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