From 96f8d864afd646e4a52ea55462b7d83e3b94fd5c Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Tue, 16 Nov 2010 14:00:24 +0900 Subject: fbdev: move udlfb out of staging. udlfb has undergone a fair bit of cleanup recently and is effectively at the point where it can be liberated from staging purgatory and promoted to a real driver. The outstanding cleanups are all minor, with some of them dependent on drivers/video headers, so these will be done incrementally from udlfb's new home. Requested-by: Bernie Thompson Signed-off-by: Paul Mundt diff --git a/Documentation/fb/udlfb.txt b/Documentation/fb/udlfb.txt new file mode 100644 index 0000000..7fdde2a --- /dev/null +++ b/Documentation/fb/udlfb.txt @@ -0,0 +1,144 @@ + +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 diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig index 5eafdf4..df31a72 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 a97a955..7a15c0c 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 65bd5db..0000000 --- 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 30d9e67..0000000 --- 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 fed2510..0000000 --- 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 - * Copyright (C) 2009 Jaya Kumar - * Copyright (C) 2009 Bernie Thompson - * - * 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 -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "udlfb.h" - -static struct fb_fix_screeninfo dlfb_fix = { - .id = "udlfb", - .type = FB_TYPE_PACKED_PIXELS, - .visual = FB_VISUAL_TRUECOLOR, - .xpanstep = 0, - .ypanstep = 0, - .ywrapstep = 0, - .accel = FB_ACCEL_NONE, -}; - -static const u32 udlfb_info_flags = FBINFO_DEFAULT | FBINFO_READS_FAST | -#ifdef FBINFO_VIRTFB - FBINFO_VIRTFB | -#endif - FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT | - FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR; - -/* - * There are many DisplayLink-based products, all with unique PIDs. We are able - * to support all volume ones (circa 2009) with a single driver, so we match - * globally on VID. TODO: Probe() needs to detect when we might be running - * "future" chips, and bail on those, so a compatible driver can match. - */ -static struct usb_device_id id_table[] = { - {.idVendor = 0x17e9, .match_flags = USB_DEVICE_ID_MATCH_VENDOR,}, - {}, -}; -MODULE_DEVICE_TABLE(usb, id_table); - -/* module options */ -static int console; /* Optionally allow fbcon to consume first framebuffer */ -static int fb_defio; /* Optionally enable experimental fb_defio mmap support */ - -/* dlfb keeps a list of urbs for efficient bulk transfers */ -static void dlfb_urb_completion(struct urb *urb); -static struct urb *dlfb_get_urb(struct dlfb_data *dev); -static int dlfb_submit_urb(struct dlfb_data *dev, struct urb * urb, size_t len); -static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size); -static void dlfb_free_urb_list(struct dlfb_data *dev); - -/* - * All DisplayLink bulk operations start with 0xAF, followed by specific code - * All operations are written to buffers which then later get sent to device - */ -static char *dlfb_set_register(char *buf, u8 reg, u8 val) -{ - *buf++ = 0xAF; - *buf++ = 0x20; - *buf++ = reg; - *buf++ = val; - return buf; -} - -static char *dlfb_vidreg_lock(char *buf) -{ - return dlfb_set_register(buf, 0xFF, 0x00); -} - -static char *dlfb_vidreg_unlock(char *buf) -{ - return dlfb_set_register(buf, 0xFF, 0xFF); -} - -/* - * On/Off for driving the DisplayLink framebuffer to the display - * 0x00 H and V sync on - * 0x01 H and V sync off (screen blank but powered) - * 0x07 DPMS powerdown (requires modeset to come back) - */ -static char *dlfb_enable_hvsync(char *buf, bool enable) -{ - if (enable) - return dlfb_set_register(buf, 0x1F, 0x00); - else - return dlfb_set_register(buf, 0x1F, 0x07); -} - -static char *dlfb_set_color_depth(char *buf, u8 selection) -{ - return dlfb_set_register(buf, 0x00, selection); -} - -static char *dlfb_set_base16bpp(char *wrptr, u32 base) -{ - /* the base pointer is 16 bits wide, 0x20 is hi byte. */ - wrptr = dlfb_set_register(wrptr, 0x20, base >> 16); - wrptr = dlfb_set_register(wrptr, 0x21, base >> 8); - return dlfb_set_register(wrptr, 0x22, base); -} - -/* - * DisplayLink HW has separate 16bpp and 8bpp framebuffers. - * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer - */ -static char *dlfb_set_base8bpp(char *wrptr, u32 base) -{ - wrptr = dlfb_set_register(wrptr, 0x26, base >> 16); - wrptr = dlfb_set_register(wrptr, 0x27, base >> 8); - return dlfb_set_register(wrptr, 0x28, base); -} - -static char *dlfb_set_register_16(char *wrptr, u8 reg, u16 value) -{ - wrptr = dlfb_set_register(wrptr, reg, value >> 8); - return dlfb_set_register(wrptr, reg+1, value); -} - -/* - * This is kind of weird because the controller takes some - * register values in a different byte order than other registers. - */ -static char *dlfb_set_register_16be(char *wrptr, u8 reg, u16 value) -{ - wrptr = dlfb_set_register(wrptr, reg, value); - return dlfb_set_register(wrptr, reg+1, value >> 8); -} - -/* - * LFSR is linear feedback shift register. The reason we have this is - * because the display controller needs to minimize the clock depth of - * various counters used in the display path. So this code reverses the - * provided value into the lfsr16 value by counting backwards to get - * the value that needs to be set in the hardware comparator to get the - * same actual count. This makes sense once you read above a couple of - * times and think about it from a hardware perspective. - */ -static u16 dlfb_lfsr16(u16 actual_count) -{ - u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */ - - while (actual_count--) { - lv = ((lv << 1) | - (((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1)) - & 0xFFFF; - } - - return (u16) lv; -} - -/* - * This does LFSR conversion on the value that is to be written. - * See LFSR explanation above for more detail. - */ -static char *dlfb_set_register_lfsr16(char *wrptr, u8 reg, u16 value) -{ - return dlfb_set_register_16(wrptr, reg, dlfb_lfsr16(value)); -} - -/* - * This takes a standard fbdev screeninfo struct and all of its monitor mode - * details and converts them into the DisplayLink equivalent register commands. - */ -static char *dlfb_set_vid_cmds(char *wrptr, struct fb_var_screeninfo *var) -{ - u16 xds, yds; - u16 xde, yde; - u16 yec; - - /* x display start */ - xds = var->left_margin + var->hsync_len; - wrptr = dlfb_set_register_lfsr16(wrptr, 0x01, xds); - /* x display end */ - xde = xds + var->xres; - wrptr = dlfb_set_register_lfsr16(wrptr, 0x03, xde); - - /* y display start */ - yds = var->upper_margin + var->vsync_len; - wrptr = dlfb_set_register_lfsr16(wrptr, 0x05, yds); - /* y display end */ - yde = yds + var->yres; - wrptr = dlfb_set_register_lfsr16(wrptr, 0x07, yde); - - /* x end count is active + blanking - 1 */ - wrptr = dlfb_set_register_lfsr16(wrptr, 0x09, - xde + var->right_margin - 1); - - /* libdlo hardcodes hsync start to 1 */ - wrptr = dlfb_set_register_lfsr16(wrptr, 0x0B, 1); - - /* hsync end is width of sync pulse + 1 */ - wrptr = dlfb_set_register_lfsr16(wrptr, 0x0D, var->hsync_len + 1); - - /* hpixels is active pixels */ - wrptr = dlfb_set_register_16(wrptr, 0x0F, var->xres); - - /* yendcount is vertical active + vertical blanking */ - yec = var->yres + var->upper_margin + var->lower_margin + - var->vsync_len; - wrptr = dlfb_set_register_lfsr16(wrptr, 0x11, yec); - - /* libdlo hardcodes vsync start to 0 */ - wrptr = dlfb_set_register_lfsr16(wrptr, 0x13, 0); - - /* vsync end is width of vsync pulse */ - wrptr = dlfb_set_register_lfsr16(wrptr, 0x15, var->vsync_len); - - /* vpixels is active pixels */ - wrptr = dlfb_set_register_16(wrptr, 0x17, var->yres); - - /* convert picoseconds to 5kHz multiple for pclk5k = x * 1E12/5k */ - wrptr = dlfb_set_register_16be(wrptr, 0x1B, - 200*1000*1000/var->pixclock); - - return wrptr; -} - -/* - * This takes a standard fbdev screeninfo struct that was fetched or prepared - * and then generates the appropriate command sequence that then drives the - * display controller. - */ -static int dlfb_set_video_mode(struct dlfb_data *dev, - struct fb_var_screeninfo *var) -{ - char *buf; - char *wrptr; - int retval = 0; - int writesize; - struct urb *urb; - - if (!atomic_read(&dev->usb_active)) - return -EPERM; - - urb = dlfb_get_urb(dev); - if (!urb) - return -ENOMEM; - - buf = (char *) urb->transfer_buffer; - - /* - * This first section has to do with setting the base address on the - * controller * associated with the display. There are 2 base - * pointers, currently, we only * use the 16 bpp segment. - */ - wrptr = dlfb_vidreg_lock(buf); - wrptr = dlfb_set_color_depth(wrptr, 0x00); - /* set base for 16bpp segment to 0 */ - wrptr = dlfb_set_base16bpp(wrptr, 0); - /* set base for 8bpp segment to end of fb */ - wrptr = dlfb_set_base8bpp(wrptr, dev->info->fix.smem_len); - - wrptr = dlfb_set_vid_cmds(wrptr, var); - wrptr = dlfb_enable_hvsync(wrptr, true); - wrptr = dlfb_vidreg_unlock(wrptr); - - writesize = wrptr - buf; - - retval = dlfb_submit_urb(dev, urb, writesize); - - return retval; -} - -static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma) -{ - unsigned long start = vma->vm_start; - unsigned long size = vma->vm_end - vma->vm_start; - unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; - unsigned long page, pos; - - if (offset + size > info->fix.smem_len) - return -EINVAL; - - pos = (unsigned long)info->fix.smem_start + offset; - - dl_notice("mmap() framebuffer addr:%lu size:%lu\n", - pos, size); - - while (size > 0) { - page = vmalloc_to_pfn((void *)pos); - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) - return -EAGAIN; - - start += PAGE_SIZE; - pos += PAGE_SIZE; - if (size > PAGE_SIZE) - size -= PAGE_SIZE; - else - size = 0; - } - - vma->vm_flags |= VM_RESERVED; /* avoid to swap out this VMA */ - return 0; -} - -/* - * Trims identical data from front and back of line - * Sets new front buffer address and width - * And returns byte count of identical pixels - * Assumes CPU natural alignment (unsigned long) - * for back and front buffer ptrs and width - */ -static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes) -{ - int j, k; - const unsigned long *back = (const unsigned long *) bback; - const unsigned long *front = (const unsigned long *) *bfront; - const int width = *width_bytes / sizeof(unsigned long); - int identical = width; - int start = width; - int end = width; - - prefetch((void *) front); - prefetch((void *) back); - - for (j = 0; j < width; j++) { - if (back[j] != front[j]) { - start = j; - break; - } - } - - for (k = width - 1; k > j; k--) { - if (back[k] != front[k]) { - end = k+1; - break; - } - } - - identical = start + (width - end); - *bfront = (u8 *) &front[start]; - *width_bytes = (end - start) * sizeof(unsigned long); - - return identical * sizeof(unsigned long); -} - -/* - * Render a command stream for an encoded horizontal line segment of pixels. - * - * A command buffer holds several commands. - * It always begins with a fresh command header - * (the protocol doesn't require this, but we enforce it to allow - * multiple buffers to be potentially encoded and sent in parallel). - * A single command encodes one contiguous horizontal line of pixels - * - * The function relies on the client to do all allocation, so that - * rendering can be done directly to output buffers (e.g. USB URBs). - * The function fills the supplied command buffer, providing information - * on where it left off, so the client may call in again with additional - * buffers if the line will take several buffers to complete. - * - * A single command can transmit a maximum of 256 pixels, - * regardless of the compression ratio (protocol design limit). - * To the hardware, 0 for a size byte means 256 - * - * Rather than 256 pixel commands which are either rl or raw encoded, - * the rlx command simply assumes alternating raw and rl spans within one cmd. - * This has a slightly larger header overhead, but produces more even results. - * It also processes all data (read and write) in a single pass. - * Performance benchmarks of common cases show it having just slightly better - * compression than 256 pixel raw or rle commands, with similar CPU consumpion. - * But for very rl friendly data, will compress not quite as well. - */ -static void dlfb_compress_hline( - const uint16_t **pixel_start_ptr, - const uint16_t *const pixel_end, - uint32_t *device_address_ptr, - uint8_t **command_buffer_ptr, - const uint8_t *const cmd_buffer_end) -{ - const uint16_t *pixel = *pixel_start_ptr; - uint32_t dev_addr = *device_address_ptr; - uint8_t *cmd = *command_buffer_ptr; - const int bpp = 2; - - while ((pixel_end > pixel) && - (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) { - uint8_t *raw_pixels_count_byte = 0; - uint8_t *cmd_pixels_count_byte = 0; - const uint16_t *raw_pixel_start = 0; - const uint16_t *cmd_pixel_start, *cmd_pixel_end = 0; - - prefetchw((void *) cmd); /* pull in one cache line at least */ - - *cmd++ = 0xAF; - *cmd++ = 0x6B; - *cmd++ = (uint8_t) ((dev_addr >> 16) & 0xFF); - *cmd++ = (uint8_t) ((dev_addr >> 8) & 0xFF); - *cmd++ = (uint8_t) ((dev_addr) & 0xFF); - - cmd_pixels_count_byte = cmd++; /* we'll know this later */ - cmd_pixel_start = pixel; - - raw_pixels_count_byte = cmd++; /* we'll know this later */ - raw_pixel_start = pixel; - - cmd_pixel_end = pixel + min(MAX_CMD_PIXELS + 1, - min((int)(pixel_end - pixel), - (int)(cmd_buffer_end - cmd) / bpp)); - - prefetch_range((void *) pixel, (cmd_pixel_end - pixel) * bpp); - - while (pixel < cmd_pixel_end) { - const uint16_t * const repeating_pixel = pixel; - - *(uint16_t *)cmd = cpu_to_be16p(pixel); - cmd += 2; - pixel++; - - if (unlikely((pixel < cmd_pixel_end) && - (*pixel == *repeating_pixel))) { - /* go back and fill in raw pixel count */ - *raw_pixels_count_byte = ((repeating_pixel - - raw_pixel_start) + 1) & 0xFF; - - while ((pixel < cmd_pixel_end) - && (*pixel == *repeating_pixel)) { - pixel++; - } - - /* immediately after raw data is repeat byte */ - *cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF; - - /* Then start another raw pixel span */ - raw_pixel_start = pixel; - raw_pixels_count_byte = cmd++; - } - } - - if (pixel > raw_pixel_start) { - /* finalize last RAW span */ - *raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF; - } - - *cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF; - dev_addr += (pixel - cmd_pixel_start) * bpp; - } - - if (cmd_buffer_end <= MIN_RLX_CMD_BYTES + cmd) { - /* Fill leftover bytes with no-ops */ - if (cmd_buffer_end > cmd) - memset(cmd, 0xAF, cmd_buffer_end - cmd); - cmd = (uint8_t *) cmd_buffer_end; - } - - *command_buffer_ptr = cmd; - *pixel_start_ptr = pixel; - *device_address_ptr = dev_addr; - - return; -} - -/* - * There are 3 copies of every pixel: The front buffer that the fbdev - * client renders to, the actual framebuffer across the USB bus in hardware - * (that we can only write to, slowly, and can never read), and (optionally) - * our shadow copy that tracks what's been sent to that hardware buffer. - */ -static int dlfb_render_hline(struct dlfb_data *dev, struct urb **urb_ptr, - const char *front, char **urb_buf_ptr, - u32 byte_offset, u32 byte_width, - int *ident_ptr, int *sent_ptr) -{ - const u8 *line_start, *line_end, *next_pixel; - u32 dev_addr = dev->base16 + byte_offset; - struct urb *urb = *urb_ptr; - u8 *cmd = *urb_buf_ptr; - u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length; - - line_start = (u8 *) (front + byte_offset); - next_pixel = line_start; - line_end = next_pixel + byte_width; - - if (dev->backing_buffer) { - int offset; - const u8 *back_start = (u8 *) (dev->backing_buffer - + byte_offset); - - *ident_ptr += dlfb_trim_hline(back_start, &next_pixel, - &byte_width); - - offset = next_pixel - line_start; - line_end = next_pixel + byte_width; - dev_addr += offset; - back_start += offset; - line_start += offset; - - memcpy((char *)back_start, (char *) line_start, - byte_width); - } - - while (next_pixel < line_end) { - - dlfb_compress_hline((const uint16_t **) &next_pixel, - (const uint16_t *) line_end, &dev_addr, - (u8 **) &cmd, (u8 *) cmd_end); - - if (cmd >= cmd_end) { - int len = cmd - (u8 *) urb->transfer_buffer; - if (dlfb_submit_urb(dev, urb, len)) - return 1; /* lost pixels is set */ - *sent_ptr += len; - urb = dlfb_get_urb(dev); - if (!urb) - return 1; /* lost_pixels is set */ - *urb_ptr = urb; - cmd = urb->transfer_buffer; - cmd_end = &cmd[urb->transfer_buffer_length]; - } - } - - *urb_buf_ptr = cmd; - - return 0; -} - -int dlfb_handle_damage(struct dlfb_data *dev, int x, int y, - int width, int height, char *data) -{ - int i, ret; - char *cmd; - cycles_t start_cycles, end_cycles; - int bytes_sent = 0; - int bytes_identical = 0; - struct urb *urb; - int aligned_x; - - start_cycles = get_cycles(); - - aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long)); - width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long)); - x = aligned_x; - - if ((width <= 0) || - (x + width > dev->info->var.xres) || - (y + height > dev->info->var.yres)) - return -EINVAL; - - if (!atomic_read(&dev->usb_active)) - return 0; - - urb = dlfb_get_urb(dev); - if (!urb) - return 0; - cmd = urb->transfer_buffer; - - for (i = y; i < y + height ; i++) { - const int line_offset = dev->info->fix.line_length * i; - const int byte_offset = line_offset + (x * BPP); - - if (dlfb_render_hline(dev, &urb, - (char *) dev->info->fix.smem_start, - &cmd, byte_offset, width * BPP, - &bytes_identical, &bytes_sent)) - goto error; - } - - if (cmd > (char *) urb->transfer_buffer) { - /* Send partial buffer remaining before exiting */ - int len = cmd - (char *) urb->transfer_buffer; - ret = dlfb_submit_urb(dev, urb, len); - bytes_sent += len; - } else - dlfb_urb_completion(urb); - -error: - atomic_add(bytes_sent, &dev->bytes_sent); - atomic_add(bytes_identical, &dev->bytes_identical); - atomic_add(width*height*2, &dev->bytes_rendered); - end_cycles = get_cycles(); - atomic_add(((unsigned int) ((end_cycles - start_cycles) - >> 10)), /* Kcycles */ - &dev->cpu_kcycles_used); - - return 0; -} - -static ssize_t dlfb_ops_read(struct fb_info *info, char __user *buf, - size_t count, loff_t *ppos) -{ - ssize_t result = -ENOSYS; - -#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE - result = fb_sys_read(info, buf, count, ppos); -#endif - - return result; -} - -/* - * Path triggered by usermode clients who write to filesystem - * e.g. cat filename > /dev/fb1 - * Not used by X Windows or text-mode console. But useful for testing. - * Slow because of extra copy and we must assume all pixels dirty. - */ -static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf, - size_t count, loff_t *ppos) -{ - ssize_t result = -ENOSYS; - struct dlfb_data *dev = info->par; - u32 offset = (u32) *ppos; - -#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE - - result = fb_sys_write(info, buf, count, ppos); - - if (result > 0) { - int start = max((int)(offset / info->fix.line_length) - 1, 0); - int lines = min((u32)((result / info->fix.line_length) + 1), - (u32)info->var.yres); - - dlfb_handle_damage(dev, 0, start, info->var.xres, - lines, info->screen_base); - } -#endif - - return result; -} - -/* hardware has native COPY command (see libdlo), but not worth it for fbcon */ -static void dlfb_ops_copyarea(struct fb_info *info, - const struct fb_copyarea *area) -{ - - struct dlfb_data *dev = info->par; - -#if defined CONFIG_FB_SYS_COPYAREA || defined CONFIG_FB_SYS_COPYAREA_MODULE - - sys_copyarea(info, area); - - dlfb_handle_damage(dev, area->dx, area->dy, - area->width, area->height, info->screen_base); -#endif - -} - -static void dlfb_ops_imageblit(struct fb_info *info, - const struct fb_image *image) -{ - struct dlfb_data *dev = info->par; - -#if defined CONFIG_FB_SYS_IMAGEBLIT || defined CONFIG_FB_SYS_IMAGEBLIT_MODULE - - sys_imageblit(info, image); - - dlfb_handle_damage(dev, image->dx, image->dy, - image->width, image->height, info->screen_base); - -#endif - -} - -static void dlfb_ops_fillrect(struct fb_info *info, - const struct fb_fillrect *rect) -{ - struct dlfb_data *dev = info->par; - -#if defined CONFIG_FB_SYS_FILLRECT || defined CONFIG_FB_SYS_FILLRECT_MODULE - - sys_fillrect(info, rect); - - dlfb_handle_damage(dev, rect->dx, rect->dy, rect->width, - rect->height, info->screen_base); -#endif - -} - -#ifdef CONFIG_FB_DEFERRED_IO -/* - * NOTE: fb_defio.c is holding info->fbdefio.mutex - * Touching ANY framebuffer memory that triggers a page fault - * in fb_defio will cause a deadlock, when it also tries to - * grab the same mutex. - */ -static void dlfb_dpy_deferred_io(struct fb_info *info, - struct list_head *pagelist) -{ - struct page *cur; - struct fb_deferred_io *fbdefio = info->fbdefio; - struct dlfb_data *dev = info->par; - struct urb *urb; - char *cmd; - cycles_t start_cycles, end_cycles; - int bytes_sent = 0; - int bytes_identical = 0; - int bytes_rendered = 0; - - if (!fb_defio) - return; - - if (!atomic_read(&dev->usb_active)) - return; - - start_cycles = get_cycles(); - - urb = dlfb_get_urb(dev); - if (!urb) - return; - - cmd = urb->transfer_buffer; - - /* walk the written page list and render each to device */ - list_for_each_entry(cur, &fbdefio->pagelist, lru) { - - if (dlfb_render_hline(dev, &urb, (char *) info->fix.smem_start, - &cmd, cur->index << PAGE_SHIFT, - PAGE_SIZE, &bytes_identical, &bytes_sent)) - goto error; - bytes_rendered += PAGE_SIZE; - } - - if (cmd > (char *) urb->transfer_buffer) { - /* Send partial buffer remaining before exiting */ - int len = cmd - (char *) urb->transfer_buffer; - dlfb_submit_urb(dev, urb, len); - bytes_sent += len; - } else - dlfb_urb_completion(urb); - -error: - atomic_add(bytes_sent, &dev->bytes_sent); - atomic_add(bytes_identical, &dev->bytes_identical); - atomic_add(bytes_rendered, &dev->bytes_rendered); - end_cycles = get_cycles(); - atomic_add(((unsigned int) ((end_cycles - start_cycles) - >> 10)), /* Kcycles */ - &dev->cpu_kcycles_used); -} - -#endif - -static int dlfb_get_edid(struct dlfb_data *dev, char *edid, int len) -{ - int i; - int ret; - char *rbuf; - - rbuf = kmalloc(2, GFP_KERNEL); - if (!rbuf) - return 0; - - for (i = 0; i < len; i++) { - ret = usb_control_msg(dev->udev, - usb_rcvctrlpipe(dev->udev, 0), (0x02), - (0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2, - HZ); - if (ret < 1) { - dl_err("Read EDID byte %d failed err %x\n", i, ret); - i--; - break; - } - edid[i] = rbuf[1]; - } - - kfree(rbuf); - - return i; -} - -static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd, - unsigned long arg) -{ - - struct dlfb_data *dev = info->par; - struct dloarea *area = NULL; - - if (!atomic_read(&dev->usb_active)) - return 0; - - /* TODO: Update X server to get this from sysfs instead */ - if (cmd == DLFB_IOCTL_RETURN_EDID) { - char *edid = (char *)arg; - if (copy_to_user(edid, dev->edid, dev->edid_size)) - return -EFAULT; - return 0; - } - - /* TODO: Help propose a standard fb.h ioctl to report mmap damage */ - if (cmd == DLFB_IOCTL_REPORT_DAMAGE) { - - /* - * If we have a damage-aware client, turn fb_defio "off" - * To avoid perf imact of unecessary page fault handling. - * Done by resetting the delay for this fb_info to a very - * long period. Pages will become writable and stay that way. - * Reset to normal value when all clients have closed this fb. - */ - if (info->fbdefio) - info->fbdefio->delay = DL_DEFIO_WRITE_DISABLE; - - area = (struct dloarea *)arg; - - if (area->x < 0) - area->x = 0; - - if (area->x > info->var.xres) - area->x = info->var.xres; - - if (area->y < 0) - area->y = 0; - - if (area->y > info->var.yres) - area->y = info->var.yres; - - dlfb_handle_damage(dev, area->x, area->y, area->w, area->h, - info->screen_base); - } - - return 0; -} - -/* taken from vesafb */ -static int -dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green, - unsigned blue, unsigned transp, struct fb_info *info) -{ - int err = 0; - - if (regno >= info->cmap.len) - return 1; - - if (regno < 16) { - if (info->var.red.offset == 10) { - /* 1:5:5:5 */ - ((u32 *) (info->pseudo_palette))[regno] = - ((red & 0xf800) >> 1) | - ((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11); - } else { - /* 0:5:6:5 */ - ((u32 *) (info->pseudo_palette))[regno] = - ((red & 0xf800)) | - ((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11); - } - } - - return err; -} - -/* - * It's common for several clients to have framebuffer open simultaneously. - * e.g. both fbcon and X. Makes things interesting. - * Assumes caller is holding info->lock (for open and release at least) - */ -static int dlfb_ops_open(struct fb_info *info, int user) -{ - struct dlfb_data *dev = info->par; - - /* - * fbcon aggressively connects to first framebuffer it finds, - * preventing other clients (X) from working properly. Usually - * not what the user wants. Fail by default with option to enable. - */ - if ((user == 0) & (!console)) - return -EBUSY; - - /* If the USB device is gone, we don't accept new opens */ - if (dev->virtualized) - return -ENODEV; - - dev->fb_count++; - - kref_get(&dev->kref); - -#ifdef CONFIG_FB_DEFERRED_IO - if (fb_defio && (info->fbdefio == NULL)) { - /* enable defio at last moment if not disabled by client */ - - struct fb_deferred_io *fbdefio; - - fbdefio = kmalloc(sizeof(struct fb_deferred_io), GFP_KERNEL); - - if (fbdefio) { - fbdefio->delay = DL_DEFIO_WRITE_DELAY; - fbdefio->deferred_io = dlfb_dpy_deferred_io; - } - - info->fbdefio = fbdefio; - fb_deferred_io_init(info); - } -#endif - - dl_notice("open /dev/fb%d user=%d fb_info=%p count=%d\n", - info->node, user, info, dev->fb_count); - - return 0; -} - -/* - * Called when all client interfaces to start transactions have been disabled, - * and all references to our device instance (dlfb_data) are released. - * Every transaction must have a reference, so we know are fully spun down - */ -static void dlfb_free(struct kref *kref) -{ - struct dlfb_data *dev = container_of(kref, struct dlfb_data, kref); - - /* this function will wait for all in-flight urbs to complete */ - if (dev->urbs.count > 0) - dlfb_free_urb_list(dev); - - if (dev->backing_buffer) - vfree(dev->backing_buffer); - - kfree(dev->edid); - - dl_warn("freeing dlfb_data %p\n", dev); - - kfree(dev); -} - -static void dlfb_release_urb_work(struct work_struct *work) -{ - struct urb_node *unode = container_of(work, struct urb_node, - release_urb_work.work); - - up(&unode->dev->urbs.limit_sem); -} - -static void dlfb_free_framebuffer_work(struct work_struct *work) -{ - struct dlfb_data *dev = container_of(work, struct dlfb_data, - free_framebuffer_work.work); - struct fb_info *info = dev->info; - int node = info->node; - - unregister_framebuffer(info); - - if (info->cmap.len != 0) - fb_dealloc_cmap(&info->cmap); - if (info->monspecs.modedb) - fb_destroy_modedb(info->monspecs.modedb); - if (info->screen_base) - vfree(info->screen_base); - - fb_destroy_modelist(&info->modelist); - - dev->info = 0; - - /* Assume info structure is freed after this point */ - framebuffer_release(info); - - dl_warn("fb_info for /dev/fb%d has been freed\n", node); - - /* ref taken in probe() as part of registering framebfufer */ - kref_put(&dev->kref, dlfb_free); -} - -/* - * Assumes caller is holding info->lock mutex (for open and release at least) - */ -static int dlfb_ops_release(struct fb_info *info, int user) -{ - struct dlfb_data *dev = info->par; - - dev->fb_count--; - - /* We can't free fb_info here - fbmem will touch it when we return */ - if (dev->virtualized && (dev->fb_count == 0)) - schedule_delayed_work(&dev->free_framebuffer_work, HZ); - -#ifdef CONFIG_FB_DEFERRED_IO - if ((dev->fb_count == 0) && (info->fbdefio)) { - fb_deferred_io_cleanup(info); - kfree(info->fbdefio); - info->fbdefio = NULL; - info->fbops->fb_mmap = dlfb_ops_mmap; - } -#endif - - dl_warn("released /dev/fb%d user=%d count=%d\n", - info->node, user, dev->fb_count); - - kref_put(&dev->kref, dlfb_free); - - return 0; -} - -/* - * Check whether a video mode is supported by the DisplayLink chip - * We start from monitor's modes, so don't need to filter that here - */ -static int dlfb_is_valid_mode(struct fb_videomode *mode, - struct fb_info *info) -{ - struct dlfb_data *dev = info->par; - - if (mode->xres * mode->yres > dev->sku_pixel_limit) { - dl_warn("%dx%d beyond chip capabilities\n", - mode->xres, mode->yres); - return 0; - } - - dl_info("%dx%d valid mode\n", mode->xres, mode->yres); - - return 1; -} - -static void dlfb_var_color_format(struct fb_var_screeninfo *var) -{ - const struct fb_bitfield red = { 11, 5, 0 }; - const struct fb_bitfield green = { 5, 6, 0 }; - const struct fb_bitfield blue = { 0, 5, 0 }; - - var->bits_per_pixel = 16; - var->red = red; - var->green = green; - var->blue = blue; -} - -static int dlfb_ops_check_var(struct fb_var_screeninfo *var, - struct fb_info *info) -{ - struct fb_videomode mode; - - /* TODO: support dynamically changing framebuffer size */ - if ((var->xres * var->yres * 2) > info->fix.smem_len) - return -EINVAL; - - /* set device-specific elements of var unrelated to mode */ - dlfb_var_color_format(var); - - fb_var_to_videomode(&mode, var); - - if (!dlfb_is_valid_mode(&mode, info)) - return -EINVAL; - - return 0; -} - -static int dlfb_ops_set_par(struct fb_info *info) -{ - struct dlfb_data *dev = info->par; - int result; - u16 *pix_framebuffer; - int i; - - dl_notice("set_par mode %dx%d\n", info->var.xres, info->var.yres); - - result = dlfb_set_video_mode(dev, &info->var); - - if ((result == 0) && (dev->fb_count == 0)) { - - /* paint greenscreen */ - - pix_framebuffer = (u16 *) info->screen_base; - for (i = 0; i < info->fix.smem_len / 2; i++) - pix_framebuffer[i] = 0x37e6; - - dlfb_handle_damage(dev, 0, 0, info->var.xres, info->var.yres, - info->screen_base); - } - - return result; -} - -/* - * In order to come back from full DPMS off, we need to set the mode again - */ -static int dlfb_ops_blank(int blank_mode, struct fb_info *info) -{ - struct dlfb_data *dev = info->par; - - if (blank_mode != FB_BLANK_UNBLANK) { - char *bufptr; - struct urb *urb; - - urb = dlfb_get_urb(dev); - if (!urb) - return 0; - - bufptr = (char *) urb->transfer_buffer; - bufptr = dlfb_vidreg_lock(bufptr); - bufptr = dlfb_enable_hvsync(bufptr, false); - bufptr = dlfb_vidreg_unlock(bufptr); - - dlfb_submit_urb(dev, urb, bufptr - - (char *) urb->transfer_buffer); - } else { - dlfb_set_video_mode(dev, &info->var); - } - - return 0; -} - -static struct fb_ops dlfb_ops = { - .owner = THIS_MODULE, - .fb_read = dlfb_ops_read, - .fb_write = dlfb_ops_write, - .fb_setcolreg = dlfb_ops_setcolreg, - .fb_fillrect = dlfb_ops_fillrect, - .fb_copyarea = dlfb_ops_copyarea, - .fb_imageblit = dlfb_ops_imageblit, - .fb_mmap = dlfb_ops_mmap, - .fb_ioctl = dlfb_ops_ioctl, - .fb_open = dlfb_ops_open, - .fb_release = dlfb_ops_release, - .fb_blank = dlfb_ops_blank, - .fb_check_var = dlfb_ops_check_var, - .fb_set_par = dlfb_ops_set_par, -}; - - -/* - * Assumes &info->lock held by caller - * Assumes no active clients have framebuffer open - */ -static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info) -{ - int retval = -ENOMEM; - int old_len = info->fix.smem_len; - int new_len; - unsigned char *old_fb = info->screen_base; - unsigned char *new_fb; - unsigned char *new_back; - - dl_warn("Reallocating framebuffer. Addresses will change!\n"); - - new_len = info->fix.line_length * info->var.yres; - - if (PAGE_ALIGN(new_len) > old_len) { - /* - * Alloc system memory for virtual framebuffer - */ - new_fb = vmalloc(new_len); - if (!new_fb) { - dl_err("Virtual framebuffer alloc failed\n"); - goto error; - } - - if (info->screen_base) { - memcpy(new_fb, old_fb, old_len); - vfree(info->screen_base); - } - - info->screen_base = new_fb; - info->fix.smem_len = PAGE_ALIGN(new_len); - info->fix.smem_start = (unsigned long) new_fb; - info->flags = udlfb_info_flags; - - /* - * Second framebuffer copy to mirror the framebuffer state - * on the physical USB device. We can function without this. - * But with imperfect damage info we may send pixels over USB - * that were, in fact, unchanged - wasting limited USB bandwidth - */ - new_back = vmalloc(new_len); - if (!new_back) - dl_info("No shadow/backing buffer allcoated\n"); - else { - if (dev->backing_buffer) - vfree(dev->backing_buffer); - dev->backing_buffer = new_back; - memset(dev->backing_buffer, 0, new_len); - } - } - - retval = 0; - -error: - return retval; -} - -/* - * 1) Get EDID from hw, or use sw default - * 2) Parse into various fb_info structs - * 3) Allocate virtual framebuffer memory to back highest res mode - * - * Parses EDID into three places used by various parts of fbdev: - * fb_var_screeninfo contains the timing of the monitor's preferred mode - * fb_info.monspecs is full parsed EDID info, including monspecs.modedb - * fb_info.modelist is a linked list of all monitor & VESA modes which work - * - * If EDID is not readable/valid, then modelist is all VESA modes, - * monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode - * Returns 0 if successful - */ -static int dlfb_setup_modes(struct dlfb_data *dev, - struct fb_info *info, - char *default_edid, size_t default_edid_size) -{ - int i; - const struct fb_videomode *default_vmode = NULL; - int result = 0; - char *edid; - int tries = 3; - - if (info->dev) /* only use mutex if info has been registered */ - mutex_lock(&info->lock); - - edid = kmalloc(MAX_EDID_SIZE, GFP_KERNEL); - if (!edid) { - result = -ENOMEM; - goto error; - } - - fb_destroy_modelist(&info->modelist); - memset(&info->monspecs, 0, sizeof(info->monspecs)); - - /* - * Try to (re)read EDID from hardware first - * EDID data may return, but not parse as valid - * Try again a few times, in case of e.g. analog cable noise - */ - while (tries--) { - - i = dlfb_get_edid(dev, edid, MAX_EDID_SIZE); - - if (i >= MIN_EDID_SIZE) - fb_edid_to_monspecs(edid, &info->monspecs); - - if (info->monspecs.modedb_len > 0) { - dev->edid = edid; - dev->edid_size = i; - break; - } - } - - /* If that fails, use a previously returned EDID if available */ - if (info->monspecs.modedb_len == 0) { - - dl_err("Unable to get valid EDID from device/display\n"); - - if (dev->edid) { - fb_edid_to_monspecs(dev->edid, &info->monspecs); - if (info->monspecs.modedb_len > 0) - dl_err("Using previously queried EDID\n"); - } - } - - /* If that fails, use the default EDID we were handed */ - if (info->monspecs.modedb_len == 0) { - if (default_edid_size >= MIN_EDID_SIZE) { - fb_edid_to_monspecs(default_edid, &info->monspecs); - if (info->monspecs.modedb_len > 0) { - memcpy(edid, default_edid, default_edid_size); - dev->edid = edid; - dev->edid_size = default_edid_size; - dl_err("Using default/backup EDID\n"); - } - } - } - - /* If we've got modes, let's pick a best default mode */ - if (info->monspecs.modedb_len > 0) { - - for (i = 0; i < info->monspecs.modedb_len; i++) { - if (dlfb_is_valid_mode(&info->monspecs.modedb[i], info)) - fb_add_videomode(&info->monspecs.modedb[i], - &info->modelist); - else /* if we've removed top/best mode */ - info->monspecs.misc &= ~FB_MISC_1ST_DETAIL; - } - - default_vmode = fb_find_best_display(&info->monspecs, - &info->modelist); - } - - /* If everything else has failed, fall back to safe default mode */ - if (default_vmode == NULL) { - - struct fb_videomode fb_vmode = {0}; - - /* - * Add the standard VESA modes to our modelist - * Since we don't have EDID, there may be modes that - * overspec monitor and/or are incorrect aspect ratio, etc. - * But at least the user has a chance to choose - */ - for (i = 0; i < VESA_MODEDB_SIZE; i++) { - if (dlfb_is_valid_mode((struct fb_videomode *) - &vesa_modes[i], info)) - fb_add_videomode(&vesa_modes[i], - &info->modelist); - } - - /* - * default to resolution safe for projectors - * (since they are most common case without EDID) - */ - fb_vmode.xres = 800; - fb_vmode.yres = 600; - fb_vmode.refresh = 60; - default_vmode = fb_find_nearest_mode(&fb_vmode, - &info->modelist); - } - - /* If we have good mode and no active clients*/ - if ((default_vmode != NULL) && (dev->fb_count == 0)) { - - fb_videomode_to_var(&info->var, default_vmode); - dlfb_var_color_format(&info->var); - - /* - * with mode size info, we can now alloc our framebuffer. - */ - memcpy(&info->fix, &dlfb_fix, sizeof(dlfb_fix)); - info->fix.line_length = info->var.xres * - (info->var.bits_per_pixel / 8); - - result = dlfb_realloc_framebuffer(dev, info); - - } else - result = -EINVAL; - -error: - if (edid && (dev->edid != edid)) - kfree(edid); - - if (info->dev) - mutex_unlock(&info->lock); - - return result; -} - -static ssize_t metrics_bytes_rendered_show(struct device *fbdev, - struct device_attribute *a, char *buf) { - struct fb_info *fb_info = dev_get_drvdata(fbdev); - struct dlfb_data *dev = fb_info->par; - return snprintf(buf, PAGE_SIZE, "%u\n", - atomic_read(&dev->bytes_rendered)); -} - -static ssize_t metrics_bytes_identical_show(struct device *fbdev, - struct device_attribute *a, char *buf) { - struct fb_info *fb_info = dev_get_drvdata(fbdev); - struct dlfb_data *dev = fb_info->par; - return snprintf(buf, PAGE_SIZE, "%u\n", - atomic_read(&dev->bytes_identical)); -} - -static ssize_t metrics_bytes_sent_show(struct device *fbdev, - struct device_attribute *a, char *buf) { - struct fb_info *fb_info = dev_get_drvdata(fbdev); - struct dlfb_data *dev = fb_info->par; - return snprintf(buf, PAGE_SIZE, "%u\n", - atomic_read(&dev->bytes_sent)); -} - -static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev, - struct device_attribute *a, char *buf) { - struct fb_info *fb_info = dev_get_drvdata(fbdev); - struct dlfb_data *dev = fb_info->par; - return snprintf(buf, PAGE_SIZE, "%u\n", - atomic_read(&dev->cpu_kcycles_used)); -} - -static ssize_t edid_show( - struct file *filp, - struct kobject *kobj, struct bin_attribute *a, - char *buf, loff_t off, size_t count) { - struct device *fbdev = container_of(kobj, struct device, kobj); - struct fb_info *fb_info = dev_get_drvdata(fbdev); - struct dlfb_data *dev = fb_info->par; - - if (dev->edid == NULL) - return 0; - - if ((off >= dev->edid_size) || (count > dev->edid_size)) - return 0; - - if (off + count > dev->edid_size) - count = dev->edid_size - off; - - dl_info("sysfs edid copy %p to %p, %d bytes\n", - dev->edid, buf, (int) count); - - memcpy(buf, dev->edid, count); - - return count; -} - -static ssize_t edid_store( - struct file *filp, - struct kobject *kobj, struct bin_attribute *a, - char *src, loff_t src_off, size_t src_size) { - struct device *fbdev = container_of(kobj, struct device, kobj); - struct fb_info *fb_info = dev_get_drvdata(fbdev); - struct dlfb_data *dev = fb_info->par; - - /* We only support write of entire EDID at once, no offset*/ - if ((src_size < MIN_EDID_SIZE) || - (src_size > MAX_EDID_SIZE) || - (src_off != 0)) - return 0; - - dlfb_setup_modes(dev, fb_info, src, src_size); - - if (dev->edid && (memcmp(src, dev->edid, src_size) == 0)) { - dl_info("sysfs written EDID is new default\n"); - dlfb_ops_set_par(fb_info); - return src_size; - } else - return 0; -} - -static ssize_t metrics_reset_store(struct device *fbdev, - struct device_attribute *attr, - const char *buf, size_t count) -{ - struct fb_info *fb_info = dev_get_drvdata(fbdev); - struct dlfb_data *dev = fb_info->par; - - atomic_set(&dev->bytes_rendered, 0); - atomic_set(&dev->bytes_identical, 0); - atomic_set(&dev->bytes_sent, 0); - atomic_set(&dev->cpu_kcycles_used, 0); - - return count; -} - -static struct bin_attribute edid_attr = { - .attr.name = "edid", - .attr.mode = 0666, - .size = MAX_EDID_SIZE, - .read = edid_show, - .write = edid_store -}; - -static struct device_attribute fb_device_attrs[] = { - __ATTR_RO(metrics_bytes_rendered), - __ATTR_RO(metrics_bytes_identical), - __ATTR_RO(metrics_bytes_sent), - __ATTR_RO(metrics_cpu_kcycles_used), - __ATTR(metrics_reset, S_IWUGO, NULL, metrics_reset_store), -}; - -/* - * This is necessary before we can communicate with the display controller. - */ -static int dlfb_select_std_channel(struct dlfb_data *dev) -{ - int ret; - u8 set_def_chn[] = { 0x57, 0xCD, 0xDC, 0xA7, - 0x1C, 0x88, 0x5E, 0x15, - 0x60, 0xFE, 0xC6, 0x97, - 0x16, 0x3D, 0x47, 0xF2 }; - - ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), - NR_USB_REQUEST_CHANNEL, - (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0, - set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT); - return ret; -} - -static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev, - struct usb_device *usbdev) -{ - char *desc; - char *buf; - char *desc_end; - - u8 total_len = 0; - - buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL); - if (!buf) - return false; - desc = buf; - - total_len = usb_get_descriptor(usbdev, 0x5f, /* vendor specific */ - 0, desc, MAX_VENDOR_DESCRIPTOR_SIZE); - if (total_len > 5) { - dl_info("vendor descriptor length:%x data:%02x %02x %02x %02x" \ - "%02x %02x %02x %02x %02x %02x %02x\n", - total_len, desc[0], - desc[1], desc[2], desc[3], desc[4], desc[5], desc[6], - desc[7], desc[8], desc[9], desc[10]); - - if ((desc[0] != total_len) || /* descriptor length */ - (desc[1] != 0x5f) || /* vendor descriptor type */ - (desc[2] != 0x01) || /* version (2 bytes) */ - (desc[3] != 0x00) || - (desc[4] != total_len - 2)) /* length after type */ - goto unrecognized; - - desc_end = desc + total_len; - desc += 5; /* the fixed header we've already parsed */ - - while (desc < desc_end) { - u8 length; - u16 key; - - key = *((u16 *) desc); - desc += sizeof(u16); - length = *desc; - desc++; - - switch (key) { - case 0x0200: { /* max_area */ - u32 max_area; - max_area = le32_to_cpu(*((u32 *)desc)); - dl_warn("DL chip limited to %d pixel modes\n", - max_area); - dev->sku_pixel_limit = max_area; - break; - } - default: - break; - } - desc += length; - } - } - - goto success; - -unrecognized: - /* allow udlfb to load for now even if firmware unrecognized */ - dl_err("Unrecognized vendor firmware descriptor\n"); - -success: - kfree(buf); - return true; -} -static int dlfb_usb_probe(struct usb_interface *interface, - const struct usb_device_id *id) -{ - struct usb_device *usbdev; - struct dlfb_data *dev = 0; - struct fb_info *info = 0; - int retval = -ENOMEM; - int i; - - /* usb initialization */ - - usbdev = interface_to_usbdev(interface); - - dev = kzalloc(sizeof(*dev), GFP_KERNEL); - if (dev == NULL) { - err("dlfb_usb_probe: failed alloc of dev struct\n"); - goto error; - } - - /* we need to wait for both usb and fbdev to spin down on disconnect */ - kref_init(&dev->kref); /* matching kref_put in usb .disconnect fn */ - kref_get(&dev->kref); /* matching kref_put in free_framebuffer_work */ - - dev->udev = usbdev; - dev->gdev = &usbdev->dev; /* our generic struct device * */ - usb_set_intfdata(interface, dev); - - dl_info("%s %s - serial #%s\n", - usbdev->manufacturer, usbdev->product, usbdev->serial); - dl_info("vid_%04x&pid_%04x&rev_%04x driver's dlfb_data struct at %p\n", - usbdev->descriptor.idVendor, usbdev->descriptor.idProduct, - usbdev->descriptor.bcdDevice, dev); - dl_info("console enable=%d\n", console); - dl_info("fb_defio enable=%d\n", fb_defio); - - dev->sku_pixel_limit = 2048 * 1152; /* default to maximum */ - - if (!dlfb_parse_vendor_descriptor(dev, usbdev)) { - dl_err("firmware not recognized. Assume incompatible device\n"); - goto error; - } - - if (!dlfb_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) { - retval = -ENOMEM; - dl_err("dlfb_alloc_urb_list failed\n"); - goto error; - } - - /* We don't register a new USB class. Our client interface is fbdev */ - - /* allocates framebuffer driver structure, not framebuffer memory */ - info = framebuffer_alloc(0, &usbdev->dev); - if (!info) { - retval = -ENOMEM; - dl_err("framebuffer_alloc failed\n"); - goto error; - } - - dev->info = info; - info->par = dev; - info->pseudo_palette = dev->pseudo_palette; - info->fbops = &dlfb_ops; - - retval = fb_alloc_cmap(&info->cmap, 256, 0); - if (retval < 0) { - dl_err("fb_alloc_cmap failed %x\n", retval); - goto error; - } - - INIT_DELAYED_WORK(&dev->free_framebuffer_work, - dlfb_free_framebuffer_work); - - INIT_LIST_HEAD(&info->modelist); - - retval = dlfb_setup_modes(dev, info, NULL, 0); - if (retval != 0) { - dl_err("unable to find common mode for display and adapter\n"); - goto error; - } - - /* ready to begin using device */ - - atomic_set(&dev->usb_active, 1); - dlfb_select_std_channel(dev); - - dlfb_ops_check_var(&info->var, info); - dlfb_ops_set_par(info); - - retval = register_framebuffer(info); - if (retval < 0) { - dl_err("register_framebuffer failed %d\n", retval); - goto error; - } - - for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) - device_create_file(info->dev, &fb_device_attrs[i]); - - device_create_bin_file(info->dev, &edid_attr); - - dl_info("DisplayLink USB device /dev/fb%d attached. %dx%d resolution." - " Using %dK framebuffer memory\n", info->node, - info->var.xres, info->var.yres, - ((dev->backing_buffer) ? - info->fix.smem_len * 2 : info->fix.smem_len) >> 10); - return 0; - -error: - if (dev) { - - if (info) { - if (info->cmap.len != 0) - fb_dealloc_cmap(&info->cmap); - if (info->monspecs.modedb) - fb_destroy_modedb(info->monspecs.modedb); - if (info->screen_base) - vfree(info->screen_base); - - fb_destroy_modelist(&info->modelist); - - framebuffer_release(info); - } - - if (dev->backing_buffer) - vfree(dev->backing_buffer); - - kref_put(&dev->kref, dlfb_free); /* ref for framebuffer */ - kref_put(&dev->kref, dlfb_free); /* last ref from kref_init */ - - /* dev has been deallocated. Do not dereference */ - } - - return retval; -} - -static void dlfb_usb_disconnect(struct usb_interface *interface) -{ - struct dlfb_data *dev; - struct fb_info *info; - int i; - - dev = usb_get_intfdata(interface); - info = dev->info; - - dl_info("USB disconnect starting\n"); - - /* we virtualize until all fb clients release. Then we free */ - dev->virtualized = true; - - /* When non-active we'll update virtual framebuffer, but no new urbs */ - atomic_set(&dev->usb_active, 0); - - /* remove udlfb's sysfs interfaces */ - for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) - device_remove_file(info->dev, &fb_device_attrs[i]); - device_remove_bin_file(info->dev, &edid_attr); - - usb_set_intfdata(interface, NULL); - - /* if clients still have us open, will be freed on last close */ - if (dev->fb_count == 0) - schedule_delayed_work(&dev->free_framebuffer_work, 0); - - /* release reference taken by kref_init in probe() */ - kref_put(&dev->kref, dlfb_free); - - /* consider dlfb_data freed */ - - return; -} - -static struct usb_driver dlfb_driver = { - .name = "udlfb", - .probe = dlfb_usb_probe, - .disconnect = dlfb_usb_disconnect, - .id_table = id_table, -}; - -static int __init dlfb_module_init(void) -{ - int res; - - res = usb_register(&dlfb_driver); - if (res) - err("usb_register failed. Error number %d", res); - - return res; -} - -static void __exit dlfb_module_exit(void) -{ - usb_deregister(&dlfb_driver); -} - -module_init(dlfb_module_init); -module_exit(dlfb_module_exit); - -static void dlfb_urb_completion(struct urb *urb) -{ - struct urb_node *unode = urb->context; - struct dlfb_data *dev = unode->dev; - unsigned long flags; - - /* sync/async unlink faults aren't errors */ - if (urb->status) { - if (!(urb->status == -ENOENT || - urb->status == -ECONNRESET || - urb->status == -ESHUTDOWN)) { - dl_err("%s - nonzero write bulk status received: %d\n", - __func__, urb->status); - atomic_set(&dev->lost_pixels, 1); - } - } - - urb->transfer_buffer_length = dev->urbs.size; /* reset to actual */ - - spin_lock_irqsave(&dev->urbs.lock, flags); - list_add_tail(&unode->entry, &dev->urbs.list); - dev->urbs.available++; - spin_unlock_irqrestore(&dev->urbs.lock, flags); - - /* - * When using fb_defio, we deadlock if up() is called - * while another is waiting. So queue to another process. - */ - if (fb_defio) - schedule_delayed_work(&unode->release_urb_work, 0); - else - up(&dev->urbs.limit_sem); -} - -static void dlfb_free_urb_list(struct dlfb_data *dev) -{ - int count = dev->urbs.count; - struct list_head *node; - struct urb_node *unode; - struct urb *urb; - int ret; - unsigned long flags; - - dl_notice("Waiting for completes and freeing all render urbs\n"); - - /* keep waiting and freeing, until we've got 'em all */ - while (count--) { - - /* Getting interrupted means a leak, but ok at shutdown*/ - ret = down_interruptible(&dev->urbs.limit_sem); - if (ret) - break; - - spin_lock_irqsave(&dev->urbs.lock, flags); - - node = dev->urbs.list.next; /* have reserved one with sem */ - list_del_init(node); - - spin_unlock_irqrestore(&dev->urbs.lock, flags); - - unode = list_entry(node, struct urb_node, entry); - urb = unode->urb; - - /* Free each separately allocated piece */ - usb_free_coherent(urb->dev, dev->urbs.size, - urb->transfer_buffer, urb->transfer_dma); - usb_free_urb(urb); - kfree(node); - } - -} - -static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size) -{ - int i = 0; - struct urb *urb; - struct urb_node *unode; - char *buf; - - spin_lock_init(&dev->urbs.lock); - - dev->urbs.size = size; - INIT_LIST_HEAD(&dev->urbs.list); - - while (i < count) { - unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL); - if (!unode) - break; - unode->dev = dev; - - INIT_DELAYED_WORK(&unode->release_urb_work, - dlfb_release_urb_work); - - urb = usb_alloc_urb(0, GFP_KERNEL); - if (!urb) { - kfree(unode); - break; - } - unode->urb = urb; - - buf = usb_alloc_coherent(dev->udev, MAX_TRANSFER, GFP_KERNEL, - &urb->transfer_dma); - if (!buf) { - kfree(unode); - usb_free_urb(urb); - break; - } - - /* urb->transfer_buffer_length set to actual before submit */ - usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 1), - buf, size, dlfb_urb_completion, unode); - urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; - - list_add_tail(&unode->entry, &dev->urbs.list); - - i++; - } - - sema_init(&dev->urbs.limit_sem, i); - dev->urbs.count = i; - dev->urbs.available = i; - - dl_notice("allocated %d %d byte urbs\n", i, (int) size); - - return i; -} - -static struct urb *dlfb_get_urb(struct dlfb_data *dev) -{ - int ret = 0; - struct list_head *entry; - struct urb_node *unode; - struct urb *urb = NULL; - unsigned long flags; - - /* Wait for an in-flight buffer to complete and get re-queued */ - ret = down_timeout(&dev->urbs.limit_sem, GET_URB_TIMEOUT); - if (ret) { - atomic_set(&dev->lost_pixels, 1); - dl_warn("wait for urb interrupted: %x available: %d\n", - ret, dev->urbs.available); - goto error; - } - - spin_lock_irqsave(&dev->urbs.lock, flags); - - BUG_ON(list_empty(&dev->urbs.list)); /* reserved one with limit_sem */ - entry = dev->urbs.list.next; - list_del_init(entry); - dev->urbs.available--; - - spin_unlock_irqrestore(&dev->urbs.lock, flags); - - unode = list_entry(entry, struct urb_node, entry); - urb = unode->urb; - -error: - return urb; -} - -static int dlfb_submit_urb(struct dlfb_data *dev, struct urb *urb, size_t len) -{ - int ret; - - BUG_ON(len > dev->urbs.size); - - urb->transfer_buffer_length = len; /* set to actual payload len */ - ret = usb_submit_urb(urb, GFP_KERNEL); - if (ret) { - dlfb_urb_completion(urb); /* because no one else will */ - atomic_set(&dev->lost_pixels, 1); - dl_err("usb_submit_urb error %x\n", ret); - } - return ret; -} - -module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); -MODULE_PARM_DESC(console, "Allow fbcon to consume first framebuffer found"); - -module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); -MODULE_PARM_DESC(fb_defio, "Enable fb_defio mmap support. *Experimental*"); - -MODULE_AUTHOR("Roberto De Ioris , " - "Jaya Kumar , " - "Bernie Thompson "); -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 6f9785e..0000000 --- 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 7fdde2a..0000000 --- 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 diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index 27c1fb4..37771d0 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -2034,6 +2034,20 @@ config FB_SM501 If unsure, say N. +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. config FB_PNX4008_DUM tristate "Display Update Module support on Philips PNX4008 board" diff --git a/drivers/video/Makefile b/drivers/video/Makefile index 485e8ed..03678e3 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -122,6 +122,7 @@ obj-$(CONFIG_FB_PNX4008_DUM_RGB) += pnx4008/ obj-$(CONFIG_FB_IBM_GXT4500) += gxt4500.o obj-$(CONFIG_FB_PS3) += ps3fb.o obj-$(CONFIG_FB_SM501) += sm501fb.o +obj-$(CONFIG_FB_UDL) += udlfb.o obj-$(CONFIG_FB_XILINX) += xilinxfb.o obj-$(CONFIG_SH_MIPI_DSI) += sh_mipi_dsi.o obj-$(CONFIG_FB_SH_MOBILE_HDMI) += sh_mobile_hdmi.o diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c new file mode 100644 index 0000000..0cca487 --- /dev/null +++ b/drivers/video/udlfb.c @@ -0,0 +1,1915 @@ +/* + * udlfb.c -- Framebuffer driver for DisplayLink USB controller + * + * Copyright (C) 2009 Roberto De Ioris + * Copyright (C) 2009 Jaya Kumar + * Copyright (C) 2009 Bernie Thompson + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include