
 446                 .name = DRIVER_NAME,
 447         },
 448 };
 449
 450 /* Registration helpers to keep the number of #ifdefs to a minimum */
 451 static inline int __init xilinxfb_of_register(void)
 452 {
 453         pr_debug("xilinxfb: calling of_register_platform_driver()\n");
 454         return of_register_platform_driver(&xilinxfb_of_driver);
 455 }
 456
 457 static inline void __exit xilinxfb_of_unregister(void)
 458 {
 459         of_unregister_platform_driver(&xilinxfb_of_driver);
 460 }
 461 #else /* CONFIG_OF */
 462 /* CONFIG_OF not enabled; do nothing helpers */
 463 static inline int __init xilinxfb_of_register(void) { return 0; }
 464 static inline void __exit xilinxfb_of_unregister(void) { }
 465 #endif /* CONFIG_OF */
 466
 467 /* ---------------------------------------------------------------------
 468  * Module setup and teardown
 469  */
 470
 471 static int __init
 472 xilinxfb_init(void)
 473 {
 474         int rc;
 475         rc = xilinxfb_of_register();
 476         if (rc)
 477                 return rc;
 478
 479         rc = platform_driver_register(&xilinxfb_platform_driver);
 480         if (rc)
 481                 xilinxfb_of_unregister();
 482
 483         return rc;
 484 }
 485
 486 static void __exit
 487 xilinxfb_cleanup(void)
 488 {
 489         platform_driver_unregister(&xilinxfb_platform_driver);
 490         xilinxfb_of_unregister();
 491 }
 492
 493 module_init(xilinxfb_init);
 494 module_exit(xilinxfb_cleanup);
 495
 496 MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
 497 MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
 498 MODULE_LICENSE("GPL");