drivers/video/vt8500lcdfb.c

   1 /*
   2  *  linux/drivers/video/vt8500lcdfb.c
   3  *
   4  *  Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
   5  *
   6  * Based on skeletonfb.c and pxafb.c
   7  *
   8  * This software is licensed under the terms of the GNU General Public
   9  * License version 2, as published by the Free Software Foundation, and
  10  * may be copied, distributed, and modified under those terms.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/errno.h>
  21 #include <linux/string.h>
  22 #include <linux/mm.h>
  23 #include <linux/slab.h>
  24 #include <linux/delay.h>
  25 #include <linux/fb.h>
  26 #include <linux/init.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/io.h>
  29 #include <linux/dma-mapping.h>
  30 #include <linux/platform_device.h>
  31 #include <linux/wait.h>
  32
  33 #include "vt8500lcdfb.h"
  34 #include "wmt_ge_rops.h"
  35
  36 #ifdef CONFIG_OF
  37 #include <linux/of.h>
  38 #include <linux/of_fdt.h>
  39 #include <linux/memblock.h>
  40 #endif
  41
  42
  43 #define to_vt8500lcd_info(__info) container_of(__info, \
  44                                                 struct vt8500lcd_info, fb)
  45
  46 static int vt8500lcd_set_par(struct fb_info *info)
  47 {
  48         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
  49         int reg_bpp = 5; /* 16bpp */
  50         int i;
  51         unsigned long control0;
  52
  53         if (!fbi)
  54                 return -EINVAL;
  55
  56         if (info->var.bits_per_pixel <= 8) {
  57                 /* palettized */
  58                 info->var.red.offset    = 0;
  59                 info->var.red.length    = info->var.bits_per_pixel;
  60                 info->var.red.msb_right = 0;
  61
  62                 info->var.green.offset  = 0;
  63                 info->var.green.length  = info->var.bits_per_pixel;
  64                 info->var.green.msb_right = 0;
  65
  66                 info->var.blue.offset   = 0;
  67                 info->var.blue.length   = info->var.bits_per_pixel;
  68                 info->var.blue.msb_right = 0;
  69
  70                 info->var.transp.offset = 0;
  71                 info->var.transp.length = 0;
  72                 info->var.transp.msb_right = 0;
  73
  74                 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
  75                 info->fix.line_length = info->var.xres_virtual /
  76                                                 (8/info->var.bits_per_pixel);
  77         } else {
  78                 /* non-palettized */
  79                 info->var.transp.offset = 0;
  80                 info->var.transp.length = 0;
  81                 info->var.transp.msb_right = 0;
  82
  83                 if (info->var.bits_per_pixel == 16) {
  84                         /* RGB565 */
  85                         info->var.red.offset = 11;
  86                         info->var.red.length = 5;
  87                         info->var.red.msb_right = 0;
  88                         info->var.green.offset = 5;
  89                         info->var.green.length = 6;
  90                         info->var.green.msb_right = 0;
  91                         info->var.blue.offset = 0;
  92                         info->var.blue.length = 5;
  93                         info->var.blue.msb_right = 0;
  94                 } else {
  95                         /* Equal depths per channel */
  96                         info->var.red.offset = info->var.bits_per_pixel
  97                                                         * 2 / 3;
  98                         info->var.red.length = info->var.bits_per_pixel / 3;
  99                         info->var.red.msb_right = 0;
 100                         info->var.green.offset = info->var.bits_per_pixel / 3;
 101                         info->var.green.length = info->var.bits_per_pixel / 3;
 102                         info->var.green.msb_right = 0;
 103                         info->var.blue.offset = 0;
 104                         info->var.blue.length = info->var.bits_per_pixel / 3;
 105                         info->var.blue.msb_right = 0;
 106                 }
 107
 108                 info->fix.visual = FB_VISUAL_TRUECOLOR;
 109                 info->fix.line_length = info->var.bits_per_pixel > 16 ?
 110                                         info->var.xres_virtual << 2 :
 111                                         info->var.xres_virtual << 1;
 112         }
 113
 114         for (i = 0; i < 8; i++) {
 115                 if (bpp_values[i] == info->var.bits_per_pixel) {
 116                         reg_bpp = i;
 117                         continue;
 118                 }
 119         }
 120
 121         control0 = readl(fbi->regbase) & ~0xf;
 122         writel(0, fbi->regbase);
 123         while (readl(fbi->regbase + 0x38) & 0x10)
 124                 /* wait */;
 125         writel((((info->var.hsync_len - 1) & 0x3f) << 26)
 126                 | ((info->var.left_margin & 0xff) << 18)
 127                 | (((info->var.xres - 1) & 0x3ff) << 8)
 128                 | (info->var.right_margin & 0xff), fbi->regbase + 0x4);
 129         writel((((info->var.vsync_len - 1) & 0x3f) << 26)
 130                 | ((info->var.upper_margin & 0xff) << 18)
 131                 | (((info->var.yres - 1) & 0x3ff) << 8)
 132                 | (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
 133         writel((((info->var.yres - 1) & 0x400) << 2)
 134                 | ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
 135         writel(0x80000000, fbi->regbase + 0x20);
 136         writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
 137
 138         return 0;
 139 }
 140
 141 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
 142 {
 143         chan &= 0xffff;
 144         chan >>= 16 - bf->length;
 145         return chan << bf->offset;
 146 }
 147
 148 static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
 149                            unsigned blue, unsigned transp,
 150                            struct fb_info *info) {
 151         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 152         int ret = 1;
 153         unsigned int val;
 154         if (regno >= 256)
 155                 return -EINVAL;
 156
 157         if (info->var.grayscale)
 158                 red = green = blue =
 159                         (19595 * red + 38470 * green + 7471 * blue) >> 16;
 160
 161         switch (fbi->fb.fix.visual) {
 162         case FB_VISUAL_TRUECOLOR:
 163                 if (regno < 16) {
 164                         u32 *pal = fbi->fb.pseudo_palette;
 165
 166                         val  = chan_to_field(red, &fbi->fb.var.red);
 167                         val |= chan_to_field(green, &fbi->fb.var.green);
 168                         val |= chan_to_field(blue, &fbi->fb.var.blue);
 169
 170                         pal[regno] = val;
 171                         ret = 0;
 172                 }
 173                 break;
 174
 175         case FB_VISUAL_STATIC_PSEUDOCOLOR:
 176         case FB_VISUAL_PSEUDOCOLOR:
 177                 writew((red & 0xf800)
 178                       | ((green >> 5) & 0x7e0)
 179                       | ((blue >> 11) & 0x1f),
 180                        fbi->palette_cpu + sizeof(u16) * regno);
 181                 break;
 182         }
 183
 184         return ret;
 185 }
 186
 187 static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
 188                          unsigned long arg)
 189 {
 190         int ret = 0;
 191         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 192
 193         if (cmd == FBIO_WAITFORVSYNC) {
 194                 /* Unmask End of Frame interrupt */
 195                 writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
 196                 ret = wait_event_interruptible_timeout(fbi->wait,
 197                         readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
 198                 /* Mask back to reduce unwanted interrupt traffic */
 199                 writel(0xffffffff, fbi->regbase + 0x3c);
 200                 if (ret < 0)
 201                         return ret;
 202                 if (ret == 0)
 203                         return -ETIMEDOUT;
 204         }
 205
 206         return ret;
 207 }
 208
 209 static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
 210                                 struct fb_info *info)
 211 {
 212         unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
 213         unsigned off = pixlen * var->xoffset
 214                       + info->fix.line_length * var->yoffset;
 215         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 216
 217         writel((1 << 31)
 218              | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
 219              | (off >> 2), fbi->regbase + 0x20);
 220         return 0;
 221 }
 222
 223 /*
 224  * vt8500lcd_blank():
 225  *      Blank the display by setting all palette values to zero.  Note,
 226  *      True Color modes do not really use the palette, so this will not
 227  *      blank the display in all modes.
 228  */
 229 static int vt8500lcd_blank(int blank, struct fb_info *info)
 230 {
 231         int i;
 232
 233         switch (blank) {
 234         case FB_BLANK_POWERDOWN:
 235         case FB_BLANK_VSYNC_SUSPEND:
 236         case FB_BLANK_HSYNC_SUSPEND:
 237         case FB_BLANK_NORMAL:
 238                 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
 239                     info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
 240                         for (i = 0; i < 256; i++)
 241                                 vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
 242         case FB_BLANK_UNBLANK:
 243                 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
 244                     info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
 245                         fb_set_cmap(&info->cmap, info);
 246         }
 247         return 0;
 248 }
 249
 250 static struct fb_ops vt8500lcd_ops = {
 251         .owner          = THIS_MODULE,
 252         .fb_set_par     = vt8500lcd_set_par,
 253         .fb_setcolreg   = vt8500lcd_setcolreg,
 254         .fb_fillrect    = wmt_ge_fillrect,
 255         .fb_copyarea    = wmt_ge_copyarea,
 256         .fb_imageblit   = sys_imageblit,
 257         .fb_sync        = wmt_ge_sync,
 258         .fb_ioctl       = vt8500lcd_ioctl,
 259         .fb_pan_display = vt8500lcd_pan_display,
 260         .fb_blank       = vt8500lcd_blank,
 261 };
 262
 263 static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
 264 {
 265         struct vt8500lcd_info *fbi = dev_id;
 266
 267         if (readl(fbi->regbase + 0x38) & (1 << 3))
 268                 wake_up_interruptible(&fbi->wait);
 269
 270         writel(0xffffffff, fbi->regbase + 0x38);
 271         return IRQ_HANDLED;
 272 }
 273
 274 static int vt8500lcd_probe(struct platform_device *pdev)
 275 {
 276         struct vt8500lcd_info *fbi;
 277         struct resource *res;
 278         void *addr;
 279         int irq, ret;
 280
 281         struct fb_videomode     of_mode;
 282         struct device_node      *np;
 283         u32                     bpp;
 284         dma_addr_t fb_mem_phys;
 285         unsigned long fb_mem_len;
 286         void *fb_mem_virt;
 287
 288         ret = -ENOMEM;
 289         fbi = NULL;
 290
 291         fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info)
 292                         + sizeof(u32) * 16, GFP_KERNEL);
 293         if (!fbi) {
 294                 dev_err(&pdev->dev, "Failed to initialize framebuffer device\n");
 295                 ret = -ENOMEM;
 296                 goto failed;
 297         }
 298
 299         strcpy(fbi->fb.fix.id, "VT8500 LCD");
 300
 301         fbi->fb.fix.type        = FB_TYPE_PACKED_PIXELS;
 302         fbi->fb.fix.xpanstep    = 0;
 303         fbi->fb.fix.ypanstep    = 1;
 304         fbi->fb.fix.ywrapstep   = 0;
 305         fbi->fb.fix.accel       = FB_ACCEL_NONE;
 306
 307         fbi->fb.var.nonstd      = 0;
 308         fbi->fb.var.activate    = FB_ACTIVATE_NOW;
 309         fbi->fb.var.height      = -1;
 310         fbi->fb.var.width       = -1;
 311         fbi->fb.var.vmode       = FB_VMODE_NONINTERLACED;
 312
 313         fbi->fb.fbops           = &vt8500lcd_ops;
 314         fbi->fb.flags           = FBINFO_DEFAULT
 315                                 | FBINFO_HWACCEL_COPYAREA
 316                                 | FBINFO_HWACCEL_FILLRECT
 317                                 | FBINFO_HWACCEL_YPAN
 318                                 | FBINFO_VIRTFB
 319                                 | FBINFO_PARTIAL_PAN_OK;
 320         fbi->fb.node            = -1;
 321
 322         addr = fbi;
 323         addr = addr + sizeof(struct vt8500lcd_info);
 324         fbi->fb.pseudo_palette  = addr;
 325
 326         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 327         if (res == NULL) {
 328                 dev_err(&pdev->dev, "no I/O memory resource defined\n");
 329                 ret = -ENODEV;
 330                 goto failed_fbi;
 331         }
 332
 333         res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
 334         if (res == NULL) {
 335                 dev_err(&pdev->dev, "failed to request I/O memory\n");
 336                 ret = -EBUSY;
 337                 goto failed_fbi;
 338         }
 339
 340         fbi->regbase = ioremap(res->start, resource_size(res));
 341         if (fbi->regbase == NULL) {
 342                 dev_err(&pdev->dev, "failed to map I/O memory\n");
 343                 ret = -EBUSY;
 344                 goto failed_free_res;
 345         }
 346
 347         np = of_parse_phandle(pdev->dev.of_node, "default-mode", 0);
 348         if (!np) {
 349                 pr_err("%s: No display description in Device Tree\n", __func__);
 350                 ret = -EINVAL;
 351                 goto failed_free_res;
 352         }
 353
 354         /*
 355          * This code is copied from Sascha Hauer's of_videomode helper
 356          * and can be replaced with a call to the helper once mainlined
 357          */
 358         ret = 0;
 359         ret |= of_property_read_u32(np, "hactive", &of_mode.xres);
 360         ret |= of_property_read_u32(np, "vactive", &of_mode.yres);
 361         ret |= of_property_read_u32(np, "hback-porch", &of_mode.left_margin);
 362         ret |= of_property_read_u32(np, "hfront-porch", &of_mode.right_margin);
 363         ret |= of_property_read_u32(np, "hsync-len", &of_mode.hsync_len);
 364         ret |= of_property_read_u32(np, "vback-porch", &of_mode.upper_margin);
 365         ret |= of_property_read_u32(np, "vfront-porch", &of_mode.lower_margin);
 366         ret |= of_property_read_u32(np, "vsync-len", &of_mode.vsync_len);
 367         ret |= of_property_read_u32(np, "bpp", &bpp);
 368         if (ret) {
 369                 pr_err("%s: Unable to read display properties\n", __func__);
 370                 goto failed_free_res;
 371         }
 372         of_mode.vmode = FB_VMODE_NONINTERLACED;
 373
 374         /* try allocating the framebuffer */
 375         fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8);
 376         fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
 377                                 GFP_KERNEL);
 378         if (!fb_mem_virt) {
 379                 pr_err("%s: Failed to allocate framebuffer\n", __func__);
 380                 return -ENOMEM;
 381         };
 382
 383         fbi->fb.fix.smem_start  = fb_mem_phys;
 384         fbi->fb.fix.smem_len    = fb_mem_len;
 385         fbi->fb.screen_base     = fb_mem_virt;
 386
 387         fbi->palette_size       = PAGE_ALIGN(512);
 388         fbi->palette_cpu        = dma_alloc_coherent(&pdev->dev,
 389                                                      fbi->palette_size,
 390                                                      &fbi->palette_phys,
 391                                                      GFP_KERNEL);
 392         if (fbi->palette_cpu == NULL) {
 393                 dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
 394                 ret = -ENOMEM;
 395                 goto failed_free_io;
 396         }
 397
 398         irq = platform_get_irq(pdev, 0);
 399         if (irq < 0) {
 400                 dev_err(&pdev->dev, "no IRQ defined\n");
 401                 ret = -ENODEV;
 402                 goto failed_free_palette;
 403         }
 404
 405         ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
 406         if (ret) {
 407                 dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
 408                 ret = -EBUSY;
 409                 goto failed_free_palette;
 410         }
 411
 412         init_waitqueue_head(&fbi->wait);
 413
 414         if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
 415                 dev_err(&pdev->dev, "Failed to allocate color map\n");
 416                 ret = -ENOMEM;
 417                 goto failed_free_irq;
 418         }
 419
 420         fb_videomode_to_var(&fbi->fb.var, &of_mode);
 421
 422         fbi->fb.var.xres_virtual        = of_mode.xres;
 423         fbi->fb.var.yres_virtual        = of_mode.yres * 2;
 424         fbi->fb.var.bits_per_pixel      = bpp;
 425
 426         ret = vt8500lcd_set_par(&fbi->fb);
 427         if (ret) {
 428                 dev_err(&pdev->dev, "Failed to set parameters\n");
 429                 goto failed_free_cmap;
 430         }
 431
 432         writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
 433         writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
 434
 435         platform_set_drvdata(pdev, fbi);
 436
 437         ret = register_framebuffer(&fbi->fb);
 438         if (ret < 0) {
 439                 dev_err(&pdev->dev,
 440                         "Failed to register framebuffer device: %d\n", ret);
 441                 goto failed_free_cmap;
 442         }
 443
 444         /*
 445          * Ok, now enable the LCD controller
 446          */
 447         writel(readl(fbi->regbase) | 1, fbi->regbase);
 448
 449         return 0;
 450
 451 failed_free_cmap:
 452         if (fbi->fb.cmap.len)
 453                 fb_dealloc_cmap(&fbi->fb.cmap);
 454 failed_free_irq:
 455         free_irq(irq, fbi);
 456 failed_free_palette:
 457         dma_free_coherent(&pdev->dev, fbi->palette_size,
 458                           fbi->palette_cpu, fbi->palette_phys);
 459 failed_free_io:
 460         iounmap(fbi->regbase);
 461 failed_free_res:
 462         release_mem_region(res->start, resource_size(res));
 463 failed_fbi:
 464         platform_set_drvdata(pdev, NULL);
 465         kfree(fbi);
 466 failed:
 467         return ret;
 468 }
 469
 470 static int vt8500lcd_remove(struct platform_device *pdev)
 471 {
 472         struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
 473         struct resource *res;
 474         int irq;
 475
 476         unregister_framebuffer(&fbi->fb);
 477
 478         writel(0, fbi->regbase);
 479
 480         if (fbi->fb.cmap.len)
 481                 fb_dealloc_cmap(&fbi->fb.cmap);
 482
 483         irq = platform_get_irq(pdev, 0);
 484         free_irq(irq, fbi);
 485
 486         dma_free_coherent(&pdev->dev, fbi->palette_size,
 487                           fbi->palette_cpu, fbi->palette_phys);
 488
 489         iounmap(fbi->regbase);
 490
 491         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 492         release_mem_region(res->start, resource_size(res));
 493
 494         kfree(fbi);
 495
 496         return 0;
 497 }
 498
 499 static const struct of_device_id via_dt_ids[] = {
 500         { .compatible = "via,vt8500-fb", },
 501         {}
 502 };
 503
 504 static struct platform_driver vt8500lcd_driver = {
 505         .probe          = vt8500lcd_probe,
 506         .remove         = vt8500lcd_remove,
 507         .driver         = {
 508                 .owner  = THIS_MODULE,
 509                 .name   = "vt8500-lcd",
 510                 .of_match_table = of_match_ptr(via_dt_ids),
 511         },
 512 };
 513
 514 module_platform_driver(vt8500lcd_driver);
 515
 516 MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
 517 MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
 518 MODULE_LICENSE("GPL v2");
 519 MODULE_DEVICE_TABLE(of, via_dt_ids);