/*
* udlfb.c -- Framebuffer driver for DisplayLink USB controller
*
* Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
* Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
* Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
*
* This file is subject to the terms and conditions of the GNU General Public
* License v2. See the file COPYING in the main directory of this archive for
* more details.
*
* Layout is based on skeletonfb by James Simmons and Geert Uytterhoeven,
* usb-skeleton by GregKH.
*
* Device-specific portions based on information from Displaylink, with work
* from Florian Echtler, Henrik Bjerregaard Pedersen, and others.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/usb.h>
#include <linux/uaccess.h>
#include <linux/mm.h>
#include <linux/fb.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/prefetch.h>
#include <linux/delay.h>
#include <video/udlfb.h>
#include "edid.h"
static struct fb_fix_screeninfo dlfb_fix = {
.id = "udlfb",
.type = FB_TYPE_PACKED_PIXELS,
.visual = FB_VISUAL_TRUECOLOR,
.xpanstep = 0,
.ypanstep = 0,
.ywrapstep = 0,
.accel = FB_ACCEL_NONE,
};
static const u32 udlfb_info_flags = FBINFO_DEFAULT | FBINFO_READS_FAST |
FBINFO_VIRTFB |
FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT |
FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR;
/*
* There are many DisplayLink-based graphics products, all with unique PIDs.
* So we match on DisplayLink's VID + Vendor-Defined Interface Class (0xff)
* We also require a match on SubClass (0x00) and Protocol (0x00),
* which is compatible with all known USB 2.0 era graphics chips and firmware,
* but allows DisplayLink to increment those for any future incompatible chips
*/
static struct usb_device_id id_table[] = {
{.idVendor = 0x17e9,
.bInterfaceClass = 0xff,
.bInterfaceSubClass = 0x00,
.bInterfaceProtocol = 0x00,
.match_flags = USB_DEVICE_ID_MATCH_VENDOR |
USB_DEVICE_ID_MATCH_INT_CLASS |
USB_DEVICE_ID_MATCH_INT_SUBCLASS |
USB_DEVICE_ID_MATCH_INT_PROTOCOL,
},
{},
};
MODULE_DEVICE_TABLE(usb, id_table);
/* module options */
static bool console = 1; /* Allow fbcon to open framebuffer */
static bool fb_defio = 1; /* Detect mmap writes using page faults */
static bool shadow = 1; /* Optionally disable shadow framebuffer */
/* 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);
}
/*
* Map FB_BLANK_* to DisplayLink register
* DLReg FB_BLANK_*
* ----- -----------------------------
* 0x00 FB_BLANK_UNBLANK (0)
* 0x01 FB_BLANK (1)
* 0x03 FB_BLANK_VSYNC_SUSPEND (2)
* 0x05 FB_BLANK_HSYNC_SUSPEND (3)
* 0x07 FB_BLANK_POWERDOWN (4) Note: requires modeset to come back
*/
static char *dlfb_blanking(char *buf, int fb_blank)
{
u8 reg;
switch (fb_blank) {
case FB_BLANK_POWERDOWN:
reg = 0x07;
break;
case FB_BLANK_HSYNC_SUSPEND:
reg = 0x05;
break;
case FB_BLANK_VSYNC_SUSPEND:
reg = 0x03;
break;
case FB_BLANK_NORMAL:
reg = 0x01;
break;
default:
reg = 0x00;
}
buf = dlfb_set_register(buf, 0x1F, reg);
return buf;
}
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_blanking(wrptr, FB_BLANK_UNBLANK);
wrptr = dlfb_vidreg_unlock(wrptr);
writesize = wrptr - buf;
retval = dlfb_submit_urb(dev, urb, writesize);
dev->blank_mode = FB_BLANK_UNBLANK;
return retval;
}
static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
unsigned long start = vma->vm_start;
unsigned long size = vma->vm_end - vma->vm_start;
unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
unsigned long page, pos;
if (offset + size > info->fix.smem_len)
return -EINVAL;
pos = (unsigned long)info->fix.smem_start + offset;
pr_notice("mmap() framebuffer addr:%lu size:%lu\n",
pos, size);
while (size > 0) {
page = vmalloc_to_pfn((void *)pos);
if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))
return -EAGAIN;
start += PAGE_SIZE;
pos += PAGE_SIZE;
if (size > PAGE_SIZE)
size -= PAGE_SIZE;
else
size = 0;
}
vma->vm_flags |= VM_RESERVED; /* avoid to swap out this VMA */
return 0;
}
/*
* Trims identical data from front and back of line
* Sets new front buffer address and width
* And returns byte count of identical pixels
* Assumes CPU natural alignment (unsigned long)
* for back and front buffer ptrs and width
*/
static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)
{
int j, k;
const unsigned long *back = (const unsigned long *) bback;
const unsigned long *front = (const unsigned long *) *bfront;
const int width = *width_bytes / sizeof(unsigned long);
int identical = width;
int start = width;
int end = width;
prefetch((void *) front);
prefetch((void *) back);
for (j = 0; j < width; j++) {
if (back[j] != front[j]) {
start = j;
break;
}
}
for (k = width - 1; k > j; k--) {
if (back[k] != front[k]) {
end = k+1;
break;
}
}
identical = start + (width - end);
*bfront = (u8 *) &front[start];
*width_bytes = (end - start) * sizeof(unsigned long);
return identical * sizeof(unsigned long);
}
/*
* Render a command stream for an encoded horizontal line segment of pixels.
*
* A command buffer holds several commands.
* It always begins with a fresh command header
* (the protocol doesn't require this, but we enforce it to allow
* multiple buffers to be potentially encoded and sent in parallel).
* A single command encodes one contiguous horizontal line of pixels
*
* The function relies on the client to do all allocation, so that
* rendering can be done directly to output buffers (e.g. USB URBs).
* The function fills the supplied command buffer, providing information
* on where it left off, so the client may call in again with additional
* buffers if the line will take several buffers to complete.
*
* A single command can transmit a maximum of 256 pixels,
* regardless of the compression ratio (protocol design limit).
* To the hardware, 0 for a size byte means 256
*
* Rather than 256 pixel commands which are either rl or raw encoded,
* the rlx command simply assumes alternating raw and rl spans within one cmd.
* This has a slightly larger header overhead, but produces more even results.
* It also processes all data (read and write) in a single pass.
* Performance benchmarks of common cases show it having just slightly better
* compression than 256 pixel raw or rle commands, with similar CPU consumpion.
* But for very rl friendly data, will compress not quite as well.
*/
static void dlfb_compress_hline(
const uint16_t **pixel_start_ptr,
const uint16_t *const pixel_end,
uint32_t *device_address_ptr,
uint8_t **command_buffer_ptr,
const uint8_t *const cmd_buffer_end)
{
const uint16_t *pixel = *pixel_start_ptr;
uint32_t dev_addr = *device_address_ptr;
uint8_t *cmd = *command_buffer_ptr;
const int bpp = 2;
while ((pixel_end > pixel) &&
(cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) {
uint8_t *raw_pixels_count_byte = 0;
uint8_t *cmd_pixels_count_byte = 0;
const uint16_t *raw_pixel_start = 0;
const uint16_t *cmd_pixel_start, *cmd_pixel_end = 0;
prefetchw((void *) cmd); /* pull in one cache line at least */
*cmd++ = 0xAF;
*cmd++ = 0x6B;
*cmd++ = (uint8_t) ((dev_addr >> 16) & 0xFF);
*cmd++ = (uint8_t) ((dev_addr >> 8) & 0xFF);
*cmd++ = (uint8_t) ((dev_addr) & 0xFF);
cmd_pixels_count_byte = cmd++; /* we'll know this later */
cmd_pixel_start = pixel;
raw_pixels_count_byte = cmd++; /* we'll know this later */
raw_pixel_start = pixel;
cmd_pixel_end = pixel + min(MAX_CMD_PIXELS + 1,
min((int)(pixel_end - pixel),
(int)(cmd_buffer_end - cmd) / bpp));
prefetch_range((void *) pixel, (cmd_pixel_end - pixel) * bpp);
while (pixel < cmd_pixel_end) {
const uint16_t * const repeating_pixel = pixel;
*(uint16_t *)cmd = cpu_to_be16p(pixel);
cmd += 2;
pixel++;
if (unlikely((pixel < cmd_pixel_end) &&
(*pixel == *repeating_pixel))) {
/* go back and fill in raw pixel count */
*raw_pixels_count_byte = ((repeating_pixel -
raw_pixel_start) + 1) & 0xFF;
while ((pixel < cmd_pixel_end)
&& (*pixel == *repeating_pixel)) {
pixel++;
}
/* immediately after raw data is repeat byte */
*cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF;
/* Then start another raw pixel span */
raw_pixel_start = pixel;
raw_pixels_count_byte = cmd++;
}
}
if (pixel > raw_pixel_start) {
/* finalize last RAW span */
*raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF;
}
*cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF;
dev_addr += (pixel - cmd_pixel_start) * bpp;
}
if (cmd_buffer_end <= MIN_RLX_CMD_BYTES + cmd) {
/* Fill leftover bytes with no-ops */
if (cmd_buffer_end > cmd)
memset(cmd, 0xAF, cmd_buffer_end - cmd);
cmd = (uint8_t *) cmd_buffer_end;
}
*command_buffer_ptr = cmd;
*pixel_start_ptr = pixel;
*device_address_ptr = dev_addr;
return;
}
/*
* There are 3 copies of every pixel: The front buffer that the fbdev
* client renders to, the actual framebuffer across the USB bus in hardware
* (that we can only write to, slowly, and can never read), and (optionally)
* our shadow copy that tracks what's been sent to that hardware buffer.
*/
static int dlfb_render_hline(struct dlfb_data *dev, struct urb **urb_ptr,
const char *front, char **urb_buf_ptr,
u32 byte_offset, u32 byte_width,
int *ident_ptr, int *sent_ptr)
{
const u8 *line_start, *line_end, *next_pixel;
u32 dev_addr = dev->base16 + byte_offset;
struct urb *urb = *urb_ptr;
u8 *cmd = *urb_buf_ptr;
u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length;
line_start = (u8 *) (front + byte_offset);
next_pixel = line_start;
line_end = next_pixel + byte_width;
if (dev->backing_buffer) {
int offset;
const u8 *back_start = (u8 *) (dev->backing_buffer
+ byte_offset);
*ident_ptr += dlfb_trim_hline(back_start, &next_pixel,
&byte_width);
offset = next_pixel - line_start;
line_end = next_pixel + byte_width;
dev_addr += offset;
back_start += offset;
line_start += offset;
memcpy((char *)back_start, (char *) line_start,
byte_width);
}
while (next_pixel < line_end) {
dlfb_compress_hline((const uint16_t **) &next_pixel,
(const uint16_t *) line_end, &dev_addr,
(u8 **) &cmd, (u8 *) cmd_end);
if (cmd >= cmd_end) {
int len = cmd - (u8 *) urb->transfer_buffer;
if (dlfb_submit_urb(dev, urb, len))
return 1; /* lost pixels is set */
*sent_ptr += len;
urb = dlfb_get_urb(dev);
if (!urb)
return 1; /* lost_pixels is set */
*urb_ptr = urb;
cmd = urb->transfer_buffer;
cmd_end = &cmd[urb->transfer_buffer_length];
}
}
*urb_buf_ptr = cmd;
return 0;
}
int dlfb_handle_damage(struct dlfb_data *dev, int x, int y,
int width, int height, char *data)
{
int i, ret;
char *cmd;
cycles_t start_cycles, end_cycles;
int bytes_sent = 0;
int bytes_identical = 0;
struct urb *urb;
int aligned_x;
start_cycles = get_cycles();
aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long));
width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long));
x = aligned_x;
if ((width <= 0) ||
(x + width > dev->info->var.xres) ||
(y + height > dev->info->var.yres))
return -EINVAL;
if (!atomic_read(&dev->usb_active))
return 0;
urb = dlfb_get_urb(dev);
if (!urb)
return 0;
cmd = urb->transfer_buffer;
for (i = y; i < y + height ; i++) {
const int line_offset = dev->info->fix.line_length * i;
const int byte_offset = line_offset + (x * BPP);
if (dlfb_render_hline(dev, &urb,
(char *) dev->info->fix.smem_start,
&cmd, byte_offset, width * BPP,
&bytes_identical, &bytes_sent))
goto error;
}
if (cmd > (char *) urb->transfer_buffer) {
/* Send partial buffer remaining before exiting */
int len = cmd - (char *) urb->transfer_buffer;
ret = dlfb_submit_urb(dev, urb, len);
bytes_sent += len;
} else
dlfb_urb_completion(urb);
error:
atomic_add(bytes_sent, &dev->bytes_sent);
atomic_add(bytes_identical, &dev->bytes_identical);
atomic_add(width*height*2, &dev->bytes_rendered);
end_cycles = get_cycles();
atomic_add(((unsigned int) ((end_cycles - start_cycles)
>> 10)), /* Kcycles */
&dev->cpu_kcycles_used);
return 0;
}
/*
* Path triggered by usermode clients who write to filesystem
* e.g. cat filename > /dev/fb1
* Not used by X Windows or text-mode console. But useful for testing.
* Slow because of extra copy and we must assume all pixels dirty.
*/
static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t result;
struct dlfb_data *dev = info->par;
u32 offset = (u32) *ppos;
result = fb_sys_write(info, buf, count, ppos);
if (result > 0) {
int start = max((int)(offset / info->fix.line_length) - 1, 0);
int lines = min((u32)((result / info->fix.line_length) + 1),
(u32)info->var.yres);
dlfb_handle_damage(dev, 0, start, info->var.xres,
lines, info->screen_base);
}
return result;
}
/* hardware has native COPY command (see libdlo), but not worth it for fbcon */
static void dlfb_ops_copyarea(struct fb_info *info,
const struct fb_copyarea *area)
{
struct dlfb_data *dev = info->par;
sys_copyarea(info, area);
dlfb_handle_damage(dev, area->dx, area->dy,
area->width, area->height, info->screen_base);
}
static void dlfb_ops_imageblit(struct fb_info *info,
const struct fb_image *image)
{
struct dlfb_data *dev = info->par;
sys_imageblit(info, image);
dlfb_handle_damage(dev, image->dx, image->dy,
image->width, image->height, info->screen_base);
}
static void dlfb_ops_fillrect(struct fb_info *info,
const struct fb_fillrect *rect)
{
struct dlfb_data *dev = info->par;
sys_fillrect(info, rect);
dlfb_handle_damage(dev, rect->dx, rect->dy, rect->width,
rect->height, info->screen_base);
}
/*
* NOTE: fb_defio.c is holding info->fbdefio.mutex
* Touching ANY framebuffer memory that triggers a page fault
* in fb_defio will cause a deadlock, when it also tries to
* grab the same mutex.
*/
static void dlfb_dpy_deferred_io(struct fb_info *info,
struct list_head *pagelist)
{
struct page *cur;
struct fb_deferred_io *fbdefio = info->fbdefio;
struct dlfb_data *dev = info->par;
struct urb *urb;
char *cmd;
cycles_t start_cycles, end_cycles;
int bytes_sent = 0;
int bytes_identical = 0;
int bytes_rendered = 0;
if (!fb_defio)
return;
if (!atomic_read(&dev->usb_active))
return;
start_cycles = get_cycles();
urb = dlfb_get_urb(dev);
if (!urb)
return;
cmd = urb->transfer_buffer;
/* walk the written page list and render each to device */
list_for_each_entry(cur, &fbdefio->pagelist, lru) {
if (dlfb_render_hline(dev, &urb, (char *) info->fix.smem_start,
&cmd, cur->index << PAGE_SHIFT,
PAGE_SIZE, &bytes_identical, &bytes_sent))
goto error;
bytes_rendered += PAGE_SIZE;
}
if (cmd > (char *) urb->transfer_buffer) {
/* Send partial buffer remaining before exiting */
int len = cmd - (char *) urb->transfer_buffer;
dlfb_submit_urb(dev, urb, len);
bytes_sent += len;
} else
dlfb_urb_completion(urb);
error:
atomic_add(bytes_sent, &dev->bytes_sent);
atomic_add(bytes_identical, &dev->bytes_identical);
atomic_add(bytes_rendered, &dev->bytes_rendered);
end_cycles = get_cycles();
atomic_add(((unsigned int) ((end_cycles - start_cycles)
>> 10)), /* Kcycles */
&dev->cpu_kcycles_used);
}
static int dlfb_get_edid(struct dlfb_data *dev, char *edid, int len)
{
int i;
int ret;
char *rbuf;
rbuf = kmalloc(2, GFP_KERNEL);
if (!rbuf)
return 0;
for (i = 0; i < len; i++) {
ret = usb_control_msg(dev->udev,
usb_rcvctrlpipe(dev->udev, 0), (0x02),
(0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2,
HZ);
if (ret < 1) {
pr_err("Read EDID byte %d failed err %x\n", i, ret);
i--;
break;
}
edid[i] = rbuf[1];
}
kfree(rbuf);
return i;
}
static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd,
unsigned long arg)
{
struct dlfb_data *dev = info->par;
if (!atomic_read(&dev->usb_active))
return 0;
/* TODO: Update X server to get this from sysfs instead */
if (cmd == DLFB_IOCTL_RETURN_EDID) {
void __user *edid = (void __user *)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) {
struct dloarea area;
if (copy_from_user(&area, (void __user *)arg,
sizeof(struct dloarea)))
return -EFAULT;
/*
* If we have a damage-aware client, turn fb_defio "off"
* To avoid perf imact of unnecessary 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;
if (area.x < 0)
area.x = 0;
if (area.x > info->var.xres)
area.x = info->var.xres;
if (area.y < 0)
area.y = 0;
if (area.y > info->var.yres)
area.y = info->var.yres;
dlfb_handle_damage(dev, area.x, area.y, area.w, area.h,
info->screen_base);
}
return 0;
}
/* taken from vesafb */
static int
dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green,
unsigned blue, unsigned transp, struct fb_info *info)
{
int err = 0;
if (regno >= info->cmap.len)
return 1;
if (regno < 16) {
if (info->var.red.offset == 10) {
/* 1:5:5:5 */
((u32 *) (info->pseudo_palette))[regno] =
((red & 0xf800) >> 1) |
((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11);
} else {
/* 0:5:6:5 */
((u32 *) (info->pseudo_palette))[regno] =
((red & 0xf800)) |
((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11);
}
}
return err;
}
/*
* It's common for several clients to have framebuffer open simultaneously.
* e.g. both fbcon and X. Makes things interesting.
* Assumes caller is holding info->lock (for open and release at least)
*/
static int dlfb_ops_open(struct fb_info *info, int user)
{
struct dlfb_data *dev = info->par;
/*
* fbcon aggressively connects to first framebuffer it finds,
* preventing other clients (X) from working properly. Usually
* not what the user wants. Fail by default with option to enable.
*/
if ((user == 0) && (!console))
return -EBUSY;
/* If the USB device is gone, we don't accept new opens */
if (dev->virtualized)
return -ENODEV;
dev->fb_count++;
kref_get(&dev->kref);
if (fb_defio && (info->fbdefio == NULL)) {
/* enable defio at last moment if not disabled by client */
struct fb_deferred_io *fbdefio;
fbdefio = kmalloc(sizeof(struct fb_deferred_io), GFP_KERNEL);
if (fbdefio) {
fbdefio->delay = DL_DEFIO_WRITE_DELAY;
fbdefio->deferred_io = dlfb_dpy_deferred_io;
}
info->fbdefio = fbdefio;
fb_deferred_io_init(info);
}
pr_notice("open /dev/fb%d user=%d fb_info=%p count=%d\n",
info->node, user, info, dev->fb_count);
return 0;
}
/*
* Called when all client interfaces to start transactions have been disabled,
* and all references to our device instance (dlfb_data) are released.
* Every transaction must have a reference, so we know are fully spun down
*/
static void dlfb_free(struct kref *kref)
{
struct dlfb_data *dev = container_of(kref, struct dlfb_data, kref);
/* this function will wait for all in-flight urbs to complete */
if (dev->urbs.count > 0)
dlfb_free_urb_list(dev);
if (dev->backing_buffer)
vfree(dev->backing_buffer);
kfree(dev->edid);
pr_warn("freeing dlfb_data %p\n", dev);
kfree(dev);
}
static void dlfb_release_urb_work(struct work_struct *work)
{
struct urb_node *unode = container_of(work, struct urb_node,
release_urb_work.work);
up(&unode->dev->urbs.limit_sem);
}
static void dlfb_free_framebuffer_work(struct work_struct *work)
{
struct dlfb_data *dev = container_of(work, struct dlfb_data,
free_framebuffer_work.work);
struct fb_info *info = dev->info;
int node = info->node;
unregister_framebuffer(info);
if (info->cmap.len != 0)
fb_dealloc_cmap(&info->cmap);
if (info->monspecs.modedb)
fb_destroy_modedb(info->monspecs.modedb);
if (info->screen_base)
vfree(info->screen_base);
fb_destroy_modelist(&info->modelist);
dev->info = 0;
/* Assume info structure is freed after this point */
framebuffer_release(info);
pr_warn("fb_info for /dev/fb%d has been freed\n", node);
/* ref taken in probe() as part of registering framebfufer */
kref_put(&dev->kref, dlfb_free);
}
/*
* Assumes caller is holding info->lock mutex (for open and release at least)
*/
static int dlfb_ops_release(struct fb_info *info, int user)
{
struct dlfb_data *dev = info->par;
dev->fb_count--;
/* We can't free fb_info here - fbmem will touch it when we return */
if (dev->virtualized && (dev->fb_count == 0))
schedule_delayed_work(&dev->free_framebuffer_work, HZ);
if ((dev->fb_count == 0) && (info->fbdefio)) {
fb_deferred_io_cleanup(info);
kfree(info->fbdefio);
info->fbdefio = NULL;
info->fbops->fb_mmap = dlfb_ops_mmap;
}
pr_warn("released /dev/fb%d user=%d count=%d\n",
info->node, user, dev->fb_count);
kref_put(&dev->kref, dlfb_free);
return 0;
}
/*
* Check whether a video mode is supported by the DisplayLink chip
* We start from monitor's modes, so don't need to filter that here
*/
static int dlfb_is_valid_mode(struct fb_videomode *mode,
struct fb_info *info)
{
struct dlfb_data *dev = info->par;
if (mode->xres * mode->yres > dev->sku_pixel_limit) {
pr_warn("%dx%d beyond chip capabilities\n",
mode->xres, mode->yres);
return 0;
}
pr_info("%dx%d valid mode\n", mode->xres, mode->yres);
return 1;
}
static void dlfb_var_color_format(struct fb_var_screeninfo *var)
{
const struct fb_bitfield red = { 11, 5, 0 };
const struct fb_bitfield green = { 5, 6, 0 };
const struct fb_bitfield blue = { 0, 5, 0 };
var->bits_per_pixel = 16;
var->red = red;
var->green = green;
var->blue = blue;
}
static int dlfb_ops_check_var(struct fb_var_screeninfo *var,
struct fb_info *info)
{
struct fb_videomode mode;
/* TODO: support dynamically changing framebuffer size */
if ((var->xres * var->yres * 2) > info->fix.smem_len)
return -EINVAL;
/* set device-specific elements of var unrelated to mode */
dlfb_var_color_format(var);
fb_var_to_videomode(&mode, var);
if (!dlfb_is_valid_mode(&mode, info))
return -EINVAL;
return 0;
}
static int dlfb_ops_set_par(struct fb_info *info)
{
struct dlfb_data *dev = info->par;
int result;
u16 *pix_framebuffer;
int i;
pr_notice("set_par mode %dx%d\n", info->var.xres, info->var.yres);
result = dlfb_set_video_mode(dev, &info->var);
if ((result == 0) && (dev->fb_count == 0)) {
/* paint greenscreen */
pix_framebuffer = (u16 *) info->screen_base;
for (i = 0; i < info->fix.smem_len / 2; i++)
pix_framebuffer[i] = 0x37e6;
dlfb_handle_damage(dev, 0, 0, info->var.xres, info->var.yres,
info->screen_base);
}
return result;
}
/* To fonzi the jukebox (e.g. make blanking changes take effect) */
static char *dlfb_dummy_render(char *buf)
{
*buf++ = 0xAF;
*buf++ = 0x6A; /* copy */
*buf++ = 0x00; /* from address*/
*buf++ = 0x00;
*buf++ = 0x00;
*buf++ = 0x01; /* one pixel */
*buf++ = 0x00; /* to address */
*buf++ = 0x00;
*buf++ = 0x00;
return buf;
}
/*
* 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;
char *bufptr;
struct urb *urb;
pr_info("/dev/fb%d FB_BLANK mode %d --> %d\n",
info->node, dev->blank_mode, blank_mode);
if ((dev->blank_mode == FB_BLANK_POWERDOWN) &&
(blank_mode != FB_BLANK_POWERDOWN)) {
/* returning from powerdown requires a fresh modeset */
dlfb_set_video_mode(dev, &info->var);
}
urb = dlfb_get_urb(dev);
if (!urb)
return 0;
bufptr = (char *) urb->transfer_buffer;
bufptr = dlfb_vidreg_lock(bufptr);
bufptr = dlfb_blanking(bufptr, blank_mode);
bufptr = dlfb_vidreg_unlock(bufptr);
/* seems like a render op is needed to have blank change take effect */
bufptr = dlfb_dummy_render(bufptr);
dlfb_submit_urb(dev, urb, bufptr -
(char *) urb->transfer_buffer);
dev->blank_mode = blank_mode;
return 0;
}
static struct fb_ops dlfb_ops = {
.owner = THIS_MODULE,
.fb_read = fb_sys_read,
.fb_write = dlfb_ops_write,
.fb_setcolreg = dlfb_ops_setcolreg,
.fb_fillrect = dlfb_ops_fillrect,
.fb_copyarea = dlfb_ops_copyarea,
.fb_imageblit = dlfb_ops_imageblit,
.fb_mmap = dlfb_ops_mmap,
.fb_ioctl = dlfb_ops_ioctl,
.fb_open = dlfb_ops_open,
.fb_release = dlfb_ops_release,
.fb_blank = dlfb_ops_blank,
.fb_check_var = dlfb_ops_check_var,
.fb_set_par = dlfb_ops_set_par,
};
/*
* Assumes &info->lock held by caller
* Assumes no active clients have framebuffer open
*/
static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info)
{
int retval = -ENOMEM;
int old_len = info->fix.smem_len;
int new_len;
unsigned char *old_fb = info->screen_base;
unsigned char *new_fb;
unsigned char *new_back = 0;
pr_warn("Reallocating framebuffer. Addresses will change!\n");
new_len = info->fix.line_length * info->var.yres;
if (PAGE_ALIGN(new_len) > old_len) {
/*
* Alloc system memory for virtual framebuffer
*/
new_fb = vmalloc(new_len);
if (!new_fb) {
pr_err("Virtual framebuffer alloc failed\n");
goto error;
}
if (info->screen_base) {
memcpy(new_fb, old_fb, old_len);
vfree(info->screen_base);
}
info->screen_base = new_fb;
info->fix.smem_len = PAGE_ALIGN(new_len);
info->fix.smem_start = (unsigned long) new_fb;
info->flags = udlfb_info_flags;
/*
* Second framebuffer copy to mirror the framebuffer state
* on the physical USB device. We can function without this.
* But with imperfect damage info we may send pixels over USB
* that were, in fact, unchanged - wasting limited USB bandwidth
*/
if (shadow)
new_back = vzalloc(new_len);
if (!new_back)
pr_info("No shadow/backing buffer allocated\n");
else {
if (dev->backing_buffer)
vfree(dev->backing_buffer);
dev->backing_buffer = new_back;
}
}
retval = 0;
error:
return retval;
}
/*
* 1) Get EDID from hw, or use sw default
* 2) Parse into various fb_info structs
* 3) Allocate virtual framebuffer memory to back highest res mode
*
* Parses EDID into three places used by various parts of fbdev:
* fb_var_screeninfo contains the timing of the monitor's preferred mode
* fb_info.monspecs is full parsed EDID info, including monspecs.modedb
* fb_info.modelist is a linked list of all monitor & VESA modes which work
*
* If EDID is not readable/valid, then modelist is all VESA modes,
* monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode
* Returns 0 if successful
*/
static int dlfb_setup_modes(struct dlfb_data *dev,
struct fb_info *info,
char *default_edid, size_t default_edid_size)
{
int i;
const struct fb_videomode *default_vmode = NULL;
int result = 0;
char *edid;
int tries = 3;
if (info->dev) /* only use mutex if info has been registered */
mutex_lock(&info->lock);
edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
if (!edid) {
result = -ENOMEM;
goto error;
}
fb_destroy_modelist(&info->modelist);
memset(&info->monspecs, 0, sizeof(info->monspecs));
/*
* Try to (re)read EDID from hardware first
* EDID data may return, but not parse as valid
* Try again a few times, in case of e.g. analog cable noise
*/
while (tries--) {
i = dlfb_get_edid(dev, edid, EDID_LENGTH);
if (i >= EDID_LENGTH)
fb_edid_to_monspecs(edid, &info->monspecs);
if (info->monspecs.modedb_len > 0) {
dev->edid = edid;
dev->edid_size = i;
break;
}
}
/* If that fails, use a previously returned EDID if available */
if (info->monspecs.modedb_len == 0) {
pr_err("Unable to get valid EDID from device/display\n");
if (dev->edid) {
fb_edid_to_monspecs(dev->edid, &info->monspecs);
if (info->monspecs.modedb_len > 0)
pr_err("Using previously queried EDID\n");
}
}
/* If that fails, use the default EDID we were handed */
if (info->monspecs.modedb_len == 0) {
if (default_edid_size >= EDID_LENGTH) {
fb_edid_to_monspecs(default_edid, &info->monspecs);
if (info->monspecs.modedb_len > 0) {
memcpy(edid, default_edid, default_edid_size);
dev->edid = edid;
dev->edid_size = default_edid_size;
pr_err("Using default/backup EDID\n");
}
}
}
/* If we've got modes, let's pick a best default mode */
if (info->monspecs.modedb_len > 0) {
for (i = 0; i < info->monspecs.modedb_len; i++) {
if (dlfb_is_valid_mode(&info->monspecs.modedb[i], info))
fb_add_videomode(&info->monspecs.modedb[i],
&info->modelist);
else {
if (i == 0)
/* if we've removed top/best mode */
info->monspecs.misc
&= ~FB_MISC_1ST_DETAIL;
}
}
default_vmode = fb_find_best_display(&info->monspecs,
&info->modelist);
}
/* If everything else has failed, fall back to safe default mode */
if (default_vmode == NULL) {
struct fb_videomode fb_vmode = {0};
/*
* Add the standard VESA modes to our modelist
* Since we don't have EDID, there may be modes that
* overspec monitor and/or are incorrect aspect ratio, etc.
* But at least the user has a chance to choose
*/
for (i = 0; i < VESA_MODEDB_SIZE; i++) {
if (dlfb_is_valid_mode((struct fb_videomode *)
&vesa_modes[i], info))
fb_add_videomode(&vesa_modes[i],
&info->modelist);
}
/*
* default to resolution safe for projectors
* (since they are most common case without EDID)
*/
fb_vmode.xres = 800;
fb_vmode.yres = 600;
fb_vmode.refresh = 60;
default_vmode = fb_find_nearest_mode(&fb_vmode,
&info->modelist);
}
/* If we have good mode and no active clients*/
if ((default_vmode != NULL) && (dev->fb_count == 0)) {
fb_videomode_to_var(&info->var, default_vmode);
dlfb_var_color_format(&info->var);
/*
* with mode size info, we can now alloc our framebuffer.
*/
memcpy(&info->fix, &dlfb_fix, sizeof(dlfb_fix));
info->fix.line_length = info->var.xres *
(info->var.bits_per_pixel / 8);
result = dlfb_realloc_framebuffer(dev, info);
} else
result = -EINVAL;
error:
if (edid && (dev->edid != edid))
kfree(edid);
if (info->dev)
mutex_unlock(&info->lock);
return result;
}
static ssize_t metrics_bytes_rendered_show(struct device *fbdev,
struct device_attribute *a, char *buf) {
struct fb_info *fb_info = dev_get_drvdata(fbdev);
struct dlfb_data *dev = fb_info->par;
return snprintf(buf, PAGE_SIZE, "%u\n",
atomic_read(&dev->bytes_rendered));
}
static ssize_t metrics_bytes_identical_show(struct device *fbdev,
struct device_attribute *a, char *buf) {
struct fb_info *fb_info = dev_get_drvdata(fbdev);
struct dlfb_data *dev = fb_info->par;
return snprintf(buf, PAGE_SIZE, "%u\n",
atomic_read(&dev->bytes_identical));
}
static ssize_t metrics_bytes_sent_show(struct device *fbdev,
struct device_attribute *a, char *buf) {
struct fb_info *fb_info = dev_get_drvdata(fbdev);
struct dlfb_data *dev = fb_info->par;
return snprintf(buf, PAGE_SIZE, "%u\n",
atomic_read(&dev->bytes_sent));
}
static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev,
struct device_attribute *a, char *buf) {
struct fb_info *fb_info = dev_get_drvdata(fbdev);
struct dlfb_data *dev = fb_info->par;
return snprintf(buf, PAGE_SIZE, "%u\n",
atomic_read(&dev->cpu_kcycles_used));
}
static ssize_t edid_show(
struct file *filp,
struct kobject *kobj, struct bin_attribute *a,
char *buf, loff_t off, size_t count) {
struct device *fbdev = container_of(kobj, struct device, kobj);
struct fb_info *fb_info = dev_get_drvdata(fbdev);
struct dlfb_data *dev = fb_info->par;
if (dev->edid == NULL)
return 0;
if ((off >= dev->edid_size) || (count > dev->edid_size))
return 0;
if (off + count > dev->edid_size)
count = dev->edid_size - off;
pr_info("sysfs edid copy %p to %p, %d bytes\n",
dev->edid, buf, (int) count);
memcpy(buf, dev->edid, count);
return count;
}
static ssize_t edid_store(
struct file *filp,
struct kobject *kobj, struct bin_attribute *a,
char *src, loff_t src_off, size_t src_size) {
struct device *fbdev = container_of(kobj, struct device, kobj);
struct fb_info *fb_info = dev_get_drvdata(fbdev);
struct dlfb_data *dev = fb_info->par;
/* We only support write of entire EDID at once, no offset*/
if ((src_size != EDID_LENGTH) || (src_off != 0))
return 0;
dlfb_setup_modes(dev, fb_info, src, src_size);
if (dev->edid && (memcmp(src, dev->edid, src_size) == 0)) {
pr_info("sysfs written EDID is new default\n");
dlfb_ops_set_par(fb_info);
return src_size;
} else
return 0;
}
static ssize_t metrics_reset_store(struct device *fbdev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(fbdev);
struct dlfb_data *dev = fb_info->par;
atomic_set(&dev->bytes_rendered, 0);
atomic_set(&dev->bytes_identical, 0);
atomic_set(&dev->bytes_sent, 0);
atomic_set(&dev->cpu_kcycles_used, 0);
return count;
}
static struct bin_attribute edid_attr = {
.attr.name = "edid",
.attr.mode = 0666,
.size = EDID_LENGTH,
.read = edid_show,
.write = edid_store
};
static struct device_attribute fb_device_attrs[] = {
__ATTR_RO(metrics_bytes_rendered),
__ATTR_RO(metrics_bytes_identical),
__ATTR_RO(metrics_bytes_sent),
__ATTR_RO(metrics_cpu_kcycles_used),
__ATTR(metrics_reset, S_IWUSR, NULL, metrics_reset_store),
};
/*
* This is necessary before we can communicate with the display controller.
*/
static int dlfb_select_std_channel(struct dlfb_data *dev)
{
int ret;
u8 set_def_chn[] = { 0x57, 0xCD, 0xDC, 0xA7,
0x1C, 0x88, 0x5E, 0x15,
0x60, 0xFE, 0xC6, 0x97,
0x16, 0x3D, 0x47, 0xF2 };
ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
NR_USB_REQUEST_CHANNEL,
(USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT);
return ret;
}
static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
struct usb_interface *interface)
{
char *desc;
char *buf;
char *desc_end;
int total_len = 0;
buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);
if (!buf)
return false;
desc = buf;
total_len = usb_get_descriptor(interface_to_usbdev(interface),
0x5f, /* vendor specific */
0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
/* if not found, look in configuration descriptor */
if (total_len < 0) {
if (0 == usb_get_extra_descriptor(interface->cur_altsetting,
0x5f, &desc))
total_len = (int) desc[0];
}
if (total_len > 5) {
pr_info("vendor descriptor length:%x data:%02x %02x %02x %02x" \
"%02x %02x %02x %02x %02x %02x %02x\n",
total_len, desc[0],
desc[1], desc[2], desc[3], desc[4], desc[5], desc[6],
desc[7], desc[8], desc[9], desc[10]);
if ((desc[0] != total_len) || /* descriptor length */
(desc[1] != 0x5f) || /* vendor descriptor type */
(desc[2] != 0x01) || /* version (2 bytes) */
(desc[3] != 0x00) ||
(desc[4] != total_len - 2)) /* length after type */
goto unrecognized;
desc_end = desc + total_len;
desc += 5; /* the fixed header we've already parsed */
while (desc < desc_end) {
u8 length;
u16 key;
key = *((u16 *) desc);
desc += sizeof(u16);
length = *desc;
desc++;
switch (key) {
case 0x0200: { /* max_area */
u32 max_area;
max_area = le32_to_cpu(*((u32 *)desc));
pr_warn("DL chip limited to %d pixel modes\n",
max_area);
dev->sku_pixel_limit = max_area;
break;
}
default:
break;
}
desc += length;
}
} else {
pr_info("vendor descriptor not available (%d)\n", total_len);
}
goto success;
unrecognized:
/* allow udlfb to load for now even if firmware unrecognized */
pr_err("Unrecognized vendor firmware descriptor\n");
success:
kfree(buf);
return true;
}
static int dlfb_usb_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
struct usb_device *usbdev;
struct dlfb_data *dev = 0;
struct fb_info *info = 0;
int retval = -ENOMEM;
int i;
/* usb initialization */
usbdev = interface_to_usbdev(interface);
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (dev == NULL) {
err("dlfb_usb_probe: failed alloc of dev struct\n");
goto error;
}
/* we need to wait for both usb and fbdev to spin down on disconnect */
kref_init(&dev->kref); /* matching kref_put in usb .disconnect fn */
kref_get(&dev->kref); /* matching kref_put in free_framebuffer_work */
dev->udev = usbdev;
dev->gdev = &usbdev->dev; /* our generic struct device * */
usb_set_intfdata(interface, dev);
pr_info("%s %s - serial #%s\n",
usbdev->manufacturer, usbdev->product, usbdev->serial);
pr_info("vid_%04x&pid_%04x&rev_%04x driver's dlfb_data struct at %p\n",
usbdev->descriptor.idVendor, usbdev->descriptor.idProduct,
usbdev->descriptor.bcdDevice, dev);
pr_info("console enable=%d\n", console);
pr_info("fb_defio enable=%d\n", fb_defio);
pr_info("shadow enable=%d\n", shadow);
dev->sku_pixel_limit = 2048 * 1152; /* default to maximum */
if (!dlfb_parse_vendor_descriptor(dev, interface)) {
pr_err("firmware not recognized. Assume incompatible device\n");
goto error;
}
if (!dlfb_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
retval = -ENOMEM;
pr_err("dlfb_alloc_urb_list failed\n");
goto error;
}
/* We don't register a new USB class. Our client interface is fbdev */
/* allocates framebuffer driver structure, not framebuffer memory */
info = framebuffer_alloc(0, &interface->dev);
if (!info) {
retval = -ENOMEM;
pr_err("framebuffer_alloc failed\n");
goto error;
}
dev->info = info;
info->par = dev;
info->pseudo_palette = dev->pseudo_palette;
info->fbops = &dlfb_ops;
retval = fb_alloc_cmap(&info->cmap, 256, 0);
if (retval < 0) {
pr_err("fb_alloc_cmap failed %x\n", retval);
goto error;
}
INIT_DELAYED_WORK(&dev->free_framebuffer_work,
dlfb_free_framebuffer_work);
INIT_LIST_HEAD(&info->modelist);
retval = dlfb_setup_modes(dev, info, NULL, 0);
if (retval != 0) {
pr_err("unable to find common mode for display and adapter\n");
goto error;
}
/* ready to begin using device */
atomic_set(&dev->usb_active, 1);
dlfb_select_std_channel(dev);
dlfb_ops_check_var(&info->var, info);
dlfb_ops_set_par(info);
retval = register_framebuffer(info);
if (retval < 0) {
pr_err("register_framebuffer failed %d\n", retval);
goto error;
}
for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) {
retval = device_create_file(info->dev, &fb_device_attrs[i]);
if (retval) {
pr_err("device_create_file failed %d\n", retval);
goto err_del_attrs;
}
}
retval = device_create_bin_file(info->dev, &edid_attr);
if (retval) {
pr_err("device_create_bin_file failed %d\n", retval);
goto err_del_attrs;
}
pr_info("DisplayLink USB device /dev/fb%d attached. %dx%d resolution."
" Using %dK framebuffer memory\n", info->node,
info->var.xres, info->var.yres,
((dev->backing_buffer) ?
info->fix.smem_len * 2 : info->fix.smem_len) >> 10);
return 0;
err_del_attrs:
for (i -= 1; i >= 0; i--)
device_remove_file(info->dev, &fb_device_attrs[i]);
error:
if (dev) {
if (info) {
if (info->cmap.len != 0)
fb_dealloc_cmap(&info->cmap);
if (info->monspecs.modedb)
fb_destroy_modedb(info->monspecs.modedb);
if (info->screen_base)
vfree(info->screen_base);
fb_destroy_modelist(&info->modelist);
framebuffer_release(info);
}
if (dev->backing_buffer)
vfree(dev->backing_buffer);
kref_put(&dev->kref, dlfb_free); /* ref for framebuffer */
kref_put(&dev->kref, dlfb_free); /* last ref from kref_init */
/* dev has been deallocated. Do not dereference */
}
return retval;
}
static void dlfb_usb_disconnect(struct usb_interface *interface)
{
struct dlfb_data *dev;
struct fb_info *info;
int i;
dev = usb_get_intfdata(interface);
info = dev->info;
pr_info("USB disconnect starting\n");
/* we virtualize until all fb clients release. Then we free */
dev->virtualized = true;
/* When non-active we'll update virtual framebuffer, but no new urbs */
atomic_set(&dev->usb_active, 0);
/* remove udlfb's sysfs interfaces */
for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
device_remove_file(info->dev, &fb_device_attrs[i]);
device_remove_bin_file(info->dev, &edid_attr);
usb_set_intfdata(interface, NULL);
/* if clients still have us open, will be freed on last close */
if (dev->fb_count == 0)
schedule_delayed_work(&dev->free_framebuffer_work, 0);
/* release reference taken by kref_init in probe() */
kref_put(&dev->kref, dlfb_free);
/* consider dlfb_data freed */
return;
}
static struct usb_driver dlfb_driver = {
.name = "udlfb",
.probe = dlfb_usb_probe,
.disconnect = dlfb_usb_disconnect,
.id_table = id_table,
};
module_usb_driver(dlfb_driver);
static void dlfb_urb_completion(struct urb *urb)
{
struct urb_node *unode = urb->context;
struct dlfb_data *dev = unode->dev;
unsigned long flags;
/* sync/async unlink faults aren't errors */
if (urb->status) {
if (!(urb->status == -ENOENT ||
urb->status == -ECONNRESET ||
urb->status == -ESHUTDOWN)) {
pr_err("%s - nonzero write bulk status received: %d\n",
__func__, urb->status);
atomic_set(&dev->lost_pixels, 1);
}
}
urb->transfer_buffer_length = dev->urbs.size; /* reset to actual */
spin_lock_irqsave(&dev->urbs.lock, flags);
list_add_tail(&unode->entry, &dev->urbs.list);
dev->urbs.available++;
spin_unlock_irqrestore(&dev->urbs.lock, flags);
/*
* When using fb_defio, we deadlock if up() is called
* while another is waiting. So queue to another process.
*/
if (fb_defio)
schedule_delayed_work(&unode->release_urb_work, 0);
else
up(&dev->urbs.limit_sem);
}
static void dlfb_free_urb_list(struct dlfb_data *dev)
{
int count = dev->urbs.count;
struct list_head *node;
struct urb_node *unode;
struct urb *urb;
int ret;
unsigned long flags;
pr_notice("Waiting for completes and freeing all render urbs\n");
/* keep waiting and freeing, until we've got 'em all */
while (count--) {
/* Getting interrupted means a leak, but ok at shutdown*/
ret = down_interruptible(&dev->urbs.limit_sem);
if (ret)
break;
spin_lock_irqsave(&dev->urbs.lock, flags);
node = dev->urbs.list.next; /* have reserved one with sem */
list_del_init(node);
spin_unlock_irqrestore(&dev->urbs.lock, flags);
unode = list_entry(node, struct urb_node, entry);
urb = unode->urb;
/* Free each separately allocated piece */
usb_free_coherent(urb->dev, dev->urbs.size,
urb->transfer_buffer, urb->transfer_dma);
usb_free_urb(urb);
kfree(node);
}
}
static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size)
{
int i = 0;
struct urb *urb;
struct urb_node *unode;
char *buf;
spin_lock_init(&dev->urbs.lock);
dev->urbs.size = size;
INIT_LIST_HEAD(&dev->urbs.list);
while (i < count) {
unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL);
if (!unode)
break;
unode->dev = dev;
INIT_DELAYED_WORK(&unode->release_urb_work,
dlfb_release_urb_work);
urb = usb_alloc_urb(0, GFP_KERNEL);
if (!urb) {
kfree(unode);
break;
}
unode->urb = urb;
buf = usb_alloc_coherent(dev->udev, MAX_TRANSFER, GFP_KERNEL,
&urb->transfer_dma);
if (!buf) {
kfree(unode);
usb_free_urb(urb);
break;
}
/* urb->transfer_buffer_length set to actual before submit */
usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 1),
buf, size, dlfb_urb_completion, unode);
urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
list_add_tail(&unode->entry, &dev->urbs.list);
i++;
}
sema_init(&dev->urbs.limit_sem, i);
dev->urbs.count = i;
dev->urbs.available = i;
pr_notice("allocated %d %d byte urbs\n", i, (int) size);
return i;
}
static struct urb *dlfb_get_urb(struct dlfb_data *dev)
{
int ret = 0;
struct list_head *entry;
struct urb_node *unode;
struct urb *urb = NULL;
unsigned long flags;
/* Wait for an in-flight buffer to complete and get re-queued */
ret = down_timeout(&dev->urbs.limit_sem, GET_URB_TIMEOUT);
if (ret) {
atomic_set(&dev->lost_pixels, 1);
pr_warn("wait for urb interrupted: %x available: %d\n",
ret, dev->urbs.available);
goto error;
}
spin_lock_irqsave(&dev->urbs.lock, flags);
BUG_ON(list_empty(&dev->urbs.list)); /* reserved one with limit_sem */
entry = dev->urbs.list.next;
list_del_init(entry);
dev->urbs.available--;
spin_unlock_irqrestore(&dev->urbs.lock, flags);
unode = list_entry(entry, struct urb_node, entry);
urb = unode->urb;
error:
return urb;
}
static int dlfb_submit_urb(struct dlfb_data *dev, struct urb *urb, size_t len)
{
int ret;
BUG_ON(len > dev->urbs.size);
urb->transfer_buffer_length = len; /* set to actual payload len */
ret = usb_submit_urb(urb, GFP_KERNEL);
if (ret) {
dlfb_urb_completion(urb); /* because no one else will */
atomic_set(&dev->lost_pixels, 1);
pr_err("usb_submit_urb error %x\n", ret);
}
return ret;
}
module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
MODULE_PARM_DESC(console, "Allow fbcon to open framebuffer");
module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
MODULE_PARM_DESC(fb_defio, "Page fault detection of mmap writes");
module_param(shadow, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);
MODULE_PARM_DESC(shadow, "Shadow vid mem. Disable to save mem but lose perf");
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");