drivers/block/floppy.c

/* */
This source file includes following definitions.
select_callback
floppy_select
motor_on_callback
motor_off_callback
floppy_on
floppy_off
request_done
floppy_change
setup_DMA
output_byte
result
bad_flp_intr
perpendicular_mode
configure_fdc_mode
tell_sector
rw_interrupt
setup_rw_floppy
seek_interrupt
transfer
recal_interrupt
unexpected_floppy_interrupt
recalibrate_floppy
reset_interrupt
reset_floppy
floppy_shutdown
shake_done
retry_recal
shake_zero
shake_one
floppy_ready
setup_format_params
redo_fd_request
do_fd_request
fd_ioctl
find_base
config_types
floppy_open
floppy_release
ignore_interrupt
floppy_interrupt
floppy_init
   1 /*
   2  *  linux/kernel/floppy.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  */
   6 
   7 /*
   8  * 02.12.91 - Changed to static variables to indicate need for reset
   9  * and recalibrate. This makes some things easier (output_byte reset
  10  * checking etc), and means less interrupt jumping in case of errors,
  11  * so the code is hopefully easier to understand.
  12  */
  13 
  14 /*
  15  * This file is certainly a mess. I've tried my best to get it working,
  16  * but I don't like programming floppies, and I have only one anyway.
  17  * Urgel. I should check for more errors, and do more graceful error
  18  * recovery. Seems there are problems with several drives. I've tried to
  19  * correct them. No promises. 
  20  */
  21 
  22 /*
  23  * As with hd.c, all routines within this file can (and will) be called
  24  * by interrupts, so extreme caution is needed. A hardware interrupt
  25  * handler may not sleep, or a kernel panic will happen. Thus I cannot
  26  * call "floppy-on" directly, but have to set a special timer interrupt
  27  * etc.
  28  */
  29 
  30 /*
  31  * 28.02.92 - made track-buffering routines, based on the routines written
  32  * by entropy@wintermute.wpi.edu (Lawrence Foard). Linus.
  33  */
  34 
  35 /*
  36  * Automatic floppy-detection and formatting written by Werner Almesberger
  37  * (almesber@nessie.cs.id.ethz.ch), who also corrected some problems with
  38  * the floppy-change signal detection.
  39  */
  40 
  41 /*
  42  * 1992/7/22 -- Hennus Bergman: Added better error reporting, fixed 
  43  * FDC data overrun bug, added some preliminary stuff for vertical
  44  * recording support.
  45  *
  46  * 1992/9/17: Added DMA allocation & DMA functions. -- hhb.
  47  *
  48  * TODO: Errors are still not counted properly.
  49  */
  50 
  51 /* 1992/9/20
  52  * Modifications for ``Sector Shifting'' by Rob Hooft (hooft@chem.ruu.nl)
  53  * modelled after the freeware MS/DOS program fdformat/88 V1.8 by 
  54  * Christoph H. Hochst\"atter.
  55  * I have fixed the shift values to the ones I always use. Maybe a new
  56  * ioctl() should be created to be able to modify them.
  57  * There is a bug in the driver that makes it impossible to format a
  58  * floppy as the first thing after bootup.
  59  */
  60 
  61 /*
  62  * 1993/4/29 -- Linus -- cleaned up the timer handling in the kernel, and
  63  * this helped the floppy driver as well. Much cleaner, and still seems to
  64  * work.
  65  */
  66 
  67 #define REALLY_SLOW_IO
  68 #define FLOPPY_IRQ 6
  69 #define FLOPPY_DMA 2
  70 
  71 #include <linux/sched.h>
  72 #include <linux/fs.h>
  73 #include <linux/kernel.h>
  74 #include <linux/timer.h>
  75 #include <linux/fdreg.h>
  76 #include <linux/fd.h>
  77 #include <linux/errno.h>
  78 
  79 #include <asm/dma.h>
  80 #include <asm/system.h>
  81 #include <asm/io.h>
  82 #include <asm/segment.h>
  83 
  84 #define MAJOR_NR FLOPPY_MAJOR
  85 #include "blk.h"
  86 
  87 static unsigned int changed_floppies = 0, fake_change = 0;
  88 
  89 static int initial_reset_flag = 0;
  90 static int need_configure = 1;          /* for 82077 */
  91 static int recalibrate = 0;
  92 static int reset = 0;
  93 static int recover = 0; /* recalibrate immediately after resetting */
  94 static int seek = 0;
  95 
  96 static unsigned char current_DOR = 0x0C;
  97 static unsigned char running = 0;
  98 
  99 #define TYPE(x) ((x)>>2)
 100 #define DRIVE(x) ((x)&0x03)
 101 
 102 /*
 103  * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
 104  * max X times - some types of errors increase the errorcount by 2 or
 105  * even 3, so we might actually retry only X/2 times before giving up.
 106  */
 107 #define MAX_ERRORS 12
 108 
 109 /*
 110  * Maximum disk size (in kilobytes). This default is used whenever the
 111  * current disk size is unknown.
 112  */
 113 #define MAX_DISK_SIZE 1440
 114 
 115 /*
 116  * Maximum number of sectors in a track buffer. Track buffering is disabled
 117  * if tracks are bigger.
 118  */
 119 #define MAX_BUFFER_SECTORS 18
 120 
 121 /*
 122  * The DMA channel used by the floppy controller cannot access data at
 123  * addresses >= 16MB
 124  *
 125  * Went back to the 1MB limit, as some people had problems with the floppy
 126  * driver otherwise. It doesn't matter much for performance anyway, as most
 127  * floppy accesses go through the track buffer.
 128  */
 129 #define LAST_DMA_ADDR   (0x100000 - BLOCK_SIZE)
 130 
 131 /*
 132  * globals used by 'result()'
 133  */
 134 #define MAX_REPLIES 7
 135 static unsigned char reply_buffer[MAX_REPLIES];
 136 #define ST0 (reply_buffer[0])
 137 #define ST1 (reply_buffer[1])
 138 #define ST2 (reply_buffer[2])
 139 #define ST3 (reply_buffer[3])
 140 
 141 /*
 142  * This struct defines the different floppy types.
 143  *
 144  * The 'stretch' tells if the tracks need to be doubled for some
 145  * types (ie 360kB diskette in 1.2MB drive etc). Others should
 146  * be self-explanatory.
 147  */
 148 static struct floppy_struct floppy_type[] = {
 149         {    0, 0,0, 0,0,0x00,0x00,0x00,0x00,NULL },    /* no testing */
 150         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,NULL },    /* 360kB PC diskettes */
 151         { 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,NULL },    /* 1.2 MB AT-diskettes */
 152         {  720, 9,2,40,1,0x2A,0x02,0xDF,0x50,NULL },    /* 360kB in 720kB drive */
 153         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,NULL },    /* 3.5" 720kB diskette */
 154         {  720, 9,2,40,1,0x23,0x01,0xDF,0x50,NULL },    /* 360kB in 1.2MB drive */
 155         { 1440, 9,2,80,0,0x23,0x01,0xDF,0x50,NULL },    /* 720kB in 1.2MB drive */
 156         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL },    /* 1.44MB diskette */
 157 };
 158 
 159 /*
 160  * Auto-detection. Each drive type has a pair of formats which are
 161  * used in succession to try to read the disk. If the FDC cannot lock onto
 162  * the disk, the next format is tried. This uses the variable 'probing'.
 163  */
 164 static struct floppy_struct floppy_types[] = {
 165         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"360k/PC" }, /* 360kB PC diskettes */
 166         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"360k/PC" }, /* 360kB PC diskettes */
 167         { 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,"1.2M" },    /* 1.2 MB AT-diskettes */
 168         {  720, 9,2,40,1,0x23,0x01,0xDF,0x50,"360k/AT" }, /* 360kB in 1.2MB drive */
 169         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k" },    /* 3.5" 720kB diskette */
 170         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k" },    /* 3.5" 720kB diskette */
 171         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,"1.44M" },   /* 1.44MB diskette */
 172         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k/AT" }, /* 3.5" 720kB diskette */
 173 };
 174 
 175 /* Auto-detection: Disk type used until the next media change occurs. */
 176 struct floppy_struct *current_type[4] = { NULL, NULL, NULL, NULL };
 177 
 178 /* This type is tried first. */
 179 struct floppy_struct *base_type[4];
 180 
 181 /*
 182  * User-provided type information. current_type points to
 183  * the respective entry of this array.
 184  */
 185 struct floppy_struct user_params[4];
 186 
 187 static int floppy_sizes[] ={
 188         MAX_DISK_SIZE, MAX_DISK_SIZE, MAX_DISK_SIZE, MAX_DISK_SIZE,
 189          360, 360 ,360, 360,
 190         1200,1200,1200,1200,
 191          360, 360, 360, 360,
 192          720, 720, 720, 720,
 193          360, 360, 360, 360,
 194          720, 720, 720, 720,
 195         1440,1440,1440,1440
 196 };
 197 
 198 /*
 199  * The driver is trying to determine the correct media format
 200  * while probing is set. rw_interrupt() clears it after a
 201  * successful access.
 202  */
 203 static int probing = 0;
 204 
 205 /*
 206  * (User-provided) media information is _not_ discarded after a media change
 207  * if the corresponding keep_data flag is non-zero. Positive values are
 208  * decremented after each probe.
 209  */
 210 static int keep_data[4] = { 0,0,0,0 };
 211 
 212 /*
 213  * Announce successful media type detection and media information loss after
 214  * disk changes.
 215  * Also used to enable/disable printing of overrun warnings.
 216  */
 217 static ftd_msg[4] = { 0,0,0,0 };
 218 
 219 /* Prevent "aliased" accesses. */
 220 
 221 static fd_ref[4] = { 0,0,0,0 };
 222 static fd_device[4] = { 0,0,0,0 };
 223 
 224 /* Synchronization of FDC access. */
 225 static volatile int format_status = FORMAT_NONE, fdc_busy = 0;
 226 static struct wait_queue *fdc_wait = NULL, *format_done = NULL;
 227 
 228 /* Errors during formatting are counted here. */
 229 static int format_errors;
 230 
 231 /* Format request descriptor. */
 232 static struct format_descr format_req;
 233 
 234 /*
 235  * Current device number. Taken either from the block header or from the
 236  * format request descriptor.
 237  */
 238 #define CURRENT_DEVICE (format_status == FORMAT_BUSY ? format_req.device : \
 239    (CURRENT->dev))
 240 
 241 /* Current error count. */
 242 #define CURRENT_ERRORS (format_status == FORMAT_BUSY ? format_errors : \
 243     (CURRENT->errors))
 244 
 245 /*
 246  * Threshold for reporting FDC errors to the console.
 247  * Setting this to zero may flood your screen when using
 248  * ultra cheap floppies ;-)
 249  */
 250 static unsigned short min_report_error_cnt[4] = {2, 2, 2, 2};
 251 
 252 /*
 253  * Rate is 0 for 500kb/s, 1 for 300kbps, 2 for 250kbps
 254  * Spec1 is 0xSH, where S is stepping rate (F=1ms, E=2ms, D=3ms etc),
 255  * H is head unload time (1=16ms, 2=32ms, etc)
 256  *
 257  * Spec2 is (HLD<<1 | ND), where HLD is head load time (1=2ms, 2=4 ms etc)
 258  * and ND is set means no DMA. Hardcoded to 6 (HLD=6ms, use DMA).
 259  */
 260 
 261 /*
 262  * Track buffer and block buffer (in case track buffering doesn't work).
 263  * Because these are written to by the DMA controller, they must
 264  * not contain a 64k byte boundary crossing, or data will be
 265  * corrupted/lost. Alignment of these is enforced in boot/head.s.
 266  * Note that you must not change the sizes below without updating head.s.
 267  */
 268 extern char tmp_floppy_area[BLOCK_SIZE];
 269 extern char floppy_track_buffer[512*2*MAX_BUFFER_SECTORS];
 270 
 271 static void redo_fd_request(void);
 272 
 273 /*
 274  * These are global variables, as that's the easiest way to give
 275  * information to interrupts. They are the data used for the current
 276  * request.
 277  */
 278 #define NO_TRACK 255
 279 
 280 static int read_track = 0;      /* flag to indicate if we want to read entire track */
 281 static int buffer_track = -1;
 282 static int buffer_drive = -1;
 283 static int cur_spec1 = -1;
 284 static int cur_rate = -1;
 285 static struct floppy_struct * floppy = floppy_type;
 286 static unsigned char current_drive = 255;
 287 static unsigned char sector = 0;
 288 static unsigned char head = 0;
 289 static unsigned char track = 0;
 290 static unsigned char seek_track = 0;
 291 static unsigned char current_track = NO_TRACK;
 292 static unsigned char command = 0;
 293 static unsigned char fdc_version = FDC_TYPE_STD;        /* FDC version code */
 294 
 295 static void floppy_ready(void);
 296 
 297 static void select_callback(unsigned long unused)
     /*  */
 298 {
 299         floppy_ready();
 300 }
 301 
 302 static void floppy_select(unsigned int nr)
     /*  */
 303 {
 304         static struct timer_list select = { NULL, 0, 0, select_callback };
 305 
 306         if (current_drive == (current_DOR & 3)) {
 307                 floppy_ready();
 308                 return;
 309         }
 310         seek = 1;
 311         current_track = NO_TRACK;
 312         current_DOR &= 0xFC;
 313         current_DOR |= current_drive;
 314         outb(current_DOR,FD_DOR);
 315         del_timer(&select);
 316         select.expires = 2;
 317         add_timer(&select);
 318 }
 319 
 320 static void motor_on_callback(unsigned long nr)
     /*  */
 321 {
 322         running |= 0x10 << nr;
 323         floppy_select(nr);
 324 }
 325 
 326 static struct timer_list motor_on_timer[4] = {
 327         { NULL, 0, 0, motor_on_callback },
 328         { NULL, 0, 1, motor_on_callback },
 329         { NULL, 0, 2, motor_on_callback },
 330         { NULL, 0, 3, motor_on_callback }
 331 };
 332 
 333 static void motor_off_callback(unsigned long nr)
     /*  */
 334 {
 335         unsigned char mask = ~(0x10 << nr);
 336         cli();
 337         running &= mask;
 338         current_DOR &= mask;
 339         outb(current_DOR,FD_DOR);
 340         sti();
 341 }
 342 
 343 static struct timer_list motor_off_timer[4] = {
 344         { NULL, 0, 0, motor_off_callback },
 345         { NULL, 0, 1, motor_off_callback },
 346         { NULL, 0, 2, motor_off_callback },
 347         { NULL, 0, 3, motor_off_callback }
 348 };
 349 
 350 static void floppy_on(unsigned int nr)
     /*  */
 351 {
 352         unsigned char mask = 0x10 << nr;
 353 
 354         del_timer(motor_off_timer + nr);
 355         if (mask & running)
 356                 floppy_select(nr);
 357         if (!(mask & current_DOR)) {
 358                 del_timer(motor_on_timer + nr);
 359                 motor_on_timer[nr].expires = HZ;
 360                 add_timer(motor_on_timer + nr);
 361         }
 362         current_DOR &= 0xFC;
 363         current_DOR |= mask;
 364         current_DOR |= nr;
 365         outb(current_DOR,FD_DOR);
 366 }
 367 
 368 static void floppy_off(unsigned int nr)
     /*  */
 369 {
 370         del_timer(motor_off_timer+nr);
 371         motor_off_timer[nr].expires = 3*HZ;
 372         add_timer(motor_off_timer+nr);
 373 }
 374 
 375 void request_done(int uptodate)
     /*  */
 376 {
 377         timer_active &= ~(1 << FLOPPY_TIMER);
 378         if (format_status != FORMAT_BUSY)
 379                 end_request(uptodate);
 380         else {
 381                 format_status = uptodate ? FORMAT_OKAY : FORMAT_ERROR;
 382                 wake_up(&format_done);
 383         }
 384 }
 385 
 386 /*
 387  * floppy-change is never called from an interrupt, so we can relax a bit
 388  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
 389  * to the desired drive, but it will probably not survive the sleep if
 390  * several floppies are used at the same time: thus the loop.
 391  */
 392 int floppy_change(struct buffer_head * bh)
     /*  */
 393 {
 394         unsigned int mask = 1 << (bh->b_dev & 0x03);
 395 
 396         if (MAJOR(bh->b_dev) != MAJOR_NR) {
 397                 printk("floppy_changed: not a floppy\n");
 398                 return 0;
 399         }
 400         if (fake_change & mask) {
 401                 buffer_track = -1;
 402                 fake_change &= ~mask;
 403 /* omitting the next line breaks formatting in a horrible way ... */
 404                 changed_floppies &= ~mask;
 405                 return 1;
 406         }
 407         if (changed_floppies & mask) {
 408                 buffer_track = -1;
 409                 changed_floppies &= ~mask;
 410                 recalibrate = 1;
 411                 return 1;
 412         }
 413         if (!bh)
 414                 return 0;
 415         if (bh->b_dirt)
 416                 ll_rw_block(WRITE, 1, &bh);
 417         else {
 418                 buffer_track = -1;
 419                 bh->b_uptodate = 0;
 420                 ll_rw_block(READ, 1, &bh);
 421         }
 422         cli();
 423         while (bh->b_lock)
 424                 sleep_on(&bh->b_wait);
 425         sti();
 426         if (changed_floppies & mask) {
 427                 changed_floppies &= ~mask;
 428                 recalibrate = 1;
 429                 return 1;
 430         }
 431         return 0;
 432 }
 433 
 434 #define copy_buffer(from,to) \
 435 __asm__("cld ; rep ; movsl" \
 436         : \
 437         :"c" (BLOCK_SIZE/4),"S" ((long)(from)),"D" ((long)(to)) \
 438         :"cx","di","si")
 439 
 440 static void setup_DMA(void)
     /*  */
 441 {
 442         unsigned long addr,count;
 443         unsigned char dma_code;
 444 
 445         dma_code = DMA_WRITE;
 446         if (command == FD_READ)
 447                 dma_code = DMA_READ;
 448         if (command == FD_FORMAT) {
 449                 addr = (long) tmp_floppy_area;
 450                 count = floppy->sect*4;
 451         } else {
 452                 addr = (long) CURRENT->buffer;
 453                 count = 1024;
 454         }
 455         if (read_track) {
 456 /* mark buffer-track bad, in case all this fails.. */
 457                 buffer_drive = buffer_track = -1;
 458                 count = floppy->sect*floppy->head*512;
 459                 addr = (long) floppy_track_buffer;
 460         } else if (addr >= LAST_DMA_ADDR) {
 461                 addr = (long) tmp_floppy_area;
 462                 if (command == FD_WRITE)
 463                         copy_buffer(CURRENT->buffer,tmp_floppy_area);
 464         }
 465         cli();
 466         disable_dma(FLOPPY_DMA);
 467         clear_dma_ff(FLOPPY_DMA);
 468         set_dma_mode(FLOPPY_DMA, (command == FD_READ)? DMA_MODE_READ : DMA_MODE_WRITE);
 469         set_dma_addr(FLOPPY_DMA, addr);
 470         set_dma_count(FLOPPY_DMA, count);
 471         enable_dma(FLOPPY_DMA);
 472         sti();
 473 }
 474 
 475 static void output_byte(char byte)
     /*  */
 476 {
 477         int counter;
 478         unsigned char status;
 479 
 480         if (reset)
 481                 return;
 482         for(counter = 0 ; counter < 10000 ; counter++) {
 483                 status = inb_p(FD_STATUS) & (STATUS_READY | STATUS_DIR);
 484                 if (status == STATUS_READY) {
 485                         outb(byte,FD_DATA);
 486                         return;
 487                 }
 488         }
 489         current_track = NO_TRACK;
 490         reset = 1;
 491         printk("Unable to send byte to FDC\n");
 492 }
 493 
 494 static int result(void)
     /*  */
 495 {
 496         int i = 0, counter, status;
 497 
 498         if (reset)
 499                 return -1;
 500         for (counter = 0 ; counter < 10000 ; counter++) {
 501                 status = inb_p(FD_STATUS)&(STATUS_DIR|STATUS_READY|STATUS_BUSY);
 502                 if (status == STATUS_READY) {
 503                         return i;
 504                 }
 505                 if (status == (STATUS_DIR|STATUS_READY|STATUS_BUSY)) {
 506                         if (i >= MAX_REPLIES) {
 507                                 printk("floppy_stat reply overrun\n");
 508                                 break;
 509                         }
 510                         reply_buffer[i++] = inb_p(FD_DATA);
 511                 }
 512         }
 513         reset = 1;
 514         current_track = NO_TRACK;
 515         printk("Getstatus times out\n");
 516         return -1;
 517 }
 518 
 519 static void bad_flp_intr(void)
     /*  */
 520 {
 521         int errors;
 522 
 523         current_track = NO_TRACK;
 524         if (format_status == FORMAT_BUSY)
 525                 errors = ++format_errors;
 526         else if (!CURRENT) {
 527                 printk(DEVICE_NAME ": no current request\n");
 528                 reset = recalibrate = 1;
 529                 return;
 530         } else
 531                 errors = ++CURRENT->errors;
 532         if (errors > MAX_ERRORS) {
 533                 request_done(0);
 534         }
 535         if (errors > MAX_ERRORS/2)
 536                 reset = 1;
 537         else
 538                 recalibrate = 1;
 539 }       
 540 
 541 
 542 /* Set perpendicular mode as required, based on data rate, if supported.
 543  * 82077 Untested! 1Mbps data rate only possible with 82077-1.
 544  * TODO: increase MAX_BUFFER_SECTORS, add floppy_type entries.
 545  */
 546 static inline void perpendicular_mode(unsigned char rate)
     /*  */
 547 {
 548         if (fdc_version == FDC_TYPE_82077) {
 549                 output_byte(FD_PERPENDICULAR);
 550                 if (rate & 0x40) {
 551                         unsigned char r = rate & 0x03;
 552                         if (r == 0)
 553                                 output_byte(2); /* perpendicular, 500 kbps */
 554                         else if (r == 3)
 555                                 output_byte(3); /* perpendicular, 1Mbps */
 556                         else {
 557                                 printk(DEVICE_NAME ": Invalid data rate for perpendicular mode!\n");
 558                                 reset = 1;
 559                         }
 560                 } else
 561                         output_byte(0);         /* conventional mode */
 562         } else {
 563                 if (rate & 0x40) {
 564                         printk(DEVICE_NAME ": perpendicular mode not supported by this FDC.\n");
 565                         reset = 1;
 566                 }
 567         }
 568 } /* perpendicular_mode */
 569 
 570 
 571 /*
 572  * This has only been tested for the case fdc_version == FDC_TYPE_STD.
 573  * In case you have a 82077 and want to test it, you'll have to compile
 574  * with `FDC_FIFO_UNTESTED' defined. You may also want to add support for
 575  * recognizing drives with vertical recording support.
 576  */
 577 static void configure_fdc_mode(void)
     /*  */
 578 {
 579         if (need_configure && (fdc_version == FDC_TYPE_82077)) {
 580                 /* Enhanced version with FIFO & vertical recording. */
 581                 output_byte(FD_CONFIGURE);
 582                 output_byte(0);
 583                 output_byte(0x1A);      /* FIFO on, polling off, 10 byte threshold */
 584                 output_byte(0);         /* precompensation from track 0 upwards */
 585                 need_configure = 0;
 586                 printk(DEVICE_NAME ": FIFO enabled\n");
 587         }
 588         if (cur_spec1 != floppy->spec1) {
 589                 cur_spec1 = floppy->spec1;
 590                 output_byte(FD_SPECIFY);
 591                 output_byte(cur_spec1);         /* hut etc */
 592                 output_byte(6);                 /* Head load time =6ms, DMA */
 593         }
 594         if (cur_rate != floppy->rate) {
 595                 /* use bit 6 of floppy->rate to indicate perpendicular mode */
 596                 perpendicular_mode(floppy->rate);
 597                 outb_p((cur_rate = (floppy->rate)) & ~0x40, FD_DCR);
 598         }
 599 } /* configure_fdc_mode */
 600 
 601 
 602 static void tell_sector(int nr)
     /*  */
 603 {
 604         if (nr!=7) {
 605                 printk(" -- FDC reply errror");
 606                 reset = 1;
 607         } else
 608                 printk(": track %d, head %d, sector %d", reply_buffer[3],
 609                         reply_buffer[4], reply_buffer[5]);
 610 } /* tell_sector */
 611 
 612 
 613 /*
 614  * Ok, this interrupt is called after a DMA read/write has succeeded
 615  * or failed, so we check the results, and copy any buffers.
 616  * hhb: Added better error reporting.
 617  */
 618 static void rw_interrupt(void)
     /*  */
 619 {
 620         char * buffer_area;
 621         int nr;
 622         char bad;
 623 
 624         nr = result();
 625         /* check IC to find cause of interrupt */
 626         switch ((ST0 & ST0_INTR)>>6) {
 627                 case 1: /* error occured during command execution */
 628                         bad = 1;
 629                         if (ST1 & ST1_WP) {
 630                                 printk(DEVICE_NAME ": Drive %d is write protected\n", current_drive);
 631                                 request_done(0);
 632                                 bad = 0;
 633                         } else if (ST1 & ST1_OR) {
 634                                 if (ftd_msg[ST0 & ST0_DS])
 635                                         printk(DEVICE_NAME ": Over/Underrun - retrying\n");
 636                                 /* could continue from where we stopped, but ... */
 637                                 bad = 0;
 638                         } else if (CURRENT_ERRORS > min_report_error_cnt[ST0 & ST0_DS]) {
 639                                 printk(DEVICE_NAME " %d: ", ST0 & ST0_DS);
 640                                 if (ST0 & ST0_ECE) {
 641                                         printk("Recalibrate failed!");
 642                                 } else if (ST2 & ST2_CRC) {
 643                                         printk("data CRC error");
 644                                         tell_sector(nr);
 645                                 } else if (ST1 & ST1_CRC) {
 646                                         printk("CRC error");
 647                                         tell_sector(nr);
 648                                 } else if ((ST1 & (ST1_MAM|ST1_ND)) || (ST2 & ST2_MAM)) {
 649                                         if (!probing) {
 650                                                 printk("sector not found");
 651                                                 tell_sector(nr);
 652                                         } else
 653                                                 printk("probe failed...");
 654                                 } else if (ST2 & ST2_WC) {      /* seek error */
 655                                         printk("wrong cylinder");
 656                                 } else if (ST2 & ST2_BC) {      /* cylinder marked as bad */
 657                                         printk("bad cylinder");
 658                                 } else {
 659                                         printk("unknown error. ST[0..3] are: 0x%x 0x%x 0x%x 0x%x\n", ST0, ST1, ST2, ST3);
 660                                 }
 661                                 printk("\n");
 662 
 663                         }
 664                         if (bad)
 665                                 bad_flp_intr();
 666                         redo_fd_request();
 667                         return;
 668                 case 2: /* invalid command given */
 669                         printk(DEVICE_NAME ": Invalid FDC command given!\n");
 670                         request_done(0);
 671                         return;
 672                 case 3:
 673                         printk(DEVICE_NAME ": Abnormal termination caused by polling\n");
 674                         bad_flp_intr();
 675                         redo_fd_request();
 676                         return;
 677                 default: /* (0) Normal command termination */
 678                         break;
 679         }
 680 
 681         if (probing) {
 682                 int drive = MINOR(CURRENT->dev);
 683 
 684                 if (ftd_msg[drive])
 685                         printk("Auto-detected floppy type %s in fd%d\n",
 686                             floppy->name,drive);
 687                 current_type[drive] = floppy;
 688                 floppy_sizes[drive] = floppy->size >> 1;
 689                 probing = 0;
 690         }
 691         if (read_track) {
 692                 buffer_track = seek_track;
 693                 buffer_drive = current_drive;
 694                 buffer_area = floppy_track_buffer +
 695                         ((sector-1 + head*floppy->sect)<<9);
 696                 copy_buffer(buffer_area,CURRENT->buffer);
 697         } else if (command == FD_READ &&
 698                 (unsigned long)(CURRENT->buffer) >= LAST_DMA_ADDR)
 699                 copy_buffer(tmp_floppy_area,CURRENT->buffer);
 700         request_done(1);
 701         redo_fd_request();
 702 }
 703 
 704 /*
 705  * We try to read tracks, but if we get too many errors, we
 706  * go back to reading just one sector at a time.
 707  *
 708  * This means we should be able to read a sector even if there
 709  * are other bad sectors on this track.
 710  */
 711 inline void setup_rw_floppy(void)
     /*  */
 712 {
 713         setup_DMA();
 714         do_floppy = rw_interrupt;
 715         output_byte(command);
 716         if (command != FD_FORMAT) {
 717                 if (read_track) {
 718                         output_byte(current_drive);
 719                         output_byte(track);
 720                         output_byte(0);
 721                         output_byte(1);
 722                 } else {
 723                         output_byte(head<<2 | current_drive);
 724                         output_byte(track);
 725                         output_byte(head);
 726                         output_byte(sector);
 727                 }
 728                 output_byte(2);         /* sector size = 512 */
 729                 output_byte(floppy->sect);
 730                 output_byte(floppy->gap);
 731                 output_byte(0xFF);      /* sector size (0xff when n!=0 ?) */
 732         } else {
 733                 output_byte(head<<2 | current_drive);
 734                 output_byte(2);
 735                 output_byte(floppy->sect);
 736                 output_byte(floppy->fmt_gap);
 737                 output_byte(FD_FILL_BYTE);
 738         }
 739         if (reset)
 740                 redo_fd_request();
 741 }
 742 
 743 /*
 744  * This is the routine called after every seek (or recalibrate) interrupt
 745  * from the floppy controller. Note that the "unexpected interrupt" routine
 746  * also does a recalibrate, but doesn't come here.
 747  */
 748 static void seek_interrupt(void)
     /*  */
 749 {
 750 /* sense drive status */
 751         output_byte(FD_SENSEI);
 752         if (result() != 2 || (ST0 & 0xF8) != 0x20 || ST1 != seek_track) {
 753                 printk(DEVICE_NAME ": seek failed\n");
 754                 recalibrate = 1;
 755                 bad_flp_intr();
 756                 redo_fd_request();
 757                 return;
 758         }
 759         current_track = ST1;
 760         setup_rw_floppy();
 761 }
 762 
 763 
 764 /*
 765  * This routine is called when everything should be correctly set up
 766  * for the transfer (ie floppy motor is on and the correct floppy is
 767  * selected).
 768  */
 769 static void transfer(void)
     /*  */
 770 {
 771         read_track = (command == FD_READ) && (CURRENT_ERRORS < 4) &&
 772             (floppy->sect <= MAX_BUFFER_SECTORS);
 773 
 774         configure_fdc_mode();
 775 
 776         if (reset) {
 777                 redo_fd_request();
 778                 return;
 779         }
 780         if (!seek) {
 781                 setup_rw_floppy();
 782                 return;
 783         }
 784 
 785         do_floppy = seek_interrupt;
 786         output_byte(FD_SEEK);
 787         if (read_track)
 788                 output_byte(current_drive);
 789         else
 790                 output_byte((head<<2) | current_drive);
 791         output_byte(seek_track);
 792         if (reset)
 793                 redo_fd_request();
 794 }
 795 
 796 /*
 797  * Special case - used after a unexpected interrupt (or reset)
 798  */
 799 
 800 static void recalibrate_floppy(void);
 801 
 802 static void recal_interrupt(void)
     /*  */
 803 {
 804         output_byte(FD_SENSEI);
 805         current_track = NO_TRACK;
 806         if (result()!=2 || (ST0 & 0xE0) == 0x60)
 807                 reset = 1;
 808 /* Recalibrate until track 0 is reached. Might help on some errors. */
 809         if ((ST0 & 0x10) == 0x10)
 810                 recalibrate_floppy();   /* FIXME: should limit nr of recalibrates */
 811         else
 812                 redo_fd_request();
 813 }
 814 
 815 static void unexpected_floppy_interrupt(void)
     /*  */
 816 {
 817         current_track = NO_TRACK;
 818         output_byte(FD_SENSEI);
 819         printk(DEVICE_NAME ": unexpected interrupt\n");
 820         if (result()!=2 || (ST0 & 0xE0) == 0x60)
 821                 reset = 1;
 822         else
 823                 recalibrate = 1;
 824 }
 825 
 826 static void recalibrate_floppy(void)
     /*  */
 827 {
 828         recalibrate = 0;
 829         current_track = 0;
 830         do_floppy = recal_interrupt;
 831         output_byte(FD_RECALIBRATE);
 832         output_byte(head<<2 | current_drive);
 833         if (reset)
 834                 redo_fd_request();
 835 }
 836 
 837 /*
 838  * Must do 4 FD_SENSEIs after reset because of ``drive polling''.
 839  */
 840 static void reset_interrupt(void)
     /*  */
 841 {
 842         short i;
 843 
 844         for (i=0; i<4; i++) {
 845                 output_byte(FD_SENSEI);
 846                 (void) result();
 847         }
 848         output_byte(FD_SPECIFY);
 849         output_byte(cur_spec1);         /* hut etc */
 850         output_byte(6);                 /* Head load time =6ms, DMA */
 851         configure_fdc_mode();           /* reprogram fdc */
 852         if (initial_reset_flag) {
 853                 initial_reset_flag = 0;
 854                 recalibrate = 1;
 855                 reset = 0;
 856                 return;
 857         }
 858         if (!recover)
 859                 redo_fd_request();
 860         else {
 861                 recalibrate_floppy();
 862                 recover = 0;
 863         }
 864 }
 865 
 866 /*
 867  * reset is done by pulling bit 2 of DOR low for a while.
 868  */
 869 static void reset_floppy(void)
     /*  */
 870 {
 871         int i;
 872 
 873         do_floppy = reset_interrupt;
 874         reset = 0;
 875         current_track = NO_TRACK;
 876         cur_spec1 = -1;
 877         cur_rate = -1;
 878         recalibrate = 1;
 879         need_configure = 1;
 880         if (!initial_reset_flag)
 881                 printk("Reset-floppy called\n");
 882         cli();
 883         outb_p(current_DOR & ~0x04, FD_DOR);
 884         for (i=0 ; i<1000 ; i++)
 885                 __asm__("nop");
 886         outb(current_DOR, FD_DOR);
 887         sti();
 888 }
 889 
 890 static void floppy_shutdown(void)
     /*  */
 891 {
 892         cli();
 893         do_floppy = NULL;
 894         request_done(0);
 895         recover = 1;
 896         reset_floppy();
 897         sti();
 898         redo_fd_request();
 899 }
 900 
 901 static void shake_done(void)
     /*  */
 902 {
 903         current_track = NO_TRACK;
 904         if (inb(FD_DIR) & 0x80)
 905                 request_done(0);
 906         redo_fd_request();
 907 }
 908 
 909 static int retry_recal(void (*proc)(void))
     /*  */
 910 {
 911         output_byte(FD_SENSEI);
 912         if (result() == 2 && (ST0 & 0x10) != 0x10) return 0;
 913         do_floppy = proc;
 914         output_byte(FD_RECALIBRATE);
 915         output_byte(head<<2 | current_drive);
 916         return 1;
 917 }
 918 
 919 static void shake_zero(void)
     /*  */
 920 {
 921         if (!retry_recal(shake_zero)) shake_done();
 922 }
 923 
 924 static void shake_one(void)
     /*  */
 925 {
 926         if (retry_recal(shake_one)) return;
 927         do_floppy = shake_done;
 928         output_byte(FD_SEEK);
 929         output_byte(head << 2 | current_drive);
 930         output_byte(1);
 931 }
 932 
 933 static void floppy_ready(void)
     /*  */
 934 {
 935         if (inb(FD_DIR) & 0x80) {
 936                 changed_floppies |= 1<<current_drive;
 937                 buffer_track = -1;
 938                 if (keep_data[current_drive]) {
 939                         if (keep_data[current_drive] > 0)
 940                                 keep_data[current_drive]--;
 941                 } else {
 942                         if (ftd_msg[current_drive] && current_type[current_drive] != NULL)
 943                                 printk("Disk type is undefined after disk "
 944                                     "change in fd%d\n",current_drive);
 945                         current_type[current_drive] = NULL;
 946                         floppy_sizes[current_drive] = MAX_DISK_SIZE;
 947                 }
 948 /* Forcing the drive to seek makes the "media changed" condition go away.
 949  * There should be a cleaner solution for that ...
 950  */
 951                 if (!reset && !recalibrate) {
 952                         if (current_track && current_track != NO_TRACK)
 953                                 do_floppy = shake_zero;
 954                         else
 955                                 do_floppy = shake_one;
 956                         output_byte(FD_RECALIBRATE);
 957                         output_byte(head<<2 | current_drive);
 958                         return;
 959                 }
 960         }
 961         if (reset) {
 962                 reset_floppy();
 963                 return;
 964         }
 965         if (recalibrate) {
 966                 recalibrate_floppy();
 967                 return;
 968         }
 969         transfer();
 970 }
 971 
 972 static void setup_format_params(void)
     /*  */
 973 {
 974     unsigned char *here = (unsigned char *) tmp_floppy_area;
 975     int count,head_shift,track_shift,total_shift;
 976 
 977     /* allow for about 30ms for data transport per track */
 978     head_shift  = floppy->sect / 6;
 979     /* a ``cylinder'' is two tracks plus a little stepping time */
 980     track_shift = 2 * head_shift + 1; 
 981     /* count backwards */
 982     total_shift = floppy->sect - 
 983         ((track_shift * track + head_shift * head) % floppy->sect);
 984 
 985     /* XXX: should do a check to see this fits in tmp_floppy_area!! */
 986     for (count = 0; count < floppy->sect; count++) {
 987         *here++ = track;
 988         *here++ = head;
 989         *here++ = 1 + (( count + total_shift ) % floppy->sect);
 990         *here++ = 2; /* 512 bytes */
 991     }
 992 }
 993 
 994 static void redo_fd_request(void)
     /*  */
 995 {
 996         unsigned int block;
 997         char * buffer_area;
 998         int device;
 999 
1000         if (CURRENT && CURRENT->dev < 0) return;
1001 
1002 repeat:
1003         if (format_status == FORMAT_WAIT)
1004                 format_status = FORMAT_BUSY;
1005         if (format_status != FORMAT_BUSY) {
1006                 if (!CURRENT) {
1007                         if (!fdc_busy)
1008                                 printk("FDC access conflict!");
1009                         fdc_busy = 0;
1010                         wake_up(&fdc_wait);
1011                         CLEAR_INTR;
1012                         return;
1013                 }
1014                 if (MAJOR(CURRENT->dev) != MAJOR_NR)
1015                         panic(DEVICE_NAME ": request list destroyed"); \
1016                 if (CURRENT->bh) {
1017                         if (!CURRENT->bh->b_lock)
1018                                 panic(DEVICE_NAME ": block not locked");
1019                 }
1020         }
1021         seek = 0;
1022         probing = 0;
1023         device = MINOR(CURRENT_DEVICE);
1024         if (device > 3)
1025                 floppy = (device >> 2) + floppy_type;
1026         else { /* Auto-detection */
1027                 floppy = current_type[device & 3];
1028                 if (!floppy) {
1029                         probing = 1;
1030                         floppy = base_type[device & 3];
1031                         if (!floppy) {
1032                                 request_done(0);
1033                                 goto repeat;
1034                         }
1035                         if (CURRENT_ERRORS & 1)
1036                                 floppy++;
1037                 }
1038         }
1039         if (format_status != FORMAT_BUSY) {
1040                 if (current_drive != CURRENT_DEV) {
1041                         current_track = NO_TRACK;
1042                         current_drive = CURRENT_DEV;
1043                 }
1044                 block = CURRENT->sector;
1045                 if (block+2 > floppy->size) {
1046                         request_done(0);
1047                         goto repeat;
1048                 }
1049                 sector = block % floppy->sect;
1050                 block /= floppy->sect;
1051                 head = block % floppy->head;
1052                 track = block / floppy->head;
1053                 seek_track = track << floppy->stretch;
1054                 if (CURRENT->cmd == READ)
1055                         command = FD_READ;
1056                 else if (CURRENT->cmd == WRITE)
1057                         command = FD_WRITE;
1058                 else {
1059                         printk("do_fd_request: unknown command\n");
1060                         request_done(0);
1061                         goto repeat;
1062                 }
1063         } else {
1064                 if (current_drive != (format_req.device & 3))
1065                         current_track = NO_TRACK;
1066                 current_drive = format_req.device & 3;
1067                 if (((unsigned) format_req.track) >= floppy->track ||
1068                     (format_req.head & 0xfffe) || probing) {
1069                         request_done(0);
1070                         goto repeat;
1071                 }
1072                 head = format_req.head;
1073                 track = format_req.track;
1074                 seek_track = track << floppy->stretch;
1075                 if (seek_track == buffer_track) buffer_track = -1;
1076                 command = FD_FORMAT;
1077                 setup_format_params();
1078         }
1079         timer_table[FLOPPY_TIMER].expires = jiffies+10*HZ;
1080         timer_active |= 1 << FLOPPY_TIMER;
1081         if ((seek_track == buffer_track) &&
1082          (current_drive == buffer_drive)) {
1083                 buffer_area = floppy_track_buffer +
1084                         ((sector + head*floppy->sect)<<9);
1085                 if (command == FD_READ) {
1086                         copy_buffer(buffer_area,CURRENT->buffer);
1087                         request_done(1);
1088                         goto repeat;
1089                 } else if (command == FD_WRITE)
1090                         copy_buffer(CURRENT->buffer,buffer_area);
1091         }
1092         if (seek_track != current_track)
1093                 seek = 1;
1094         sector++;
1095         del_timer(motor_off_timer + current_drive);
1096         floppy_on(current_drive);
1097 }
1098 
1099 void do_fd_request(void)
     /*  */
1100 {
1101         cli();
1102         while (fdc_busy) sleep_on(&fdc_wait);
1103         fdc_busy = 1;
1104         sti();
1105         redo_fd_request();
1106 }
1107 
1108 static int fd_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
     /*  */
1109     unsigned long param)
1110 {
1111         int i,drive,cnt,okay;
1112         struct floppy_struct *this_floppy;
1113 
1114         switch (cmd) {
1115                 RO_IOCTLS(inode->i_rdev,param);
1116         }
1117         drive = MINOR(inode->i_rdev);
1118         switch (cmd) {
1119                 case FDFMTBEG:
1120                         if (!suser())
1121                                 return -EPERM;
1122                         return 0;
1123                 case FDFMTEND:
1124                         if (!suser())
1125                                 return -EPERM;
1126                         cli();
1127                         fake_change |= 1 << (drive & 3);
1128                         sti();
1129                         drive &= 3;
1130                         cmd = FDCLRPRM;
1131                         break;
1132                 case FDGETPRM:
1133                         if (drive > 3) this_floppy = &floppy_type[drive >> 2];
1134                         else if ((this_floppy = current_type[drive & 3]) == NULL)
1135                                     return -ENODEV;
1136                         i = verify_area(VERIFY_WRITE,(void *) param,sizeof(struct floppy_struct));
1137                         if (i)
1138                                 return i;
1139                         for (cnt = 0; cnt < sizeof(struct floppy_struct); cnt++)
1140                                 put_fs_byte(((char *) this_floppy)[cnt],
1141                                     (char *) param+cnt);
1142                         return 0;
1143                 case FDFMTTRK:
1144                         if (!suser())
1145                                 return -EPERM;
1146                         if (fd_ref[drive & 3] != 1)
1147                                 return -EBUSY;
1148                         cli();
1149                         while (format_status != FORMAT_NONE)
1150                                 sleep_on(&format_done);
1151                         for (cnt = 0; cnt < sizeof(struct format_descr); cnt++)
1152                                 ((char *) &format_req)[cnt] = get_fs_byte(
1153                                     (char *) param+cnt);
1154                         format_req.device = drive;
1155                         format_status = FORMAT_WAIT;
1156                         format_errors = 0;
1157                         while (format_status != FORMAT_OKAY && format_status !=
1158                             FORMAT_ERROR) {
1159                                 if (fdc_busy) sleep_on(&fdc_wait);
1160                                 else {
1161                                         fdc_busy = 1;
1162                                         redo_fd_request();
1163                                 }
1164                         }
1165                         while (format_status != FORMAT_OKAY && format_status !=
1166                             FORMAT_ERROR)
1167                                 sleep_on(&format_done);
1168                         sti();
1169                         okay = format_status == FORMAT_OKAY;
1170                         format_status = FORMAT_NONE;
1171                         floppy_off(drive & 3);
1172                         wake_up(&format_done);
1173                         return okay ? 0 : -EIO;
1174                 case FDFLUSH:
1175                         if (!permission(inode, 2))
1176                                 return -EPERM;
1177                         cli();
1178                         fake_change |= 1 << (drive & 3);
1179                         sti();
1180                         check_disk_change(inode->i_rdev);
1181                         return 0;
1182         }
1183         if (!suser())
1184                 return -EPERM;
1185         if (drive < 0 || drive > 3)
1186                 return -EINVAL;
1187         switch (cmd) {
1188                 case FDCLRPRM:
1189                         current_type[drive] = NULL;
1190                         floppy_sizes[drive] = MAX_DISK_SIZE;
1191                         keep_data[drive] = 0;
1192                         break;
1193                 case FDSETPRM:
1194                 case FDDEFPRM:
1195                         memcpy_fromfs(user_params+drive,
1196                                 (void *) param,
1197                                 sizeof(struct floppy_struct));
1198                         current_type[drive] = &user_params[drive];
1199                         floppy_sizes[drive] = user_params[drive].size >> 1;
1200                         if (cmd == FDDEFPRM)
1201                                 keep_data[drive] = -1;
1202                         else {
1203                                 cli();
1204                                 while (fdc_busy) sleep_on(&fdc_wait);
1205                                 fdc_busy = 1;
1206                                 sti();
1207                                 outb_p((current_DOR & 0xfc) | drive |
1208                                     (0x10 << drive),FD_DOR);
1209                                 for (cnt = 0; cnt < 1000; cnt++) __asm__("nop");
1210                                 if (inb(FD_DIR) & 0x80)
1211                                         keep_data[drive] = 1;
1212                                 else
1213                                         keep_data[drive] = 0;
1214                                 outb_p(current_DOR,FD_DOR);
1215                                 fdc_busy = 0;
1216                                 wake_up(&fdc_wait);
1217                         }
1218                         break;
1219                 case FDMSGON:
1220                         ftd_msg[drive] = 1;
1221                         break;
1222                 case FDMSGOFF:
1223                         ftd_msg[drive] = 0;
1224                         break;
1225                 case FDSETEMSGTRESH:
1226                         min_report_error_cnt[drive] = (unsigned short) (param & 0x0f);
1227                         break;
1228                 default:
1229                         return -EINVAL;
1230         }
1231         return 0;
1232 }
1233 
1234 #define CMOS_READ(addr) ({ \
1235 outb_p(addr,0x70); \
1236 inb_p(0x71); \
1237 })
1238 
1239 static struct floppy_struct *find_base(int drive,int code)
     /*  */
1240 {
1241         struct floppy_struct *base;
1242 
1243         if (code > 0 && code < 5) {
1244                 base = &floppy_types[(code-1)*2];
1245                 printk("fd%d is %s",drive,base->name);
1246                 return base;
1247         }
1248         printk("fd%d is unknown type %d",drive,code);
1249         return NULL;
1250 }
1251 
1252 static void config_types(void)
     /*  */
1253 {
1254         printk("Floppy drive(s): ");
1255         base_type[0] = find_base(0,(CMOS_READ(0x10) >> 4) & 15);
1256         if (((CMOS_READ(0x14) >> 6) & 1) == 0)
1257                 base_type[1] = NULL;
1258         else {
1259                 printk(", ");
1260                 base_type[1] = find_base(1,CMOS_READ(0x10) & 15);
1261         }
1262         base_type[2] = base_type[3] = NULL;
1263         printk("\n");
1264 }
1265 
1266 /*
1267  * floppy_open check for aliasing (/dev/fd0 can be the same as
1268  * /dev/PS0 etc), and disallows simultaneous access to the same
1269  * drive with different device numbers.
1270  */
1271 static int floppy_open(struct inode * inode, struct file * filp)
     /*  */
1272 {
1273         int drive;
1274         int old_dev;
1275 
1276         drive = inode->i_rdev & 3;
1277         old_dev = fd_device[drive];
1278         if (fd_ref[drive])
1279                 if (old_dev != inode->i_rdev)
1280                         return -EBUSY;
1281         fd_ref[drive]++;
1282         fd_device[drive] = inode->i_rdev;
1283         buffer_drive = buffer_track = -1;
1284         if (old_dev && old_dev != inode->i_rdev)
1285                 invalidate_buffers(old_dev);
1286         if (filp && filp->f_mode)
1287                 check_disk_change(inode->i_rdev);
1288         return 0;
1289 }
1290 
1291 static void floppy_release(struct inode * inode, struct file * filp)
     /*  */
1292 {
1293         sync_dev(inode->i_rdev);
1294         if (!fd_ref[inode->i_rdev & 3]--) {
1295                 printk("floppy_release with fd_ref == 0");
1296                 fd_ref[inode->i_rdev & 3] = 0;
1297         }
1298 }
1299 
1300 static struct file_operations floppy_fops = {
1301         NULL,                   /* lseek - default */
1302         block_read,             /* read - general block-dev read */
1303         block_write,            /* write - general block-dev write */
1304         NULL,                   /* readdir - bad */
1305         NULL,                   /* select */
1306         fd_ioctl,               /* ioctl */
1307         NULL,                   /* mmap */
1308         floppy_open,            /* open */
1309         floppy_release,         /* release */
1310         block_fsync             /* fsync */
1311 };
1312 
1313 
1314 /*
1315  * The version command is not supposed to generate an interrupt, but
1316  * my FDC does, except when booting in SVGA screen mode.
1317  * When it does generate an interrupt, it doesn't return any status bytes.
1318  * It appears to have something to do with the version command...
1319  *
1320  * This should never be called, because of the reset after the version check.
1321  */
1322 static void ignore_interrupt(void)
     /*  */
1323 {
1324         printk(DEVICE_NAME ": weird interrupt ignored (%d)\n", result());
1325         reset = 1;
1326         CLEAR_INTR;     /* ignore only once */
1327 }
1328 
1329 
1330 static void floppy_interrupt(int unused)
     /*  */
1331 {
1332         void (*handler)(void) = DEVICE_INTR;
1333 
1334         DEVICE_INTR = NULL;
1335         if (!handler)
1336                 handler = unexpected_floppy_interrupt;
1337         handler();
1338 }
1339 
1340 /*
1341  * This is the floppy IRQ description. The SA_INTERRUPT in sa_flags
1342  * means we run the IRQ-handler with interrupts disabled.
1343  */
1344 static struct sigaction floppy_sigaction = {
1345         floppy_interrupt,
1346         0,
1347         SA_INTERRUPT,
1348         NULL
1349 };
1350 
1351 void floppy_init(void)
     /*  */
1352 {
1353         outb(current_DOR,FD_DOR);
1354         if (register_blkdev(MAJOR_NR,"fd",&floppy_fops)) {
1355                 printk("Unable to get major %d for floppy\n",MAJOR_NR);
1356                 return;
1357         }
1358         blk_size[MAJOR_NR] = floppy_sizes;
1359         blk_dev[MAJOR_NR].request_fn = DEVICE_REQUEST;
1360         timer_table[FLOPPY_TIMER].fn = floppy_shutdown;
1361         timer_active &= ~(1 << FLOPPY_TIMER);
1362         config_types();
1363         if (irqaction(FLOPPY_IRQ,&floppy_sigaction))
1364                 printk("Unable to grab IRQ%d for the floppy driver\n", FLOPPY_IRQ);
1365         if (request_dma(FLOPPY_DMA))
1366                 printk("Unable to grab DMA%d for the floppy driver\n", FLOPPY_DMA);
1367         /* Try to determine the floppy controller type */
1368         DEVICE_INTR = ignore_interrupt; /* don't ask ... */
1369         output_byte(FD_VERSION);        /* get FDC version code */
1370         if (result() != 1) {
1371                 printk(DEVICE_NAME ": FDC failed to return version byte\n");
1372                 fdc_version = FDC_TYPE_STD;
1373         } else
1374                 fdc_version = reply_buffer[0];
1375         if (fdc_version != FDC_TYPE_STD) 
1376                 printk(DEVICE_NAME ": FDC version 0x%x\n", fdc_version);
1377 #ifndef FDC_FIFO_UNTESTED
1378         fdc_version = FDC_TYPE_STD;     /* force std fdc type; can't test other. */
1379 #endif
1380 
1381         /* Not all FDCs seem to be able to handle the version command
1382          * properly, so force a reset for the standard FDC clones,
1383          * to avoid interrupt garbage.
1384          */
1385 
1386         if (fdc_version == FDC_TYPE_STD) {
1387                 initial_reset_flag = 1;
1388                 reset_floppy();
1389         }
1390 }
/* */
root/drivers/block/floppy.c

DEFINITIONS
