drivers/video/fbdev/ep93xx-fb.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * linux/drivers/video/ep93xx-fb.c
   4  *
   5  * Framebuffer support for the EP93xx series.
   6  *
   7  * Copyright (C) 2007 Bluewater Systems Ltd
   8  * Author: Ryan Mallon
   9  *
  10  * Copyright (c) 2009 H Hartley Sweeten <hsweeten@visionengravers.com>
  11  *
  12  * Based on the Cirrus Logic ep93xxfb driver, and various other ep93xxfb
  13  * drivers.
  14  */
  15
  16 #include <linux/platform_device.h>
  17 #include <linux/module.h>
  18 #include <linux/dma-mapping.h>
  19 #include <linux/slab.h>
  20 #include <linux/clk.h>
  21 #include <linux/fb.h>
  22 #include <linux/io.h>
  23
  24 #include <linux/platform_data/video-ep93xx.h>
  25
  26 /* Vertical Frame Timing Registers */
  27 #define EP93XXFB_VLINES_TOTAL                   0x0000  /* SW locked */
  28 #define EP93XXFB_VSYNC                          0x0004  /* SW locked */
  29 #define EP93XXFB_VACTIVE                        0x0008  /* SW locked */
  30 #define EP93XXFB_VBLANK                         0x0228  /* SW locked */
  31 #define EP93XXFB_VCLK                           0x000c  /* SW locked */
  32
  33 /* Horizontal Frame Timing Registers */
  34 #define EP93XXFB_HCLKS_TOTAL                    0x0010  /* SW locked */
  35 #define EP93XXFB_HSYNC                          0x0014  /* SW locked */
  36 #define EP93XXFB_HACTIVE                        0x0018  /* SW locked */
  37 #define EP93XXFB_HBLANK                         0x022c  /* SW locked */
  38 #define EP93XXFB_HCLK                           0x001c  /* SW locked */
  39
  40 /* Frame Buffer Memory Configuration Registers */
  41 #define EP93XXFB_SCREEN_PAGE                    0x0028
  42 #define EP93XXFB_SCREEN_HPAGE                   0x002c
  43 #define EP93XXFB_SCREEN_LINES                   0x0030
  44 #define EP93XXFB_LINE_LENGTH                    0x0034
  45 #define EP93XXFB_VLINE_STEP                     0x0038
  46 #define EP93XXFB_LINE_CARRY                     0x003c  /* SW locked */
  47 #define EP93XXFB_EOL_OFFSET                     0x0230
  48
  49 /* Other Video Registers */
  50 #define EP93XXFB_BRIGHTNESS                     0x0020
  51 #define EP93XXFB_ATTRIBS                        0x0024  /* SW locked */
  52 #define EP93XXFB_SWLOCK                         0x007c  /* SW locked */
  53 #define EP93XXFB_AC_RATE                        0x0214
  54 #define EP93XXFB_FIFO_LEVEL                     0x0234
  55 #define EP93XXFB_PIXELMODE                      0x0054
  56 #define EP93XXFB_PIXELMODE_32BPP                (0x7 << 0)
  57 #define EP93XXFB_PIXELMODE_24BPP                (0x6 << 0)
  58 #define EP93XXFB_PIXELMODE_16BPP                (0x4 << 0)
  59 #define EP93XXFB_PIXELMODE_8BPP                 (0x2 << 0)
  60 #define EP93XXFB_PIXELMODE_SHIFT_1P_24B         (0x0 << 3)
  61 #define EP93XXFB_PIXELMODE_SHIFT_1P_18B         (0x1 << 3)
  62 #define EP93XXFB_PIXELMODE_COLOR_LUT            (0x0 << 10)
  63 #define EP93XXFB_PIXELMODE_COLOR_888            (0x4 << 10)
  64 #define EP93XXFB_PIXELMODE_COLOR_555            (0x5 << 10)
  65 #define EP93XXFB_PARL_IF_OUT                    0x0058
  66 #define EP93XXFB_PARL_IF_IN                     0x005c
  67
  68 /* Blink Control Registers */
  69 #define EP93XXFB_BLINK_RATE                     0x0040
  70 #define EP93XXFB_BLINK_MASK                     0x0044
  71 #define EP93XXFB_BLINK_PATTRN                   0x0048
  72 #define EP93XXFB_PATTRN_MASK                    0x004c
  73 #define EP93XXFB_BKGRND_OFFSET                  0x0050
  74
  75 /* Hardware Cursor Registers */
  76 #define EP93XXFB_CURSOR_ADR_START               0x0060
  77 #define EP93XXFB_CURSOR_ADR_RESET               0x0064
  78 #define EP93XXFB_CURSOR_SIZE                    0x0068
  79 #define EP93XXFB_CURSOR_COLOR1                  0x006c
  80 #define EP93XXFB_CURSOR_COLOR2                  0x0070
  81 #define EP93XXFB_CURSOR_BLINK_COLOR1            0x021c
  82 #define EP93XXFB_CURSOR_BLINK_COLOR2            0x0220
  83 #define EP93XXFB_CURSOR_XY_LOC                  0x0074
  84 #define EP93XXFB_CURSOR_DSCAN_HY_LOC            0x0078
  85 #define EP93XXFB_CURSOR_BLINK_RATE_CTRL         0x0224
  86
  87 /* LUT Registers */
  88 #define EP93XXFB_GRY_SCL_LUTR                   0x0080
  89 #define EP93XXFB_GRY_SCL_LUTG                   0x0280
  90 #define EP93XXFB_GRY_SCL_LUTB                   0x0300
  91 #define EP93XXFB_LUT_SW_CONTROL                 0x0218
  92 #define EP93XXFB_LUT_SW_CONTROL_SWTCH           (1 << 0)
  93 #define EP93XXFB_LUT_SW_CONTROL_SSTAT           (1 << 1)
  94 #define EP93XXFB_COLOR_LUT                      0x0400
  95
  96 /* Video Signature Registers */
  97 #define EP93XXFB_VID_SIG_RSLT_VAL               0x0200
  98 #define EP93XXFB_VID_SIG_CTRL                   0x0204
  99 #define EP93XXFB_VSIG                           0x0208
 100 #define EP93XXFB_HSIG                           0x020c
 101 #define EP93XXFB_SIG_CLR_STR                    0x0210
 102
 103 /* Minimum / Maximum resolutions supported */
 104 #define EP93XXFB_MIN_XRES                       64
 105 #define EP93XXFB_MIN_YRES                       64
 106 #define EP93XXFB_MAX_XRES                       1024
 107 #define EP93XXFB_MAX_YRES                       768
 108
 109 struct ep93xx_fbi {
 110         struct ep93xxfb_mach_info       *mach_info;
 111         struct clk                      *clk;
 112         struct resource                 *res;
 113         void __iomem                    *mmio_base;
 114         unsigned int                    pseudo_palette[256];
 115 };
 116
 117 static int check_screenpage_bug = 1;
 118 module_param(check_screenpage_bug, int, 0644);
 119 MODULE_PARM_DESC(check_screenpage_bug,
 120                  "Check for bit 27 screen page bug. Default = 1");
 121
 122 static inline unsigned int ep93xxfb_readl(struct ep93xx_fbi *fbi,
 123                                           unsigned int off)
 124 {
 125         return __raw_readl(fbi->mmio_base + off);
 126 }
 127
 128 static inline void ep93xxfb_writel(struct ep93xx_fbi *fbi,
 129                                    unsigned int val, unsigned int off)
 130 {
 131         __raw_writel(val, fbi->mmio_base + off);
 132 }
 133
 134 /*
 135  * Write to one of the locked raster registers.
 136  */
 137 static inline void ep93xxfb_out_locked(struct ep93xx_fbi *fbi,
 138                                        unsigned int val, unsigned int reg)
 139 {
 140         /*
 141          * We don't need a lock or delay here since the raster register
 142          * block will remain unlocked until the next access.
 143          */
 144         ep93xxfb_writel(fbi, 0xaa, EP93XXFB_SWLOCK);
 145         ep93xxfb_writel(fbi, val, reg);
 146 }
 147
 148 static void ep93xxfb_set_video_attribs(struct fb_info *info)
 149 {
 150         struct ep93xx_fbi *fbi = info->par;
 151         unsigned int attribs;
 152
 153         attribs = EP93XXFB_ENABLE;
 154         attribs |= fbi->mach_info->flags;
 155         ep93xxfb_out_locked(fbi, attribs, EP93XXFB_ATTRIBS);
 156 }
 157
 158 static int ep93xxfb_set_pixelmode(struct fb_info *info)
 159 {
 160         struct ep93xx_fbi *fbi = info->par;
 161         unsigned int val;
 162
 163         info->var.transp.offset = 0;
 164         info->var.transp.length = 0;
 165
 166         switch (info->var.bits_per_pixel) {
 167         case 8:
 168                 val = EP93XXFB_PIXELMODE_8BPP | EP93XXFB_PIXELMODE_COLOR_LUT |
 169                         EP93XXFB_PIXELMODE_SHIFT_1P_18B;
 170
 171                 info->var.red.offset    = 0;
 172                 info->var.red.length    = 8;
 173                 info->var.green.offset  = 0;
 174                 info->var.green.length  = 8;
 175                 info->var.blue.offset   = 0;
 176                 info->var.blue.length   = 8;
 177                 info->fix.visual        = FB_VISUAL_PSEUDOCOLOR;
 178                 break;
 179
 180         case 16:
 181                 val = EP93XXFB_PIXELMODE_16BPP | EP93XXFB_PIXELMODE_COLOR_555 |
 182                         EP93XXFB_PIXELMODE_SHIFT_1P_18B;
 183
 184                 info->var.red.offset    = 11;
 185                 info->var.red.length    = 5;
 186                 info->var.green.offset  = 5;
 187                 info->var.green.length  = 6;
 188                 info->var.blue.offset   = 0;
 189                 info->var.blue.length   = 5;
 190                 info->fix.visual        = FB_VISUAL_TRUECOLOR;
 191                 break;
 192
 193         case 24:
 194                 val = EP93XXFB_PIXELMODE_24BPP | EP93XXFB_PIXELMODE_COLOR_888 |
 195                         EP93XXFB_PIXELMODE_SHIFT_1P_24B;
 196
 197                 info->var.red.offset    = 16;
 198                 info->var.red.length    = 8;
 199                 info->var.green.offset  = 8;
 200                 info->var.green.length  = 8;
 201                 info->var.blue.offset   = 0;
 202                 info->var.blue.length   = 8;
 203                 info->fix.visual        = FB_VISUAL_TRUECOLOR;
 204                 break;
 205
 206         case 32:
 207                 val = EP93XXFB_PIXELMODE_32BPP | EP93XXFB_PIXELMODE_COLOR_888 |
 208                         EP93XXFB_PIXELMODE_SHIFT_1P_24B;
 209
 210                 info->var.red.offset    = 16;
 211                 info->var.red.length    = 8;
 212                 info->var.green.offset  = 8;
 213                 info->var.green.length  = 8;
 214                 info->var.blue.offset   = 0;
 215                 info->var.blue.length   = 8;
 216                 info->fix.visual        = FB_VISUAL_TRUECOLOR;
 217                 break;
 218
 219         default:
 220                 return -EINVAL;
 221         }
 222
 223         ep93xxfb_writel(fbi, val, EP93XXFB_PIXELMODE);
 224         return 0;
 225 }
 226
 227 static void ep93xxfb_set_timing(struct fb_info *info)
 228 {
 229         struct ep93xx_fbi *fbi = info->par;
 230         unsigned int vlines_total, hclks_total, start, stop;
 231
 232         vlines_total = info->var.yres + info->var.upper_margin +
 233                 info->var.lower_margin + info->var.vsync_len - 1;
 234
 235         hclks_total = info->var.xres + info->var.left_margin +
 236                 info->var.right_margin + info->var.hsync_len - 1;
 237
 238         ep93xxfb_out_locked(fbi, vlines_total, EP93XXFB_VLINES_TOTAL);
 239         ep93xxfb_out_locked(fbi, hclks_total, EP93XXFB_HCLKS_TOTAL);
 240
 241         start = vlines_total;
 242         stop = vlines_total - info->var.vsync_len;
 243         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_VSYNC);
 244
 245         start = vlines_total - info->var.vsync_len - info->var.upper_margin;
 246         stop = info->var.lower_margin - 1;
 247         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_VBLANK);
 248         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_VACTIVE);
 249
 250         start = vlines_total;
 251         stop = vlines_total + 1;
 252         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_VCLK);
 253
 254         start = hclks_total;
 255         stop = hclks_total - info->var.hsync_len;
 256         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_HSYNC);
 257
 258         start = hclks_total - info->var.hsync_len - info->var.left_margin;
 259         stop = info->var.right_margin - 1;
 260         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_HBLANK);
 261         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_HACTIVE);
 262
 263         start = hclks_total;
 264         stop = hclks_total;
 265         ep93xxfb_out_locked(fbi, start | (stop << 16), EP93XXFB_HCLK);
 266
 267         ep93xxfb_out_locked(fbi, 0x0, EP93XXFB_LINE_CARRY);
 268 }
 269
 270 static int ep93xxfb_set_par(struct fb_info *info)
 271 {
 272         struct ep93xx_fbi *fbi = info->par;
 273
 274         clk_set_rate(fbi->clk, 1000 * PICOS2KHZ(info->var.pixclock));
 275
 276         ep93xxfb_set_timing(info);
 277
 278         info->fix.line_length = info->var.xres_virtual *
 279                 info->var.bits_per_pixel / 8;
 280
 281         ep93xxfb_writel(fbi, info->fix.smem_start, EP93XXFB_SCREEN_PAGE);
 282         ep93xxfb_writel(fbi, info->var.yres - 1, EP93XXFB_SCREEN_LINES);
 283         ep93xxfb_writel(fbi, ((info->var.xres * info->var.bits_per_pixel)
 284                               / 32) - 1, EP93XXFB_LINE_LENGTH);
 285         ep93xxfb_writel(fbi, info->fix.line_length / 4, EP93XXFB_VLINE_STEP);
 286         ep93xxfb_set_video_attribs(info);
 287         return 0;
 288 }
 289
 290 static int ep93xxfb_check_var(struct fb_var_screeninfo *var,
 291                               struct fb_info *info)
 292 {
 293         int err;
 294
 295         err = ep93xxfb_set_pixelmode(info);
 296         if (err)
 297                 return err;
 298
 299         var->xres = max_t(unsigned int, var->xres, EP93XXFB_MIN_XRES);
 300         var->xres = min_t(unsigned int, var->xres, EP93XXFB_MAX_XRES);
 301         var->xres_virtual = max(var->xres_virtual, var->xres);
 302
 303         var->yres = max_t(unsigned int, var->yres, EP93XXFB_MIN_YRES);
 304         var->yres = min_t(unsigned int, var->yres, EP93XXFB_MAX_YRES);
 305         var->yres_virtual = max(var->yres_virtual, var->yres);
 306
 307         return 0;
 308 }
 309
 310 static int ep93xxfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 311 {
 312         unsigned int offset = vma->vm_pgoff << PAGE_SHIFT;
 313
 314         if (offset < info->fix.smem_len) {
 315                 return dma_mmap_wc(info->device, vma, info->screen_base,
 316                                    info->fix.smem_start, info->fix.smem_len);
 317         }
 318
 319         return -EINVAL;
 320 }
 321
 322 static int ep93xxfb_blank(int blank_mode, struct fb_info *info)
 323 {
 324         struct ep93xx_fbi *fbi = info->par;
 325         unsigned int attribs = ep93xxfb_readl(fbi, EP93XXFB_ATTRIBS);
 326
 327         if (blank_mode) {
 328                 if (fbi->mach_info->blank)
 329                         fbi->mach_info->blank(blank_mode, info);
 330                 ep93xxfb_out_locked(fbi, attribs & ~EP93XXFB_ENABLE,
 331                                     EP93XXFB_ATTRIBS);
 332                 clk_disable(fbi->clk);
 333         } else {
 334                 clk_enable(fbi->clk);
 335                 ep93xxfb_out_locked(fbi, attribs | EP93XXFB_ENABLE,
 336                                     EP93XXFB_ATTRIBS);
 337                 if (fbi->mach_info->blank)
 338                         fbi->mach_info->blank(blank_mode, info);
 339         }
 340
 341         return 0;
 342 }
 343
 344 static inline int ep93xxfb_convert_color(int val, int width)
 345 {
 346         return ((val << width) + 0x7fff - val) >> 16;
 347 }
 348
 349 static int ep93xxfb_setcolreg(unsigned int regno, unsigned int red,
 350                               unsigned int green, unsigned int blue,
 351                               unsigned int transp, struct fb_info *info)
 352 {
 353         struct ep93xx_fbi *fbi = info->par;
 354         unsigned int *pal = info->pseudo_palette;
 355         unsigned int ctrl, i, rgb, lut_current, lut_stat;
 356
 357         switch (info->fix.visual) {
 358         case FB_VISUAL_PSEUDOCOLOR:
 359                 if (regno > 255)
 360                         return 1;
 361                 rgb = ((red & 0xff00) << 8) | (green & 0xff00) |
 362                         ((blue & 0xff00) >> 8);
 363
 364                 pal[regno] = rgb;
 365                 ep93xxfb_writel(fbi, rgb, (EP93XXFB_COLOR_LUT + (regno << 2)));
 366                 ctrl = ep93xxfb_readl(fbi, EP93XXFB_LUT_SW_CONTROL);
 367                 lut_stat = !!(ctrl & EP93XXFB_LUT_SW_CONTROL_SSTAT);
 368                 lut_current = !!(ctrl & EP93XXFB_LUT_SW_CONTROL_SWTCH);
 369
 370                 if (lut_stat == lut_current) {
 371                         for (i = 0; i < 256; i++) {
 372                                 ep93xxfb_writel(fbi, pal[i],
 373                                         EP93XXFB_COLOR_LUT + (i << 2));
 374                         }
 375
 376                         ep93xxfb_writel(fbi,
 377                                         ctrl ^ EP93XXFB_LUT_SW_CONTROL_SWTCH,
 378                                         EP93XXFB_LUT_SW_CONTROL);
 379                 }
 380                 break;
 381
 382         case FB_VISUAL_TRUECOLOR:
 383                 if (regno > 16)
 384                         return 1;
 385
 386                 red = ep93xxfb_convert_color(red, info->var.red.length);
 387                 green = ep93xxfb_convert_color(green, info->var.green.length);
 388                 blue = ep93xxfb_convert_color(blue, info->var.blue.length);
 389                 transp = ep93xxfb_convert_color(transp,
 390                                                 info->var.transp.length);
 391
 392                 pal[regno] = (red << info->var.red.offset) |
 393                         (green << info->var.green.offset) |
 394                         (blue << info->var.blue.offset) |
 395                         (transp << info->var.transp.offset);
 396                 break;
 397
 398         default:
 399                 return 1;
 400         }
 401
 402         return 0;
 403 }
 404
 405 static const struct fb_ops ep93xxfb_ops = {
 406         .owner          = THIS_MODULE,
 407         __FB_DEFAULT_IOMEM_OPS_RDWR,
 408         .fb_check_var   = ep93xxfb_check_var,
 409         .fb_set_par     = ep93xxfb_set_par,
 410         .fb_blank       = ep93xxfb_blank,
 411         __FB_DEFAULT_IOMEM_OPS_DRAW,
 412         .fb_setcolreg   = ep93xxfb_setcolreg,
 413         .fb_mmap        = ep93xxfb_mmap,
 414 };
 415
 416 static int ep93xxfb_alloc_videomem(struct fb_info *info)
 417 {
 418         char __iomem *virt_addr;
 419         dma_addr_t phys_addr;
 420         unsigned int fb_size;
 421
 422         /* Maximum 16bpp -> used memory is maximum x*y*2 bytes */
 423         fb_size = EP93XXFB_MAX_XRES * EP93XXFB_MAX_YRES * 2;
 424
 425         virt_addr = dma_alloc_wc(info->device, fb_size, &phys_addr, GFP_KERNEL);
 426         if (!virt_addr)
 427                 return -ENOMEM;
 428
 429         /*
 430          * There is a bug in the ep93xx framebuffer which causes problems
 431          * if bit 27 of the physical address is set.
 432          * See: https://marc.info/?l=linux-arm-kernel&m=110061245502000&w=2
 433          * There does not seem to be any official errata for this, but I
 434          * have confirmed the problem exists on my hardware (ep9315) at
 435          * least.
 436          */
 437         if (check_screenpage_bug && phys_addr & (1 << 27)) {
 438                 fb_err(info, "ep93xx framebuffer bug. phys addr (0x%x) "
 439                        "has bit 27 set: cannot init framebuffer\n",
 440                        phys_addr);
 441
 442                 dma_free_coherent(info->device, fb_size, virt_addr, phys_addr);
 443                 return -ENOMEM;
 444         }
 445
 446         info->fix.smem_start = phys_addr;
 447         info->fix.smem_len = fb_size;
 448         info->screen_base = virt_addr;
 449
 450         return 0;
 451 }
 452
 453 static void ep93xxfb_dealloc_videomem(struct fb_info *info)
 454 {
 455         if (info->screen_base)
 456                 dma_free_coherent(info->device, info->fix.smem_len,
 457                                   info->screen_base, info->fix.smem_start);
 458 }
 459
 460 static int ep93xxfb_probe(struct platform_device *pdev)
 461 {
 462         struct ep93xxfb_mach_info *mach_info = dev_get_platdata(&pdev->dev);
 463         struct fb_info *info;
 464         struct ep93xx_fbi *fbi;
 465         struct resource *res;
 466         char *video_mode;
 467         int err;
 468
 469         if (!mach_info)
 470                 return -EINVAL;
 471
 472         info = framebuffer_alloc(sizeof(struct ep93xx_fbi), &pdev->dev);
 473         if (!info)
 474                 return -ENOMEM;
 475
 476         platform_set_drvdata(pdev, info);
 477         fbi = info->par;
 478         fbi->mach_info = mach_info;
 479
 480         err = fb_alloc_cmap(&info->cmap, 256, 0);
 481         if (err)
 482                 goto failed_cmap;
 483
 484         err = ep93xxfb_alloc_videomem(info);
 485         if (err)
 486                 goto failed_videomem;
 487
 488         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 489         if (!res) {
 490                 err = -ENXIO;
 491                 goto failed_resource;
 492         }
 493
 494         /*
 495          * FIXME - We don't do a request_mem_region here because we are
 496          * sharing the register space with the backlight driver (see
 497          * drivers/video/backlight/ep93xx_bl.c) and doing so will cause
 498          * the second loaded driver to return -EBUSY.
 499          *
 500          * NOTE: No locking is required; the backlight does not touch
 501          * any of the framebuffer registers.
 502          */
 503         fbi->res = res;
 504         fbi->mmio_base = devm_ioremap(&pdev->dev, res->start,
 505                                       resource_size(res));
 506         if (!fbi->mmio_base) {
 507                 err = -ENXIO;
 508                 goto failed_resource;
 509         }
 510
 511         strcpy(info->fix.id, pdev->name);
 512         info->fbops             = &ep93xxfb_ops;
 513         info->fix.type          = FB_TYPE_PACKED_PIXELS;
 514         info->fix.accel         = FB_ACCEL_NONE;
 515         info->var.activate      = FB_ACTIVATE_NOW;
 516         info->var.vmode         = FB_VMODE_NONINTERLACED;
 517         info->node              = -1;
 518         info->state             = FBINFO_STATE_RUNNING;
 519         info->pseudo_palette    = &fbi->pseudo_palette;
 520
 521         fb_get_options("ep93xx-fb", &video_mode);
 522         err = fb_find_mode(&info->var, info, video_mode,
 523                            NULL, 0, NULL, 16);
 524         if (err == 0) {
 525                 fb_err(info, "No suitable video mode found\n");
 526                 err = -EINVAL;
 527                 goto failed_resource;
 528         }
 529
 530         if (mach_info->setup) {
 531                 err = mach_info->setup(pdev);
 532                 if (err)
 533                         goto failed_resource;
 534         }
 535
 536         err = ep93xxfb_check_var(&info->var, info);
 537         if (err)
 538                 goto failed_check;
 539
 540         fbi->clk = devm_clk_get(&pdev->dev, NULL);
 541         if (IS_ERR(fbi->clk)) {
 542                 err = PTR_ERR(fbi->clk);
 543                 fbi->clk = NULL;
 544                 goto failed_check;
 545         }
 546
 547         ep93xxfb_set_par(info);
 548         err = clk_prepare_enable(fbi->clk);
 549         if (err)
 550                 goto failed_check;
 551
 552         err = register_framebuffer(info);
 553         if (err)
 554                 goto failed_framebuffer;
 555
 556         fb_info(info, "registered. Mode = %dx%d-%d\n",
 557                 info->var.xres, info->var.yres, info->var.bits_per_pixel);
 558         return 0;
 559
 560 failed_framebuffer:
 561         clk_disable_unprepare(fbi->clk);
 562 failed_check:
 563         if (fbi->mach_info->teardown)
 564                 fbi->mach_info->teardown(pdev);
 565 failed_resource:
 566         ep93xxfb_dealloc_videomem(info);
 567 failed_videomem:
 568         fb_dealloc_cmap(&info->cmap);
 569 failed_cmap:
 570         kfree(info);
 571
 572         return err;
 573 }
 574
 575 static void ep93xxfb_remove(struct platform_device *pdev)
 576 {
 577         struct fb_info *info = platform_get_drvdata(pdev);
 578         struct ep93xx_fbi *fbi = info->par;
 579
 580         unregister_framebuffer(info);
 581         clk_disable_unprepare(fbi->clk);
 582         ep93xxfb_dealloc_videomem(info);
 583         fb_dealloc_cmap(&info->cmap);
 584
 585         if (fbi->mach_info->teardown)
 586                 fbi->mach_info->teardown(pdev);
 587
 588         kfree(info);
 589 }
 590
 591 static struct platform_driver ep93xxfb_driver = {
 592         .probe          = ep93xxfb_probe,
 593         .remove_new     = ep93xxfb_remove,
 594         .driver = {
 595                 .name   = "ep93xx-fb",
 596         },
 597 };
 598 module_platform_driver(ep93xxfb_driver);
 599
 600 MODULE_DESCRIPTION("EP93XX Framebuffer Driver");
 601 MODULE_ALIAS("platform:ep93xx-fb");
 602 MODULE_AUTHOR("Ryan Mallon, "
 603               "H Hartley Sweeten <hsweeten@visionengravers.com");
 604 MODULE_LICENSE("GPL");