drivers/video/fbdev/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         }
 119
 120         control0 = readl(fbi->regbase) & ~0xf;
 121         writel(0, fbi->regbase);
 122         while (readl(fbi->regbase + 0x38) & 0x10)
 123                 /* wait */;
 124         writel((((info->var.hsync_len - 1) & 0x3f) << 26)
 125                 | ((info->var.left_margin & 0xff) << 18)
 126                 | (((info->var.xres - 1) & 0x3ff) << 8)
 127                 | (info->var.right_margin & 0xff), fbi->regbase + 0x4);
 128         writel((((info->var.vsync_len - 1) & 0x3f) << 26)
 129                 | ((info->var.upper_margin & 0xff) << 18)
 130                 | (((info->var.yres - 1) & 0x3ff) << 8)
 131                 | (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
 132         writel((((info->var.yres - 1) & 0x400) << 2)
 133                 | ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
 134         writel(0x80000000, fbi->regbase + 0x20);
 135         writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
 136
 137         return 0;
 138 }
 139
 140 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
 141 {
 142         chan &= 0xffff;
 143         chan >>= 16 - bf->length;
 144         return chan << bf->offset;
 145 }
 146
 147 static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
 148                            unsigned blue, unsigned transp,
 149                            struct fb_info *info) {
 150         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 151         int ret = 1;
 152         unsigned int val;
 153         if (regno >= 256)
 154                 return -EINVAL;
 155
 156         if (info->var.grayscale)
 157                 red = green = blue =
 158                         (19595 * red + 38470 * green + 7471 * blue) >> 16;
 159
 160         switch (fbi->fb.fix.visual) {
 161         case FB_VISUAL_TRUECOLOR:
 162                 if (regno < 16) {
 163                         u32 *pal = fbi->fb.pseudo_palette;
 164
 165                         val  = chan_to_field(red, &fbi->fb.var.red);
 166                         val |= chan_to_field(green, &fbi->fb.var.green);
 167                         val |= chan_to_field(blue, &fbi->fb.var.blue);
 168
 169                         pal[regno] = val;
 170                         ret = 0;
 171                 }
 172                 break;
 173
 174         case FB_VISUAL_STATIC_PSEUDOCOLOR:
 175         case FB_VISUAL_PSEUDOCOLOR:
 176                 writew((red & 0xf800)
 177                       | ((green >> 5) & 0x7e0)
 178                       | ((blue >> 11) & 0x1f),
 179                        fbi->palette_cpu + sizeof(u16) * regno);
 180                 break;
 181         }
 182
 183         return ret;
 184 }
 185
 186 static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
 187                          unsigned long arg)
 188 {
 189         int ret = 0;
 190         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 191
 192         if (cmd == FBIO_WAITFORVSYNC) {
 193                 /* Unmask End of Frame interrupt */
 194                 writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
 195                 ret = wait_event_interruptible_timeout(fbi->wait,
 196                         readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
 197                 /* Mask back to reduce unwanted interrupt traffic */
 198                 writel(0xffffffff, fbi->regbase + 0x3c);
 199                 if (ret < 0)
 200                         return ret;
 201                 if (ret == 0)
 202                         return -ETIMEDOUT;
 203         }
 204
 205         return ret;
 206 }
 207
 208 static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
 209                                 struct fb_info *info)
 210 {
 211         unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
 212         unsigned off = pixlen * var->xoffset
 213                       + info->fix.line_length * var->yoffset;
 214         struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
 215
 216         writel((1 << 31)
 217              | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
 218              | (off >> 2), fbi->regbase + 0x20);
 219         return 0;
 220 }
 221
 222 /*
 223  * vt8500lcd_blank():
 224  *      Blank the display by setting all palette values to zero.  Note,
 225  *      True Color modes do not really use the palette, so this will not
 226  *      blank the display in all modes.
 227  */
 228 static int vt8500lcd_blank(int blank, struct fb_info *info)
 229 {
 230         int i;
 231
 232         switch (blank) {
 233         case FB_BLANK_POWERDOWN:
 234         case FB_BLANK_VSYNC_SUSPEND:
 235         case FB_BLANK_HSYNC_SUSPEND:
 236         case FB_BLANK_NORMAL:
 237                 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
 238                     info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
 239                         for (i = 0; i < 256; i++)
 240                                 vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
 241         case FB_BLANK_UNBLANK:
 242                 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
 243                     info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
 244                         fb_set_cmap(&info->cmap, info);
 245         }
 246         return 0;
 247 }
 248
 249 static struct fb_ops vt8500lcd_ops = {
 250         .owner          = THIS_MODULE,
 251         .fb_set_par     = vt8500lcd_set_par,
 252         .fb_setcolreg   = vt8500lcd_setcolreg,
 253         .fb_fillrect    = wmt_ge_fillrect,
 254         .fb_copyarea    = wmt_ge_copyarea,
 255         .fb_imageblit   = sys_imageblit,
 256         .fb_sync        = wmt_ge_sync,
 257         .fb_ioctl       = vt8500lcd_ioctl,
 258         .fb_pan_display = vt8500lcd_pan_display,
 259         .fb_blank       = vt8500lcd_blank,
 260 };
 261
 262 static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
 263 {
 264         struct vt8500lcd_info *fbi = dev_id;
 265
 266         if (readl(fbi->regbase + 0x38) & (1 << 3))
 267                 wake_up_interruptible(&fbi->wait);
 268
 269         writel(0xffffffff, fbi->regbase + 0x38);
 270         return IRQ_HANDLED;
 271 }
 272
 273 static int vt8500lcd_probe(struct platform_device *pdev)
 274 {
 275         struct vt8500lcd_info *fbi;
 276         struct resource *res;
 277         struct display_timings *disp_timing;
 278         void *addr;
 279         int irq, ret;
 280
 281         struct fb_videomode     of_mode;
 282         u32                     bpp;
 283         dma_addr_t fb_mem_phys;
 284         unsigned long fb_mem_len;
 285         void *fb_mem_virt;
 286
 287         ret = -ENOMEM;
 288         fbi = NULL;
 289
 290         fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info)
 291                         + sizeof(u32) * 16, GFP_KERNEL);
 292         if (!fbi) {
 293                 dev_err(&pdev->dev, "Failed to initialize framebuffer device\n");
 294                 return -ENOMEM;
 295         }
 296
 297         strcpy(fbi->fb.fix.id, "VT8500 LCD");
 298
 299         fbi->fb.fix.type        = FB_TYPE_PACKED_PIXELS;
 300         fbi->fb.fix.xpanstep    = 0;
 301         fbi->fb.fix.ypanstep    = 1;
 302         fbi->fb.fix.ywrapstep   = 0;
 303         fbi->fb.fix.accel       = FB_ACCEL_NONE;
 304
 305         fbi->fb.var.nonstd      = 0;
 306         fbi->fb.var.activate    = FB_ACTIVATE_NOW;
 307         fbi->fb.var.height      = -1;
 308         fbi->fb.var.width       = -1;
 309         fbi->fb.var.vmode       = FB_VMODE_NONINTERLACED;
 310
 311         fbi->fb.fbops           = &vt8500lcd_ops;
 312         fbi->fb.flags           = FBINFO_DEFAULT
 313                                 | FBINFO_HWACCEL_COPYAREA
 314                                 | FBINFO_HWACCEL_FILLRECT
 315                                 | FBINFO_HWACCEL_YPAN
 316                                 | FBINFO_VIRTFB
 317                                 | FBINFO_PARTIAL_PAN_OK;
 318         fbi->fb.node            = -1;
 319
 320         addr = fbi;
 321         addr = addr + sizeof(struct vt8500lcd_info);
 322         fbi->fb.pseudo_palette  = addr;
 323
 324         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 325         if (res == NULL) {
 326                 dev_err(&pdev->dev, "no I/O memory resource defined\n");
 327                 return -ENODEV;
 328         }
 329
 330         res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
 331         if (res == NULL) {
 332                 dev_err(&pdev->dev, "failed to request I/O memory\n");
 333                 return -EBUSY;
 334         }
 335
 336         fbi->regbase = ioremap(res->start, resource_size(res));
 337         if (fbi->regbase == NULL) {
 338                 dev_err(&pdev->dev, "failed to map I/O memory\n");
 339                 ret = -EBUSY;
 340                 goto failed_free_res;
 341         }
 342
 343         disp_timing = of_get_display_timings(pdev->dev.of_node);
 344         if (!disp_timing) {
 345                 ret = -EINVAL;
 346                 goto failed_free_io;
 347         }
 348
 349         ret = of_get_fb_videomode(pdev->dev.of_node, &of_mode,
 350                                                         OF_USE_NATIVE_MODE);
 351         if (ret)
 352                 goto failed_free_io;
 353
 354         ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
 355         if (ret)
 356                 goto failed_free_io;
 357
 358         /* try allocating the framebuffer */
 359         fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8);
 360         fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
 361                                 GFP_KERNEL);
 362         if (!fb_mem_virt) {
 363                 pr_err("%s: Failed to allocate framebuffer\n", __func__);
 364                 ret = -ENOMEM;
 365                 goto failed_free_io;
 366         }
 367
 368         fbi->fb.fix.smem_start  = fb_mem_phys;
 369         fbi->fb.fix.smem_len    = fb_mem_len;
 370         fbi->fb.screen_base     = fb_mem_virt;
 371
 372         fbi->palette_size       = PAGE_ALIGN(512);
 373         fbi->palette_cpu        = dma_alloc_coherent(&pdev->dev,
 374                                                      fbi->palette_size,
 375                                                      &fbi->palette_phys,
 376                                                      GFP_KERNEL);
 377         if (fbi->palette_cpu == NULL) {
 378                 dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
 379                 ret = -ENOMEM;
 380                 goto failed_free_io;
 381         }
 382
 383         irq = platform_get_irq(pdev, 0);
 384         if (irq < 0) {
 385                 dev_err(&pdev->dev, "no IRQ defined\n");
 386                 ret = -ENODEV;
 387                 goto failed_free_palette;
 388         }
 389
 390         ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
 391         if (ret) {
 392                 dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
 393                 ret = -EBUSY;
 394                 goto failed_free_palette;
 395         }
 396
 397         init_waitqueue_head(&fbi->wait);
 398
 399         if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
 400                 dev_err(&pdev->dev, "Failed to allocate color map\n");
 401                 ret = -ENOMEM;
 402                 goto failed_free_irq;
 403         }
 404
 405         fb_videomode_to_var(&fbi->fb.var, &of_mode);
 406
 407         fbi->fb.var.xres_virtual        = of_mode.xres;
 408         fbi->fb.var.yres_virtual        = of_mode.yres * 2;
 409         fbi->fb.var.bits_per_pixel      = bpp;
 410
 411         ret = vt8500lcd_set_par(&fbi->fb);
 412         if (ret) {
 413                 dev_err(&pdev->dev, "Failed to set parameters\n");
 414                 goto failed_free_cmap;
 415         }
 416
 417         writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
 418         writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
 419
 420         platform_set_drvdata(pdev, fbi);
 421
 422         ret = register_framebuffer(&fbi->fb);
 423         if (ret < 0) {
 424                 dev_err(&pdev->dev,
 425                         "Failed to register framebuffer device: %d\n", ret);
 426                 goto failed_free_cmap;
 427         }
 428
 429         /*
 430          * Ok, now enable the LCD controller
 431          */
 432         writel(readl(fbi->regbase) | 1, fbi->regbase);
 433
 434         return 0;
 435
 436 failed_free_cmap:
 437         if (fbi->fb.cmap.len)
 438                 fb_dealloc_cmap(&fbi->fb.cmap);
 439 failed_free_irq:
 440         free_irq(irq, fbi);
 441 failed_free_palette:
 442         dma_free_coherent(&pdev->dev, fbi->palette_size,
 443                           fbi->palette_cpu, fbi->palette_phys);
 444 failed_free_io:
 445         iounmap(fbi->regbase);
 446 failed_free_res:
 447         release_mem_region(res->start, resource_size(res));
 448         return ret;
 449 }
 450
 451 static int vt8500lcd_remove(struct platform_device *pdev)
 452 {
 453         struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
 454         struct resource *res;
 455         int irq;
 456
 457         unregister_framebuffer(&fbi->fb);
 458
 459         writel(0, fbi->regbase);
 460
 461         if (fbi->fb.cmap.len)
 462                 fb_dealloc_cmap(&fbi->fb.cmap);
 463
 464         irq = platform_get_irq(pdev, 0);
 465         free_irq(irq, fbi);
 466
 467         dma_free_coherent(&pdev->dev, fbi->palette_size,
 468                           fbi->palette_cpu, fbi->palette_phys);
 469
 470         iounmap(fbi->regbase);
 471
 472         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 473         release_mem_region(res->start, resource_size(res));
 474
 475         return 0;
 476 }
 477
 478 static const struct of_device_id via_dt_ids[] = {
 479         { .compatible = "via,vt8500-fb", },
 480         {}
 481 };
 482
 483 static struct platform_driver vt8500lcd_driver = {
 484         .probe          = vt8500lcd_probe,
 485         .remove         = vt8500lcd_remove,
 486         .driver         = {
 487                 .name   = "vt8500-lcd",
 488                 .of_match_table = of_match_ptr(via_dt_ids),
 489         },
 490 };
 491
 492 module_platform_driver(vt8500lcd_driver);
 493
 494 MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
 495 MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
 496 MODULE_LICENSE("GPL v2");
 497 MODULE_DEVICE_TABLE(of, via_dt_ids);