Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / video / fbdev / core / fbmem.c
diff --git a/kernel/drivers/video/fbdev/core/fbmem.c b/kernel/drivers/video/fbdev/core/fbmem.c
new file mode 100644 (file)
index 0000000..0705d88
--- /dev/null
@@ -0,0 +1,1911 @@
+/*
+ *  linux/drivers/video/fbmem.c
+ *
+ *  Copyright (C) 1994 Martin Schaller
+ *
+ *     2001 - Documented with DocBook
+ *     - Brad Douglas <brad@neruo.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/module.h>
+
+#include <linux/compat.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/vt.h>
+#include <linux/init.h>
+#include <linux/linux_logo.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/console.h>
+#include <linux/kmod.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/efi.h>
+#include <linux/fb.h>
+
+#include <asm/fb.h>
+
+
+    /*
+     *  Frame buffer device initialization and setup routines
+     */
+
+#define FBPIXMAPSIZE   (1024 * 8)
+
+static DEFINE_MUTEX(registration_lock);
+
+struct fb_info *registered_fb[FB_MAX] __read_mostly;
+EXPORT_SYMBOL(registered_fb);
+
+int num_registered_fb __read_mostly;
+EXPORT_SYMBOL(num_registered_fb);
+
+static struct fb_info *get_fb_info(unsigned int idx)
+{
+       struct fb_info *fb_info;
+
+       if (idx >= FB_MAX)
+               return ERR_PTR(-ENODEV);
+
+       mutex_lock(&registration_lock);
+       fb_info = registered_fb[idx];
+       if (fb_info)
+               atomic_inc(&fb_info->count);
+       mutex_unlock(&registration_lock);
+
+       return fb_info;
+}
+
+static void put_fb_info(struct fb_info *fb_info)
+{
+       if (!atomic_dec_and_test(&fb_info->count))
+               return;
+       if (fb_info->fbops->fb_destroy)
+               fb_info->fbops->fb_destroy(fb_info);
+}
+
+int lock_fb_info(struct fb_info *info)
+{
+       mutex_lock(&info->lock);
+       if (!info->fbops) {
+               mutex_unlock(&info->lock);
+               return 0;
+       }
+       return 1;
+}
+EXPORT_SYMBOL(lock_fb_info);
+
+/*
+ * Helpers
+ */
+
+int fb_get_color_depth(struct fb_var_screeninfo *var,
+                      struct fb_fix_screeninfo *fix)
+{
+       int depth = 0;
+
+       if (fix->visual == FB_VISUAL_MONO01 ||
+           fix->visual == FB_VISUAL_MONO10)
+               depth = 1;
+       else {
+               if (var->green.length == var->blue.length &&
+                   var->green.length == var->red.length &&
+                   var->green.offset == var->blue.offset &&
+                   var->green.offset == var->red.offset)
+                       depth = var->green.length;
+               else
+                       depth = var->green.length + var->red.length +
+                               var->blue.length;
+       }
+
+       return depth;
+}
+EXPORT_SYMBOL(fb_get_color_depth);
+
+/*
+ * Data padding functions.
+ */
+void fb_pad_aligned_buffer(u8 *dst, u32 d_pitch, u8 *src, u32 s_pitch, u32 height)
+{
+       __fb_pad_aligned_buffer(dst, d_pitch, src, s_pitch, height);
+}
+EXPORT_SYMBOL(fb_pad_aligned_buffer);
+
+void fb_pad_unaligned_buffer(u8 *dst, u32 d_pitch, u8 *src, u32 idx, u32 height,
+                               u32 shift_high, u32 shift_low, u32 mod)
+{
+       u8 mask = (u8) (0xfff << shift_high), tmp;
+       int i, j;
+
+       for (i = height; i--; ) {
+               for (j = 0; j < idx; j++) {
+                       tmp = dst[j];
+                       tmp &= mask;
+                       tmp |= *src >> shift_low;
+                       dst[j] = tmp;
+                       tmp = *src << shift_high;
+                       dst[j+1] = tmp;
+                       src++;
+               }
+               tmp = dst[idx];
+               tmp &= mask;
+               tmp |= *src >> shift_low;
+               dst[idx] = tmp;
+               if (shift_high < mod) {
+                       tmp = *src << shift_high;
+                       dst[idx+1] = tmp;
+               }
+               src++;
+               dst += d_pitch;
+       }
+}
+EXPORT_SYMBOL(fb_pad_unaligned_buffer);
+
+/*
+ * we need to lock this section since fb_cursor
+ * may use fb_imageblit()
+ */
+char* fb_get_buffer_offset(struct fb_info *info, struct fb_pixmap *buf, u32 size)
+{
+       u32 align = buf->buf_align - 1, offset;
+       char *addr = buf->addr;
+
+       /* If IO mapped, we need to sync before access, no sharing of
+        * the pixmap is done
+        */
+       if (buf->flags & FB_PIXMAP_IO) {
+               if (info->fbops->fb_sync && (buf->flags & FB_PIXMAP_SYNC))
+                       info->fbops->fb_sync(info);
+               return addr;
+       }
+
+       /* See if we fit in the remaining pixmap space */
+       offset = buf->offset + align;
+       offset &= ~align;
+       if (offset + size > buf->size) {
+               /* We do not fit. In order to be able to re-use the buffer,
+                * we must ensure no asynchronous DMA'ing or whatever operation
+                * is in progress, we sync for that.
+                */
+               if (info->fbops->fb_sync && (buf->flags & FB_PIXMAP_SYNC))
+                       info->fbops->fb_sync(info);
+               offset = 0;
+       }
+       buf->offset = offset + size;
+       addr += offset;
+
+       return addr;
+}
+EXPORT_SYMBOL(fb_get_buffer_offset);
+
+#ifdef CONFIG_LOGO
+
+static inline unsigned safe_shift(unsigned d, int n)
+{
+       return n < 0 ? d >> -n : d << n;
+}
+
+static void fb_set_logocmap(struct fb_info *info,
+                                  const struct linux_logo *logo)
+{
+       struct fb_cmap palette_cmap;
+       u16 palette_green[16];
+       u16 palette_blue[16];
+       u16 palette_red[16];
+       int i, j, n;
+       const unsigned char *clut = logo->clut;
+
+       palette_cmap.start = 0;
+       palette_cmap.len = 16;
+       palette_cmap.red = palette_red;
+       palette_cmap.green = palette_green;
+       palette_cmap.blue = palette_blue;
+       palette_cmap.transp = NULL;
+
+       for (i = 0; i < logo->clutsize; i += n) {
+               n = logo->clutsize - i;
+               /* palette_cmap provides space for only 16 colors at once */
+               if (n > 16)
+                       n = 16;
+               palette_cmap.start = 32 + i;
+               palette_cmap.len = n;
+               for (j = 0; j < n; ++j) {
+                       palette_cmap.red[j] = clut[0] << 8 | clut[0];
+                       palette_cmap.green[j] = clut[1] << 8 | clut[1];
+                       palette_cmap.blue[j] = clut[2] << 8 | clut[2];
+                       clut += 3;
+               }
+               fb_set_cmap(&palette_cmap, info);
+       }
+}
+
+static void  fb_set_logo_truepalette(struct fb_info *info,
+                                           const struct linux_logo *logo,
+                                           u32 *palette)
+{
+       static const unsigned char mask[] = { 0,0x80,0xc0,0xe0,0xf0,0xf8,0xfc,0xfe,0xff };
+       unsigned char redmask, greenmask, bluemask;
+       int redshift, greenshift, blueshift;
+       int i;
+       const unsigned char *clut = logo->clut;
+
+       /*
+        * We have to create a temporary palette since console palette is only
+        * 16 colors long.
+        */
+       /* Bug: Doesn't obey msb_right ... (who needs that?) */
+       redmask   = mask[info->var.red.length   < 8 ? info->var.red.length   : 8];
+       greenmask = mask[info->var.green.length < 8 ? info->var.green.length : 8];
+       bluemask  = mask[info->var.blue.length  < 8 ? info->var.blue.length  : 8];
+       redshift   = info->var.red.offset   - (8 - info->var.red.length);
+       greenshift = info->var.green.offset - (8 - info->var.green.length);
+       blueshift  = info->var.blue.offset  - (8 - info->var.blue.length);
+
+       for ( i = 0; i < logo->clutsize; i++) {
+               palette[i+32] = (safe_shift((clut[0] & redmask), redshift) |
+                                safe_shift((clut[1] & greenmask), greenshift) |
+                                safe_shift((clut[2] & bluemask), blueshift));
+               clut += 3;
+       }
+}
+
+static void fb_set_logo_directpalette(struct fb_info *info,
+                                            const struct linux_logo *logo,
+                                            u32 *palette)
+{
+       int redshift, greenshift, blueshift;
+       int i;
+
+       redshift = info->var.red.offset;
+       greenshift = info->var.green.offset;
+       blueshift = info->var.blue.offset;
+
+       for (i = 32; i < 32 + logo->clutsize; i++)
+               palette[i] = i << redshift | i << greenshift | i << blueshift;
+}
+
+static void fb_set_logo(struct fb_info *info,
+                              const struct linux_logo *logo, u8 *dst,
+                              int depth)
+{
+       int i, j, k;
+       const u8 *src = logo->data;
+       u8 xor = (info->fix.visual == FB_VISUAL_MONO01) ? 0xff : 0;
+       u8 fg = 1, d;
+
+       switch (fb_get_color_depth(&info->var, &info->fix)) {
+       case 1:
+               fg = 1;
+               break;
+       case 2:
+               fg = 3;
+               break;
+       default:
+               fg = 7;
+               break;
+       }
+
+       if (info->fix.visual == FB_VISUAL_MONO01 ||
+           info->fix.visual == FB_VISUAL_MONO10)
+               fg = ~((u8) (0xfff << info->var.green.length));
+
+       switch (depth) {
+       case 4:
+               for (i = 0; i < logo->height; i++)
+                       for (j = 0; j < logo->width; src++) {
+                               *dst++ = *src >> 4;
+                               j++;
+                               if (j < logo->width) {
+                                       *dst++ = *src & 0x0f;
+                                       j++;
+                               }
+                       }
+               break;
+       case 1:
+               for (i = 0; i < logo->height; i++) {
+                       for (j = 0; j < logo->width; src++) {
+                               d = *src ^ xor;
+                               for (k = 7; k >= 0; k--) {
+                                       *dst++ = ((d >> k) & 1) ? fg : 0;
+                                       j++;
+                               }
+                       }
+               }
+               break;
+       }
+}
+
+/*
+ * Three (3) kinds of logo maps exist.  linux_logo_clut224 (>16 colors),
+ * linux_logo_vga16 (16 colors) and linux_logo_mono (2 colors).  Depending on
+ * the visual format and color depth of the framebuffer, the DAC, the
+ * pseudo_palette, and the logo data will be adjusted accordingly.
+ *
+ * Case 1 - linux_logo_clut224:
+ * Color exceeds the number of console colors (16), thus we set the hardware DAC
+ * using fb_set_cmap() appropriately.  The "needs_cmapreset"  flag will be set.
+ *
+ * For visuals that require color info from the pseudo_palette, we also construct
+ * one for temporary use. The "needs_directpalette" or "needs_truepalette" flags
+ * will be set.
+ *
+ * Case 2 - linux_logo_vga16:
+ * The number of colors just matches the console colors, thus there is no need
+ * to set the DAC or the pseudo_palette.  However, the bitmap is packed, ie,
+ * each byte contains color information for two pixels (upper and lower nibble).
+ * To be consistent with fb_imageblit() usage, we therefore separate the two
+ * nibbles into separate bytes. The "depth" flag will be set to 4.
+ *
+ * Case 3 - linux_logo_mono:
+ * This is similar with Case 2.  Each byte contains information for 8 pixels.
+ * We isolate each bit and expand each into a byte. The "depth" flag will
+ * be set to 1.
+ */
+static struct logo_data {
+       int depth;
+       int needs_directpalette;
+       int needs_truepalette;
+       int needs_cmapreset;
+       const struct linux_logo *logo;
+} fb_logo __read_mostly;
+
+static void fb_rotate_logo_ud(const u8 *in, u8 *out, u32 width, u32 height)
+{
+       u32 size = width * height, i;
+
+       out += size - 1;
+
+       for (i = size; i--; )
+               *out-- = *in++;
+}
+
+static void fb_rotate_logo_cw(const u8 *in, u8 *out, u32 width, u32 height)
+{
+       int i, j, h = height - 1;
+
+       for (i = 0; i < height; i++)
+               for (j = 0; j < width; j++)
+                               out[height * j + h - i] = *in++;
+}
+
+static void fb_rotate_logo_ccw(const u8 *in, u8 *out, u32 width, u32 height)
+{
+       int i, j, w = width - 1;
+
+       for (i = 0; i < height; i++)
+               for (j = 0; j < width; j++)
+                       out[height * (w - j) + i] = *in++;
+}
+
+static void fb_rotate_logo(struct fb_info *info, u8 *dst,
+                          struct fb_image *image, int rotate)
+{
+       u32 tmp;
+
+       if (rotate == FB_ROTATE_UD) {
+               fb_rotate_logo_ud(image->data, dst, image->width,
+                                 image->height);
+               image->dx = info->var.xres - image->width - image->dx;
+               image->dy = info->var.yres - image->height - image->dy;
+       } else if (rotate == FB_ROTATE_CW) {
+               fb_rotate_logo_cw(image->data, dst, image->width,
+                                 image->height);
+               tmp = image->width;
+               image->width = image->height;
+               image->height = tmp;
+               tmp = image->dy;
+               image->dy = image->dx;
+               image->dx = info->var.xres - image->width - tmp;
+       } else if (rotate == FB_ROTATE_CCW) {
+               fb_rotate_logo_ccw(image->data, dst, image->width,
+                                  image->height);
+               tmp = image->width;
+               image->width = image->height;
+               image->height = tmp;
+               tmp = image->dx;
+               image->dx = image->dy;
+               image->dy = info->var.yres - image->height - tmp;
+       }
+
+       image->data = dst;
+}
+
+static void fb_do_show_logo(struct fb_info *info, struct fb_image *image,
+                           int rotate, unsigned int num)
+{
+       unsigned int x;
+
+       if (rotate == FB_ROTATE_UR) {
+               for (x = 0;
+                    x < num && image->dx + image->width <= info->var.xres;
+                    x++) {
+                       info->fbops->fb_imageblit(info, image);
+                       image->dx += image->width + 8;
+               }
+       } else if (rotate == FB_ROTATE_UD) {
+               for (x = 0; x < num; x++) {
+                       info->fbops->fb_imageblit(info, image);
+                       image->dx -= image->width + 8;
+               }
+       } else if (rotate == FB_ROTATE_CW) {
+               for (x = 0;
+                    x < num && image->dy + image->height <= info->var.yres;
+                    x++) {
+                       info->fbops->fb_imageblit(info, image);
+                       image->dy += image->height + 8;
+               }
+       } else if (rotate == FB_ROTATE_CCW) {
+               for (x = 0; x < num; x++) {
+                       info->fbops->fb_imageblit(info, image);
+                       image->dy -= image->height + 8;
+               }
+       }
+}
+
+static int fb_show_logo_line(struct fb_info *info, int rotate,
+                            const struct linux_logo *logo, int y,
+                            unsigned int n)
+{
+       u32 *palette = NULL, *saved_pseudo_palette = NULL;
+       unsigned char *logo_new = NULL, *logo_rotate = NULL;
+       struct fb_image image;
+
+       /* Return if the frame buffer is not mapped or suspended */
+       if (logo == NULL || info->state != FBINFO_STATE_RUNNING ||
+           info->flags & FBINFO_MODULE)
+               return 0;
+
+       image.depth = 8;
+       image.data = logo->data;
+
+       if (fb_logo.needs_cmapreset)
+               fb_set_logocmap(info, logo);
+
+       if (fb_logo.needs_truepalette ||
+           fb_logo.needs_directpalette) {
+               palette = kmalloc(256 * 4, GFP_KERNEL);
+               if (palette == NULL)
+                       return 0;
+
+               if (fb_logo.needs_truepalette)
+                       fb_set_logo_truepalette(info, logo, palette);
+               else
+                       fb_set_logo_directpalette(info, logo, palette);
+
+               saved_pseudo_palette = info->pseudo_palette;
+               info->pseudo_palette = palette;
+       }
+
+       if (fb_logo.depth <= 4) {
+               logo_new = kmalloc(logo->width * logo->height, GFP_KERNEL);
+               if (logo_new == NULL) {
+                       kfree(palette);
+                       if (saved_pseudo_palette)
+                               info->pseudo_palette = saved_pseudo_palette;
+                       return 0;
+               }
+               image.data = logo_new;
+               fb_set_logo(info, logo, logo_new, fb_logo.depth);
+       }
+
+       image.dx = 0;
+       image.dy = y;
+       image.width = logo->width;
+       image.height = logo->height;
+
+       if (rotate) {
+               logo_rotate = kmalloc(logo->width *
+                                     logo->height, GFP_KERNEL);
+               if (logo_rotate)
+                       fb_rotate_logo(info, logo_rotate, &image, rotate);
+       }
+
+       fb_do_show_logo(info, &image, rotate, n);
+
+       kfree(palette);
+       if (saved_pseudo_palette != NULL)
+               info->pseudo_palette = saved_pseudo_palette;
+       kfree(logo_new);
+       kfree(logo_rotate);
+       return logo->height;
+}
+
+
+#ifdef CONFIG_FB_LOGO_EXTRA
+
+#define FB_LOGO_EX_NUM_MAX 10
+static struct logo_data_extra {
+       const struct linux_logo *logo;
+       unsigned int n;
+} fb_logo_ex[FB_LOGO_EX_NUM_MAX];
+static unsigned int fb_logo_ex_num;
+
+void fb_append_extra_logo(const struct linux_logo *logo, unsigned int n)
+{
+       if (!n || fb_logo_ex_num == FB_LOGO_EX_NUM_MAX)
+               return;
+
+       fb_logo_ex[fb_logo_ex_num].logo = logo;
+       fb_logo_ex[fb_logo_ex_num].n = n;
+       fb_logo_ex_num++;
+}
+
+static int fb_prepare_extra_logos(struct fb_info *info, unsigned int height,
+                                 unsigned int yres)
+{
+       unsigned int i;
+
+       /* FIXME: logo_ex supports only truecolor fb. */
+       if (info->fix.visual != FB_VISUAL_TRUECOLOR)
+               fb_logo_ex_num = 0;
+
+       for (i = 0; i < fb_logo_ex_num; i++) {
+               if (fb_logo_ex[i].logo->type != fb_logo.logo->type) {
+                       fb_logo_ex[i].logo = NULL;
+                       continue;
+               }
+               height += fb_logo_ex[i].logo->height;
+               if (height > yres) {
+                       height -= fb_logo_ex[i].logo->height;
+                       fb_logo_ex_num = i;
+                       break;
+               }
+       }
+       return height;
+}
+
+static int fb_show_extra_logos(struct fb_info *info, int y, int rotate)
+{
+       unsigned int i;
+
+       for (i = 0; i < fb_logo_ex_num; i++)
+               y += fb_show_logo_line(info, rotate,
+                                      fb_logo_ex[i].logo, y, fb_logo_ex[i].n);
+
+       return y;
+}
+
+#else /* !CONFIG_FB_LOGO_EXTRA */
+
+static inline int fb_prepare_extra_logos(struct fb_info *info,
+                                        unsigned int height,
+                                        unsigned int yres)
+{
+       return height;
+}
+
+static inline int fb_show_extra_logos(struct fb_info *info, int y, int rotate)
+{
+       return y;
+}
+
+#endif /* CONFIG_FB_LOGO_EXTRA */
+
+
+int fb_prepare_logo(struct fb_info *info, int rotate)
+{
+       int depth = fb_get_color_depth(&info->var, &info->fix);
+       unsigned int yres;
+
+       memset(&fb_logo, 0, sizeof(struct logo_data));
+
+       if (info->flags & FBINFO_MISC_TILEBLITTING ||
+           info->flags & FBINFO_MODULE)
+               return 0;
+
+       if (info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
+               depth = info->var.blue.length;
+               if (info->var.red.length < depth)
+                       depth = info->var.red.length;
+               if (info->var.green.length < depth)
+                       depth = info->var.green.length;
+       }
+
+       if (info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR && depth > 4) {
+               /* assume console colormap */
+               depth = 4;
+       }
+
+       /* Return if no suitable logo was found */
+       fb_logo.logo = fb_find_logo(depth);
+
+       if (!fb_logo.logo) {
+               return 0;
+       }
+
+       if (rotate == FB_ROTATE_UR || rotate == FB_ROTATE_UD)
+               yres = info->var.yres;
+       else
+               yres = info->var.xres;
+
+       if (fb_logo.logo->height > yres) {
+               fb_logo.logo = NULL;
+               return 0;
+       }
+
+       /* What depth we asked for might be different from what we get */
+       if (fb_logo.logo->type == LINUX_LOGO_CLUT224)
+               fb_logo.depth = 8;
+       else if (fb_logo.logo->type == LINUX_LOGO_VGA16)
+               fb_logo.depth = 4;
+       else
+               fb_logo.depth = 1;
+
+
+       if (fb_logo.depth > 4 && depth > 4) {
+               switch (info->fix.visual) {
+               case FB_VISUAL_TRUECOLOR:
+                       fb_logo.needs_truepalette = 1;
+                       break;
+               case FB_VISUAL_DIRECTCOLOR:
+                       fb_logo.needs_directpalette = 1;
+                       fb_logo.needs_cmapreset = 1;
+                       break;
+               case FB_VISUAL_PSEUDOCOLOR:
+                       fb_logo.needs_cmapreset = 1;
+                       break;
+               }
+       }
+
+       return fb_prepare_extra_logos(info, fb_logo.logo->height, yres);
+}
+
+int fb_show_logo(struct fb_info *info, int rotate)
+{
+       int y;
+
+       y = fb_show_logo_line(info, rotate, fb_logo.logo, 0,
+                             num_online_cpus());
+       y = fb_show_extra_logos(info, y, rotate);
+
+       return y;
+}
+#else
+int fb_prepare_logo(struct fb_info *info, int rotate) { return 0; }
+int fb_show_logo(struct fb_info *info, int rotate) { return 0; }
+#endif /* CONFIG_LOGO */
+EXPORT_SYMBOL(fb_prepare_logo);
+EXPORT_SYMBOL(fb_show_logo);
+
+static void *fb_seq_start(struct seq_file *m, loff_t *pos)
+{
+       mutex_lock(&registration_lock);
+       return (*pos < FB_MAX) ? pos : NULL;
+}
+
+static void *fb_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+       (*pos)++;
+       return (*pos < FB_MAX) ? pos : NULL;
+}
+
+static void fb_seq_stop(struct seq_file *m, void *v)
+{
+       mutex_unlock(&registration_lock);
+}
+
+static int fb_seq_show(struct seq_file *m, void *v)
+{
+       int i = *(loff_t *)v;
+       struct fb_info *fi = registered_fb[i];
+
+       if (fi)
+               seq_printf(m, "%d %s\n", fi->node, fi->fix.id);
+       return 0;
+}
+
+static const struct seq_operations proc_fb_seq_ops = {
+       .start  = fb_seq_start,
+       .next   = fb_seq_next,
+       .stop   = fb_seq_stop,
+       .show   = fb_seq_show,
+};
+
+static int proc_fb_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &proc_fb_seq_ops);
+}
+
+static const struct file_operations fb_proc_fops = {
+       .owner          = THIS_MODULE,
+       .open           = proc_fb_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
+
+/*
+ * We hold a reference to the fb_info in file->private_data,
+ * but if the current registered fb has changed, we don't
+ * actually want to use it.
+ *
+ * So look up the fb_info using the inode minor number,
+ * and just verify it against the reference we have.
+ */
+static struct fb_info *file_fb_info(struct file *file)
+{
+       struct inode *inode = file_inode(file);
+       int fbidx = iminor(inode);
+       struct fb_info *info = registered_fb[fbidx];
+
+       if (info != file->private_data)
+               info = NULL;
+       return info;
+}
+
+static ssize_t
+fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
+{
+       unsigned long p = *ppos;
+       struct fb_info *info = file_fb_info(file);
+       u8 *buffer, *dst;
+       u8 __iomem *src;
+       int c, cnt = 0, err = 0;
+       unsigned long total_size;
+
+       if (!info || ! info->screen_base)
+               return -ENODEV;
+
+       if (info->state != FBINFO_STATE_RUNNING)
+               return -EPERM;
+
+       if (info->fbops->fb_read)
+               return info->fbops->fb_read(info, buf, count, ppos);
+       
+       total_size = info->screen_size;
+
+       if (total_size == 0)
+               total_size = info->fix.smem_len;
+
+       if (p >= total_size)
+               return 0;
+
+       if (count >= total_size)
+               count = total_size;
+
+       if (count + p > total_size)
+               count = total_size - p;
+
+       buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count,
+                        GFP_KERNEL);
+       if (!buffer)
+               return -ENOMEM;
+
+       src = (u8 __iomem *) (info->screen_base + p);
+
+       if (info->fbops->fb_sync)
+               info->fbops->fb_sync(info);
+
+       while (count) {
+               c  = (count > PAGE_SIZE) ? PAGE_SIZE : count;
+               dst = buffer;
+               fb_memcpy_fromfb(dst, src, c);
+               dst += c;
+               src += c;
+
+               if (copy_to_user(buf, buffer, c)) {
+                       err = -EFAULT;
+                       break;
+               }
+               *ppos += c;
+               buf += c;
+               cnt += c;
+               count -= c;
+       }
+
+       kfree(buffer);
+
+       return (err) ? err : cnt;
+}
+
+static ssize_t
+fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
+{
+       unsigned long p = *ppos;
+       struct fb_info *info = file_fb_info(file);
+       u8 *buffer, *src;
+       u8 __iomem *dst;
+       int c, cnt = 0, err = 0;
+       unsigned long total_size;
+
+       if (!info || !info->screen_base)
+               return -ENODEV;
+
+       if (info->state != FBINFO_STATE_RUNNING)
+               return -EPERM;
+
+       if (info->fbops->fb_write)
+               return info->fbops->fb_write(info, buf, count, ppos);
+       
+       total_size = info->screen_size;
+
+       if (total_size == 0)
+               total_size = info->fix.smem_len;
+
+       if (p > total_size)
+               return -EFBIG;
+
+       if (count > total_size) {
+               err = -EFBIG;
+               count = total_size;
+       }
+
+       if (count + p > total_size) {
+               if (!err)
+                       err = -ENOSPC;
+
+               count = total_size - p;
+       }
+
+       buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count,
+                        GFP_KERNEL);
+       if (!buffer)
+               return -ENOMEM;
+
+       dst = (u8 __iomem *) (info->screen_base + p);
+
+       if (info->fbops->fb_sync)
+               info->fbops->fb_sync(info);
+
+       while (count) {
+               c = (count > PAGE_SIZE) ? PAGE_SIZE : count;
+               src = buffer;
+
+               if (copy_from_user(src, buf, c)) {
+                       err = -EFAULT;
+                       break;
+               }
+
+               fb_memcpy_tofb(dst, src, c);
+               dst += c;
+               src += c;
+               *ppos += c;
+               buf += c;
+               cnt += c;
+               count -= c;
+       }
+
+       kfree(buffer);
+
+       return (cnt) ? cnt : err;
+}
+
+int
+fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var)
+{
+       struct fb_fix_screeninfo *fix = &info->fix;
+       unsigned int yres = info->var.yres;
+       int err = 0;
+
+       if (var->yoffset > 0) {
+               if (var->vmode & FB_VMODE_YWRAP) {
+                       if (!fix->ywrapstep || (var->yoffset % fix->ywrapstep))
+                               err = -EINVAL;
+                       else
+                               yres = 0;
+               } else if (!fix->ypanstep || (var->yoffset % fix->ypanstep))
+                       err = -EINVAL;
+       }
+
+       if (var->xoffset > 0 && (!fix->xpanstep ||
+                                (var->xoffset % fix->xpanstep)))
+               err = -EINVAL;
+
+       if (err || !info->fbops->fb_pan_display ||
+           var->yoffset > info->var.yres_virtual - yres ||
+           var->xoffset > info->var.xres_virtual - info->var.xres)
+               return -EINVAL;
+
+       if ((err = info->fbops->fb_pan_display(var, info)))
+               return err;
+       info->var.xoffset = var->xoffset;
+       info->var.yoffset = var->yoffset;
+       if (var->vmode & FB_VMODE_YWRAP)
+               info->var.vmode |= FB_VMODE_YWRAP;
+       else
+               info->var.vmode &= ~FB_VMODE_YWRAP;
+       return 0;
+}
+EXPORT_SYMBOL(fb_pan_display);
+
+static int fb_check_caps(struct fb_info *info, struct fb_var_screeninfo *var,
+                        u32 activate)
+{
+       struct fb_event event;
+       struct fb_blit_caps caps, fbcaps;
+       int err = 0;
+
+       memset(&caps, 0, sizeof(caps));
+       memset(&fbcaps, 0, sizeof(fbcaps));
+       caps.flags = (activate & FB_ACTIVATE_ALL) ? 1 : 0;
+       event.info = info;
+       event.data = &caps;
+       fb_notifier_call_chain(FB_EVENT_GET_REQ, &event);
+       info->fbops->fb_get_caps(info, &fbcaps, var);
+
+       if (((fbcaps.x ^ caps.x) & caps.x) ||
+           ((fbcaps.y ^ caps.y) & caps.y) ||
+           (fbcaps.len < caps.len))
+               err = -EINVAL;
+
+       return err;
+}
+
+int
+fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
+{
+       int flags = info->flags;
+       int ret = 0;
+
+       if (var->activate & FB_ACTIVATE_INV_MODE) {
+               struct fb_videomode mode1, mode2;
+
+               fb_var_to_videomode(&mode1, var);
+               fb_var_to_videomode(&mode2, &info->var);
+               /* make sure we don't delete the videomode of current var */
+               ret = fb_mode_is_equal(&mode1, &mode2);
+
+               if (!ret) {
+                   struct fb_event event;
+
+                   event.info = info;
+                   event.data = &mode1;
+                   ret = fb_notifier_call_chain(FB_EVENT_MODE_DELETE, &event);
+               }
+
+               if (!ret)
+                   fb_delete_videomode(&mode1, &info->modelist);
+
+
+               ret = (ret) ? -EINVAL : 0;
+               goto done;
+       }
+
+       if ((var->activate & FB_ACTIVATE_FORCE) ||
+           memcmp(&info->var, var, sizeof(struct fb_var_screeninfo))) {
+               u32 activate = var->activate;
+
+               /* When using FOURCC mode, make sure the red, green, blue and
+                * transp fields are set to 0.
+                */
+               if ((info->fix.capabilities & FB_CAP_FOURCC) &&
+                   var->grayscale > 1) {
+                       if (var->red.offset     || var->green.offset    ||
+                           var->blue.offset    || var->transp.offset   ||
+                           var->red.length     || var->green.length    ||
+                           var->blue.length    || var->transp.length   ||
+                           var->red.msb_right  || var->green.msb_right ||
+                           var->blue.msb_right || var->transp.msb_right)
+                               return -EINVAL;
+               }
+
+               if (!info->fbops->fb_check_var) {
+                       *var = info->var;
+                       goto done;
+               }
+
+               ret = info->fbops->fb_check_var(var, info);
+
+               if (ret)
+                       goto done;
+
+               if ((var->activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) {
+                       struct fb_var_screeninfo old_var;
+                       struct fb_videomode mode;
+
+                       if (info->fbops->fb_get_caps) {
+                               ret = fb_check_caps(info, var, activate);
+
+                               if (ret)
+                                       goto done;
+                       }
+
+                       old_var = info->var;
+                       info->var = *var;
+
+                       if (info->fbops->fb_set_par) {
+                               ret = info->fbops->fb_set_par(info);
+
+                               if (ret) {
+                                       info->var = old_var;
+                                       printk(KERN_WARNING "detected "
+                                               "fb_set_par error, "
+                                               "error code: %d\n", ret);
+                                       goto done;
+                               }
+                       }
+
+                       fb_pan_display(info, &info->var);
+                       fb_set_cmap(&info->cmap, info);
+                       fb_var_to_videomode(&mode, &info->var);
+
+                       if (info->modelist.prev && info->modelist.next &&
+                           !list_empty(&info->modelist))
+                               ret = fb_add_videomode(&mode, &info->modelist);
+
+                       if (!ret && (flags & FBINFO_MISC_USEREVENT)) {
+                               struct fb_event event;
+                               int evnt = (activate & FB_ACTIVATE_ALL) ?
+                                       FB_EVENT_MODE_CHANGE_ALL :
+                                       FB_EVENT_MODE_CHANGE;
+
+                               info->flags &= ~FBINFO_MISC_USEREVENT;
+                               event.info = info;
+                               event.data = &mode;
+                               fb_notifier_call_chain(evnt, &event);
+                       }
+               }
+       }
+
+ done:
+       return ret;
+}
+EXPORT_SYMBOL(fb_set_var);
+
+int
+fb_blank(struct fb_info *info, int blank)
+{      
+       struct fb_event event;
+       int ret = -EINVAL, early_ret;
+
+       if (blank > FB_BLANK_POWERDOWN)
+               blank = FB_BLANK_POWERDOWN;
+
+       event.info = info;
+       event.data = &blank;
+
+       early_ret = fb_notifier_call_chain(FB_EARLY_EVENT_BLANK, &event);
+
+       if (info->fbops->fb_blank)
+               ret = info->fbops->fb_blank(blank, info);
+
+       if (!ret)
+               fb_notifier_call_chain(FB_EVENT_BLANK, &event);
+       else {
+               /*
+                * if fb_blank is failed then revert effects of
+                * the early blank event.
+                */
+               if (!early_ret)
+                       fb_notifier_call_chain(FB_R_EARLY_EVENT_BLANK, &event);
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL(fb_blank);
+
+static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
+                       unsigned long arg)
+{
+       struct fb_ops *fb;
+       struct fb_var_screeninfo var;
+       struct fb_fix_screeninfo fix;
+       struct fb_con2fbmap con2fb;
+       struct fb_cmap cmap_from;
+       struct fb_cmap_user cmap;
+       struct fb_event event;
+       void __user *argp = (void __user *)arg;
+       long ret = 0;
+
+       switch (cmd) {
+       case FBIOGET_VSCREENINFO:
+               if (!lock_fb_info(info))
+                       return -ENODEV;
+               var = info->var;
+               unlock_fb_info(info);
+
+               ret = copy_to_user(argp, &var, sizeof(var)) ? -EFAULT : 0;
+               break;
+       case FBIOPUT_VSCREENINFO:
+               if (copy_from_user(&var, argp, sizeof(var)))
+                       return -EFAULT;
+               console_lock();
+               if (!lock_fb_info(info)) {
+                       console_unlock();
+                       return -ENODEV;
+               }
+               info->flags |= FBINFO_MISC_USEREVENT;
+               ret = fb_set_var(info, &var);
+               info->flags &= ~FBINFO_MISC_USEREVENT;
+               unlock_fb_info(info);
+               console_unlock();
+               if (!ret && copy_to_user(argp, &var, sizeof(var)))
+                       ret = -EFAULT;
+               break;
+       case FBIOGET_FSCREENINFO:
+               if (!lock_fb_info(info))
+                       return -ENODEV;
+               fix = info->fix;
+               unlock_fb_info(info);
+
+               ret = copy_to_user(argp, &fix, sizeof(fix)) ? -EFAULT : 0;
+               break;
+       case FBIOPUTCMAP:
+               if (copy_from_user(&cmap, argp, sizeof(cmap)))
+                       return -EFAULT;
+               ret = fb_set_user_cmap(&cmap, info);
+               break;
+       case FBIOGETCMAP:
+               if (copy_from_user(&cmap, argp, sizeof(cmap)))
+                       return -EFAULT;
+               if (!lock_fb_info(info))
+                       return -ENODEV;
+               cmap_from = info->cmap;
+               unlock_fb_info(info);
+               ret = fb_cmap_to_user(&cmap_from, &cmap);
+               break;
+       case FBIOPAN_DISPLAY:
+               if (copy_from_user(&var, argp, sizeof(var)))
+                       return -EFAULT;
+               console_lock();
+               if (!lock_fb_info(info)) {
+                       console_unlock();
+                       return -ENODEV;
+               }
+               ret = fb_pan_display(info, &var);
+               unlock_fb_info(info);
+               console_unlock();
+               if (ret == 0 && copy_to_user(argp, &var, sizeof(var)))
+                       return -EFAULT;
+               break;
+       case FBIO_CURSOR:
+               ret = -EINVAL;
+               break;
+       case FBIOGET_CON2FBMAP:
+               if (copy_from_user(&con2fb, argp, sizeof(con2fb)))
+                       return -EFAULT;
+               if (con2fb.console < 1 || con2fb.console > MAX_NR_CONSOLES)
+                       return -EINVAL;
+               con2fb.framebuffer = -1;
+               event.data = &con2fb;
+               if (!lock_fb_info(info))
+                       return -ENODEV;
+               event.info = info;
+               fb_notifier_call_chain(FB_EVENT_GET_CONSOLE_MAP, &event);
+               unlock_fb_info(info);
+               ret = copy_to_user(argp, &con2fb, sizeof(con2fb)) ? -EFAULT : 0;
+               break;
+       case FBIOPUT_CON2FBMAP:
+               if (copy_from_user(&con2fb, argp, sizeof(con2fb)))
+                       return -EFAULT;
+               if (con2fb.console < 1 || con2fb.console > MAX_NR_CONSOLES)
+                       return -EINVAL;
+               if (con2fb.framebuffer >= FB_MAX)
+                       return -EINVAL;
+               if (!registered_fb[con2fb.framebuffer])
+                       request_module("fb%d", con2fb.framebuffer);
+               if (!registered_fb[con2fb.framebuffer]) {
+                       ret = -EINVAL;
+                       break;
+               }
+               event.data = &con2fb;
+               console_lock();
+               if (!lock_fb_info(info)) {
+                       console_unlock();
+                       return -ENODEV;
+               }
+               event.info = info;
+               ret = fb_notifier_call_chain(FB_EVENT_SET_CONSOLE_MAP, &event);
+               unlock_fb_info(info);
+               console_unlock();
+               break;
+       case FBIOBLANK:
+               console_lock();
+               if (!lock_fb_info(info)) {
+                       console_unlock();
+                       return -ENODEV;
+               }
+               info->flags |= FBINFO_MISC_USEREVENT;
+               ret = fb_blank(info, arg);
+               info->flags &= ~FBINFO_MISC_USEREVENT;
+               unlock_fb_info(info);
+               console_unlock();
+               break;
+       default:
+               if (!lock_fb_info(info))
+                       return -ENODEV;
+               fb = info->fbops;
+               if (fb->fb_ioctl)
+                       ret = fb->fb_ioctl(info, cmd, arg);
+               else
+                       ret = -ENOTTY;
+               unlock_fb_info(info);
+       }
+       return ret;
+}
+
+static long fb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+       struct fb_info *info = file_fb_info(file);
+
+       if (!info)
+               return -ENODEV;
+       return do_fb_ioctl(info, cmd, arg);
+}
+
+#ifdef CONFIG_COMPAT
+struct fb_fix_screeninfo32 {
+       char                    id[16];
+       compat_caddr_t          smem_start;
+       u32                     smem_len;
+       u32                     type;
+       u32                     type_aux;
+       u32                     visual;
+       u16                     xpanstep;
+       u16                     ypanstep;
+       u16                     ywrapstep;
+       u32                     line_length;
+       compat_caddr_t          mmio_start;
+       u32                     mmio_len;
+       u32                     accel;
+       u16                     reserved[3];
+};
+
+struct fb_cmap32 {
+       u32                     start;
+       u32                     len;
+       compat_caddr_t  red;
+       compat_caddr_t  green;
+       compat_caddr_t  blue;
+       compat_caddr_t  transp;
+};
+
+static int fb_getput_cmap(struct fb_info *info, unsigned int cmd,
+                         unsigned long arg)
+{
+       struct fb_cmap_user __user *cmap;
+       struct fb_cmap32 __user *cmap32;
+       __u32 data;
+       int err;
+
+       cmap = compat_alloc_user_space(sizeof(*cmap));
+       cmap32 = compat_ptr(arg);
+
+       if (copy_in_user(&cmap->start, &cmap32->start, 2 * sizeof(__u32)))
+               return -EFAULT;
+
+       if (get_user(data, &cmap32->red) ||
+           put_user(compat_ptr(data), &cmap->red) ||
+           get_user(data, &cmap32->green) ||
+           put_user(compat_ptr(data), &cmap->green) ||
+           get_user(data, &cmap32->blue) ||
+           put_user(compat_ptr(data), &cmap->blue) ||
+           get_user(data, &cmap32->transp) ||
+           put_user(compat_ptr(data), &cmap->transp))
+               return -EFAULT;
+
+       err = do_fb_ioctl(info, cmd, (unsigned long) cmap);
+
+       if (!err) {
+               if (copy_in_user(&cmap32->start,
+                                &cmap->start,
+                                2 * sizeof(__u32)))
+                       err = -EFAULT;
+       }
+       return err;
+}
+
+static int do_fscreeninfo_to_user(struct fb_fix_screeninfo *fix,
+                                 struct fb_fix_screeninfo32 __user *fix32)
+{
+       __u32 data;
+       int err;
+
+       err = copy_to_user(&fix32->id, &fix->id, sizeof(fix32->id));
+
+       data = (__u32) (unsigned long) fix->smem_start;
+       err |= put_user(data, &fix32->smem_start);
+
+       err |= put_user(fix->smem_len, &fix32->smem_len);
+       err |= put_user(fix->type, &fix32->type);
+       err |= put_user(fix->type_aux, &fix32->type_aux);
+       err |= put_user(fix->visual, &fix32->visual);
+       err |= put_user(fix->xpanstep, &fix32->xpanstep);
+       err |= put_user(fix->ypanstep, &fix32->ypanstep);
+       err |= put_user(fix->ywrapstep, &fix32->ywrapstep);
+       err |= put_user(fix->line_length, &fix32->line_length);
+
+       data = (__u32) (unsigned long) fix->mmio_start;
+       err |= put_user(data, &fix32->mmio_start);
+
+       err |= put_user(fix->mmio_len, &fix32->mmio_len);
+       err |= put_user(fix->accel, &fix32->accel);
+       err |= copy_to_user(fix32->reserved, fix->reserved,
+                           sizeof(fix->reserved));
+
+       if (err)
+               return -EFAULT;
+       return 0;
+}
+
+static int fb_get_fscreeninfo(struct fb_info *info, unsigned int cmd,
+                             unsigned long arg)
+{
+       mm_segment_t old_fs;
+       struct fb_fix_screeninfo fix;
+       struct fb_fix_screeninfo32 __user *fix32;
+       int err;
+
+       fix32 = compat_ptr(arg);
+
+       old_fs = get_fs();
+       set_fs(KERNEL_DS);
+       err = do_fb_ioctl(info, cmd, (unsigned long) &fix);
+       set_fs(old_fs);
+
+       if (!err)
+               err = do_fscreeninfo_to_user(&fix, fix32);
+
+       return err;
+}
+
+static long fb_compat_ioctl(struct file *file, unsigned int cmd,
+                           unsigned long arg)
+{
+       struct fb_info *info = file_fb_info(file);
+       struct fb_ops *fb;
+       long ret = -ENOIOCTLCMD;
+
+       if (!info)
+               return -ENODEV;
+       fb = info->fbops;
+       switch(cmd) {
+       case FBIOGET_VSCREENINFO:
+       case FBIOPUT_VSCREENINFO:
+       case FBIOPAN_DISPLAY:
+       case FBIOGET_CON2FBMAP:
+       case FBIOPUT_CON2FBMAP:
+               arg = (unsigned long) compat_ptr(arg);
+       case FBIOBLANK:
+               ret = do_fb_ioctl(info, cmd, arg);
+               break;
+
+       case FBIOGET_FSCREENINFO:
+               ret = fb_get_fscreeninfo(info, cmd, arg);
+               break;
+
+       case FBIOGETCMAP:
+       case FBIOPUTCMAP:
+               ret = fb_getput_cmap(info, cmd, arg);
+               break;
+
+       default:
+               if (fb->fb_compat_ioctl)
+                       ret = fb->fb_compat_ioctl(info, cmd, arg);
+               break;
+       }
+       return ret;
+}
+#endif
+
+static int
+fb_mmap(struct file *file, struct vm_area_struct * vma)
+{
+       struct fb_info *info = file_fb_info(file);
+       struct fb_ops *fb;
+       unsigned long mmio_pgoff;
+       unsigned long start;
+       u32 len;
+
+       if (!info)
+               return -ENODEV;
+       fb = info->fbops;
+       if (!fb)
+               return -ENODEV;
+       mutex_lock(&info->mm_lock);
+       if (fb->fb_mmap) {
+               int res;
+               res = fb->fb_mmap(info, vma);
+               mutex_unlock(&info->mm_lock);
+               return res;
+       }
+
+       /*
+        * Ugh. This can be either the frame buffer mapping, or
+        * if pgoff points past it, the mmio mapping.
+        */
+       start = info->fix.smem_start;
+       len = info->fix.smem_len;
+       mmio_pgoff = PAGE_ALIGN((start & ~PAGE_MASK) + len) >> PAGE_SHIFT;
+       if (vma->vm_pgoff >= mmio_pgoff) {
+               if (info->var.accel_flags) {
+                       mutex_unlock(&info->mm_lock);
+                       return -EINVAL;
+               }
+
+               vma->vm_pgoff -= mmio_pgoff;
+               start = info->fix.mmio_start;
+               len = info->fix.mmio_len;
+       }
+       mutex_unlock(&info->mm_lock);
+
+       vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+       fb_pgprotect(file, vma, start);
+
+       return vm_iomap_memory(vma, start, len);
+}
+
+static int
+fb_open(struct inode *inode, struct file *file)
+__acquires(&info->lock)
+__releases(&info->lock)
+{
+       int fbidx = iminor(inode);
+       struct fb_info *info;
+       int res = 0;
+
+       info = get_fb_info(fbidx);
+       if (!info) {
+               request_module("fb%d", fbidx);
+               info = get_fb_info(fbidx);
+               if (!info)
+                       return -ENODEV;
+       }
+       if (IS_ERR(info))
+               return PTR_ERR(info);
+
+       mutex_lock(&info->lock);
+       if (!try_module_get(info->fbops->owner)) {
+               res = -ENODEV;
+               goto out;
+       }
+       file->private_data = info;
+       if (info->fbops->fb_open) {
+               res = info->fbops->fb_open(info,1);
+               if (res)
+                       module_put(info->fbops->owner);
+       }
+#ifdef CONFIG_FB_DEFERRED_IO
+       if (info->fbdefio)
+               fb_deferred_io_open(info, inode, file);
+#endif
+out:
+       mutex_unlock(&info->lock);
+       if (res)
+               put_fb_info(info);
+       return res;
+}
+
+static int 
+fb_release(struct inode *inode, struct file *file)
+__acquires(&info->lock)
+__releases(&info->lock)
+{
+       struct fb_info * const info = file->private_data;
+
+       mutex_lock(&info->lock);
+       if (info->fbops->fb_release)
+               info->fbops->fb_release(info,1);
+       module_put(info->fbops->owner);
+       mutex_unlock(&info->lock);
+       put_fb_info(info);
+       return 0;
+}
+
+static const struct file_operations fb_fops = {
+       .owner =        THIS_MODULE,
+       .read =         fb_read,
+       .write =        fb_write,
+       .unlocked_ioctl = fb_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl = fb_compat_ioctl,
+#endif
+       .mmap =         fb_mmap,
+       .open =         fb_open,
+       .release =      fb_release,
+#ifdef HAVE_ARCH_FB_UNMAPPED_AREA
+       .get_unmapped_area = get_fb_unmapped_area,
+#endif
+#ifdef CONFIG_FB_DEFERRED_IO
+       .fsync =        fb_deferred_io_fsync,
+#endif
+       .llseek =       default_llseek,
+};
+
+struct class *fb_class;
+EXPORT_SYMBOL(fb_class);
+
+static int fb_check_foreignness(struct fb_info *fi)
+{
+       const bool foreign_endian = fi->flags & FBINFO_FOREIGN_ENDIAN;
+
+       fi->flags &= ~FBINFO_FOREIGN_ENDIAN;
+
+#ifdef __BIG_ENDIAN
+       fi->flags |= foreign_endian ? 0 : FBINFO_BE_MATH;
+#else
+       fi->flags |= foreign_endian ? FBINFO_BE_MATH : 0;
+#endif /* __BIG_ENDIAN */
+
+       if (fi->flags & FBINFO_BE_MATH && !fb_be_math(fi)) {
+               pr_err("%s: enable CONFIG_FB_BIG_ENDIAN to "
+                      "support this framebuffer\n", fi->fix.id);
+               return -ENOSYS;
+       } else if (!(fi->flags & FBINFO_BE_MATH) && fb_be_math(fi)) {
+               pr_err("%s: enable CONFIG_FB_LITTLE_ENDIAN to "
+                      "support this framebuffer\n", fi->fix.id);
+               return -ENOSYS;
+       }
+
+       return 0;
+}
+
+static bool apertures_overlap(struct aperture *gen, struct aperture *hw)
+{
+       /* is the generic aperture base the same as the HW one */
+       if (gen->base == hw->base)
+               return true;
+       /* is the generic aperture base inside the hw base->hw base+size */
+       if (gen->base > hw->base && gen->base < hw->base + hw->size)
+               return true;
+       return false;
+}
+
+static bool fb_do_apertures_overlap(struct apertures_struct *gena,
+                                   struct apertures_struct *hwa)
+{
+       int i, j;
+       if (!hwa || !gena)
+               return false;
+
+       for (i = 0; i < hwa->count; ++i) {
+               struct aperture *h = &hwa->ranges[i];
+               for (j = 0; j < gena->count; ++j) {
+                       struct aperture *g = &gena->ranges[j];
+                       printk(KERN_DEBUG "checking generic (%llx %llx) vs hw (%llx %llx)\n",
+                               (unsigned long long)g->base,
+                               (unsigned long long)g->size,
+                               (unsigned long long)h->base,
+                               (unsigned long long)h->size);
+                       if (apertures_overlap(g, h))
+                               return true;
+               }
+       }
+
+       return false;
+}
+
+static int do_unregister_framebuffer(struct fb_info *fb_info);
+
+#define VGA_FB_PHYS 0xA0000
+static int do_remove_conflicting_framebuffers(struct apertures_struct *a,
+                                             const char *name, bool primary)
+{
+       int i, ret;
+
+       /* check all firmware fbs and kick off if the base addr overlaps */
+       for (i = 0 ; i < FB_MAX; i++) {
+               struct apertures_struct *gen_aper;
+               if (!registered_fb[i])
+                       continue;
+
+               if (!(registered_fb[i]->flags & FBINFO_MISC_FIRMWARE))
+                       continue;
+
+               gen_aper = registered_fb[i]->apertures;
+               if (fb_do_apertures_overlap(gen_aper, a) ||
+                       (primary && gen_aper && gen_aper->count &&
+                        gen_aper->ranges[0].base == VGA_FB_PHYS)) {
+
+                       printk(KERN_INFO "fb: switching to %s from %s\n",
+                              name, registered_fb[i]->fix.id);
+                       ret = do_unregister_framebuffer(registered_fb[i]);
+                       if (ret)
+                               return ret;
+               }
+       }
+
+       return 0;
+}
+
+static int do_register_framebuffer(struct fb_info *fb_info)
+{
+       int i, ret;
+       struct fb_event event;
+       struct fb_videomode mode;
+
+       if (fb_check_foreignness(fb_info))
+               return -ENOSYS;
+
+       ret = do_remove_conflicting_framebuffers(fb_info->apertures,
+                                                fb_info->fix.id,
+                                                fb_is_primary_device(fb_info));
+       if (ret)
+               return ret;
+
+       if (num_registered_fb == FB_MAX)
+               return -ENXIO;
+
+       num_registered_fb++;
+       for (i = 0 ; i < FB_MAX; i++)
+               if (!registered_fb[i])
+                       break;
+       fb_info->node = i;
+       atomic_set(&fb_info->count, 1);
+       mutex_init(&fb_info->lock);
+       mutex_init(&fb_info->mm_lock);
+
+       fb_info->dev = device_create(fb_class, fb_info->device,
+                                    MKDEV(FB_MAJOR, i), NULL, "fb%d", i);
+       if (IS_ERR(fb_info->dev)) {
+               /* Not fatal */
+               printk(KERN_WARNING "Unable to create device for framebuffer %d; errno = %ld\n", i, PTR_ERR(fb_info->dev));
+               fb_info->dev = NULL;
+       } else
+               fb_init_device(fb_info);
+
+       if (fb_info->pixmap.addr == NULL) {
+               fb_info->pixmap.addr = kmalloc(FBPIXMAPSIZE, GFP_KERNEL);
+               if (fb_info->pixmap.addr) {
+                       fb_info->pixmap.size = FBPIXMAPSIZE;
+                       fb_info->pixmap.buf_align = 1;
+                       fb_info->pixmap.scan_align = 1;
+                       fb_info->pixmap.access_align = 32;
+                       fb_info->pixmap.flags = FB_PIXMAP_DEFAULT;
+               }
+       }       
+       fb_info->pixmap.offset = 0;
+
+       if (!fb_info->pixmap.blit_x)
+               fb_info->pixmap.blit_x = ~(u32)0;
+
+       if (!fb_info->pixmap.blit_y)
+               fb_info->pixmap.blit_y = ~(u32)0;
+
+       if (!fb_info->modelist.prev || !fb_info->modelist.next)
+               INIT_LIST_HEAD(&fb_info->modelist);
+
+       if (fb_info->skip_vt_switch)
+               pm_vt_switch_required(fb_info->dev, false);
+       else
+               pm_vt_switch_required(fb_info->dev, true);
+
+       fb_var_to_videomode(&mode, &fb_info->var);
+       fb_add_videomode(&mode, &fb_info->modelist);
+       registered_fb[i] = fb_info;
+
+       event.info = fb_info;
+       console_lock();
+       if (!lock_fb_info(fb_info)) {
+               console_unlock();
+               return -ENODEV;
+       }
+
+       fb_notifier_call_chain(FB_EVENT_FB_REGISTERED, &event);
+       unlock_fb_info(fb_info);
+       console_unlock();
+       return 0;
+}
+
+static int do_unregister_framebuffer(struct fb_info *fb_info)
+{
+       struct fb_event event;
+       int i, ret = 0;
+
+       i = fb_info->node;
+       if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
+               return -EINVAL;
+
+       console_lock();
+       if (!lock_fb_info(fb_info)) {
+               console_unlock();
+               return -ENODEV;
+       }
+
+       event.info = fb_info;
+       ret = fb_notifier_call_chain(FB_EVENT_FB_UNBIND, &event);
+       unlock_fb_info(fb_info);
+       console_unlock();
+
+       if (ret)
+               return -EINVAL;
+
+       pm_vt_switch_unregister(fb_info->dev);
+
+       unlink_framebuffer(fb_info);
+       if (fb_info->pixmap.addr &&
+           (fb_info->pixmap.flags & FB_PIXMAP_DEFAULT))
+               kfree(fb_info->pixmap.addr);
+       fb_destroy_modelist(&fb_info->modelist);
+       registered_fb[i] = NULL;
+       num_registered_fb--;
+       fb_cleanup_device(fb_info);
+       event.info = fb_info;
+       console_lock();
+       fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event);
+       console_unlock();
+
+       /* this may free fb info */
+       put_fb_info(fb_info);
+       return 0;
+}
+
+int unlink_framebuffer(struct fb_info *fb_info)
+{
+       int i;
+
+       i = fb_info->node;
+       if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
+               return -EINVAL;
+
+       if (fb_info->dev) {
+               device_destroy(fb_class, MKDEV(FB_MAJOR, i));
+               fb_info->dev = NULL;
+       }
+       return 0;
+}
+EXPORT_SYMBOL(unlink_framebuffer);
+
+int remove_conflicting_framebuffers(struct apertures_struct *a,
+                                   const char *name, bool primary)
+{
+       int ret;
+
+       mutex_lock(&registration_lock);
+       ret = do_remove_conflicting_framebuffers(a, name, primary);
+       mutex_unlock(&registration_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL(remove_conflicting_framebuffers);
+
+/**
+ *     register_framebuffer - registers a frame buffer device
+ *     @fb_info: frame buffer info structure
+ *
+ *     Registers a frame buffer device @fb_info.
+ *
+ *     Returns negative errno on error, or zero for success.
+ *
+ */
+int
+register_framebuffer(struct fb_info *fb_info)
+{
+       int ret;
+
+       mutex_lock(&registration_lock);
+       ret = do_register_framebuffer(fb_info);
+       mutex_unlock(&registration_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL(register_framebuffer);
+
+/**
+ *     unregister_framebuffer - releases a frame buffer device
+ *     @fb_info: frame buffer info structure
+ *
+ *     Unregisters a frame buffer device @fb_info.
+ *
+ *     Returns negative errno on error, or zero for success.
+ *
+ *      This function will also notify the framebuffer console
+ *      to release the driver.
+ *
+ *      This is meant to be called within a driver's module_exit()
+ *      function. If this is called outside module_exit(), ensure
+ *      that the driver implements fb_open() and fb_release() to
+ *      check that no processes are using the device.
+ */
+int
+unregister_framebuffer(struct fb_info *fb_info)
+{
+       int ret;
+
+       mutex_lock(&registration_lock);
+       ret = do_unregister_framebuffer(fb_info);
+       mutex_unlock(&registration_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL(unregister_framebuffer);
+
+/**
+ *     fb_set_suspend - low level driver signals suspend
+ *     @info: framebuffer affected
+ *     @state: 0 = resuming, !=0 = suspending
+ *
+ *     This is meant to be used by low level drivers to
+ *     signal suspend/resume to the core & clients.
+ *     It must be called with the console semaphore held
+ */
+void fb_set_suspend(struct fb_info *info, int state)
+{
+       struct fb_event event;
+
+       event.info = info;
+       if (state) {
+               fb_notifier_call_chain(FB_EVENT_SUSPEND, &event);
+               info->state = FBINFO_STATE_SUSPENDED;
+       } else {
+               info->state = FBINFO_STATE_RUNNING;
+               fb_notifier_call_chain(FB_EVENT_RESUME, &event);
+       }
+}
+EXPORT_SYMBOL(fb_set_suspend);
+
+/**
+ *     fbmem_init - init frame buffer subsystem
+ *
+ *     Initialize the frame buffer subsystem.
+ *
+ *     NOTE: This function is _only_ to be called by drivers/char/mem.c.
+ *
+ */
+
+static int __init
+fbmem_init(void)
+{
+       proc_create("fb", 0, NULL, &fb_proc_fops);
+
+       if (register_chrdev(FB_MAJOR,"fb",&fb_fops))
+               printk("unable to get major %d for fb devs\n", FB_MAJOR);
+
+       fb_class = class_create(THIS_MODULE, "graphics");
+       if (IS_ERR(fb_class)) {
+               printk(KERN_WARNING "Unable to create fb class; errno = %ld\n", PTR_ERR(fb_class));
+               fb_class = NULL;
+       }
+       return 0;
+}
+
+#ifdef MODULE
+module_init(fbmem_init);
+static void __exit
+fbmem_exit(void)
+{
+       remove_proc_entry("fb", NULL);
+       class_destroy(fb_class);
+       unregister_chrdev(FB_MAJOR, "fb");
+}
+
+module_exit(fbmem_exit);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Framebuffer base");
+#else
+subsys_initcall(fbmem_init);
+#endif
+
+int fb_new_modelist(struct fb_info *info)
+{
+       struct fb_event event;
+       struct fb_var_screeninfo var = info->var;
+       struct list_head *pos, *n;
+       struct fb_modelist *modelist;
+       struct fb_videomode *m, mode;
+       int err = 1;
+
+       list_for_each_safe(pos, n, &info->modelist) {
+               modelist = list_entry(pos, struct fb_modelist, list);
+               m = &modelist->mode;
+               fb_videomode_to_var(&var, m);
+               var.activate = FB_ACTIVATE_TEST;
+               err = fb_set_var(info, &var);
+               fb_var_to_videomode(&mode, &var);
+               if (err || !fb_mode_is_equal(m, &mode)) {
+                       list_del(pos);
+                       kfree(pos);
+               }
+       }
+
+       err = 1;
+
+       if (!list_empty(&info->modelist)) {
+               event.info = info;
+               err = fb_notifier_call_chain(FB_EVENT_NEW_MODELIST, &event);
+       }
+
+       return err;
+}
+
+MODULE_LICENSE("GPL");