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[cris-mirror.git] / drivers / video / skeletonfb.c
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1 /*
2 * linux/drivers/video/skeletonfb.c -- Skeleton for a frame buffer device
4 * Modified to new api Jan 2001 by James Simmons (jsimmons@transvirtual.com)
6 * Created 28 Dec 1997 by Geert Uytterhoeven
9 * I have started rewriting this driver as a example of the upcoming new API
10 * The primary goal is to remove the console code from fbdev and place it
11 * into fbcon.c. This reduces the code and makes writing a new fbdev driver
12 * easy since the author doesn't need to worry about console internals. It
13 * also allows the ability to run fbdev without a console/tty system on top
14 * of it.
16 * First the roles of struct fb_info and struct display have changed. Struct
17 * display will go away. The way the new framebuffer console code will
18 * work is that it will act to translate data about the tty/console in
19 * struct vc_data to data in a device independent way in struct fb_info. Then
20 * various functions in struct fb_ops will be called to store the device
21 * dependent state in the par field in struct fb_info and to change the
22 * hardware to that state. This allows a very clean separation of the fbdev
23 * layer from the console layer. It also allows one to use fbdev on its own
24 * which is a bounus for embedded devices. The reason this approach works is
25 * for each framebuffer device when used as a tty/console device is allocated
26 * a set of virtual terminals to it. Only one virtual terminal can be active
27 * per framebuffer device. We already have all the data we need in struct
28 * vc_data so why store a bunch of colormaps and other fbdev specific data
29 * per virtual terminal.
31 * As you can see doing this makes the con parameter pretty much useless
32 * for struct fb_ops functions, as it should be. Also having struct
33 * fb_var_screeninfo and other data in fb_info pretty much eliminates the
34 * need for get_fix and get_var. Once all drivers use the fix, var, and cmap
35 * fbcon can be written around these fields. This will also eliminate the
36 * need to regenerate struct fb_var_screeninfo, struct fb_fix_screeninfo
37 * struct fb_cmap every time get_var, get_fix, get_cmap functions are called
38 * as many drivers do now.
40 * This file is subject to the terms and conditions of the GNU General Public
41 * License. See the file COPYING in the main directory of this archive for
42 * more details.
45 #include <linux/module.h>
46 #include <linux/kernel.h>
47 #include <linux/errno.h>
48 #include <linux/string.h>
49 #include <linux/mm.h>
50 #include <linux/slab.h>
51 #include <linux/delay.h>
52 #include <linux/fb.h>
53 #include <linux/init.h>
54 #include <linux/pci.h>
57 * This is just simple sample code.
59 * No warranty that it actually compiles.
60 * Even less warranty that it actually works :-)
64 * Driver data
66 static char *mode_option;
69 * If your driver supports multiple boards, you should make the
70 * below data types arrays, or allocate them dynamically (using kmalloc()).
71 */
73 /*
74 * This structure defines the hardware state of the graphics card. Normally
75 * you place this in a header file in linux/include/video. This file usually
76 * also includes register information. That allows other driver subsystems
77 * and userland applications the ability to use the same header file to
78 * avoid duplicate work and easy porting of software.
80 struct xxx_par;
83 * Here we define the default structs fb_fix_screeninfo and fb_var_screeninfo
84 * if we don't use modedb. If we do use modedb see xxxfb_init how to use it
85 * to get a fb_var_screeninfo. Otherwise define a default var as well.
87 static struct fb_fix_screeninfo xxxfb_fix = {
88 .id = "FB's name",
89 .type = FB_TYPE_PACKED_PIXELS,
90 .visual = FB_VISUAL_PSEUDOCOLOR,
91 .xpanstep = 1,
92 .ypanstep = 1,
93 .ywrapstep = 1,
94 .accel = FB_ACCEL_NONE,
98 * Modern graphical hardware not only supports pipelines but some
99 * also support multiple monitors where each display can have its
100 * its own unique data. In this case each display could be
101 * represented by a separate framebuffer device thus a separate
102 * struct fb_info. Now the struct xxx_par represents the graphics
103 * hardware state thus only one exist per card. In this case the
104 * struct xxx_par for each graphics card would be shared between
105 * every struct fb_info that represents a framebuffer on that card.
106 * This allows when one display changes it video resolution (info->var)
107 * the other displays know instantly. Each display can always be
108 * aware of the entire hardware state that affects it because they share
109 * the same xxx_par struct. The other side of the coin is multiple
110 * graphics cards that pass data around until it is finally displayed
111 * on one monitor. Such examples are the voodoo 1 cards and high end
112 * NUMA graphics servers. For this case we have a bunch of pars, each
113 * one that represents a graphics state, that belong to one struct
114 * fb_info. Their you would want to have *par point to a array of device
115 * states and have each struct fb_ops function deal with all those
116 * states. I hope this covers every possible hardware design. If not
117 * feel free to send your ideas at jsimmons@users.sf.net
121 * If your driver supports multiple boards or it supports multiple
122 * framebuffers, you should make these arrays, or allocate them
123 * dynamically using framebuffer_alloc() and free them with
124 * framebuffer_release().
126 static struct fb_info info;
129 * Each one represents the state of the hardware. Most hardware have
130 * just one hardware state. These here represent the default state(s).
132 static struct xxx_par __initdata current_par;
134 int xxxfb_init(void);
137 * xxxfb_open - Optional function. Called when the framebuffer is
138 * first accessed.
139 * @info: frame buffer structure that represents a single frame buffer
140 * @user: tell us if the userland (value=1) or the console is accessing
141 * the framebuffer.
143 * This function is the first function called in the framebuffer api.
144 * Usually you don't need to provide this function. The case where it
145 * is used is to change from a text mode hardware state to a graphics
146 * mode state.
148 * Returns negative errno on error, or zero on success.
150 static int xxxfb_open(struct fb_info *info, int user)
152 return 0;
156 * xxxfb_release - Optional function. Called when the framebuffer
157 * device is closed.
158 * @info: frame buffer structure that represents a single frame buffer
159 * @user: tell us if the userland (value=1) or the console is accessing
160 * the framebuffer.
162 * Thus function is called when we close /dev/fb or the framebuffer
163 * console system is released. Usually you don't need this function.
164 * The case where it is usually used is to go from a graphics state
165 * to a text mode state.
167 * Returns negative errno on error, or zero on success.
169 static int xxxfb_release(struct fb_info *info, int user)
171 return 0;
175 * xxxfb_check_var - Optional function. Validates a var passed in.
176 * @var: frame buffer variable screen structure
177 * @info: frame buffer structure that represents a single frame buffer
179 * Checks to see if the hardware supports the state requested by
180 * var passed in. This function does not alter the hardware state!!!
181 * This means the data stored in struct fb_info and struct xxx_par do
182 * not change. This includes the var inside of struct fb_info.
183 * Do NOT change these. This function can be called on its own if we
184 * intent to only test a mode and not actually set it. The stuff in
185 * modedb.c is a example of this. If the var passed in is slightly
186 * off by what the hardware can support then we alter the var PASSED in
187 * to what we can do.
189 * For values that are off, this function must round them _up_ to the
190 * next value that is supported by the hardware. If the value is
191 * greater than the highest value supported by the hardware, then this
192 * function must return -EINVAL.
194 * Exception to the above rule: Some drivers have a fixed mode, ie,
195 * the hardware is already set at boot up, and cannot be changed. In
196 * this case, it is more acceptable that this function just return
197 * a copy of the currently working var (info->var). Better is to not
198 * implement this function, as the upper layer will do the copying
199 * of the current var for you.
201 * Note: This is the only function where the contents of var can be
202 * freely adjusted after the driver has been registered. If you find
203 * that you have code outside of this function that alters the content
204 * of var, then you are doing something wrong. Note also that the
205 * contents of info->var must be left untouched at all times after
206 * driver registration.
208 * Returns negative errno on error, or zero on success.
210 static int xxxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
212 /* ... */
213 return 0;
217 * xxxfb_set_par - Optional function. Alters the hardware state.
218 * @info: frame buffer structure that represents a single frame buffer
220 * Using the fb_var_screeninfo in fb_info we set the resolution of the
221 * this particular framebuffer. This function alters the par AND the
222 * fb_fix_screeninfo stored in fb_info. It doesn't not alter var in
223 * fb_info since we are using that data. This means we depend on the
224 * data in var inside fb_info to be supported by the hardware.
226 * This function is also used to recover/restore the hardware to a
227 * known working state.
229 * xxxfb_check_var is always called before xxxfb_set_par to ensure that
230 * the contents of var is always valid.
232 * Again if you can't change the resolution you don't need this function.
234 * However, even if your hardware does not support mode changing,
235 * a set_par might be needed to at least initialize the hardware to
236 * a known working state, especially if it came back from another
237 * process that also modifies the same hardware, such as X.
239 * If this is the case, a combination such as the following should work:
241 * static int xxxfb_check_var(struct fb_var_screeninfo *var,
242 * struct fb_info *info)
244 * *var = info->var;
245 * return 0;
248 * static int xxxfb_set_par(struct fb_info *info)
250 * init your hardware here
253 * Returns negative errno on error, or zero on success.
255 static int xxxfb_set_par(struct fb_info *info)
257 struct xxx_par *par = info->par;
258 /* ... */
259 return 0;
263 * xxxfb_setcolreg - Optional function. Sets a color register.
264 * @regno: Which register in the CLUT we are programming
265 * @red: The red value which can be up to 16 bits wide
266 * @green: The green value which can be up to 16 bits wide
267 * @blue: The blue value which can be up to 16 bits wide.
268 * @transp: If supported, the alpha value which can be up to 16 bits wide.
269 * @info: frame buffer info structure
271 * Set a single color register. The values supplied have a 16 bit
272 * magnitude which needs to be scaled in this function for the hardware.
273 * Things to take into consideration are how many color registers, if
274 * any, are supported with the current color visual. With truecolor mode
275 * no color palettes are supported. Here a pseudo palette is created
276 * which we store the value in pseudo_palette in struct fb_info. For
277 * pseudocolor mode we have a limited color palette. To deal with this
278 * we can program what color is displayed for a particular pixel value.
279 * DirectColor is similar in that we can program each color field. If
280 * we have a static colormap we don't need to implement this function.
282 * Returns negative errno on error, or zero on success.
284 static int xxxfb_setcolreg(unsigned regno, unsigned red, unsigned green,
285 unsigned blue, unsigned transp,
286 struct fb_info *info)
288 if (regno >= 256) /* no. of hw registers */
289 return -EINVAL;
291 * Program hardware... do anything you want with transp
294 /* grayscale works only partially under directcolor */
295 if (info->var.grayscale) {
296 /* grayscale = 0.30*R + 0.59*G + 0.11*B */
297 red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
300 /* Directcolor:
301 * var->{color}.offset contains start of bitfield
302 * var->{color}.length contains length of bitfield
303 * {hardwarespecific} contains width of DAC
304 * pseudo_palette[X] is programmed to (X << red.offset) |
305 * (X << green.offset) |
306 * (X << blue.offset)
307 * RAMDAC[X] is programmed to (red, green, blue)
308 * color depth = SUM(var->{color}.length)
310 * Pseudocolor:
311 * var->{color}.offset is 0 unless the palette index takes less than
312 * bits_per_pixel bits and is stored in the upper
313 * bits of the pixel value
314 * var->{color}.length is set so that 1 << length is the number of
315 * available palette entries
316 * pseudo_palette is not used
317 * RAMDAC[X] is programmed to (red, green, blue)
318 * color depth = var->{color}.length
320 * Static pseudocolor:
321 * same as Pseudocolor, but the RAMDAC is not programmed (read-only)
323 * Mono01/Mono10:
324 * Has only 2 values, black on white or white on black (fg on bg),
325 * var->{color}.offset is 0
326 * white = (1 << var->{color}.length) - 1, black = 0
327 * pseudo_palette is not used
328 * RAMDAC does not exist
329 * color depth is always 2
331 * Truecolor:
332 * does not use RAMDAC (usually has 3 of them).
333 * var->{color}.offset contains start of bitfield
334 * var->{color}.length contains length of bitfield
335 * pseudo_palette is programmed to (red << red.offset) |
336 * (green << green.offset) |
337 * (blue << blue.offset) |
338 * (transp << transp.offset)
339 * RAMDAC does not exist
340 * color depth = SUM(var->{color}.length})
342 * The color depth is used by fbcon for choosing the logo and also
343 * for color palette transformation if color depth < 4
345 * As can be seen from the above, the field bits_per_pixel is _NOT_
346 * a criteria for describing the color visual.
348 * A common mistake is assuming that bits_per_pixel <= 8 is pseudocolor,
349 * and higher than that, true/directcolor. This is incorrect, one needs
350 * to look at the fix->visual.
352 * Another common mistake is using bits_per_pixel to calculate the color
353 * depth. The bits_per_pixel field does not directly translate to color
354 * depth. You have to compute for the color depth (using the color
355 * bitfields) and fix->visual as seen above.
359 * This is the point where the color is converted to something that
360 * is acceptable by the hardware.
362 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
363 red = CNVT_TOHW(red, info->var.red.length);
364 green = CNVT_TOHW(green, info->var.green.length);
365 blue = CNVT_TOHW(blue, info->var.blue.length);
366 transp = CNVT_TOHW(transp, info->var.transp.length);
367 #undef CNVT_TOHW
369 * This is the point where the function feeds the color to the hardware
370 * palette after converting the colors to something acceptable by
371 * the hardware. Note, only FB_VISUAL_DIRECTCOLOR and
372 * FB_VISUAL_PSEUDOCOLOR visuals need to write to the hardware palette.
373 * If you have code that writes to the hardware CLUT, and it's not
374 * any of the above visuals, then you are doing something wrong.
376 if (info->fix.visual == FB_VISUAL_DIRECTCOLOR ||
377 info->fix.visual == FB_VISUAL_TRUECOLOR)
378 write_{red|green|blue|transp}_to_clut();
380 /* This is the point were you need to fill up the contents of
381 * info->pseudo_palette. This structure is used _only_ by fbcon, thus
382 * it only contains 16 entries to match the number of colors supported
383 * by the console. The pseudo_palette is used only if the visual is
384 * in directcolor or truecolor mode. With other visuals, the
385 * pseudo_palette is not used. (This might change in the future.)
387 * The contents of the pseudo_palette is in raw pixel format. Ie, each
388 * entry can be written directly to the framebuffer without any conversion.
389 * The pseudo_palette is (void *). However, if using the generic
390 * drawing functions (cfb_imageblit, cfb_fillrect), the pseudo_palette
391 * must be casted to (u32 *) _regardless_ of the bits per pixel. If the
392 * driver is using its own drawing functions, then it can use whatever
393 * size it wants.
395 if (info->fix.visual == FB_VISUAL_TRUECOLOR ||
396 info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
397 u32 v;
399 if (regno >= 16)
400 return -EINVAL;
402 v = (red << info->var.red.offset) |
403 (green << info->var.green.offset) |
404 (blue << info->var.blue.offset) |
405 (transp << info->var.transp.offset);
407 ((u32*)(info->pseudo_palette))[regno] = v;
410 /* ... */
411 return 0;
415 * xxxfb_pan_display - NOT a required function. Pans the display.
416 * @var: frame buffer variable screen structure
417 * @info: frame buffer structure that represents a single frame buffer
419 * Pan (or wrap, depending on the `vmode' field) the display using the
420 * `xoffset' and `yoffset' fields of the `var' structure.
421 * If the values don't fit, return -EINVAL.
423 * Returns negative errno on error, or zero on success.
425 static int xxxfb_pan_display(struct fb_var_screeninfo *var,
426 struct fb_info *info)
429 * If your hardware does not support panning, _do_ _not_ implement this
430 * function. Creating a dummy function will just confuse user apps.
434 * Note that even if this function is fully functional, a setting of
435 * 0 in both xpanstep and ypanstep means that this function will never
436 * get called.
439 /* ... */
440 return 0;
444 * xxxfb_blank - NOT a required function. Blanks the display.
445 * @blank_mode: the blank mode we want.
446 * @info: frame buffer structure that represents a single frame buffer
448 * Blank the screen if blank_mode != FB_BLANK_UNBLANK, else unblank.
449 * Return 0 if blanking succeeded, != 0 if un-/blanking failed due to
450 * e.g. a video mode which doesn't support it.
452 * Implements VESA suspend and powerdown modes on hardware that supports
453 * disabling hsync/vsync:
455 * FB_BLANK_NORMAL = display is blanked, syncs are on.
456 * FB_BLANK_HSYNC_SUSPEND = hsync off
457 * FB_BLANK_VSYNC_SUSPEND = vsync off
458 * FB_BLANK_POWERDOWN = hsync and vsync off
460 * If implementing this function, at least support FB_BLANK_UNBLANK.
461 * Return !0 for any modes that are unimplemented.
464 static int xxxfb_blank(int blank_mode, struct fb_info *info)
466 /* ... */
467 return 0;
470 /* ------------ Accelerated Functions --------------------- */
473 * We provide our own functions if we have hardware acceleration
474 * or non packed pixel format layouts. If we have no hardware
475 * acceleration, we can use a generic unaccelerated function. If using
476 * a pack pixel format just use the functions in cfb_*.c. Each file
477 * has one of the three different accel functions we support.
481 * xxxfb_fillrect - REQUIRED function. Can use generic routines if
482 * non acclerated hardware and packed pixel based.
483 * Draws a rectangle on the screen.
485 * @info: frame buffer structure that represents a single frame buffer
486 * @region: The structure representing the rectangular region we
487 * wish to draw to.
489 * This drawing operation places/removes a retangle on the screen
490 * depending on the rastering operation with the value of color which
491 * is in the current color depth format.
493 void xxxfb_fillrect(struct fb_info *p, const struct fb_fillrect *region)
495 /* Meaning of struct fb_fillrect
497 * @dx: The x and y corrdinates of the upper left hand corner of the
498 * @dy: area we want to draw to.
499 * @width: How wide the rectangle is we want to draw.
500 * @height: How tall the rectangle is we want to draw.
501 * @color: The color to fill in the rectangle with.
502 * @rop: The raster operation. We can draw the rectangle with a COPY
503 * of XOR which provides erasing effect.
508 * xxxfb_copyarea - REQUIRED function. Can use generic routines if
509 * non acclerated hardware and packed pixel based.
510 * Copies one area of the screen to another area.
512 * @info: frame buffer structure that represents a single frame buffer
513 * @area: Structure providing the data to copy the framebuffer contents
514 * from one region to another.
516 * This drawing operation copies a rectangular area from one area of the
517 * screen to another area.
519 void xxxfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
522 * @dx: The x and y coordinates of the upper left hand corner of the
523 * @dy: destination area on the screen.
524 * @width: How wide the rectangle is we want to copy.
525 * @height: How tall the rectangle is we want to copy.
526 * @sx: The x and y coordinates of the upper left hand corner of the
527 * @sy: source area on the screen.
533 * xxxfb_imageblit - REQUIRED function. Can use generic routines if
534 * non acclerated hardware and packed pixel based.
535 * Copies a image from system memory to the screen.
537 * @info: frame buffer structure that represents a single frame buffer
538 * @image: structure defining the image.
540 * This drawing operation draws a image on the screen. It can be a
541 * mono image (needed for font handling) or a color image (needed for
542 * tux).
544 void xxxfb_imageblit(struct fb_info *p, const struct fb_image *image)
547 * @dx: The x and y coordinates of the upper left hand corner of the
548 * @dy: destination area to place the image on the screen.
549 * @width: How wide the image is we want to copy.
550 * @height: How tall the image is we want to copy.
551 * @fg_color: For mono bitmap images this is color data for
552 * @bg_color: the foreground and background of the image to
553 * write directly to the frmaebuffer.
554 * @depth: How many bits represent a single pixel for this image.
555 * @data: The actual data used to construct the image on the display.
556 * @cmap: The colormap used for color images.
560 * The generic function, cfb_imageblit, expects that the bitmap scanlines are
561 * padded to the next byte. Most hardware accelerators may require padding to
562 * the next u16 or the next u32. If that is the case, the driver can specify
563 * this by setting info->pixmap.scan_align = 2 or 4. See a more
564 * comprehensive description of the pixmap below.
569 * xxxfb_cursor - OPTIONAL. If your hardware lacks support
570 * for a cursor, leave this field NULL.
572 * @info: frame buffer structure that represents a single frame buffer
573 * @cursor: structure defining the cursor to draw.
575 * This operation is used to set or alter the properities of the
576 * cursor.
578 * Returns negative errno on error, or zero on success.
580 int xxxfb_cursor(struct fb_info *info, struct fb_cursor *cursor)
583 * @set: Which fields we are altering in struct fb_cursor
584 * @enable: Disable or enable the cursor
585 * @rop: The bit operation we want to do.
586 * @mask: This is the cursor mask bitmap.
587 * @dest: A image of the area we are going to display the cursor.
588 * Used internally by the driver.
589 * @hot: The hot spot.
590 * @image: The actual data for the cursor image.
592 * NOTES ON FLAGS (cursor->set):
594 * FB_CUR_SETIMAGE - the cursor image has changed (cursor->image.data)
595 * FB_CUR_SETPOS - the cursor position has changed (cursor->image.dx|dy)
596 * FB_CUR_SETHOT - the cursor hot spot has changed (cursor->hot.dx|dy)
597 * FB_CUR_SETCMAP - the cursor colors has changed (cursor->fg_color|bg_color)
598 * FB_CUR_SETSHAPE - the cursor bitmask has changed (cursor->mask)
599 * FB_CUR_SETSIZE - the cursor size has changed (cursor->width|height)
600 * FB_CUR_SETALL - everything has changed
602 * NOTES ON ROPs (cursor->rop, Raster Operation)
604 * ROP_XOR - cursor->image.data XOR cursor->mask
605 * ROP_COPY - curosr->image.data AND cursor->mask
607 * OTHER NOTES:
609 * - fbcon only supports a 2-color cursor (cursor->image.depth = 1)
610 * - The fb_cursor structure, @cursor, _will_ always contain valid
611 * fields, whether any particular bitfields in cursor->set is set
612 * or not.
617 * xxxfb_rotate - NOT a required function. If your hardware
618 * supports rotation the whole screen then
619 * you would provide a hook for this.
621 * @info: frame buffer structure that represents a single frame buffer
622 * @angle: The angle we rotate the screen.
624 * This operation is used to set or alter the properities of the
625 * cursor.
627 void xxxfb_rotate(struct fb_info *info, int angle)
629 /* Will be deprecated */
633 * xxxfb_sync - NOT a required function. Normally the accel engine
634 * for a graphics card take a specific amount of time.
635 * Often we have to wait for the accelerator to finish
636 * its operation before we can write to the framebuffer
637 * so we can have consistent display output.
639 * @info: frame buffer structure that represents a single frame buffer
641 * If the driver has implemented its own hardware-based drawing function,
642 * implementing this function is highly recommended.
644 int xxxfb_sync(struct fb_info *info)
646 return 0;
650 * Frame buffer operations
653 static struct fb_ops xxxfb_ops = {
654 .owner = THIS_MODULE,
655 .fb_open = xxxfb_open,
656 .fb_read = xxxfb_read,
657 .fb_write = xxxfb_write,
658 .fb_release = xxxfb_release,
659 .fb_check_var = xxxfb_check_var,
660 .fb_set_par = xxxfb_set_par,
661 .fb_setcolreg = xxxfb_setcolreg,
662 .fb_blank = xxxfb_blank,
663 .fb_pan_display = xxxfb_pan_display,
664 .fb_fillrect = xxxfb_fillrect, /* Needed !!! */
665 .fb_copyarea = xxxfb_copyarea, /* Needed !!! */
666 .fb_imageblit = xxxfb_imageblit, /* Needed !!! */
667 .fb_cursor = xxxfb_cursor, /* Optional !!! */
668 .fb_rotate = xxxfb_rotate,
669 .fb_sync = xxxfb_sync,
670 .fb_ioctl = xxxfb_ioctl,
671 .fb_mmap = xxxfb_mmap,
674 /* ------------------------------------------------------------------------- */
677 * Initialization
680 /* static int __init xxfb_probe (struct platform_device *pdev) -- for platform devs */
681 static int xxxfb_probe(struct pci_dev *dev, const struct pci_device_id *ent)
683 struct fb_info *info;
684 struct xxx_par *par;
685 struct device *device = &dev->dev; /* or &pdev->dev */
686 int cmap_len, retval;
689 * Dynamically allocate info and par
691 info = framebuffer_alloc(sizeof(struct xxx_par), device);
693 if (!info) {
694 /* goto error path */
697 par = info->par;
700 * Here we set the screen_base to the virtual memory address
701 * for the framebuffer. Usually we obtain the resource address
702 * from the bus layer and then translate it to virtual memory
703 * space via ioremap. Consult ioport.h.
705 info->screen_base = framebuffer_virtual_memory;
706 info->fbops = &xxxfb_ops;
707 info->fix = xxxfb_fix;
708 info->pseudo_palette = pseudo_palette; /* The pseudopalette is an
709 * 16-member array
712 * Set up flags to indicate what sort of acceleration your
713 * driver can provide (pan/wrap/copyarea/etc.) and whether it
714 * is a module -- see FBINFO_* in include/linux/fb.h
716 * If your hardware can support any of the hardware accelerated functions
717 * fbcon performance will improve if info->flags is set properly.
719 * FBINFO_HWACCEL_COPYAREA - hardware moves
720 * FBINFO_HWACCEL_FILLRECT - hardware fills
721 * FBINFO_HWACCEL_IMAGEBLIT - hardware mono->color expansion
722 * FBINFO_HWACCEL_YPAN - hardware can pan display in y-axis
723 * FBINFO_HWACCEL_YWRAP - hardware can wrap display in y-axis
724 * FBINFO_HWACCEL_DISABLED - supports hardware accels, but disabled
725 * FBINFO_READS_FAST - if set, prefer moves over mono->color expansion
726 * FBINFO_MISC_TILEBLITTING - hardware can do tile blits
728 * NOTE: These are for fbcon use only.
730 info->flags = FBINFO_DEFAULT;
732 /********************* This stage is optional ******************************/
734 * The struct pixmap is a scratch pad for the drawing functions. This
735 * is where the monochrome bitmap is constructed by the higher layers
736 * and then passed to the accelerator. For drivers that uses
737 * cfb_imageblit, you can skip this part. For those that have a more
738 * rigorous requirement, this stage is needed
741 /* PIXMAP_SIZE should be small enough to optimize drawing, but not
742 * large enough that memory is wasted. A safe size is
743 * (max_xres * max_font_height/8). max_xres is driver dependent,
744 * max_font_height is 32.
746 info->pixmap.addr = kmalloc(PIXMAP_SIZE, GFP_KERNEL);
747 if (!info->pixmap.addr) {
748 /* goto error */
751 info->pixmap.size = PIXMAP_SIZE;
754 * FB_PIXMAP_SYSTEM - memory is in system ram
755 * FB_PIXMAP_IO - memory is iomapped
756 * FB_PIXMAP_SYNC - if set, will call fb_sync() per access to pixmap,
757 * usually if FB_PIXMAP_IO is set.
759 * Currently, FB_PIXMAP_IO is unimplemented.
761 info->pixmap.flags = FB_PIXMAP_SYSTEM;
764 * scan_align is the number of padding for each scanline. It is in bytes.
765 * Thus for accelerators that need padding to the next u32, put 4 here.
767 info->pixmap.scan_align = 4;
770 * buf_align is the amount to be padded for the buffer. For example,
771 * the i810fb needs a scan_align of 2 but expects it to be fed with
772 * dwords, so a buf_align = 4 is required.
774 info->pixmap.buf_align = 4;
776 /* access_align is how many bits can be accessed from the framebuffer
777 * ie. some epson cards allow 16-bit access only. Most drivers will
778 * be safe with u32 here.
780 * NOTE: This field is currently unused.
782 info->pixmap.access_align = 32;
783 /***************************** End optional stage ***************************/
786 * This should give a reasonable default video mode. The following is
787 * done when we can set a video mode.
789 if (!mode_option)
790 mode_option = "640x480@60";
792 retval = fb_find_mode(&info->var, info, mode_option, NULL, 0, NULL, 8);
794 if (!retval || retval == 4)
795 return -EINVAL;
797 /* This has to be done! */
798 if (fb_alloc_cmap(&info->cmap, cmap_len, 0))
799 return -ENOMEM;
802 * The following is done in the case of having hardware with a static
803 * mode. If we are setting the mode ourselves we don't call this.
805 info->var = xxxfb_var;
808 * For drivers that can...
810 xxxfb_check_var(&info->var, info);
813 * Does a call to fb_set_par() before register_framebuffer needed? This
814 * will depend on you and the hardware. If you are sure that your driver
815 * is the only device in the system, a call to fb_set_par() is safe.
817 * Hardware in x86 systems has a VGA core. Calling set_par() at this
818 * point will corrupt the VGA console, so it might be safer to skip a
819 * call to set_par here and just allow fbcon to do it for you.
821 /* xxxfb_set_par(info); */
823 if (register_framebuffer(info) < 0) {
824 fb_dealloc_cmap(&info->cmap);
825 return -EINVAL;
827 printk(KERN_INFO "fb%d: %s frame buffer device\n", info->node,
828 info->fix.id);
829 pci_set_drvdata(dev, info); /* or platform_set_drvdata(pdev, info) */
830 return 0;
834 * Cleanup
836 /* static void xxxfb_remove(struct platform_device *pdev) */
837 static void xxxfb_remove(struct pci_dev *dev)
839 struct fb_info *info = pci_get_drvdata(dev);
840 /* or platform_get_drvdata(pdev); */
842 if (info) {
843 unregister_framebuffer(info);
844 fb_dealloc_cmap(&info->cmap);
845 /* ... */
846 framebuffer_release(info);
850 #ifdef CONFIG_PCI
851 #ifdef CONFIG_PM
853 * xxxfb_suspend - Optional but recommended function. Suspend the device.
854 * @dev: PCI device
855 * @msg: the suspend event code.
857 * See Documentation/power/devices.txt for more information
859 static int xxxfb_suspend(struct pci_dev *dev, pm_message_t msg)
861 struct fb_info *info = pci_get_drvdata(dev);
862 struct xxxfb_par *par = info->par;
864 /* suspend here */
865 return 0;
869 * xxxfb_resume - Optional but recommended function. Resume the device.
870 * @dev: PCI device
872 * See Documentation/power/devices.txt for more information
874 static int xxxfb_resume(struct pci_dev *dev)
876 struct fb_info *info = pci_get_drvdata(dev);
877 struct xxxfb_par *par = info->par;
879 /* resume here */
880 return 0;
882 #else
883 #define xxxfb_suspend NULL
884 #define xxxfb_resume NULL
885 #endif /* CONFIG_PM */
887 static struct pci_device_id xxxfb_id_table[] = {
888 { PCI_VENDOR_ID_XXX, PCI_DEVICE_ID_XXX,
889 PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY << 16,
890 PCI_CLASS_MASK, 0 },
891 { 0, }
894 /* For PCI drivers */
895 static struct pci_driver xxxfb_driver = {
896 .name = "xxxfb",
897 .id_table = xxxfb_id_table,
898 .probe = xxxfb_probe,
899 .remove = xxxfb_remove,
900 .suspend = xxxfb_suspend, /* optional but recommended */
901 .resume = xxxfb_resume, /* optional but recommended */
904 MODULE_DEVICE_TABLE(pci, xxxfb_id_table);
906 int __init xxxfb_init(void)
909 * For kernel boot options (in 'video=xxxfb:<options>' format)
911 #ifndef MODULE
912 char *option = NULL;
914 if (fb_get_options("xxxfb", &option))
915 return -ENODEV;
916 xxxfb_setup(option);
917 #endif
919 return pci_register_driver(&xxxfb_driver);
922 static void __exit xxxfb_exit(void)
924 pci_unregister_driver(&xxxfb_driver);
926 #else /* non PCI, platform drivers */
927 #include <linux/platform_device.h>
928 /* for platform devices */
930 #ifdef CONFIG_PM
932 * xxxfb_suspend - Optional but recommended function. Suspend the device.
933 * @dev: platform device
934 * @msg: the suspend event code.
936 * See Documentation/power/devices.txt for more information
938 static int xxxfb_suspend(struct platform_device *dev, pm_message_t msg)
940 struct fb_info *info = platform_get_drvdata(dev);
941 struct xxxfb_par *par = info->par;
943 /* suspend here */
944 return 0;
948 * xxxfb_resume - Optional but recommended function. Resume the device.
949 * @dev: platform device
951 * See Documentation/power/devices.txt for more information
953 static int xxxfb_resume(struct platform_dev *dev)
955 struct fb_info *info = platform_get_drvdata(dev);
956 struct xxxfb_par *par = info->par;
958 /* resume here */
959 return 0;
961 #else
962 #define xxxfb_suspend NULL
963 #define xxxfb_resume NULL
964 #endif /* CONFIG_PM */
966 static struct platform_device_driver xxxfb_driver = {
967 .probe = xxxfb_probe,
968 .remove = xxxfb_remove,
969 .suspend = xxxfb_suspend, /* optional but recommended */
970 .resume = xxxfb_resume, /* optional but recommended */
971 .driver = {
972 .name = "xxxfb",
976 static struct platform_device *xxxfb_device;
978 #ifndef MODULE
980 * Setup
984 * Only necessary if your driver takes special options,
985 * otherwise we fall back on the generic fb_setup().
987 int __init xxxfb_setup(char *options)
989 /* Parse user specified options (`video=xxxfb:') */
991 #endif /* MODULE */
993 static int __init xxxfb_init(void)
995 int ret;
997 * For kernel boot options (in 'video=xxxfb:<options>' format)
999 #ifndef MODULE
1000 char *option = NULL;
1002 if (fb_get_options("xxxfb", &option))
1003 return -ENODEV;
1004 xxxfb_setup(option);
1005 #endif
1006 ret = platform_driver_register(&xxxfb_driver);
1008 if (!ret) {
1009 xxxfb_device = platform_device_register_simple("xxxfb", 0,
1010 NULL, 0);
1012 if (IS_ERR(xxxfb_device)) {
1013 platform_driver_unregister(&xxxfb_driver);
1014 ret = PTR_ERR(xxxfb_device);
1018 return ret;
1021 static void __exit xxxfb_exit(void)
1023 platform_device_unregister(xxxfb_device);
1024 platform_driver_unregister(&xxxfb_driver);
1026 #endif /* CONFIG_PCI */
1028 /* ------------------------------------------------------------------------- */
1032 * Modularization
1035 module_init(xxxfb_init);
1036 module_exit(xxxfb_exit);
1038 MODULE_LICENSE("GPL");