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skeletonfb.c
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linux-6.19.14/drivers/video/fbdev/skeletonfb.c
1/* 2 * linux/drivers/video/skeletonfb.c -- Skeleton for a frame buffer device 3 * 4 * Modified to new api Jan 2001 by James Simmons (jsimmons@transvirtual.com) 5 * 6 * Created 28 Dec 1997 by Geert Uytterhoeven 7 * 8 * 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. 15 * 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. 30 * 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. 39 * 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. 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 data 66 */ 67static char *mode_option; 68 69/* 70 * If your driver supports multiple boards, you should make the 71 * below data types arrays, or allocate them dynamically (using kmalloc()). 72 */ 73 74/* 75 * This structure defines the hardware state of the graphics card. Normally 76 * you place this in a header file in linux/include/video. This file usually 77 * also includes register information. That allows other driver subsystems 78 * and userland applications the ability to use the same header file to 79 * 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_screeninfo 85 * if we don't use modedb. If we do use modedb see xxxfb_init how to use it 86 * 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 some 100 * also support multiple monitors where each display can have 101 * its own unique data. In this case each display could be 102 * represented by a separate framebuffer device thus a separate 103 * struct fb_info. Now the struct xxx_par represents the graphics 104 * hardware state thus only one exist per card. In this case the 105 * struct xxx_par for each graphics card would be shared between 106 * 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 be 109 * aware of the entire hardware state that affects it because they share 110 * the same xxx_par struct. The other side of the coin is multiple 111 * graphics cards that pass data around until it is finally displayed 112 * on one monitor. Such examples are the voodoo 1 cards and high end 113 * NUMA graphics servers. For this case we have a bunch of pars, each 114 * one that represents a graphics state, that belong to one struct 115 * fb_info. Their you would want to have *par point to a array of device 116 * states and have each struct fb_ops function deal with all those 117 * states. I hope this covers every possible hardware design. If not 118 * feel free to send your ideas at jsimmons@users.sf.net 119 */ 120 121 /* 122 * If your driver supports multiple boards or it supports multiple 123 * framebuffers, you should make these arrays, or allocate them 124 * dynamically using framebuffer_alloc() and free them with 125 * framebuffer_release(). 126 */ 127static struct fb_info info; 128 129 /* 130 * Each one represents the state of the hardware. Most hardware have 131 * 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 is 137 * first accessed. 138 * @info: frame buffer structure that represents a single frame buffer 139 * @user: tell us if the userland (value=1) or the console is accessing 140 * 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 it 144 * is used is to change from a text mode hardware state to a graphics 145 * 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 framebuffer 156 * device is closed. 157 * @info: frame buffer structure that represents a single frame buffer 158 * @user: tell us if the userland (value=1) or the console is accessing 159 * the framebuffer. 160 * 161 * Thus function is called when we close /dev/fb or the framebuffer 162 * 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 state 164 * 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 structure 176 * @info: frame buffer structure that represents a single frame buffer 177 * 178 * Checks to see if the hardware supports the state requested by 179 * 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 do 181 * 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 we 183 * intent to only test a mode and not actually set it. The stuff in 184 * modedb.c is a example of this. If the var passed in is slightly 185 * off by what the hardware can support then we alter the var PASSED in 186 * to what we can do. 187 * 188 * For values that are off, this function must round them _up_ to the 189 * next value that is supported by the hardware. If the value is 190 * greater than the highest value supported by the hardware, then this 191 * 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. In 195 * this case, it is more acceptable that this function just return 196 * a copy of the currently working var (info->var). Better is to not 197 * implement this function, as the upper layer will do the copying 198 * of the current var for you. 199 * 200 * Note: This is the only function where the contents of var can be 201 * freely adjusted after the driver has been registered. If you find 202 * that you have code outside of this function that alters the content 203 * of var, then you are doing something wrong. Note also that the 204 * contents of info->var must be left untouched at all times after 205 * 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 buffer 218 * 219 * Using the fb_var_screeninfo in fb_info we set the resolution of the 220 * this particular framebuffer. This function alters the par AND the 221 * fb_fix_screeninfo stored in fb_info. It doesn't not alter var in 222 * fb_info since we are using that data. This means we depend on the 223 * 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 a 226 * known working state. 227 * 228 * xxxfb_check_var is always called before xxxfb_set_par to ensure that 229 * 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 to 235 * a known working state, especially if it came back from another 236 * 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 here 250 * } 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 programming 264 * @red: The red value which can be up to 16 bits wide 265 * @green: The green value which can be up to 16 bits wide 266 * @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 structure 269 * 270 * Set a single color register. The values supplied have a 16 bit 271 * magnitude which needs to be scaled in this function for the hardware. 272 * Things to take into consideration are how many color registers, if 273 * any, are supported with the current color visual. With truecolor mode 274 * no color palettes are supported. Here a pseudo palette is created 275 * which we store the value in pseudo_palette in struct fb_info. For 276 * pseudocolor mode we have a limited color palette. To deal with this 277 * we can program what color is displayed for a particular pixel value. 278 * DirectColor is similar in that we can program each color field. If 279 * 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 transp 291 */ 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 bitfield 301 * var->{color}.length contains length of bitfield 302 * {hardwarespecific} contains width of DAC 303 * 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 than 311 * bits_per_pixel bits and is stored in the upper 312 * bits of the pixel value 313 * var->{color}.length is set so that 1 << length is the number of 314 * available palette entries 315 * pseudo_palette is not used 316 * RAMDAC[X] is programmed to (red, green, blue) 317 * color depth = var->{color}.length 318 * 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 0 325 * white = (1 << var->{color}.length) - 1, black = 0 326 * pseudo_palette is not used 327 * RAMDAC does not exist 328 * color depth is always 2 329 * 330 * Truecolor: 331 * does not use RAMDAC (usually has 3 of them). 332 * var->{color}.offset contains start of bitfield 333 * var->{color}.length contains length of bitfield 334 * pseudo_palette is programmed to (red << red.offset) | 335 * (green << green.offset) | 336 * (blue << blue.offset) | 337 * (transp << transp.offset) 338 * RAMDAC does not exist 339 * color depth = SUM(var->{color}.length}) 340 * 341 * The color depth is used by fbcon for choosing the logo and also 342 * for color palette transformation if color depth < 4 343 * 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 needs 349 * to look at the fix->visual. 350 * 351 * Another common mistake is using bits_per_pixel to calculate the color 352 * depth. The bits_per_pixel field does not directly translate to color 353 * depth. You have to compute for the color depth (using the color 354 * bitfields) and fix->visual as seen above. 355 */ 356 357 /* 358 * This is the point where the color is converted to something that 359 * 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_TOHW 367 /* 368 * This is the point where the function feeds the color to the hardware 369 * palette after converting the colors to something acceptable by 370 * the hardware. Note, only FB_VISUAL_DIRECTCOLOR and 371 * 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 not 373 * 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 of 380 * info->pseudo_palette. This structure is used _only_ by fbcon, thus 381 * it only contains 16 entries to match the number of colors supported 382 * by the console. The pseudo_palette is used only if the visual is 383 * in directcolor or truecolor mode. With other visuals, the 384 * 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, each 387 * entry can be written directly to the framebuffer without any conversion. 388 * The pseudo_palette is (void *). However, if using the generic 389 * drawing functions (cfb_imageblit, cfb_fillrect), the pseudo_palette 390 * must be casted to (u32 *) _regardless_ of the bits per pixel. If the 391 * driver is using its own drawing functions, then it can use whatever 392 * 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 structure 416 * @info: frame buffer structure that represents a single frame buffer 417 * 418 * Pan (or wrap, depending on the `vmode' field) the display using the 419 * `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 this 429 * 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 of 434 * 0 in both xpanstep and ypanstep means that this function will never 435 * 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 buffer 446 * 447 * Blank the screen if blank_mode != FB_BLANK_UNBLANK, else unblank. 448 * Return 0 if blanking succeeded, != 0 if un-/blanking failed due to 449 * e.g. a video mode which doesn't support it. 450 * 451 * Implements VESA suspend and powerdown modes on hardware that supports 452 * disabling hsync/vsync: 453 * 454 * FB_BLANK_NORMAL = display is blanked, syncs are on. 455 * FB_BLANK_HSYNC_SUSPEND = hsync off 456 * FB_BLANK_VSYNC_SUSPEND = vsync off 457 * FB_BLANK_POWERDOWN = hsync and vsync off 458 * 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 acceleration 473 * or non packed pixel format layouts. If we have no hardware 474 * acceleration, we can use a generic unaccelerated function. If using 475 * a pack pixel format just use the functions in cfb_*.c. Each file 476 * has one of the three different accel functions we support. 477 */ 478 479/** 480 * xxxfb_fillrect - REQUIRED function. Can use generic routines if 481 * 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 buffer 485 * @region: The structure representing the rectangular region we 486 * wish to draw to. 487 * 488 * This drawing operation places/removes a retangle on the screen 489 * depending on the rastering operation with the value of color which 490 * 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_fillrect 495 * 496 * @dx: The x and y corrdinates of the upper left hand corner of the 497 * @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 COPY 502 * of XOR which provides erasing effect. 503 */ 504} 505 506/** 507 * xxxfb_copyarea - REQUIRED function. Can use generic routines if 508 * 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 buffer 512 * @area: Structure providing the data to copy the framebuffer contents 513 * from one region to another. 514 * 515 * This drawing operation copies a rectangular area from one area of the 516 * 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 the 522 * @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 the 526 * @sy: source area on the screen. 527 */ 528} 529 530 531/** 532 * xxxfb_imageblit - REQUIRED function. Can use generic routines if 533 * 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 buffer 537 * @image: structure defining the image. 538 * 539 * This drawing operation draws a image on the screen. It can be a 540 * mono image (needed for font handling) or a color image (needed for 541 * 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 the 547 * @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 for 551 * @bg_color: the foreground and background of the image to 552 * 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 are 560 * padded to the next byte. Most hardware accelerators may require padding to 561 * the next u16 or the next u32. If that is the case, the driver can specify 562 * this by setting info->pixmap.scan_align = 2 or 4. See a more 563 * comprehensive description of the pixmap below. 564 */ 565} 566 567/** 568 * xxxfb_cursor - OPTIONAL. If your hardware lacks support 569 * for a cursor, leave this field NULL. 570 * 571 * @info: frame buffer structure that represents a single frame buffer 572 * @cursor: structure defining the cursor to draw. 573 * 574 * This operation is used to set or alter the properities of the 575 * 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_cursor 583 * @enable: Disable or enable the cursor 584 * @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 changed 600 * 601 * NOTES ON ROPs (cursor->rop, Raster Operation) 602 * 603 * ROP_XOR - cursor->image.data XOR cursor->mask 604 * ROP_COPY - curosr->image.data AND cursor->mask 605 * 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 valid 610 * fields, whether any particular bitfields in cursor->set is set 611 * or not. 612 */ 613} 614 615/** 616 * xxxfb_sync - NOT a required function. Normally the accel engine 617 * for a graphics card take a specific amount of time. 618 * Often we have to wait for the accelerator to finish 619 * its operation before we can write to the framebuffer 620 * so we can have consistent display output. 621 * 622 * @info: frame buffer structure that represents a single frame buffer 623 * 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 operations 634 */ 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 * Initialization 660 */ 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 par 679 */ 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 address 690 * for the framebuffer. Usually we obtain the resource address 691 * from the bus layer and then translate it to virtual memory 692 * 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 an 698 * 16-member array 699 */ 700 /* 701 * Set up flags to indicate what sort of acceleration your 702 * driver can provide (pan/wrap/copyarea/etc.) and whether it 703 * is a module -- see FBINFO_* in include/linux/fb.h 704 * 705 * If your hardware can support any of the hardware accelerated functions 706 * fbcon performance will improve if info->flags is set properly. 707 * 708 * FBINFO_HWACCEL_COPYAREA - hardware moves 709 * FBINFO_HWACCEL_FILLRECT - hardware fills 710 * FBINFO_HWACCEL_IMAGEBLIT - hardware mono->color expansion 711 * FBINFO_HWACCEL_YPAN - hardware can pan display in y-axis 712 * FBINFO_HWACCEL_YWRAP - hardware can wrap display in y-axis 713 * FBINFO_HWACCEL_DISABLED - supports hardware accels, but disabled 714 * FBINFO_READS_FAST - if set, prefer moves over mono->color expansion 715 * FBINFO_MISC_TILEBLITTING - hardware can do tile blits 716 * 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. This 724 * is where the monochrome bitmap is constructed by the higher layers 725 * and then passed to the accelerator. For drivers that uses 726 * cfb_imageblit, you can skip this part. For those that have a more 727 * rigorous requirement, this stage is needed 728 */ 729 730 /* PIXMAP_SIZE should be small enough to optimize drawing, but not 731 * large enough that memory is wasted. A safe size is 732 * (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 ram 744 * FB_PIXMAP_IO - memory is iomapped 745 * 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 with 761 * 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 framebuffer 766 * ie. some epson cards allow 16-bit access only. Most drivers will 767 * 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 is 776 * 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 static 792 * 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? This 803 * will depend on you and the hardware. If you are sure that your driver 804 * 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 this 807 * point will corrupt the VGA console, so it might be safer to skip a 808 * 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 * Cleanup 823 */ 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_PCI 839#ifdef CONFIG_PM 840/** 841 * xxxfb_suspend - Optional but recommended function. Suspend the device. 842 * @dev: PCI device 843 * @msg: the suspend event code. 844 * 845 * See Documentation/driver-api/pm/devices.rst for more information 846 */ 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 device 859 * 860 * See Documentation/driver-api/pm/devices.rst for more information 861 */ 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#else 871#define xxxfb_suspend NULL 872#define xxxfb_resume NULL 873#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 MODULE 901 char *option = NULL; 902 903 if (fb_get_options("xxxfb", &option)) 904 return -ENODEV; 905 xxxfb_setup(option); 906#endif 907 908 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_PM 920/** 921 * xxxfb_suspend - Optional but recommended function. Suspend the device. 922 * @dev: platform device 923 * @msg: the suspend event code. 924 * 925 * See Documentation/driver-api/pm/devices.rst for more information 926 */ 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 device 939 * 940 * See Documentation/driver-api/pm/devices.rst for more information 941 */ 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#else 951#define xxxfb_suspend NULL 952#define xxxfb_resume NULL 953#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 MODULE 968 /* 969 * Setup 970 */ 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 MODULE 989 char *option = NULL; 990#endif 991 992 if (fb_modesetting_disabled("xxxfb")) 993 return -ENODEV; 994 995#ifndef MODULE 996 if (fb_get_options("xxxfb", &option)) 997 return -ENODEV; 998 xxxfb_setup(option); 999#endif 1000 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 * Modularization 1027 */ 1028 1029module_init(xxxfb_init); 1030module_exit(xxxfb_exit); 1031 1032MODULE_LICENSE("GPL");
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