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