drivers/staging/udlfb/udlfb.c

   1 /*
   2  * udlfb.c -- Framebuffer driver for DisplayLink USB controller
   3  *
   4  * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
   5  * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
   6  * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License v2. See the file COPYING in the main directory of this archive for
  10  * more details.
  11  *
  12  * Layout is based on skeletonfb by James Simmons and Geert Uytterhoeven,
  13  * usb-skeleton by GregKH.
  14  *
  15  * Device-specific portions based on information from Displaylink, with work
  16  * from Florian Echtler, Henrik Bjerregaard Pedersen, and others.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/init.h>
  22 #include <linux/usb.h>
  23 #include <linux/uaccess.h>
  24 #include <linux/mm.h>
  25 #include <linux/fb.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/slab.h>
  28
  29 #include "udlfb.h"
  30
  31 static struct fb_fix_screeninfo dlfb_fix = {
  32         .id =           "udlfb",
  33         .type =         FB_TYPE_PACKED_PIXELS,
  34         .visual =       FB_VISUAL_TRUECOLOR,
  35         .xpanstep =     0,
  36         .ypanstep =     0,
  37         .ywrapstep =    0,
  38         .accel =        FB_ACCEL_NONE,
  39 };
  40
  41 static const u32 udlfb_info_flags = FBINFO_DEFAULT | FBINFO_READS_FAST |
  42 #ifdef FBINFO_VIRTFB
  43                 FBINFO_VIRTFB |
  44 #endif
  45                 FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT |
  46                 FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR;
  47
  48 /*
  49  * There are many DisplayLink-based products, all with unique PIDs. We are able
  50  * to support all volume ones (circa 2009) with a single driver, so we match
  51  * globally on VID. TODO: Probe() needs to detect when we might be running
  52  * "future" chips, and bail on those, so a compatible driver can match.
  53  */
  54 static struct usb_device_id id_table[] = {
  55         {.idVendor = 0x17e9, .match_flags = USB_DEVICE_ID_MATCH_VENDOR,},
  56         {},
  57 };
  58 MODULE_DEVICE_TABLE(usb, id_table);
  59
  60 #ifndef CONFIG_FB_DEFERRED_IO
  61 #warning Please set CONFIG_FB_DEFFERRED_IO option to support generic fbdev apps
  62 #endif
  63
  64 #ifndef CONFIG_FB_SYS_IMAGEBLIT
  65 #ifndef CONFIG_FB_SYS_IMAGEBLIT_MODULE
  66 #warning Please set CONFIG_FB_SYS_IMAGEBLIT option to support fb console
  67 #endif
  68 #endif
  69
  70 #ifndef CONFIG_FB_MODE_HELPERS
  71 #warning CONFIG_FB_MODE_HELPERS required. Expect build break
  72 #endif
  73
  74 /* dlfb keeps a list of urbs for efficient bulk transfers */
  75 static void dlfb_urb_completion(struct urb *urb);
  76 static struct urb *dlfb_get_urb(struct dlfb_data *dev);
  77 static int dlfb_submit_urb(struct dlfb_data *dev, struct urb * urb, size_t len);
  78 static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size);
  79 static void dlfb_free_urb_list(struct dlfb_data *dev);
  80
  81 /* other symbols with dependents */
  82 #ifdef CONFIG_FB_DEFERRED_IO
  83 static struct fb_deferred_io dlfb_defio;
  84 #endif
  85
  86 /*
  87  * All DisplayLink bulk operations start with 0xAF, followed by specific code
  88  * All operations are written to buffers which then later get sent to device
  89  */
  90 static char *dlfb_set_register(char *buf, u8 reg, u8 val)
  91 {
  92         *buf++ = 0xAF;
  93         *buf++ = 0x20;
  94         *buf++ = reg;
  95         *buf++ = val;
  96         return buf;
  97 }
  98
  99 static char *dlfb_vidreg_lock(char *buf)
 100 {
 101         return dlfb_set_register(buf, 0xFF, 0x00);
 102 }
 103
 104 static char *dlfb_vidreg_unlock(char *buf)
 105 {
 106         return dlfb_set_register(buf, 0xFF, 0xFF);
 107 }
 108
 109 /*
 110  * On/Off for driving the DisplayLink framebuffer to the display
 111  *  0x00 H and V sync on
 112  *  0x01 H and V sync off (screen blank but powered)
 113  *  0x07 DPMS powerdown (requires modeset to come back)
 114  */
 115 static char *dlfb_enable_hvsync(char *buf, bool enable)
 116 {
 117         if (enable)
 118                 return dlfb_set_register(buf, 0x1F, 0x00);
 119         else
 120                 return dlfb_set_register(buf, 0x1F, 0x07);
 121 }
 122
 123 static char *dlfb_set_color_depth(char *buf, u8 selection)
 124 {
 125         return dlfb_set_register(buf, 0x00, selection);
 126 }
 127
 128 static char *dlfb_set_base16bpp(char *wrptr, u32 base)
 129 {
 130         /* the base pointer is 16 bits wide, 0x20 is hi byte. */
 131         wrptr = dlfb_set_register(wrptr, 0x20, base >> 16);
 132         wrptr = dlfb_set_register(wrptr, 0x21, base >> 8);
 133         return dlfb_set_register(wrptr, 0x22, base);
 134 }
 135
 136 /*
 137  * DisplayLink HW has separate 16bpp and 8bpp framebuffers.
 138  * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer
 139  */
 140 static char *dlfb_set_base8bpp(char *wrptr, u32 base)
 141 {
 142         wrptr = dlfb_set_register(wrptr, 0x26, base >> 16);
 143         wrptr = dlfb_set_register(wrptr, 0x27, base >> 8);
 144         return dlfb_set_register(wrptr, 0x28, base);
 145 }
 146
 147 static char *dlfb_set_register_16(char *wrptr, u8 reg, u16 value)
 148 {
 149         wrptr = dlfb_set_register(wrptr, reg, value >> 8);
 150         return dlfb_set_register(wrptr, reg+1, value);
 151 }
 152
 153 /*
 154  * This is kind of weird because the controller takes some
 155  * register values in a different byte order than other registers.
 156  */
 157 static char *dlfb_set_register_16be(char *wrptr, u8 reg, u16 value)
 158 {
 159         wrptr = dlfb_set_register(wrptr, reg, value);
 160         return dlfb_set_register(wrptr, reg+1, value >> 8);
 161 }
 162
 163 /*
 164  * LFSR is linear feedback shift register. The reason we have this is
 165  * because the display controller needs to minimize the clock depth of
 166  * various counters used in the display path. So this code reverses the
 167  * provided value into the lfsr16 value by counting backwards to get
 168  * the value that needs to be set in the hardware comparator to get the
 169  * same actual count. This makes sense once you read above a couple of
 170  * times and think about it from a hardware perspective.
 171  */
 172 static u16 dlfb_lfsr16(u16 actual_count)
 173 {
 174         u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */
 175
 176         while (actual_count--) {
 177                 lv =     ((lv << 1) |
 178                         (((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1))
 179                         & 0xFFFF;
 180         }
 181
 182         return (u16) lv;
 183 }
 184
 185 /*
 186  * This does LFSR conversion on the value that is to be written.
 187  * See LFSR explanation above for more detail.
 188  */
 189 static char *dlfb_set_register_lfsr16(char *wrptr, u8 reg, u16 value)
 190 {
 191         return dlfb_set_register_16(wrptr, reg, dlfb_lfsr16(value));
 192 }
 193
 194 /*
 195  * This takes a standard fbdev screeninfo struct and all of its monitor mode
 196  * details and converts them into the DisplayLink equivalent register commands.
 197  */
 198 static char *dlfb_set_vid_cmds(char *wrptr, struct fb_var_screeninfo *var)
 199 {
 200         u16 xds, yds;
 201         u16 xde, yde;
 202         u16 yec;
 203
 204         /* x display start */
 205         xds = var->left_margin + var->hsync_len;
 206         wrptr = dlfb_set_register_lfsr16(wrptr, 0x01, xds);
 207         /* x display end */
 208         xde = xds + var->xres;
 209         wrptr = dlfb_set_register_lfsr16(wrptr, 0x03, xde);
 210
 211         /* y display start */
 212         yds = var->upper_margin + var->vsync_len;
 213         wrptr = dlfb_set_register_lfsr16(wrptr, 0x05, yds);
 214         /* y display end */
 215         yde = yds + var->yres;
 216         wrptr = dlfb_set_register_lfsr16(wrptr, 0x07, yde);
 217
 218         /* x end count is active + blanking - 1 */
 219         wrptr = dlfb_set_register_lfsr16(wrptr, 0x09,
 220                         xde + var->right_margin - 1);
 221
 222         /* libdlo hardcodes hsync start to 1 */
 223         wrptr = dlfb_set_register_lfsr16(wrptr, 0x0B, 1);
 224
 225         /* hsync end is width of sync pulse + 1 */
 226         wrptr = dlfb_set_register_lfsr16(wrptr, 0x0D, var->hsync_len + 1);
 227
 228         /* hpixels is active pixels */
 229         wrptr = dlfb_set_register_16(wrptr, 0x0F, var->xres);
 230
 231         /* yendcount is vertical active + vertical blanking */
 232         yec = var->yres + var->upper_margin + var->lower_margin +
 233                         var->vsync_len;
 234         wrptr = dlfb_set_register_lfsr16(wrptr, 0x11, yec);
 235
 236         /* libdlo hardcodes vsync start to 0 */
 237         wrptr = dlfb_set_register_lfsr16(wrptr, 0x13, 0);
 238
 239         /* vsync end is width of vsync pulse */
 240         wrptr = dlfb_set_register_lfsr16(wrptr, 0x15, var->vsync_len);
 241
 242         /* vpixels is active pixels */
 243         wrptr = dlfb_set_register_16(wrptr, 0x17, var->yres);
 244
 245         /* convert picoseconds to 5kHz multiple for pclk5k = x * 1E12/5k */
 246         wrptr = dlfb_set_register_16be(wrptr, 0x1B,
 247                         200*1000*1000/var->pixclock);
 248
 249         return wrptr;
 250 }
 251
 252 /*
 253  * This takes a standard fbdev screeninfo struct that was fetched or prepared
 254  * and then generates the appropriate command sequence that then drives the
 255  * display controller.
 256  */
 257 static int dlfb_set_video_mode(struct dlfb_data *dev,
 258                                 struct fb_var_screeninfo *var)
 259 {
 260         char *buf;
 261         char *wrptr;
 262         int retval = 0;
 263         int writesize;
 264         struct urb *urb;
 265
 266         if (!atomic_read(&dev->usb_active))
 267                 return -EPERM;
 268
 269         urb = dlfb_get_urb(dev);
 270         if (!urb)
 271                 return -ENOMEM;
 272         buf = (char *) urb->transfer_buffer;
 273
 274         /*
 275         * This first section has to do with setting the base address on the
 276         * controller * associated with the display. There are 2 base
 277         * pointers, currently, we only * use the 16 bpp segment.
 278         */
 279         wrptr = dlfb_vidreg_lock(buf);
 280         wrptr = dlfb_set_color_depth(wrptr, 0x00);
 281         /* set base for 16bpp segment to 0 */
 282         wrptr = dlfb_set_base16bpp(wrptr, 0);
 283         /* set base for 8bpp segment to end of fb */
 284         wrptr = dlfb_set_base8bpp(wrptr, dev->info->fix.smem_len);
 285
 286         wrptr = dlfb_set_vid_cmds(wrptr, var);
 287         wrptr = dlfb_enable_hvsync(wrptr, true);
 288         wrptr = dlfb_vidreg_unlock(wrptr);
 289
 290         writesize = wrptr - buf;
 291
 292         retval = dlfb_submit_urb(dev, urb, writesize);
 293
 294         return retval;
 295 }
 296
 297 static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)
 298 {
 299         unsigned long start = vma->vm_start;
 300         unsigned long size = vma->vm_end - vma->vm_start;
 301         unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
 302         unsigned long page, pos;
 303         struct dlfb_data *dev = info->par;
 304
 305         dl_notice("MMAP: %lu %u\n", offset + size, info->fix.smem_len);
 306
 307         if (offset + size > info->fix.smem_len)
 308                 return -EINVAL;
 309
 310         pos = (unsigned long)info->fix.smem_start + offset;
 311
 312         while (size > 0) {
 313                 page = vmalloc_to_pfn((void *)pos);
 314                 if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))
 315                         return -EAGAIN;
 316
 317                 start += PAGE_SIZE;
 318                 pos += PAGE_SIZE;
 319                 if (size > PAGE_SIZE)
 320                         size -= PAGE_SIZE;
 321                 else
 322                         size = 0;
 323         }
 324
 325         vma->vm_flags |= VM_RESERVED;   /* avoid to swap out this VMA */
 326         return 0;
 327
 328 }
 329
 330 /*
 331  * Trims identical data from front and back of line
 332  * Sets new front buffer address and width
 333  * And returns byte count of identical pixels
 334  * Assumes CPU natural alignment (unsigned long)
 335  * for back and front buffer ptrs and width
 336  */
 337 static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)
 338 {
 339         int j, k;
 340         const unsigned long *back = (const unsigned long *) bback;
 341         const unsigned long *front = (const unsigned long *) *bfront;
 342         const int width = *width_bytes / sizeof(unsigned long);
 343         int identical = width;
 344         int start = width;
 345         int end = width;
 346
 347         prefetch((void *) front);
 348         prefetch((void *) back);
 349
 350         for (j = 0; j < width; j++) {
 351                 if (back[j] != front[j]) {
 352                         start = j;
 353                         break;
 354                 }
 355         }
 356
 357         for (k = width - 1; k > j; k--) {
 358                 if (back[k] != front[k]) {
 359                         end = k+1;
 360                         break;
 361                 }
 362         }
 363
 364         identical = start + (width - end);
 365         *bfront = (u8 *) &front[start];
 366         *width_bytes = (end - start) * sizeof(unsigned long);
 367
 368         return identical * sizeof(unsigned long);
 369 }
 370
 371 /*
 372  * Render a command stream for an encoded horizontal line segment of pixels.
 373  *
 374  * A command buffer holds several commands.
 375  * It always begins with a fresh command header
 376  * (the protocol doesn't require this, but we enforce it to allow
 377  * multiple buffers to be potentially encoded and sent in parallel).
 378  * A single command encodes one contiguous horizontal line of pixels
 379  *
 380  * The function relies on the client to do all allocation, so that
 381  * rendering can be done directly to output buffers (e.g. USB URBs).
 382  * The function fills the supplied command buffer, providing information
 383  * on where it left off, so the client may call in again with additional
 384  * buffers if the line will take several buffers to complete.
 385  *
 386  * A single command can transmit a maximum of 256 pixels,
 387  * regardless of the compression ratio (protocol design limit).
 388  * To the hardware, 0 for a size byte means 256
 389  *
 390  * Rather than 256 pixel commands which are either rl or raw encoded,
 391  * the rlx command simply assumes alternating raw and rl spans within one cmd.
 392  * This has a slightly larger header overhead, but produces more even results.
 393  * It also processes all data (read and write) in a single pass.
 394  * Performance benchmarks of common cases show it having just slightly better
 395  * compression than 256 pixel raw -or- rle commands, with similar CPU consumpion.
 396  * But for very rl friendly data, will compress not quite as well.
 397  */
 398 static void dlfb_compress_hline(
 399         const uint16_t **pixel_start_ptr,
 400         const uint16_t *const pixel_end,
 401         uint32_t *device_address_ptr,
 402         uint8_t **command_buffer_ptr,
 403         const uint8_t *const cmd_buffer_end)
 404 {
 405         const uint16_t *pixel = *pixel_start_ptr;
 406         uint32_t dev_addr  = *device_address_ptr;
 407         uint8_t *cmd = *command_buffer_ptr;
 408         const int bpp = 2;
 409
 410         while ((pixel_end > pixel) &&
 411                (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) {
 412                 uint8_t *raw_pixels_count_byte = 0;
 413                 uint8_t *cmd_pixels_count_byte = 0;
 414                 const uint16_t *raw_pixel_start = 0;
 415                 const uint16_t *cmd_pixel_start, *cmd_pixel_end = 0;
 416                 const uint32_t be_dev_addr = cpu_to_be32(dev_addr);
 417
 418                 prefetchw((void *) cmd); /* pull in one cache line at least */
 419
 420                 *cmd++ = 0xAF;
 421                 *cmd++ = 0x6B;
 422                 *cmd++ = (uint8_t) ((be_dev_addr >> 8) & 0xFF);
 423                 *cmd++ = (uint8_t) ((be_dev_addr >> 16) & 0xFF);
 424                 *cmd++ = (uint8_t) ((be_dev_addr >> 24) & 0xFF);
 425
 426                 cmd_pixels_count_byte = cmd++; /*  we'll know this later */
 427                 cmd_pixel_start = pixel;
 428
 429                 raw_pixels_count_byte = cmd++; /*  we'll know this later */
 430                 raw_pixel_start = pixel;
 431
 432                 cmd_pixel_end = pixel + min(MAX_CMD_PIXELS + 1,
 433                         min((int)(pixel_end - pixel),
 434                             (int)(cmd_buffer_end - cmd) / bpp));
 435
 436                 prefetch_range((void *) pixel, (cmd_pixel_end - pixel) * bpp);
 437
 438                 while (pixel < cmd_pixel_end) {
 439                         const uint16_t * const repeating_pixel = pixel;
 440
 441                         *(uint16_t *)cmd = cpu_to_be16p(pixel);
 442                         cmd += 2;
 443                         pixel++;
 444
 445                         if (unlikely((pixel < cmd_pixel_end) &&
 446                                      (*pixel == *repeating_pixel))) {
 447                                 /* go back and fill in raw pixel count */
 448                                 *raw_pixels_count_byte = ((repeating_pixel -
 449                                                 raw_pixel_start) + 1) & 0xFF;
 450
 451                                 while ((pixel < cmd_pixel_end)
 452                                        && (*pixel == *repeating_pixel)) {
 453                                         pixel++;
 454                                 }
 455
 456                                 /* immediately after raw data is repeat byte */
 457                                 *cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF;
 458
 459                                 /* Then start another raw pixel span */
 460                                 raw_pixel_start = pixel;
 461                                 raw_pixels_count_byte = cmd++;
 462                         }
 463                 }
 464
 465                 if (pixel > raw_pixel_start) {
 466                         /* finalize last RAW span */
 467                         *raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF;
 468                 }
 469
 470                 *cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF;
 471                 dev_addr += (pixel - cmd_pixel_start) * bpp;
 472         }
 473
 474         if (cmd_buffer_end <= MIN_RLX_CMD_BYTES + cmd) {
 475                 /* Fill leftover bytes with no-ops */
 476                 if (cmd_buffer_end > cmd)
 477                         memset(cmd, 0xAF, cmd_buffer_end - cmd);
 478                 cmd = (uint8_t *) cmd_buffer_end;
 479         }
 480
 481         *command_buffer_ptr = cmd;
 482         *pixel_start_ptr = pixel;
 483         *device_address_ptr = dev_addr;
 484
 485         return;
 486 }
 487
 488 /*
 489  * There are 3 copies of every pixel: The front buffer that the fbdev
 490  * client renders to, the actual framebuffer across the USB bus in hardware
 491  * (that we can only write to, slowly, and can never read), and (optionally)
 492  * our shadow copy that tracks what's been sent to that hardware buffer.
 493  */
 494 static void dlfb_render_hline(struct dlfb_data *dev, struct urb **urb_ptr,
 495                               const char *front, char **urb_buf_ptr,
 496                               u32 byte_offset, u32 byte_width,
 497                               int *ident_ptr, int *sent_ptr)
 498 {
 499         const u8 *line_start, *line_end, *next_pixel;
 500         u32 dev_addr = dev->base16 + byte_offset;
 501         struct urb *urb = *urb_ptr;
 502         u8 *cmd = *urb_buf_ptr;
 503         u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length;
 504
 505         line_start = (u8 *) (front + byte_offset);
 506         next_pixel = line_start;
 507         line_end = next_pixel + byte_width;
 508
 509         if (dev->backing_buffer) {
 510                 int offset;
 511                 const u8 *back_start = (u8 *) (dev->backing_buffer
 512                                                 + byte_offset);
 513
 514                 *ident_ptr += dlfb_trim_hline(back_start, &next_pixel,
 515                         &byte_width);
 516
 517                 offset = next_pixel - line_start;
 518                 line_end = next_pixel + byte_width;
 519                 dev_addr += offset;
 520                 back_start += offset;
 521                 line_start += offset;
 522
 523                 memcpy((char *)back_start, (char *) line_start,
 524                        byte_width);
 525         }
 526
 527         while (next_pixel < line_end) {
 528
 529                 dlfb_compress_hline((const uint16_t **) &next_pixel,
 530                              (const uint16_t *) line_end, &dev_addr,
 531                         (u8 **) &cmd, (u8 *) cmd_end);
 532
 533                 if (cmd >= cmd_end) {
 534                         int len = cmd - (u8 *) urb->transfer_buffer;
 535                         if (dlfb_submit_urb(dev, urb, len))
 536                                 return; /* lost pixels is set */
 537                         *sent_ptr += len;
 538                         urb = dlfb_get_urb(dev);
 539                         if (!urb)
 540                                 return; /* lost_pixels is set */
 541                         *urb_ptr = urb;
 542                         cmd = urb->transfer_buffer;
 543                         cmd_end = &cmd[urb->transfer_buffer_length];
 544                 }
 545         }
 546
 547         *urb_buf_ptr = cmd;
 548 }
 549
 550 int dlfb_handle_damage(struct dlfb_data *dev, int x, int y,
 551                int width, int height, char *data)
 552 {
 553         int i, ret;
 554         char *cmd;
 555         cycles_t start_cycles, end_cycles;
 556         int bytes_sent = 0;
 557         int bytes_identical = 0;
 558         struct urb *urb;
 559         int aligned_x;
 560
 561         start_cycles = get_cycles();
 562
 563         aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long));
 564         width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long));
 565         x = aligned_x;
 566
 567         if ((width <= 0) ||
 568             (x + width > dev->info->var.xres) ||
 569             (y + height > dev->info->var.yres))
 570                 return -EINVAL;
 571
 572         if (!atomic_read(&dev->usb_active))
 573                 return 0;
 574
 575         urb = dlfb_get_urb(dev);
 576         if (!urb)
 577                 return 0;
 578         cmd = urb->transfer_buffer;
 579
 580         for (i = y; i < y + height ; i++) {
 581                 const int line_offset = dev->info->fix.line_length * i;
 582                 const int byte_offset = line_offset + (x * BPP);
 583
 584                 dlfb_render_hline(dev, &urb, (char *) dev->info->fix.smem_start,
 585                                   &cmd, byte_offset, width * BPP,
 586                                   &bytes_identical, &bytes_sent);
 587         }
 588
 589         if (cmd > (char *) urb->transfer_buffer) {
 590                 /* Send partial buffer remaining before exiting */
 591                 int len = cmd - (char *) urb->transfer_buffer;
 592                 ret = dlfb_submit_urb(dev, urb, len);
 593                 bytes_sent += len;
 594         } else
 595                 dlfb_urb_completion(urb);
 596
 597         atomic_add(bytes_sent, &dev->bytes_sent);
 598         atomic_add(bytes_identical, &dev->bytes_identical);
 599         atomic_add(width*height*2, &dev->bytes_rendered);
 600         end_cycles = get_cycles();
 601         atomic_add(((unsigned int) ((end_cycles - start_cycles)
 602                     >> 10)), /* Kcycles */
 603                    &dev->cpu_kcycles_used);
 604
 605         return 0;
 606 }
 607
 608 static ssize_t dlfb_ops_read(struct fb_info *info, char __user *buf,
 609                          size_t count, loff_t *ppos)
 610 {
 611         ssize_t result = -ENOSYS;
 612
 613 #if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
 614         result = fb_sys_read(info, buf, count, ppos);
 615 #endif
 616
 617         return result;
 618 }
 619
 620 /*
 621  * Path triggered by usermode clients who write to filesystem
 622  * e.g. cat filename > /dev/fb1
 623  * Not used by X Windows or text-mode console. But useful for testing.
 624  * Slow because of extra copy and we must assume all pixels dirty.
 625  */
 626 static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
 627                           size_t count, loff_t *ppos)
 628 {
 629         ssize_t result = -ENOSYS;
 630         struct dlfb_data *dev = info->par;
 631         u32 offset = (u32) *ppos;
 632
 633 #if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
 634
 635         result = fb_sys_write(info, buf, count, ppos);
 636
 637         if (result > 0) {
 638                 int start = max((int)(offset / info->fix.line_length) - 1, 0);
 639                 int lines = min((u32)((result / info->fix.line_length) + 1),
 640                                 (u32)info->var.yres);
 641
 642                 dlfb_handle_damage(dev, 0, start, info->var.xres,
 643                         lines, info->screen_base);
 644         }
 645 #endif
 646
 647         return result;
 648 }
 649
 650 /* hardware has native COPY command (see libdlo), but not worth it for fbcon */
 651 static void dlfb_ops_copyarea(struct fb_info *info,
 652                                 const struct fb_copyarea *area)
 653 {
 654
 655         struct dlfb_data *dev = info->par;
 656
 657 #if defined CONFIG_FB_SYS_COPYAREA || defined CONFIG_FB_SYS_COPYAREA_MODULE
 658
 659         sys_copyarea(info, area);
 660
 661         dlfb_handle_damage(dev, area->dx, area->dy,
 662                         area->width, area->height, info->screen_base);
 663 #endif
 664         atomic_inc(&dev->copy_count);
 665
 666 }
 667
 668 static void dlfb_ops_imageblit(struct fb_info *info,
 669                                 const struct fb_image *image)
 670 {
 671         struct dlfb_data *dev = info->par;
 672
 673 #if defined CONFIG_FB_SYS_IMAGEBLIT || defined CONFIG_FB_SYS_IMAGEBLIT_MODULE
 674
 675         sys_imageblit(info, image);
 676
 677         dlfb_handle_damage(dev, image->dx, image->dy,
 678                         image->width, image->height, info->screen_base);
 679
 680 #endif
 681
 682         atomic_inc(&dev->blit_count);
 683 }
 684
 685 static void dlfb_ops_fillrect(struct fb_info *info,
 686                           const struct fb_fillrect *rect)
 687 {
 688         struct dlfb_data *dev = info->par;
 689
 690 #if defined CONFIG_FB_SYS_FILLRECT || defined CONFIG_FB_SYS_FILLRECT_MODULE
 691
 692         sys_fillrect(info, rect);
 693
 694         dlfb_handle_damage(dev, rect->dx, rect->dy, rect->width,
 695                               rect->height, info->screen_base);
 696 #endif
 697
 698         atomic_inc(&dev->fill_count);
 699
 700 }
 701
 702 static void dlfb_get_edid(struct dlfb_data *dev)
 703 {
 704         int i;
 705         int ret;
 706         char rbuf[2];
 707
 708         for (i = 0; i < sizeof(dev->edid); i++) {
 709                 ret = usb_control_msg(dev->udev,
 710                                     usb_rcvctrlpipe(dev->udev, 0), (0x02),
 711                                     (0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2,
 712                                     0);
 713                 dev->edid[i] = rbuf[1];
 714         }
 715 }
 716
 717 static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd,
 718                                 unsigned long arg)
 719 {
 720
 721         struct dlfb_data *dev = info->par;
 722         struct dloarea *area = NULL;
 723
 724         if (!atomic_read(&dev->usb_active))
 725                 return 0;
 726
 727         /* TODO: Update X server to get this from sysfs instead */
 728         if (cmd == DLFB_IOCTL_RETURN_EDID) {
 729                 char *edid = (char *)arg;
 730                 dlfb_get_edid(dev);
 731                 if (copy_to_user(edid, dev->edid, sizeof(dev->edid)))
 732                         return -EFAULT;
 733                 return 0;
 734         }
 735
 736         /* TODO: Help propose a standard fb.h ioctl to report mmap damage */
 737         if (cmd == DLFB_IOCTL_REPORT_DAMAGE) {
 738
 739                 area = (struct dloarea *)arg;
 740
 741                 if (area->x < 0)
 742                         area->x = 0;
 743
 744                 if (area->x > info->var.xres)
 745                         area->x = info->var.xres;
 746
 747                 if (area->y < 0)
 748                         area->y = 0;
 749
 750                 if (area->y > info->var.yres)
 751                         area->y = info->var.yres;
 752
 753                 atomic_set(&dev->use_defio, 0);
 754
 755                 dlfb_handle_damage(dev, area->x, area->y, area->w, area->h,
 756                            info->screen_base);
 757                 atomic_inc(&dev->damage_count);
 758         }
 759
 760         return 0;
 761 }
 762
 763 /* taken from vesafb */
 764 static int
 765 dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green,
 766                unsigned blue, unsigned transp, struct fb_info *info)
 767 {
 768         int err = 0;
 769
 770         if (regno >= info->cmap.len)
 771                 return 1;
 772
 773         if (regno < 16) {
 774                 if (info->var.red.offset == 10) {
 775                         /* 1:5:5:5 */
 776                         ((u32 *) (info->pseudo_palette))[regno] =
 777                             ((red & 0xf800) >> 1) |
 778                             ((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11);
 779                 } else {
 780                         /* 0:5:6:5 */
 781                         ((u32 *) (info->pseudo_palette))[regno] =
 782                             ((red & 0xf800)) |
 783                             ((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11);
 784                 }
 785         }
 786
 787         return err;
 788 }
 789
 790 /*
 791  * It's common for several clients to have framebuffer open simultaneously.
 792  * e.g. both fbcon and X. Makes things interesting.
 793  */
 794 static int dlfb_ops_open(struct fb_info *info, int user)
 795 {
 796         struct dlfb_data *dev = info->par;
 797
 798 /*      if (user == 0)
 799  *              We could special case kernel mode clients (fbcon) here
 800  */
 801
 802         mutex_lock(&dev->fb_open_lock);
 803
 804         dev->fb_count++;
 805
 806 #ifdef CONFIG_FB_DEFERRED_IO
 807         if ((atomic_read(&dev->use_defio)) && (info->fbdefio == NULL)) {
 808                 /* enable defio */
 809                 info->fbdefio = &dlfb_defio;
 810                 fb_deferred_io_init(info);
 811         }
 812 #endif
 813
 814         dl_notice("open /dev/fb%d user=%d fb_info=%p count=%d\n",
 815             info->node, user, info, dev->fb_count);
 816
 817         mutex_unlock(&dev->fb_open_lock);
 818
 819         return 0;
 820 }
 821
 822 static int dlfb_ops_release(struct fb_info *info, int user)
 823 {
 824         struct dlfb_data *dev = info->par;
 825
 826         mutex_lock(&dev->fb_open_lock);
 827
 828         dev->fb_count--;
 829
 830 #ifdef CONFIG_FB_DEFERRED_IO
 831         if ((dev->fb_count == 0) && (info->fbdefio)) {
 832                 fb_deferred_io_cleanup(info);
 833                 info->fbdefio = NULL;
 834                 info->fbops->fb_mmap = dlfb_ops_mmap;
 835         }
 836 #endif
 837
 838         dl_notice("release /dev/fb%d user=%d count=%d\n",
 839                   info->node, user, dev->fb_count);
 840
 841         mutex_unlock(&dev->fb_open_lock);
 842
 843         return 0;
 844 }
 845
 846 /*
 847  * Called when all client interfaces to start transactions have been disabled,
 848  * and all references to our device instance (dlfb_data) are released.
 849  * Every transaction must have a reference, so we know are fully spun down
 850  */
 851 static void dlfb_delete(struct kref *kref)
 852 {
 853         struct dlfb_data *dev = container_of(kref, struct dlfb_data, kref);
 854
 855         if (dev->backing_buffer)
 856                 vfree(dev->backing_buffer);
 857
 858         mutex_destroy(&dev->fb_open_lock);
 859
 860         kfree(dev);
 861 }
 862
 863 /*
 864  * Called by fbdev as last part of unregister_framebuffer() process
 865  * No new clients can open connections. Deallocate everything fb_info.
 866  */
 867 static void dlfb_ops_destroy(struct fb_info *info)
 868 {
 869         struct dlfb_data *dev = info->par;
 870
 871         if (info->cmap.len != 0)
 872                 fb_dealloc_cmap(&info->cmap);
 873         if (info->monspecs.modedb)
 874                 fb_destroy_modedb(info->monspecs.modedb);
 875         if (info->screen_base)
 876                 vfree(info->screen_base);
 877
 878         fb_destroy_modelist(&info->modelist);
 879
 880         framebuffer_release(info);
 881
 882         /* ref taken before register_framebuffer() for dlfb_data clients */
 883         kref_put(&dev->kref, dlfb_delete);
 884 }
 885
 886 /*
 887  * Check whether a video mode is supported by the DisplayLink chip
 888  * We start from monitor's modes, so don't need to filter that here
 889  */
 890 static int dlfb_is_valid_mode(struct fb_videomode *mode,
 891                 struct fb_info *info)
 892 {
 893         struct dlfb_data *dev = info->par;
 894
 895         if (mode->xres * mode->yres > dev->sku_pixel_limit)
 896                 return 0;
 897
 898         return 1;
 899 }
 900
 901 static void dlfb_var_color_format(struct fb_var_screeninfo *var)
 902 {
 903         const struct fb_bitfield red = { 11, 5, 0 };
 904         const struct fb_bitfield green = { 5, 6, 0 };
 905         const struct fb_bitfield blue = { 0, 5, 0 };
 906
 907         var->bits_per_pixel = 16;
 908         var->red = red;
 909         var->green = green;
 910         var->blue = blue;
 911 }
 912
 913 static int dlfb_ops_check_var(struct fb_var_screeninfo *var,
 914                                 struct fb_info *info)
 915 {
 916         struct fb_videomode mode;
 917
 918         /* TODO: support dynamically changing framebuffer size */
 919         if ((var->xres * var->yres * 2) > info->fix.smem_len)
 920                 return -EINVAL;
 921
 922         /* set device-specific elements of var unrelated to mode */
 923         dlfb_var_color_format(var);
 924
 925         fb_var_to_videomode(&mode, var);
 926
 927         if (!dlfb_is_valid_mode(&mode, info))
 928                 return -EINVAL;
 929
 930         return 0;
 931 }
 932
 933 static int dlfb_ops_set_par(struct fb_info *info)
 934 {
 935         struct dlfb_data *dev = info->par;
 936
 937         dl_notice("set_par mode %dx%d\n", info->var.xres, info->var.yres);
 938
 939         return dlfb_set_video_mode(dev, &info->var);
 940 }
 941
 942 /*
 943  * In order to come back from full DPMS off, we need to set the mode again
 944  */
 945 static int dlfb_ops_blank(int blank_mode, struct fb_info *info)
 946 {
 947         struct dlfb_data *dev = info->par;
 948
 949         if (blank_mode != FB_BLANK_UNBLANK) {
 950                 char *bufptr;
 951                 struct urb *urb;
 952
 953                 urb = dlfb_get_urb(dev);
 954                 if (!urb)
 955                         return 0;
 956
 957                 bufptr = (char *) urb->transfer_buffer;
 958                 bufptr = dlfb_vidreg_lock(bufptr);
 959                 bufptr = dlfb_enable_hvsync(bufptr, false);
 960                 bufptr = dlfb_vidreg_unlock(bufptr);
 961
 962                 dlfb_submit_urb(dev, urb, bufptr -
 963                                 (char *) urb->transfer_buffer);
 964         } else {
 965                 dlfb_set_video_mode(dev, &info->var);
 966         }
 967
 968         return 0;
 969 }
 970
 971 static struct fb_ops dlfb_ops = {
 972         .owner = THIS_MODULE,
 973         .fb_read = dlfb_ops_read,
 974         .fb_write = dlfb_ops_write,
 975         .fb_setcolreg = dlfb_ops_setcolreg,
 976         .fb_fillrect = dlfb_ops_fillrect,
 977         .fb_copyarea = dlfb_ops_copyarea,
 978         .fb_imageblit = dlfb_ops_imageblit,
 979         .fb_mmap = dlfb_ops_mmap,
 980         .fb_ioctl = dlfb_ops_ioctl,
 981         .fb_open = dlfb_ops_open,
 982         .fb_release = dlfb_ops_release,
 983         .fb_blank = dlfb_ops_blank,
 984         .fb_check_var = dlfb_ops_check_var,
 985         .fb_set_par = dlfb_ops_set_par,
 986 };
 987
 988 /*
 989  * Calls dlfb_get_edid() to query the EDID of attached monitor via usb cmds
 990  * Then parses EDID into three places used by various parts of fbdev:
 991  * fb_var_screeninfo contains the timing of the monitor's preferred mode
 992  * fb_info.monspecs is full parsed EDID info, including monspecs.modedb
 993  * fb_info.modelist is a linked list of all monitor & VESA modes which work
 994  *
 995  * If EDID is not readable/valid, then modelist is all VESA modes,
 996  * monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode
 997  * Returns 0 if EDID parses successfully
 998  */
 999 static int dlfb_parse_edid(struct dlfb_data *dev,
1000                             struct fb_var_screeninfo *var,
1001                             struct fb_info *info)
1002 {
1003         int i;
1004         const struct fb_videomode *default_vmode = NULL;
1005         int result = 0;
1006
1007         fb_destroy_modelist(&info->modelist);
1008         memset(&info->monspecs, 0, sizeof(info->monspecs));
1009
1010         dlfb_get_edid(dev);
1011         fb_edid_to_monspecs(dev->edid, &info->monspecs);
1012
1013         if (info->monspecs.modedb_len > 0) {
1014
1015                 for (i = 0; i < info->monspecs.modedb_len; i++) {
1016                         if (dlfb_is_valid_mode(&info->monspecs.modedb[i], info))
1017                                 fb_add_videomode(&info->monspecs.modedb[i],
1018                                         &info->modelist);
1019                 }
1020
1021                 default_vmode = fb_find_best_display(&info->monspecs,
1022                                                      &info->modelist);
1023         } else {
1024                 struct fb_videomode fb_vmode = {0};
1025
1026                 dl_err("Unable to get valid EDID from device/display\n");
1027                 result = 1;
1028
1029                 /*
1030                  * Add the standard VESA modes to our modelist
1031                  * Since we don't have EDID, there may be modes that
1032                  * overspec monitor and/or are incorrect aspect ratio, etc.
1033                  * But at least the user has a chance to choose
1034                  */
1035                 for (i = 0; i < VESA_MODEDB_SIZE; i++) {
1036                         if (dlfb_is_valid_mode((struct fb_videomode *)
1037                                                 &vesa_modes[i], info))
1038                                 fb_add_videomode(&vesa_modes[i],
1039                                                  &info->modelist);
1040                 }
1041
1042                 /*
1043                  * default to resolution safe for projectors
1044                  * (since they are most common case without EDID)
1045                  */
1046                 fb_vmode.xres = 800;
1047                 fb_vmode.yres = 600;
1048                 fb_vmode.refresh = 60;
1049                 default_vmode = fb_find_nearest_mode(&fb_vmode,
1050                                                      &info->modelist);
1051         }
1052
1053         fb_videomode_to_var(var, default_vmode);
1054         dlfb_var_color_format(var);
1055
1056         return result;
1057 }
1058
1059 static ssize_t metrics_bytes_rendered_show(struct device *fbdev,
1060                                    struct device_attribute *a, char *buf) {
1061         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1062         struct dlfb_data *dev = fb_info->par;
1063         return snprintf(buf, PAGE_SIZE, "%u\n",
1064                         atomic_read(&dev->bytes_rendered));
1065 }
1066
1067 static ssize_t metrics_bytes_identical_show(struct device *fbdev,
1068                                    struct device_attribute *a, char *buf) {
1069         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1070         struct dlfb_data *dev = fb_info->par;
1071         return snprintf(buf, PAGE_SIZE, "%u\n",
1072                         atomic_read(&dev->bytes_identical));
1073 }
1074
1075 static ssize_t metrics_bytes_sent_show(struct device *fbdev,
1076                                    struct device_attribute *a, char *buf) {
1077         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1078         struct dlfb_data *dev = fb_info->par;
1079         return snprintf(buf, PAGE_SIZE, "%u\n",
1080                         atomic_read(&dev->bytes_sent));
1081 }
1082
1083 static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev,
1084                                    struct device_attribute *a, char *buf) {
1085         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1086         struct dlfb_data *dev = fb_info->par;
1087         return snprintf(buf, PAGE_SIZE, "%u\n",
1088                         atomic_read(&dev->cpu_kcycles_used));
1089 }
1090
1091 static ssize_t metrics_misc_show(struct device *fbdev,
1092                                    struct device_attribute *a, char *buf) {
1093         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1094         struct dlfb_data *dev = fb_info->par;
1095         return snprintf(buf, PAGE_SIZE,
1096                         "Calls to\ndamage: %u\nblit: %u\n"
1097                         "defio faults: %u\ncopy: %u\n"
1098                         "fill: %u\n\n"
1099                         "active framebuffer clients: %d\n"
1100                         "urbs available %d(%d)\n"
1101                         "Shadow framebuffer in use? %s\n"
1102                         "Any lost pixels? %s\n",
1103                         atomic_read(&dev->damage_count),
1104                         atomic_read(&dev->blit_count),
1105                         atomic_read(&dev->defio_fault_count),
1106                         atomic_read(&dev->copy_count),
1107                         atomic_read(&dev->fill_count),
1108                         dev->fb_count,
1109                         dev->urbs.available, dev->urbs.limit_sem.count,
1110                         (dev->backing_buffer) ? "yes" : "no",
1111                         atomic_read(&dev->lost_pixels) ? "yes" : "no");
1112 }
1113
1114 static ssize_t edid_show(struct file *filp, struct kobject *kobj,
1115                          struct bin_attribute *a,
1116                          char *buf, loff_t off, size_t count) {
1117         struct device *fbdev = container_of(kobj, struct device, kobj);
1118         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1119         struct dlfb_data *dev = fb_info->par;
1120         char *edid = &dev->edid[0];
1121         const size_t size = sizeof(dev->edid);
1122
1123         if (dlfb_parse_edid(dev, &fb_info->var, fb_info))
1124                 return 0;
1125
1126         if (off >= size)
1127                 return 0;
1128
1129         if (off + count > size)
1130                 count = size - off;
1131         memcpy(buf, edid + off, count);
1132
1133         return count;
1134 }
1135
1136
1137 static ssize_t metrics_reset_store(struct device *fbdev,
1138                            struct device_attribute *attr,
1139                            const char *buf, size_t count)
1140 {
1141         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1142         struct dlfb_data *dev = fb_info->par;
1143
1144         atomic_set(&dev->bytes_rendered, 0);
1145         atomic_set(&dev->bytes_identical, 0);
1146         atomic_set(&dev->bytes_sent, 0);
1147         atomic_set(&dev->cpu_kcycles_used, 0);
1148         atomic_set(&dev->blit_count, 0);
1149         atomic_set(&dev->copy_count, 0);
1150         atomic_set(&dev->fill_count, 0);
1151         atomic_set(&dev->defio_fault_count, 0);
1152         atomic_set(&dev->damage_count, 0);
1153
1154         return count;
1155 }
1156
1157 static ssize_t use_defio_show(struct device *fbdev,
1158                                    struct device_attribute *a, char *buf) {
1159         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1160         struct dlfb_data *dev = fb_info->par;
1161         return snprintf(buf, PAGE_SIZE, "%d\n",
1162                         atomic_read(&dev->use_defio));
1163 }
1164
1165 static ssize_t use_defio_store(struct device *fbdev,
1166                            struct device_attribute *attr,
1167                            const char *buf, size_t count)
1168 {
1169         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1170         struct dlfb_data *dev = fb_info->par;
1171
1172         if (count > 0) {
1173                 if (buf[0] == '0')
1174                         atomic_set(&dev->use_defio, 0);
1175                 if (buf[0] == '1')
1176                         atomic_set(&dev->use_defio, 1);
1177         }
1178         return count;
1179 }
1180
1181 static struct bin_attribute edid_attr = {
1182         .attr.name = "edid",
1183         .attr.mode = 0444,
1184         .size = 128,
1185         .read = edid_show,
1186 };
1187
1188 static struct device_attribute fb_device_attrs[] = {
1189         __ATTR_RO(metrics_bytes_rendered),
1190         __ATTR_RO(metrics_bytes_identical),
1191         __ATTR_RO(metrics_bytes_sent),
1192         __ATTR_RO(metrics_cpu_kcycles_used),
1193         __ATTR_RO(metrics_misc),
1194         __ATTR(metrics_reset, S_IWUGO, NULL, metrics_reset_store),
1195         __ATTR_RW(use_defio),
1196 };
1197
1198 #ifdef CONFIG_FB_DEFERRED_IO
1199 static void dlfb_dpy_deferred_io(struct fb_info *info,
1200                                 struct list_head *pagelist)
1201 {
1202         struct page *cur;
1203         struct fb_deferred_io *fbdefio = info->fbdefio;
1204         struct dlfb_data *dev = info->par;
1205         struct urb *urb;
1206         char *cmd;
1207         cycles_t start_cycles, end_cycles;
1208         int bytes_sent = 0;
1209         int bytes_identical = 0;
1210         int bytes_rendered = 0;
1211         int fault_count = 0;
1212
1213         if (!atomic_read(&dev->use_defio))
1214                 return;
1215
1216         if (!atomic_read(&dev->usb_active))
1217                 return;
1218
1219         start_cycles = get_cycles();
1220
1221         urb = dlfb_get_urb(dev);
1222         if (!urb)
1223                 return;
1224         cmd = urb->transfer_buffer;
1225
1226         /* walk the written page list and render each to device */
1227         list_for_each_entry(cur, &fbdefio->pagelist, lru) {
1228                 dlfb_render_hline(dev, &urb, (char *) info->fix.smem_start,
1229                                   &cmd, cur->index << PAGE_SHIFT,
1230                                   PAGE_SIZE, &bytes_identical, &bytes_sent);
1231                 bytes_rendered += PAGE_SIZE;
1232                 fault_count++;
1233         }
1234
1235         if (cmd > (char *) urb->transfer_buffer) {
1236                 /* Send partial buffer remaining before exiting */
1237                 int len = cmd - (char *) urb->transfer_buffer;
1238                 dlfb_submit_urb(dev, urb, len);
1239                 bytes_sent += len;
1240         } else
1241                 dlfb_urb_completion(urb);
1242
1243         atomic_add(fault_count, &dev->defio_fault_count);
1244         atomic_add(bytes_sent, &dev->bytes_sent);
1245         atomic_add(bytes_identical, &dev->bytes_identical);
1246         atomic_add(bytes_rendered, &dev->bytes_rendered);
1247         end_cycles = get_cycles();
1248         atomic_add(((unsigned int) ((end_cycles - start_cycles)
1249                     >> 10)), /* Kcycles */
1250                    &dev->cpu_kcycles_used);
1251 }
1252
1253 static struct fb_deferred_io dlfb_defio = {
1254         .delay          = 5,
1255         .deferred_io    = dlfb_dpy_deferred_io,
1256 };
1257
1258 #endif
1259
1260 /*
1261  * This is necessary before we can communicate with the display controller.
1262  */
1263 static int dlfb_select_std_channel(struct dlfb_data *dev)
1264 {
1265         int ret;
1266         u8 set_def_chn[] = {       0x57, 0xCD, 0xDC, 0xA7,
1267                                 0x1C, 0x88, 0x5E, 0x15,
1268                                 0x60, 0xFE, 0xC6, 0x97,
1269                                 0x16, 0x3D, 0x47, 0xF2  };
1270
1271         ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
1272                         NR_USB_REQUEST_CHANNEL,
1273                         (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
1274                         set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT);
1275         return ret;
1276 }
1277
1278
1279 static int dlfb_usb_probe(struct usb_interface *interface,
1280                         const struct usb_device_id *id)
1281 {
1282         struct usb_device *usbdev;
1283         struct dlfb_data *dev;
1284         struct fb_info *info;
1285         int videomemorysize;
1286         int i;
1287         unsigned char *videomemory;
1288         int retval = -ENOMEM;
1289         struct fb_var_screeninfo *var;
1290         int registered = 0;
1291         u16 *pix_framebuffer;
1292
1293         /* usb initialization */
1294
1295         usbdev = interface_to_usbdev(interface);
1296
1297         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1298         if (dev == NULL) {
1299                 err("dlfb_usb_probe: failed alloc of dev struct\n");
1300                 goto error;
1301         }
1302
1303         /* we need to wait for both usb and fbdev to spin down on disconnect */
1304         kref_init(&dev->kref); /* matching kref_put in usb .disconnect fn */
1305         kref_get(&dev->kref); /* matching kref_put in .fb_destroy function*/
1306
1307         dev->udev = usbdev;
1308         dev->gdev = &usbdev->dev; /* our generic struct device * */
1309         usb_set_intfdata(interface, dev);
1310
1311         if (!dlfb_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
1312                 retval = -ENOMEM;
1313                 dl_err("dlfb_alloc_urb_list failed\n");
1314                 goto error;
1315         }
1316
1317         mutex_init(&dev->fb_open_lock);
1318
1319         /* We don't register a new USB class. Our client interface is fbdev */
1320
1321         /* allocates framebuffer driver structure, not framebuffer memory */
1322         info = framebuffer_alloc(0, &usbdev->dev);
1323         if (!info) {
1324                 retval = -ENOMEM;
1325                 dl_err("framebuffer_alloc failed\n");
1326                 goto error;
1327         }
1328         dev->info = info;
1329         info->par = dev;
1330         info->pseudo_palette = dev->pseudo_palette;
1331         info->fbops = &dlfb_ops;
1332
1333         var = &info->var;
1334
1335         /* TODO set limit based on actual SKU detection */
1336         dev->sku_pixel_limit = 2048 * 1152;
1337
1338         INIT_LIST_HEAD(&info->modelist);
1339         dlfb_parse_edid(dev, var, info);
1340
1341         /*
1342          * ok, now that we've got the size info, we can alloc our framebuffer.
1343          */
1344         info->fix = dlfb_fix;
1345         info->fix.line_length = var->xres * (var->bits_per_pixel / 8);
1346         videomemorysize = info->fix.line_length * var->yres;
1347
1348         /*
1349          * The big chunk of system memory we use as a virtual framebuffer.
1350          * TODO: Handle fbcon cursor code calling blit in interrupt context
1351          */
1352         videomemory = vmalloc(videomemorysize);
1353         if (!videomemory) {
1354                 retval = -ENOMEM;
1355                 dl_err("Virtual framebuffer alloc failed\n");
1356                 goto error;
1357         }
1358
1359         info->screen_base = videomemory;
1360         info->fix.smem_len = PAGE_ALIGN(videomemorysize);
1361         info->fix.smem_start = (unsigned long) videomemory;
1362         info->flags = udlfb_info_flags;
1363
1364
1365         /*
1366          * Second framebuffer copy, mirroring the state of the framebuffer
1367          * on the physical USB device. We can function without this.
1368          * But with imperfect damage info we may end up sending pixels over USB
1369          * that were, in fact, unchanged -- wasting limited USB bandwidth
1370          */
1371         dev->backing_buffer = vmalloc(videomemorysize);
1372         if (!dev->backing_buffer)
1373                 dl_warn("No shadow/backing buffer allcoated\n");
1374         else
1375                 memset(dev->backing_buffer, 0, videomemorysize);
1376
1377         retval = fb_alloc_cmap(&info->cmap, 256, 0);
1378         if (retval < 0) {
1379                 dl_err("fb_alloc_cmap failed %x\n", retval);
1380                 goto error;
1381         }
1382
1383         /* ready to begin using device */
1384
1385 #ifdef CONFIG_FB_DEFERRED_IO
1386         atomic_set(&dev->use_defio, 1);
1387 #endif
1388         atomic_set(&dev->usb_active, 1);
1389         dlfb_select_std_channel(dev);
1390
1391         dlfb_ops_check_var(var, info);
1392         dlfb_ops_set_par(info);
1393
1394         /* paint greenscreen */
1395         pix_framebuffer = (u16 *) videomemory;
1396         for (i = 0; i < videomemorysize / 2; i++)
1397                 pix_framebuffer[i] = 0x37e6;
1398
1399         dlfb_handle_damage(dev, 0, 0, info->var.xres, info->var.yres,
1400                                 videomemory);
1401
1402         retval = register_framebuffer(info);
1403         if (retval < 0) {
1404                 dl_err("register_framebuffer failed %d\n", retval);
1405                 goto error;
1406         }
1407         registered = 1;
1408
1409         for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
1410                 device_create_file(info->dev, &fb_device_attrs[i]);
1411
1412         device_create_bin_file(info->dev, &edid_attr);
1413
1414         dl_err("DisplayLink USB device /dev/fb%d attached. %dx%d resolution."
1415                         " Using %dK framebuffer memory\n", info->node,
1416                         var->xres, var->yres,
1417                         ((dev->backing_buffer) ?
1418                         videomemorysize * 2 : videomemorysize) >> 10);
1419         return 0;
1420
1421 error:
1422         if (dev) {
1423                 if (registered) {
1424                         unregister_framebuffer(info);
1425                         dlfb_ops_destroy(info);
1426                 } else
1427                         kref_put(&dev->kref, dlfb_delete);
1428
1429                 if (dev->urbs.count > 0)
1430                         dlfb_free_urb_list(dev);
1431                 kref_put(&dev->kref, dlfb_delete); /* last ref from kref_init */
1432
1433                 /* dev has been deallocated. Do not dereference */
1434         }
1435
1436         return retval;
1437 }
1438
1439 static void dlfb_usb_disconnect(struct usb_interface *interface)
1440 {
1441         struct dlfb_data *dev;
1442         struct fb_info *info;
1443         int i;
1444
1445         dev = usb_get_intfdata(interface);
1446         info = dev->info;
1447
1448         /* when non-active we'll update virtual framebuffer, but no new urbs */
1449         atomic_set(&dev->usb_active, 0);
1450
1451         usb_set_intfdata(interface, NULL);
1452
1453         for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
1454                 device_remove_file(info->dev, &fb_device_attrs[i]);
1455
1456         device_remove_bin_file(info->dev, &edid_attr);
1457
1458         /* this function will wait for all in-flight urbs to complete */
1459         dlfb_free_urb_list(dev);
1460
1461         if (info) {
1462                 dl_notice("Detaching /dev/fb%d\n", info->node);
1463                 unregister_framebuffer(info);
1464                 dlfb_ops_destroy(info);
1465         }
1466
1467         /* release reference taken by kref_init in probe() */
1468         kref_put(&dev->kref, dlfb_delete);
1469
1470         /* consider dlfb_data freed */
1471
1472         return;
1473 }
1474
1475 static struct usb_driver dlfb_driver = {
1476         .name = "udlfb",
1477         .probe = dlfb_usb_probe,
1478         .disconnect = dlfb_usb_disconnect,
1479         .id_table = id_table,
1480 };
1481
1482 static int __init dlfb_module_init(void)
1483 {
1484         int res;
1485
1486         res = usb_register(&dlfb_driver);
1487         if (res)
1488                 err("usb_register failed. Error number %d", res);
1489
1490         printk(KERN_INFO "VMODES initialized\n");
1491
1492         return res;
1493 }
1494
1495 static void __exit dlfb_module_exit(void)
1496 {
1497         usb_deregister(&dlfb_driver);
1498 }
1499
1500 module_init(dlfb_module_init);
1501 module_exit(dlfb_module_exit);
1502
1503 static void dlfb_urb_completion(struct urb *urb)
1504 {
1505         struct urb_node *unode = urb->context;
1506         struct dlfb_data *dev = unode->dev;
1507         unsigned long flags;
1508
1509         /* sync/async unlink faults aren't errors */
1510         if (urb->status) {
1511                 if (!(urb->status == -ENOENT ||
1512                     urb->status == -ECONNRESET ||
1513                     urb->status == -ESHUTDOWN)) {
1514                         dl_err("%s - nonzero write bulk status received: %d\n",
1515                                 __func__, urb->status);
1516                         atomic_set(&dev->lost_pixels, 1);
1517                 }
1518         }
1519
1520         urb->transfer_buffer_length = dev->urbs.size; /* reset to actual */
1521
1522         spin_lock_irqsave(&dev->urbs.lock, flags);
1523         list_add_tail(&unode->entry, &dev->urbs.list);
1524         dev->urbs.available++;
1525         spin_unlock_irqrestore(&dev->urbs.lock, flags);
1526
1527         up(&dev->urbs.limit_sem);
1528 }
1529
1530 static void dlfb_free_urb_list(struct dlfb_data *dev)
1531 {
1532         int count = dev->urbs.count;
1533         struct list_head *node;
1534         struct urb_node *unode;
1535         struct urb *urb;
1536         int ret;
1537         unsigned long flags;
1538
1539         dl_notice("Waiting for completes and freeing all render urbs\n");
1540
1541         /* keep waiting and freeing, until we've got 'em all */
1542         while (count--) {
1543                 /* Timeout means a memory leak and/or fault */
1544                 ret = down_timeout(&dev->urbs.limit_sem, FREE_URB_TIMEOUT);
1545                 if (ret) {
1546                         BUG_ON(ret);
1547                         break;
1548                 }
1549                 spin_lock_irqsave(&dev->urbs.lock, flags);
1550
1551                 node = dev->urbs.list.next; /* have reserved one with sem */
1552                 list_del_init(node);
1553
1554                 spin_unlock_irqrestore(&dev->urbs.lock, flags);
1555
1556                 unode = list_entry(node, struct urb_node, entry);
1557                 urb = unode->urb;
1558
1559                 /* Free each separately allocated piece */
1560                 usb_free_coherent(urb->dev, dev->urbs.size,
1561                                   urb->transfer_buffer, urb->transfer_dma);
1562                 usb_free_urb(urb);
1563                 kfree(node);
1564         }
1565
1566         kref_put(&dev->kref, dlfb_delete);
1567
1568 }
1569
1570 static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size)
1571 {
1572         int i = 0;
1573         struct urb *urb;
1574         struct urb_node *unode;
1575         char *buf;
1576
1577         spin_lock_init(&dev->urbs.lock);
1578
1579         dev->urbs.size = size;
1580         INIT_LIST_HEAD(&dev->urbs.list);
1581
1582         while (i < count) {
1583                 unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL);
1584                 if (!unode)
1585                         break;
1586                 unode->dev = dev;
1587
1588                 urb = usb_alloc_urb(0, GFP_KERNEL);
1589                 if (!urb) {
1590                         kfree(unode);
1591                         break;
1592                 }
1593                 unode->urb = urb;
1594
1595                 buf = usb_alloc_coherent(dev->udev, MAX_TRANSFER, GFP_KERNEL,
1596                                          &urb->transfer_dma);
1597                 if (!buf) {
1598                         kfree(unode);
1599                         usb_free_urb(urb);
1600                         break;
1601                 }
1602
1603                 /* urb->transfer_buffer_length set to actual before submit */
1604                 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 1),
1605                         buf, size, dlfb_urb_completion, unode);
1606                 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1607
1608                 list_add_tail(&unode->entry, &dev->urbs.list);
1609
1610                 i++;
1611         }
1612
1613         sema_init(&dev->urbs.limit_sem, i);
1614         dev->urbs.count = i;
1615         dev->urbs.available = i;
1616
1617         kref_get(&dev->kref); /* released in free_render_urbs() */
1618
1619         dl_notice("allocated %d %d byte urbs\n", i, (int) size);
1620
1621         return i;
1622 }
1623
1624 static struct urb *dlfb_get_urb(struct dlfb_data *dev)
1625 {
1626         int ret = 0;
1627         struct list_head *entry;
1628         struct urb_node *unode;
1629         struct urb *urb = NULL;
1630         unsigned long flags;
1631
1632         /* Wait for an in-flight buffer to complete and get re-queued */
1633         ret = down_timeout(&dev->urbs.limit_sem, GET_URB_TIMEOUT);
1634         if (ret) {
1635                 atomic_set(&dev->lost_pixels, 1);
1636                 dl_err("wait for urb interrupted: %x\n", ret);
1637                 goto error;
1638         }
1639
1640         spin_lock_irqsave(&dev->urbs.lock, flags);
1641
1642         BUG_ON(list_empty(&dev->urbs.list)); /* reserved one with limit_sem */
1643         entry = dev->urbs.list.next;
1644         list_del_init(entry);
1645         dev->urbs.available--;
1646
1647         spin_unlock_irqrestore(&dev->urbs.lock, flags);
1648
1649         unode = list_entry(entry, struct urb_node, entry);
1650         urb = unode->urb;
1651
1652 error:
1653         return urb;
1654 }
1655
1656 static int dlfb_submit_urb(struct dlfb_data *dev, struct urb *urb, size_t len)
1657 {
1658         int ret;
1659
1660         BUG_ON(len > dev->urbs.size);
1661
1662         urb->transfer_buffer_length = len; /* set to actual payload len */
1663         ret = usb_submit_urb(urb, GFP_KERNEL);
1664         if (ret) {
1665                 dlfb_urb_completion(urb); /* because no one else will */
1666                 atomic_set(&dev->lost_pixels, 1);
1667                 dl_err("usb_submit_urb error %x\n", ret);
1668         }
1669         return ret;
1670 }
1671
1672 MODULE_AUTHOR("Roberto De Ioris <roberto@unbit.it>, "
1673               "Jaya Kumar <jayakumar.lkml@gmail.com>, "
1674               "Bernie Thompson <bernie@plugable.com>");
1675 MODULE_DESCRIPTION("DisplayLink kernel framebuffer driver");
1676 MODULE_LICENSE("GPL");
1677