Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 1037 insertions, 0 deletions

diff --git a/kernel/drivers/video/fbdev/skeletonfb.c b/kernel/drivers/video/fbdev/skeletonfb.c
new file mode 100644
index 000000000..fefde7c6a
--- /dev/null
+++ b/kernel/drivers/video/fbdev/skeletonfb.c
@@ -0,0 +1,1037 @@
+/*
+ * linux/drivers/video/skeletonfb.c -- Skeleton for a frame buffer device
+ *
+ *  Modified to new api Jan 2001 by James Simmons (jsimmons@transvirtual.com)
+ *
+ *  Created 28 Dec 1997 by Geert Uytterhoeven
+ *
+ *
+ *  I have started rewriting this driver as a example of the upcoming new API
+ *  The primary goal is to remove the console code from fbdev and place it
+ *  into fbcon.c. This reduces the code and makes writing a new fbdev driver
+ *  easy since the author doesn't need to worry about console internals. It
+ *  also allows the ability to run fbdev without a console/tty system on top 
+ *  of it. 
+ *
+ *  First the roles of struct fb_info and struct display have changed. Struct
+ *  display will go away. The way the new framebuffer console code will
+ *  work is that it will act to translate data about the tty/console in 
+ *  struct vc_data to data in a device independent way in struct fb_info. Then
+ *  various functions in struct fb_ops will be called to store the device 
+ *  dependent state in the par field in struct fb_info and to change the 
+ *  hardware to that state. This allows a very clean separation of the fbdev
+ *  layer from the console layer. It also allows one to use fbdev on its own
+ *  which is a bounus for embedded devices. The reason this approach works is  
+ *  for each framebuffer device when used as a tty/console device is allocated
+ *  a set of virtual terminals to it. Only one virtual terminal can be active 
+ *  per framebuffer device. We already have all the data we need in struct 
+ *  vc_data so why store a bunch of colormaps and other fbdev specific data
+ *  per virtual terminal. 
+ *
+ *  As you can see doing this makes the con parameter pretty much useless
+ *  for struct fb_ops functions, as it should be. Also having struct  
+ *  fb_var_screeninfo and other data in fb_info pretty much eliminates the 
+ *  need for get_fix and get_var. Once all drivers use the fix, var, and cmap
+ *  fbcon can be written around these fields. This will also eliminate the
+ *  need to regenerate struct fb_var_screeninfo, struct fb_fix_screeninfo
+ *  struct fb_cmap every time get_var, get_fix, get_cmap functions are called
+ *  as many drivers do now. 
+ *
+ *  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/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+
+    /*
+     *  This is just simple sample code.
+     *
+     *  No warranty that it actually compiles.
+     *  Even less warranty that it actually works :-)
+     */
+
+/*
+ * Driver data
+ */
+static char *mode_option;
+
+/*
+ *  If your driver supports multiple boards, you should make the  
+ *  below data types arrays, or allocate them dynamically (using kmalloc()). 
+ */ 
+
+/* 
+ * This structure defines the hardware state of the graphics card. Normally
+ * you place this in a header file in linux/include/video. This file usually
+ * also includes register information. That allows other driver subsystems
+ * and userland applications the ability to use the same header file to 
+ * avoid duplicate work and easy porting of software. 
+ */
+struct xxx_par;
+
+/*
+ * Here we define the default structs fb_fix_screeninfo and fb_var_screeninfo
+ * if we don't use modedb. If we do use modedb see xxxfb_init how to use it
+ * to get a fb_var_screeninfo. Otherwise define a default var as well. 
+ */
+static struct fb_fix_screeninfo xxxfb_fix = {
+	.id =		"FB's name", 
+	.type =		FB_TYPE_PACKED_PIXELS,
+	.visual =	FB_VISUAL_PSEUDOCOLOR,
+	.xpanstep =	1,
+	.ypanstep =	1,
+	.ywrapstep =	1, 
+	.accel =	FB_ACCEL_NONE,
+};
+
+    /*
+     * 	Modern graphical hardware not only supports pipelines but some 
+     *  also support multiple monitors where each display can have its  
+     *  its own unique data. In this case each display could be  
+     *  represented by a separate framebuffer device thus a separate 
+     *  struct fb_info. Now the struct xxx_par represents the graphics
+     *  hardware state thus only one exist per card. In this case the 
+     *  struct xxx_par for each graphics card would be shared between 
+     *  every struct fb_info that represents a framebuffer on that card. 
+     *  This allows when one display changes it video resolution (info->var) 
+     *  the other displays know instantly. Each display can always be
+     *  aware of the entire hardware state that affects it because they share
+     *  the same xxx_par struct. The other side of the coin is multiple
+     *  graphics cards that pass data around until it is finally displayed
+     *  on one monitor. Such examples are the voodoo 1 cards and high end
+     *  NUMA graphics servers. For this case we have a bunch of pars, each
+     *  one that represents a graphics state, that belong to one struct 
+     *  fb_info. Their you would want to have *par point to a array of device
+     *  states and have each struct fb_ops function deal with all those 
+     *  states. I hope this covers every possible hardware design. If not
+     *  feel free to send your ideas at jsimmons@users.sf.net 
+     */
+
+    /*
+     *  If your driver supports multiple boards or it supports multiple 
+     *  framebuffers, you should make these arrays, or allocate them 
+     *  dynamically using framebuffer_alloc() and free them with
+     *  framebuffer_release().
+     */ 
+static struct fb_info info;
+
+    /* 
+     * Each one represents the state of the hardware. Most hardware have
+     * just one hardware state. These here represent the default state(s). 
+     */
+static struct xxx_par __initdata current_par;
+
+int xxxfb_init(void);
+
+/**
+ *	xxxfb_open - Optional function. Called when the framebuffer is
+ *		     first accessed.
+ *	@info: frame buffer structure that represents a single frame buffer
+ *	@user: tell us if the userland (value=1) or the console is accessing
+ *	       the framebuffer. 
+ *
+ *	This function is the first function called in the framebuffer api.
+ *	Usually you don't need to provide this function. The case where it 
+ *	is used is to change from a text mode hardware state to a graphics
+ * 	mode state. 
+ *
+ *	Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_open(struct fb_info *info, int user)
+{
+    return 0;
+}
+
+/**
+ *	xxxfb_release - Optional function. Called when the framebuffer 
+ *			device is closed. 
+ *	@info: frame buffer structure that represents a single frame buffer
+ *	@user: tell us if the userland (value=1) or the console is accessing
+ *	       the framebuffer. 
+ *	
+ *	Thus function is called when we close /dev/fb or the framebuffer 
+ *	console system is released. Usually you don't need this function.
+ *	The case where it is usually used is to go from a graphics state
+ *	to a text mode state.
+ *
+ *	Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_release(struct fb_info *info, int user)
+{
+    return 0;
+}
+
+/**
+ *      xxxfb_check_var - Optional function. Validates a var passed in. 
+ *      @var: frame buffer variable screen structure
+ *      @info: frame buffer structure that represents a single frame buffer 
+ *
+ *	Checks to see if the hardware supports the state requested by
+ *	var passed in. This function does not alter the hardware state!!! 
+ *	This means the data stored in struct fb_info and struct xxx_par do 
+ *      not change. This includes the var inside of struct fb_info. 
+ *	Do NOT change these. This function can be called on its own if we
+ *	intent to only test a mode and not actually set it. The stuff in 
+ *	modedb.c is a example of this. If the var passed in is slightly 
+ *	off by what the hardware can support then we alter the var PASSED in
+ *	to what we can do.
+ *
+ *      For values that are off, this function must round them _up_ to the
+ *      next value that is supported by the hardware.  If the value is
+ *      greater than the highest value supported by the hardware, then this
+ *      function must return -EINVAL.
+ *
+ *      Exception to the above rule:  Some drivers have a fixed mode, ie,
+ *      the hardware is already set at boot up, and cannot be changed.  In
+ *      this case, it is more acceptable that this function just return
+ *      a copy of the currently working var (info->var). Better is to not
+ *      implement this function, as the upper layer will do the copying
+ *      of the current var for you.
+ *
+ *      Note:  This is the only function where the contents of var can be
+ *      freely adjusted after the driver has been registered. If you find
+ *      that you have code outside of this function that alters the content
+ *      of var, then you are doing something wrong.  Note also that the
+ *      contents of info->var must be left untouched at all times after
+ *      driver registration.
+ *
+ *	Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
+{
+    /* ... */
+    return 0;	   	
+}
+
+/**
+ *      xxxfb_set_par - Optional function. Alters the hardware state.
+ *      @info: frame buffer structure that represents a single frame buffer
+ *
+ *	Using the fb_var_screeninfo in fb_info we set the resolution of the
+ *	this particular framebuffer. This function alters the par AND the
+ *	fb_fix_screeninfo stored in fb_info. It doesn't not alter var in 
+ *	fb_info since we are using that data. This means we depend on the
+ *	data in var inside fb_info to be supported by the hardware. 
+ *
+ *      This function is also used to recover/restore the hardware to a
+ *      known working state.
+ *
+ *	xxxfb_check_var is always called before xxxfb_set_par to ensure that
+ *      the contents of var is always valid.
+ *
+ *	Again if you can't change the resolution you don't need this function.
+ *
+ *      However, even if your hardware does not support mode changing,
+ *      a set_par might be needed to at least initialize the hardware to
+ *      a known working state, especially if it came back from another
+ *      process that also modifies the same hardware, such as X.
+ *
+ *      If this is the case, a combination such as the following should work:
+ *
+ *      static int xxxfb_check_var(struct fb_var_screeninfo *var,
+ *                                struct fb_info *info)
+ *      {
+ *              *var = info->var;
+ *              return 0;
+ *      }
+ *
+ *      static int xxxfb_set_par(struct fb_info *info)
+ *      {
+ *              init your hardware here
+ *      }
+ *
+ *	Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_set_par(struct fb_info *info)
+{
+    struct xxx_par *par = info->par;
+    /* ... */
+    return 0;	
+}
+
+/**
+ *  	xxxfb_setcolreg - Optional function. Sets a color register.
+ *      @regno: Which register in the CLUT we are programming 
+ *      @red: The red value which can be up to 16 bits wide 
+ *	@green: The green value which can be up to 16 bits wide 
+ *	@blue:  The blue value which can be up to 16 bits wide.
+ *	@transp: If supported, the alpha value which can be up to 16 bits wide.
+ *      @info: frame buffer info structure
+ * 
+ *  	Set a single color register. The values supplied have a 16 bit
+ *  	magnitude which needs to be scaled in this function for the hardware. 
+ *	Things to take into consideration are how many color registers, if
+ *	any, are supported with the current color visual. With truecolor mode
+ *	no color palettes are supported. Here a pseudo palette is created
+ *	which we store the value in pseudo_palette in struct fb_info. For
+ *	pseudocolor mode we have a limited color palette. To deal with this
+ *	we can program what color is displayed for a particular pixel value.
+ *	DirectColor is similar in that we can program each color field. If
+ *	we have a static colormap we don't need to implement this function. 
+ * 
+ *	Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_setcolreg(unsigned regno, unsigned red, unsigned green,
+			   unsigned blue, unsigned transp,
+			   struct fb_info *info)
+{
+    if (regno >= 256)  /* no. of hw registers */
+       return -EINVAL;
+    /*
+     * Program hardware... do anything you want with transp
+     */
+
+    /* grayscale works only partially under directcolor */
+    if (info->var.grayscale) {
+       /* grayscale = 0.30*R + 0.59*G + 0.11*B */
+       red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
+    }
+
+    /* Directcolor:
+     *   var->{color}.offset contains start of bitfield
+     *   var->{color}.length contains length of bitfield
+     *   {hardwarespecific} contains width of DAC
+     *   pseudo_palette[X] is programmed to (X << red.offset) |
+     *                                      (X << green.offset) |
+     *                                      (X << blue.offset)
+     *   RAMDAC[X] is programmed to (red, green, blue)
+     *   color depth = SUM(var->{color}.length)
+     *
+     * Pseudocolor:
+     *    var->{color}.offset is 0 unless the palette index takes less than
+     *                        bits_per_pixel bits and is stored in the upper
+     *                        bits of the pixel value
+     *    var->{color}.length is set so that 1 << length is the number of
+     *                        available palette entries
+     *    pseudo_palette is not used
+     *    RAMDAC[X] is programmed to (red, green, blue)
+     *    color depth = var->{color}.length
+     *
+     * Static pseudocolor:
+     *    same as Pseudocolor, but the RAMDAC is not programmed (read-only)
+     *
+     * Mono01/Mono10:
+     *    Has only 2 values, black on white or white on black (fg on bg),
+     *    var->{color}.offset is 0
+     *    white = (1 << var->{color}.length) - 1, black = 0
+     *    pseudo_palette is not used
+     *    RAMDAC does not exist
+     *    color depth is always 2
+     *
+     * Truecolor:
+     *    does not use RAMDAC (usually has 3 of them).
+     *    var->{color}.offset contains start of bitfield
+     *    var->{color}.length contains length of bitfield
+     *    pseudo_palette is programmed to (red << red.offset) |
+     *                                    (green << green.offset) |
+     *                                    (blue << blue.offset) |
+     *                                    (transp << transp.offset)
+     *    RAMDAC does not exist
+     *    color depth = SUM(var->{color}.length})
+     *
+     *  The color depth is used by fbcon for choosing the logo and also
+     *  for color palette transformation if color depth < 4
+     *
+     *  As can be seen from the above, the field bits_per_pixel is _NOT_
+     *  a criteria for describing the color visual.
+     *
+     *  A common mistake is assuming that bits_per_pixel <= 8 is pseudocolor,
+     *  and higher than that, true/directcolor.  This is incorrect, one needs
+     *  to look at the fix->visual.
+     *
+     *  Another common mistake is using bits_per_pixel to calculate the color
+     *  depth.  The bits_per_pixel field does not directly translate to color
+     *  depth. You have to compute for the color depth (using the color
+     *  bitfields) and fix->visual as seen above.
+     */
+
+    /*
+     * This is the point where the color is converted to something that
+     * is acceptable by the hardware.
+     */
+#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
+    red = CNVT_TOHW(red, info->var.red.length);
+    green = CNVT_TOHW(green, info->var.green.length);
+    blue = CNVT_TOHW(blue, info->var.blue.length);
+    transp = CNVT_TOHW(transp, info->var.transp.length);
+#undef CNVT_TOHW
+    /*
+     * This is the point where the function feeds the color to the hardware
+     * palette after converting the colors to something acceptable by
+     * the hardware. Note, only FB_VISUAL_DIRECTCOLOR and
+     * FB_VISUAL_PSEUDOCOLOR visuals need to write to the hardware palette.
+     * If you have code that writes to the hardware CLUT, and it's not
+     * any of the above visuals, then you are doing something wrong.
+     */
+    if (info->fix.visual == FB_VISUAL_DIRECTCOLOR ||
+	info->fix.visual == FB_VISUAL_TRUECOLOR)
+	    write_{red|green|blue|transp}_to_clut();
+
+    /* This is the point were you need to fill up the contents of
+     * info->pseudo_palette. This structure is used _only_ by fbcon, thus
+     * it only contains 16 entries to match the number of colors supported
+     * by the console. The pseudo_palette is used only if the visual is
+     * in directcolor or truecolor mode.  With other visuals, the
+     * pseudo_palette is not used. (This might change in the future.)
+     *
+     * The contents of the pseudo_palette is in raw pixel format.  Ie, each
+     * entry can be written directly to the framebuffer without any conversion.
+     * The pseudo_palette is (void *).  However, if using the generic
+     * drawing functions (cfb_imageblit, cfb_fillrect), the pseudo_palette
+     * must be casted to (u32 *) _regardless_ of the bits per pixel. If the
+     * driver is using its own drawing functions, then it can use whatever
+     * size it wants.
+     */
+    if (info->fix.visual == FB_VISUAL_TRUECOLOR ||
+	info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
+	    u32 v;
+
+	    if (regno >= 16)
+		    return -EINVAL;
+
+	    v = (red << info->var.red.offset) |
+		    (green << info->var.green.offset) |
+		    (blue << info->var.blue.offset) |
+		    (transp << info->var.transp.offset);
+
+	    ((u32*)(info->pseudo_palette))[regno] = v;
+    }
+
+    /* ... */
+    return 0;
+}
+
+/**
+ *      xxxfb_pan_display - NOT a required function. Pans the display.
+ *      @var: frame buffer variable screen structure
+ *      @info: frame buffer structure that represents a single frame buffer
+ *
+ *	Pan (or wrap, depending on the `vmode' field) the display using the
+ *  	`xoffset' and `yoffset' fields of the `var' structure.
+ *  	If the values don't fit, return -EINVAL.
+ *
+ *      Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_pan_display(struct fb_var_screeninfo *var,
+			     struct fb_info *info)
+{
+    /*
+     * If your hardware does not support panning, _do_ _not_ implement this
+     * function. Creating a dummy function will just confuse user apps.
+     */
+
+    /*
+     * Note that even if this function is fully functional, a setting of
+     * 0 in both xpanstep and ypanstep means that this function will never
+     * get called.
+     */
+
+    /* ... */
+    return 0;
+}
+
+/**
+ *      xxxfb_blank - NOT a required function. Blanks the display.
+ *      @blank_mode: the blank mode we want. 
+ *      @info: frame buffer structure that represents a single frame buffer
+ *
+ *      Blank the screen if blank_mode != FB_BLANK_UNBLANK, else unblank.
+ *      Return 0 if blanking succeeded, != 0 if un-/blanking failed due to
+ *      e.g. a video mode which doesn't support it.
+ *
+ *      Implements VESA suspend and powerdown modes on hardware that supports
+ *      disabling hsync/vsync:
+ *
+ *      FB_BLANK_NORMAL = display is blanked, syncs are on.
+ *      FB_BLANK_HSYNC_SUSPEND = hsync off
+ *      FB_BLANK_VSYNC_SUSPEND = vsync off
+ *      FB_BLANK_POWERDOWN =  hsync and vsync off
+ *
+ *      If implementing this function, at least support FB_BLANK_UNBLANK.
+ *      Return !0 for any modes that are unimplemented.
+ *
+ */
+static int xxxfb_blank(int blank_mode, struct fb_info *info)
+{
+    /* ... */
+    return 0;
+}
+
+/* ------------ Accelerated Functions --------------------- */
+
+/*
+ * We provide our own functions if we have hardware acceleration
+ * or non packed pixel format layouts. If we have no hardware 
+ * acceleration, we can use a generic unaccelerated function. If using
+ * a pack pixel format just use the functions in cfb_*.c. Each file 
+ * has one of the three different accel functions we support.
+ */
+
+/**
+ *      xxxfb_fillrect - REQUIRED function. Can use generic routines if 
+ *		 	 non acclerated hardware and packed pixel based.
+ *			 Draws a rectangle on the screen.		
+ *
+ *      @info: frame buffer structure that represents a single frame buffer
+ *	@region: The structure representing the rectangular region we 
+ *		 wish to draw to.
+ *
+ *	This drawing operation places/removes a retangle on the screen 
+ *	depending on the rastering operation with the value of color which
+ *	is in the current color depth format.
+ */
+void xxxfb_fillrect(struct fb_info *p, const struct fb_fillrect *region)
+{
+/*	Meaning of struct fb_fillrect
+ *
+ *	@dx: The x and y corrdinates of the upper left hand corner of the 
+ *	@dy: area we want to draw to. 
+ *	@width: How wide the rectangle is we want to draw.
+ *	@height: How tall the rectangle is we want to draw.
+ *	@color:	The color to fill in the rectangle with. 
+ *	@rop: The raster operation. We can draw the rectangle with a COPY
+ *	      of XOR which provides erasing effect. 
+ */
+}
+
+/**
+ *      xxxfb_copyarea - REQUIRED function. Can use generic routines if
+ *                       non acclerated hardware and packed pixel based.
+ *                       Copies one area of the screen to another area.
+ *
+ *      @info: frame buffer structure that represents a single frame buffer
+ *      @area: Structure providing the data to copy the framebuffer contents
+ *	       from one region to another.
+ *
+ *      This drawing operation copies a rectangular area from one area of the
+ *	screen to another area.
+ */
+void xxxfb_copyarea(struct fb_info *p, const struct fb_copyarea *area) 
+{
+/*
+ *      @dx: The x and y coordinates of the upper left hand corner of the
+ *	@dy: destination area on the screen.
+ *      @width: How wide the rectangle is we want to copy.
+ *      @height: How tall the rectangle is we want to copy.
+ *      @sx: The x and y coordinates of the upper left hand corner of the
+ *      @sy: source area on the screen.
+ */
+}
+
+
+/**
+ *      xxxfb_imageblit - REQUIRED function. Can use generic routines if
+ *                        non acclerated hardware and packed pixel based.
+ *                        Copies a image from system memory to the screen. 
+ *
+ *      @info: frame buffer structure that represents a single frame buffer
+ *	@image:	structure defining the image.
+ *
+ *      This drawing operation draws a image on the screen. It can be a 
+ *	mono image (needed for font handling) or a color image (needed for
+ *	tux). 
+ */
+void xxxfb_imageblit(struct fb_info *p, const struct fb_image *image) 
+{
+/*
+ *      @dx: The x and y coordinates of the upper left hand corner of the
+ *	@dy: destination area to place the image on the screen.
+ *      @width: How wide the image is we want to copy.
+ *      @height: How tall the image is we want to copy.
+ *      @fg_color: For mono bitmap images this is color data for     
+ *      @bg_color: the foreground and background of the image to
+ *		   write directly to the frmaebuffer.
+ *	@depth:	How many bits represent a single pixel for this image.
+ *	@data: The actual data used to construct the image on the display.
+ *	@cmap: The colormap used for color images.   
+ */
+
+/*
+ * The generic function, cfb_imageblit, expects that the bitmap scanlines are
+ * padded to the next byte.  Most hardware accelerators may require padding to
+ * the next u16 or the next u32.  If that is the case, the driver can specify
+ * this by setting info->pixmap.scan_align = 2 or 4.  See a more
+ * comprehensive description of the pixmap below.
+ */
+}
+
+/**
+ *	xxxfb_cursor - 	OPTIONAL. If your hardware lacks support
+ *			for a cursor, leave this field NULL.
+ *
+ *      @info: frame buffer structure that represents a single frame buffer
+ *	@cursor: structure defining the cursor to draw.
+ *
+ *      This operation is used to set or alter the properities of the
+ *	cursor.
+ *
+ *	Returns negative errno on error, or zero on success.
+ */
+int xxxfb_cursor(struct fb_info *info, struct fb_cursor *cursor)
+{
+/*
+ *      @set: 	Which fields we are altering in struct fb_cursor 
+ *	@enable: Disable or enable the cursor 
+ *      @rop: 	The bit operation we want to do. 
+ *      @mask:  This is the cursor mask bitmap. 
+ *      @dest:  A image of the area we are going to display the cursor.
+ *		Used internally by the driver.	 
+ *      @hot:	The hot spot. 
+ *	@image:	The actual data for the cursor image.
+ *
+ *      NOTES ON FLAGS (cursor->set):
+ *
+ *      FB_CUR_SETIMAGE - the cursor image has changed (cursor->image.data)
+ *      FB_CUR_SETPOS   - the cursor position has changed (cursor->image.dx|dy)
+ *      FB_CUR_SETHOT   - the cursor hot spot has changed (cursor->hot.dx|dy)
+ *      FB_CUR_SETCMAP  - the cursor colors has changed (cursor->fg_color|bg_color)
+ *      FB_CUR_SETSHAPE - the cursor bitmask has changed (cursor->mask)
+ *      FB_CUR_SETSIZE  - the cursor size has changed (cursor->width|height)
+ *      FB_CUR_SETALL   - everything has changed
+ *
+ *      NOTES ON ROPs (cursor->rop, Raster Operation)
+ *
+ *      ROP_XOR         - cursor->image.data XOR cursor->mask
+ *      ROP_COPY        - curosr->image.data AND cursor->mask
+ *
+ *      OTHER NOTES:
+ *
+ *      - fbcon only supports a 2-color cursor (cursor->image.depth = 1)
+ *      - The fb_cursor structure, @cursor, _will_ always contain valid
+ *        fields, whether any particular bitfields in cursor->set is set
+ *        or not.
+ */
+}
+
+/**
+ *	xxxfb_rotate -  NOT a required function. If your hardware
+ *			supports rotation the whole screen then 
+ *			you would provide a hook for this. 
+ *
+ *      @info: frame buffer structure that represents a single frame buffer
+ *	@angle: The angle we rotate the screen.   
+ *
+ *      This operation is used to set or alter the properities of the
+ *	cursor.
+ */
+void xxxfb_rotate(struct fb_info *info, int angle)
+{
+/* Will be deprecated */
+}
+
+/**
+ *	xxxfb_sync - NOT a required function. Normally the accel engine 
+ *		     for a graphics card take a specific amount of time.
+ *		     Often we have to wait for the accelerator to finish
+ *		     its operation before we can write to the framebuffer
+ *		     so we can have consistent display output. 
+ *
+ *      @info: frame buffer structure that represents a single frame buffer
+ *
+ *      If the driver has implemented its own hardware-based drawing function,
+ *      implementing this function is highly recommended.
+ */
+int xxxfb_sync(struct fb_info *info)
+{
+	return 0;
+}
+
+    /*
+     *  Frame buffer operations
+     */
+
+static struct fb_ops xxxfb_ops = {
+	.owner		= THIS_MODULE,
+	.fb_open	= xxxfb_open,
+	.fb_read	= xxxfb_read,
+	.fb_write	= xxxfb_write,
+	.fb_release	= xxxfb_release,
+	.fb_check_var	= xxxfb_check_var,
+	.fb_set_par	= xxxfb_set_par,
+	.fb_setcolreg	= xxxfb_setcolreg,
+	.fb_blank	= xxxfb_blank,
+	.fb_pan_display	= xxxfb_pan_display,
+	.fb_fillrect	= xxxfb_fillrect, 	/* Needed !!! */
+	.fb_copyarea	= xxxfb_copyarea,	/* Needed !!! */
+	.fb_imageblit	= xxxfb_imageblit,	/* Needed !!! */
+	.fb_cursor	= xxxfb_cursor,		/* Optional !!! */
+	.fb_rotate	= xxxfb_rotate,
+	.fb_sync	= xxxfb_sync,
+	.fb_ioctl	= xxxfb_ioctl,
+	.fb_mmap	= xxxfb_mmap,
+};
+
+/* ------------------------------------------------------------------------- */
+
+    /*
+     *  Initialization
+     */
+
+/* static int __init xxfb_probe (struct platform_device *pdev) -- for platform devs */
+static int xxxfb_probe(struct pci_dev *dev, const struct pci_device_id *ent)
+{
+    struct fb_info *info;
+    struct xxx_par *par;
+    struct device *device = &dev->dev; /* or &pdev->dev */
+    int cmap_len, retval;	
+   
+    /*
+     * Dynamically allocate info and par
+     */
+    info = framebuffer_alloc(sizeof(struct xxx_par), device);
+
+    if (!info) {
+	    /* goto error path */
+    }
+
+    par = info->par;
+
+    /* 
+     * Here we set the screen_base to the virtual memory address
+     * for the framebuffer. Usually we obtain the resource address
+     * from the bus layer and then translate it to virtual memory
+     * space via ioremap. Consult ioport.h. 
+     */
+    info->screen_base = framebuffer_virtual_memory;
+    info->fbops = &xxxfb_ops;
+    info->fix = xxxfb_fix;
+    info->pseudo_palette = pseudo_palette; /* The pseudopalette is an
+					    * 16-member array
+					    */
+    /*
+     * Set up flags to indicate what sort of acceleration your
+     * driver can provide (pan/wrap/copyarea/etc.) and whether it
+     * is a module -- see FBINFO_* in include/linux/fb.h
+     *
+     * If your hardware can support any of the hardware accelerated functions
+     * fbcon performance will improve if info->flags is set properly.
+     *
+     * FBINFO_HWACCEL_COPYAREA - hardware moves
+     * FBINFO_HWACCEL_FILLRECT - hardware fills
+     * FBINFO_HWACCEL_IMAGEBLIT - hardware mono->color expansion
+     * FBINFO_HWACCEL_YPAN - hardware can pan display in y-axis
+     * FBINFO_HWACCEL_YWRAP - hardware can wrap display in y-axis
+     * FBINFO_HWACCEL_DISABLED - supports hardware accels, but disabled
+     * FBINFO_READS_FAST - if set, prefer moves over mono->color expansion
+     * FBINFO_MISC_TILEBLITTING - hardware can do tile blits
+     *
+     * NOTE: These are for fbcon use only.
+     */
+    info->flags = FBINFO_DEFAULT;
+
+/********************* This stage is optional ******************************/
+     /*
+     * The struct pixmap is a scratch pad for the drawing functions. This
+     * is where the monochrome bitmap is constructed by the higher layers
+     * and then passed to the accelerator.  For drivers that uses
+     * cfb_imageblit, you can skip this part.  For those that have a more
+     * rigorous requirement, this stage is needed
+     */
+
+    /* PIXMAP_SIZE should be small enough to optimize drawing, but not
+     * large enough that memory is wasted.  A safe size is
+     * (max_xres * max_font_height/8). max_xres is driver dependent,
+     * max_font_height is 32.
+     */
+    info->pixmap.addr = kmalloc(PIXMAP_SIZE, GFP_KERNEL);
+    if (!info->pixmap.addr) {
+	    /* goto error */
+    }
+
+    info->pixmap.size = PIXMAP_SIZE;
+
+    /*
+     * FB_PIXMAP_SYSTEM - memory is in system ram
+     * FB_PIXMAP_IO     - memory is iomapped
+     * FB_PIXMAP_SYNC   - if set, will call fb_sync() per access to pixmap,
+     *                    usually if FB_PIXMAP_IO is set.
+     *
+     * Currently, FB_PIXMAP_IO is unimplemented.
+     */
+    info->pixmap.flags = FB_PIXMAP_SYSTEM;
+
+    /*
+     * scan_align is the number of padding for each scanline.  It is in bytes.
+     * Thus for accelerators that need padding to the next u32, put 4 here.
+     */
+    info->pixmap.scan_align = 4;
+
+    /*
+     * buf_align is the amount to be padded for the buffer. For example,
+     * the i810fb needs a scan_align of 2 but expects it to be fed with
+     * dwords, so a buf_align = 4 is required.
+     */
+    info->pixmap.buf_align = 4;
+
+    /* access_align is how many bits can be accessed from the framebuffer
+     * ie. some epson cards allow 16-bit access only.  Most drivers will
+     * be safe with u32 here.
+     *
+     * NOTE: This field is currently unused.
+     */
+    info->pixmap.access_align = 32;
+/***************************** End optional stage ***************************/
+
+    /*
+     * This should give a reasonable default video mode. The following is
+     * done when we can set a video mode. 
+     */
+    if (!mode_option)
+	mode_option = "640x480@60";	 	
+
+    retval = fb_find_mode(&info->var, info, mode_option, NULL, 0, NULL, 8);
+  
+    if (!retval || retval == 4)
+	return -EINVAL;			
+
+    /* This has to be done! */
+    if (fb_alloc_cmap(&info->cmap, cmap_len, 0))
+	return -ENOMEM;
+	
+    /* 
+     * The following is done in the case of having hardware with a static 
+     * mode. If we are setting the mode ourselves we don't call this. 
+     */	
+    info->var = xxxfb_var;
+
+    /*
+     * For drivers that can...
+     */
+    xxxfb_check_var(&info->var, info);
+
+    /*
+     * Does a call to fb_set_par() before register_framebuffer needed?  This
+     * will depend on you and the hardware.  If you are sure that your driver
+     * is the only device in the system, a call to fb_set_par() is safe.
+     *
+     * Hardware in x86 systems has a VGA core.  Calling set_par() at this
+     * point will corrupt the VGA console, so it might be safer to skip a
+     * call to set_par here and just allow fbcon to do it for you.
+     */
+    /* xxxfb_set_par(info); */
+
+    if (register_framebuffer(info) < 0) {
+	fb_dealloc_cmap(&info->cmap);
+	return -EINVAL;
+    }
+    fb_info(info, "%s frame buffer device\n", info->fix.id);
+    pci_set_drvdata(dev, info); /* or platform_set_drvdata(pdev, info) */
+    return 0;
+}
+
+    /*
+     *  Cleanup
+     */
+/* static void xxxfb_remove(struct platform_device *pdev) */
+static void xxxfb_remove(struct pci_dev *dev)
+{
+	struct fb_info *info = pci_get_drvdata(dev);
+	/* or platform_get_drvdata(pdev); */
+
+	if (info) {
+		unregister_framebuffer(info);
+		fb_dealloc_cmap(&info->cmap);
+		/* ... */
+		framebuffer_release(info);
+	}
+}
+
+#ifdef CONFIG_PCI
+#ifdef CONFIG_PM
+/**
+ *	xxxfb_suspend - Optional but recommended function. Suspend the device.
+ *	@dev: PCI device
+ *	@msg: the suspend event code.
+ *
+ *      See Documentation/power/devices.txt for more information
+ */
+static int xxxfb_suspend(struct pci_dev *dev, pm_message_t msg)
+{
+	struct fb_info *info = pci_get_drvdata(dev);
+	struct xxxfb_par *par = info->par;
+
+	/* suspend here */
+	return 0;
+}
+
+/**
+ *	xxxfb_resume - Optional but recommended function. Resume the device.
+ *	@dev: PCI device
+ *
+ *      See Documentation/power/devices.txt for more information
+ */
+static int xxxfb_resume(struct pci_dev *dev)
+{
+	struct fb_info *info = pci_get_drvdata(dev);
+	struct xxxfb_par *par = info->par;
+
+	/* resume here */
+	return 0;
+}
+#else
+#define xxxfb_suspend NULL
+#define xxxfb_resume NULL
+#endif /* CONFIG_PM */
+
+static struct pci_device_id xxxfb_id_table[] = {
+	{ PCI_VENDOR_ID_XXX, PCI_DEVICE_ID_XXX,
+	  PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY << 16,
+	  PCI_CLASS_MASK, 0 },
+	{ 0, }
+};
+
+/* For PCI drivers */
+static struct pci_driver xxxfb_driver = {
+	.name =		"xxxfb",
+	.id_table =	xxxfb_id_table,
+	.probe =	xxxfb_probe,
+	.remove =	xxxfb_remove,
+	.suspend =      xxxfb_suspend, /* optional but recommended */
+	.resume =       xxxfb_resume,  /* optional but recommended */
+};
+
+MODULE_DEVICE_TABLE(pci, xxxfb_id_table);
+
+int __init xxxfb_init(void)
+{
+	/*
+	 *  For kernel boot options (in 'video=xxxfb:<options>' format)
+	 */
+#ifndef MODULE
+	char *option = NULL;
+
+	if (fb_get_options("xxxfb", &option))
+		return -ENODEV;
+	xxxfb_setup(option);
+#endif
+
+	return pci_register_driver(&xxxfb_driver);
+}
+
+static void __exit xxxfb_exit(void)
+{
+	pci_unregister_driver(&xxxfb_driver);
+}
+#else /* non PCI, platform drivers */
+#include <linux/platform_device.h>
+/* for platform devices */
+
+#ifdef CONFIG_PM
+/**
+ *	xxxfb_suspend - Optional but recommended function. Suspend the device.
+ *	@dev: platform device
+ *	@msg: the suspend event code.
+ *
+ *      See Documentation/power/devices.txt for more information
+ */
+static int xxxfb_suspend(struct platform_device *dev, pm_message_t msg)
+{
+	struct fb_info *info = platform_get_drvdata(dev);
+	struct xxxfb_par *par = info->par;
+
+	/* suspend here */
+	return 0;
+}
+
+/**
+ *	xxxfb_resume - Optional but recommended function. Resume the device.
+ *	@dev: platform device
+ *
+ *      See Documentation/power/devices.txt for more information
+ */
+static int xxxfb_resume(struct platform_dev *dev)
+{
+	struct fb_info *info = platform_get_drvdata(dev);
+	struct xxxfb_par *par = info->par;
+
+	/* resume here */
+	return 0;
+}
+#else
+#define xxxfb_suspend NULL
+#define xxxfb_resume NULL
+#endif /* CONFIG_PM */
+
+static struct platform_device_driver xxxfb_driver = {
+	.probe = xxxfb_probe,
+	.remove = xxxfb_remove,
+	.suspend = xxxfb_suspend, /* optional but recommended */
+	.resume = xxxfb_resume,   /* optional but recommended */
+	.driver = {
+		.name = "xxxfb",
+	},
+};
+
+static struct platform_device *xxxfb_device;
+
+#ifndef MODULE
+    /*
+     *  Setup
+     */
+
+/*
+ * Only necessary if your driver takes special options,
+ * otherwise we fall back on the generic fb_setup().
+ */
+int __init xxxfb_setup(char *options)
+{
+    /* Parse user specified options (`video=xxxfb:') */
+}
+#endif /* MODULE */
+
+static int __init xxxfb_init(void)
+{
+	int ret;
+	/*
+	 *  For kernel boot options (in 'video=xxxfb:<options>' format)
+	 */
+#ifndef MODULE
+	char *option = NULL;
+
+	if (fb_get_options("xxxfb", &option))
+		return -ENODEV;
+	xxxfb_setup(option);
+#endif
+	ret = platform_driver_register(&xxxfb_driver);
+
+	if (!ret) {
+		xxxfb_device = platform_device_register_simple("xxxfb", 0,
+								NULL, 0);
+
+		if (IS_ERR(xxxfb_device)) {
+			platform_driver_unregister(&xxxfb_driver);
+			ret = PTR_ERR(xxxfb_device);
+		}
+	}
+
+	return ret;
+}
+
+static void __exit xxxfb_exit(void)
+{
+	platform_device_unregister(xxxfb_device);
+	platform_driver_unregister(&xxxfb_driver);
+}
+#endif /* CONFIG_PCI */
+
+/* ------------------------------------------------------------------------- */
+
+
+    /*
+     *  Modularization
+     */
+
+module_init(xxxfb_init);
+module_exit(xxxfb_exit);
+
+MODULE_LICENSE("GPL");