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1/*2 * linux/drivers/video/skeletonfb.c -- Skeleton for a frame buffer device3 *4 *  Modified to new api Jan 2001 by James Simmons (jsimmons@transvirtual.com)5 *6 *  Created 28 Dec 1997 by Geert Uytterhoeven7 *8 *9 *  I have started rewriting this driver as a example of the upcoming new API10 *  The primary goal is to remove the console code from fbdev and place it11 *  into fbcon.c. This reduces the code and makes writing a new fbdev driver12 *  easy since the author doesn't need to worry about console internals. It13 *  also allows the ability to run fbdev without a console/tty system on top14 *  of it.15 *16 *  First the roles of struct fb_info and struct display have changed. Struct17 *  display will go away. The way the new framebuffer console code will18 *  work is that it will act to translate data about the tty/console in19 *  struct vc_data to data in a device independent way in struct fb_info. Then20 *  various functions in struct fb_ops will be called to store the device21 *  dependent state in the par field in struct fb_info and to change the22 *  hardware to that state. This allows a very clean separation of the fbdev23 *  layer from the console layer. It also allows one to use fbdev on its own24 *  which is a bounus for embedded devices. The reason this approach works is25 *  for each framebuffer device when used as a tty/console device is allocated26 *  a set of virtual terminals to it. Only one virtual terminal can be active27 *  per framebuffer device. We already have all the data we need in struct28 *  vc_data so why store a bunch of colormaps and other fbdev specific data29 *  per virtual terminal.30 *31 *  As you can see doing this makes the con parameter pretty much useless32 *  for struct fb_ops functions, as it should be. Also having struct33 *  fb_var_screeninfo and other data in fb_info pretty much eliminates the34 *  need for get_fix and get_var. Once all drivers use the fix, var, and cmap35 *  fbcon can be written around these fields. This will also eliminate the36 *  need to regenerate struct fb_var_screeninfo, struct fb_fix_screeninfo37 *  struct fb_cmap every time get_var, get_fix, get_cmap functions are called38 *  as many drivers do now.39 *40 *  This file is subject to the terms and conditions of the GNU General Public41 *  License. See the file COPYING in the main directory of this archive for42 *  more details.43 */44 45#include <linux/aperture.h>46#include <linux/module.h>47#include <linux/kernel.h>48#include <linux/errno.h>49#include <linux/string.h>50#include <linux/mm.h>51#include <linux/slab.h>52#include <linux/delay.h>53#include <linux/fb.h>54#include <linux/init.h>55#include <linux/pci.h>56 57    /*58     *  This is just simple sample code.59     *60     *  No warranty that it actually compiles.61     *  Even less warranty that it actually works :-)62     */63 64/*65 * Driver data66 */67static char *mode_option;68 69/*70 *  If your driver supports multiple boards, you should make the71 *  below data types arrays, or allocate them dynamically (using kmalloc()).72 */73 74/*75 * This structure defines the hardware state of the graphics card. Normally76 * you place this in a header file in linux/include/video. This file usually77 * also includes register information. That allows other driver subsystems78 * and userland applications the ability to use the same header file to79 * avoid duplicate work and easy porting of software.80 */81struct xxx_par;82 83/*84 * Here we define the default structs fb_fix_screeninfo and fb_var_screeninfo85 * if we don't use modedb. If we do use modedb see xxxfb_init how to use it86 * to get a fb_var_screeninfo. Otherwise define a default var as well.87 */88static const struct fb_fix_screeninfo xxxfb_fix = {89	.id =		"FB's name",90	.type =		FB_TYPE_PACKED_PIXELS,91	.visual =	FB_VISUAL_PSEUDOCOLOR,92	.xpanstep =	1,93	.ypanstep =	1,94	.ywrapstep =	1,95	.accel =	FB_ACCEL_NONE,96};97 98    /*99     * 	Modern graphical hardware not only supports pipelines but some100     *  also support multiple monitors where each display can have101     *  its own unique data. In this case each display could be102     *  represented by a separate framebuffer device thus a separate103     *  struct fb_info. Now the struct xxx_par represents the graphics104     *  hardware state thus only one exist per card. In this case the105     *  struct xxx_par for each graphics card would be shared between106     *  every struct fb_info that represents a framebuffer on that card.107     *  This allows when one display changes it video resolution (info->var)108     *  the other displays know instantly. Each display can always be109     *  aware of the entire hardware state that affects it because they share110     *  the same xxx_par struct. The other side of the coin is multiple111     *  graphics cards that pass data around until it is finally displayed112     *  on one monitor. Such examples are the voodoo 1 cards and high end113     *  NUMA graphics servers. For this case we have a bunch of pars, each114     *  one that represents a graphics state, that belong to one struct115     *  fb_info. Their you would want to have *par point to a array of device116     *  states and have each struct fb_ops function deal with all those117     *  states. I hope this covers every possible hardware design. If not118     *  feel free to send your ideas at jsimmons@users.sf.net119     */120 121    /*122     *  If your driver supports multiple boards or it supports multiple123     *  framebuffers, you should make these arrays, or allocate them124     *  dynamically using framebuffer_alloc() and free them with125     *  framebuffer_release().126     */127static struct fb_info info;128 129    /*130     * Each one represents the state of the hardware. Most hardware have131     * just one hardware state. These here represent the default state(s).132     */133static struct xxx_par __initdata current_par;134 135/**136 *	xxxfb_open - Optional function. Called when the framebuffer is137 *		     first accessed.138 *	@info: frame buffer structure that represents a single frame buffer139 *	@user: tell us if the userland (value=1) or the console is accessing140 *	       the framebuffer.141 *142 *	This function is the first function called in the framebuffer api.143 *	Usually you don't need to provide this function. The case where it144 *	is used is to change from a text mode hardware state to a graphics145 * 	mode state.146 *147 *	Returns negative errno on error, or zero on success.148 */149static int xxxfb_open(struct fb_info *info, int user)150{151    return 0;152}153 154/**155 *	xxxfb_release - Optional function. Called when the framebuffer156 *			device is closed.157 *	@info: frame buffer structure that represents a single frame buffer158 *	@user: tell us if the userland (value=1) or the console is accessing159 *	       the framebuffer.160 *161 *	Thus function is called when we close /dev/fb or the framebuffer162 *	console system is released. Usually you don't need this function.163 *	The case where it is usually used is to go from a graphics state164 *	to a text mode state.165 *166 *	Returns negative errno on error, or zero on success.167 */168static int xxxfb_release(struct fb_info *info, int user)169{170    return 0;171}172 173/**174 *      xxxfb_check_var - Optional function. Validates a var passed in.175 *      @var: frame buffer variable screen structure176 *      @info: frame buffer structure that represents a single frame buffer177 *178 *	Checks to see if the hardware supports the state requested by179 *	var passed in. This function does not alter the hardware state!!!180 *	This means the data stored in struct fb_info and struct xxx_par do181 *      not change. This includes the var inside of struct fb_info.182 *	Do NOT change these. This function can be called on its own if we183 *	intent to only test a mode and not actually set it. The stuff in184 *	modedb.c is a example of this. If the var passed in is slightly185 *	off by what the hardware can support then we alter the var PASSED in186 *	to what we can do.187 *188 *      For values that are off, this function must round them _up_ to the189 *      next value that is supported by the hardware.  If the value is190 *      greater than the highest value supported by the hardware, then this191 *      function must return -EINVAL.192 *193 *      Exception to the above rule:  Some drivers have a fixed mode, ie,194 *      the hardware is already set at boot up, and cannot be changed.  In195 *      this case, it is more acceptable that this function just return196 *      a copy of the currently working var (info->var). Better is to not197 *      implement this function, as the upper layer will do the copying198 *      of the current var for you.199 *200 *      Note:  This is the only function where the contents of var can be201 *      freely adjusted after the driver has been registered. If you find202 *      that you have code outside of this function that alters the content203 *      of var, then you are doing something wrong.  Note also that the204 *      contents of info->var must be left untouched at all times after205 *      driver registration.206 *207 *	Returns negative errno on error, or zero on success.208 */209static int xxxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)210{211    /* ... */212    return 0;213}214 215/**216 *      xxxfb_set_par - Optional function. Alters the hardware state.217 *      @info: frame buffer structure that represents a single frame buffer218 *219 *	Using the fb_var_screeninfo in fb_info we set the resolution of the220 *	this particular framebuffer. This function alters the par AND the221 *	fb_fix_screeninfo stored in fb_info. It doesn't not alter var in222 *	fb_info since we are using that data. This means we depend on the223 *	data in var inside fb_info to be supported by the hardware.224 *225 *      This function is also used to recover/restore the hardware to a226 *      known working state.227 *228 *	xxxfb_check_var is always called before xxxfb_set_par to ensure that229 *      the contents of var is always valid.230 *231 *	Again if you can't change the resolution you don't need this function.232 *233 *      However, even if your hardware does not support mode changing,234 *      a set_par might be needed to at least initialize the hardware to235 *      a known working state, especially if it came back from another236 *      process that also modifies the same hardware, such as X.237 *238 *      If this is the case, a combination such as the following should work:239 *240 *      static int xxxfb_check_var(struct fb_var_screeninfo *var,241 *                                struct fb_info *info)242 *      {243 *              *var = info->var;244 *              return 0;245 *      }246 *247 *      static int xxxfb_set_par(struct fb_info *info)248 *      {249 *              init your hardware here250 *      }251 *252 *	Returns negative errno on error, or zero on success.253 */254static int xxxfb_set_par(struct fb_info *info)255{256    struct xxx_par *par = info->par;257    /* ... */258    return 0;259}260 261/**262 *  	xxxfb_setcolreg - Optional function. Sets a color register.263 *      @regno: Which register in the CLUT we are programming264 *      @red: The red value which can be up to 16 bits wide265 *	@green: The green value which can be up to 16 bits wide266 *	@blue:  The blue value which can be up to 16 bits wide.267 *	@transp: If supported, the alpha value which can be up to 16 bits wide.268 *      @info: frame buffer info structure269 *270 *  	Set a single color register. The values supplied have a 16 bit271 *  	magnitude which needs to be scaled in this function for the hardware.272 *	Things to take into consideration are how many color registers, if273 *	any, are supported with the current color visual. With truecolor mode274 *	no color palettes are supported. Here a pseudo palette is created275 *	which we store the value in pseudo_palette in struct fb_info. For276 *	pseudocolor mode we have a limited color palette. To deal with this277 *	we can program what color is displayed for a particular pixel value.278 *	DirectColor is similar in that we can program each color field. If279 *	we have a static colormap we don't need to implement this function.280 *281 *	Returns negative errno on error, or zero on success.282 */283static int xxxfb_setcolreg(unsigned regno, unsigned red, unsigned green,284			   unsigned blue, unsigned transp,285			   struct fb_info *info)286{287    if (regno >= 256)  /* no. of hw registers */288       return -EINVAL;289    /*290     * Program hardware... do anything you want with transp291     */292 293    /* grayscale works only partially under directcolor */294    if (info->var.grayscale) {295       /* grayscale = 0.30*R + 0.59*G + 0.11*B */296       red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;297    }298 299    /* Directcolor:300     *   var->{color}.offset contains start of bitfield301     *   var->{color}.length contains length of bitfield302     *   {hardwarespecific} contains width of DAC303     *   pseudo_palette[X] is programmed to (X << red.offset) |304     *                                      (X << green.offset) |305     *                                      (X << blue.offset)306     *   RAMDAC[X] is programmed to (red, green, blue)307     *   color depth = SUM(var->{color}.length)308     *309     * Pseudocolor:310     *    var->{color}.offset is 0 unless the palette index takes less than311     *                        bits_per_pixel bits and is stored in the upper312     *                        bits of the pixel value313     *    var->{color}.length is set so that 1 << length is the number of314     *                        available palette entries315     *    pseudo_palette is not used316     *    RAMDAC[X] is programmed to (red, green, blue)317     *    color depth = var->{color}.length318     *319     * Static pseudocolor:320     *    same as Pseudocolor, but the RAMDAC is not programmed (read-only)321     *322     * Mono01/Mono10:323     *    Has only 2 values, black on white or white on black (fg on bg),324     *    var->{color}.offset is 0325     *    white = (1 << var->{color}.length) - 1, black = 0326     *    pseudo_palette is not used327     *    RAMDAC does not exist328     *    color depth is always 2329     *330     * Truecolor:331     *    does not use RAMDAC (usually has 3 of them).332     *    var->{color}.offset contains start of bitfield333     *    var->{color}.length contains length of bitfield334     *    pseudo_palette is programmed to (red << red.offset) |335     *                                    (green << green.offset) |336     *                                    (blue << blue.offset) |337     *                                    (transp << transp.offset)338     *    RAMDAC does not exist339     *    color depth = SUM(var->{color}.length})340     *341     *  The color depth is used by fbcon for choosing the logo and also342     *  for color palette transformation if color depth < 4343     *344     *  As can be seen from the above, the field bits_per_pixel is _NOT_345     *  a criteria for describing the color visual.346     *347     *  A common mistake is assuming that bits_per_pixel <= 8 is pseudocolor,348     *  and higher than that, true/directcolor.  This is incorrect, one needs349     *  to look at the fix->visual.350     *351     *  Another common mistake is using bits_per_pixel to calculate the color352     *  depth.  The bits_per_pixel field does not directly translate to color353     *  depth. You have to compute for the color depth (using the color354     *  bitfields) and fix->visual as seen above.355     */356 357    /*358     * This is the point where the color is converted to something that359     * is acceptable by the hardware.360     */361#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)362    red = CNVT_TOHW(red, info->var.red.length);363    green = CNVT_TOHW(green, info->var.green.length);364    blue = CNVT_TOHW(blue, info->var.blue.length);365    transp = CNVT_TOHW(transp, info->var.transp.length);366#undef CNVT_TOHW367    /*368     * This is the point where the function feeds the color to the hardware369     * palette after converting the colors to something acceptable by370     * the hardware. Note, only FB_VISUAL_DIRECTCOLOR and371     * FB_VISUAL_PSEUDOCOLOR visuals need to write to the hardware palette.372     * If you have code that writes to the hardware CLUT, and it's not373     * any of the above visuals, then you are doing something wrong.374     */375    if (info->fix.visual == FB_VISUAL_DIRECTCOLOR ||376	info->fix.visual == FB_VISUAL_TRUECOLOR)377	    write_{red|green|blue|transp}_to_clut();378 379    /* This is the point were you need to fill up the contents of380     * info->pseudo_palette. This structure is used _only_ by fbcon, thus381     * it only contains 16 entries to match the number of colors supported382     * by the console. The pseudo_palette is used only if the visual is383     * in directcolor or truecolor mode.  With other visuals, the384     * pseudo_palette is not used. (This might change in the future.)385     *386     * The contents of the pseudo_palette is in raw pixel format.  Ie, each387     * entry can be written directly to the framebuffer without any conversion.388     * The pseudo_palette is (void *).  However, if using the generic389     * drawing functions (cfb_imageblit, cfb_fillrect), the pseudo_palette390     * must be casted to (u32 *) _regardless_ of the bits per pixel. If the391     * driver is using its own drawing functions, then it can use whatever392     * size it wants.393     */394    if (info->fix.visual == FB_VISUAL_TRUECOLOR ||395	info->fix.visual == FB_VISUAL_DIRECTCOLOR) {396	    u32 v;397 398	    if (regno >= 16)399		    return -EINVAL;400 401	    v = (red << info->var.red.offset) |402		    (green << info->var.green.offset) |403		    (blue << info->var.blue.offset) |404		    (transp << info->var.transp.offset);405 406	    ((u32*)(info->pseudo_palette))[regno] = v;407    }408 409    /* ... */410    return 0;411}412 413/**414 *      xxxfb_pan_display - NOT a required function. Pans the display.415 *      @var: frame buffer variable screen structure416 *      @info: frame buffer structure that represents a single frame buffer417 *418 *	Pan (or wrap, depending on the `vmode' field) the display using the419 *  	`xoffset' and `yoffset' fields of the `var' structure.420 *  	If the values don't fit, return -EINVAL.421 *422 *      Returns negative errno on error, or zero on success.423 */424static int xxxfb_pan_display(struct fb_var_screeninfo *var,425			     struct fb_info *info)426{427    /*428     * If your hardware does not support panning, _do_ _not_ implement this429     * function. Creating a dummy function will just confuse user apps.430     */431 432    /*433     * Note that even if this function is fully functional, a setting of434     * 0 in both xpanstep and ypanstep means that this function will never435     * get called.436     */437 438    /* ... */439    return 0;440}441 442/**443 *      xxxfb_blank - NOT a required function. Blanks the display.444 *      @blank_mode: the blank mode we want.445 *      @info: frame buffer structure that represents a single frame buffer446 *447 *      Blank the screen if blank_mode != FB_BLANK_UNBLANK, else unblank.448 *      Return 0 if blanking succeeded, != 0 if un-/blanking failed due to449 *      e.g. a video mode which doesn't support it.450 *451 *      Implements VESA suspend and powerdown modes on hardware that supports452 *      disabling hsync/vsync:453 *454 *      FB_BLANK_NORMAL = display is blanked, syncs are on.455 *      FB_BLANK_HSYNC_SUSPEND = hsync off456 *      FB_BLANK_VSYNC_SUSPEND = vsync off457 *      FB_BLANK_POWERDOWN =  hsync and vsync off458 *459 *      If implementing this function, at least support FB_BLANK_UNBLANK.460 *      Return !0 for any modes that are unimplemented.461 *462 */463static int xxxfb_blank(int blank_mode, struct fb_info *info)464{465    /* ... */466    return 0;467}468 469/* ------------ Accelerated Functions --------------------- */470 471/*472 * We provide our own functions if we have hardware acceleration473 * or non packed pixel format layouts. If we have no hardware474 * acceleration, we can use a generic unaccelerated function. If using475 * a pack pixel format just use the functions in cfb_*.c. Each file476 * has one of the three different accel functions we support.477 */478 479/**480 *      xxxfb_fillrect - REQUIRED function. Can use generic routines if481 *		 	 non acclerated hardware and packed pixel based.482 *			 Draws a rectangle on the screen.483 *484 *      @info: frame buffer structure that represents a single frame buffer485 *	@region: The structure representing the rectangular region we486 *		 wish to draw to.487 *488 *	This drawing operation places/removes a retangle on the screen489 *	depending on the rastering operation with the value of color which490 *	is in the current color depth format.491 */492void xxxfb_fillrect(struct fb_info *p, const struct fb_fillrect *region)493{494/*	Meaning of struct fb_fillrect495 *496 *	@dx: The x and y corrdinates of the upper left hand corner of the497 *	@dy: area we want to draw to.498 *	@width: How wide the rectangle is we want to draw.499 *	@height: How tall the rectangle is we want to draw.500 *	@color:	The color to fill in the rectangle with.501 *	@rop: The raster operation. We can draw the rectangle with a COPY502 *	      of XOR which provides erasing effect.503 */504}505 506/**507 *      xxxfb_copyarea - REQUIRED function. Can use generic routines if508 *                       non acclerated hardware and packed pixel based.509 *                       Copies one area of the screen to another area.510 *511 *      @info: frame buffer structure that represents a single frame buffer512 *      @area: Structure providing the data to copy the framebuffer contents513 *	       from one region to another.514 *515 *      This drawing operation copies a rectangular area from one area of the516 *	screen to another area.517 */518void xxxfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)519{520/*521 *      @dx: The x and y coordinates of the upper left hand corner of the522 *	@dy: destination area on the screen.523 *      @width: How wide the rectangle is we want to copy.524 *      @height: How tall the rectangle is we want to copy.525 *      @sx: The x and y coordinates of the upper left hand corner of the526 *      @sy: source area on the screen.527 */528}529 530 531/**532 *      xxxfb_imageblit - REQUIRED function. Can use generic routines if533 *                        non acclerated hardware and packed pixel based.534 *                        Copies a image from system memory to the screen.535 *536 *      @info: frame buffer structure that represents a single frame buffer537 *	@image:	structure defining the image.538 *539 *      This drawing operation draws a image on the screen. It can be a540 *	mono image (needed for font handling) or a color image (needed for541 *	tux).542 */543void xxxfb_imageblit(struct fb_info *p, const struct fb_image *image)544{545/*546 *      @dx: The x and y coordinates of the upper left hand corner of the547 *	@dy: destination area to place the image on the screen.548 *      @width: How wide the image is we want to copy.549 *      @height: How tall the image is we want to copy.550 *      @fg_color: For mono bitmap images this is color data for551 *      @bg_color: the foreground and background of the image to552 *		   write directly to the frmaebuffer.553 *	@depth:	How many bits represent a single pixel for this image.554 *	@data: The actual data used to construct the image on the display.555 *	@cmap: The colormap used for color images.556 */557 558/*559 * The generic function, cfb_imageblit, expects that the bitmap scanlines are560 * padded to the next byte.  Most hardware accelerators may require padding to561 * the next u16 or the next u32.  If that is the case, the driver can specify562 * this by setting info->pixmap.scan_align = 2 or 4.  See a more563 * comprehensive description of the pixmap below.564 */565}566 567/**568 *	xxxfb_cursor - 	OPTIONAL. If your hardware lacks support569 *			for a cursor, leave this field NULL.570 *571 *      @info: frame buffer structure that represents a single frame buffer572 *	@cursor: structure defining the cursor to draw.573 *574 *      This operation is used to set or alter the properities of the575 *	cursor.576 *577 *	Returns negative errno on error, or zero on success.578 */579int xxxfb_cursor(struct fb_info *info, struct fb_cursor *cursor)580{581/*582 *      @set: 	Which fields we are altering in struct fb_cursor583 *	@enable: Disable or enable the cursor584 *      @rop: 	The bit operation we want to do.585 *      @mask:  This is the cursor mask bitmap.586 *      @dest:  A image of the area we are going to display the cursor.587 *		Used internally by the driver.588 *      @hot:	The hot spot.589 *	@image:	The actual data for the cursor image.590 *591 *      NOTES ON FLAGS (cursor->set):592 *593 *      FB_CUR_SETIMAGE - the cursor image has changed (cursor->image.data)594 *      FB_CUR_SETPOS   - the cursor position has changed (cursor->image.dx|dy)595 *      FB_CUR_SETHOT   - the cursor hot spot has changed (cursor->hot.dx|dy)596 *      FB_CUR_SETCMAP  - the cursor colors has changed (cursor->fg_color|bg_color)597 *      FB_CUR_SETSHAPE - the cursor bitmask has changed (cursor->mask)598 *      FB_CUR_SETSIZE  - the cursor size has changed (cursor->width|height)599 *      FB_CUR_SETALL   - everything has changed600 *601 *      NOTES ON ROPs (cursor->rop, Raster Operation)602 *603 *      ROP_XOR         - cursor->image.data XOR cursor->mask604 *      ROP_COPY        - curosr->image.data AND cursor->mask605 *606 *      OTHER NOTES:607 *608 *      - fbcon only supports a 2-color cursor (cursor->image.depth = 1)609 *      - The fb_cursor structure, @cursor, _will_ always contain valid610 *        fields, whether any particular bitfields in cursor->set is set611 *        or not.612 */613}614 615/**616 *	xxxfb_sync - NOT a required function. Normally the accel engine617 *		     for a graphics card take a specific amount of time.618 *		     Often we have to wait for the accelerator to finish619 *		     its operation before we can write to the framebuffer620 *		     so we can have consistent display output.621 *622 *      @info: frame buffer structure that represents a single frame buffer623 *624 *      If the driver has implemented its own hardware-based drawing function,625 *      implementing this function is highly recommended.626 */627int xxxfb_sync(struct fb_info *info)628{629	return 0;630}631 632    /*633     *  Frame buffer operations634     */635 636static const struct fb_ops xxxfb_ops = {637	.owner		= THIS_MODULE,638	.fb_open	= xxxfb_open,639	.fb_read	= xxxfb_read,640	.fb_write	= xxxfb_write,641	.fb_release	= xxxfb_release,642	.fb_check_var	= xxxfb_check_var,643	.fb_set_par	= xxxfb_set_par,644	.fb_setcolreg	= xxxfb_setcolreg,645	.fb_blank	= xxxfb_blank,646	.fb_pan_display	= xxxfb_pan_display,647	.fb_fillrect	= xxxfb_fillrect, 	/* Needed !!! */648	.fb_copyarea	= xxxfb_copyarea,	/* Needed !!! */649	.fb_imageblit	= xxxfb_imageblit,	/* Needed !!! */650	.fb_cursor	= xxxfb_cursor,		/* Optional !!! */651	.fb_sync	= xxxfb_sync,652	.fb_ioctl	= xxxfb_ioctl,653	.fb_mmap	= xxxfb_mmap,654};655 656/* ------------------------------------------------------------------------- */657 658    /*659     *  Initialization660     */661 662/* static int __init xxfb_probe (struct platform_device *pdev) -- for platform devs */663static int xxxfb_probe(struct pci_dev *dev, const struct pci_device_id *ent)664{665    struct fb_info *info;666    struct xxx_par *par;667    struct device *device = &dev->dev; /* or &pdev->dev */668    int cmap_len, retval;669 670    /*671     * Remove firmware-based drivers that create resource conflicts.672     */673    retval = aperture_remove_conflicting_pci_devices(pdev, "xxxfb");674    if (retval)675	    return retval;676 677    /*678     * Dynamically allocate info and par679     */680    info = framebuffer_alloc(sizeof(struct xxx_par), device);681 682    if (!info) {683	    /* goto error path */684    }685 686    par = info->par;687 688    /*689     * Here we set the screen_base to the virtual memory address690     * for the framebuffer. Usually we obtain the resource address691     * from the bus layer and then translate it to virtual memory692     * space via ioremap. Consult ioport.h.693     */694    info->screen_base = framebuffer_virtual_memory;695    info->fbops = &xxxfb_ops;696    info->fix = xxxfb_fix;697    info->pseudo_palette = pseudo_palette; /* The pseudopalette is an698					    * 16-member array699					    */700    /*701     * Set up flags to indicate what sort of acceleration your702     * driver can provide (pan/wrap/copyarea/etc.) and whether it703     * is a module -- see FBINFO_* in include/linux/fb.h704     *705     * If your hardware can support any of the hardware accelerated functions706     * fbcon performance will improve if info->flags is set properly.707     *708     * FBINFO_HWACCEL_COPYAREA - hardware moves709     * FBINFO_HWACCEL_FILLRECT - hardware fills710     * FBINFO_HWACCEL_IMAGEBLIT - hardware mono->color expansion711     * FBINFO_HWACCEL_YPAN - hardware can pan display in y-axis712     * FBINFO_HWACCEL_YWRAP - hardware can wrap display in y-axis713     * FBINFO_HWACCEL_DISABLED - supports hardware accels, but disabled714     * FBINFO_READS_FAST - if set, prefer moves over mono->color expansion715     * FBINFO_MISC_TILEBLITTING - hardware can do tile blits716     *717     * NOTE: These are for fbcon use only.718     */719    info->flags = 0;720 721/********************* This stage is optional ******************************/722     /*723     * The struct pixmap is a scratch pad for the drawing functions. This724     * is where the monochrome bitmap is constructed by the higher layers725     * and then passed to the accelerator.  For drivers that uses726     * cfb_imageblit, you can skip this part.  For those that have a more727     * rigorous requirement, this stage is needed728     */729 730    /* PIXMAP_SIZE should be small enough to optimize drawing, but not731     * large enough that memory is wasted.  A safe size is732     * (max_xres * max_font_height/8). max_xres is driver dependent,733     * max_font_height is 32.734     */735    info->pixmap.addr = kmalloc(PIXMAP_SIZE, GFP_KERNEL);736    if (!info->pixmap.addr) {737	    /* goto error */738    }739 740    info->pixmap.size = PIXMAP_SIZE;741 742    /*743     * FB_PIXMAP_SYSTEM - memory is in system ram744     * FB_PIXMAP_IO     - memory is iomapped745     * FB_PIXMAP_SYNC   - if set, will call fb_sync() per access to pixmap,746     *                    usually if FB_PIXMAP_IO is set.747     *748     * Currently, FB_PIXMAP_IO is unimplemented.749     */750    info->pixmap.flags = FB_PIXMAP_SYSTEM;751 752    /*753     * scan_align is the number of padding for each scanline.  It is in bytes.754     * Thus for accelerators that need padding to the next u32, put 4 here.755     */756    info->pixmap.scan_align = 4;757 758    /*759     * buf_align is the amount to be padded for the buffer. For example,760     * the i810fb needs a scan_align of 2 but expects it to be fed with761     * dwords, so a buf_align = 4 is required.762     */763    info->pixmap.buf_align = 4;764 765    /* access_align is how many bits can be accessed from the framebuffer766     * ie. some epson cards allow 16-bit access only.  Most drivers will767     * be safe with u32 here.768     *769     * NOTE: This field is currently unused.770     */771    info->pixmap.access_align = 32;772/***************************** End optional stage ***************************/773 774    /*775     * This should give a reasonable default video mode. The following is776     * done when we can set a video mode.777     */778    if (!mode_option)779	mode_option = "640x480@60";780 781    retval = fb_find_mode(&info->var, info, mode_option, NULL, 0, NULL, 8);782 783    if (!retval || retval == 4)784	return -EINVAL;785 786    /* This has to be done! */787    if (fb_alloc_cmap(&info->cmap, cmap_len, 0))788	return -ENOMEM;789 790    /*791     * The following is done in the case of having hardware with a static792     * mode. If we are setting the mode ourselves we don't call this.793     */794    info->var = xxxfb_var;795 796    /*797     * For drivers that can...798     */799    xxxfb_check_var(&info->var, info);800 801    /*802     * Does a call to fb_set_par() before register_framebuffer needed?  This803     * will depend on you and the hardware.  If you are sure that your driver804     * is the only device in the system, a call to fb_set_par() is safe.805     *806     * Hardware in x86 systems has a VGA core.  Calling set_par() at this807     * point will corrupt the VGA console, so it might be safer to skip a808     * call to set_par here and just allow fbcon to do it for you.809     */810    /* xxxfb_set_par(info); */811 812    if (register_framebuffer(info) < 0) {813	fb_dealloc_cmap(&info->cmap);814	return -EINVAL;815    }816    fb_info(info, "%s frame buffer device\n", info->fix.id);817    pci_set_drvdata(dev, info); /* or platform_set_drvdata(pdev, info) */818    return 0;819}820 821    /*822     *  Cleanup823     */824/* static void xxxfb_remove(struct platform_device *pdev) */825static void xxxfb_remove(struct pci_dev *dev)826{827	struct fb_info *info = pci_get_drvdata(dev);828	/* or platform_get_drvdata(pdev); */829 830	if (info) {831		unregister_framebuffer(info);832		fb_dealloc_cmap(&info->cmap);833		/* ... */834		framebuffer_release(info);835	}836}837 838#ifdef CONFIG_PCI839#ifdef CONFIG_PM840/**841 *	xxxfb_suspend - Optional but recommended function. Suspend the device.842 *	@dev: PCI device843 *	@msg: the suspend event code.844 *845 *      See Documentation/driver-api/pm/devices.rst for more information846 */847static int xxxfb_suspend(struct device *dev)848{849	struct fb_info *info = dev_get_drvdata(dev);850	struct xxxfb_par *par = info->par;851 852	/* suspend here */853	return 0;854}855 856/**857 *	xxxfb_resume - Optional but recommended function. Resume the device.858 *	@dev: PCI device859 *860 *      See Documentation/driver-api/pm/devices.rst for more information861 */862static int xxxfb_resume(struct device *dev)863{864	struct fb_info *info = dev_get_drvdata(dev);865	struct xxxfb_par *par = info->par;866 867	/* resume here */868	return 0;869}870#else871#define xxxfb_suspend NULL872#define xxxfb_resume NULL873#endif /* CONFIG_PM */874 875static const struct pci_device_id xxxfb_id_table[] = {876	{ PCI_VENDOR_ID_XXX, PCI_DEVICE_ID_XXX,877	  PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY << 16,878	  PCI_CLASS_MASK, 0 },879	{ 0, }880};881 882static SIMPLE_DEV_PM_OPS(xxxfb_pm_ops, xxxfb_suspend, xxxfb_resume);883 884/* For PCI drivers */885static struct pci_driver xxxfb_driver = {886	.name =		"xxxfb",887	.id_table =	xxxfb_id_table,888	.probe =	xxxfb_probe,889	.remove =	xxxfb_remove,890	.driver.pm =	xxxfb_pm_ops, /* optional but recommended */891};892 893MODULE_DEVICE_TABLE(pci, xxxfb_id_table);894 895static int __init xxxfb_init(void)896{897	/*898	 *  For kernel boot options (in 'video=xxxfb:<options>' format)899	 */900#ifndef MODULE901	char *option = NULL;902 903	if (fb_get_options("xxxfb", &option))904		return -ENODEV;905	xxxfb_setup(option);906#endif907 908	return pci_register_driver(&xxxfb_driver);909}910 911static void __exit xxxfb_exit(void)912{913	pci_unregister_driver(&xxxfb_driver);914}915#else /* non PCI, platform drivers */916#include <linux/platform_device.h>917/* for platform devices */918 919#ifdef CONFIG_PM920/**921 *	xxxfb_suspend - Optional but recommended function. Suspend the device.922 *	@dev: platform device923 *	@msg: the suspend event code.924 *925 *      See Documentation/driver-api/pm/devices.rst for more information926 */927static int xxxfb_suspend(struct platform_device *dev, pm_message_t msg)928{929	struct fb_info *info = platform_get_drvdata(dev);930	struct xxxfb_par *par = info->par;931 932	/* suspend here */933	return 0;934}935 936/**937 *	xxxfb_resume - Optional but recommended function. Resume the device.938 *	@dev: platform device939 *940 *      See Documentation/driver-api/pm/devices.rst for more information941 */942static int xxxfb_resume(struct platform_dev *dev)943{944	struct fb_info *info = platform_get_drvdata(dev);945	struct xxxfb_par *par = info->par;946 947	/* resume here */948	return 0;949}950#else951#define xxxfb_suspend NULL952#define xxxfb_resume NULL953#endif /* CONFIG_PM */954 955static struct platform_device_driver xxxfb_driver = {956	.probe = xxxfb_probe,957	.remove = xxxfb_remove,958	.suspend = xxxfb_suspend, /* optional but recommended */959	.resume = xxxfb_resume,   /* optional but recommended */960	.driver = {961		.name = "xxxfb",962	},963};964 965static struct platform_device *xxxfb_device;966 967#ifndef MODULE968    /*969     *  Setup970     */971 972/*973 * Only necessary if your driver takes special options,974 * otherwise we fall back on the generic fb_setup().975 */976static int __init xxxfb_setup(char *options)977{978    /* Parse user specified options (`video=xxxfb:') */979}980#endif /* MODULE */981 982static int __init xxxfb_init(void)983{984	int ret;985	/*986	 *  For kernel boot options (in 'video=xxxfb:<options>' format)987	 */988#ifndef MODULE989	char *option = NULL;990#endif991 992	if (fb_modesetting_disabled("xxxfb"))993		return -ENODEV;994 995#ifndef MODULE996	if (fb_get_options("xxxfb", &option))997		return -ENODEV;998	xxxfb_setup(option);999#endif1000	ret = platform_driver_register(&xxxfb_driver);1001 1002	if (!ret) {1003		xxxfb_device = platform_device_register_simple("xxxfb", 0,1004								NULL, 0);1005 1006		if (IS_ERR(xxxfb_device)) {1007			platform_driver_unregister(&xxxfb_driver);1008			ret = PTR_ERR(xxxfb_device);1009		}1010	}1011 1012	return ret;1013}1014 1015static void __exit xxxfb_exit(void)1016{1017	platform_device_unregister(xxxfb_device);1018	platform_driver_unregister(&xxxfb_driver);1019}1020#endif /* CONFIG_PCI */1021 1022/* ------------------------------------------------------------------------- */1023 1024 1025    /*1026     *  Modularization1027     */1028 1029module_init(xxxfb_init);1030module_exit(xxxfb_exit);1031 1032MODULE_LICENSE("GPL");1033