kernel/blk_drv/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 2
  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 #define LAST_DMA_ADDR   (0x1000000 - BLOCK_SIZE)
 126 
 127 /*
 128  * globals used by 'result()'
 129  */
 130 #define MAX_REPLIES 7
 131 static unsigned char reply_buffer[MAX_REPLIES];
 132 #define ST0 (reply_buffer[0])
 133 #define ST1 (reply_buffer[1])
 134 #define ST2 (reply_buffer[2])
 135 #define ST3 (reply_buffer[3])
 136 
 137 /*
 138  * This struct defines the different floppy types.
 139  *
 140  * The 'stretch' tells if the tracks need to be doubled for some
 141  * types (ie 360kB diskette in 1.2MB drive etc). Others should
 142  * be self-explanatory.
 143  */
 144 static struct floppy_struct floppy_type[] = {
 145         {    0, 0,0, 0,0,0x00,0x00,0x00,0x00,NULL },    /* no testing */
 146         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,NULL },    /* 360kB PC diskettes */
 147         { 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,NULL },    /* 1.2 MB AT-diskettes */
 148         {  720, 9,2,40,1,0x2A,0x02,0xDF,0x50,NULL },    /* 360kB in 720kB drive */
 149         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,NULL },    /* 3.5" 720kB diskette */
 150         {  720, 9,2,40,1,0x23,0x01,0xDF,0x50,NULL },    /* 360kB in 1.2MB drive */
 151         { 1440, 9,2,80,0,0x23,0x01,0xDF,0x50,NULL },    /* 720kB in 1.2MB drive */
 152         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL },    /* 1.44MB diskette */
 153 };
 154 
 155 /*
 156  * Auto-detection. Each drive type has a pair of formats which are
 157  * used in succession to try to read the disk. If the FDC cannot lock onto
 158  * the disk, the next format is tried. This uses the variable 'probing'.
 159  */
 160 static struct floppy_struct floppy_types[] = {
 161         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"360k/PC" }, /* 360kB PC diskettes */
 162         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"360k/PC" }, /* 360kB PC diskettes */
 163         { 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,"1.2M" },    /* 1.2 MB AT-diskettes */
 164         {  720, 9,2,40,1,0x23,0x01,0xDF,0x50,"360k/AT" }, /* 360kB in 1.2MB drive */
 165         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k" },    /* 3.5" 720kB diskette */
 166         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k" },    /* 3.5" 720kB diskette */
 167         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,"1.44M" },   /* 1.44MB diskette */
 168         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"720k/AT" }, /* 3.5" 720kB diskette */
 169 };
 170 
 171 /* Auto-detection: Disk type used until the next media change occurs. */
 172 struct floppy_struct *current_type[4] = { NULL, NULL, NULL, NULL };
 173 
 174 /* This type is tried first. */
 175 struct floppy_struct *base_type[4];
 176 
 177 /*
 178  * User-provided type information. current_type points to
 179  * the respective entry of this array.
 180  */
 181 struct floppy_struct user_params[4];
 182 
 183 static int floppy_sizes[] ={
 184         MAX_DISK_SIZE, MAX_DISK_SIZE, MAX_DISK_SIZE, MAX_DISK_SIZE,
 185          360, 360 ,360, 360,
 186         1200,1200,1200,1200,
 187          360, 360, 360, 360,
 188          720, 720, 720, 720,
 189          360, 360, 360, 360,
 190          720, 720, 720, 720,
 191         1440,1440,1440,1440
 192 };
 193 
 194 /*
 195  * The driver is trying to determine the correct media format
 196  * while probing is set. rw_interrupt() clears it after a
 197  * successful access.
 198  */
 199 static int probing = 0;
 200 
 201 /*
 202  * (User-provided) media information is _not_ discarded after a media change
 203  * if the corresponding keep_data flag is non-zero. Positive values are
 204  * decremented after each probe.
 205  */
 206 static int keep_data[4] = { 0,0,0,0 };
 207 
 208 /*
 209  * Announce successful media type detection and media information loss after
 210  * disk changes.
 211  * Also used to enable/disable printing of overrun warnings.
 212  */
 213 static ftd_msg[4] = { 0,0,0,0 };
 214 
 215 /* Prevent "aliased" accesses. */
 216 
 217 static fd_ref[4] = { 0,0,0,0 };
 218 static fd_device[4] = { 0,0,0,0 };
 219 
 220 /* Synchronization of FDC access. */
 221 static volatile int format_status = FORMAT_NONE, fdc_busy = 0;
 222 static struct wait_queue *fdc_wait = NULL, *format_done = NULL;
 223 
 224 /* Errors during formatting are counted here. */
 225 static int format_errors;
 226 
 227 /* Format request descriptor. */
 228 static struct format_descr format_req;
 229 
 230 /*
 231  * Current device number. Taken either from the block header or from the
 232  * format request descriptor.
 233  */
 234 #define CURRENT_DEVICE (format_status == FORMAT_BUSY ? format_req.device : \
 235    (CURRENT->dev))
 236 
 237 /* Current error count. */
 238 #define CURRENT_ERRORS (format_status == FORMAT_BUSY ? format_errors : \
 239     (CURRENT->errors))
 240 
 241 /*
 242  * Threshold for reporting FDC errors to the console.
 243  * Setting this to zero may flood your screen when using
 244  * ultra cheap floppies ;-)
 245  */
 246 static unsigned short min_report_error_cnt[4] = {2, 2, 2, 2};
 247 
 248 /*
 249  * Rate is 0 for 500kb/s, 1 for 300kbps, 2 for 250kbps
 250  * Spec1 is 0xSH, where S is stepping rate (F=1ms, E=2ms, D=3ms etc),
 251  * H is head unload time (1=16ms, 2=32ms, etc)
 252  *
 253  * Spec2 is (HLD<<1 | ND), where HLD is head load time (1=2ms, 2=4 ms etc)
 254  * and ND is set means no DMA. Hardcoded to 6 (HLD=6ms, use DMA).
 255  */
 256 
 257 /*
 258  * Track buffer and block buffer (in case track buffering doesn't work).
 259  * Because these are written to by the DMA controller, they must
 260  * not contain a 64k byte boundary crossing, or data will be
 261  * corrupted/lost. Alignment of these is enforced in boot/head.s.
 262  * Note that you must not change the sizes below without updating head.s.
 263  */
 264 extern char tmp_floppy_area[BLOCK_SIZE];
 265 extern char floppy_track_buffer[512*2*MAX_BUFFER_SECTORS];
 266 
 267 static void redo_fd_request(void);
 268 
 269 /*
 270  * These are global variables, as that's the easiest way to give
 271  * information to interrupts. They are the data used for the current
 272  * request.
 273  */
 274 #define NO_TRACK 255
 275 
 276 static int read_track = 0;      /* flag to indicate if we want to read entire track */
 277 static int buffer_track = -1;
 278 static int buffer_drive = -1;
 279 static int cur_spec1 = -1;
 280 static int cur_rate = -1;
 281 static struct floppy_struct * floppy = floppy_type;
 282 static unsigned char current_drive = 255;
 283 static unsigned char sector = 0;
 284 static unsigned char head = 0;
 285 static unsigned char track = 0;
 286 static unsigned char seek_track = 0;
 287 static unsigned char current_track = NO_TRACK;
 288 static unsigned char command = 0;
 289 static unsigned char fdc_version = FDC_TYPE_STD;        /* FDC version code */
 290 
 291 static void floppy_ready(void);
 292 
 293 static void select_callback(unsigned long unused)
     /*  */
 294 {
 295         floppy_ready();
 296 }
 297 
 298 static void floppy_select(unsigned int nr)
     /*  */
 299 {
 300         static struct timer_list select = { NULL, 0, 0, select_callback };
 301 
 302         if (current_drive == (current_DOR & 3)) {
 303                 floppy_ready();
 304                 return;
 305         }
 306         seek = 1;
 307         current_track = NO_TRACK;
 308         current_DOR &= 0xFC;
 309         current_DOR |= current_drive;
 310         outb(current_DOR,FD_DOR);
 311         del_timer(&select);
 312         select.expires = 2;
 313         add_timer(&select);
 314 }
 315 
 316 static void motor_on_callback(unsigned long nr)
     /*  */
 317 {
 318         running |= 0x10 << nr;
 319         floppy_select(nr);
 320 }
 321 
 322 static struct timer_list motor_on_timer[4] = {
 323         { NULL, 0, 0, motor_on_callback },
 324         { NULL, 0, 1, motor_on_callback },
 325         { NULL, 0, 2, motor_on_callback },
 326         { NULL, 0, 3, motor_on_callback }
 327 };
 328 
 329 static void motor_off_callback(unsigned long nr)
     /*  */
 330 {
 331         unsigned char mask = ~(0x10 << nr);
 332         cli();
 333         running &= mask;
 334         current_DOR &= mask;
 335         outb(current_DOR,FD_DOR);
 336         sti();
 337 }
 338 
 339 static struct timer_list motor_off_timer[4] = {
 340         { NULL, 0, 0, motor_off_callback },
 341         { NULL, 0, 1, motor_off_callback },
 342         { NULL, 0, 2, motor_off_callback },
 343         { NULL, 0, 3, motor_off_callback }
 344 };
 345 
 346 static void floppy_on(unsigned int nr)
     /*  */
 347 {
 348         unsigned char mask = 0x10 << nr;
 349 
 350         del_timer(motor_off_timer + nr);
 351         if (mask & running)
 352                 floppy_select(nr);
 353         if (!(mask & current_DOR)) {
 354                 del_timer(motor_on_timer + nr);
 355                 motor_on_timer[nr].expires = HZ;
 356                 add_timer(motor_on_timer + nr);
 357         }
 358         current_DOR &= 0xFC;
 359         current_DOR |= mask;
 360         current_DOR |= nr;
 361         outb(current_DOR,FD_DOR);
 362 }
 363 
 364 static void floppy_off(unsigned int nr)
     /*  */
 365 {
 366         del_timer(motor_off_timer+nr);
 367         motor_off_timer[nr].expires = 3*HZ;
 368         add_timer(motor_off_timer+nr);
 369 }
 370 
 371 void request_done(int uptodate)
     /*  */
 372 {
 373         timer_active &= ~(1 << FLOPPY_TIMER);
 374         if (format_status != FORMAT_BUSY)
 375                 end_request(uptodate);
 376         else {
 377                 format_status = uptodate ? FORMAT_OKAY : FORMAT_ERROR;
 378                 wake_up(&format_done);
 379         }
 380 }
 381 
 382 /*
 383  * floppy-change is never called from an interrupt, so we can relax a bit
 384  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
 385  * to the desired drive, but it will probably not survive the sleep if
 386  * several floppies are used at the same time: thus the loop.
 387  */
 388 int floppy_change(struct buffer_head * bh)
     /*  */
 389 {
 390         unsigned int mask = 1 << (bh->b_dev & 0x03);
 391 
 392         if (MAJOR(bh->b_dev) != 2) {
 393                 printk("floppy_changed: not a floppy\n");
 394                 return 0;
 395         }
 396         if (fake_change & mask) {
 397                 fake_change &= ~mask;
 398 /* omitting the next line breaks formatting in a horrible way ... */
 399                 changed_floppies &= ~mask;
 400                 return 1;
 401         }
 402         if (changed_floppies & mask) {
 403                 changed_floppies &= ~mask;
 404                 recalibrate = 1;
 405                 return 1;
 406         }
 407         if (!bh)
 408                 return 0;
 409         if (bh->b_dirt)
 410                 ll_rw_block(WRITE, 1, &bh);
 411         else {
 412                 buffer_track = -1;
 413                 bh->b_uptodate = 0;
 414                 ll_rw_block(READ, 1, &bh);
 415         }
 416         cli();
 417         while (bh->b_lock)
 418                 sleep_on(&bh->b_wait);
 419         sti();
 420         if (changed_floppies & mask) {
 421                 changed_floppies &= ~mask;
 422                 recalibrate = 1;
 423                 return 1;
 424         }
 425         return 0;
 426 }
 427 
 428 #define copy_buffer(from,to) \
 429 __asm__("cld ; rep ; movsl" \
 430         : \
 431         :"c" (BLOCK_SIZE/4),"S" ((long)(from)),"D" ((long)(to)) \
 432         :"cx","di","si")
 433 
 434 static void setup_DMA(void)
     /*  */
 435 {
 436         unsigned long addr,count;
 437         unsigned char dma_code;
 438 
 439         dma_code = DMA_WRITE;
 440         if (command == FD_READ)
 441                 dma_code = DMA_READ;
 442         if (command == FD_FORMAT) {
 443                 addr = (long) tmp_floppy_area;
 444                 count = floppy->sect*4;
 445         } else {
 446                 addr = (long) CURRENT->buffer;
 447                 count = 1024;
 448         }
 449         if (read_track) {
 450 /* mark buffer-track bad, in case all this fails.. */
 451                 buffer_drive = buffer_track = -1;
 452                 count = floppy->sect*2*512;
 453                 addr = (long) floppy_track_buffer;
 454         } else if (addr >= LAST_DMA_ADDR) {
 455                 addr = (long) tmp_floppy_area;
 456                 if (command == FD_WRITE)
 457                         copy_buffer(CURRENT->buffer,tmp_floppy_area);
 458         }
 459         cli();
 460         disable_dma(FLOPPY_DMA);
 461         clear_dma_ff(FLOPPY_DMA);
 462         set_dma_mode(FLOPPY_DMA, (command == FD_READ)? DMA_MODE_READ : DMA_MODE_WRITE);
 463         set_dma_addr(FLOPPY_DMA, addr);
 464         set_dma_count(FLOPPY_DMA, count);
 465         enable_dma(FLOPPY_DMA);
 466         sti();
 467 }
 468 
 469 static void output_byte(char byte)
     /*  */
 470 {
 471         int counter;
 472         unsigned char status;
 473 
 474         if (reset)
 475                 return;
 476         for(counter = 0 ; counter < 10000 ; counter++) {
 477                 status = inb_p(FD_STATUS) & (STATUS_READY | STATUS_DIR);
 478                 if (status == STATUS_READY) {
 479                         outb(byte,FD_DATA);
 480                         return;
 481                 }
 482         }
 483         current_track = NO_TRACK;
 484         reset = 1;
 485         printk("Unable to send byte to FDC\n");
 486 }
 487 
 488 static int result(void)
     /*  */
 489 {
 490         int i = 0, counter, status;
 491 
 492         if (reset)
 493                 return -1;
 494         for (counter = 0 ; counter < 10000 ; counter++) {
 495                 status = inb_p(FD_STATUS)&(STATUS_DIR|STATUS_READY|STATUS_BUSY);
 496                 if (status == STATUS_READY) {
 497                         return i;
 498                 }
 499                 if (status == (STATUS_DIR|STATUS_READY|STATUS_BUSY)) {
 500                         if (i >= MAX_REPLIES) {
 501                                 printk("floppy_stat reply overrun\n");
 502                                 break;
 503                         }
 504                         reply_buffer[i++] = inb_p(FD_DATA);
 505                 }
 506         }
 507         reset = 1;
 508         current_track = NO_TRACK;
 509         printk("Getstatus times out\n");
 510         return -1;
 511 }
 512 
 513 static void bad_flp_intr(void)
     /*  */
 514 {
 515         int errors;
 516 
 517         current_track = NO_TRACK;
 518         if (format_status == FORMAT_BUSY)
 519                 errors = ++format_errors;
 520         else if (!CURRENT) {
 521                 printk(DEVICE_NAME ": no current request\n");
 522                 reset = recalibrate = 1;
 523                 return;
 524         } else
 525                 errors = ++CURRENT->errors;
 526         if (errors > MAX_ERRORS) {
 527                 request_done(0);
 528         }
 529         if (errors > MAX_ERRORS/2)
 530                 reset = 1;
 531         else
 532                 recalibrate = 1;
 533 }       
 534 
 535 
 536 /* Set perpendicular mode as required, based on data rate, if supported.
 537  * 82077 Untested! 1Mbps data rate only possible with 82077-1.
 538  * TODO: increase MAX_BUFFER_SECTORS, add floppy_type entries.
 539  */
 540 static inline void perpendicular_mode(unsigned char rate)
     /*  */
 541 {
 542         if (fdc_version == FDC_TYPE_82077) {
 543                 output_byte(FD_PERPENDICULAR);
 544                 if (rate & 0x40) {
 545                         unsigned char r = rate & 0x03;
 546                         if (r == 0)
 547                                 output_byte(2); /* perpendicular, 500 kbps */
 548                         else if (r == 3)
 549                                 output_byte(3); /* perpendicular, 1Mbps */
 550                         else {
 551                                 printk(DEVICE_NAME ": Invalid data rate for perpendicular mode!\n");
 552                                 reset = 1;
 553                         }
 554                 } else
 555                         output_byte(0);         /* conventional mode */
 556         } else {
 557                 if (rate & 0x40) {
 558                         printk(DEVICE_NAME ": perpendicular mode not supported by this FDC.\n");
 559                         reset = 1;
 560                 }
 561         }
 562 } /* perpendicular_mode */
 563 
 564 
 565 /*
 566  * This has only been tested for the case fdc_version == FDC_TYPE_STD.
 567  * In case you have a 82077 and want to test it, you'll have to compile
 568  * with `FDC_FIFO_UNTESTED' defined. You may also want to add support for
 569  * recognizing drives with vertical recording support.
 570  */
 571 static void configure_fdc_mode(void)
     /*  */
 572 {
 573         if (need_configure && (fdc_version == FDC_TYPE_82077)) {
 574                 /* Enhanced version with FIFO & vertical recording. */
 575                 output_byte(FD_CONFIGURE);
 576                 output_byte(0);
 577                 output_byte(0x1A);      /* FIFO on, polling off, 10 byte threshold */
 578                 output_byte(0);         /* precompensation from track 0 upwards */
 579                 need_configure = 0;
 580                 printk(DEVICE_NAME ": FIFO enabled\n");
 581         }
 582         if (cur_spec1 != floppy->spec1) {
 583                 cur_spec1 = floppy->spec1;
 584                 output_byte(FD_SPECIFY);
 585                 output_byte(cur_spec1);         /* hut etc */
 586                 output_byte(6);                 /* Head load time =6ms, DMA */
 587         }
 588         if (cur_rate != floppy->rate) {
 589                 /* use bit 6 of floppy->rate to indicate perpendicular mode */
 590                 perpendicular_mode(floppy->rate);
 591                 outb_p((cur_rate = (floppy->rate)) & ~0x40, FD_DCR);
 592         }
 593 } /* configure_fdc_mode */
 594 
 595 
 596 static void tell_sector(int nr)
     /*  */
 597 {
 598         if (nr!=7) {
 599                 printk(" -- FDC reply errror");
 600                 reset = 1;
 601         } else
 602                 printk(": track %d, head %d, sector %d", reply_buffer[3],
 603                         reply_buffer[4], reply_buffer[5]);
 604 } /* tell_sector */
 605 
 606 
 607 /*
 608  * Ok, this interrupt is called after a DMA read/write has succeeded
 609  * or failed, so we check the results, and copy any buffers.
 610  * hhb: Added better error reporting.
 611  */
 612 static void rw_interrupt(void)
     /*  */
 613 {
 614         char * buffer_area;
 615         int nr;
 616         char bad;
 617 
 618         nr = result();
 619         /* check IC to find cause of interrupt */
 620         switch ((ST0 & ST0_INTR)>>6) {
 621                 case 1: /* error occured during command execution */
 622                         bad = 1;
 623                         if (ST1 & ST1_WP) {
 624                                 printk(DEVICE_NAME ": Drive %d is write protected\n", current_drive);
 625                                 request_done(0);
 626                                 bad = 0;
 627                         } else if (ST1 & ST1_OR) {
 628                                 if (ftd_msg[ST0 & ST0_DS])
 629                                         printk(DEVICE_NAME ": Over/Underrun - retrying\n");
 630                                 /* could continue from where we stopped, but ... */
 631                                 bad = 0;
 632                         } else if (CURRENT_ERRORS > min_report_error_cnt[ST0 & ST0_DS]) {
 633                                 printk(DEVICE_NAME " %d: ", ST0 & ST0_DS);
 634                                 if (ST0 & ST0_ECE) {
 635                                         printk("Recalibrate failed!");
 636                                 } else if (ST2 & ST2_CRC) {
 637                                         printk("data CRC error");
 638                                         tell_sector(nr);
 639                                 } else if (ST1 & ST1_CRC) {
 640                                         printk("CRC error");
 641                                         tell_sector(nr);
 642                                 } else if ((ST1 & (ST1_MAM|ST1_ND)) || (ST2 & ST2_MAM)) {
 643                                         if (!probing) {
 644                                                 printk("sector not found");
 645                                                 tell_sector(nr);
 646                                         } else
 647                                                 printk("probe failed...");
 648                                 } else if (ST2 & ST2_WC) {      /* seek error */
 649                                         printk("wrong cylinder");
 650                                 } else if (ST2 & ST2_BC) {      /* cylinder marked as bad */
 651                                         printk("bad cylinder");
 652                                 } else {
 653                                         printk("unknown error. ST[0..3] are: 0x%x 0x%x 0x%x 0x%x\n", ST0, ST1, ST2, ST3);
 654                                 }
 655                                 printk("\n");
 656 
 657                         }
 658                         if (bad)
 659                                 bad_flp_intr();
 660                         redo_fd_request();
 661                         return;
 662                 case 2: /* invalid command given */
 663                         printk(DEVICE_NAME ": Invalid FDC command given!\n");
 664                         request_done(0);
 665                         return;
 666                 case 3:
 667                         printk(DEVICE_NAME ": Abnormal termination caused by polling\n");
 668                         bad_flp_intr();
 669                         redo_fd_request();
 670                         return;
 671                 default: /* (0) Normal command termination */
 672                         break;
 673         }
 674 
 675         if (probing) {
 676                 int drive = MINOR(CURRENT->dev);
 677 
 678                 if (ftd_msg[drive])
 679                         printk("Auto-detected floppy type %s in fd%d\n",
 680                             floppy->name,drive);
 681                 current_type[drive] = floppy;
 682                 floppy_sizes[drive] = floppy->size >> 1;
 683                 probing = 0;
 684         }
 685         if (read_track) {
 686                 buffer_track = seek_track;
 687                 buffer_drive = current_drive;
 688                 buffer_area = floppy_track_buffer +
 689                         ((sector-1 + head*floppy->sect)<<9);
 690                 copy_buffer(buffer_area,CURRENT->buffer);
 691         } else if (command == FD_READ &&
 692                 (unsigned long)(CURRENT->buffer) >= LAST_DMA_ADDR)
 693                 copy_buffer(tmp_floppy_area,CURRENT->buffer);
 694         request_done(1);
 695         redo_fd_request();
 696 }
 697 
 698 /*
 699  * We try to read tracks, but if we get too many errors, we
 700  * go back to reading just one sector at a time.
 701  *
 702  * This means we should be able to read a sector even if there
 703  * are other bad sectors on this track.
 704  */
 705 inline void setup_rw_floppy(void)
     /*  */
 706 {
 707         setup_DMA();
 708         do_floppy = rw_interrupt;
 709         output_byte(command);
 710         if (command != FD_FORMAT) {
 711                 if (read_track) {
 712                         output_byte(current_drive);
 713                         output_byte(track);
 714                         output_byte(0);
 715                         output_byte(1);
 716                 } else {
 717                         output_byte(head<<2 | current_drive);
 718                         output_byte(track);
 719                         output_byte(head);
 720                         output_byte(sector);
 721                 }
 722                 output_byte(2);         /* sector size = 512 */
 723                 output_byte(floppy->sect);
 724                 output_byte(floppy->gap);
 725                 output_byte(0xFF);      /* sector size (0xff when n!=0 ?) */
 726         } else {
 727                 output_byte(head<<2 | current_drive);
 728                 output_byte(2);
 729                 output_byte(floppy->sect);
 730                 output_byte(floppy->fmt_gap);
 731                 output_byte(FD_FILL_BYTE);
 732         }
 733         if (reset)
 734                 redo_fd_request();
 735 }
 736 
 737 /*
 738  * This is the routine called after every seek (or recalibrate) interrupt
 739  * from the floppy controller. Note that the "unexpected interrupt" routine
 740  * also does a recalibrate, but doesn't come here.
 741  */
 742 static void seek_interrupt(void)
     /*  */
 743 {
 744 /* sense drive status */
 745         output_byte(FD_SENSEI);
 746         if (result() != 2 || (ST0 & 0xF8) != 0x20 || ST1 != seek_track) {
 747                 printk(DEVICE_NAME ": seek failed\n");
 748                 recalibrate = 1;
 749                 bad_flp_intr();
 750                 redo_fd_request();
 751                 return;
 752         }
 753         current_track = ST1;
 754         setup_rw_floppy();
 755 }
 756 
 757 
 758 /*
 759  * This routine is called when everything should be correctly set up
 760  * for the transfer (ie floppy motor is on and the correct floppy is
 761  * selected).
 762  */
 763 static void transfer(void)
     /*  */
 764 {
 765         read_track = (command == FD_READ) && (CURRENT_ERRORS < 4) &&
 766             (floppy->sect <= MAX_BUFFER_SECTORS);
 767 
 768         configure_fdc_mode();
 769 
 770         if (reset) {
 771                 redo_fd_request();
 772                 return;
 773         }
 774         if (!seek) {
 775                 setup_rw_floppy();
 776                 return;
 777         }
 778 
 779         do_floppy = seek_interrupt;
 780         output_byte(FD_SEEK);
 781         if (read_track)
 782                 output_byte(current_drive);
 783         else
 784                 output_byte((head<<2) | current_drive);
 785         output_byte(seek_track);
 786         if (reset)
 787                 redo_fd_request();
 788 }
 789 
 790 /*
 791  * Special case - used after a unexpected interrupt (or reset)
 792  */
 793 
 794 static void recalibrate_floppy(void);
 795 
 796 static void recal_interrupt(void)
     /*  */
 797 {
 798         output_byte(FD_SENSEI);
 799         current_track = NO_TRACK;
 800         if (result()!=2 || (ST0 & 0xE0) == 0x60)
 801                 reset = 1;
 802 /* Recalibrate until track 0 is reached. Might help on some errors. */
 803         if ((ST0 & 0x10) == 0x10)
 804                 recalibrate_floppy();   /* FIXME: should limit nr of recalibrates */
 805         else
 806                 redo_fd_request();
 807 }
 808 
 809 static void unexpected_floppy_interrupt(void)
     /*  */
 810 {
 811         current_track = NO_TRACK;
 812         output_byte(FD_SENSEI);
 813         printk(DEVICE_NAME ": unexpected interrupt\n");
 814         if (result()!=2 || (ST0 & 0xE0) == 0x60)
 815                 reset = 1;
 816         else
 817                 recalibrate = 1;
 818 }
 819 
 820 static void recalibrate_floppy(void)
     /*  */
 821 {
 822         recalibrate = 0;
 823         current_track = 0;
 824         do_floppy = recal_interrupt;
 825         output_byte(FD_RECALIBRATE);
 826         output_byte(head<<2 | current_drive);
 827         if (reset)
 828                 redo_fd_request();
 829 }
 830 
 831 /*
 832  * Must do 4 FD_SENSEIs after reset because of ``drive polling''.
 833  */
 834 static void reset_interrupt(void)
     /*  */
 835 {
 836         short i;
 837 
 838         for (i=0; i<4; i++) {
 839                 output_byte(FD_SENSEI);
 840                 (void) result();
 841         }
 842         output_byte(FD_SPECIFY);
 843         output_byte(cur_spec1);         /* hut etc */
 844         output_byte(6);                 /* Head load time =6ms, DMA */
 845         configure_fdc_mode();           /* reprogram fdc */
 846         if (initial_reset_flag) {
 847                 initial_reset_flag = 0;
 848                 recalibrate = 1;
 849                 reset = 0;
 850                 return;
 851         }
 852         if (!recover)
 853                 redo_fd_request();
 854         else {
 855                 recalibrate_floppy();
 856                 recover = 0;
 857         }
 858 }
 859 
 860 /*
 861  * reset is done by pulling bit 2 of DOR low for a while.
 862  */
 863 static void reset_floppy(void)
     /*  */
 864 {
 865         int i;
 866 
 867         do_floppy = reset_interrupt;
 868         reset = 0;
 869         current_track = NO_TRACK;
 870         cur_spec1 = -1;
 871         cur_rate = -1;
 872         recalibrate = 1;
 873         need_configure = 1;
 874         if (!initial_reset_flag)
 875                 printk("Reset-floppy called\n");
 876         cli();
 877         outb_p(current_DOR & ~0x04, FD_DOR);
 878         for (i=0 ; i<1000 ; i++)
 879                 __asm__("nop");
 880         outb(current_DOR, FD_DOR);
 881         sti();
 882 }
 883 
 884 static void floppy_shutdown(void)
     /*  */
 885 {
 886         cli();
 887         do_floppy = NULL;
 888         request_done(0);
 889         recover = 1;
 890         reset_floppy();
 891         sti();
 892         redo_fd_request();
 893 }
 894 
 895 static void shake_done(void)
     /*  */
 896 {
 897         current_track = NO_TRACK;
 898         if (inb(FD_DIR) & 0x80)
 899                 request_done(0);
 900         redo_fd_request();
 901 }
 902 
 903 static int retry_recal(void (*proc)(void))
     /*  */
 904 {
 905         output_byte(FD_SENSEI);
 906         if (result() == 2 && (ST0 & 0x10) != 0x10) return 0;
 907         do_floppy = proc;
 908         output_byte(FD_RECALIBRATE);
 909         output_byte(head<<2 | current_drive);
 910         return 1;
 911 }
 912 
 913 static void shake_zero(void)
     /*  */
 914 {
 915         if (!retry_recal(shake_zero)) shake_done();
 916 }
 917 
 918 static void shake_one(void)
     /*  */
 919 {
 920         if (retry_recal(shake_one)) return;
 921         do_floppy = shake_done;
 922         output_byte(FD_SEEK);
 923         output_byte(head << 2 | current_drive);
 924         output_byte(1);
 925 }
 926 
 927 static void floppy_ready(void)
     /*  */
 928 {
 929         if (inb(FD_DIR) & 0x80) {
 930                 changed_floppies |= 1<<current_drive;
 931                 buffer_track = -1;
 932                 if (keep_data[current_drive]) {
 933                         if (keep_data[current_drive] > 0)
 934                                 keep_data[current_drive]--;
 935                 } else {
 936                         if (ftd_msg[current_drive] && current_type[current_drive] != NULL)
 937                                 printk("Disk type is undefined after disk "
 938                                     "change in fd%d\n",current_drive);
 939                         current_type[current_drive] = NULL;
 940                         floppy_sizes[current_drive] = MAX_DISK_SIZE;
 941                 }
 942 /* Forcing the drive to seek makes the "media changed" condition go away.
 943  * There should be a cleaner solution for that ...
 944  */
 945                 if (!reset && !recalibrate) {
 946                         if (current_track && current_track != NO_TRACK)
 947                                 do_floppy = shake_zero;
 948                         else
 949                                 do_floppy = shake_one;
 950                         output_byte(FD_RECALIBRATE);
 951                         output_byte(head<<2 | current_drive);
 952                         return;
 953                 }
 954         }
 955         if (reset) {
 956                 reset_floppy();
 957                 return;
 958         }
 959         if (recalibrate) {
 960                 recalibrate_floppy();
 961                 return;
 962         }
 963         transfer();
 964 }
 965 
 966 static void setup_format_params(void)
     /*  */
 967 {
 968     unsigned char *here = (unsigned char *) tmp_floppy_area;
 969     int count,head_shift,track_shift,total_shift;
 970 
 971     /* allow for about 30ms for data transport per track */
 972     head_shift  = floppy->sect / 6;
 973     /* a ``cylinder'' is two tracks plus a little stepping time */
 974     track_shift = 2 * head_shift + 1; 
 975     /* count backwards */
 976     total_shift = floppy->sect - 
 977         ((track_shift * track + head_shift * head) % floppy->sect);
 978 
 979     /* XXX: should do a check to see this fits in tmp_floppy_area!! */
 980     for (count = 0; count < floppy->sect; count++) {
 981         *here++ = track;
 982         *here++ = head;
 983         *here++ = 1 + (( count + total_shift ) % floppy->sect);
 984         *here++ = 2; /* 512 bytes */
 985     }
 986 }
 987 
 988 static void redo_fd_request(void)
     /*  */
 989 {
 990         unsigned int block;
 991         char * buffer_area;
 992         int device;
 993 
 994         if (CURRENT && CURRENT->dev < 0) return;
 995 
 996 repeat:
 997         if (format_status == FORMAT_WAIT)
 998                 format_status = FORMAT_BUSY;
 999         if (format_status != FORMAT_BUSY) {
1000                 if (!CURRENT) {
1001                         if (!fdc_busy)
1002                                 printk("FDC access conflict!");
1003                         fdc_busy = 0;
1004                         wake_up(&fdc_wait);
1005                         CLEAR_INTR;
1006                         return;
1007                 }
1008                 if (MAJOR(CURRENT->dev) != MAJOR_NR)
1009                         panic(DEVICE_NAME ": request list destroyed"); \
1010                 if (CURRENT->bh) {
1011                         if (!CURRENT->bh->b_lock)
1012                                 panic(DEVICE_NAME ": block not locked");
1013                 }
1014         }
1015         seek = 0;
1016         probing = 0;
1017         device = MINOR(CURRENT_DEVICE);
1018         if (device > 3)
1019                 floppy = (device >> 2) + floppy_type;
1020         else { /* Auto-detection */
1021                 floppy = current_type[device & 3];
1022                 if (!floppy) {
1023                         probing = 1;
1024                         floppy = base_type[device & 3];
1025                         if (!floppy) {
1026                                 request_done(0);
1027                                 goto repeat;
1028                         }
1029                         if (CURRENT_ERRORS & 1)
1030                                 floppy++;
1031                 }
1032         }
1033         if (format_status != FORMAT_BUSY) {
1034                 if (current_drive != CURRENT_DEV) {
1035                         current_track = NO_TRACK;
1036                         current_drive = CURRENT_DEV;
1037                 }
1038                 block = CURRENT->sector;
1039                 if (block+2 > floppy->size) {
1040                         request_done(0);
1041                         goto repeat;
1042                 }
1043                 sector = block % floppy->sect;
1044                 block /= floppy->sect;
1045                 head = block % floppy->head;
1046                 track = block / floppy->head;
1047                 seek_track = track << floppy->stretch;
1048                 if (CURRENT->cmd == READ)
1049                         command = FD_READ;
1050                 else if (CURRENT->cmd == WRITE)
1051                         command = FD_WRITE;
1052                 else {
1053                         printk("do_fd_request: unknown command\n");
1054                         request_done(0);
1055                         goto repeat;
1056                 }
1057         } else {
1058                 if (current_drive != (format_req.device & 3))
1059                         current_track = NO_TRACK;
1060                 current_drive = format_req.device & 3;
1061                 if (((unsigned) format_req.track) >= floppy->track ||
1062                     (format_req.head & 0xfffe) || probing) {
1063                         request_done(0);
1064                         goto repeat;
1065                 }
1066                 head = format_req.head;
1067                 track = format_req.track;
1068                 seek_track = track << floppy->stretch;
1069                 if (seek_track == buffer_track) buffer_track = -1;
1070                 command = FD_FORMAT;
1071                 setup_format_params();
1072         }
1073         timer_table[FLOPPY_TIMER].expires = jiffies+10*HZ;
1074         timer_active |= 1 << FLOPPY_TIMER;
1075         if ((seek_track == buffer_track) &&
1076          (current_drive == buffer_drive)) {
1077                 buffer_area = floppy_track_buffer +
1078                         ((sector + head*floppy->sect)<<9);
1079                 if (command == FD_READ) {
1080                         copy_buffer(buffer_area,CURRENT->buffer);
1081                         request_done(1);
1082                         goto repeat;
1083                 } else if (command == FD_WRITE)
1084                         copy_buffer(CURRENT->buffer,buffer_area);
1085         }
1086         if (seek_track != current_track)
1087                 seek = 1;
1088         sector++;
1089         del_timer(motor_off_timer + current_drive);
1090         floppy_on(current_drive);
1091 }
1092 
1093 void do_fd_request(void)
     /*  */
1094 {
1095         cli();
1096         while (fdc_busy) sleep_on(&fdc_wait);
1097         fdc_busy = 1;
1098         sti();
1099         redo_fd_request();
1100 }
1101 
1102 static int fd_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
     /*  */
1103     unsigned long param)
1104 {
1105         int i,drive,cnt,okay;
1106         struct floppy_struct *this_floppy;
1107 
1108         switch (cmd) {
1109                 RO_IOCTLS(inode->i_rdev,param);
1110         }
1111         drive = MINOR(inode->i_rdev);
1112         switch (cmd) {
1113                 case FDFMTBEG:
1114                         if (!suser())
1115                                 return -EPERM;
1116                         return 0;
1117                 case FDFMTEND:
1118                         if (!suser())
1119                                 return -EPERM;
1120                         cli();
1121                         fake_change |= 1 << (drive & 3);
1122                         sti();
1123                         drive &= 3;
1124                         cmd = FDCLRPRM;
1125                         break;
1126                 case FDGETPRM:
1127                         if (drive > 3) this_floppy = &floppy_type[drive >> 2];
1128                         else if ((this_floppy = current_type[drive & 3]) == NULL)
1129                                     return -ENODEV;
1130                         i = verify_area(VERIFY_WRITE,(void *) param,sizeof(struct floppy_struct));
1131                         if (i)
1132                                 return i;
1133                         for (cnt = 0; cnt < sizeof(struct floppy_struct); cnt++)
1134                                 put_fs_byte(((char *) this_floppy)[cnt],
1135                                     (char *) param+cnt);
1136                         return 0;
1137                 case FDFMTTRK:
1138                         if (!suser())
1139                                 return -EPERM;
1140                         cli();
1141                         while (format_status != FORMAT_NONE)
1142                                 sleep_on(&format_done);
1143                         for (cnt = 0; cnt < sizeof(struct format_descr); cnt++)
1144                                 ((char *) &format_req)[cnt] = get_fs_byte(
1145                                     (char *) param+cnt);
1146                         format_req.device = drive;
1147                         format_status = FORMAT_WAIT;
1148                         format_errors = 0;
1149                         while (format_status != FORMAT_OKAY && format_status !=
1150                             FORMAT_ERROR) {
1151                                 if (fdc_busy) sleep_on(&fdc_wait);
1152                                 else {
1153                                         fdc_busy = 1;
1154                                         redo_fd_request();
1155                                 }
1156                         }
1157                         while (format_status != FORMAT_OKAY && format_status !=
1158                             FORMAT_ERROR)
1159                                 sleep_on(&format_done);
1160                         sti();
1161                         okay = format_status == FORMAT_OKAY;
1162                         format_status = FORMAT_NONE;
1163                         wake_up(&format_done);
1164                         return okay ? 0 : -EIO;
1165                 case FDFLUSH:
1166                         if (!permission(inode, 2))
1167                                 return -EPERM;
1168                         cli();
1169                         fake_change |= 1 << (drive & 3);
1170                         sti();
1171                         check_disk_change(inode->i_rdev);
1172                         return 0;
1173         }
1174         if (!suser())
1175                 return -EPERM;
1176         if (drive < 0 || drive > 3)
1177                 return -EINVAL;
1178         switch (cmd) {
1179                 case FDCLRPRM:
1180                         current_type[drive] = NULL;
1181                         floppy_sizes[drive] = MAX_DISK_SIZE;
1182                         keep_data[drive] = 0;
1183                         break;
1184                 case FDSETPRM:
1185                 case FDDEFPRM:
1186                         memcpy_fromfs(user_params+drive,
1187                                 (void *) param,
1188                                 sizeof(struct floppy_struct));
1189                         current_type[drive] = &user_params[drive];
1190                         floppy_sizes[drive] = user_params[drive].size >> 1;
1191                         if (cmd == FDDEFPRM)
1192                                 keep_data[drive] = -1;
1193                         else {
1194                                 cli();
1195                                 while (fdc_busy) sleep_on(&fdc_wait);
1196                                 fdc_busy = 1;
1197                                 sti();
1198                                 outb_p((current_DOR & 0xfc) | drive |
1199                                     (0x10 << drive),FD_DOR);
1200                                 for (cnt = 0; cnt < 1000; cnt++) __asm__("nop");
1201                                 if (inb(FD_DIR) & 0x80)
1202                                         keep_data[drive] = 1;
1203                                 else
1204                                         keep_data[drive] = 0;
1205                                 outb_p(current_DOR,FD_DOR);
1206                                 fdc_busy = 0;
1207                                 wake_up(&fdc_wait);
1208                         }
1209                         break;
1210                 case FDMSGON:
1211                         ftd_msg[drive] = 1;
1212                         break;
1213                 case FDMSGOFF:
1214                         ftd_msg[drive] = 0;
1215                         break;
1216                 case FDSETEMSGTRESH:
1217                         min_report_error_cnt[drive] = (unsigned short) (param & 0x0f);
1218                         break;
1219                 default:
1220                         return -EINVAL;
1221         }
1222         return 0;
1223 }
1224 
1225 #define CMOS_READ(addr) ({ \
1226 outb_p(addr,0x70); \
1227 inb_p(0x71); \
1228 })
1229 
1230 static struct floppy_struct *find_base(int drive,int code)
     /*  */
1231 {
1232         struct floppy_struct *base;
1233 
1234         if (code > 0 && code < 5) {
1235                 base = &floppy_types[(code-1)*2];
1236                 printk("fd%d is %s",drive,base->name);
1237                 return base;
1238         }
1239         printk("fd%d is unknown type %d",drive,code);
1240         return NULL;
1241 }
1242 
1243 static void config_types(void)
     /*  */
1244 {
1245         printk("Floppy drive(s): ");
1246         base_type[0] = find_base(0,(CMOS_READ(0x10) >> 4) & 15);
1247         if (((CMOS_READ(0x14) >> 6) & 1) == 0)
1248                 base_type[1] = NULL;
1249         else {
1250                 printk(", ");
1251                 base_type[1] = find_base(1,CMOS_READ(0x10) & 15);
1252         }
1253         base_type[2] = base_type[3] = NULL;
1254         printk("\n");
1255 }
1256 
1257 /*
1258  * floppy_open check for aliasing (/dev/fd0 can be the same as
1259  * /dev/PS0 etc), and disallows simultaneous access to the same
1260  * drive with different device numbers.
1261  */
1262 static int floppy_open(struct inode * inode, struct file * filp)
     /*  */
1263 {
1264         int drive;
1265         int old_dev;
1266 
1267         drive = inode->i_rdev & 3;
1268         old_dev = fd_device[drive];
1269         if (fd_ref[drive])
1270                 if (old_dev != inode->i_rdev)
1271                         return -EBUSY;
1272         fd_ref[drive]++;
1273         fd_device[drive] = inode->i_rdev;
1274         buffer_drive = buffer_track = -1;
1275         if (old_dev && old_dev != inode->i_rdev)
1276                 invalidate_buffers(old_dev);
1277         if (filp && filp->f_mode)
1278                 check_disk_change(inode->i_rdev);
1279         return 0;
1280 }
1281 
1282 static void floppy_release(struct inode * inode, struct file * filp)
     /*  */
1283 {
1284         sync_dev(inode->i_rdev);
1285         if (!fd_ref[inode->i_rdev & 3]--) {
1286                 printk("floppy_release with fd_ref == 0");
1287                 fd_ref[inode->i_rdev & 3] = 0;
1288         }
1289 }
1290 
1291 static struct file_operations floppy_fops = {
1292         NULL,                   /* lseek - default */
1293         block_read,             /* read - general block-dev read */
1294         block_write,            /* write - general block-dev write */
1295         NULL,                   /* readdir - bad */
1296         NULL,                   /* select */
1297         fd_ioctl,               /* ioctl */
1298         NULL,                   /* mmap */
1299         floppy_open,            /* open */
1300         floppy_release,         /* release */
1301         block_fsync             /* fsync */
1302 };
1303 
1304 
1305 /*
1306  * The version command is not supposed to generate an interrupt, but
1307  * my FDC does, except when booting in SVGA screen mode.
1308  * When it does generate an interrupt, it doesn't return any status bytes.
1309  * It appears to have something to do with the version command...
1310  *
1311  * This should never be called, because of the reset after the version check.
1312  */
1313 static void ignore_interrupt(void)
     /*  */
1314 {
1315         printk(DEVICE_NAME ": weird interrupt ignored (%d)\n", result());
1316         reset = 1;
1317         CLEAR_INTR;     /* ignore only once */
1318 }
1319 
1320 
1321 static void floppy_interrupt(int unused)
     /*  */
1322 {
1323         void (*handler)(void) = DEVICE_INTR;
1324 
1325         DEVICE_INTR = NULL;
1326         if (!handler)
1327                 handler = unexpected_floppy_interrupt;
1328         handler();
1329 }
1330 
1331 /*
1332  * This is the floppy IRQ description. The SA_INTERRUPT in sa_flags
1333  * means we run the IRQ-handler with interrupts disabled.
1334  */
1335 static struct sigaction floppy_sigaction = {
1336         floppy_interrupt,
1337         0,
1338         SA_INTERRUPT,
1339         NULL
1340 };
1341 
1342 void floppy_init(void)
     /*  */
1343 {
1344         outb(current_DOR,FD_DOR);
1345         if (register_blkdev(MAJOR_NR,"fd",&floppy_fops)) {
1346                 printk("Unable to get major %d for floppy\n",MAJOR_NR);
1347                 return;
1348         }
1349         blk_size[MAJOR_NR] = floppy_sizes;
1350         blk_dev[MAJOR_NR].request_fn = DEVICE_REQUEST;
1351         timer_table[FLOPPY_TIMER].fn = floppy_shutdown;
1352         timer_active &= ~(1 << FLOPPY_TIMER);
1353         config_types();
1354         if (irqaction(FLOPPY_IRQ,&floppy_sigaction))
1355                 printk("Unable to grab IRQ%d for the floppy driver\n", FLOPPY_IRQ);
1356         if (request_dma(FLOPPY_DMA))
1357                 printk("Unable to grab DMA%d for the floppy driver\n", FLOPPY_DMA);
1358         /* Try to determine the floppy controller type */
1359         DEVICE_INTR = ignore_interrupt; /* don't ask ... */
1360         output_byte(FD_VERSION);        /* get FDC version code */
1361         if (result() != 1) {
1362                 printk(DEVICE_NAME ": FDC failed to return version byte\n");
1363                 fdc_version = FDC_TYPE_STD;
1364         } else
1365                 fdc_version = reply_buffer[0];
1366         if (fdc_version != FDC_TYPE_STD) 
1367                 printk(DEVICE_NAME ": FDC version 0x%x\n", fdc_version);
1368 #ifndef FDC_FIFO_UNTESTED
1369         fdc_version = FDC_TYPE_STD;     /* force std fdc type; can't test other. */
1370 #endif
1371 
1372         /* Not all FDCs seem to be able to handle the version command
1373          * properly, so force a reset for the standard FDC clones,
1374          * to avoid interrupt garbage.
1375          */
1376 
1377         if (fdc_version == FDC_TYPE_STD) {
1378                 initial_reset_flag = 1;
1379                 reset_floppy();
1380         }
1381 }
/* */
root/kernel/blk_drv/floppy.c

DEFINITIONS
