Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
1
fork

Configure Feed

Select the types of activity you want to include in your feed.

at master 1990 lines 52 kB view raw
1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * udlfb.c -- Framebuffer driver for DisplayLink USB controller 4 * 5 * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it> 6 * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com> 7 * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com> 8 * 9 * Layout is based on skeletonfb by James Simmons and Geert Uytterhoeven, 10 * usb-skeleton by GregKH. 11 * 12 * Device-specific portions based on information from Displaylink, with work 13 * from Florian Echtler, Henrik Bjerregaard Pedersen, and others. 14 */ 15 16#include <linux/module.h> 17#include <linux/kernel.h> 18#include <linux/init.h> 19#include <linux/usb.h> 20#include <linux/uaccess.h> 21#include <linux/mm.h> 22#include <linux/fb.h> 23#include <linux/vmalloc.h> 24#include <linux/slab.h> 25#include <linux/delay.h> 26#include <linux/unaligned.h> 27#include <video/udlfb.h> 28#include "edid.h" 29 30#define OUT_EP_NUM 1 /* The endpoint number we will use */ 31 32static const struct fb_fix_screeninfo dlfb_fix = { 33 .id = "udlfb", 34 .type = FB_TYPE_PACKED_PIXELS, 35 .visual = FB_VISUAL_TRUECOLOR, 36 .xpanstep = 0, 37 .ypanstep = 0, 38 .ywrapstep = 0, 39 .accel = FB_ACCEL_NONE, 40}; 41 42static const u32 udlfb_info_flags = FBINFO_READS_FAST | 43 FBINFO_VIRTFB | 44 FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT | 45 FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR; 46 47/* 48 * There are many DisplayLink-based graphics products, all with unique PIDs. 49 * So we match on DisplayLink's VID + Vendor-Defined Interface Class (0xff) 50 * We also require a match on SubClass (0x00) and Protocol (0x00), 51 * which is compatible with all known USB 2.0 era graphics chips and firmware, 52 * but allows DisplayLink to increment those for any future incompatible chips 53 */ 54static const struct usb_device_id id_table[] = { 55 {.idVendor = 0x17e9, 56 .bInterfaceClass = 0xff, 57 .bInterfaceSubClass = 0x00, 58 .bInterfaceProtocol = 0x00, 59 .match_flags = USB_DEVICE_ID_MATCH_VENDOR | 60 USB_DEVICE_ID_MATCH_INT_CLASS | 61 USB_DEVICE_ID_MATCH_INT_SUBCLASS | 62 USB_DEVICE_ID_MATCH_INT_PROTOCOL, 63 }, 64 {}, 65}; 66MODULE_DEVICE_TABLE(usb, id_table); 67 68/* module options */ 69static bool console = true; /* Allow fbcon to open framebuffer */ 70static bool fb_defio = true; /* Detect mmap writes using page faults */ 71static bool shadow = true; /* Optionally disable shadow framebuffer */ 72static int pixel_limit; /* Optionally force a pixel resolution limit */ 73 74struct dlfb_deferred_free { 75 struct list_head list; 76 void *mem; 77}; 78 79static int dlfb_realloc_framebuffer(struct dlfb_data *dlfb, struct fb_info *info, u32 new_len); 80 81/* dlfb keeps a list of urbs for efficient bulk transfers */ 82static void dlfb_urb_completion(struct urb *urb); 83static struct urb *dlfb_get_urb(struct dlfb_data *dlfb); 84static int dlfb_submit_urb(struct dlfb_data *dlfb, struct urb * urb, size_t len); 85static int dlfb_alloc_urb_list(struct dlfb_data *dlfb, int count, size_t size); 86static void dlfb_free_urb_list(struct dlfb_data *dlfb); 87 88/* 89 * All DisplayLink bulk operations start with 0xAF, followed by specific code 90 * All operations are written to buffers which then later get sent to device 91 */ 92static char *dlfb_set_register(char *buf, u8 reg, u8 val) 93{ 94 *buf++ = 0xAF; 95 *buf++ = 0x20; 96 *buf++ = reg; 97 *buf++ = val; 98 return buf; 99} 100 101static char *dlfb_vidreg_lock(char *buf) 102{ 103 return dlfb_set_register(buf, 0xFF, 0x00); 104} 105 106static char *dlfb_vidreg_unlock(char *buf) 107{ 108 return dlfb_set_register(buf, 0xFF, 0xFF); 109} 110 111/* 112 * Map FB_BLANK_* to DisplayLink register 113 * DLReg FB_BLANK_* 114 * ----- ----------------------------- 115 * 0x00 FB_BLANK_UNBLANK (0) 116 * 0x01 FB_BLANK (1) 117 * 0x03 FB_BLANK_VSYNC_SUSPEND (2) 118 * 0x05 FB_BLANK_HSYNC_SUSPEND (3) 119 * 0x07 FB_BLANK_POWERDOWN (4) Note: requires modeset to come back 120 */ 121static char *dlfb_blanking(char *buf, int fb_blank) 122{ 123 u8 reg; 124 125 switch (fb_blank) { 126 case FB_BLANK_POWERDOWN: 127 reg = 0x07; 128 break; 129 case FB_BLANK_HSYNC_SUSPEND: 130 reg = 0x05; 131 break; 132 case FB_BLANK_VSYNC_SUSPEND: 133 reg = 0x03; 134 break; 135 case FB_BLANK_NORMAL: 136 reg = 0x01; 137 break; 138 default: 139 reg = 0x00; 140 } 141 142 buf = dlfb_set_register(buf, 0x1F, reg); 143 144 return buf; 145} 146 147static char *dlfb_set_color_depth(char *buf, u8 selection) 148{ 149 return dlfb_set_register(buf, 0x00, selection); 150} 151 152static char *dlfb_set_base16bpp(char *wrptr, u32 base) 153{ 154 /* the base pointer is 16 bits wide, 0x20 is hi byte. */ 155 wrptr = dlfb_set_register(wrptr, 0x20, base >> 16); 156 wrptr = dlfb_set_register(wrptr, 0x21, base >> 8); 157 return dlfb_set_register(wrptr, 0x22, base); 158} 159 160/* 161 * DisplayLink HW has separate 16bpp and 8bpp framebuffers. 162 * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer 163 */ 164static char *dlfb_set_base8bpp(char *wrptr, u32 base) 165{ 166 wrptr = dlfb_set_register(wrptr, 0x26, base >> 16); 167 wrptr = dlfb_set_register(wrptr, 0x27, base >> 8); 168 return dlfb_set_register(wrptr, 0x28, base); 169} 170 171static char *dlfb_set_register_16(char *wrptr, u8 reg, u16 value) 172{ 173 wrptr = dlfb_set_register(wrptr, reg, value >> 8); 174 return dlfb_set_register(wrptr, reg+1, value); 175} 176 177/* 178 * This is kind of weird because the controller takes some 179 * register values in a different byte order than other registers. 180 */ 181static char *dlfb_set_register_16be(char *wrptr, u8 reg, u16 value) 182{ 183 wrptr = dlfb_set_register(wrptr, reg, value); 184 return dlfb_set_register(wrptr, reg+1, value >> 8); 185} 186 187/* 188 * LFSR is linear feedback shift register. The reason we have this is 189 * because the display controller needs to minimize the clock depth of 190 * various counters used in the display path. So this code reverses the 191 * provided value into the lfsr16 value by counting backwards to get 192 * the value that needs to be set in the hardware comparator to get the 193 * same actual count. This makes sense once you read above a couple of 194 * times and think about it from a hardware perspective. 195 */ 196static u16 dlfb_lfsr16(u16 actual_count) 197{ 198 u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */ 199 200 while (actual_count--) { 201 lv = ((lv << 1) | 202 (((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1)) 203 & 0xFFFF; 204 } 205 206 return (u16) lv; 207} 208 209/* 210 * This does LFSR conversion on the value that is to be written. 211 * See LFSR explanation above for more detail. 212 */ 213static char *dlfb_set_register_lfsr16(char *wrptr, u8 reg, u16 value) 214{ 215 return dlfb_set_register_16(wrptr, reg, dlfb_lfsr16(value)); 216} 217 218/* 219 * This takes a standard fbdev screeninfo struct and all of its monitor mode 220 * details and converts them into the DisplayLink equivalent register commands. 221 */ 222static char *dlfb_set_vid_cmds(char *wrptr, struct fb_var_screeninfo *var) 223{ 224 u16 xds, yds; 225 u16 xde, yde; 226 u16 yec; 227 228 /* x display start */ 229 xds = var->left_margin + var->hsync_len; 230 wrptr = dlfb_set_register_lfsr16(wrptr, 0x01, xds); 231 /* x display end */ 232 xde = xds + var->xres; 233 wrptr = dlfb_set_register_lfsr16(wrptr, 0x03, xde); 234 235 /* y display start */ 236 yds = var->upper_margin + var->vsync_len; 237 wrptr = dlfb_set_register_lfsr16(wrptr, 0x05, yds); 238 /* y display end */ 239 yde = yds + var->yres; 240 wrptr = dlfb_set_register_lfsr16(wrptr, 0x07, yde); 241 242 /* x end count is active + blanking - 1 */ 243 wrptr = dlfb_set_register_lfsr16(wrptr, 0x09, 244 xde + var->right_margin - 1); 245 246 /* libdlo hardcodes hsync start to 1 */ 247 wrptr = dlfb_set_register_lfsr16(wrptr, 0x0B, 1); 248 249 /* hsync end is width of sync pulse + 1 */ 250 wrptr = dlfb_set_register_lfsr16(wrptr, 0x0D, var->hsync_len + 1); 251 252 /* hpixels is active pixels */ 253 wrptr = dlfb_set_register_16(wrptr, 0x0F, var->xres); 254 255 /* yendcount is vertical active + vertical blanking */ 256 yec = var->yres + var->upper_margin + var->lower_margin + 257 var->vsync_len; 258 wrptr = dlfb_set_register_lfsr16(wrptr, 0x11, yec); 259 260 /* libdlo hardcodes vsync start to 0 */ 261 wrptr = dlfb_set_register_lfsr16(wrptr, 0x13, 0); 262 263 /* vsync end is width of vsync pulse */ 264 wrptr = dlfb_set_register_lfsr16(wrptr, 0x15, var->vsync_len); 265 266 /* vpixels is active pixels */ 267 wrptr = dlfb_set_register_16(wrptr, 0x17, var->yres); 268 269 /* convert picoseconds to 5kHz multiple for pclk5k = x * 1E12/5k */ 270 wrptr = dlfb_set_register_16be(wrptr, 0x1B, 271 200*1000*1000/var->pixclock); 272 273 return wrptr; 274} 275 276/* 277 * This takes a standard fbdev screeninfo struct that was fetched or prepared 278 * and then generates the appropriate command sequence that then drives the 279 * display controller. 280 */ 281static int dlfb_set_video_mode(struct dlfb_data *dlfb, 282 struct fb_var_screeninfo *var) 283{ 284 char *buf; 285 char *wrptr; 286 int retval; 287 int writesize; 288 struct urb *urb; 289 290 if (!atomic_read(&dlfb->usb_active)) 291 return -EPERM; 292 293 urb = dlfb_get_urb(dlfb); 294 if (!urb) 295 return -ENOMEM; 296 297 buf = (char *) urb->transfer_buffer; 298 299 /* 300 * This first section has to do with setting the base address on the 301 * controller * associated with the display. There are 2 base 302 * pointers, currently, we only * use the 16 bpp segment. 303 */ 304 wrptr = dlfb_vidreg_lock(buf); 305 wrptr = dlfb_set_color_depth(wrptr, 0x00); 306 /* set base for 16bpp segment to 0 */ 307 wrptr = dlfb_set_base16bpp(wrptr, 0); 308 /* set base for 8bpp segment to end of fb */ 309 wrptr = dlfb_set_base8bpp(wrptr, dlfb->info->fix.smem_len); 310 311 wrptr = dlfb_set_vid_cmds(wrptr, var); 312 wrptr = dlfb_blanking(wrptr, FB_BLANK_UNBLANK); 313 wrptr = dlfb_vidreg_unlock(wrptr); 314 315 writesize = wrptr - buf; 316 317 retval = dlfb_submit_urb(dlfb, urb, writesize); 318 319 dlfb->blank_mode = FB_BLANK_UNBLANK; 320 321 return retval; 322} 323 324static void dlfb_vm_open(struct vm_area_struct *vma) 325{ 326 struct dlfb_data *dlfb = vma->vm_private_data; 327 328 atomic_inc(&dlfb->mmap_count); 329} 330 331static void dlfb_vm_close(struct vm_area_struct *vma) 332{ 333 struct dlfb_data *dlfb = vma->vm_private_data; 334 335 atomic_dec(&dlfb->mmap_count); 336} 337 338static const struct vm_operations_struct dlfb_vm_ops = { 339 .open = dlfb_vm_open, 340 .close = dlfb_vm_close, 341}; 342 343static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma) 344{ 345 unsigned long start = vma->vm_start; 346 unsigned long size = vma->vm_end - vma->vm_start; 347 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; 348 unsigned long page, pos; 349 struct dlfb_data *dlfb = info->par; 350 351 if (info->fbdefio) 352 return fb_deferred_io_mmap(info, vma); 353 354 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); 355 356 if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) 357 return -EINVAL; 358 if (size > info->fix.smem_len) 359 return -EINVAL; 360 if (offset > info->fix.smem_len - size) 361 return -EINVAL; 362 363 pos = (unsigned long)info->fix.smem_start + offset; 364 365 dev_dbg(info->dev, "mmap() framebuffer addr:%lu size:%lu\n", 366 pos, size); 367 368 while (size > 0) { 369 page = vmalloc_to_pfn((void *)pos); 370 if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) 371 return -EAGAIN; 372 373 start += PAGE_SIZE; 374 pos += PAGE_SIZE; 375 if (size > PAGE_SIZE) 376 size -= PAGE_SIZE; 377 else 378 size = 0; 379 } 380 381 vma->vm_ops = &dlfb_vm_ops; 382 vma->vm_private_data = dlfb; 383 atomic_inc(&dlfb->mmap_count); 384 return 0; 385} 386 387/* 388 * Trims identical data from front and back of line 389 * Sets new front buffer address and width 390 * And returns byte count of identical pixels 391 * Assumes CPU natural alignment (unsigned long) 392 * for back and front buffer ptrs and width 393 */ 394static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes) 395{ 396 int j, k; 397 const unsigned long *back = (const unsigned long *) bback; 398 const unsigned long *front = (const unsigned long *) *bfront; 399 const int width = *width_bytes / sizeof(unsigned long); 400 int identical; 401 int start = width; 402 int end = width; 403 404 for (j = 0; j < width; j++) { 405 if (back[j] != front[j]) { 406 start = j; 407 break; 408 } 409 } 410 411 for (k = width - 1; k > j; k--) { 412 if (back[k] != front[k]) { 413 end = k+1; 414 break; 415 } 416 } 417 418 identical = start + (width - end); 419 *bfront = (u8 *) &front[start]; 420 *width_bytes = (end - start) * sizeof(unsigned long); 421 422 return identical * sizeof(unsigned long); 423} 424 425/* 426 * Render a command stream for an encoded horizontal line segment of pixels. 427 * 428 * A command buffer holds several commands. 429 * It always begins with a fresh command header 430 * (the protocol doesn't require this, but we enforce it to allow 431 * multiple buffers to be potentially encoded and sent in parallel). 432 * A single command encodes one contiguous horizontal line of pixels 433 * 434 * The function relies on the client to do all allocation, so that 435 * rendering can be done directly to output buffers (e.g. USB URBs). 436 * The function fills the supplied command buffer, providing information 437 * on where it left off, so the client may call in again with additional 438 * buffers if the line will take several buffers to complete. 439 * 440 * A single command can transmit a maximum of 256 pixels, 441 * regardless of the compression ratio (protocol design limit). 442 * To the hardware, 0 for a size byte means 256 443 * 444 * Rather than 256 pixel commands which are either rl or raw encoded, 445 * the rlx command simply assumes alternating raw and rl spans within one cmd. 446 * This has a slightly larger header overhead, but produces more even results. 447 * It also processes all data (read and write) in a single pass. 448 * Performance benchmarks of common cases show it having just slightly better 449 * compression than 256 pixel raw or rle commands, with similar CPU consumpion. 450 * But for very rl friendly data, will compress not quite as well. 451 */ 452static void dlfb_compress_hline( 453 const uint16_t **pixel_start_ptr, 454 const uint16_t *const pixel_end, 455 uint32_t *device_address_ptr, 456 uint8_t **command_buffer_ptr, 457 const uint8_t *const cmd_buffer_end, 458 unsigned long back_buffer_offset, 459 int *ident_ptr) 460{ 461 const uint16_t *pixel = *pixel_start_ptr; 462 uint32_t dev_addr = *device_address_ptr; 463 uint8_t *cmd = *command_buffer_ptr; 464 465 while ((pixel_end > pixel) && 466 (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) { 467 uint8_t *raw_pixels_count_byte = NULL; 468 uint8_t *cmd_pixels_count_byte = NULL; 469 const uint16_t *raw_pixel_start = NULL; 470 const uint16_t *cmd_pixel_start, *cmd_pixel_end = NULL; 471 472 if (back_buffer_offset && 473 *pixel == *(u16 *)((u8 *)pixel + back_buffer_offset)) { 474 pixel++; 475 dev_addr += BPP; 476 (*ident_ptr)++; 477 continue; 478 } 479 480 *cmd++ = 0xAF; 481 *cmd++ = 0x6B; 482 *cmd++ = dev_addr >> 16; 483 *cmd++ = dev_addr >> 8; 484 *cmd++ = dev_addr; 485 486 cmd_pixels_count_byte = cmd++; /* we'll know this later */ 487 cmd_pixel_start = pixel; 488 489 raw_pixels_count_byte = cmd++; /* we'll know this later */ 490 raw_pixel_start = pixel; 491 492 cmd_pixel_end = pixel + min3(MAX_CMD_PIXELS + 1UL, 493 (unsigned long)(pixel_end - pixel), 494 (unsigned long)(cmd_buffer_end - 1 - cmd) / BPP); 495 496 if (back_buffer_offset) { 497 /* note: the framebuffer may change under us, so we must test for underflow */ 498 while (cmd_pixel_end - 1 > pixel && 499 *(cmd_pixel_end - 1) == *(u16 *)((u8 *)(cmd_pixel_end - 1) + back_buffer_offset)) 500 cmd_pixel_end--; 501 } 502 503 while (pixel < cmd_pixel_end) { 504 const uint16_t * const repeating_pixel = pixel; 505 u16 pixel_value = *pixel; 506 507 put_unaligned_be16(pixel_value, cmd); 508 if (back_buffer_offset) 509 *(u16 *)((u8 *)pixel + back_buffer_offset) = pixel_value; 510 cmd += 2; 511 pixel++; 512 513 if (unlikely((pixel < cmd_pixel_end) && 514 (*pixel == pixel_value))) { 515 /* go back and fill in raw pixel count */ 516 *raw_pixels_count_byte = ((repeating_pixel - 517 raw_pixel_start) + 1) & 0xFF; 518 519 do { 520 if (back_buffer_offset) 521 *(u16 *)((u8 *)pixel + back_buffer_offset) = pixel_value; 522 pixel++; 523 } while ((pixel < cmd_pixel_end) && 524 (*pixel == pixel_value)); 525 526 /* immediately after raw data is repeat byte */ 527 *cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF; 528 529 /* Then start another raw pixel span */ 530 raw_pixel_start = pixel; 531 raw_pixels_count_byte = cmd++; 532 } 533 } 534 535 if (pixel > raw_pixel_start) { 536 /* finalize last RAW span */ 537 *raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF; 538 } else { 539 /* undo unused byte */ 540 cmd--; 541 } 542 543 *cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF; 544 dev_addr += (u8 *)pixel - (u8 *)cmd_pixel_start; 545 } 546 547 if (cmd_buffer_end - MIN_RLX_CMD_BYTES <= cmd) { 548 /* Fill leftover bytes with no-ops */ 549 if (cmd_buffer_end > cmd) 550 memset(cmd, 0xAF, cmd_buffer_end - cmd); 551 cmd = (uint8_t *) cmd_buffer_end; 552 } 553 554 *command_buffer_ptr = cmd; 555 *pixel_start_ptr = pixel; 556 *device_address_ptr = dev_addr; 557} 558 559/* 560 * There are 3 copies of every pixel: The front buffer that the fbdev 561 * client renders to, the actual framebuffer across the USB bus in hardware 562 * (that we can only write to, slowly, and can never read), and (optionally) 563 * our shadow copy that tracks what's been sent to that hardware buffer. 564 */ 565static int dlfb_render_hline(struct dlfb_data *dlfb, struct urb **urb_ptr, 566 const char *front, char **urb_buf_ptr, 567 u32 byte_offset, u32 byte_width, 568 int *ident_ptr, int *sent_ptr) 569{ 570 const u8 *line_start, *line_end, *next_pixel; 571 u32 dev_addr = dlfb->base16 + byte_offset; 572 struct urb *urb = *urb_ptr; 573 u8 *cmd = *urb_buf_ptr; 574 u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length; 575 unsigned long back_buffer_offset = 0; 576 577 line_start = (u8 *) (front + byte_offset); 578 next_pixel = line_start; 579 line_end = next_pixel + byte_width; 580 581 if (dlfb->backing_buffer) { 582 int offset; 583 const u8 *back_start = (u8 *) (dlfb->backing_buffer 584 + byte_offset); 585 586 back_buffer_offset = (unsigned long)back_start - (unsigned long)line_start; 587 588 *ident_ptr += dlfb_trim_hline(back_start, &next_pixel, 589 &byte_width); 590 591 offset = next_pixel - line_start; 592 line_end = next_pixel + byte_width; 593 dev_addr += offset; 594 back_start += offset; 595 line_start += offset; 596 } 597 598 while (next_pixel < line_end) { 599 600 dlfb_compress_hline((const uint16_t **) &next_pixel, 601 (const uint16_t *) line_end, &dev_addr, 602 (u8 **) &cmd, (u8 *) cmd_end, back_buffer_offset, 603 ident_ptr); 604 605 if (cmd >= cmd_end) { 606 int len = cmd - (u8 *) urb->transfer_buffer; 607 if (dlfb_submit_urb(dlfb, urb, len)) 608 return 1; /* lost pixels is set */ 609 *sent_ptr += len; 610 urb = dlfb_get_urb(dlfb); 611 if (!urb) 612 return 1; /* lost_pixels is set */ 613 *urb_ptr = urb; 614 cmd = urb->transfer_buffer; 615 cmd_end = &cmd[urb->transfer_buffer_length]; 616 } 617 } 618 619 *urb_buf_ptr = cmd; 620 621 return 0; 622} 623 624static int dlfb_handle_damage(struct dlfb_data *dlfb, int x, int y, int width, int height) 625{ 626 int i, ret; 627 char *cmd; 628 cycles_t start_cycles, end_cycles; 629 int bytes_sent = 0; 630 int bytes_identical = 0; 631 struct urb *urb; 632 int aligned_x; 633 634 start_cycles = get_cycles(); 635 636 mutex_lock(&dlfb->render_mutex); 637 638 aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long)); 639 width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long)); 640 x = aligned_x; 641 642 if ((width <= 0) || 643 (x + width > dlfb->info->var.xres) || 644 (y + height > dlfb->info->var.yres)) { 645 ret = -EINVAL; 646 goto unlock_ret; 647 } 648 649 if (!atomic_read(&dlfb->usb_active)) { 650 ret = 0; 651 goto unlock_ret; 652 } 653 654 urb = dlfb_get_urb(dlfb); 655 if (!urb) { 656 ret = 0; 657 goto unlock_ret; 658 } 659 cmd = urb->transfer_buffer; 660 661 for (i = y; i < y + height ; i++) { 662 const int line_offset = dlfb->info->fix.line_length * i; 663 const int byte_offset = line_offset + (x * BPP); 664 665 if (dlfb_render_hline(dlfb, &urb, 666 (char *) dlfb->info->fix.smem_start, 667 &cmd, byte_offset, width * BPP, 668 &bytes_identical, &bytes_sent)) 669 goto error; 670 } 671 672 if (cmd > (char *) urb->transfer_buffer) { 673 int len; 674 if (cmd < (char *) urb->transfer_buffer + urb->transfer_buffer_length) 675 *cmd++ = 0xAF; 676 /* Send partial buffer remaining before exiting */ 677 len = cmd - (char *) urb->transfer_buffer; 678 dlfb_submit_urb(dlfb, urb, len); 679 bytes_sent += len; 680 } else 681 dlfb_urb_completion(urb); 682 683error: 684 atomic_add(bytes_sent, &dlfb->bytes_sent); 685 atomic_add(bytes_identical, &dlfb->bytes_identical); 686 atomic_add(width*height*2, &dlfb->bytes_rendered); 687 end_cycles = get_cycles(); 688 atomic_add(((unsigned int) ((end_cycles - start_cycles) 689 >> 10)), /* Kcycles */ 690 &dlfb->cpu_kcycles_used); 691 692 ret = 0; 693 694unlock_ret: 695 mutex_unlock(&dlfb->render_mutex); 696 return ret; 697} 698 699static void dlfb_init_damage(struct dlfb_data *dlfb) 700{ 701 dlfb->damage_x = INT_MAX; 702 dlfb->damage_x2 = 0; 703 dlfb->damage_y = INT_MAX; 704 dlfb->damage_y2 = 0; 705} 706 707static void dlfb_damage_work(struct work_struct *w) 708{ 709 struct dlfb_data *dlfb = container_of(w, struct dlfb_data, damage_work); 710 int x, x2, y, y2; 711 712 spin_lock_irq(&dlfb->damage_lock); 713 x = dlfb->damage_x; 714 x2 = dlfb->damage_x2; 715 y = dlfb->damage_y; 716 y2 = dlfb->damage_y2; 717 dlfb_init_damage(dlfb); 718 spin_unlock_irq(&dlfb->damage_lock); 719 720 if (x < x2 && y < y2) 721 dlfb_handle_damage(dlfb, x, y, x2 - x, y2 - y); 722} 723 724static void dlfb_offload_damage(struct dlfb_data *dlfb, int x, int y, int width, int height) 725{ 726 unsigned long flags; 727 int x2 = x + width; 728 int y2 = y + height; 729 730 if (x >= x2 || y >= y2) 731 return; 732 733 spin_lock_irqsave(&dlfb->damage_lock, flags); 734 dlfb->damage_x = min(x, dlfb->damage_x); 735 dlfb->damage_x2 = max(x2, dlfb->damage_x2); 736 dlfb->damage_y = min(y, dlfb->damage_y); 737 dlfb->damage_y2 = max(y2, dlfb->damage_y2); 738 spin_unlock_irqrestore(&dlfb->damage_lock, flags); 739 740 schedule_work(&dlfb->damage_work); 741} 742 743/* 744 * NOTE: fb_defio.c is holding info->fbdefio.mutex 745 * Touching ANY framebuffer memory that triggers a page fault 746 * in fb_defio will cause a deadlock, when it also tries to 747 * grab the same mutex. 748 */ 749static void dlfb_dpy_deferred_io(struct fb_info *info, struct list_head *pagereflist) 750{ 751 struct fb_deferred_io_pageref *pageref; 752 struct dlfb_data *dlfb = info->par; 753 struct urb *urb; 754 char *cmd; 755 cycles_t start_cycles, end_cycles; 756 int bytes_sent = 0; 757 int bytes_identical = 0; 758 int bytes_rendered = 0; 759 760 mutex_lock(&dlfb->render_mutex); 761 762 if (!fb_defio) 763 goto unlock_ret; 764 765 if (!atomic_read(&dlfb->usb_active)) 766 goto unlock_ret; 767 768 start_cycles = get_cycles(); 769 770 urb = dlfb_get_urb(dlfb); 771 if (!urb) 772 goto unlock_ret; 773 774 cmd = urb->transfer_buffer; 775 776 /* walk the written page list and render each to device */ 777 list_for_each_entry(pageref, pagereflist, list) { 778 if (dlfb_render_hline(dlfb, &urb, (char *) info->fix.smem_start, 779 &cmd, pageref->offset, PAGE_SIZE, 780 &bytes_identical, &bytes_sent)) 781 goto error; 782 bytes_rendered += PAGE_SIZE; 783 } 784 785 if (cmd > (char *) urb->transfer_buffer) { 786 int len; 787 if (cmd < (char *) urb->transfer_buffer + urb->transfer_buffer_length) 788 *cmd++ = 0xAF; 789 /* Send partial buffer remaining before exiting */ 790 len = cmd - (char *) urb->transfer_buffer; 791 dlfb_submit_urb(dlfb, urb, len); 792 bytes_sent += len; 793 } else 794 dlfb_urb_completion(urb); 795 796error: 797 atomic_add(bytes_sent, &dlfb->bytes_sent); 798 atomic_add(bytes_identical, &dlfb->bytes_identical); 799 atomic_add(bytes_rendered, &dlfb->bytes_rendered); 800 end_cycles = get_cycles(); 801 atomic_add(((unsigned int) ((end_cycles - start_cycles) 802 >> 10)), /* Kcycles */ 803 &dlfb->cpu_kcycles_used); 804unlock_ret: 805 mutex_unlock(&dlfb->render_mutex); 806} 807 808static int dlfb_get_edid(struct dlfb_data *dlfb, char *edid, int len) 809{ 810 int i, ret; 811 char *rbuf; 812 813 rbuf = kmalloc(2, GFP_KERNEL); 814 if (!rbuf) 815 return 0; 816 817 for (i = 0; i < len; i++) { 818 ret = usb_control_msg(dlfb->udev, 819 usb_rcvctrlpipe(dlfb->udev, 0), 0x02, 820 (0x80 | (0x02 << 5)), i << 8, 0xA1, 821 rbuf, 2, USB_CTRL_GET_TIMEOUT); 822 if (ret < 2) { 823 dev_err(&dlfb->udev->dev, 824 "Read EDID byte %d failed: %d\n", i, ret); 825 i--; 826 break; 827 } 828 edid[i] = rbuf[1]; 829 } 830 831 kfree(rbuf); 832 833 return i; 834} 835 836static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd, 837 unsigned long arg) 838{ 839 840 struct dlfb_data *dlfb = info->par; 841 842 if (!atomic_read(&dlfb->usb_active)) 843 return 0; 844 845 /* TODO: Update X server to get this from sysfs instead */ 846 if (cmd == DLFB_IOCTL_RETURN_EDID) { 847 void __user *edid = (void __user *)arg; 848 if (copy_to_user(edid, dlfb->edid, dlfb->edid_size)) 849 return -EFAULT; 850 return 0; 851 } 852 853 /* TODO: Help propose a standard fb.h ioctl to report mmap damage */ 854 if (cmd == DLFB_IOCTL_REPORT_DAMAGE) { 855 struct dloarea area; 856 857 if (copy_from_user(&area, (void __user *)arg, 858 sizeof(struct dloarea))) 859 return -EFAULT; 860 861 /* 862 * If we have a damage-aware client, turn fb_defio "off" 863 * To avoid perf imact of unnecessary page fault handling. 864 * Done by resetting the delay for this fb_info to a very 865 * long period. Pages will become writable and stay that way. 866 * Reset to normal value when all clients have closed this fb. 867 */ 868 if (info->fbdefio) 869 info->fbdefio->delay = DL_DEFIO_WRITE_DISABLE; 870 871 if (area.x < 0) 872 area.x = 0; 873 874 if (area.x > info->var.xres) 875 area.x = info->var.xres; 876 877 if (area.y < 0) 878 area.y = 0; 879 880 if (area.y > info->var.yres) 881 area.y = info->var.yres; 882 883 dlfb_handle_damage(dlfb, area.x, area.y, area.w, area.h); 884 } 885 886 return 0; 887} 888 889/* taken from vesafb */ 890static int 891dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green, 892 unsigned blue, unsigned transp, struct fb_info *info) 893{ 894 int err = 0; 895 896 if (regno >= info->cmap.len) 897 return 1; 898 899 if (regno < 16) { 900 if (info->var.red.offset == 10) { 901 /* 1:5:5:5 */ 902 ((u32 *) (info->pseudo_palette))[regno] = 903 ((red & 0xf800) >> 1) | 904 ((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11); 905 } else { 906 /* 0:5:6:5 */ 907 ((u32 *) (info->pseudo_palette))[regno] = 908 ((red & 0xf800)) | 909 ((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11); 910 } 911 } 912 913 return err; 914} 915 916/* 917 * It's common for several clients to have framebuffer open simultaneously. 918 * e.g. both fbcon and X. Makes things interesting. 919 * Assumes caller is holding info->lock (for open and release at least) 920 */ 921static int dlfb_ops_open(struct fb_info *info, int user) 922{ 923 struct dlfb_data *dlfb = info->par; 924 925 /* 926 * fbcon aggressively connects to first framebuffer it finds, 927 * preventing other clients (X) from working properly. Usually 928 * not what the user wants. Fail by default with option to enable. 929 */ 930 if ((user == 0) && (!console)) 931 return -EBUSY; 932 933 /* If the USB device is gone, we don't accept new opens */ 934 if (dlfb->virtualized) 935 return -ENODEV; 936 937 dlfb->fb_count++; 938 939 if (fb_defio && (info->fbdefio == NULL)) { 940 /* enable defio at last moment if not disabled by client */ 941 942 struct fb_deferred_io *fbdefio; 943 944 fbdefio = kzalloc_obj(struct fb_deferred_io); 945 946 if (fbdefio) { 947 fbdefio->delay = DL_DEFIO_WRITE_DELAY; 948 fbdefio->sort_pagereflist = true; 949 fbdefio->deferred_io = dlfb_dpy_deferred_io; 950 } 951 952 info->fbdefio = fbdefio; 953 fb_deferred_io_init(info); 954 } 955 956 dev_dbg(info->dev, "open, user=%d fb_info=%p count=%d\n", 957 user, info, dlfb->fb_count); 958 959 return 0; 960} 961 962static void dlfb_ops_destroy(struct fb_info *info) 963{ 964 struct dlfb_data *dlfb = info->par; 965 966 cancel_work_sync(&dlfb->damage_work); 967 968 mutex_destroy(&dlfb->render_mutex); 969 970 if (info->cmap.len != 0) 971 fb_dealloc_cmap(&info->cmap); 972 if (info->monspecs.modedb) 973 fb_destroy_modedb(info->monspecs.modedb); 974 vfree(info->screen_buffer); 975 976 fb_destroy_modelist(&info->modelist); 977 978 while (!list_empty(&dlfb->deferred_free)) { 979 struct dlfb_deferred_free *d = list_entry(dlfb->deferred_free.next, struct dlfb_deferred_free, list); 980 list_del(&d->list); 981 vfree(d->mem); 982 kfree(d); 983 } 984 vfree(dlfb->backing_buffer); 985 kfree(dlfb->edid); 986 dlfb_free_urb_list(dlfb); 987 usb_put_dev(dlfb->udev); 988 kfree(dlfb); 989 990 /* Assume info structure is freed after this point */ 991 framebuffer_release(info); 992} 993 994/* 995 * Assumes caller is holding info->lock mutex (for open and release at least) 996 */ 997static int dlfb_ops_release(struct fb_info *info, int user) 998{ 999 struct dlfb_data *dlfb = info->par; 1000 1001 dlfb->fb_count--; 1002 1003 if ((dlfb->fb_count == 0) && (info->fbdefio)) { 1004 fb_deferred_io_cleanup(info); 1005 kfree(info->fbdefio); 1006 info->fbdefio = NULL; 1007 } 1008 1009 dev_dbg(info->dev, "release, user=%d count=%d\n", user, dlfb->fb_count); 1010 1011 return 0; 1012} 1013 1014/* 1015 * Check whether a video mode is supported by the DisplayLink chip 1016 * We start from monitor's modes, so don't need to filter that here 1017 */ 1018static int dlfb_is_valid_mode(struct fb_videomode *mode, struct dlfb_data *dlfb) 1019{ 1020 if (mode->xres * mode->yres > dlfb->sku_pixel_limit) 1021 return 0; 1022 1023 return 1; 1024} 1025 1026static void dlfb_var_color_format(struct fb_var_screeninfo *var) 1027{ 1028 const struct fb_bitfield red = { 11, 5, 0 }; 1029 const struct fb_bitfield green = { 5, 6, 0 }; 1030 const struct fb_bitfield blue = { 0, 5, 0 }; 1031 1032 var->bits_per_pixel = 16; 1033 var->red = red; 1034 var->green = green; 1035 var->blue = blue; 1036} 1037 1038static int dlfb_ops_check_var(struct fb_var_screeninfo *var, 1039 struct fb_info *info) 1040{ 1041 struct fb_videomode mode; 1042 struct dlfb_data *dlfb = info->par; 1043 1044 if (!var->pixclock) 1045 return -EINVAL; 1046 1047 /* set device-specific elements of var unrelated to mode */ 1048 dlfb_var_color_format(var); 1049 1050 fb_var_to_videomode(&mode, var); 1051 1052 if (!dlfb_is_valid_mode(&mode, dlfb)) 1053 return -EINVAL; 1054 1055 return 0; 1056} 1057 1058static int dlfb_ops_set_par(struct fb_info *info) 1059{ 1060 struct dlfb_data *dlfb = info->par; 1061 int result; 1062 u16 *pix_framebuffer; 1063 int i; 1064 struct fb_var_screeninfo fvs; 1065 u32 line_length = info->var.xres * (info->var.bits_per_pixel / 8); 1066 1067 /* clear the activate field because it causes spurious miscompares */ 1068 fvs = info->var; 1069 fvs.activate = 0; 1070 fvs.vmode &= ~FB_VMODE_SMOOTH_XPAN; 1071 1072 if (!memcmp(&dlfb->current_mode, &fvs, sizeof(struct fb_var_screeninfo))) 1073 return 0; 1074 1075 result = dlfb_realloc_framebuffer(dlfb, info, info->var.yres * line_length); 1076 if (result) 1077 return result; 1078 1079 result = dlfb_set_video_mode(dlfb, &info->var); 1080 1081 if (result) 1082 return result; 1083 1084 dlfb->current_mode = fvs; 1085 info->fix.line_length = line_length; 1086 1087 if (dlfb->fb_count == 0) { 1088 1089 /* paint greenscreen */ 1090 1091 pix_framebuffer = (u16 *)info->screen_buffer; 1092 for (i = 0; i < info->fix.smem_len / 2; i++) 1093 pix_framebuffer[i] = 0x37e6; 1094 } 1095 1096 dlfb_handle_damage(dlfb, 0, 0, info->var.xres, info->var.yres); 1097 1098 return 0; 1099} 1100 1101/* To fonzi the jukebox (e.g. make blanking changes take effect) */ 1102static char *dlfb_dummy_render(char *buf) 1103{ 1104 *buf++ = 0xAF; 1105 *buf++ = 0x6A; /* copy */ 1106 *buf++ = 0x00; /* from address*/ 1107 *buf++ = 0x00; 1108 *buf++ = 0x00; 1109 *buf++ = 0x01; /* one pixel */ 1110 *buf++ = 0x00; /* to address */ 1111 *buf++ = 0x00; 1112 *buf++ = 0x00; 1113 return buf; 1114} 1115 1116/* 1117 * In order to come back from full DPMS off, we need to set the mode again 1118 */ 1119static int dlfb_ops_blank(int blank_mode, struct fb_info *info) 1120{ 1121 struct dlfb_data *dlfb = info->par; 1122 char *bufptr; 1123 struct urb *urb; 1124 1125 dev_dbg(info->dev, "blank, mode %d --> %d\n", 1126 dlfb->blank_mode, blank_mode); 1127 1128 if ((dlfb->blank_mode == FB_BLANK_POWERDOWN) && 1129 (blank_mode != FB_BLANK_POWERDOWN)) { 1130 1131 /* returning from powerdown requires a fresh modeset */ 1132 dlfb_set_video_mode(dlfb, &info->var); 1133 } 1134 1135 urb = dlfb_get_urb(dlfb); 1136 if (!urb) 1137 return 0; 1138 1139 bufptr = (char *) urb->transfer_buffer; 1140 bufptr = dlfb_vidreg_lock(bufptr); 1141 bufptr = dlfb_blanking(bufptr, blank_mode); 1142 bufptr = dlfb_vidreg_unlock(bufptr); 1143 1144 /* seems like a render op is needed to have blank change take effect */ 1145 bufptr = dlfb_dummy_render(bufptr); 1146 1147 dlfb_submit_urb(dlfb, urb, bufptr - 1148 (char *) urb->transfer_buffer); 1149 1150 dlfb->blank_mode = blank_mode; 1151 1152 return 0; 1153} 1154 1155static void dlfb_ops_damage_range(struct fb_info *info, off_t off, size_t len) 1156{ 1157 struct dlfb_data *dlfb = info->par; 1158 int start = max((int)(off / info->fix.line_length), 0); 1159 int lines = min((u32)((len / info->fix.line_length) + 1), (u32)info->var.yres); 1160 1161 dlfb_handle_damage(dlfb, 0, start, info->var.xres, lines); 1162} 1163 1164static void dlfb_ops_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height) 1165{ 1166 struct dlfb_data *dlfb = info->par; 1167 1168 dlfb_offload_damage(dlfb, x, y, width, height); 1169} 1170 1171FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(dlfb_ops, 1172 dlfb_ops_damage_range, 1173 dlfb_ops_damage_area) 1174 1175static const struct fb_ops dlfb_ops = { 1176 .owner = THIS_MODULE, 1177 __FB_DEFAULT_DEFERRED_OPS_RDWR(dlfb_ops), 1178 .fb_setcolreg = dlfb_ops_setcolreg, 1179 __FB_DEFAULT_DEFERRED_OPS_DRAW(dlfb_ops), 1180 .fb_mmap = dlfb_ops_mmap, 1181 .fb_ioctl = dlfb_ops_ioctl, 1182 .fb_open = dlfb_ops_open, 1183 .fb_release = dlfb_ops_release, 1184 .fb_blank = dlfb_ops_blank, 1185 .fb_check_var = dlfb_ops_check_var, 1186 .fb_set_par = dlfb_ops_set_par, 1187 .fb_destroy = dlfb_ops_destroy, 1188}; 1189 1190 1191static void dlfb_deferred_vfree(struct dlfb_data *dlfb, void *mem) 1192{ 1193 struct dlfb_deferred_free *d = kmalloc_obj(struct dlfb_deferred_free); 1194 if (!d) 1195 return; 1196 d->mem = mem; 1197 list_add(&d->list, &dlfb->deferred_free); 1198} 1199 1200/* 1201 * Assumes &info->lock held by caller 1202 */ 1203static int dlfb_realloc_framebuffer(struct dlfb_data *dlfb, struct fb_info *info, u32 new_len) 1204{ 1205 u32 old_len = info->fix.smem_len; 1206 const void *old_fb = info->screen_buffer; 1207 unsigned char *new_fb; 1208 unsigned char *new_back = NULL; 1209 1210 new_len = PAGE_ALIGN(new_len); 1211 1212 if (new_len > old_len) { 1213 if (atomic_read(&dlfb->mmap_count) > 0) { 1214 dev_warn(info->dev, 1215 "refusing realloc: %d active mmaps\n", 1216 atomic_read(&dlfb->mmap_count)); 1217 return -EBUSY; 1218 } 1219 1220 /* 1221 * Alloc system memory for virtual framebuffer 1222 */ 1223 new_fb = vmalloc(new_len); 1224 if (!new_fb) { 1225 dev_err(info->dev, "Virtual framebuffer alloc failed\n"); 1226 return -ENOMEM; 1227 } 1228 memset(new_fb, 0xff, new_len); 1229 1230 if (info->screen_buffer) { 1231 memcpy(new_fb, old_fb, old_len); 1232 dlfb_deferred_vfree(dlfb, info->screen_buffer); 1233 } 1234 1235 info->screen_buffer = new_fb; 1236 info->fix.smem_len = new_len; 1237 info->fix.smem_start = (unsigned long) new_fb; 1238 info->flags = udlfb_info_flags; 1239 1240 /* 1241 * Second framebuffer copy to mirror the framebuffer state 1242 * on the physical USB device. We can function without this. 1243 * But with imperfect damage info we may send pixels over USB 1244 * that were, in fact, unchanged - wasting limited USB bandwidth 1245 */ 1246 if (shadow) 1247 new_back = vzalloc(new_len); 1248 if (!new_back) 1249 dev_info(info->dev, 1250 "No shadow/backing buffer allocated\n"); 1251 else { 1252 dlfb_deferred_vfree(dlfb, dlfb->backing_buffer); 1253 dlfb->backing_buffer = new_back; 1254 } 1255 } 1256 return 0; 1257} 1258 1259/* 1260 * 1) Get EDID from hw, or use sw default 1261 * 2) Parse into various fb_info structs 1262 * 3) Allocate virtual framebuffer memory to back highest res mode 1263 * 1264 * Parses EDID into three places used by various parts of fbdev: 1265 * fb_var_screeninfo contains the timing of the monitor's preferred mode 1266 * fb_info.monspecs is full parsed EDID info, including monspecs.modedb 1267 * fb_info.modelist is a linked list of all monitor & VESA modes which work 1268 * 1269 * If EDID is not readable/valid, then modelist is all VESA modes, 1270 * monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode 1271 * Returns 0 if successful 1272 */ 1273static int dlfb_setup_modes(struct dlfb_data *dlfb, 1274 struct fb_info *info, 1275 char *default_edid, size_t default_edid_size) 1276{ 1277 char *edid; 1278 int i, result = 0, tries = 3; 1279 struct device *dev = info->device; 1280 struct fb_videomode *mode; 1281 const struct fb_videomode *default_vmode = NULL; 1282 1283 if (info->dev) { 1284 /* only use mutex if info has been registered */ 1285 mutex_lock(&info->lock); 1286 /* parent device is used otherwise */ 1287 dev = info->dev; 1288 } 1289 1290 edid = kmalloc(EDID_LENGTH, GFP_KERNEL); 1291 if (!edid) { 1292 result = -ENOMEM; 1293 goto error; 1294 } 1295 1296 fb_destroy_modelist(&info->modelist); 1297 memset(&info->monspecs, 0, sizeof(info->monspecs)); 1298 1299 /* 1300 * Try to (re)read EDID from hardware first 1301 * EDID data may return, but not parse as valid 1302 * Try again a few times, in case of e.g. analog cable noise 1303 */ 1304 while (tries--) { 1305 1306 i = dlfb_get_edid(dlfb, edid, EDID_LENGTH); 1307 1308 if (i >= EDID_LENGTH) 1309 fb_edid_to_monspecs(edid, &info->monspecs); 1310 1311 if (info->monspecs.modedb_len > 0) { 1312 dlfb->edid = edid; 1313 dlfb->edid_size = i; 1314 break; 1315 } 1316 } 1317 1318 /* If that fails, use a previously returned EDID if available */ 1319 if (info->monspecs.modedb_len == 0) { 1320 dev_err(dev, "Unable to get valid EDID from device/display\n"); 1321 1322 if (dlfb->edid) { 1323 fb_edid_to_monspecs(dlfb->edid, &info->monspecs); 1324 if (info->monspecs.modedb_len > 0) 1325 dev_err(dev, "Using previously queried EDID\n"); 1326 } 1327 } 1328 1329 /* If that fails, use the default EDID we were handed */ 1330 if (info->monspecs.modedb_len == 0) { 1331 if (default_edid_size >= EDID_LENGTH) { 1332 fb_edid_to_monspecs(default_edid, &info->monspecs); 1333 if (info->monspecs.modedb_len > 0) { 1334 memcpy(edid, default_edid, default_edid_size); 1335 dlfb->edid = edid; 1336 dlfb->edid_size = default_edid_size; 1337 dev_err(dev, "Using default/backup EDID\n"); 1338 } 1339 } 1340 } 1341 1342 /* If we've got modes, let's pick a best default mode */ 1343 if (info->monspecs.modedb_len > 0) { 1344 1345 for (i = 0; i < info->monspecs.modedb_len; i++) { 1346 mode = &info->monspecs.modedb[i]; 1347 if (dlfb_is_valid_mode(mode, dlfb)) { 1348 fb_add_videomode(mode, &info->modelist); 1349 } else { 1350 dev_dbg(dev, "Specified mode %dx%d too big\n", 1351 mode->xres, mode->yres); 1352 if (i == 0) 1353 /* if we've removed top/best mode */ 1354 info->monspecs.misc 1355 &= ~FB_MISC_1ST_DETAIL; 1356 } 1357 } 1358 1359 default_vmode = fb_find_best_display(&info->monspecs, 1360 &info->modelist); 1361 } 1362 1363 /* If everything else has failed, fall back to safe default mode */ 1364 if (default_vmode == NULL) { 1365 1366 struct fb_videomode fb_vmode = {0}; 1367 1368 /* 1369 * Add the standard VESA modes to our modelist 1370 * Since we don't have EDID, there may be modes that 1371 * overspec monitor and/or are incorrect aspect ratio, etc. 1372 * But at least the user has a chance to choose 1373 */ 1374 for (i = 0; i < VESA_MODEDB_SIZE; i++) { 1375 mode = (struct fb_videomode *)&vesa_modes[i]; 1376 if (dlfb_is_valid_mode(mode, dlfb)) 1377 fb_add_videomode(mode, &info->modelist); 1378 else 1379 dev_dbg(dev, "VESA mode %dx%d too big\n", 1380 mode->xres, mode->yres); 1381 } 1382 1383 /* 1384 * default to resolution safe for projectors 1385 * (since they are most common case without EDID) 1386 */ 1387 fb_vmode.xres = 800; 1388 fb_vmode.yres = 600; 1389 fb_vmode.refresh = 60; 1390 default_vmode = fb_find_nearest_mode(&fb_vmode, 1391 &info->modelist); 1392 } 1393 1394 /* If we have good mode and no active clients*/ 1395 if ((default_vmode != NULL) && (dlfb->fb_count == 0)) { 1396 1397 fb_videomode_to_var(&info->var, default_vmode); 1398 dlfb_var_color_format(&info->var); 1399 1400 /* 1401 * with mode size info, we can now alloc our framebuffer. 1402 */ 1403 memcpy(&info->fix, &dlfb_fix, sizeof(dlfb_fix)); 1404 } else 1405 result = -EINVAL; 1406 1407error: 1408 if (edid && (dlfb->edid != edid)) 1409 kfree(edid); 1410 1411 if (info->dev) 1412 mutex_unlock(&info->lock); 1413 1414 return result; 1415} 1416 1417static ssize_t metrics_bytes_rendered_show(struct device *fbdev, 1418 struct device_attribute *a, char *buf) { 1419 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1420 struct dlfb_data *dlfb = fb_info->par; 1421 return sysfs_emit(buf, "%u\n", 1422 atomic_read(&dlfb->bytes_rendered)); 1423} 1424 1425static ssize_t metrics_bytes_identical_show(struct device *fbdev, 1426 struct device_attribute *a, char *buf) { 1427 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1428 struct dlfb_data *dlfb = fb_info->par; 1429 return sysfs_emit(buf, "%u\n", 1430 atomic_read(&dlfb->bytes_identical)); 1431} 1432 1433static ssize_t metrics_bytes_sent_show(struct device *fbdev, 1434 struct device_attribute *a, char *buf) { 1435 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1436 struct dlfb_data *dlfb = fb_info->par; 1437 return sysfs_emit(buf, "%u\n", 1438 atomic_read(&dlfb->bytes_sent)); 1439} 1440 1441static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev, 1442 struct device_attribute *a, char *buf) { 1443 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1444 struct dlfb_data *dlfb = fb_info->par; 1445 return sysfs_emit(buf, "%u\n", 1446 atomic_read(&dlfb->cpu_kcycles_used)); 1447} 1448 1449static ssize_t edid_show( 1450 struct file *filp, 1451 struct kobject *kobj, const struct bin_attribute *a, 1452 char *buf, loff_t off, size_t count) { 1453 struct device *fbdev = kobj_to_dev(kobj); 1454 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1455 struct dlfb_data *dlfb = fb_info->par; 1456 1457 if (dlfb->edid == NULL) 1458 return 0; 1459 1460 if ((off >= dlfb->edid_size) || (count > dlfb->edid_size)) 1461 return 0; 1462 1463 if (off + count > dlfb->edid_size) 1464 count = dlfb->edid_size - off; 1465 1466 memcpy(buf, dlfb->edid, count); 1467 1468 return count; 1469} 1470 1471static ssize_t edid_store( 1472 struct file *filp, 1473 struct kobject *kobj, const struct bin_attribute *a, 1474 char *src, loff_t src_off, size_t src_size) { 1475 struct device *fbdev = kobj_to_dev(kobj); 1476 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1477 struct dlfb_data *dlfb = fb_info->par; 1478 int ret; 1479 1480 /* We only support write of entire EDID at once, no offset*/ 1481 if ((src_size != EDID_LENGTH) || (src_off != 0)) 1482 return -EINVAL; 1483 1484 ret = dlfb_setup_modes(dlfb, fb_info, src, src_size); 1485 if (ret) 1486 return ret; 1487 1488 if (!dlfb->edid || memcmp(src, dlfb->edid, src_size)) 1489 return -EINVAL; 1490 1491 ret = dlfb_ops_set_par(fb_info); 1492 if (ret) 1493 return ret; 1494 1495 return src_size; 1496} 1497 1498static ssize_t metrics_reset_store(struct device *fbdev, 1499 struct device_attribute *attr, 1500 const char *buf, size_t count) 1501{ 1502 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1503 struct dlfb_data *dlfb = fb_info->par; 1504 1505 atomic_set(&dlfb->bytes_rendered, 0); 1506 atomic_set(&dlfb->bytes_identical, 0); 1507 atomic_set(&dlfb->bytes_sent, 0); 1508 atomic_set(&dlfb->cpu_kcycles_used, 0); 1509 1510 return count; 1511} 1512 1513static const struct bin_attribute edid_attr = { 1514 .attr.name = "edid", 1515 .attr.mode = 0666, 1516 .size = EDID_LENGTH, 1517 .read = edid_show, 1518 .write = edid_store 1519}; 1520 1521static const struct device_attribute fb_device_attrs[] = { 1522 __ATTR_RO(metrics_bytes_rendered), 1523 __ATTR_RO(metrics_bytes_identical), 1524 __ATTR_RO(metrics_bytes_sent), 1525 __ATTR_RO(metrics_cpu_kcycles_used), 1526 __ATTR(metrics_reset, S_IWUSR, NULL, metrics_reset_store), 1527}; 1528 1529/* 1530 * This is necessary before we can communicate with the display controller. 1531 */ 1532static int dlfb_select_std_channel(struct dlfb_data *dlfb) 1533{ 1534 int ret; 1535 static const u8 set_def_chn[] = { 1536 0x57, 0xCD, 0xDC, 0xA7, 1537 0x1C, 0x88, 0x5E, 0x15, 1538 0x60, 0xFE, 0xC6, 0x97, 1539 0x16, 0x3D, 0x47, 0xF2 }; 1540 1541 ret = usb_control_msg_send(dlfb->udev, 0, NR_USB_REQUEST_CHANNEL, 1542 (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0, 1543 &set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT, 1544 GFP_KERNEL); 1545 1546 return ret; 1547} 1548 1549static int dlfb_parse_vendor_descriptor(struct dlfb_data *dlfb, 1550 struct usb_interface *intf) 1551{ 1552 char *desc; 1553 char *buf; 1554 char *desc_end; 1555 int total_len; 1556 1557 buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL); 1558 if (!buf) 1559 return false; 1560 desc = buf; 1561 1562 total_len = usb_get_descriptor(interface_to_usbdev(intf), 1563 0x5f, /* vendor specific */ 1564 0, desc, MAX_VENDOR_DESCRIPTOR_SIZE); 1565 1566 /* if not found, look in configuration descriptor */ 1567 if (total_len < 0) { 1568 if (0 == usb_get_extra_descriptor(intf->cur_altsetting, 1569 0x5f, &desc)) 1570 total_len = (int) desc[0]; 1571 } 1572 1573 if (total_len > 5) { 1574 dev_info(&intf->dev, 1575 "vendor descriptor length: %d data: %11ph\n", 1576 total_len, desc); 1577 1578 if ((desc[0] != total_len) || /* descriptor length */ 1579 (desc[1] != 0x5f) || /* vendor descriptor type */ 1580 (desc[2] != 0x01) || /* version (2 bytes) */ 1581 (desc[3] != 0x00) || 1582 (desc[4] != total_len - 2)) /* length after type */ 1583 goto unrecognized; 1584 1585 desc_end = desc + total_len; 1586 desc += 5; /* the fixed header we've already parsed */ 1587 1588 while (desc < desc_end) { 1589 u8 length; 1590 u16 key; 1591 1592 key = *desc++; 1593 key |= (u16)*desc++ << 8; 1594 length = *desc++; 1595 1596 switch (key) { 1597 case 0x0200: { /* max_area */ 1598 u32 max_area = *desc++; 1599 max_area |= (u32)*desc++ << 8; 1600 max_area |= (u32)*desc++ << 16; 1601 max_area |= (u32)*desc++ << 24; 1602 dev_warn(&intf->dev, 1603 "DL chip limited to %d pixel modes\n", 1604 max_area); 1605 dlfb->sku_pixel_limit = max_area; 1606 break; 1607 } 1608 default: 1609 break; 1610 } 1611 desc += length; 1612 } 1613 } else { 1614 dev_info(&intf->dev, "vendor descriptor not available (%d)\n", 1615 total_len); 1616 } 1617 1618 goto success; 1619 1620unrecognized: 1621 /* allow udlfb to load for now even if firmware unrecognized */ 1622 dev_err(&intf->dev, "Unrecognized vendor firmware descriptor\n"); 1623 1624success: 1625 kfree(buf); 1626 return true; 1627} 1628 1629static int dlfb_usb_probe(struct usb_interface *intf, 1630 const struct usb_device_id *id) 1631{ 1632 int i; 1633 const struct device_attribute *attr; 1634 struct dlfb_data *dlfb; 1635 struct fb_info *info; 1636 int retval; 1637 struct usb_device *usbdev = interface_to_usbdev(intf); 1638 static u8 out_ep[] = {OUT_EP_NUM + USB_DIR_OUT, 0}; 1639 1640 /* usb initialization */ 1641 dlfb = kzalloc_obj(*dlfb); 1642 if (!dlfb) { 1643 dev_err(&intf->dev, "%s: failed to allocate dlfb\n", __func__); 1644 return -ENOMEM; 1645 } 1646 1647 INIT_LIST_HEAD(&dlfb->deferred_free); 1648 1649 dlfb->udev = usb_get_dev(usbdev); 1650 usb_set_intfdata(intf, dlfb); 1651 1652 if (!usb_check_bulk_endpoints(intf, out_ep)) { 1653 dev_err(&intf->dev, "Invalid DisplayLink device!\n"); 1654 retval = -EINVAL; 1655 goto error; 1656 } 1657 1658 dev_dbg(&intf->dev, "console enable=%d\n", console); 1659 dev_dbg(&intf->dev, "fb_defio enable=%d\n", fb_defio); 1660 dev_dbg(&intf->dev, "shadow enable=%d\n", shadow); 1661 1662 dlfb->sku_pixel_limit = 2048 * 1152; /* default to maximum */ 1663 1664 if (!dlfb_parse_vendor_descriptor(dlfb, intf)) { 1665 dev_err(&intf->dev, 1666 "firmware not recognized, incompatible device?\n"); 1667 retval = -ENODEV; 1668 goto error; 1669 } 1670 1671 if (pixel_limit) { 1672 dev_warn(&intf->dev, 1673 "DL chip limit of %d overridden to %d\n", 1674 dlfb->sku_pixel_limit, pixel_limit); 1675 dlfb->sku_pixel_limit = pixel_limit; 1676 } 1677 1678 1679 /* allocates framebuffer driver structure, not framebuffer memory */ 1680 info = framebuffer_alloc(0, &dlfb->udev->dev); 1681 if (!info) { 1682 retval = -ENOMEM; 1683 goto error; 1684 } 1685 1686 dlfb->info = info; 1687 info->par = dlfb; 1688 info->pseudo_palette = dlfb->pseudo_palette; 1689 dlfb->ops = dlfb_ops; 1690 info->fbops = &dlfb->ops; 1691 1692 mutex_init(&dlfb->render_mutex); 1693 dlfb_init_damage(dlfb); 1694 spin_lock_init(&dlfb->damage_lock); 1695 INIT_WORK(&dlfb->damage_work, dlfb_damage_work); 1696 1697 INIT_LIST_HEAD(&info->modelist); 1698 1699 if (!dlfb_alloc_urb_list(dlfb, WRITES_IN_FLIGHT, MAX_TRANSFER)) { 1700 retval = -ENOMEM; 1701 dev_err(&intf->dev, "unable to allocate urb list\n"); 1702 goto error; 1703 } 1704 1705 /* We don't register a new USB class. Our client interface is dlfbev */ 1706 1707 retval = fb_alloc_cmap(&info->cmap, 256, 0); 1708 if (retval < 0) { 1709 dev_err(info->device, "cmap allocation failed: %d\n", retval); 1710 goto error; 1711 } 1712 1713 retval = dlfb_setup_modes(dlfb, info, NULL, 0); 1714 if (retval != 0) { 1715 dev_err(info->device, 1716 "unable to find common mode for display and adapter\n"); 1717 goto error; 1718 } 1719 1720 /* ready to begin using device */ 1721 1722 atomic_set(&dlfb->usb_active, 1); 1723 dlfb_select_std_channel(dlfb); 1724 1725 dlfb_ops_check_var(&info->var, info); 1726 retval = dlfb_ops_set_par(info); 1727 if (retval) 1728 goto error; 1729 1730 retval = register_framebuffer(info); 1731 if (retval < 0) { 1732 dev_err(info->device, "unable to register framebuffer: %d\n", 1733 retval); 1734 goto error; 1735 } 1736 1737 for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) { 1738 attr = &fb_device_attrs[i]; 1739 retval = device_create_file(info->dev, attr); 1740 if (retval) 1741 dev_warn(info->device, 1742 "failed to create '%s' attribute: %d\n", 1743 attr->attr.name, retval); 1744 } 1745 1746 retval = device_create_bin_file(info->dev, &edid_attr); 1747 if (retval) 1748 dev_warn(info->device, "failed to create '%s' attribute: %d\n", 1749 edid_attr.attr.name, retval); 1750 1751 dev_info(info->device, 1752 "%s is DisplayLink USB device (%dx%d, %dK framebuffer memory)\n", 1753 dev_name(info->dev), info->var.xres, info->var.yres, 1754 ((dlfb->backing_buffer) ? 1755 info->fix.smem_len * 2 : info->fix.smem_len) >> 10); 1756 return 0; 1757 1758error: 1759 if (dlfb->info) { 1760 dlfb_ops_destroy(dlfb->info); 1761 } else { 1762 usb_put_dev(dlfb->udev); 1763 kfree(dlfb); 1764 } 1765 return retval; 1766} 1767 1768static void dlfb_usb_disconnect(struct usb_interface *intf) 1769{ 1770 struct dlfb_data *dlfb; 1771 struct fb_info *info; 1772 int i; 1773 1774 dlfb = usb_get_intfdata(intf); 1775 info = dlfb->info; 1776 1777 dev_dbg(&intf->dev, "USB disconnect starting\n"); 1778 1779 /* we virtualize until all fb clients release. Then we free */ 1780 dlfb->virtualized = true; 1781 1782 /* When non-active we'll update virtual framebuffer, but no new urbs */ 1783 atomic_set(&dlfb->usb_active, 0); 1784 1785 /* this function will wait for all in-flight urbs to complete */ 1786 dlfb_free_urb_list(dlfb); 1787 1788 /* remove udlfb's sysfs interfaces */ 1789 for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) 1790 device_remove_file(info->dev, &fb_device_attrs[i]); 1791 device_remove_bin_file(info->dev, &edid_attr); 1792 1793 unregister_framebuffer(info); 1794} 1795 1796static struct usb_driver dlfb_driver = { 1797 .name = "udlfb", 1798 .probe = dlfb_usb_probe, 1799 .disconnect = dlfb_usb_disconnect, 1800 .id_table = id_table, 1801}; 1802 1803module_usb_driver(dlfb_driver); 1804 1805static void dlfb_urb_completion(struct urb *urb) 1806{ 1807 struct urb_node *unode = urb->context; 1808 struct dlfb_data *dlfb = unode->dlfb; 1809 unsigned long flags; 1810 1811 switch (urb->status) { 1812 case 0: 1813 /* success */ 1814 break; 1815 case -ECONNRESET: 1816 case -ENOENT: 1817 case -ESHUTDOWN: 1818 /* sync/async unlink faults aren't errors */ 1819 break; 1820 default: 1821 dev_err(&dlfb->udev->dev, 1822 "%s - nonzero write bulk status received: %d\n", 1823 __func__, urb->status); 1824 atomic_set(&dlfb->lost_pixels, 1); 1825 break; 1826 } 1827 1828 urb->transfer_buffer_length = dlfb->urbs.size; /* reset to actual */ 1829 1830 spin_lock_irqsave(&dlfb->urbs.lock, flags); 1831 list_add_tail(&unode->entry, &dlfb->urbs.list); 1832 dlfb->urbs.available++; 1833 spin_unlock_irqrestore(&dlfb->urbs.lock, flags); 1834 1835 up(&dlfb->urbs.limit_sem); 1836} 1837 1838static void dlfb_free_urb_list(struct dlfb_data *dlfb) 1839{ 1840 int count = dlfb->urbs.count; 1841 struct list_head *node; 1842 struct urb_node *unode; 1843 struct urb *urb; 1844 1845 /* keep waiting and freeing, until we've got 'em all */ 1846 while (count--) { 1847 down(&dlfb->urbs.limit_sem); 1848 1849 spin_lock_irq(&dlfb->urbs.lock); 1850 1851 node = dlfb->urbs.list.next; /* have reserved one with sem */ 1852 list_del_init(node); 1853 1854 spin_unlock_irq(&dlfb->urbs.lock); 1855 1856 unode = list_entry(node, struct urb_node, entry); 1857 urb = unode->urb; 1858 1859 /* Free each separately allocated piece */ 1860 usb_free_coherent(urb->dev, dlfb->urbs.size, 1861 urb->transfer_buffer, urb->transfer_dma); 1862 usb_free_urb(urb); 1863 kfree(node); 1864 } 1865 1866 dlfb->urbs.count = 0; 1867} 1868 1869static int dlfb_alloc_urb_list(struct dlfb_data *dlfb, int count, size_t size) 1870{ 1871 struct urb *urb; 1872 struct urb_node *unode; 1873 char *buf; 1874 size_t wanted_size = count * size; 1875 1876 spin_lock_init(&dlfb->urbs.lock); 1877 1878retry: 1879 dlfb->urbs.size = size; 1880 INIT_LIST_HEAD(&dlfb->urbs.list); 1881 1882 sema_init(&dlfb->urbs.limit_sem, 0); 1883 dlfb->urbs.count = 0; 1884 dlfb->urbs.available = 0; 1885 1886 while (dlfb->urbs.count * size < wanted_size) { 1887 unode = kzalloc_obj(*unode); 1888 if (!unode) 1889 break; 1890 unode->dlfb = dlfb; 1891 1892 urb = usb_alloc_urb(0, GFP_KERNEL); 1893 if (!urb) { 1894 kfree(unode); 1895 break; 1896 } 1897 unode->urb = urb; 1898 1899 buf = usb_alloc_coherent(dlfb->udev, size, GFP_KERNEL, 1900 &urb->transfer_dma); 1901 if (!buf) { 1902 kfree(unode); 1903 usb_free_urb(urb); 1904 if (size > PAGE_SIZE) { 1905 size /= 2; 1906 dlfb_free_urb_list(dlfb); 1907 goto retry; 1908 } 1909 break; 1910 } 1911 1912 /* urb->transfer_buffer_length set to actual before submit */ 1913 usb_fill_bulk_urb(urb, dlfb->udev, 1914 usb_sndbulkpipe(dlfb->udev, OUT_EP_NUM), 1915 buf, size, dlfb_urb_completion, unode); 1916 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 1917 1918 list_add_tail(&unode->entry, &dlfb->urbs.list); 1919 1920 up(&dlfb->urbs.limit_sem); 1921 dlfb->urbs.count++; 1922 dlfb->urbs.available++; 1923 } 1924 1925 return dlfb->urbs.count; 1926} 1927 1928static struct urb *dlfb_get_urb(struct dlfb_data *dlfb) 1929{ 1930 int ret; 1931 struct list_head *entry; 1932 struct urb_node *unode; 1933 1934 /* Wait for an in-flight buffer to complete and get re-queued */ 1935 ret = down_timeout(&dlfb->urbs.limit_sem, GET_URB_TIMEOUT); 1936 if (ret) { 1937 atomic_set(&dlfb->lost_pixels, 1); 1938 dev_warn(&dlfb->udev->dev, 1939 "wait for urb interrupted: %d available: %d\n", 1940 ret, dlfb->urbs.available); 1941 return NULL; 1942 } 1943 1944 spin_lock_irq(&dlfb->urbs.lock); 1945 1946 BUG_ON(list_empty(&dlfb->urbs.list)); /* reserved one with limit_sem */ 1947 entry = dlfb->urbs.list.next; 1948 list_del_init(entry); 1949 dlfb->urbs.available--; 1950 1951 spin_unlock_irq(&dlfb->urbs.lock); 1952 1953 unode = list_entry(entry, struct urb_node, entry); 1954 return unode->urb; 1955} 1956 1957static int dlfb_submit_urb(struct dlfb_data *dlfb, struct urb *urb, size_t len) 1958{ 1959 int ret; 1960 1961 BUG_ON(len > dlfb->urbs.size); 1962 1963 urb->transfer_buffer_length = len; /* set to actual payload len */ 1964 ret = usb_submit_urb(urb, GFP_KERNEL); 1965 if (ret) { 1966 dlfb_urb_completion(urb); /* because no one else will */ 1967 atomic_set(&dlfb->lost_pixels, 1); 1968 dev_err(&dlfb->udev->dev, "submit urb error: %d\n", ret); 1969 } 1970 return ret; 1971} 1972 1973module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1974MODULE_PARM_DESC(console, "Allow fbcon to open framebuffer"); 1975 1976module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1977MODULE_PARM_DESC(fb_defio, "Page fault detection of mmap writes"); 1978 1979module_param(shadow, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1980MODULE_PARM_DESC(shadow, "Shadow vid mem. Disable to save mem but lose perf"); 1981 1982module_param(pixel_limit, int, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1983MODULE_PARM_DESC(pixel_limit, "Force limit on max mode (in x*y pixels)"); 1984 1985MODULE_AUTHOR("Roberto De Ioris <roberto@unbit.it>, " 1986 "Jaya Kumar <jayakumar.lkml@gmail.com>, " 1987 "Bernie Thompson <bernie@plugable.com>"); 1988MODULE_DESCRIPTION("DisplayLink kernel framebuffer driver"); 1989MODULE_LICENSE("GPL"); 1990