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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/video/skeletonfb.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
Diffstat (limited to 'drivers/video/skeletonfb.c')
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diff --git a/drivers/video/skeletonfb.c b/drivers/video/skeletonfb.c
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+/*
+ * 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 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/tty.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+
+    /*
+     *  This is just simple sample code.
+     *
+     *  No warranty that it actually compiles.
+     *  Even less warranty that it actually works :-)
+     */
+
+/*
+ *  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 __initdata = {
+	.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 kmalloc()). 
+     */ 
+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);
+int xxxfb_setup(char*);
+
+/**
+ *	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(const 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(const 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. If the hardware doesn't support mode change 
+ * 	a -EINVAL will be returned by the upper layers. You don't need to 
+ *	implement this function then. If you hardware doesn't support 
+ *	changing the resolution then this function is not needed. In this
+ *	case the driver woudl just provide a var that represents the static
+ *	state the screen is in.
+ *
+ *	Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
+{
+    const struct xxx_par *par = (const struct xxx_par *) info->par;
+    /* ... */
+    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. 
+ *	xxxfb_check_var is always called before xxxfb_set_par to ensure this.
+ *	Again if you can't change the resolution you don't need this function.
+ *
+ *	Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_set_par(struct fb_info *info)
+{
+    struct xxx_par *par = (struct xxx_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,
+			   const 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
+     *   cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
+     *   RAMDAC[X] is programmed to (red, green, blue)
+     *
+     * Pseudocolor:
+     *    uses offset = 0 && length = DAC register width.
+     *    var->{color}.offset is 0
+     *    var->{color}.length contains widht of DAC
+     *    cmap is not used
+     *    DAC[X] is programmed to (red, green, blue)
+     * Truecolor:
+     *    does not use RAMDAC (usually has 3 of them).
+     *    var->{color}.offset contains start of bitfield
+     *    var->{color}.length contains length of bitfield
+     *    cmap is programmed to (red << red.offset) | (green << green.offset) |
+     *                      (blue << blue.offset) | (transp << transp.offset)
+     *    RAMDAC does not exist
+     */
+#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
+    switch (info->fix.visual) {
+       case FB_VISUAL_TRUECOLOR:
+       case FB_VISUAL_PSEUDOCOLOR:
+               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);
+               break;
+       case FB_VISUAL_DIRECTCOLOR:
+	       /* example here assumes 8 bit DAC. Might be different 
+		* for your hardware */	
+               red = CNVT_TOHW(red, 8);       
+               green = CNVT_TOHW(green, 8);
+               blue = CNVT_TOHW(blue, 8);
+               /* hey, there is bug in transp handling... */
+               transp = CNVT_TOHW(transp, 8);
+               break;
+    }
+#undef CNVT_TOHW
+    /* Truecolor has hardware independent palette */
+    if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
+       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);
+
+       switch (info->var.bits_per_pixel) {
+		case 8:
+			/* Yes some hand held devices have this. */ 
+           		((u8*)(info->pseudo_palette))[regno] = v;
+			break;	
+   		case 16:
+           		((u16*)(info->pseudo_palette))[regno] = v;
+			break;
+		case 24:
+		case 32:	
+           		((u32*)(info->pseudo_palette))[regno] = v;
+			break;
+       }
+       return 0;
+    }
+    /* ... */
+    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,
+			     const struct fb_info *info)
+{
+    /* ... */
+    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 != 0, 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:
+ *      blank_mode == 2: suspend vsync
+ *      blank_mode == 3: suspend hsync
+ *      blank_mode == 4: powerdown
+ *
+ *      Returns negative errno on error, or zero on success.
+ *
+ */
+static int xxxfb_blank(int blank_mode, const 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 xxfb_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.   
+ */
+}
+
+/**
+ *	xxxfb_cursor - 	REQUIRED function. If your hardware lacks support
+ *			for a cursor you can use the default cursor whose
+ *			function is called soft_cursor. It will always 
+ *			work since it uses xxxfb_imageblit function which 
+ *			is required. 	  	 
+ *
+ *      @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)
+{
+}
+
+/**
+ *	xxxfb_poll - NOT a required function. The purpose of this
+ *		     function is to provide a way for some process
+ *		     to wait until a specific hardware event occurs
+ *		     for the framebuffer device.
+ * 				 
+ *      @info: frame buffer structure that represents a single frame buffer
+ *	@wait: poll table where we store process that await a event.     
+ */
+void xxxfb_poll(struct fb_info *info, poll_table *wait)
+{
+}
+
+/**
+ *	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
+ */
+void xxxfb_sync(struct fb_info *info)
+{
+}
+
+    /*
+     *  Initialization
+     */
+
+int __init xxxfb_init(void)
+{
+    int cmap_len, retval;	
+   
+    /*
+     *  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
+
+    /* 
+     * 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;
+
+    /*
+     * 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
+     */
+    info.flags = FBINFO_DEFAULT;
+    info.par = current_par;
+
+    /*
+     * 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 been done !!! */	
+    fb_alloc_cmap(&info.cmap, cmap_len, 0);
+	
+    /* 
+     * 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;
+	
+    if (register_framebuffer(&info) < 0)
+	return -EINVAL;
+    printk(KERN_INFO "fb%d: %s frame buffer device\n", info.node,
+	   info.fix.id);
+    return 0;
+}
+
+    /*
+     *  Cleanup
+     */
+
+static void __exit xxxfb_cleanup(void)
+{
+    /*
+     *  If your driver supports multiple boards, you should unregister and
+     *  clean up all instances.
+     */
+
+    unregister_framebuffer(info);
+    fb_dealloc_cmap(&info.cmap);
+    /* ... */
+}
+
+    /*
+     *  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 speficied options (`video=xxxfb:') */
+}
+
+/* ------------------------------------------------------------------------- */
+
+    /*
+     *  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,		/* Needed !!! */
+	.fb_rotate	= xxxfb_rotate,
+	.fb_poll	= xxxfb_poll,
+	.fb_sync	= xxxfb_sync,
+	.fb_ioctl	= xxxfb_ioctl,
+	.fb_mmap	= xxxfb_mmap,	
+};
+
+/* ------------------------------------------------------------------------- */
+
+
+    /*
+     *  Modularization
+     */
+
+module_init(xxxfb_init);
+module_exit(xxxfb_cleanup);
+
+MODULE_LICENSE("GPL");