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authorPaul Mundt <lethal@linux-sh.org>2011-01-06 18:10:09 +0900
committerPaul Mundt <lethal@linux-sh.org>2011-01-06 18:10:09 +0900
commitca9c20ce2b383032b71bdae9ec0b468d428ca8d4 (patch)
tree3f2568b3f2c89b18369cbff0769f15d62f6ca5e5 /drivers/staging
parent17ca20cb7d04a259c9194879f77466bde606dda5 (diff)
parent81f6f3c1047392a22b9a20bbecf98c7f2d6f922a (diff)
Merge branch 'fbdev/udlfb'
Diffstat (limited to 'drivers/staging')
-rw-r--r--drivers/staging/Kconfig2
-rw-r--r--drivers/staging/Makefile1
-rw-r--r--drivers/staging/udlfb/Kconfig14
-rw-r--r--drivers/staging/udlfb/Makefile1
-rw-r--r--drivers/staging/udlfb/udlfb.c1916
-rw-r--r--drivers/staging/udlfb/udlfb.h117
-rw-r--r--drivers/staging/udlfb/udlfb.txt144
7 files changed, 0 insertions, 2195 deletions
diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index 5eafdf43555..df31a722807 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -111,8 +111,6 @@ source "drivers/staging/vt6655/Kconfig"
source "drivers/staging/vt6656/Kconfig"
-source "drivers/staging/udlfb/Kconfig"
-
source "drivers/staging/hv/Kconfig"
source "drivers/staging/vme/Kconfig"
diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
index a97a955c094..7a15c0c82b6 100644
--- a/drivers/staging/Makefile
+++ b/drivers/staging/Makefile
@@ -38,7 +38,6 @@ obj-$(CONFIG_USB_SERIAL_QUATECH_USB2) += quatech_usb2/
obj-$(CONFIG_OCTEON_ETHERNET) += octeon/
obj-$(CONFIG_VT6655) += vt6655/
obj-$(CONFIG_VT6656) += vt6656/
-obj-$(CONFIG_FB_UDL) += udlfb/
obj-$(CONFIG_HYPERV) += hv/
obj-$(CONFIG_VME_BUS) += vme/
obj-$(CONFIG_MRST_RAR_HANDLER) += memrar/
diff --git a/drivers/staging/udlfb/Kconfig b/drivers/staging/udlfb/Kconfig
deleted file mode 100644
index 65bd5db4ca5..00000000000
--- a/drivers/staging/udlfb/Kconfig
+++ /dev/null
@@ -1,14 +0,0 @@
-config FB_UDL
- tristate "Displaylink USB Framebuffer support"
- depends on FB && USB
- select FB_MODE_HELPERS
- select FB_SYS_FILLRECT
- select FB_SYS_COPYAREA
- select FB_SYS_IMAGEBLIT
- select FB_SYS_FOPS
- select FB_DEFERRED_IO
- ---help---
- This is a kernel framebuffer driver for DisplayLink USB devices.
- Supports fbdev clients like xf86-video-fbdev, kdrive, fbi, and
- mplayer -vo fbdev. Supports all USB 2.0 era DisplayLink devices.
- To compile as a module, choose M here: the module name is udlfb.
diff --git a/drivers/staging/udlfb/Makefile b/drivers/staging/udlfb/Makefile
deleted file mode 100644
index 30d9e675b10..00000000000
--- a/drivers/staging/udlfb/Makefile
+++ /dev/null
@@ -1 +0,0 @@
-obj-$(CONFIG_FB_UDL) += udlfb.o
diff --git a/drivers/staging/udlfb/udlfb.c b/drivers/staging/udlfb/udlfb.c
deleted file mode 100644
index b7ac1600526..00000000000
--- a/drivers/staging/udlfb/udlfb.c
+++ /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_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) {
- 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");
-
diff --git a/drivers/staging/udlfb/udlfb.h b/drivers/staging/udlfb/udlfb.h
deleted file mode 100644
index 6f9785e9d62..00000000000
--- a/drivers/staging/udlfb/udlfb.h
+++ /dev/null
@@ -1,117 +0,0 @@
-#ifndef UDLFB_H
-#define UDLFB_H
-
-/*
- * TODO: Propose standard fb.h ioctl for reporting damage,
- * using _IOWR() and one of the existing area structs from fb.h
- * Consider these ioctls deprecated, but they're still used by the
- * DisplayLink X server as yet - need both to be modified in tandem
- * when new ioctl(s) are ready.
- */
-#define DLFB_IOCTL_RETURN_EDID 0xAD
-#define DLFB_IOCTL_REPORT_DAMAGE 0xAA
-struct dloarea {
- int x, y;
- int w, h;
- int x2, y2;
-};
-
-struct urb_node {
- struct list_head entry;
- struct dlfb_data *dev;
- struct delayed_work release_urb_work;
- struct urb *urb;
-};
-
-struct urb_list {
- struct list_head list;
- spinlock_t lock;
- struct semaphore limit_sem;
- int available;
- int count;
- size_t size;
-};
-
-struct dlfb_data {
- struct usb_device *udev;
- struct device *gdev; /* &udev->dev */
- struct fb_info *info;
- struct urb_list urbs;
- struct kref kref;
- char *backing_buffer;
- int fb_count;
- bool virtualized; /* true when physical usb device not present */
- struct delayed_work free_framebuffer_work;
- atomic_t usb_active; /* 0 = update virtual buffer, but no usb traffic */
- atomic_t lost_pixels; /* 1 = a render op failed. Need screen refresh */
- char *edid; /* null until we read edid from hw or get from sysfs */
- size_t edid_size;
- int sku_pixel_limit;
- int base16;
- int base8;
- u32 pseudo_palette[256];
- /* blit-only rendering path metrics, exposed through sysfs */
- atomic_t bytes_rendered; /* raw pixel-bytes driver asked to render */
- atomic_t bytes_identical; /* saved effort with backbuffer comparison */
- atomic_t bytes_sent; /* to usb, after compression including overhead */
- atomic_t cpu_kcycles_used; /* transpired during pixel processing */
-};
-
-#define NR_USB_REQUEST_I2C_SUB_IO 0x02
-#define NR_USB_REQUEST_CHANNEL 0x12
-
-/* -BULK_SIZE as per usb-skeleton. Can we get full page and avoid overhead? */
-#define BULK_SIZE 512
-#define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE)
-#define WRITES_IN_FLIGHT (4)
-
-#define MIN_EDID_SIZE 128
-#define MAX_EDID_SIZE 128
-
-#define MAX_VENDOR_DESCRIPTOR_SIZE 256
-
-#define GET_URB_TIMEOUT HZ
-#define FREE_URB_TIMEOUT (HZ*2)
-
-#define BPP 2
-#define MAX_CMD_PIXELS 255
-
-#define RLX_HEADER_BYTES 7
-#define MIN_RLX_PIX_BYTES 4
-#define MIN_RLX_CMD_BYTES (RLX_HEADER_BYTES + MIN_RLX_PIX_BYTES)
-
-#define RLE_HEADER_BYTES 6
-#define MIN_RLE_PIX_BYTES 3
-#define MIN_RLE_CMD_BYTES (RLE_HEADER_BYTES + MIN_RLE_PIX_BYTES)
-
-#define RAW_HEADER_BYTES 6
-#define MIN_RAW_PIX_BYTES 2
-#define MIN_RAW_CMD_BYTES (RAW_HEADER_BYTES + MIN_RAW_PIX_BYTES)
-
-#define DL_DEFIO_WRITE_DELAY 5 /* fb_deferred_io.delay in jiffies */
-#define DL_DEFIO_WRITE_DISABLE (HZ*60) /* "disable" with long delay */
-
-/* remove these once align.h patch is taken into kernel */
-#define DL_ALIGN_UP(x, a) ALIGN(x, a)
-#define DL_ALIGN_DOWN(x, a) ALIGN(x-(a-1), a)
-
-/* remove once this gets added to sysfs.h */
-#define __ATTR_RW(attr) __ATTR(attr, 0644, attr##_show, attr##_store)
-
-/*
- * udlfb is both a usb device, and a framebuffer device.
- * They may exist at the same time, but during various stages
- * inactivity, teardown, or "virtual" operation, only one or the
- * other will exist (one will outlive the other). So we can't
- * call the dev_*() macros, because we don't have a stable dev object.
- */
-#define dl_err(format, arg...) \
- pr_err("udlfb: " format, ## arg)
-#define dl_warn(format, arg...) \
- pr_warning("udlfb: " format, ## arg)
-#define dl_notice(format, arg...) \
- pr_notice("udlfb: " format, ## arg)
-#define dl_info(format, arg...) \
- pr_info("udlfb: " format, ## arg)
-
-#endif
diff --git a/drivers/staging/udlfb/udlfb.txt b/drivers/staging/udlfb/udlfb.txt
deleted file mode 100644
index 7fdde2a02a2..00000000000
--- a/drivers/staging/udlfb/udlfb.txt
+++ /dev/null
@@ -1,144 +0,0 @@
-
-What is udlfb?
-===============
-
-This is a driver for DisplayLink USB 2.0 era graphics chips.
-
-DisplayLink chips provide simple hline/blit operations with some compression,
-pairing that with a hardware framebuffer (16MB) on the other end of the
-USB wire. That hardware framebuffer is able to drive the VGA, DVI, or HDMI
-monitor with no CPU involvement until a pixel has to change.
-
-The CPU or other local resource does all the rendering; optinally compares the
-result with a local shadow of the remote hardware framebuffer to identify
-the minimal set of pixels that have changed; and compresses and sends those
-pixels line-by-line via USB bulk transfers.
-
-Because of the efficiency of bulk transfers and a protocol on top that
-does not require any acks - the effect is very low latency that
-can support surprisingly high resolutions with good performance for
-non-gaming and non-video applications.
-
-Mode setting, EDID read, etc are other bulk or control transfers. Mode
-setting is very flexible - able to set nearly arbitrary modes from any timing.
-
-Advantages of USB graphics in general:
-
- * Ability to add a nearly arbitrary number of displays to any USB 2.0
- capable system. On Linux, number of displays is limited by fbdev interface
- (FB_MAX is currently 32). Of course, all USB devices on the same
- host controller share the same 480Mbs USB 2.0 interface.
-
-Advantages of supporting DisplayLink chips with kernel framebuffer interface:
-
- * The actual hardware functionality of DisplayLink chips matches nearly
- one-to-one with the fbdev interface, making the driver quite small and
- tight relative to the functionality it provides.
- * X servers and other applications can use the standard fbdev interface
- from user mode to talk to the device, without needing to know anything
- about USB or DisplayLink's protocol at all. A "displaylink" X driver
- and a slightly modified "fbdev" X driver are among those that already do.
-
-Disadvantages:
-
- * Fbdev's mmap interface assumes a real hardware framebuffer is mapped.
- In the case of USB graphics, it is just an allocated (virtual) buffer.
- Writes need to be detected and encoded into USB bulk transfers by the CPU.
- Accurate damage/changed area notifications work around this problem.
- In the future, hopefully fbdev will be enhanced with an small standard
- interface to allow mmap clients to report damage, for the benefit
- of virtual or remote framebuffers.
- * Fbdev does not arbitrate client ownership of the framebuffer well.
- * Fbcon assumes the first framebuffer it finds should be consumed for console.
- * It's not clear what the future of fbdev is, given the rise of KMS/DRM.
-
-How to use it?
-==============
-
-Udlfb, when loaded as a module, will match against all USB 2.0 generation
-DisplayLink chips (Alex and Ollie family). It will then attempt to read the EDID
-of the monitor, and set the best common mode between the DisplayLink device
-and the monitor's capabilities.
-
-If the DisplayLink device is successful, it will paint a "green screen" which
-means that from a hardware and fbdev software perspective, everything is good.
-
-At that point, a /dev/fb? interface will be present for user-mode applications
-to open and begin writing to the framebuffer of the DisplayLink device using
-standard fbdev calls. Note that if mmap() is used, by default the user mode
-application must send down damage notifcations to trigger repaints of the
-changed regions. Alternatively, udlfb can be recompiled with experimental
-defio support enabled, to support a page-fault based detection mechanism
-that can work without explicit notifcation.
-
-The most common client of udlfb is xf86-video-displaylink or a modified
-xf86-video-fbdev X server. These servers have no real DisplayLink specific
-code. They write to the standard framebuffer interface and rely on udlfb
-to do its thing. The one extra feature they have is the ability to report
-rectangles from the X DAMAGE protocol extension down to udlfb via udlfb's
-damage interface (which will hopefully be standardized for all virtual
-framebuffers that need damage info). These damage notifications allow
-udlfb to efficiently process the changed pixels.
-
-Module Options
-==============
-
-Special configuration for udlfb is usually unnecessary. There are a few
-options, however.
-
-From the command line, pass options to modprobe
-modprobe udlfb defio=1 console=1
-
-Or for permanent option, create file like /etc/modprobe.d/options with text
-options udlfb defio=1 console=1
-
-Accepted options:
-
-fb_defio Make use of the fb_defio (CONFIG_FB_DEFERRED_IO) kernel
- module to track changed areas of the framebuffer by page faults.
- Standard fbdev applications that use mmap but that do not
- report damage, may be able to work with this enabled.
- Disabled by default because of overhead and other issues.
-
-console Allow fbcon to attach to udlfb provided framebuffers. This
- is disabled by default because fbcon will aggressively consume
- the first framebuffer it finds, which isn't usually what the
- user wants in the case of USB displays.
-
-Sysfs Attributes
-================
-
-Udlfb creates several files in /sys/class/graphics/fb?
-Where ? is the sequential framebuffer id of the particular DisplayLink device
-
-edid If a valid EDID blob is written to this file (typically
- by a udev rule), then udlfb will use this EDID as a
- backup in case reading the actual EDID of the monitor
- attached to the DisplayLink device fails. This is
- especially useful for fixed panels, etc. that cannot
- communicate their capabilities via EDID. Reading
- this file returns the current EDID of the attached
- monitor (or last backup value written). This is
- useful to get the EDID of the attached monitor,
- which can be passed to utilities like parse-edid.
-
-metrics_bytes_rendered 32-bit count of pixel bytes rendered
-
-metrics_bytes_identical 32-bit count of how many of those bytes were found to be
- unchanged, based on a shadow framebuffer check
-
-metrics_bytes_sent 32-bit count of how many bytes were transferred over
- USB to communicate the resulting changed pixels to the
- hardware. Includes compression and protocol overhead
-
-metrics_cpu_kcycles_used 32-bit count of CPU cycles used in processing the
- above pixels (in thousands of cycles).
-
-metrics_reset Write-only. Any write to this file resets all metrics
- above to zero. Note that the 32-bit counters above
- roll over very quickly. To get reliable results, design
- performance tests to start and finish in a very short
- period of time (one minute or less is safe).
-
---
-Bernie Thompson <bernie@plugable.com>