fbdev: move udlfb out of staging.
[pandora-kernel.git] / drivers / staging / udlfb / udlfb.c
diff --git a/drivers/staging/udlfb/udlfb.c b/drivers/staging/udlfb/udlfb.c
deleted file mode 100644 (file)
index fed2510..0000000
+++ /dev/null
@@ -1,1916 +0,0 @@
-/*
- * udlfb.c -- Framebuffer driver for DisplayLink USB controller
- *
- * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
- * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
- * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License v2. See the file COPYING in the main directory of this archive for
- * more details.
- *
- * Layout is based on skeletonfb by James Simmons and Geert Uytterhoeven,
- * usb-skeleton by GregKH.
- *
- * Device-specific portions based on information from Displaylink, with work
- * from Florian Echtler, Henrik Bjerregaard Pedersen, and others.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/usb.h>
-#include <linux/uaccess.h>
-#include <linux/mm.h>
-#include <linux/fb.h>
-#include <linux/vmalloc.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
-
-#include "udlfb.h"
-
-static struct fb_fix_screeninfo dlfb_fix = {
-       .id =           "udlfb",
-       .type =         FB_TYPE_PACKED_PIXELS,
-       .visual =       FB_VISUAL_TRUECOLOR,
-       .xpanstep =     0,
-       .ypanstep =     0,
-       .ywrapstep =    0,
-       .accel =        FB_ACCEL_NONE,
-};
-
-static const u32 udlfb_info_flags = FBINFO_DEFAULT | FBINFO_READS_FAST |
-#ifdef FBINFO_VIRTFB
-               FBINFO_VIRTFB |
-#endif
-               FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT |
-               FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR;
-
-/*
- * There are many DisplayLink-based products, all with unique PIDs. We are able
- * to support all volume ones (circa 2009) with a single driver, so we match
- * globally on VID. TODO: Probe() needs to detect when we might be running
- * "future" chips, and bail on those, so a compatible driver can match.
- */
-static struct usb_device_id id_table[] = {
-       {.idVendor = 0x17e9, .match_flags = USB_DEVICE_ID_MATCH_VENDOR,},
-       {},
-};
-MODULE_DEVICE_TABLE(usb, id_table);
-
-/* module options */
-static int console;   /* Optionally allow fbcon to consume first framebuffer */
-static int fb_defio;  /* Optionally enable experimental fb_defio mmap support */
-
-/* dlfb keeps a list of urbs for efficient bulk transfers */
-static void dlfb_urb_completion(struct urb *urb);
-static struct urb *dlfb_get_urb(struct dlfb_data *dev);
-static int dlfb_submit_urb(struct dlfb_data *dev, struct urb * urb, size_t len);
-static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size);
-static void dlfb_free_urb_list(struct dlfb_data *dev);
-
-/*
- * All DisplayLink bulk operations start with 0xAF, followed by specific code
- * All operations are written to buffers which then later get sent to device
- */
-static char *dlfb_set_register(char *buf, u8 reg, u8 val)
-{
-       *buf++ = 0xAF;
-       *buf++ = 0x20;
-       *buf++ = reg;
-       *buf++ = val;
-       return buf;
-}
-
-static char *dlfb_vidreg_lock(char *buf)
-{
-       return dlfb_set_register(buf, 0xFF, 0x00);
-}
-
-static char *dlfb_vidreg_unlock(char *buf)
-{
-       return dlfb_set_register(buf, 0xFF, 0xFF);
-}
-
-/*
- * On/Off for driving the DisplayLink framebuffer to the display
- *  0x00 H and V sync on
- *  0x01 H and V sync off (screen blank but powered)
- *  0x07 DPMS powerdown (requires modeset to come back)
- */
-static char *dlfb_enable_hvsync(char *buf, bool enable)
-{
-       if (enable)
-               return dlfb_set_register(buf, 0x1F, 0x00);
-       else
-               return dlfb_set_register(buf, 0x1F, 0x07);
-}
-
-static char *dlfb_set_color_depth(char *buf, u8 selection)
-{
-       return dlfb_set_register(buf, 0x00, selection);
-}
-
-static char *dlfb_set_base16bpp(char *wrptr, u32 base)
-{
-       /* the base pointer is 16 bits wide, 0x20 is hi byte. */
-       wrptr = dlfb_set_register(wrptr, 0x20, base >> 16);
-       wrptr = dlfb_set_register(wrptr, 0x21, base >> 8);
-       return dlfb_set_register(wrptr, 0x22, base);
-}
-
-/*
- * DisplayLink HW has separate 16bpp and 8bpp framebuffers.
- * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer
- */
-static char *dlfb_set_base8bpp(char *wrptr, u32 base)
-{
-       wrptr = dlfb_set_register(wrptr, 0x26, base >> 16);
-       wrptr = dlfb_set_register(wrptr, 0x27, base >> 8);
-       return dlfb_set_register(wrptr, 0x28, base);
-}
-
-static char *dlfb_set_register_16(char *wrptr, u8 reg, u16 value)
-{
-       wrptr = dlfb_set_register(wrptr, reg, value >> 8);
-       return dlfb_set_register(wrptr, reg+1, value);
-}
-
-/*
- * This is kind of weird because the controller takes some
- * register values in a different byte order than other registers.
- */
-static char *dlfb_set_register_16be(char *wrptr, u8 reg, u16 value)
-{
-       wrptr = dlfb_set_register(wrptr, reg, value);
-       return dlfb_set_register(wrptr, reg+1, value >> 8);
-}
-
-/*
- * LFSR is linear feedback shift register. The reason we have this is
- * because the display controller needs to minimize the clock depth of
- * various counters used in the display path. So this code reverses the
- * provided value into the lfsr16 value by counting backwards to get
- * the value that needs to be set in the hardware comparator to get the
- * same actual count. This makes sense once you read above a couple of
- * times and think about it from a hardware perspective.
- */
-static u16 dlfb_lfsr16(u16 actual_count)
-{
-       u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */
-
-       while (actual_count--) {
-               lv =     ((lv << 1) |
-                       (((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1))
-                       & 0xFFFF;
-       }
-
-       return (u16) lv;
-}
-
-/*
- * This does LFSR conversion on the value that is to be written.
- * See LFSR explanation above for more detail.
- */
-static char *dlfb_set_register_lfsr16(char *wrptr, u8 reg, u16 value)
-{
-       return dlfb_set_register_16(wrptr, reg, dlfb_lfsr16(value));
-}
-
-/*
- * This takes a standard fbdev screeninfo struct and all of its monitor mode
- * details and converts them into the DisplayLink equivalent register commands.
- */
-static char *dlfb_set_vid_cmds(char *wrptr, struct fb_var_screeninfo *var)
-{
-       u16 xds, yds;
-       u16 xde, yde;
-       u16 yec;
-
-       /* x display start */
-       xds = var->left_margin + var->hsync_len;
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x01, xds);
-       /* x display end */
-       xde = xds + var->xres;
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x03, xde);
-
-       /* y display start */
-       yds = var->upper_margin + var->vsync_len;
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x05, yds);
-       /* y display end */
-       yde = yds + var->yres;
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x07, yde);
-
-       /* x end count is active + blanking - 1 */
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x09,
-                       xde + var->right_margin - 1);
-
-       /* libdlo hardcodes hsync start to 1 */
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x0B, 1);
-
-       /* hsync end is width of sync pulse + 1 */
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x0D, var->hsync_len + 1);
-
-       /* hpixels is active pixels */
-       wrptr = dlfb_set_register_16(wrptr, 0x0F, var->xres);
-
-       /* yendcount is vertical active + vertical blanking */
-       yec = var->yres + var->upper_margin + var->lower_margin +
-                       var->vsync_len;
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x11, yec);
-
-       /* libdlo hardcodes vsync start to 0 */
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x13, 0);
-
-       /* vsync end is width of vsync pulse */
-       wrptr = dlfb_set_register_lfsr16(wrptr, 0x15, var->vsync_len);
-
-       /* vpixels is active pixels */
-       wrptr = dlfb_set_register_16(wrptr, 0x17, var->yres);
-
-       /* convert picoseconds to 5kHz multiple for pclk5k = x * 1E12/5k */
-       wrptr = dlfb_set_register_16be(wrptr, 0x1B,
-                       200*1000*1000/var->pixclock);
-
-       return wrptr;
-}
-
-/*
- * This takes a standard fbdev screeninfo struct that was fetched or prepared
- * and then generates the appropriate command sequence that then drives the
- * display controller.
- */
-static int dlfb_set_video_mode(struct dlfb_data *dev,
-                               struct fb_var_screeninfo *var)
-{
-       char *buf;
-       char *wrptr;
-       int retval = 0;
-       int writesize;
-       struct urb *urb;
-
-       if (!atomic_read(&dev->usb_active))
-               return -EPERM;
-
-       urb = dlfb_get_urb(dev);
-       if (!urb)
-               return -ENOMEM;
-
-       buf = (char *) urb->transfer_buffer;
-
-       /*
-       * This first section has to do with setting the base address on the
-       * controller * associated with the display. There are 2 base
-       * pointers, currently, we only * use the 16 bpp segment.
-       */
-       wrptr = dlfb_vidreg_lock(buf);
-       wrptr = dlfb_set_color_depth(wrptr, 0x00);
-       /* set base for 16bpp segment to 0 */
-       wrptr = dlfb_set_base16bpp(wrptr, 0);
-       /* set base for 8bpp segment to end of fb */
-       wrptr = dlfb_set_base8bpp(wrptr, dev->info->fix.smem_len);
-
-       wrptr = dlfb_set_vid_cmds(wrptr, var);
-       wrptr = dlfb_enable_hvsync(wrptr, true);
-       wrptr = dlfb_vidreg_unlock(wrptr);
-
-       writesize = wrptr - buf;
-
-       retval = dlfb_submit_urb(dev, urb, writesize);
-
-       return retval;
-}
-
-static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)
-{
-       unsigned long start = vma->vm_start;
-       unsigned long size = vma->vm_end - vma->vm_start;
-       unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
-       unsigned long page, pos;
-
-       if (offset + size > info->fix.smem_len)
-               return -EINVAL;
-
-       pos = (unsigned long)info->fix.smem_start + offset;
-
-       dl_notice("mmap() framebuffer addr:%lu size:%lu\n",
-                 pos, size);
-
-       while (size > 0) {
-               page = vmalloc_to_pfn((void *)pos);
-               if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))
-                       return -EAGAIN;
-
-               start += PAGE_SIZE;
-               pos += PAGE_SIZE;
-               if (size > PAGE_SIZE)
-                       size -= PAGE_SIZE;
-               else
-                       size = 0;
-       }
-
-       vma->vm_flags |= VM_RESERVED;   /* avoid to swap out this VMA */
-       return 0;
-}
-
-/*
- * Trims identical data from front and back of line
- * Sets new front buffer address and width
- * And returns byte count of identical pixels
- * Assumes CPU natural alignment (unsigned long)
- * for back and front buffer ptrs and width
- */
-static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)
-{
-       int j, k;
-       const unsigned long *back = (const unsigned long *) bback;
-       const unsigned long *front = (const unsigned long *) *bfront;
-       const int width = *width_bytes / sizeof(unsigned long);
-       int identical = width;
-       int start = width;
-       int end = width;
-
-       prefetch((void *) front);
-       prefetch((void *) back);
-
-       for (j = 0; j < width; j++) {
-               if (back[j] != front[j]) {
-                       start = j;
-                       break;
-               }
-       }
-
-       for (k = width - 1; k > j; k--) {
-               if (back[k] != front[k]) {
-                       end = k+1;
-                       break;
-               }
-       }
-
-       identical = start + (width - end);
-       *bfront = (u8 *) &front[start];
-       *width_bytes = (end - start) * sizeof(unsigned long);
-
-       return identical * sizeof(unsigned long);
-}
-
-/*
- * Render a command stream for an encoded horizontal line segment of pixels.
- *
- * A command buffer holds several commands.
- * It always begins with a fresh command header
- * (the protocol doesn't require this, but we enforce it to allow
- * multiple buffers to be potentially encoded and sent in parallel).
- * A single command encodes one contiguous horizontal line of pixels
- *
- * The function relies on the client to do all allocation, so that
- * rendering can be done directly to output buffers (e.g. USB URBs).
- * The function fills the supplied command buffer, providing information
- * on where it left off, so the client may call in again with additional
- * buffers if the line will take several buffers to complete.
- *
- * A single command can transmit a maximum of 256 pixels,
- * regardless of the compression ratio (protocol design limit).
- * To the hardware, 0 for a size byte means 256
- *
- * Rather than 256 pixel commands which are either rl or raw encoded,
- * the rlx command simply assumes alternating raw and rl spans within one cmd.
- * This has a slightly larger header overhead, but produces more even results.
- * It also processes all data (read and write) in a single pass.
- * Performance benchmarks of common cases show it having just slightly better
- * compression than 256 pixel raw or rle commands, with similar CPU consumpion.
- * But for very rl friendly data, will compress not quite as well.
- */
-static void 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)
-{
-       const uint16_t *pixel = *pixel_start_ptr;
-       uint32_t dev_addr  = *device_address_ptr;
-       uint8_t *cmd = *command_buffer_ptr;
-       const int bpp = 2;
-
-       while ((pixel_end > pixel) &&
-              (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) {
-               uint8_t *raw_pixels_count_byte = 0;
-               uint8_t *cmd_pixels_count_byte = 0;
-               const uint16_t *raw_pixel_start = 0;
-               const uint16_t *cmd_pixel_start, *cmd_pixel_end = 0;
-
-               prefetchw((void *) cmd); /* pull in one cache line at least */
-
-               *cmd++ = 0xAF;
-               *cmd++ = 0x6B;
-               *cmd++ = (uint8_t) ((dev_addr >> 16) & 0xFF);
-               *cmd++ = (uint8_t) ((dev_addr >> 8) & 0xFF);
-               *cmd++ = (uint8_t) ((dev_addr) & 0xFF);
-
-               cmd_pixels_count_byte = cmd++; /*  we'll know this later */
-               cmd_pixel_start = pixel;
-
-               raw_pixels_count_byte = cmd++; /*  we'll know this later */
-               raw_pixel_start = pixel;
-
-               cmd_pixel_end = pixel + min(MAX_CMD_PIXELS + 1,
-                       min((int)(pixel_end - pixel),
-                           (int)(cmd_buffer_end - cmd) / bpp));
-
-               prefetch_range((void *) pixel, (cmd_pixel_end - pixel) * bpp);
-
-               while (pixel < cmd_pixel_end) {
-                       const uint16_t * const repeating_pixel = pixel;
-
-                       *(uint16_t *)cmd = cpu_to_be16p(pixel);
-                       cmd += 2;
-                       pixel++;
-
-                       if (unlikely((pixel < cmd_pixel_end) &&
-                                    (*pixel == *repeating_pixel))) {
-                               /* go back and fill in raw pixel count */
-                               *raw_pixels_count_byte = ((repeating_pixel -
-                                               raw_pixel_start) + 1) & 0xFF;
-
-                               while ((pixel < cmd_pixel_end)
-                                      && (*pixel == *repeating_pixel)) {
-                                       pixel++;
-                               }
-
-                               /* immediately after raw data is repeat byte */
-                               *cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF;
-
-                               /* Then start another raw pixel span */
-                               raw_pixel_start = pixel;
-                               raw_pixels_count_byte = cmd++;
-                       }
-               }
-
-               if (pixel > raw_pixel_start) {
-                       /* finalize last RAW span */
-                       *raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF;
-               }
-
-               *cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF;
-               dev_addr += (pixel - cmd_pixel_start) * bpp;
-       }
-
-       if (cmd_buffer_end <= MIN_RLX_CMD_BYTES + cmd) {
-               /* Fill leftover bytes with no-ops */
-               if (cmd_buffer_end > cmd)
-                       memset(cmd, 0xAF, cmd_buffer_end - cmd);
-               cmd = (uint8_t *) cmd_buffer_end;
-       }
-
-       *command_buffer_ptr = cmd;
-       *pixel_start_ptr = pixel;
-       *device_address_ptr = dev_addr;
-
-       return;
-}
-
-/*
- * There are 3 copies of every pixel: The front buffer that the fbdev
- * client renders to, the actual framebuffer across the USB bus in hardware
- * (that we can only write to, slowly, and can never read), and (optionally)
- * our shadow copy that tracks what's been sent to that hardware buffer.
- */
-static int dlfb_render_hline(struct dlfb_data *dev, struct urb **urb_ptr,
-                             const char *front, char **urb_buf_ptr,
-                             u32 byte_offset, u32 byte_width,
-                             int *ident_ptr, int *sent_ptr)
-{
-       const u8 *line_start, *line_end, *next_pixel;
-       u32 dev_addr = dev->base16 + byte_offset;
-       struct urb *urb = *urb_ptr;
-       u8 *cmd = *urb_buf_ptr;
-       u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length;
-
-       line_start = (u8 *) (front + byte_offset);
-       next_pixel = line_start;
-       line_end = next_pixel + byte_width;
-
-       if (dev->backing_buffer) {
-               int offset;
-               const u8 *back_start = (u8 *) (dev->backing_buffer
-                                               + byte_offset);
-
-               *ident_ptr += dlfb_trim_hline(back_start, &next_pixel,
-                       &byte_width);
-
-               offset = next_pixel - line_start;
-               line_end = next_pixel + byte_width;
-               dev_addr += offset;
-               back_start += offset;
-               line_start += offset;
-
-               memcpy((char *)back_start, (char *) line_start,
-                      byte_width);
-       }
-
-       while (next_pixel < line_end) {
-
-               dlfb_compress_hline((const uint16_t **) &next_pixel,
-                            (const uint16_t *) line_end, &dev_addr,
-                       (u8 **) &cmd, (u8 *) cmd_end);
-
-               if (cmd >= cmd_end) {
-                       int len = cmd - (u8 *) urb->transfer_buffer;
-                       if (dlfb_submit_urb(dev, urb, len))
-                               return 1; /* lost pixels is set */
-                       *sent_ptr += len;
-                       urb = dlfb_get_urb(dev);
-                       if (!urb)
-                               return 1; /* lost_pixels is set */
-                       *urb_ptr = urb;
-                       cmd = urb->transfer_buffer;
-                       cmd_end = &cmd[urb->transfer_buffer_length];
-               }
-       }
-
-       *urb_buf_ptr = cmd;
-
-       return 0;
-}
-
-int dlfb_handle_damage(struct dlfb_data *dev, int x, int y,
-              int width, int height, char *data)
-{
-       int i, ret;
-       char *cmd;
-       cycles_t start_cycles, end_cycles;
-       int bytes_sent = 0;
-       int bytes_identical = 0;
-       struct urb *urb;
-       int aligned_x;
-
-       start_cycles = get_cycles();
-
-       aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long));
-       width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long));
-       x = aligned_x;
-
-       if ((width <= 0) ||
-           (x + width > dev->info->var.xres) ||
-           (y + height > dev->info->var.yres))
-               return -EINVAL;
-
-       if (!atomic_read(&dev->usb_active))
-               return 0;
-
-       urb = dlfb_get_urb(dev);
-       if (!urb)
-               return 0;
-       cmd = urb->transfer_buffer;
-
-       for (i = y; i < y + height ; i++) {
-               const int line_offset = dev->info->fix.line_length * i;
-               const int byte_offset = line_offset + (x * BPP);
-
-               if (dlfb_render_hline(dev, &urb,
-                                     (char *) dev->info->fix.smem_start,
-                                     &cmd, byte_offset, width * BPP,
-                                     &bytes_identical, &bytes_sent))
-                       goto error;
-       }
-
-       if (cmd > (char *) urb->transfer_buffer) {
-               /* Send partial buffer remaining before exiting */
-               int len = cmd - (char *) urb->transfer_buffer;
-               ret = dlfb_submit_urb(dev, urb, len);
-               bytes_sent += len;
-       } else
-               dlfb_urb_completion(urb);
-
-error:
-       atomic_add(bytes_sent, &dev->bytes_sent);
-       atomic_add(bytes_identical, &dev->bytes_identical);
-       atomic_add(width*height*2, &dev->bytes_rendered);
-       end_cycles = get_cycles();
-       atomic_add(((unsigned int) ((end_cycles - start_cycles)
-                   >> 10)), /* Kcycles */
-                  &dev->cpu_kcycles_used);
-
-       return 0;
-}
-
-static ssize_t dlfb_ops_read(struct fb_info *info, char __user *buf,
-                        size_t count, loff_t *ppos)
-{
-       ssize_t result = -ENOSYS;
-
-#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
-       result = fb_sys_read(info, buf, count, ppos);
-#endif
-
-       return result;
-}
-
-/*
- * Path triggered by usermode clients who write to filesystem
- * e.g. cat filename > /dev/fb1
- * Not used by X Windows or text-mode console. But useful for testing.
- * Slow because of extra copy and we must assume all pixels dirty.
- */
-static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
-                         size_t count, loff_t *ppos)
-{
-       ssize_t result = -ENOSYS;
-       struct dlfb_data *dev = info->par;
-       u32 offset = (u32) *ppos;
-
-#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
-
-       result = fb_sys_write(info, buf, count, ppos);
-
-       if (result > 0) {
-               int start = max((int)(offset / info->fix.line_length) - 1, 0);
-               int lines = min((u32)((result / info->fix.line_length) + 1),
-                               (u32)info->var.yres);
-
-               dlfb_handle_damage(dev, 0, start, info->var.xres,
-                       lines, info->screen_base);
-       }
-#endif
-
-       return result;
-}
-
-/* hardware has native COPY command (see libdlo), but not worth it for fbcon */
-static void dlfb_ops_copyarea(struct fb_info *info,
-                               const struct fb_copyarea *area)
-{
-
-       struct dlfb_data *dev = info->par;
-
-#if defined CONFIG_FB_SYS_COPYAREA || defined CONFIG_FB_SYS_COPYAREA_MODULE
-
-       sys_copyarea(info, area);
-
-       dlfb_handle_damage(dev, area->dx, area->dy,
-                       area->width, area->height, info->screen_base);
-#endif
-
-}
-
-static void dlfb_ops_imageblit(struct fb_info *info,
-                               const struct fb_image *image)
-{
-       struct dlfb_data *dev = info->par;
-
-#if defined CONFIG_FB_SYS_IMAGEBLIT || defined CONFIG_FB_SYS_IMAGEBLIT_MODULE
-
-       sys_imageblit(info, image);
-
-       dlfb_handle_damage(dev, image->dx, image->dy,
-                       image->width, image->height, info->screen_base);
-
-#endif
-
-}
-
-static void dlfb_ops_fillrect(struct fb_info *info,
-                         const struct fb_fillrect *rect)
-{
-       struct dlfb_data *dev = info->par;
-
-#if defined CONFIG_FB_SYS_FILLRECT || defined CONFIG_FB_SYS_FILLRECT_MODULE
-
-       sys_fillrect(info, rect);
-
-       dlfb_handle_damage(dev, rect->dx, rect->dy, rect->width,
-                             rect->height, info->screen_base);
-#endif
-
-}
-
-#ifdef CONFIG_FB_DEFERRED_IO
-/*
- * NOTE: fb_defio.c is holding info->fbdefio.mutex
- *   Touching ANY framebuffer memory that triggers a page fault
- *   in fb_defio will cause a deadlock, when it also tries to
- *   grab the same mutex.
- */
-static void dlfb_dpy_deferred_io(struct fb_info *info,
-                               struct list_head *pagelist)
-{
-       struct page *cur;
-       struct fb_deferred_io *fbdefio = info->fbdefio;
-       struct dlfb_data *dev = info->par;
-       struct urb *urb;
-       char *cmd;
-       cycles_t start_cycles, end_cycles;
-       int bytes_sent = 0;
-       int bytes_identical = 0;
-       int bytes_rendered = 0;
-
-       if (!fb_defio)
-               return;
-
-       if (!atomic_read(&dev->usb_active))
-               return;
-
-       start_cycles = get_cycles();
-
-       urb = dlfb_get_urb(dev);
-       if (!urb)
-               return;
-
-       cmd = urb->transfer_buffer;
-
-       /* walk the written page list and render each to device */
-       list_for_each_entry(cur, &fbdefio->pagelist, lru) {
-
-               if (dlfb_render_hline(dev, &urb, (char *) info->fix.smem_start,
-                                 &cmd, cur->index << PAGE_SHIFT,
-                                 PAGE_SIZE, &bytes_identical, &bytes_sent))
-                       goto error;
-               bytes_rendered += PAGE_SIZE;
-       }
-
-       if (cmd > (char *) urb->transfer_buffer) {
-               /* Send partial buffer remaining before exiting */
-               int len = cmd - (char *) urb->transfer_buffer;
-               dlfb_submit_urb(dev, urb, len);
-               bytes_sent += len;
-       } else
-               dlfb_urb_completion(urb);
-
-error:
-       atomic_add(bytes_sent, &dev->bytes_sent);
-       atomic_add(bytes_identical, &dev->bytes_identical);
-       atomic_add(bytes_rendered, &dev->bytes_rendered);
-       end_cycles = get_cycles();
-       atomic_add(((unsigned int) ((end_cycles - start_cycles)
-                   >> 10)), /* Kcycles */
-                  &dev->cpu_kcycles_used);
-}
-
-#endif
-
-static int dlfb_get_edid(struct dlfb_data *dev, char *edid, int len)
-{
-       int i;
-       int ret;
-       char *rbuf;
-
-       rbuf = kmalloc(2, GFP_KERNEL);
-       if (!rbuf)
-               return 0;
-
-       for (i = 0; i < len; i++) {
-               ret = usb_control_msg(dev->udev,
-                                   usb_rcvctrlpipe(dev->udev, 0), (0x02),
-                                   (0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2,
-                                   HZ);
-               if (ret < 1) {
-                       dl_err("Read EDID byte %d failed err %x\n", i, ret);
-                       i--;
-                       break;
-               }
-               edid[i] = rbuf[1];
-       }
-
-       kfree(rbuf);
-
-       return i;
-}
-
-static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd,
-                               unsigned long arg)
-{
-
-       struct dlfb_data *dev = info->par;
-       struct dloarea *area = NULL;
-
-       if (!atomic_read(&dev->usb_active))
-               return 0;
-
-       /* TODO: Update X server to get this from sysfs instead */
-       if (cmd == DLFB_IOCTL_RETURN_EDID) {
-               char *edid = (char *)arg;
-               if (copy_to_user(edid, dev->edid, dev->edid_size))
-                       return -EFAULT;
-               return 0;
-       }
-
-       /* TODO: Help propose a standard fb.h ioctl to report mmap damage */
-       if (cmd == DLFB_IOCTL_REPORT_DAMAGE) {
-
-               /*
-                * If we have a damage-aware client, turn fb_defio "off"
-                * To avoid perf imact of unecessary page fault handling.
-                * Done by resetting the delay for this fb_info to a very
-                * long period. Pages will become writable and stay that way.
-                * Reset to normal value when all clients have closed this fb.
-                */
-               if (info->fbdefio)
-                       info->fbdefio->delay = DL_DEFIO_WRITE_DISABLE;
-
-               area = (struct dloarea *)arg;
-
-               if (area->x < 0)
-                       area->x = 0;
-
-               if (area->x > info->var.xres)
-                       area->x = info->var.xres;
-
-               if (area->y < 0)
-                       area->y = 0;
-
-               if (area->y > info->var.yres)
-                       area->y = info->var.yres;
-
-               dlfb_handle_damage(dev, area->x, area->y, area->w, area->h,
-                          info->screen_base);
-       }
-
-       return 0;
-}
-
-/* taken from vesafb */
-static int
-dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green,
-              unsigned blue, unsigned transp, struct fb_info *info)
-{
-       int err = 0;
-
-       if (regno >= info->cmap.len)
-               return 1;
-
-       if (regno < 16) {
-               if (info->var.red.offset == 10) {
-                       /* 1:5:5:5 */
-                       ((u32 *) (info->pseudo_palette))[regno] =
-                           ((red & 0xf800) >> 1) |
-                           ((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11);
-               } else {
-                       /* 0:5:6:5 */
-                       ((u32 *) (info->pseudo_palette))[regno] =
-                           ((red & 0xf800)) |
-                           ((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11);
-               }
-       }
-
-       return err;
-}
-
-/*
- * It's common for several clients to have framebuffer open simultaneously.
- * e.g. both fbcon and X. Makes things interesting.
- * Assumes caller is holding info->lock (for open and release at least)
- */
-static int dlfb_ops_open(struct fb_info *info, int user)
-{
-       struct dlfb_data *dev = info->par;
-
-       /*
-        * fbcon aggressively connects to first framebuffer it finds,
-        * preventing other clients (X) from working properly. Usually
-        * not what the user wants. Fail by default with option to enable.
-        */
-       if ((user == 0) & (!console))
-               return -EBUSY;
-
-       /* If the USB device is gone, we don't accept new opens */
-       if (dev->virtualized)
-               return -ENODEV;
-
-       dev->fb_count++;
-
-       kref_get(&dev->kref);
-
-#ifdef CONFIG_FB_DEFERRED_IO
-       if (fb_defio && (info->fbdefio == NULL)) {
-               /* enable defio at last moment if not disabled by client */
-
-               struct fb_deferred_io *fbdefio;
-
-               fbdefio = kmalloc(sizeof(struct fb_deferred_io), GFP_KERNEL);
-
-               if (fbdefio) {
-                       fbdefio->delay = DL_DEFIO_WRITE_DELAY;
-                       fbdefio->deferred_io = dlfb_dpy_deferred_io;
-               }
-
-               info->fbdefio = fbdefio;
-               fb_deferred_io_init(info);
-       }
-#endif
-
-       dl_notice("open /dev/fb%d user=%d fb_info=%p count=%d\n",
-           info->node, user, info, dev->fb_count);
-
-       return 0;
-}
-
-/*
- * Called when all client interfaces to start transactions have been disabled,
- * and all references to our device instance (dlfb_data) are released.
- * Every transaction must have a reference, so we know are fully spun down
- */
-static void dlfb_free(struct kref *kref)
-{
-       struct dlfb_data *dev = container_of(kref, struct dlfb_data, kref);
-
-       /* this function will wait for all in-flight urbs to complete */
-       if (dev->urbs.count > 0)
-               dlfb_free_urb_list(dev);
-
-       if (dev->backing_buffer)
-               vfree(dev->backing_buffer);
-
-       kfree(dev->edid);
-
-       dl_warn("freeing dlfb_data %p\n", dev);
-
-       kfree(dev);
-}
-
-static void dlfb_release_urb_work(struct work_struct *work)
-{
-       struct urb_node *unode = container_of(work, struct urb_node,
-                                             release_urb_work.work);
-
-       up(&unode->dev->urbs.limit_sem);
-}
-
-static void dlfb_free_framebuffer_work(struct work_struct *work)
-{
-       struct dlfb_data *dev = container_of(work, struct dlfb_data,
-                                            free_framebuffer_work.work);
-       struct fb_info *info = dev->info;
-       int node = info->node;
-
-       unregister_framebuffer(info);
-
-       if (info->cmap.len != 0)
-               fb_dealloc_cmap(&info->cmap);
-       if (info->monspecs.modedb)
-               fb_destroy_modedb(info->monspecs.modedb);
-       if (info->screen_base)
-               vfree(info->screen_base);
-
-       fb_destroy_modelist(&info->modelist);
-
-       dev->info = 0;
-
-       /* Assume info structure is freed after this point */
-       framebuffer_release(info);
-
-       dl_warn("fb_info for /dev/fb%d has been freed\n", node);
-
-       /* ref taken in probe() as part of registering framebfufer */
-       kref_put(&dev->kref, dlfb_free);
-}
-
-/*
- * Assumes caller is holding info->lock mutex (for open and release at least)
- */
-static int dlfb_ops_release(struct fb_info *info, int user)
-{
-       struct dlfb_data *dev = info->par;
-
-       dev->fb_count--;
-
-       /* We can't free fb_info here - fbmem will touch it when we return */
-       if (dev->virtualized && (dev->fb_count == 0))
-               schedule_delayed_work(&dev->free_framebuffer_work, HZ);
-
-#ifdef CONFIG_FB_DEFERRED_IO
-       if ((dev->fb_count == 0) && (info->fbdefio)) {
-               fb_deferred_io_cleanup(info);
-               kfree(info->fbdefio);
-               info->fbdefio = NULL;
-               info->fbops->fb_mmap = dlfb_ops_mmap;
-       }
-#endif
-
-       dl_warn("released /dev/fb%d user=%d count=%d\n",
-                 info->node, user, dev->fb_count);
-
-       kref_put(&dev->kref, dlfb_free);
-
-       return 0;
-}
-
-/*
- * Check whether a video mode is supported by the DisplayLink chip
- * We start from monitor's modes, so don't need to filter that here
- */
-static int dlfb_is_valid_mode(struct fb_videomode *mode,
-               struct fb_info *info)
-{
-       struct dlfb_data *dev = info->par;
-
-       if (mode->xres * mode->yres > dev->sku_pixel_limit) {
-               dl_warn("%dx%d beyond chip capabilities\n",
-                      mode->xres, mode->yres);
-               return 0;
-       }
-
-       dl_info("%dx%d valid mode\n", mode->xres, mode->yres);
-
-       return 1;
-}
-
-static void dlfb_var_color_format(struct fb_var_screeninfo *var)
-{
-       const struct fb_bitfield red = { 11, 5, 0 };
-       const struct fb_bitfield green = { 5, 6, 0 };
-       const struct fb_bitfield blue = { 0, 5, 0 };
-
-       var->bits_per_pixel = 16;
-       var->red = red;
-       var->green = green;
-       var->blue = blue;
-}
-
-static int dlfb_ops_check_var(struct fb_var_screeninfo *var,
-                               struct fb_info *info)
-{
-       struct fb_videomode mode;
-
-       /* TODO: support dynamically changing framebuffer size */
-       if ((var->xres * var->yres * 2) > info->fix.smem_len)
-               return -EINVAL;
-
-       /* set device-specific elements of var unrelated to mode */
-       dlfb_var_color_format(var);
-
-       fb_var_to_videomode(&mode, var);
-
-       if (!dlfb_is_valid_mode(&mode, info))
-               return -EINVAL;
-
-       return 0;
-}
-
-static int dlfb_ops_set_par(struct fb_info *info)
-{
-       struct dlfb_data *dev = info->par;
-       int result;
-       u16 *pix_framebuffer;
-       int i;
-
-       dl_notice("set_par mode %dx%d\n", info->var.xres, info->var.yres);
-
-       result = dlfb_set_video_mode(dev, &info->var);
-
-       if ((result == 0) && (dev->fb_count == 0)) {
-
-               /* paint greenscreen */
-
-               pix_framebuffer = (u16 *) info->screen_base;
-               for (i = 0; i < info->fix.smem_len / 2; i++)
-                       pix_framebuffer[i] = 0x37e6;
-
-               dlfb_handle_damage(dev, 0, 0, info->var.xres, info->var.yres,
-                                  info->screen_base);
-       }
-
-       return result;
-}
-
-/*
- * In order to come back from full DPMS off, we need to set the mode again
- */
-static int dlfb_ops_blank(int blank_mode, struct fb_info *info)
-{
-       struct dlfb_data *dev = info->par;
-
-       if (blank_mode != FB_BLANK_UNBLANK) {
-               char *bufptr;
-               struct urb *urb;
-
-               urb = dlfb_get_urb(dev);
-               if (!urb)
-                       return 0;
-
-               bufptr = (char *) urb->transfer_buffer;
-               bufptr = dlfb_vidreg_lock(bufptr);
-               bufptr = dlfb_enable_hvsync(bufptr, false);
-               bufptr = dlfb_vidreg_unlock(bufptr);
-
-               dlfb_submit_urb(dev, urb, bufptr -
-                               (char *) urb->transfer_buffer);
-       } else {
-               dlfb_set_video_mode(dev, &info->var);
-       }
-
-       return 0;
-}
-
-static struct fb_ops dlfb_ops = {
-       .owner = THIS_MODULE,
-       .fb_read = dlfb_ops_read,
-       .fb_write = dlfb_ops_write,
-       .fb_setcolreg = dlfb_ops_setcolreg,
-       .fb_fillrect = dlfb_ops_fillrect,
-       .fb_copyarea = dlfb_ops_copyarea,
-       .fb_imageblit = dlfb_ops_imageblit,
-       .fb_mmap = dlfb_ops_mmap,
-       .fb_ioctl = dlfb_ops_ioctl,
-       .fb_open = dlfb_ops_open,
-       .fb_release = dlfb_ops_release,
-       .fb_blank = dlfb_ops_blank,
-       .fb_check_var = dlfb_ops_check_var,
-       .fb_set_par = dlfb_ops_set_par,
-};
-
-
-/*
- * Assumes &info->lock held by caller
- * Assumes no active clients have framebuffer open
- */
-static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info)
-{
-       int retval = -ENOMEM;
-       int old_len = info->fix.smem_len;
-       int new_len;
-       unsigned char *old_fb = info->screen_base;
-       unsigned char *new_fb;
-       unsigned char *new_back;
-
-       dl_warn("Reallocating framebuffer. Addresses will change!\n");
-
-       new_len = info->fix.line_length * info->var.yres;
-
-       if (PAGE_ALIGN(new_len) > old_len) {
-               /*
-                * Alloc system memory for virtual framebuffer
-                */
-               new_fb = vmalloc(new_len);
-               if (!new_fb) {
-                       dl_err("Virtual framebuffer alloc failed\n");
-                       goto error;
-               }
-
-               if (info->screen_base) {
-                       memcpy(new_fb, old_fb, old_len);
-                       vfree(info->screen_base);
-               }
-
-               info->screen_base = new_fb;
-               info->fix.smem_len = PAGE_ALIGN(new_len);
-               info->fix.smem_start = (unsigned long) new_fb;
-               info->flags = udlfb_info_flags;
-
-               /*
-                * Second framebuffer copy to mirror the framebuffer state
-                * on the physical USB device. We can function without this.
-                * But with imperfect damage info we may send pixels over USB
-                * that were, in fact, unchanged - wasting limited USB bandwidth
-                */
-               new_back = vmalloc(new_len);
-               if (!new_back)
-                       dl_info("No shadow/backing buffer allcoated\n");
-               else {
-                       if (dev->backing_buffer)
-                               vfree(dev->backing_buffer);
-                       dev->backing_buffer = new_back;
-                       memset(dev->backing_buffer, 0, new_len);
-               }
-       }
-
-       retval = 0;
-
-error:
-       return retval;
-}
-
-/*
- * 1) Get EDID from hw, or use sw default
- * 2) Parse into various fb_info structs
- * 3) Allocate virtual framebuffer memory to back highest res mode
- *
- * Parses EDID into three places used by various parts of fbdev:
- * fb_var_screeninfo contains the timing of the monitor's preferred mode
- * fb_info.monspecs is full parsed EDID info, including monspecs.modedb
- * fb_info.modelist is a linked list of all monitor & VESA modes which work
- *
- * If EDID is not readable/valid, then modelist is all VESA modes,
- * monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode
- * Returns 0 if successful
- */
-static int dlfb_setup_modes(struct dlfb_data *dev,
-                          struct fb_info *info,
-                          char *default_edid, size_t default_edid_size)
-{
-       int i;
-       const struct fb_videomode *default_vmode = NULL;
-       int result = 0;
-       char *edid;
-       int tries = 3;
-
-       if (info->dev) /* only use mutex if info has been registered */
-               mutex_lock(&info->lock);
-
-       edid = kmalloc(MAX_EDID_SIZE, GFP_KERNEL);
-       if (!edid) {
-               result = -ENOMEM;
-               goto error;
-       }
-
-       fb_destroy_modelist(&info->modelist);
-       memset(&info->monspecs, 0, sizeof(info->monspecs));
-
-       /*
-        * Try to (re)read EDID from hardware first
-        * EDID data may return, but not parse as valid
-        * Try again a few times, in case of e.g. analog cable noise
-        */
-       while (tries--) {
-
-               i = dlfb_get_edid(dev, edid, MAX_EDID_SIZE);
-
-               if (i >= MIN_EDID_SIZE)
-                       fb_edid_to_monspecs(edid, &info->monspecs);
-
-               if (info->monspecs.modedb_len > 0) {
-                       dev->edid = edid;
-                       dev->edid_size = i;
-                       break;
-               }
-       }
-
-       /* If that fails, use a previously returned EDID if available */
-       if (info->monspecs.modedb_len == 0) {
-
-               dl_err("Unable to get valid EDID from device/display\n");
-
-               if (dev->edid) {
-                       fb_edid_to_monspecs(dev->edid, &info->monspecs);
-                       if (info->monspecs.modedb_len > 0)
-                               dl_err("Using previously queried EDID\n");
-               }
-       }
-
-       /* If that fails, use the default EDID we were handed */
-       if (info->monspecs.modedb_len == 0) {
-               if (default_edid_size >= MIN_EDID_SIZE) {
-                       fb_edid_to_monspecs(default_edid, &info->monspecs);
-                       if (info->monspecs.modedb_len > 0) {
-                               memcpy(edid, default_edid, default_edid_size);
-                               dev->edid = edid;
-                               dev->edid_size = default_edid_size;
-                               dl_err("Using default/backup EDID\n");
-                       }
-               }
-       }
-
-       /* If we've got modes, let's pick a best default mode */
-       if (info->monspecs.modedb_len > 0) {
-
-               for (i = 0; i < info->monspecs.modedb_len; i++) {
-                       if (dlfb_is_valid_mode(&info->monspecs.modedb[i], info))
-                               fb_add_videomode(&info->monspecs.modedb[i],
-                                       &info->modelist);
-                       else /* if we've removed top/best mode */
-                               info->monspecs.misc &= ~FB_MISC_1ST_DETAIL;
-               }
-
-               default_vmode = fb_find_best_display(&info->monspecs,
-                                                    &info->modelist);
-       }
-
-       /* If everything else has failed, fall back to safe default mode */
-       if (default_vmode == NULL) {
-
-               struct fb_videomode fb_vmode = {0};
-
-               /*
-                * Add the standard VESA modes to our modelist
-                * Since we don't have EDID, there may be modes that
-                * overspec monitor and/or are incorrect aspect ratio, etc.
-                * But at least the user has a chance to choose
-                */
-               for (i = 0; i < VESA_MODEDB_SIZE; i++) {
-                       if (dlfb_is_valid_mode((struct fb_videomode *)
-                                               &vesa_modes[i], info))
-                               fb_add_videomode(&vesa_modes[i],
-                                                &info->modelist);
-               }
-
-               /*
-                * default to resolution safe for projectors
-                * (since they are most common case without EDID)
-                */
-               fb_vmode.xres = 800;
-               fb_vmode.yres = 600;
-               fb_vmode.refresh = 60;
-               default_vmode = fb_find_nearest_mode(&fb_vmode,
-                                                    &info->modelist);
-       }
-
-       /* If we have good mode and no active clients*/
-       if ((default_vmode != NULL) && (dev->fb_count == 0)) {
-
-               fb_videomode_to_var(&info->var, default_vmode);
-               dlfb_var_color_format(&info->var);
-
-               /*
-                * with mode size info, we can now alloc our framebuffer.
-                */
-               memcpy(&info->fix, &dlfb_fix, sizeof(dlfb_fix));
-               info->fix.line_length = info->var.xres *
-                       (info->var.bits_per_pixel / 8);
-
-               result = dlfb_realloc_framebuffer(dev, info);
-
-       } else
-               result = -EINVAL;
-
-error:
-       if (edid && (dev->edid != edid))
-               kfree(edid);
-
-       if (info->dev)
-               mutex_unlock(&info->lock);
-
-       return result;
-}
-
-static ssize_t metrics_bytes_rendered_show(struct device *fbdev,
-                                  struct device_attribute *a, char *buf) {
-       struct fb_info *fb_info = dev_get_drvdata(fbdev);
-       struct dlfb_data *dev = fb_info->par;
-       return snprintf(buf, PAGE_SIZE, "%u\n",
-                       atomic_read(&dev->bytes_rendered));
-}
-
-static ssize_t metrics_bytes_identical_show(struct device *fbdev,
-                                  struct device_attribute *a, char *buf) {
-       struct fb_info *fb_info = dev_get_drvdata(fbdev);
-       struct dlfb_data *dev = fb_info->par;
-       return snprintf(buf, PAGE_SIZE, "%u\n",
-                       atomic_read(&dev->bytes_identical));
-}
-
-static ssize_t metrics_bytes_sent_show(struct device *fbdev,
-                                  struct device_attribute *a, char *buf) {
-       struct fb_info *fb_info = dev_get_drvdata(fbdev);
-       struct dlfb_data *dev = fb_info->par;
-       return snprintf(buf, PAGE_SIZE, "%u\n",
-                       atomic_read(&dev->bytes_sent));
-}
-
-static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev,
-                                  struct device_attribute *a, char *buf) {
-       struct fb_info *fb_info = dev_get_drvdata(fbdev);
-       struct dlfb_data *dev = fb_info->par;
-       return snprintf(buf, PAGE_SIZE, "%u\n",
-                       atomic_read(&dev->cpu_kcycles_used));
-}
-
-static ssize_t edid_show(
-                       struct file *filp,
-                       struct kobject *kobj, struct bin_attribute *a,
-                        char *buf, loff_t off, size_t count) {
-       struct device *fbdev = container_of(kobj, struct device, kobj);
-       struct fb_info *fb_info = dev_get_drvdata(fbdev);
-       struct dlfb_data *dev = fb_info->par;
-
-       if (dev->edid == NULL)
-               return 0;
-
-       if ((off >= dev->edid_size) || (count > dev->edid_size))
-               return 0;
-
-       if (off + count > dev->edid_size)
-               count = dev->edid_size - off;
-
-       dl_info("sysfs edid copy %p to %p, %d bytes\n",
-               dev->edid, buf, (int) count);
-
-       memcpy(buf, dev->edid, count);
-
-       return count;
-}
-
-static ssize_t edid_store(
-                       struct file *filp,
-                       struct kobject *kobj, struct bin_attribute *a,
-                       char *src, loff_t src_off, size_t src_size) {
-       struct device *fbdev = container_of(kobj, struct device, kobj);
-       struct fb_info *fb_info = dev_get_drvdata(fbdev);
-       struct dlfb_data *dev = fb_info->par;
-
-       /* We only support write of entire EDID at once, no offset*/
-       if ((src_size < MIN_EDID_SIZE) ||
-           (src_size > MAX_EDID_SIZE) ||
-           (src_off != 0))
-               return 0;
-
-       dlfb_setup_modes(dev, fb_info, src, src_size);
-
-       if (dev->edid && (memcmp(src, dev->edid, src_size) == 0)) {
-               dl_info("sysfs written EDID is new default\n");
-               dlfb_ops_set_par(fb_info);
-               return src_size;
-       } else
-               return 0;
-}
-
-static ssize_t metrics_reset_store(struct device *fbdev,
-                          struct device_attribute *attr,
-                          const char *buf, size_t count)
-{
-       struct fb_info *fb_info = dev_get_drvdata(fbdev);
-       struct dlfb_data *dev = fb_info->par;
-
-       atomic_set(&dev->bytes_rendered, 0);
-       atomic_set(&dev->bytes_identical, 0);
-       atomic_set(&dev->bytes_sent, 0);
-       atomic_set(&dev->cpu_kcycles_used, 0);
-
-       return count;
-}
-
-static struct bin_attribute edid_attr = {
-       .attr.name = "edid",
-       .attr.mode = 0666,
-       .size = MAX_EDID_SIZE,
-       .read = edid_show,
-       .write = edid_store
-};
-
-static struct device_attribute fb_device_attrs[] = {
-       __ATTR_RO(metrics_bytes_rendered),
-       __ATTR_RO(metrics_bytes_identical),
-       __ATTR_RO(metrics_bytes_sent),
-       __ATTR_RO(metrics_cpu_kcycles_used),
-       __ATTR(metrics_reset, S_IWUGO, NULL, metrics_reset_store),
-};
-
-/*
- * This is necessary before we can communicate with the display controller.
- */
-static int dlfb_select_std_channel(struct dlfb_data *dev)
-{
-       int ret;
-       u8 set_def_chn[] = {       0x57, 0xCD, 0xDC, 0xA7,
-                               0x1C, 0x88, 0x5E, 0x15,
-                               0x60, 0xFE, 0xC6, 0x97,
-                               0x16, 0x3D, 0x47, 0xF2  };
-
-       ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
-                       NR_USB_REQUEST_CHANNEL,
-                       (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
-                       set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT);
-       return ret;
-}
-
-static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
-                                       struct usb_device *usbdev)
-{
-       char *desc;
-       char *buf;
-       char *desc_end;
-
-       u8 total_len = 0;
-
-       buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);
-       if (!buf)
-               return false;
-       desc = buf;
-
-       total_len = usb_get_descriptor(usbdev, 0x5f, /* vendor specific */
-                                   0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
-       if (total_len > 5) {
-               dl_info("vendor descriptor length:%x data:%02x %02x %02x %02x" \
-                       "%02x %02x %02x %02x %02x %02x %02x\n",
-                       total_len, desc[0],
-                       desc[1], desc[2], desc[3], desc[4], desc[5], desc[6],
-                       desc[7], desc[8], desc[9], desc[10]);
-
-               if ((desc[0] != total_len) || /* descriptor length */
-                   (desc[1] != 0x5f) ||   /* vendor descriptor type */
-                   (desc[2] != 0x01) ||   /* version (2 bytes) */
-                   (desc[3] != 0x00) ||
-                   (desc[4] != total_len - 2)) /* length after type */
-                       goto unrecognized;
-
-               desc_end = desc + total_len;
-               desc += 5; /* the fixed header we've already parsed */
-
-               while (desc < desc_end) {
-                       u8 length;
-                       u16 key;
-
-                       key = *((u16 *) desc);
-                       desc += sizeof(u16);
-                       length = *desc;
-                       desc++;
-
-                       switch (key) {
-                       case 0x0200: { /* max_area */
-                               u32 max_area;
-                               max_area = le32_to_cpu(*((u32 *)desc));
-                               dl_warn("DL chip limited to %d pixel modes\n",
-                                       max_area);
-                               dev->sku_pixel_limit = max_area;
-                               break;
-                       }
-                       default:
-                               break;
-                       }
-                       desc += length;
-               }
-       }
-
-       goto success;
-
-unrecognized:
-       /* allow udlfb to load for now even if firmware unrecognized */
-       dl_err("Unrecognized vendor firmware descriptor\n");
-
-success:
-       kfree(buf);
-       return true;
-}
-static int dlfb_usb_probe(struct usb_interface *interface,
-                       const struct usb_device_id *id)
-{
-       struct usb_device *usbdev;
-       struct dlfb_data *dev = 0;
-       struct fb_info *info = 0;
-       int retval = -ENOMEM;
-       int i;
-
-       /* usb initialization */
-
-       usbdev = interface_to_usbdev(interface);
-
-       dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-       if (dev == NULL) {
-               err("dlfb_usb_probe: failed alloc of dev struct\n");
-               goto error;
-       }
-
-       /* we need to wait for both usb and fbdev to spin down on disconnect */
-       kref_init(&dev->kref); /* matching kref_put in usb .disconnect fn */
-       kref_get(&dev->kref); /* matching kref_put in free_framebuffer_work */
-
-       dev->udev = usbdev;
-       dev->gdev = &usbdev->dev; /* our generic struct device * */
-       usb_set_intfdata(interface, dev);
-
-       dl_info("%s %s - serial #%s\n",
-               usbdev->manufacturer, usbdev->product, usbdev->serial);
-       dl_info("vid_%04x&pid_%04x&rev_%04x driver's dlfb_data struct at %p\n",
-               usbdev->descriptor.idVendor, usbdev->descriptor.idProduct,
-               usbdev->descriptor.bcdDevice, dev);
-       dl_info("console enable=%d\n", console);
-       dl_info("fb_defio enable=%d\n", fb_defio);
-
-       dev->sku_pixel_limit = 2048 * 1152; /* default to maximum */
-
-       if (!dlfb_parse_vendor_descriptor(dev, usbdev)) {
-               dl_err("firmware not recognized. Assume incompatible device\n");
-               goto error;
-       }
-
-       if (!dlfb_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
-               retval = -ENOMEM;
-               dl_err("dlfb_alloc_urb_list failed\n");
-               goto error;
-       }
-
-       /* We don't register a new USB class. Our client interface is fbdev */
-
-       /* allocates framebuffer driver structure, not framebuffer memory */
-       info = framebuffer_alloc(0, &usbdev->dev);
-       if (!info) {
-               retval = -ENOMEM;
-               dl_err("framebuffer_alloc failed\n");
-               goto error;
-       }
-
-       dev->info = info;
-       info->par = dev;
-       info->pseudo_palette = dev->pseudo_palette;
-       info->fbops = &dlfb_ops;
-
-       retval = fb_alloc_cmap(&info->cmap, 256, 0);
-       if (retval < 0) {
-               dl_err("fb_alloc_cmap failed %x\n", retval);
-               goto error;
-       }
-
-       INIT_DELAYED_WORK(&dev->free_framebuffer_work,
-                         dlfb_free_framebuffer_work);
-
-       INIT_LIST_HEAD(&info->modelist);
-
-       retval = dlfb_setup_modes(dev, info, NULL, 0);
-       if (retval != 0) {
-               dl_err("unable to find common mode for display and adapter\n");
-               goto error;
-       }
-
-       /* ready to begin using device */
-
-       atomic_set(&dev->usb_active, 1);
-       dlfb_select_std_channel(dev);
-
-       dlfb_ops_check_var(&info->var, info);
-       dlfb_ops_set_par(info);
-
-       retval = register_framebuffer(info);
-       if (retval < 0) {
-               dl_err("register_framebuffer failed %d\n", retval);
-               goto error;
-       }
-
-       for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
-               device_create_file(info->dev, &fb_device_attrs[i]);
-
-       device_create_bin_file(info->dev, &edid_attr);
-
-       dl_info("DisplayLink USB device /dev/fb%d attached. %dx%d resolution."
-                       " Using %dK framebuffer memory\n", info->node,
-                       info->var.xres, info->var.yres,
-                       ((dev->backing_buffer) ?
-                       info->fix.smem_len * 2 : info->fix.smem_len) >> 10);
-       return 0;
-
-error:
-       if (dev) {
-
-               if (info) {
-                       if (info->cmap.len != 0)
-                               fb_dealloc_cmap(&info->cmap);
-                       if (info->monspecs.modedb)
-                               fb_destroy_modedb(info->monspecs.modedb);
-                       if (info->screen_base)
-                               vfree(info->screen_base);
-
-                       fb_destroy_modelist(&info->modelist);
-
-                       framebuffer_release(info);
-               }
-
-               if (dev->backing_buffer)
-                       vfree(dev->backing_buffer);
-
-               kref_put(&dev->kref, dlfb_free); /* ref for framebuffer */
-               kref_put(&dev->kref, dlfb_free); /* last ref from kref_init */
-
-               /* dev has been deallocated. Do not dereference */
-       }
-
-       return retval;
-}
-
-static void dlfb_usb_disconnect(struct usb_interface *interface)
-{
-       struct dlfb_data *dev;
-       struct fb_info *info;
-       int i;
-
-       dev = usb_get_intfdata(interface);
-       info = dev->info;
-
-       dl_info("USB disconnect starting\n");
-
-       /* we virtualize until all fb clients release. Then we free */
-       dev->virtualized = true;
-
-       /* When non-active we'll update virtual framebuffer, but no new urbs */
-       atomic_set(&dev->usb_active, 0);
-
-       /* remove udlfb's sysfs interfaces */
-       for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
-               device_remove_file(info->dev, &fb_device_attrs[i]);
-       device_remove_bin_file(info->dev, &edid_attr);
-
-       usb_set_intfdata(interface, NULL);
-
-       /* if clients still have us open, will be freed on last close */
-       if (dev->fb_count == 0)
-               schedule_delayed_work(&dev->free_framebuffer_work, 0);
-
-       /* release reference taken by kref_init in probe() */
-       kref_put(&dev->kref, dlfb_free);
-
-       /* consider dlfb_data freed */
-
-       return;
-}
-
-static struct usb_driver dlfb_driver = {
-       .name = "udlfb",
-       .probe = dlfb_usb_probe,
-       .disconnect = dlfb_usb_disconnect,
-       .id_table = id_table,
-};
-
-static int __init dlfb_module_init(void)
-{
-       int res;
-
-       res = usb_register(&dlfb_driver);
-       if (res)
-               err("usb_register failed. Error number %d", res);
-
-       return res;
-}
-
-static void __exit dlfb_module_exit(void)
-{
-       usb_deregister(&dlfb_driver);
-}
-
-module_init(dlfb_module_init);
-module_exit(dlfb_module_exit);
-
-static void dlfb_urb_completion(struct urb *urb)
-{
-       struct urb_node *unode = urb->context;
-       struct dlfb_data *dev = unode->dev;
-       unsigned long flags;
-
-       /* sync/async unlink faults aren't errors */
-       if (urb->status) {
-               if (!(urb->status == -ENOENT ||
-                   urb->status == -ECONNRESET ||
-                   urb->status == -ESHUTDOWN)) {
-                       dl_err("%s - nonzero write bulk status received: %d\n",
-                               __func__, urb->status);
-                       atomic_set(&dev->lost_pixels, 1);
-               }
-       }
-
-       urb->transfer_buffer_length = dev->urbs.size; /* reset to actual */
-
-       spin_lock_irqsave(&dev->urbs.lock, flags);
-       list_add_tail(&unode->entry, &dev->urbs.list);
-       dev->urbs.available++;
-       spin_unlock_irqrestore(&dev->urbs.lock, flags);
-
-       /*
-        * When using fb_defio, we deadlock if up() is called
-        * while another is waiting. So queue to another process.
-        */
-       if (fb_defio)
-               schedule_delayed_work(&unode->release_urb_work, 0);
-       else
-               up(&dev->urbs.limit_sem);
-}
-
-static void dlfb_free_urb_list(struct dlfb_data *dev)
-{
-       int count = dev->urbs.count;
-       struct list_head *node;
-       struct urb_node *unode;
-       struct urb *urb;
-       int ret;
-       unsigned long flags;
-
-       dl_notice("Waiting for completes and freeing all render urbs\n");
-
-       /* keep waiting and freeing, until we've got 'em all */
-       while (count--) {
-
-               /* Getting interrupted means a leak, but ok at shutdown*/
-               ret = down_interruptible(&dev->urbs.limit_sem);
-               if (ret)
-                       break;
-
-               spin_lock_irqsave(&dev->urbs.lock, flags);
-
-               node = dev->urbs.list.next; /* have reserved one with sem */
-               list_del_init(node);
-
-               spin_unlock_irqrestore(&dev->urbs.lock, flags);
-
-               unode = list_entry(node, struct urb_node, entry);
-               urb = unode->urb;
-
-               /* Free each separately allocated piece */
-               usb_free_coherent(urb->dev, dev->urbs.size,
-                                 urb->transfer_buffer, urb->transfer_dma);
-               usb_free_urb(urb);
-               kfree(node);
-       }
-
-}
-
-static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size)
-{
-       int i = 0;
-       struct urb *urb;
-       struct urb_node *unode;
-       char *buf;
-
-       spin_lock_init(&dev->urbs.lock);
-
-       dev->urbs.size = size;
-       INIT_LIST_HEAD(&dev->urbs.list);
-
-       while (i < count) {
-               unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL);
-               if (!unode)
-                       break;
-               unode->dev = dev;
-
-               INIT_DELAYED_WORK(&unode->release_urb_work,
-                         dlfb_release_urb_work);
-
-               urb = usb_alloc_urb(0, GFP_KERNEL);
-               if (!urb) {
-                       kfree(unode);
-                       break;
-               }
-               unode->urb = urb;
-
-               buf = usb_alloc_coherent(dev->udev, MAX_TRANSFER, GFP_KERNEL,
-                                        &urb->transfer_dma);
-               if (!buf) {
-                       kfree(unode);
-                       usb_free_urb(urb);
-                       break;
-               }
-
-               /* urb->transfer_buffer_length set to actual before submit */
-               usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 1),
-                       buf, size, dlfb_urb_completion, unode);
-               urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
-
-               list_add_tail(&unode->entry, &dev->urbs.list);
-
-               i++;
-       }
-
-       sema_init(&dev->urbs.limit_sem, i);
-       dev->urbs.count = i;
-       dev->urbs.available = i;
-
-       dl_notice("allocated %d %d byte urbs\n", i, (int) size);
-
-       return i;
-}
-
-static struct urb *dlfb_get_urb(struct dlfb_data *dev)
-{
-       int ret = 0;
-       struct list_head *entry;
-       struct urb_node *unode;
-       struct urb *urb = NULL;
-       unsigned long flags;
-
-       /* Wait for an in-flight buffer to complete and get re-queued */
-       ret = down_timeout(&dev->urbs.limit_sem, GET_URB_TIMEOUT);
-       if (ret) {
-               atomic_set(&dev->lost_pixels, 1);
-               dl_warn("wait for urb interrupted: %x available: %d\n",
-                      ret, dev->urbs.available);
-               goto error;
-       }
-
-       spin_lock_irqsave(&dev->urbs.lock, flags);
-
-       BUG_ON(list_empty(&dev->urbs.list)); /* reserved one with limit_sem */
-       entry = dev->urbs.list.next;
-       list_del_init(entry);
-       dev->urbs.available--;
-
-       spin_unlock_irqrestore(&dev->urbs.lock, flags);
-
-       unode = list_entry(entry, struct urb_node, entry);
-       urb = unode->urb;
-
-error:
-       return urb;
-}
-
-static int dlfb_submit_urb(struct dlfb_data *dev, struct urb *urb, size_t len)
-{
-       int ret;
-
-       BUG_ON(len > dev->urbs.size);
-
-       urb->transfer_buffer_length = len; /* set to actual payload len */
-       ret = usb_submit_urb(urb, GFP_KERNEL);
-       if (ret) {
-               dlfb_urb_completion(urb); /* because no one else will */
-               atomic_set(&dev->lost_pixels, 1);
-               dl_err("usb_submit_urb error %x\n", ret);
-       }
-       return ret;
-}
-
-module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
-MODULE_PARM_DESC(console, "Allow fbcon to consume first framebuffer found");
-
-module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
-MODULE_PARM_DESC(fb_defio, "Enable fb_defio mmap support. *Experimental*");
-
-MODULE_AUTHOR("Roberto De Ioris <roberto@unbit.it>, "
-             "Jaya Kumar <jayakumar.lkml@gmail.com>, "
-             "Bernie Thompson <bernie@plugable.com>");
-MODULE_DESCRIPTION("DisplayLink kernel framebuffer driver");
-MODULE_LICENSE("GPL");
-