Merge branch 'staging-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
Linus Torvalds [Tue, 11 Jan 2011 00:04:53 +0000 (16:04 -0800)]
* 'staging-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6: (510 commits)
  staging: speakup: fix failure handling
  staging: usbip: remove double giveback of URB
  Staging: batman-adv: Remove batman-adv from staging
  Staging: hv: Use only one txf buffer per channel and kmalloc/GFP_KERNEL on initialize
  staging: hv: remove unneeded osd_schedule_callback
  staging: hv: convert channel_mgmt.c to not call osd_schedule_callback
  staging: hv: convert vmbus_on_msg_dpc to not call osd_schedule_callback
  staging: brcm80211: Fix WL_<type> logging macros
  Staging: IIO: DDS: AD9833 / AD9834 driver
  Staging: IIO: dds.h convenience macros
  Staging: IIO: Direct digital synthesis abi documentation
  staging: brcm80211: Convert ETHER_TYPE_802_1X to ETH_P_PAE
  staging: brcm80211: Remove unused ETHER_TYPE_<foo> #defines
  staging: brcm80211: Remove ETHER_HDR_LEN, use ETH_HLEN
  staging: brcm80211: Convert ETHER_ADDR_LEN to ETH_ALEN
  staging: brcm80211: Convert ETHER_IS<FOO> to is_<foo>_ether_addr
  staging: brcm80211: Remove unused ether_<foo> #defines and struct
  staging: brcm80211: Convert ETHER_IS_MULTI to is_multicast_ether_addr
  staging: brcm80211: Remove unused #defines ETHER_<foo>_LOCALADDR
  Staging: comedi: Fix checkpatch.pl issues in file s526.c
  ...

Fix up trivial conflict in drivers/video/udlfb.c

1  2 
MAINTAINERS
drivers/staging/Kconfig
drivers/staging/Makefile
drivers/staging/bcm/InterfaceInit.c
drivers/staging/cx25821/cx25821-alsa.c
drivers/staging/zram/zram_drv.c
drivers/usb/serial/option.c
drivers/video/udlfb.c

diff --cc MAINTAINERS
Simple merge
Simple merge
Simple merge
@@@ -239,67 -203,51 +203,51 @@@ usbbcm_device_probe(struct usb_interfac
        psIntfAdapter->interface = intf;
        usb_set_intfdata(intf, psIntfAdapter);
  
-       BCM_DEBUG_PRINT(psAdapter,DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL, "psIntfAdapter 0x%p",psIntfAdapter);
+       BCM_DEBUG_PRINT(psAdapter, DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL,
+               "psIntfAdapter 0x%p\n", psIntfAdapter);
        retval = InterfaceAdapterInit(psIntfAdapter);
-       if(retval)
-       {
+       if (retval) {
                /* If the Firmware/Cfg File is not present
-                * then return success, let the application
-                * download the files.
-                */
-               if(-ENOENT == retval){
-                       BCM_DEBUG_PRINT(psAdapter,DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL, "File Not Found, Use App to Download\n");
+                * then return success, let the application
+                * download the files.
+                */
+               if (-ENOENT == retval) {
+                       BCM_DEBUG_PRINT(psAdapter, DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL,
+                               "File Not Found.  Use app to download.\n");
                        return STATUS_SUCCESS;
                }
-               BCM_DEBUG_PRINT(psAdapter,DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL, "InterfaceAdapterInit Failed \n");
+               BCM_DEBUG_PRINT(psAdapter, DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL,
+                       "InterfaceAdapterInit failed.\n");
                usb_set_intfdata(intf, NULL);
-               udev = interface_to_usbdev (intf);
+               udev = interface_to_usbdev(intf);
                usb_put_dev(udev);
-               if(psAdapter->bUsbClassDriverRegistered == TRUE)
-                               usb_deregister_dev (intf, &usbbcm_class);
                InterfaceAdapterFree(psIntfAdapter);
-               return retval ;
+               return retval;
        }
-       if(psAdapter->chip_id > T3)
-       {
-               uint32_t uiNackZeroLengthInt=4;
-               if(wrmalt(psAdapter, DISABLE_USB_ZERO_LEN_INT, &uiNackZeroLengthInt, sizeof(uiNackZeroLengthInt)))
-               {
-                       return -EIO;;
-               }
+       if (psAdapter->chip_id > T3) {
+               uint32_t uiNackZeroLengthInt = 4;
+               retval = wrmalt(psAdapter, DISABLE_USB_ZERO_LEN_INT, &uiNackZeroLengthInt, sizeof(uiNackZeroLengthInt));
+               if (retval)
+                       return retval;
        }
  
-       udev = interface_to_usbdev (intf);
        /* Check whether the USB-Device Supports remote Wake-Up */
-       if(USB_CONFIG_ATT_WAKEUP & udev->actconfig->desc.bmAttributes)
-       {
+       if (USB_CONFIG_ATT_WAKEUP & udev->actconfig->desc.bmAttributes) {
                /* If Suspend then only support dynamic suspend */
-               if(psAdapter->bDoSuspend)
-               {
+               if (psAdapter->bDoSuspend) {
  #ifdef CONFIG_PM
 -                      udev->autosuspend_delay = 0;
 +                      pm_runtime_set_autosuspend_delay(&udev->dev, 0);
                        intf->needs_remote_wakeup = 1;
- #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 35)
-                       udev->autosuspend_disabled = 0;
- #else
                        usb_enable_autosuspend(udev);
- #endif
-                       device_init_wakeup(&intf->dev,1);
- #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 32)
-                       usb_autopm_disable(intf);
- #endif
+                       device_init_wakeup(&intf->dev, 1);
                        INIT_WORK(&psIntfAdapter->usbSuspendWork, putUsbSuspend);
-                       BCM_DEBUG_PRINT(psAdapter,DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL, "Enabling USB Auto-Suspend\n");
+                       BCM_DEBUG_PRINT(psAdapter, DBG_TYPE_INITEXIT, DRV_ENTRY, DBG_LVL_ALL,
+                               "Enabling USB Auto-Suspend\n");
  #endif
-               }
-               else
-               {
+               } else {
                        intf->needs_remote_wakeup = 0;
- #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 35)
-                       udev->autosuspend_disabled = 1;
- #else
                        usb_disable_autosuspend(udev);
- #endif
                }
        }
  
Simple merge
Simple merge
index 020589a,0000000..2c8364e
mode 100644,000000..100644
--- /dev/null
@@@ -1,1879 -1,0 +1,1878 @@@
 +/*
 + * 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.
 + */
 +
 +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 +
 +#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 <video/udlfb.h>
 +#include "edid.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 |
 +              FBINFO_VIRTFB |
 +              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;
 +
 +      pr_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;
 +}
 +
 +/*
 + * 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;
 +      struct dlfb_data *dev = info->par;
 +      u32 offset = (u32) *ppos;
 +
 +      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);
 +      }
 +
 +      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;
 +
 +      sys_copyarea(info, area);
 +
 +      dlfb_handle_damage(dev, area->dx, area->dy,
 +                      area->width, area->height, info->screen_base);
 +}
 +
 +static void dlfb_ops_imageblit(struct fb_info *info,
 +                              const struct fb_image *image)
 +{
 +      struct dlfb_data *dev = info->par;
 +
 +      sys_imageblit(info, image);
 +
 +      dlfb_handle_damage(dev, image->dx, image->dy,
 +                      image->width, image->height, info->screen_base);
 +}
 +
 +static void dlfb_ops_fillrect(struct fb_info *info,
 +                        const struct fb_fillrect *rect)
 +{
 +      struct dlfb_data *dev = info->par;
 +
 +      sys_fillrect(info, rect);
 +
 +      dlfb_handle_damage(dev, rect->dx, rect->dy, rect->width,
 +                            rect->height, info->screen_base);
 +}
 +
 +/*
 + * 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);
 +}
 +
 +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) {
 +                      pr_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);
 +
 +      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);
 +      }
 +
 +      pr_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);
 +
 +      pr_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);
 +
 +      pr_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);
 +
 +      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;
 +      }
 +
 +      pr_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) {
 +              pr_warn("%dx%d beyond chip capabilities\n",
 +                     mode->xres, mode->yres);
 +              return 0;
 +      }
 +
 +      pr_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;
 +
 +      pr_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 = fb_sys_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;
 +
 +      pr_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) {
 +                      pr_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);
++              new_back = vzalloc(new_len);
 +              if (!new_back)
-                       pr_info("No shadow/backing buffer allcoated\n");
++                      pr_info("No shadow/backing buffer allocated\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(EDID_LENGTH, 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, EDID_LENGTH);
 +
 +              if (i >= EDID_LENGTH)
 +                      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) {
 +
 +              pr_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)
 +                              pr_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 >= EDID_LENGTH) {
 +                      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;
 +                              pr_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;
 +
 +      pr_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 != EDID_LENGTH) || (src_off != 0))
 +              return 0;
 +
 +      dlfb_setup_modes(dev, fb_info, src, src_size);
 +
 +      if (dev->edid && (memcmp(src, dev->edid, src_size) == 0)) {
 +              pr_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 = EDID_LENGTH,
 +      .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_IWUSR, 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) {
 +              pr_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));
 +                              pr_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 */
 +      pr_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);
 +
 +      pr_info("%s %s - serial #%s\n",
 +              usbdev->manufacturer, usbdev->product, usbdev->serial);
 +      pr_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);
 +      pr_info("console enable=%d\n", console);
 +      pr_info("fb_defio enable=%d\n", fb_defio);
 +
 +      dev->sku_pixel_limit = 2048 * 1152; /* default to maximum */
 +
 +      if (!dlfb_parse_vendor_descriptor(dev, usbdev)) {
 +              pr_err("firmware not recognized. Assume incompatible device\n");
 +              goto error;
 +      }
 +
 +      if (!dlfb_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
 +              retval = -ENOMEM;
 +              pr_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;
 +              pr_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) {
 +              pr_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) {
 +              pr_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) {
 +              pr_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);
 +
 +      pr_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;
 +
 +      pr_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)) {
 +                      pr_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;
 +
 +      pr_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;
 +
 +      pr_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);
 +              pr_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);
 +              pr_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");
 +