USB: convert some miscellanies drivers to use module_usb_driver()
[linux-2.6.git] / drivers / video / udlfb.c
1 /*
2  * udlfb.c -- Framebuffer driver for DisplayLink USB controller
3  *
4  * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
5  * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
6  * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License v2. See the file COPYING in the main directory of this archive for
10  * more details.
11  *
12  * Layout is based on skeletonfb by James Simmons and Geert Uytterhoeven,
13  * usb-skeleton by GregKH.
14  *
15  * Device-specific portions based on information from Displaylink, with work
16  * from Florian Echtler, Henrik Bjerregaard Pedersen, and others.
17  */
18
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20
21 #include <linux/module.h>
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/usb.h>
25 #include <linux/uaccess.h>
26 #include <linux/mm.h>
27 #include <linux/fb.h>
28 #include <linux/vmalloc.h>
29 #include <linux/slab.h>
30 #include <linux/prefetch.h>
31 #include <linux/delay.h>
32 #include <video/udlfb.h>
33 #include "edid.h"
34
35 static struct fb_fix_screeninfo dlfb_fix = {
36         .id =           "udlfb",
37         .type =         FB_TYPE_PACKED_PIXELS,
38         .visual =       FB_VISUAL_TRUECOLOR,
39         .xpanstep =     0,
40         .ypanstep =     0,
41         .ywrapstep =    0,
42         .accel =        FB_ACCEL_NONE,
43 };
44
45 static const u32 udlfb_info_flags = FBINFO_DEFAULT | FBINFO_READS_FAST |
46                 FBINFO_VIRTFB |
47                 FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT |
48                 FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR;
49
50 /*
51  * There are many DisplayLink-based graphics products, all with unique PIDs.
52  * So we match on DisplayLink's VID + Vendor-Defined Interface Class (0xff)
53  * We also require a match on SubClass (0x00) and Protocol (0x00),
54  * which is compatible with all known USB 2.0 era graphics chips and firmware,
55  * but allows DisplayLink to increment those for any future incompatible chips
56  */
57 static struct usb_device_id id_table[] = {
58         {.idVendor = 0x17e9,
59          .bInterfaceClass = 0xff,
60          .bInterfaceSubClass = 0x00,
61          .bInterfaceProtocol = 0x00,
62          .match_flags = USB_DEVICE_ID_MATCH_VENDOR |
63                 USB_DEVICE_ID_MATCH_INT_CLASS |
64                 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
65                 USB_DEVICE_ID_MATCH_INT_PROTOCOL,
66         },
67         {},
68 };
69 MODULE_DEVICE_TABLE(usb, id_table);
70
71 /* module options */
72 static int console = 1; /* Allow fbcon to open framebuffer */
73 static int fb_defio = 1;  /* Detect mmap writes using page faults */
74 static int shadow = 1; /* Optionally disable shadow framebuffer */
75
76 /* dlfb keeps a list of urbs for efficient bulk transfers */
77 static void dlfb_urb_completion(struct urb *urb);
78 static struct urb *dlfb_get_urb(struct dlfb_data *dev);
79 static int dlfb_submit_urb(struct dlfb_data *dev, struct urb * urb, size_t len);
80 static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size);
81 static void dlfb_free_urb_list(struct dlfb_data *dev);
82
83 /*
84  * All DisplayLink bulk operations start with 0xAF, followed by specific code
85  * All operations are written to buffers which then later get sent to device
86  */
87 static char *dlfb_set_register(char *buf, u8 reg, u8 val)
88 {
89         *buf++ = 0xAF;
90         *buf++ = 0x20;
91         *buf++ = reg;
92         *buf++ = val;
93         return buf;
94 }
95
96 static char *dlfb_vidreg_lock(char *buf)
97 {
98         return dlfb_set_register(buf, 0xFF, 0x00);
99 }
100
101 static char *dlfb_vidreg_unlock(char *buf)
102 {
103         return dlfb_set_register(buf, 0xFF, 0xFF);
104 }
105
106 /*
107  * Map FB_BLANK_* to DisplayLink register
108  * DLReg FB_BLANK_*
109  * ----- -----------------------------
110  *  0x00 FB_BLANK_UNBLANK (0)
111  *  0x01 FB_BLANK (1)
112  *  0x03 FB_BLANK_VSYNC_SUSPEND (2)
113  *  0x05 FB_BLANK_HSYNC_SUSPEND (3)
114  *  0x07 FB_BLANK_POWERDOWN (4) Note: requires modeset to come back
115  */
116 static char *dlfb_blanking(char *buf, int fb_blank)
117 {
118         u8 reg;
119
120         switch (fb_blank) {
121         case FB_BLANK_POWERDOWN:
122                 reg = 0x07;
123                 break;
124         case FB_BLANK_HSYNC_SUSPEND:
125                 reg = 0x05;
126                 break;
127         case FB_BLANK_VSYNC_SUSPEND:
128                 reg = 0x03;
129                 break;
130         case FB_BLANK_NORMAL:
131                 reg = 0x01;
132                 break;
133         default:
134                 reg = 0x00;
135         }
136
137         buf = dlfb_set_register(buf, 0x1F, reg);
138
139         return buf;
140 }
141
142 static char *dlfb_set_color_depth(char *buf, u8 selection)
143 {
144         return dlfb_set_register(buf, 0x00, selection);
145 }
146
147 static char *dlfb_set_base16bpp(char *wrptr, u32 base)
148 {
149         /* the base pointer is 16 bits wide, 0x20 is hi byte. */
150         wrptr = dlfb_set_register(wrptr, 0x20, base >> 16);
151         wrptr = dlfb_set_register(wrptr, 0x21, base >> 8);
152         return dlfb_set_register(wrptr, 0x22, base);
153 }
154
155 /*
156  * DisplayLink HW has separate 16bpp and 8bpp framebuffers.
157  * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer
158  */
159 static char *dlfb_set_base8bpp(char *wrptr, u32 base)
160 {
161         wrptr = dlfb_set_register(wrptr, 0x26, base >> 16);
162         wrptr = dlfb_set_register(wrptr, 0x27, base >> 8);
163         return dlfb_set_register(wrptr, 0x28, base);
164 }
165
166 static char *dlfb_set_register_16(char *wrptr, u8 reg, u16 value)
167 {
168         wrptr = dlfb_set_register(wrptr, reg, value >> 8);
169         return dlfb_set_register(wrptr, reg+1, value);
170 }
171
172 /*
173  * This is kind of weird because the controller takes some
174  * register values in a different byte order than other registers.
175  */
176 static char *dlfb_set_register_16be(char *wrptr, u8 reg, u16 value)
177 {
178         wrptr = dlfb_set_register(wrptr, reg, value);
179         return dlfb_set_register(wrptr, reg+1, value >> 8);
180 }
181
182 /*
183  * LFSR is linear feedback shift register. The reason we have this is
184  * because the display controller needs to minimize the clock depth of
185  * various counters used in the display path. So this code reverses the
186  * provided value into the lfsr16 value by counting backwards to get
187  * the value that needs to be set in the hardware comparator to get the
188  * same actual count. This makes sense once you read above a couple of
189  * times and think about it from a hardware perspective.
190  */
191 static u16 dlfb_lfsr16(u16 actual_count)
192 {
193         u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */
194
195         while (actual_count--) {
196                 lv =     ((lv << 1) |
197                         (((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1))
198                         & 0xFFFF;
199         }
200
201         return (u16) lv;
202 }
203
204 /*
205  * This does LFSR conversion on the value that is to be written.
206  * See LFSR explanation above for more detail.
207  */
208 static char *dlfb_set_register_lfsr16(char *wrptr, u8 reg, u16 value)
209 {
210         return dlfb_set_register_16(wrptr, reg, dlfb_lfsr16(value));
211 }
212
213 /*
214  * This takes a standard fbdev screeninfo struct and all of its monitor mode
215  * details and converts them into the DisplayLink equivalent register commands.
216  */
217 static char *dlfb_set_vid_cmds(char *wrptr, struct fb_var_screeninfo *var)
218 {
219         u16 xds, yds;
220         u16 xde, yde;
221         u16 yec;
222
223         /* x display start */
224         xds = var->left_margin + var->hsync_len;
225         wrptr = dlfb_set_register_lfsr16(wrptr, 0x01, xds);
226         /* x display end */
227         xde = xds + var->xres;
228         wrptr = dlfb_set_register_lfsr16(wrptr, 0x03, xde);
229
230         /* y display start */
231         yds = var->upper_margin + var->vsync_len;
232         wrptr = dlfb_set_register_lfsr16(wrptr, 0x05, yds);
233         /* y display end */
234         yde = yds + var->yres;
235         wrptr = dlfb_set_register_lfsr16(wrptr, 0x07, yde);
236
237         /* x end count is active + blanking - 1 */
238         wrptr = dlfb_set_register_lfsr16(wrptr, 0x09,
239                         xde + var->right_margin - 1);
240
241         /* libdlo hardcodes hsync start to 1 */
242         wrptr = dlfb_set_register_lfsr16(wrptr, 0x0B, 1);
243
244         /* hsync end is width of sync pulse + 1 */
245         wrptr = dlfb_set_register_lfsr16(wrptr, 0x0D, var->hsync_len + 1);
246
247         /* hpixels is active pixels */
248         wrptr = dlfb_set_register_16(wrptr, 0x0F, var->xres);
249
250         /* yendcount is vertical active + vertical blanking */
251         yec = var->yres + var->upper_margin + var->lower_margin +
252                         var->vsync_len;
253         wrptr = dlfb_set_register_lfsr16(wrptr, 0x11, yec);
254
255         /* libdlo hardcodes vsync start to 0 */
256         wrptr = dlfb_set_register_lfsr16(wrptr, 0x13, 0);
257
258         /* vsync end is width of vsync pulse */
259         wrptr = dlfb_set_register_lfsr16(wrptr, 0x15, var->vsync_len);
260
261         /* vpixels is active pixels */
262         wrptr = dlfb_set_register_16(wrptr, 0x17, var->yres);
263
264         /* convert picoseconds to 5kHz multiple for pclk5k = x * 1E12/5k */
265         wrptr = dlfb_set_register_16be(wrptr, 0x1B,
266                         200*1000*1000/var->pixclock);
267
268         return wrptr;
269 }
270
271 /*
272  * This takes a standard fbdev screeninfo struct that was fetched or prepared
273  * and then generates the appropriate command sequence that then drives the
274  * display controller.
275  */
276 static int dlfb_set_video_mode(struct dlfb_data *dev,
277                                 struct fb_var_screeninfo *var)
278 {
279         char *buf;
280         char *wrptr;
281         int retval = 0;
282         int writesize;
283         struct urb *urb;
284
285         if (!atomic_read(&dev->usb_active))
286                 return -EPERM;
287
288         urb = dlfb_get_urb(dev);
289         if (!urb)
290                 return -ENOMEM;
291
292         buf = (char *) urb->transfer_buffer;
293
294         /*
295         * This first section has to do with setting the base address on the
296         * controller * associated with the display. There are 2 base
297         * pointers, currently, we only * use the 16 bpp segment.
298         */
299         wrptr = dlfb_vidreg_lock(buf);
300         wrptr = dlfb_set_color_depth(wrptr, 0x00);
301         /* set base for 16bpp segment to 0 */
302         wrptr = dlfb_set_base16bpp(wrptr, 0);
303         /* set base for 8bpp segment to end of fb */
304         wrptr = dlfb_set_base8bpp(wrptr, dev->info->fix.smem_len);
305
306         wrptr = dlfb_set_vid_cmds(wrptr, var);
307         wrptr = dlfb_blanking(wrptr, FB_BLANK_UNBLANK);
308         wrptr = dlfb_vidreg_unlock(wrptr);
309
310         writesize = wrptr - buf;
311
312         retval = dlfb_submit_urb(dev, urb, writesize);
313
314         dev->blank_mode = FB_BLANK_UNBLANK;
315
316         return retval;
317 }
318
319 static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)
320 {
321         unsigned long start = vma->vm_start;
322         unsigned long size = vma->vm_end - vma->vm_start;
323         unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
324         unsigned long page, pos;
325
326         if (offset + size > info->fix.smem_len)
327                 return -EINVAL;
328
329         pos = (unsigned long)info->fix.smem_start + offset;
330
331         pr_notice("mmap() framebuffer addr:%lu size:%lu\n",
332                   pos, size);
333
334         while (size > 0) {
335                 page = vmalloc_to_pfn((void *)pos);
336                 if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))
337                         return -EAGAIN;
338
339                 start += PAGE_SIZE;
340                 pos += PAGE_SIZE;
341                 if (size > PAGE_SIZE)
342                         size -= PAGE_SIZE;
343                 else
344                         size = 0;
345         }
346
347         vma->vm_flags |= VM_RESERVED;   /* avoid to swap out this VMA */
348         return 0;
349 }
350
351 /*
352  * Trims identical data from front and back of line
353  * Sets new front buffer address and width
354  * And returns byte count of identical pixels
355  * Assumes CPU natural alignment (unsigned long)
356  * for back and front buffer ptrs and width
357  */
358 static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)
359 {
360         int j, k;
361         const unsigned long *back = (const unsigned long *) bback;
362         const unsigned long *front = (const unsigned long *) *bfront;
363         const int width = *width_bytes / sizeof(unsigned long);
364         int identical = width;
365         int start = width;
366         int end = width;
367
368         prefetch((void *) front);
369         prefetch((void *) back);
370
371         for (j = 0; j < width; j++) {
372                 if (back[j] != front[j]) {
373                         start = j;
374                         break;
375                 }
376         }
377
378         for (k = width - 1; k > j; k--) {
379                 if (back[k] != front[k]) {
380                         end = k+1;
381                         break;
382                 }
383         }
384
385         identical = start + (width - end);
386         *bfront = (u8 *) &front[start];
387         *width_bytes = (end - start) * sizeof(unsigned long);
388
389         return identical * sizeof(unsigned long);
390 }
391
392 /*
393  * Render a command stream for an encoded horizontal line segment of pixels.
394  *
395  * A command buffer holds several commands.
396  * It always begins with a fresh command header
397  * (the protocol doesn't require this, but we enforce it to allow
398  * multiple buffers to be potentially encoded and sent in parallel).
399  * A single command encodes one contiguous horizontal line of pixels
400  *
401  * The function relies on the client to do all allocation, so that
402  * rendering can be done directly to output buffers (e.g. USB URBs).
403  * The function fills the supplied command buffer, providing information
404  * on where it left off, so the client may call in again with additional
405  * buffers if the line will take several buffers to complete.
406  *
407  * A single command can transmit a maximum of 256 pixels,
408  * regardless of the compression ratio (protocol design limit).
409  * To the hardware, 0 for a size byte means 256
410  *
411  * Rather than 256 pixel commands which are either rl or raw encoded,
412  * the rlx command simply assumes alternating raw and rl spans within one cmd.
413  * This has a slightly larger header overhead, but produces more even results.
414  * It also processes all data (read and write) in a single pass.
415  * Performance benchmarks of common cases show it having just slightly better
416  * compression than 256 pixel raw or rle commands, with similar CPU consumpion.
417  * But for very rl friendly data, will compress not quite as well.
418  */
419 static void dlfb_compress_hline(
420         const uint16_t **pixel_start_ptr,
421         const uint16_t *const pixel_end,
422         uint32_t *device_address_ptr,
423         uint8_t **command_buffer_ptr,
424         const uint8_t *const cmd_buffer_end)
425 {
426         const uint16_t *pixel = *pixel_start_ptr;
427         uint32_t dev_addr  = *device_address_ptr;
428         uint8_t *cmd = *command_buffer_ptr;
429         const int bpp = 2;
430
431         while ((pixel_end > pixel) &&
432                (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) {
433                 uint8_t *raw_pixels_count_byte = 0;
434                 uint8_t *cmd_pixels_count_byte = 0;
435                 const uint16_t *raw_pixel_start = 0;
436                 const uint16_t *cmd_pixel_start, *cmd_pixel_end = 0;
437
438                 prefetchw((void *) cmd); /* pull in one cache line at least */
439
440                 *cmd++ = 0xAF;
441                 *cmd++ = 0x6B;
442                 *cmd++ = (uint8_t) ((dev_addr >> 16) & 0xFF);
443                 *cmd++ = (uint8_t) ((dev_addr >> 8) & 0xFF);
444                 *cmd++ = (uint8_t) ((dev_addr) & 0xFF);
445
446                 cmd_pixels_count_byte = cmd++; /*  we'll know this later */
447                 cmd_pixel_start = pixel;
448
449                 raw_pixels_count_byte = cmd++; /*  we'll know this later */
450                 raw_pixel_start = pixel;
451
452                 cmd_pixel_end = pixel + min(MAX_CMD_PIXELS + 1,
453                         min((int)(pixel_end - pixel),
454                             (int)(cmd_buffer_end - cmd) / bpp));
455
456                 prefetch_range((void *) pixel, (cmd_pixel_end - pixel) * bpp);
457
458                 while (pixel < cmd_pixel_end) {
459                         const uint16_t * const repeating_pixel = pixel;
460
461                         *(uint16_t *)cmd = cpu_to_be16p(pixel);
462                         cmd += 2;
463                         pixel++;
464
465                         if (unlikely((pixel < cmd_pixel_end) &&
466                                      (*pixel == *repeating_pixel))) {
467                                 /* go back and fill in raw pixel count */
468                                 *raw_pixels_count_byte = ((repeating_pixel -
469                                                 raw_pixel_start) + 1) & 0xFF;
470
471                                 while ((pixel < cmd_pixel_end)
472                                        && (*pixel == *repeating_pixel)) {
473                                         pixel++;
474                                 }
475
476                                 /* immediately after raw data is repeat byte */
477                                 *cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF;
478
479                                 /* Then start another raw pixel span */
480                                 raw_pixel_start = pixel;
481                                 raw_pixels_count_byte = cmd++;
482                         }
483                 }
484
485                 if (pixel > raw_pixel_start) {
486                         /* finalize last RAW span */
487                         *raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF;
488                 }
489
490                 *cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF;
491                 dev_addr += (pixel - cmd_pixel_start) * bpp;
492         }
493
494         if (cmd_buffer_end <= MIN_RLX_CMD_BYTES + cmd) {
495                 /* Fill leftover bytes with no-ops */
496                 if (cmd_buffer_end > cmd)
497                         memset(cmd, 0xAF, cmd_buffer_end - cmd);
498                 cmd = (uint8_t *) cmd_buffer_end;
499         }
500
501         *command_buffer_ptr = cmd;
502         *pixel_start_ptr = pixel;
503         *device_address_ptr = dev_addr;
504
505         return;
506 }
507
508 /*
509  * There are 3 copies of every pixel: The front buffer that the fbdev
510  * client renders to, the actual framebuffer across the USB bus in hardware
511  * (that we can only write to, slowly, and can never read), and (optionally)
512  * our shadow copy that tracks what's been sent to that hardware buffer.
513  */
514 static int dlfb_render_hline(struct dlfb_data *dev, struct urb **urb_ptr,
515                               const char *front, char **urb_buf_ptr,
516                               u32 byte_offset, u32 byte_width,
517                               int *ident_ptr, int *sent_ptr)
518 {
519         const u8 *line_start, *line_end, *next_pixel;
520         u32 dev_addr = dev->base16 + byte_offset;
521         struct urb *urb = *urb_ptr;
522         u8 *cmd = *urb_buf_ptr;
523         u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length;
524
525         line_start = (u8 *) (front + byte_offset);
526         next_pixel = line_start;
527         line_end = next_pixel + byte_width;
528
529         if (dev->backing_buffer) {
530                 int offset;
531                 const u8 *back_start = (u8 *) (dev->backing_buffer
532                                                 + byte_offset);
533
534                 *ident_ptr += dlfb_trim_hline(back_start, &next_pixel,
535                         &byte_width);
536
537                 offset = next_pixel - line_start;
538                 line_end = next_pixel + byte_width;
539                 dev_addr += offset;
540                 back_start += offset;
541                 line_start += offset;
542
543                 memcpy((char *)back_start, (char *) line_start,
544                        byte_width);
545         }
546
547         while (next_pixel < line_end) {
548
549                 dlfb_compress_hline((const uint16_t **) &next_pixel,
550                              (const uint16_t *) line_end, &dev_addr,
551                         (u8 **) &cmd, (u8 *) cmd_end);
552
553                 if (cmd >= cmd_end) {
554                         int len = cmd - (u8 *) urb->transfer_buffer;
555                         if (dlfb_submit_urb(dev, urb, len))
556                                 return 1; /* lost pixels is set */
557                         *sent_ptr += len;
558                         urb = dlfb_get_urb(dev);
559                         if (!urb)
560                                 return 1; /* lost_pixels is set */
561                         *urb_ptr = urb;
562                         cmd = urb->transfer_buffer;
563                         cmd_end = &cmd[urb->transfer_buffer_length];
564                 }
565         }
566
567         *urb_buf_ptr = cmd;
568
569         return 0;
570 }
571
572 int dlfb_handle_damage(struct dlfb_data *dev, int x, int y,
573                int width, int height, char *data)
574 {
575         int i, ret;
576         char *cmd;
577         cycles_t start_cycles, end_cycles;
578         int bytes_sent = 0;
579         int bytes_identical = 0;
580         struct urb *urb;
581         int aligned_x;
582
583         start_cycles = get_cycles();
584
585         aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long));
586         width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long));
587         x = aligned_x;
588
589         if ((width <= 0) ||
590             (x + width > dev->info->var.xres) ||
591             (y + height > dev->info->var.yres))
592                 return -EINVAL;
593
594         if (!atomic_read(&dev->usb_active))
595                 return 0;
596
597         urb = dlfb_get_urb(dev);
598         if (!urb)
599                 return 0;
600         cmd = urb->transfer_buffer;
601
602         for (i = y; i < y + height ; i++) {
603                 const int line_offset = dev->info->fix.line_length * i;
604                 const int byte_offset = line_offset + (x * BPP);
605
606                 if (dlfb_render_hline(dev, &urb,
607                                       (char *) dev->info->fix.smem_start,
608                                       &cmd, byte_offset, width * BPP,
609                                       &bytes_identical, &bytes_sent))
610                         goto error;
611         }
612
613         if (cmd > (char *) urb->transfer_buffer) {
614                 /* Send partial buffer remaining before exiting */
615                 int len = cmd - (char *) urb->transfer_buffer;
616                 ret = dlfb_submit_urb(dev, urb, len);
617                 bytes_sent += len;
618         } else
619                 dlfb_urb_completion(urb);
620
621 error:
622         atomic_add(bytes_sent, &dev->bytes_sent);
623         atomic_add(bytes_identical, &dev->bytes_identical);
624         atomic_add(width*height*2, &dev->bytes_rendered);
625         end_cycles = get_cycles();
626         atomic_add(((unsigned int) ((end_cycles - start_cycles)
627                     >> 10)), /* Kcycles */
628                    &dev->cpu_kcycles_used);
629
630         return 0;
631 }
632
633 /*
634  * Path triggered by usermode clients who write to filesystem
635  * e.g. cat filename > /dev/fb1
636  * Not used by X Windows or text-mode console. But useful for testing.
637  * Slow because of extra copy and we must assume all pixels dirty.
638  */
639 static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
640                           size_t count, loff_t *ppos)
641 {
642         ssize_t result;
643         struct dlfb_data *dev = info->par;
644         u32 offset = (u32) *ppos;
645
646         result = fb_sys_write(info, buf, count, ppos);
647
648         if (result > 0) {
649                 int start = max((int)(offset / info->fix.line_length) - 1, 0);
650                 int lines = min((u32)((result / info->fix.line_length) + 1),
651                                 (u32)info->var.yres);
652
653                 dlfb_handle_damage(dev, 0, start, info->var.xres,
654                         lines, info->screen_base);
655         }
656
657         return result;
658 }
659
660 /* hardware has native COPY command (see libdlo), but not worth it for fbcon */
661 static void dlfb_ops_copyarea(struct fb_info *info,
662                                 const struct fb_copyarea *area)
663 {
664
665         struct dlfb_data *dev = info->par;
666
667         sys_copyarea(info, area);
668
669         dlfb_handle_damage(dev, area->dx, area->dy,
670                         area->width, area->height, info->screen_base);
671 }
672
673 static void dlfb_ops_imageblit(struct fb_info *info,
674                                 const struct fb_image *image)
675 {
676         struct dlfb_data *dev = info->par;
677
678         sys_imageblit(info, image);
679
680         dlfb_handle_damage(dev, image->dx, image->dy,
681                         image->width, image->height, info->screen_base);
682 }
683
684 static void dlfb_ops_fillrect(struct fb_info *info,
685                           const struct fb_fillrect *rect)
686 {
687         struct dlfb_data *dev = info->par;
688
689         sys_fillrect(info, rect);
690
691         dlfb_handle_damage(dev, rect->dx, rect->dy, rect->width,
692                               rect->height, info->screen_base);
693 }
694
695 /*
696  * NOTE: fb_defio.c is holding info->fbdefio.mutex
697  *   Touching ANY framebuffer memory that triggers a page fault
698  *   in fb_defio will cause a deadlock, when it also tries to
699  *   grab the same mutex.
700  */
701 static void dlfb_dpy_deferred_io(struct fb_info *info,
702                                 struct list_head *pagelist)
703 {
704         struct page *cur;
705         struct fb_deferred_io *fbdefio = info->fbdefio;
706         struct dlfb_data *dev = info->par;
707         struct urb *urb;
708         char *cmd;
709         cycles_t start_cycles, end_cycles;
710         int bytes_sent = 0;
711         int bytes_identical = 0;
712         int bytes_rendered = 0;
713
714         if (!fb_defio)
715                 return;
716
717         if (!atomic_read(&dev->usb_active))
718                 return;
719
720         start_cycles = get_cycles();
721
722         urb = dlfb_get_urb(dev);
723         if (!urb)
724                 return;
725
726         cmd = urb->transfer_buffer;
727
728         /* walk the written page list and render each to device */
729         list_for_each_entry(cur, &fbdefio->pagelist, lru) {
730
731                 if (dlfb_render_hline(dev, &urb, (char *) info->fix.smem_start,
732                                   &cmd, cur->index << PAGE_SHIFT,
733                                   PAGE_SIZE, &bytes_identical, &bytes_sent))
734                         goto error;
735                 bytes_rendered += PAGE_SIZE;
736         }
737
738         if (cmd > (char *) urb->transfer_buffer) {
739                 /* Send partial buffer remaining before exiting */
740                 int len = cmd - (char *) urb->transfer_buffer;
741                 dlfb_submit_urb(dev, urb, len);
742                 bytes_sent += len;
743         } else
744                 dlfb_urb_completion(urb);
745
746 error:
747         atomic_add(bytes_sent, &dev->bytes_sent);
748         atomic_add(bytes_identical, &dev->bytes_identical);
749         atomic_add(bytes_rendered, &dev->bytes_rendered);
750         end_cycles = get_cycles();
751         atomic_add(((unsigned int) ((end_cycles - start_cycles)
752                     >> 10)), /* Kcycles */
753                    &dev->cpu_kcycles_used);
754 }
755
756 static int dlfb_get_edid(struct dlfb_data *dev, char *edid, int len)
757 {
758         int i;
759         int ret;
760         char *rbuf;
761
762         rbuf = kmalloc(2, GFP_KERNEL);
763         if (!rbuf)
764                 return 0;
765
766         for (i = 0; i < len; i++) {
767                 ret = usb_control_msg(dev->udev,
768                                     usb_rcvctrlpipe(dev->udev, 0), (0x02),
769                                     (0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2,
770                                     HZ);
771                 if (ret < 1) {
772                         pr_err("Read EDID byte %d failed err %x\n", i, ret);
773                         i--;
774                         break;
775                 }
776                 edid[i] = rbuf[1];
777         }
778
779         kfree(rbuf);
780
781         return i;
782 }
783
784 static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd,
785                                 unsigned long arg)
786 {
787
788         struct dlfb_data *dev = info->par;
789
790         if (!atomic_read(&dev->usb_active))
791                 return 0;
792
793         /* TODO: Update X server to get this from sysfs instead */
794         if (cmd == DLFB_IOCTL_RETURN_EDID) {
795                 void __user *edid = (void __user *)arg;
796                 if (copy_to_user(edid, dev->edid, dev->edid_size))
797                         return -EFAULT;
798                 return 0;
799         }
800
801         /* TODO: Help propose a standard fb.h ioctl to report mmap damage */
802         if (cmd == DLFB_IOCTL_REPORT_DAMAGE) {
803                 struct dloarea area;
804
805                 if (copy_from_user(&area, (void __user *)arg,
806                                   sizeof(struct dloarea)))
807                         return -EFAULT;
808
809                 /*
810                  * If we have a damage-aware client, turn fb_defio "off"
811                  * To avoid perf imact of unnecessary page fault handling.
812                  * Done by resetting the delay for this fb_info to a very
813                  * long period. Pages will become writable and stay that way.
814                  * Reset to normal value when all clients have closed this fb.
815                  */
816                 if (info->fbdefio)
817                         info->fbdefio->delay = DL_DEFIO_WRITE_DISABLE;
818
819                 if (area.x < 0)
820                         area.x = 0;
821
822                 if (area.x > info->var.xres)
823                         area.x = info->var.xres;
824
825                 if (area.y < 0)
826                         area.y = 0;
827
828                 if (area.y > info->var.yres)
829                         area.y = info->var.yres;
830
831                 dlfb_handle_damage(dev, area.x, area.y, area.w, area.h,
832                            info->screen_base);
833         }
834
835         return 0;
836 }
837
838 /* taken from vesafb */
839 static int
840 dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green,
841                unsigned blue, unsigned transp, struct fb_info *info)
842 {
843         int err = 0;
844
845         if (regno >= info->cmap.len)
846                 return 1;
847
848         if (regno < 16) {
849                 if (info->var.red.offset == 10) {
850                         /* 1:5:5:5 */
851                         ((u32 *) (info->pseudo_palette))[regno] =
852                             ((red & 0xf800) >> 1) |
853                             ((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11);
854                 } else {
855                         /* 0:5:6:5 */
856                         ((u32 *) (info->pseudo_palette))[regno] =
857                             ((red & 0xf800)) |
858                             ((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11);
859                 }
860         }
861
862         return err;
863 }
864
865 /*
866  * It's common for several clients to have framebuffer open simultaneously.
867  * e.g. both fbcon and X. Makes things interesting.
868  * Assumes caller is holding info->lock (for open and release at least)
869  */
870 static int dlfb_ops_open(struct fb_info *info, int user)
871 {
872         struct dlfb_data *dev = info->par;
873
874         /*
875          * fbcon aggressively connects to first framebuffer it finds,
876          * preventing other clients (X) from working properly. Usually
877          * not what the user wants. Fail by default with option to enable.
878          */
879         if ((user == 0) && (!console))
880                 return -EBUSY;
881
882         /* If the USB device is gone, we don't accept new opens */
883         if (dev->virtualized)
884                 return -ENODEV;
885
886         dev->fb_count++;
887
888         kref_get(&dev->kref);
889
890         if (fb_defio && (info->fbdefio == NULL)) {
891                 /* enable defio at last moment if not disabled by client */
892
893                 struct fb_deferred_io *fbdefio;
894
895                 fbdefio = kmalloc(sizeof(struct fb_deferred_io), GFP_KERNEL);
896
897                 if (fbdefio) {
898                         fbdefio->delay = DL_DEFIO_WRITE_DELAY;
899                         fbdefio->deferred_io = dlfb_dpy_deferred_io;
900                 }
901
902                 info->fbdefio = fbdefio;
903                 fb_deferred_io_init(info);
904         }
905
906         pr_notice("open /dev/fb%d user=%d fb_info=%p count=%d\n",
907             info->node, user, info, dev->fb_count);
908
909         return 0;
910 }
911
912 /*
913  * Called when all client interfaces to start transactions have been disabled,
914  * and all references to our device instance (dlfb_data) are released.
915  * Every transaction must have a reference, so we know are fully spun down
916  */
917 static void dlfb_free(struct kref *kref)
918 {
919         struct dlfb_data *dev = container_of(kref, struct dlfb_data, kref);
920
921         /* this function will wait for all in-flight urbs to complete */
922         if (dev->urbs.count > 0)
923                 dlfb_free_urb_list(dev);
924
925         if (dev->backing_buffer)
926                 vfree(dev->backing_buffer);
927
928         kfree(dev->edid);
929
930         pr_warn("freeing dlfb_data %p\n", dev);
931
932         kfree(dev);
933 }
934
935 static void dlfb_release_urb_work(struct work_struct *work)
936 {
937         struct urb_node *unode = container_of(work, struct urb_node,
938                                               release_urb_work.work);
939
940         up(&unode->dev->urbs.limit_sem);
941 }
942
943 static void dlfb_free_framebuffer_work(struct work_struct *work)
944 {
945         struct dlfb_data *dev = container_of(work, struct dlfb_data,
946                                              free_framebuffer_work.work);
947         struct fb_info *info = dev->info;
948         int node = info->node;
949
950         unregister_framebuffer(info);
951
952         if (info->cmap.len != 0)
953                 fb_dealloc_cmap(&info->cmap);
954         if (info->monspecs.modedb)
955                 fb_destroy_modedb(info->monspecs.modedb);
956         if (info->screen_base)
957                 vfree(info->screen_base);
958
959         fb_destroy_modelist(&info->modelist);
960
961         dev->info = 0;
962
963         /* Assume info structure is freed after this point */
964         framebuffer_release(info);
965
966         pr_warn("fb_info for /dev/fb%d has been freed\n", node);
967
968         /* ref taken in probe() as part of registering framebfufer */
969         kref_put(&dev->kref, dlfb_free);
970 }
971
972 /*
973  * Assumes caller is holding info->lock mutex (for open and release at least)
974  */
975 static int dlfb_ops_release(struct fb_info *info, int user)
976 {
977         struct dlfb_data *dev = info->par;
978
979         dev->fb_count--;
980
981         /* We can't free fb_info here - fbmem will touch it when we return */
982         if (dev->virtualized && (dev->fb_count == 0))
983                 schedule_delayed_work(&dev->free_framebuffer_work, HZ);
984
985         if ((dev->fb_count == 0) && (info->fbdefio)) {
986                 fb_deferred_io_cleanup(info);
987                 kfree(info->fbdefio);
988                 info->fbdefio = NULL;
989                 info->fbops->fb_mmap = dlfb_ops_mmap;
990         }
991
992         pr_warn("released /dev/fb%d user=%d count=%d\n",
993                   info->node, user, dev->fb_count);
994
995         kref_put(&dev->kref, dlfb_free);
996
997         return 0;
998 }
999
1000 /*
1001  * Check whether a video mode is supported by the DisplayLink chip
1002  * We start from monitor's modes, so don't need to filter that here
1003  */
1004 static int dlfb_is_valid_mode(struct fb_videomode *mode,
1005                 struct fb_info *info)
1006 {
1007         struct dlfb_data *dev = info->par;
1008
1009         if (mode->xres * mode->yres > dev->sku_pixel_limit) {
1010                 pr_warn("%dx%d beyond chip capabilities\n",
1011                        mode->xres, mode->yres);
1012                 return 0;
1013         }
1014
1015         pr_info("%dx%d valid mode\n", mode->xres, mode->yres);
1016
1017         return 1;
1018 }
1019
1020 static void dlfb_var_color_format(struct fb_var_screeninfo *var)
1021 {
1022         const struct fb_bitfield red = { 11, 5, 0 };
1023         const struct fb_bitfield green = { 5, 6, 0 };
1024         const struct fb_bitfield blue = { 0, 5, 0 };
1025
1026         var->bits_per_pixel = 16;
1027         var->red = red;
1028         var->green = green;
1029         var->blue = blue;
1030 }
1031
1032 static int dlfb_ops_check_var(struct fb_var_screeninfo *var,
1033                                 struct fb_info *info)
1034 {
1035         struct fb_videomode mode;
1036
1037         /* TODO: support dynamically changing framebuffer size */
1038         if ((var->xres * var->yres * 2) > info->fix.smem_len)
1039                 return -EINVAL;
1040
1041         /* set device-specific elements of var unrelated to mode */
1042         dlfb_var_color_format(var);
1043
1044         fb_var_to_videomode(&mode, var);
1045
1046         if (!dlfb_is_valid_mode(&mode, info))
1047                 return -EINVAL;
1048
1049         return 0;
1050 }
1051
1052 static int dlfb_ops_set_par(struct fb_info *info)
1053 {
1054         struct dlfb_data *dev = info->par;
1055         int result;
1056         u16 *pix_framebuffer;
1057         int i;
1058
1059         pr_notice("set_par mode %dx%d\n", info->var.xres, info->var.yres);
1060
1061         result = dlfb_set_video_mode(dev, &info->var);
1062
1063         if ((result == 0) && (dev->fb_count == 0)) {
1064
1065                 /* paint greenscreen */
1066
1067                 pix_framebuffer = (u16 *) info->screen_base;
1068                 for (i = 0; i < info->fix.smem_len / 2; i++)
1069                         pix_framebuffer[i] = 0x37e6;
1070
1071                 dlfb_handle_damage(dev, 0, 0, info->var.xres, info->var.yres,
1072                                    info->screen_base);
1073         }
1074
1075         return result;
1076 }
1077
1078 /* To fonzi the jukebox (e.g. make blanking changes take effect) */
1079 static char *dlfb_dummy_render(char *buf)
1080 {
1081         *buf++ = 0xAF;
1082         *buf++ = 0x6A; /* copy */
1083         *buf++ = 0x00; /* from address*/
1084         *buf++ = 0x00;
1085         *buf++ = 0x00;
1086         *buf++ = 0x01; /* one pixel */
1087         *buf++ = 0x00; /* to address */
1088         *buf++ = 0x00;
1089         *buf++ = 0x00;
1090         return buf;
1091 }
1092
1093 /*
1094  * In order to come back from full DPMS off, we need to set the mode again
1095  */
1096 static int dlfb_ops_blank(int blank_mode, struct fb_info *info)
1097 {
1098         struct dlfb_data *dev = info->par;
1099         char *bufptr;
1100         struct urb *urb;
1101
1102         pr_info("/dev/fb%d FB_BLANK mode %d --> %d\n",
1103                 info->node, dev->blank_mode, blank_mode);
1104
1105         if ((dev->blank_mode == FB_BLANK_POWERDOWN) &&
1106             (blank_mode != FB_BLANK_POWERDOWN)) {
1107
1108                 /* returning from powerdown requires a fresh modeset */
1109                 dlfb_set_video_mode(dev, &info->var);
1110         }
1111
1112         urb = dlfb_get_urb(dev);
1113         if (!urb)
1114                 return 0;
1115
1116         bufptr = (char *) urb->transfer_buffer;
1117         bufptr = dlfb_vidreg_lock(bufptr);
1118         bufptr = dlfb_blanking(bufptr, blank_mode);
1119         bufptr = dlfb_vidreg_unlock(bufptr);
1120
1121         /* seems like a render op is needed to have blank change take effect */
1122         bufptr = dlfb_dummy_render(bufptr);
1123
1124         dlfb_submit_urb(dev, urb, bufptr -
1125                         (char *) urb->transfer_buffer);
1126
1127         dev->blank_mode = blank_mode;
1128
1129         return 0;
1130 }
1131
1132 static struct fb_ops dlfb_ops = {
1133         .owner = THIS_MODULE,
1134         .fb_read = fb_sys_read,
1135         .fb_write = dlfb_ops_write,
1136         .fb_setcolreg = dlfb_ops_setcolreg,
1137         .fb_fillrect = dlfb_ops_fillrect,
1138         .fb_copyarea = dlfb_ops_copyarea,
1139         .fb_imageblit = dlfb_ops_imageblit,
1140         .fb_mmap = dlfb_ops_mmap,
1141         .fb_ioctl = dlfb_ops_ioctl,
1142         .fb_open = dlfb_ops_open,
1143         .fb_release = dlfb_ops_release,
1144         .fb_blank = dlfb_ops_blank,
1145         .fb_check_var = dlfb_ops_check_var,
1146         .fb_set_par = dlfb_ops_set_par,
1147 };
1148
1149
1150 /*
1151  * Assumes &info->lock held by caller
1152  * Assumes no active clients have framebuffer open
1153  */
1154 static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info)
1155 {
1156         int retval = -ENOMEM;
1157         int old_len = info->fix.smem_len;
1158         int new_len;
1159         unsigned char *old_fb = info->screen_base;
1160         unsigned char *new_fb;
1161         unsigned char *new_back = 0;
1162
1163         pr_warn("Reallocating framebuffer. Addresses will change!\n");
1164
1165         new_len = info->fix.line_length * info->var.yres;
1166
1167         if (PAGE_ALIGN(new_len) > old_len) {
1168                 /*
1169                  * Alloc system memory for virtual framebuffer
1170                  */
1171                 new_fb = vmalloc(new_len);
1172                 if (!new_fb) {
1173                         pr_err("Virtual framebuffer alloc failed\n");
1174                         goto error;
1175                 }
1176
1177                 if (info->screen_base) {
1178                         memcpy(new_fb, old_fb, old_len);
1179                         vfree(info->screen_base);
1180                 }
1181
1182                 info->screen_base = new_fb;
1183                 info->fix.smem_len = PAGE_ALIGN(new_len);
1184                 info->fix.smem_start = (unsigned long) new_fb;
1185                 info->flags = udlfb_info_flags;
1186
1187                 /*
1188                  * Second framebuffer copy to mirror the framebuffer state
1189                  * on the physical USB device. We can function without this.
1190                  * But with imperfect damage info we may send pixels over USB
1191                  * that were, in fact, unchanged - wasting limited USB bandwidth
1192                  */
1193                 if (shadow)
1194                         new_back = vzalloc(new_len);
1195                 if (!new_back)
1196                         pr_info("No shadow/backing buffer allocated\n");
1197                 else {
1198                         if (dev->backing_buffer)
1199                                 vfree(dev->backing_buffer);
1200                         dev->backing_buffer = new_back;
1201                 }
1202         }
1203
1204         retval = 0;
1205
1206 error:
1207         return retval;
1208 }
1209
1210 /*
1211  * 1) Get EDID from hw, or use sw default
1212  * 2) Parse into various fb_info structs
1213  * 3) Allocate virtual framebuffer memory to back highest res mode
1214  *
1215  * Parses EDID into three places used by various parts of fbdev:
1216  * fb_var_screeninfo contains the timing of the monitor's preferred mode
1217  * fb_info.monspecs is full parsed EDID info, including monspecs.modedb
1218  * fb_info.modelist is a linked list of all monitor & VESA modes which work
1219  *
1220  * If EDID is not readable/valid, then modelist is all VESA modes,
1221  * monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode
1222  * Returns 0 if successful
1223  */
1224 static int dlfb_setup_modes(struct dlfb_data *dev,
1225                            struct fb_info *info,
1226                            char *default_edid, size_t default_edid_size)
1227 {
1228         int i;
1229         const struct fb_videomode *default_vmode = NULL;
1230         int result = 0;
1231         char *edid;
1232         int tries = 3;
1233
1234         if (info->dev) /* only use mutex if info has been registered */
1235                 mutex_lock(&info->lock);
1236
1237         edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
1238         if (!edid) {
1239                 result = -ENOMEM;
1240                 goto error;
1241         }
1242
1243         fb_destroy_modelist(&info->modelist);
1244         memset(&info->monspecs, 0, sizeof(info->monspecs));
1245
1246         /*
1247          * Try to (re)read EDID from hardware first
1248          * EDID data may return, but not parse as valid
1249          * Try again a few times, in case of e.g. analog cable noise
1250          */
1251         while (tries--) {
1252
1253                 i = dlfb_get_edid(dev, edid, EDID_LENGTH);
1254
1255                 if (i >= EDID_LENGTH)
1256                         fb_edid_to_monspecs(edid, &info->monspecs);
1257
1258                 if (info->monspecs.modedb_len > 0) {
1259                         dev->edid = edid;
1260                         dev->edid_size = i;
1261                         break;
1262                 }
1263         }
1264
1265         /* If that fails, use a previously returned EDID if available */
1266         if (info->monspecs.modedb_len == 0) {
1267
1268                 pr_err("Unable to get valid EDID from device/display\n");
1269
1270                 if (dev->edid) {
1271                         fb_edid_to_monspecs(dev->edid, &info->monspecs);
1272                         if (info->monspecs.modedb_len > 0)
1273                                 pr_err("Using previously queried EDID\n");
1274                 }
1275         }
1276
1277         /* If that fails, use the default EDID we were handed */
1278         if (info->monspecs.modedb_len == 0) {
1279                 if (default_edid_size >= EDID_LENGTH) {
1280                         fb_edid_to_monspecs(default_edid, &info->monspecs);
1281                         if (info->monspecs.modedb_len > 0) {
1282                                 memcpy(edid, default_edid, default_edid_size);
1283                                 dev->edid = edid;
1284                                 dev->edid_size = default_edid_size;
1285                                 pr_err("Using default/backup EDID\n");
1286                         }
1287                 }
1288         }
1289
1290         /* If we've got modes, let's pick a best default mode */
1291         if (info->monspecs.modedb_len > 0) {
1292
1293                 for (i = 0; i < info->monspecs.modedb_len; i++) {
1294                         if (dlfb_is_valid_mode(&info->monspecs.modedb[i], info))
1295                                 fb_add_videomode(&info->monspecs.modedb[i],
1296                                         &info->modelist);
1297                         else {
1298                                 if (i == 0)
1299                                         /* if we've removed top/best mode */
1300                                         info->monspecs.misc
1301                                                 &= ~FB_MISC_1ST_DETAIL;
1302                         }
1303                 }
1304
1305                 default_vmode = fb_find_best_display(&info->monspecs,
1306                                                      &info->modelist);
1307         }
1308
1309         /* If everything else has failed, fall back to safe default mode */
1310         if (default_vmode == NULL) {
1311
1312                 struct fb_videomode fb_vmode = {0};
1313
1314                 /*
1315                  * Add the standard VESA modes to our modelist
1316                  * Since we don't have EDID, there may be modes that
1317                  * overspec monitor and/or are incorrect aspect ratio, etc.
1318                  * But at least the user has a chance to choose
1319                  */
1320                 for (i = 0; i < VESA_MODEDB_SIZE; i++) {
1321                         if (dlfb_is_valid_mode((struct fb_videomode *)
1322                                                 &vesa_modes[i], info))
1323                                 fb_add_videomode(&vesa_modes[i],
1324                                                  &info->modelist);
1325                 }
1326
1327                 /*
1328                  * default to resolution safe for projectors
1329                  * (since they are most common case without EDID)
1330                  */
1331                 fb_vmode.xres = 800;
1332                 fb_vmode.yres = 600;
1333                 fb_vmode.refresh = 60;
1334                 default_vmode = fb_find_nearest_mode(&fb_vmode,
1335                                                      &info->modelist);
1336         }
1337
1338         /* If we have good mode and no active clients*/
1339         if ((default_vmode != NULL) && (dev->fb_count == 0)) {
1340
1341                 fb_videomode_to_var(&info->var, default_vmode);
1342                 dlfb_var_color_format(&info->var);
1343
1344                 /*
1345                  * with mode size info, we can now alloc our framebuffer.
1346                  */
1347                 memcpy(&info->fix, &dlfb_fix, sizeof(dlfb_fix));
1348                 info->fix.line_length = info->var.xres *
1349                         (info->var.bits_per_pixel / 8);
1350
1351                 result = dlfb_realloc_framebuffer(dev, info);
1352
1353         } else
1354                 result = -EINVAL;
1355
1356 error:
1357         if (edid && (dev->edid != edid))
1358                 kfree(edid);
1359
1360         if (info->dev)
1361                 mutex_unlock(&info->lock);
1362
1363         return result;
1364 }
1365
1366 static ssize_t metrics_bytes_rendered_show(struct device *fbdev,
1367                                    struct device_attribute *a, char *buf) {
1368         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1369         struct dlfb_data *dev = fb_info->par;
1370         return snprintf(buf, PAGE_SIZE, "%u\n",
1371                         atomic_read(&dev->bytes_rendered));
1372 }
1373
1374 static ssize_t metrics_bytes_identical_show(struct device *fbdev,
1375                                    struct device_attribute *a, char *buf) {
1376         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1377         struct dlfb_data *dev = fb_info->par;
1378         return snprintf(buf, PAGE_SIZE, "%u\n",
1379                         atomic_read(&dev->bytes_identical));
1380 }
1381
1382 static ssize_t metrics_bytes_sent_show(struct device *fbdev,
1383                                    struct device_attribute *a, char *buf) {
1384         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1385         struct dlfb_data *dev = fb_info->par;
1386         return snprintf(buf, PAGE_SIZE, "%u\n",
1387                         atomic_read(&dev->bytes_sent));
1388 }
1389
1390 static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev,
1391                                    struct device_attribute *a, char *buf) {
1392         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1393         struct dlfb_data *dev = fb_info->par;
1394         return snprintf(buf, PAGE_SIZE, "%u\n",
1395                         atomic_read(&dev->cpu_kcycles_used));
1396 }
1397
1398 static ssize_t edid_show(
1399                         struct file *filp,
1400                         struct kobject *kobj, struct bin_attribute *a,
1401                          char *buf, loff_t off, size_t count) {
1402         struct device *fbdev = container_of(kobj, struct device, kobj);
1403         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1404         struct dlfb_data *dev = fb_info->par;
1405
1406         if (dev->edid == NULL)
1407                 return 0;
1408
1409         if ((off >= dev->edid_size) || (count > dev->edid_size))
1410                 return 0;
1411
1412         if (off + count > dev->edid_size)
1413                 count = dev->edid_size - off;
1414
1415         pr_info("sysfs edid copy %p to %p, %d bytes\n",
1416                 dev->edid, buf, (int) count);
1417
1418         memcpy(buf, dev->edid, count);
1419
1420         return count;
1421 }
1422
1423 static ssize_t edid_store(
1424                         struct file *filp,
1425                         struct kobject *kobj, struct bin_attribute *a,
1426                         char *src, loff_t src_off, size_t src_size) {
1427         struct device *fbdev = container_of(kobj, struct device, kobj);
1428         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1429         struct dlfb_data *dev = fb_info->par;
1430
1431         /* We only support write of entire EDID at once, no offset*/
1432         if ((src_size != EDID_LENGTH) || (src_off != 0))
1433                 return 0;
1434
1435         dlfb_setup_modes(dev, fb_info, src, src_size);
1436
1437         if (dev->edid && (memcmp(src, dev->edid, src_size) == 0)) {
1438                 pr_info("sysfs written EDID is new default\n");
1439                 dlfb_ops_set_par(fb_info);
1440                 return src_size;
1441         } else
1442                 return 0;
1443 }
1444
1445 static ssize_t metrics_reset_store(struct device *fbdev,
1446                            struct device_attribute *attr,
1447                            const char *buf, size_t count)
1448 {
1449         struct fb_info *fb_info = dev_get_drvdata(fbdev);
1450         struct dlfb_data *dev = fb_info->par;
1451
1452         atomic_set(&dev->bytes_rendered, 0);
1453         atomic_set(&dev->bytes_identical, 0);
1454         atomic_set(&dev->bytes_sent, 0);
1455         atomic_set(&dev->cpu_kcycles_used, 0);
1456
1457         return count;
1458 }
1459
1460 static struct bin_attribute edid_attr = {
1461         .attr.name = "edid",
1462         .attr.mode = 0666,
1463         .size = EDID_LENGTH,
1464         .read = edid_show,
1465         .write = edid_store
1466 };
1467
1468 static struct device_attribute fb_device_attrs[] = {
1469         __ATTR_RO(metrics_bytes_rendered),
1470         __ATTR_RO(metrics_bytes_identical),
1471         __ATTR_RO(metrics_bytes_sent),
1472         __ATTR_RO(metrics_cpu_kcycles_used),
1473         __ATTR(metrics_reset, S_IWUSR, NULL, metrics_reset_store),
1474 };
1475
1476 /*
1477  * This is necessary before we can communicate with the display controller.
1478  */
1479 static int dlfb_select_std_channel(struct dlfb_data *dev)
1480 {
1481         int ret;
1482         u8 set_def_chn[] = {       0x57, 0xCD, 0xDC, 0xA7,
1483                                 0x1C, 0x88, 0x5E, 0x15,
1484                                 0x60, 0xFE, 0xC6, 0x97,
1485                                 0x16, 0x3D, 0x47, 0xF2  };
1486
1487         ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
1488                         NR_USB_REQUEST_CHANNEL,
1489                         (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
1490                         set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT);
1491         return ret;
1492 }
1493
1494 static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
1495                                         struct usb_interface *interface)
1496 {
1497         char *desc;
1498         char *buf;
1499         char *desc_end;
1500
1501         int total_len = 0;
1502
1503         buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);
1504         if (!buf)
1505                 return false;
1506         desc = buf;
1507
1508         total_len = usb_get_descriptor(interface_to_usbdev(interface),
1509                                         0x5f, /* vendor specific */
1510                                         0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
1511
1512         /* if not found, look in configuration descriptor */
1513         if (total_len < 0) {
1514                 if (0 == usb_get_extra_descriptor(interface->cur_altsetting,
1515                         0x5f, &desc))
1516                         total_len = (int) desc[0];
1517         }
1518
1519         if (total_len > 5) {
1520                 pr_info("vendor descriptor length:%x data:%02x %02x %02x %02x" \
1521                         "%02x %02x %02x %02x %02x %02x %02x\n",
1522                         total_len, desc[0],
1523                         desc[1], desc[2], desc[3], desc[4], desc[5], desc[6],
1524                         desc[7], desc[8], desc[9], desc[10]);
1525
1526                 if ((desc[0] != total_len) || /* descriptor length */
1527                     (desc[1] != 0x5f) ||   /* vendor descriptor type */
1528                     (desc[2] != 0x01) ||   /* version (2 bytes) */
1529                     (desc[3] != 0x00) ||
1530                     (desc[4] != total_len - 2)) /* length after type */
1531                         goto unrecognized;
1532
1533                 desc_end = desc + total_len;
1534                 desc += 5; /* the fixed header we've already parsed */
1535
1536                 while (desc < desc_end) {
1537                         u8 length;
1538                         u16 key;
1539
1540                         key = *((u16 *) desc);
1541                         desc += sizeof(u16);
1542                         length = *desc;
1543                         desc++;
1544
1545                         switch (key) {
1546                         case 0x0200: { /* max_area */
1547                                 u32 max_area;
1548                                 max_area = le32_to_cpu(*((u32 *)desc));
1549                                 pr_warn("DL chip limited to %d pixel modes\n",
1550                                         max_area);
1551                                 dev->sku_pixel_limit = max_area;
1552                                 break;
1553                         }
1554                         default:
1555                                 break;
1556                         }
1557                         desc += length;
1558                 }
1559         } else {
1560                 pr_info("vendor descriptor not available (%d)\n", total_len);
1561         }
1562
1563         goto success;
1564
1565 unrecognized:
1566         /* allow udlfb to load for now even if firmware unrecognized */
1567         pr_err("Unrecognized vendor firmware descriptor\n");
1568
1569 success:
1570         kfree(buf);
1571         return true;
1572 }
1573 static int dlfb_usb_probe(struct usb_interface *interface,
1574                         const struct usb_device_id *id)
1575 {
1576         struct usb_device *usbdev;
1577         struct dlfb_data *dev = 0;
1578         struct fb_info *info = 0;
1579         int retval = -ENOMEM;
1580         int i;
1581
1582         /* usb initialization */
1583
1584         usbdev = interface_to_usbdev(interface);
1585
1586         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1587         if (dev == NULL) {
1588                 err("dlfb_usb_probe: failed alloc of dev struct\n");
1589                 goto error;
1590         }
1591
1592         /* we need to wait for both usb and fbdev to spin down on disconnect */
1593         kref_init(&dev->kref); /* matching kref_put in usb .disconnect fn */
1594         kref_get(&dev->kref); /* matching kref_put in free_framebuffer_work */
1595
1596         dev->udev = usbdev;
1597         dev->gdev = &usbdev->dev; /* our generic struct device * */
1598         usb_set_intfdata(interface, dev);
1599
1600         pr_info("%s %s - serial #%s\n",
1601                 usbdev->manufacturer, usbdev->product, usbdev->serial);
1602         pr_info("vid_%04x&pid_%04x&rev_%04x driver's dlfb_data struct at %p\n",
1603                 usbdev->descriptor.idVendor, usbdev->descriptor.idProduct,
1604                 usbdev->descriptor.bcdDevice, dev);
1605         pr_info("console enable=%d\n", console);
1606         pr_info("fb_defio enable=%d\n", fb_defio);
1607         pr_info("shadow enable=%d\n", shadow);
1608
1609         dev->sku_pixel_limit = 2048 * 1152; /* default to maximum */
1610
1611         if (!dlfb_parse_vendor_descriptor(dev, interface)) {
1612                 pr_err("firmware not recognized. Assume incompatible device\n");
1613                 goto error;
1614         }
1615
1616         if (!dlfb_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
1617                 retval = -ENOMEM;
1618                 pr_err("dlfb_alloc_urb_list failed\n");
1619                 goto error;
1620         }
1621
1622         /* We don't register a new USB class. Our client interface is fbdev */
1623
1624         /* allocates framebuffer driver structure, not framebuffer memory */
1625         info = framebuffer_alloc(0, &interface->dev);
1626         if (!info) {
1627                 retval = -ENOMEM;
1628                 pr_err("framebuffer_alloc failed\n");
1629                 goto error;
1630         }
1631
1632         dev->info = info;
1633         info->par = dev;
1634         info->pseudo_palette = dev->pseudo_palette;
1635         info->fbops = &dlfb_ops;
1636
1637         retval = fb_alloc_cmap(&info->cmap, 256, 0);
1638         if (retval < 0) {
1639                 pr_err("fb_alloc_cmap failed %x\n", retval);
1640                 goto error;
1641         }
1642
1643         INIT_DELAYED_WORK(&dev->free_framebuffer_work,
1644                           dlfb_free_framebuffer_work);
1645
1646         INIT_LIST_HEAD(&info->modelist);
1647
1648         retval = dlfb_setup_modes(dev, info, NULL, 0);
1649         if (retval != 0) {
1650                 pr_err("unable to find common mode for display and adapter\n");
1651                 goto error;
1652         }
1653
1654         /* ready to begin using device */
1655
1656         atomic_set(&dev->usb_active, 1);
1657         dlfb_select_std_channel(dev);
1658
1659         dlfb_ops_check_var(&info->var, info);
1660         dlfb_ops_set_par(info);
1661
1662         retval = register_framebuffer(info);
1663         if (retval < 0) {
1664                 pr_err("register_framebuffer failed %d\n", retval);
1665                 goto error;
1666         }
1667
1668         for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) {
1669                 retval = device_create_file(info->dev, &fb_device_attrs[i]);
1670                 if (retval) {
1671                         pr_err("device_create_file failed %d\n", retval);
1672                         goto err_del_attrs;
1673                 }
1674         }
1675
1676         retval = device_create_bin_file(info->dev, &edid_attr);
1677         if (retval) {
1678                 pr_err("device_create_bin_file failed %d\n", retval);
1679                 goto err_del_attrs;
1680         }
1681
1682         pr_info("DisplayLink USB device /dev/fb%d attached. %dx%d resolution."
1683                         " Using %dK framebuffer memory\n", info->node,
1684                         info->var.xres, info->var.yres,
1685                         ((dev->backing_buffer) ?
1686                         info->fix.smem_len * 2 : info->fix.smem_len) >> 10);
1687         return 0;
1688
1689 err_del_attrs:
1690         for (i -= 1; i >= 0; i--)
1691                 device_remove_file(info->dev, &fb_device_attrs[i]);
1692
1693 error:
1694         if (dev) {
1695
1696                 if (info) {
1697                         if (info->cmap.len != 0)
1698                                 fb_dealloc_cmap(&info->cmap);
1699                         if (info->monspecs.modedb)
1700                                 fb_destroy_modedb(info->monspecs.modedb);
1701                         if (info->screen_base)
1702                                 vfree(info->screen_base);
1703
1704                         fb_destroy_modelist(&info->modelist);
1705
1706                         framebuffer_release(info);
1707                 }
1708
1709                 if (dev->backing_buffer)
1710                         vfree(dev->backing_buffer);
1711
1712                 kref_put(&dev->kref, dlfb_free); /* ref for framebuffer */
1713                 kref_put(&dev->kref, dlfb_free); /* last ref from kref_init */
1714
1715                 /* dev has been deallocated. Do not dereference */
1716         }
1717
1718         return retval;
1719 }
1720
1721 static void dlfb_usb_disconnect(struct usb_interface *interface)
1722 {
1723         struct dlfb_data *dev;
1724         struct fb_info *info;
1725         int i;
1726
1727         dev = usb_get_intfdata(interface);
1728         info = dev->info;
1729
1730         pr_info("USB disconnect starting\n");
1731
1732         /* we virtualize until all fb clients release. Then we free */
1733         dev->virtualized = true;
1734
1735         /* When non-active we'll update virtual framebuffer, but no new urbs */
1736         atomic_set(&dev->usb_active, 0);
1737
1738         /* remove udlfb's sysfs interfaces */
1739         for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
1740                 device_remove_file(info->dev, &fb_device_attrs[i]);
1741         device_remove_bin_file(info->dev, &edid_attr);
1742
1743         usb_set_intfdata(interface, NULL);
1744
1745         /* if clients still have us open, will be freed on last close */
1746         if (dev->fb_count == 0)
1747                 schedule_delayed_work(&dev->free_framebuffer_work, 0);
1748
1749         /* release reference taken by kref_init in probe() */
1750         kref_put(&dev->kref, dlfb_free);
1751
1752         /* consider dlfb_data freed */
1753
1754         return;
1755 }
1756
1757 static struct usb_driver dlfb_driver = {
1758         .name = "udlfb",
1759         .probe = dlfb_usb_probe,
1760         .disconnect = dlfb_usb_disconnect,
1761         .id_table = id_table,
1762 };
1763
1764 module_usb_driver(dlfb_driver);
1765
1766 static void dlfb_urb_completion(struct urb *urb)
1767 {
1768         struct urb_node *unode = urb->context;
1769         struct dlfb_data *dev = unode->dev;
1770         unsigned long flags;
1771
1772         /* sync/async unlink faults aren't errors */
1773         if (urb->status) {
1774                 if (!(urb->status == -ENOENT ||
1775                     urb->status == -ECONNRESET ||
1776                     urb->status == -ESHUTDOWN)) {
1777                         pr_err("%s - nonzero write bulk status received: %d\n",
1778                                 __func__, urb->status);
1779                         atomic_set(&dev->lost_pixels, 1);
1780                 }
1781         }
1782
1783         urb->transfer_buffer_length = dev->urbs.size; /* reset to actual */
1784
1785         spin_lock_irqsave(&dev->urbs.lock, flags);
1786         list_add_tail(&unode->entry, &dev->urbs.list);
1787         dev->urbs.available++;
1788         spin_unlock_irqrestore(&dev->urbs.lock, flags);
1789
1790         /*
1791          * When using fb_defio, we deadlock if up() is called
1792          * while another is waiting. So queue to another process.
1793          */
1794         if (fb_defio)
1795                 schedule_delayed_work(&unode->release_urb_work, 0);
1796         else
1797                 up(&dev->urbs.limit_sem);
1798 }
1799
1800 static void dlfb_free_urb_list(struct dlfb_data *dev)
1801 {
1802         int count = dev->urbs.count;
1803         struct list_head *node;
1804         struct urb_node *unode;
1805         struct urb *urb;
1806         int ret;
1807         unsigned long flags;
1808
1809         pr_notice("Waiting for completes and freeing all render urbs\n");
1810
1811         /* keep waiting and freeing, until we've got 'em all */
1812         while (count--) {
1813
1814                 /* Getting interrupted means a leak, but ok at shutdown*/
1815                 ret = down_interruptible(&dev->urbs.limit_sem);
1816                 if (ret)
1817                         break;
1818
1819                 spin_lock_irqsave(&dev->urbs.lock, flags);
1820
1821                 node = dev->urbs.list.next; /* have reserved one with sem */
1822                 list_del_init(node);
1823
1824                 spin_unlock_irqrestore(&dev->urbs.lock, flags);
1825
1826                 unode = list_entry(node, struct urb_node, entry);
1827                 urb = unode->urb;
1828
1829                 /* Free each separately allocated piece */
1830                 usb_free_coherent(urb->dev, dev->urbs.size,
1831                                   urb->transfer_buffer, urb->transfer_dma);
1832                 usb_free_urb(urb);
1833                 kfree(node);
1834         }
1835
1836 }
1837
1838 static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size)
1839 {
1840         int i = 0;
1841         struct urb *urb;
1842         struct urb_node *unode;
1843         char *buf;
1844
1845         spin_lock_init(&dev->urbs.lock);
1846
1847         dev->urbs.size = size;
1848         INIT_LIST_HEAD(&dev->urbs.list);
1849
1850         while (i < count) {
1851                 unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL);
1852                 if (!unode)
1853                         break;
1854                 unode->dev = dev;
1855
1856                 INIT_DELAYED_WORK(&unode->release_urb_work,
1857                           dlfb_release_urb_work);
1858
1859                 urb = usb_alloc_urb(0, GFP_KERNEL);
1860                 if (!urb) {
1861                         kfree(unode);
1862                         break;
1863                 }
1864                 unode->urb = urb;
1865
1866                 buf = usb_alloc_coherent(dev->udev, MAX_TRANSFER, GFP_KERNEL,
1867                                          &urb->transfer_dma);
1868                 if (!buf) {
1869                         kfree(unode);
1870                         usb_free_urb(urb);
1871                         break;
1872                 }
1873
1874                 /* urb->transfer_buffer_length set to actual before submit */
1875                 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 1),
1876                         buf, size, dlfb_urb_completion, unode);
1877                 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1878
1879                 list_add_tail(&unode->entry, &dev->urbs.list);
1880
1881                 i++;
1882         }
1883
1884         sema_init(&dev->urbs.limit_sem, i);
1885         dev->urbs.count = i;
1886         dev->urbs.available = i;
1887
1888         pr_notice("allocated %d %d byte urbs\n", i, (int) size);
1889
1890         return i;
1891 }
1892
1893 static struct urb *dlfb_get_urb(struct dlfb_data *dev)
1894 {
1895         int ret = 0;
1896         struct list_head *entry;
1897         struct urb_node *unode;
1898         struct urb *urb = NULL;
1899         unsigned long flags;
1900
1901         /* Wait for an in-flight buffer to complete and get re-queued */
1902         ret = down_timeout(&dev->urbs.limit_sem, GET_URB_TIMEOUT);
1903         if (ret) {
1904                 atomic_set(&dev->lost_pixels, 1);
1905                 pr_warn("wait for urb interrupted: %x available: %d\n",
1906                        ret, dev->urbs.available);
1907                 goto error;
1908         }
1909
1910         spin_lock_irqsave(&dev->urbs.lock, flags);
1911
1912         BUG_ON(list_empty(&dev->urbs.list)); /* reserved one with limit_sem */
1913         entry = dev->urbs.list.next;
1914         list_del_init(entry);
1915         dev->urbs.available--;
1916
1917         spin_unlock_irqrestore(&dev->urbs.lock, flags);
1918
1919         unode = list_entry(entry, struct urb_node, entry);
1920         urb = unode->urb;
1921
1922 error:
1923         return urb;
1924 }
1925
1926 static int dlfb_submit_urb(struct dlfb_data *dev, struct urb *urb, size_t len)
1927 {
1928         int ret;
1929
1930         BUG_ON(len > dev->urbs.size);
1931
1932         urb->transfer_buffer_length = len; /* set to actual payload len */
1933         ret = usb_submit_urb(urb, GFP_KERNEL);
1934         if (ret) {
1935                 dlfb_urb_completion(urb); /* because no one else will */
1936                 atomic_set(&dev->lost_pixels, 1);
1937                 pr_err("usb_submit_urb error %x\n", ret);
1938         }
1939         return ret;
1940 }
1941
1942 module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
1943 MODULE_PARM_DESC(console, "Allow fbcon to open framebuffer");
1944
1945 module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
1946 MODULE_PARM_DESC(fb_defio, "Page fault detection of mmap writes");
1947
1948 module_param(shadow, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
1949 MODULE_PARM_DESC(shadow, "Shadow vid mem. Disable to save mem but lose perf");
1950
1951 MODULE_AUTHOR("Roberto De Ioris <roberto@unbit.it>, "
1952               "Jaya Kumar <jayakumar.lkml@gmail.com>, "
1953               "Bernie Thompson <bernie@plugable.com>");
1954 MODULE_DESCRIPTION("DisplayLink kernel framebuffer driver");
1955 MODULE_LICENSE("GPL");
1956