xref: /openbmc/linux/drivers/block/amiflop.c (revision 82e6fdd6)
1 /*
2  *  linux/amiga/amiflop.c
3  *
4  *  Copyright (C) 1993  Greg Harp
5  *  Portions of this driver are based on code contributed by Brad Pepers
6  *
7  *  revised 28.5.95 by Joerg Dorchain
8  *  - now no bugs(?) any more for both HD & DD
9  *  - added support for 40 Track 5.25" drives, 80-track hopefully behaves
10  *    like 3.5" dd (no way to test - are there any 5.25" drives out there
11  *    that work on an A4000?)
12  *  - wrote formatting routine (maybe dirty, but works)
13  *
14  *  june/july 1995 added ms-dos support by Joerg Dorchain
15  *  (portions based on messydos.device and various contributors)
16  *  - currently only 9 and 18 sector disks
17  *
18  *  - fixed a bug with the internal trackbuffer when using multiple
19  *    disks the same time
20  *  - made formatting a bit safer
21  *  - added command line and machine based default for "silent" df0
22  *
23  *  december 1995 adapted for 1.2.13pl4 by Joerg Dorchain
24  *  - works but I think it's inefficient. (look in redo_fd_request)
25  *    But the changes were very efficient. (only three and a half lines)
26  *
27  *  january 1996 added special ioctl for tracking down read/write problems
28  *  - usage ioctl(d, RAW_TRACK, ptr); the raw track buffer (MFM-encoded data
29  *    is copied to area. (area should be large enough since no checking is
30  *    done - 30K is currently sufficient). return the actual size of the
31  *    trackbuffer
32  *  - replaced udelays() by a timer (CIAA timer B) for the waits
33  *    needed for the disk mechanic.
34  *
35  *  february 1996 fixed error recovery and multiple disk access
36  *  - both got broken the first time I tampered with the driver :-(
37  *  - still not safe, but better than before
38  *
39  *  revised Marts 3rd, 1996 by Jes Sorensen for use in the 1.3.28 kernel.
40  *  - Minor changes to accept the kdev_t.
41  *  - Replaced some more udelays with ms_delays. Udelay is just a loop,
42  *    and so the delay will be different depending on the given
43  *    processor :-(
44  *  - The driver could use a major cleanup because of the new
45  *    major/minor handling that came with kdev_t. It seems to work for
46  *    the time being, but I can't guarantee that it will stay like
47  *    that when we start using 16 (24?) bit minors.
48  *
49  * restructured jan 1997 by Joerg Dorchain
50  * - Fixed Bug accessing multiple disks
51  * - some code cleanup
52  * - added trackbuffer for each drive to speed things up
53  * - fixed some race conditions (who finds the next may send it to me ;-)
54  */
55 
56 #include <linux/module.h>
57 #include <linux/slab.h>
58 
59 #include <linux/fd.h>
60 #include <linux/hdreg.h>
61 #include <linux/delay.h>
62 #include <linux/init.h>
63 #include <linux/mutex.h>
64 #include <linux/amifdreg.h>
65 #include <linux/amifd.h>
66 #include <linux/fs.h>
67 #include <linux/blkdev.h>
68 #include <linux/elevator.h>
69 #include <linux/interrupt.h>
70 #include <linux/platform_device.h>
71 
72 #include <asm/setup.h>
73 #include <linux/uaccess.h>
74 #include <asm/amigahw.h>
75 #include <asm/amigaints.h>
76 #include <asm/irq.h>
77 
78 #undef DEBUG /* print _LOTS_ of infos */
79 
80 #define RAW_IOCTL
81 #ifdef RAW_IOCTL
82 #define IOCTL_RAW_TRACK 0x5254524B  /* 'RTRK' */
83 #endif
84 
85 /*
86  *  Defines
87  */
88 
89 /*
90  *  Error codes
91  */
92 #define FD_OK		0	/* operation succeeded */
93 #define FD_ERROR	-1	/* general error (seek, read, write, etc) */
94 #define FD_NOUNIT	1	/* unit does not exist */
95 #define FD_UNITBUSY	2	/* unit already active */
96 #define FD_NOTACTIVE	3	/* unit is not active */
97 #define FD_NOTREADY	4	/* unit is not ready (motor not on/no disk) */
98 
99 #define MFM_NOSYNC	1
100 #define MFM_HEADER	2
101 #define MFM_DATA	3
102 #define MFM_TRACK	4
103 
104 /*
105  *  Floppy ID values
106  */
107 #define FD_NODRIVE	0x00000000  /* response when no unit is present */
108 #define FD_DD_3 	0xffffffff  /* double-density 3.5" (880K) drive */
109 #define FD_HD_3 	0x55555555  /* high-density 3.5" (1760K) drive */
110 #define FD_DD_5 	0xaaaaaaaa  /* double-density 5.25" (440K) drive */
111 
112 static DEFINE_MUTEX(amiflop_mutex);
113 static unsigned long int fd_def_df0 = FD_DD_3;     /* default for df0 if it doesn't identify */
114 
115 module_param(fd_def_df0, ulong, 0);
116 MODULE_LICENSE("GPL");
117 
118 /*
119  *  Macros
120  */
121 #define MOTOR_ON	(ciab.prb &= ~DSKMOTOR)
122 #define MOTOR_OFF	(ciab.prb |= DSKMOTOR)
123 #define SELECT(mask)    (ciab.prb &= ~mask)
124 #define DESELECT(mask)  (ciab.prb |= mask)
125 #define SELMASK(drive)  (1 << (3 + (drive & 3)))
126 
127 static struct fd_drive_type drive_types[] = {
128 /*  code	name	   tr he   rdsz   wrsz sm pc1 pc2 sd  st st*/
129 /*  warning: times are now in milliseconds (ms)                    */
130 { FD_DD_3,	"DD 3.5",  80, 2, 14716, 13630, 1, 80,161, 3, 18, 1},
131 { FD_HD_3,	"HD 3.5",  80, 2, 28344, 27258, 2, 80,161, 3, 18, 1},
132 { FD_DD_5,	"DD 5.25", 40, 2, 14716, 13630, 1, 40, 81, 6, 30, 2},
133 { FD_NODRIVE, "No Drive", 0, 0,     0,     0, 0,  0,  0,  0,  0, 0}
134 };
135 static int num_dr_types = ARRAY_SIZE(drive_types);
136 
137 static int amiga_read(int), dos_read(int);
138 static void amiga_write(int), dos_write(int);
139 static struct fd_data_type data_types[] = {
140 	{ "Amiga", 11 , amiga_read, amiga_write},
141 	{ "MS-Dos", 9, dos_read, dos_write}
142 };
143 
144 /* current info on each unit */
145 static struct amiga_floppy_struct unit[FD_MAX_UNITS];
146 
147 static struct timer_list flush_track_timer[FD_MAX_UNITS];
148 static struct timer_list post_write_timer;
149 static unsigned long post_write_timer_drive;
150 static struct timer_list motor_on_timer;
151 static struct timer_list motor_off_timer[FD_MAX_UNITS];
152 static int on_attempts;
153 
154 /* Synchronization of FDC access */
155 /* request loop (trackbuffer) */
156 static volatile int fdc_busy = -1;
157 static volatile int fdc_nested;
158 static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
159 
160 static DECLARE_COMPLETION(motor_on_completion);
161 
162 static volatile int selected = -1;	/* currently selected drive */
163 
164 static int writepending;
165 static int writefromint;
166 static char *raw_buf;
167 static int fdc_queue;
168 
169 static DEFINE_SPINLOCK(amiflop_lock);
170 
171 #define RAW_BUF_SIZE 30000  /* size of raw disk data */
172 
173 /*
174  * These are global variables, as that's the easiest way to give
175  * information to interrupts. They are the data used for the current
176  * request.
177  */
178 static volatile char block_flag;
179 static DECLARE_WAIT_QUEUE_HEAD(wait_fd_block);
180 
181 /* MS-Dos MFM Coding tables (should go quick and easy) */
182 static unsigned char mfmencode[16]={
183 	0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15,
184 	0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55
185 };
186 static unsigned char mfmdecode[128];
187 
188 /* floppy internal millisecond timer stuff */
189 static DECLARE_COMPLETION(ms_wait_completion);
190 #define MS_TICKS ((amiga_eclock+50)/1000)
191 
192 /*
193  * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
194  * max X times - some types of errors increase the errorcount by 2 or
195  * even 3, so we might actually retry only X/2 times before giving up.
196  */
197 #define MAX_ERRORS 12
198 
199 #define custom amiga_custom
200 
201 /* Prevent "aliased" accesses. */
202 static int fd_ref[4] = { 0,0,0,0 };
203 static int fd_device[4] = { 0, 0, 0, 0 };
204 
205 /*
206  * Here come the actual hardware access and helper functions.
207  * They are not reentrant and single threaded because all drives
208  * share the same hardware and the same trackbuffer.
209  */
210 
211 /* Milliseconds timer */
212 
213 static irqreturn_t ms_isr(int irq, void *dummy)
214 {
215 	complete(&ms_wait_completion);
216 	return IRQ_HANDLED;
217 }
218 
219 /* all waits are queued up
220    A more generic routine would do a schedule a la timer.device */
221 static void ms_delay(int ms)
222 {
223 	int ticks;
224 	static DEFINE_MUTEX(mutex);
225 
226 	if (ms > 0) {
227 		mutex_lock(&mutex);
228 		ticks = MS_TICKS*ms-1;
229 		ciaa.tblo=ticks%256;
230 		ciaa.tbhi=ticks/256;
231 		ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
232 		wait_for_completion(&ms_wait_completion);
233 		mutex_unlock(&mutex);
234 	}
235 }
236 
237 /* Hardware semaphore */
238 
239 /* returns true when we would get the semaphore */
240 static inline int try_fdc(int drive)
241 {
242 	drive &= 3;
243 	return ((fdc_busy < 0) || (fdc_busy == drive));
244 }
245 
246 static void get_fdc(int drive)
247 {
248 	unsigned long flags;
249 
250 	drive &= 3;
251 #ifdef DEBUG
252 	printk("get_fdc: drive %d  fdc_busy %d  fdc_nested %d\n",drive,fdc_busy,fdc_nested);
253 #endif
254 	local_irq_save(flags);
255 	wait_event(fdc_wait, try_fdc(drive));
256 	fdc_busy = drive;
257 	fdc_nested++;
258 	local_irq_restore(flags);
259 }
260 
261 static inline void rel_fdc(void)
262 {
263 #ifdef DEBUG
264 	if (fdc_nested == 0)
265 		printk("fd: unmatched rel_fdc\n");
266 	printk("rel_fdc: fdc_busy %d fdc_nested %d\n",fdc_busy,fdc_nested);
267 #endif
268 	fdc_nested--;
269 	if (fdc_nested == 0) {
270 		fdc_busy = -1;
271 		wake_up(&fdc_wait);
272 	}
273 }
274 
275 static void fd_select (int drive)
276 {
277 	unsigned char prb = ~0;
278 
279 	drive&=3;
280 #ifdef DEBUG
281 	printk("selecting %d\n",drive);
282 #endif
283 	if (drive == selected)
284 		return;
285 	get_fdc(drive);
286 	selected = drive;
287 
288 	if (unit[drive].track % 2 != 0)
289 		prb &= ~DSKSIDE;
290 	if (unit[drive].motor == 1)
291 		prb &= ~DSKMOTOR;
292 	ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
293 	ciab.prb = prb;
294 	prb &= ~SELMASK(drive);
295 	ciab.prb = prb;
296 	rel_fdc();
297 }
298 
299 static void fd_deselect (int drive)
300 {
301 	unsigned char prb;
302 	unsigned long flags;
303 
304 	drive&=3;
305 #ifdef DEBUG
306 	printk("deselecting %d\n",drive);
307 #endif
308 	if (drive != selected) {
309 		printk(KERN_WARNING "Deselecting drive %d while %d was selected!\n",drive,selected);
310 		return;
311 	}
312 
313 	get_fdc(drive);
314 	local_irq_save(flags);
315 
316 	selected = -1;
317 
318 	prb = ciab.prb;
319 	prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
320 	ciab.prb = prb;
321 
322 	local_irq_restore (flags);
323 	rel_fdc();
324 
325 }
326 
327 static void motor_on_callback(struct timer_list *unused)
328 {
329 	if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
330 		complete_all(&motor_on_completion);
331 	} else {
332 		motor_on_timer.expires = jiffies + HZ/10;
333 		add_timer(&motor_on_timer);
334 	}
335 }
336 
337 static int fd_motor_on(int nr)
338 {
339 	nr &= 3;
340 
341 	del_timer(motor_off_timer + nr);
342 
343 	if (!unit[nr].motor) {
344 		unit[nr].motor = 1;
345 		fd_select(nr);
346 
347 		reinit_completion(&motor_on_completion);
348 		mod_timer(&motor_on_timer, jiffies + HZ/2);
349 
350 		on_attempts = 10;
351 		wait_for_completion(&motor_on_completion);
352 		fd_deselect(nr);
353 	}
354 
355 	if (on_attempts == 0) {
356 		on_attempts = -1;
357 #if 0
358 		printk (KERN_ERR "motor_on failed, turning motor off\n");
359 		fd_motor_off (motor_off_timer + nr);
360 		return 0;
361 #else
362 		printk (KERN_WARNING "DSKRDY not set after 1.5 seconds - assuming drive is spinning notwithstanding\n");
363 #endif
364 	}
365 
366 	return 1;
367 }
368 
369 static void fd_motor_off(struct timer_list *timer)
370 {
371 	unsigned long drive = ((unsigned long)timer -
372 			       (unsigned long)&motor_off_timer[0]) /
373 					sizeof(motor_off_timer[0]);
374 
375 	drive&=3;
376 	if (!try_fdc(drive)) {
377 		/* We would be blocked in an interrupt, so try again later */
378 		timer->expires = jiffies + 1;
379 		add_timer(timer);
380 		return;
381 	}
382 	unit[drive].motor = 0;
383 	fd_select(drive);
384 	udelay (1);
385 	fd_deselect(drive);
386 }
387 
388 static void floppy_off (unsigned int nr)
389 {
390 	int drive;
391 
392 	drive = nr & 3;
393 	mod_timer(motor_off_timer + drive, jiffies + 3*HZ);
394 }
395 
396 static int fd_calibrate(int drive)
397 {
398 	unsigned char prb;
399 	int n;
400 
401 	drive &= 3;
402 	get_fdc(drive);
403 	if (!fd_motor_on (drive))
404 		return 0;
405 	fd_select (drive);
406 	prb = ciab.prb;
407 	prb |= DSKSIDE;
408 	prb &= ~DSKDIREC;
409 	ciab.prb = prb;
410 	for (n = unit[drive].type->tracks/2; n != 0; --n) {
411 		if (ciaa.pra & DSKTRACK0)
412 			break;
413 		prb &= ~DSKSTEP;
414 		ciab.prb = prb;
415 		prb |= DSKSTEP;
416 		udelay (2);
417 		ciab.prb = prb;
418 		ms_delay(unit[drive].type->step_delay);
419 	}
420 	ms_delay (unit[drive].type->settle_time);
421 	prb |= DSKDIREC;
422 	n = unit[drive].type->tracks + 20;
423 	for (;;) {
424 		prb &= ~DSKSTEP;
425 		ciab.prb = prb;
426 		prb |= DSKSTEP;
427 		udelay (2);
428 		ciab.prb = prb;
429 		ms_delay(unit[drive].type->step_delay + 1);
430 		if ((ciaa.pra & DSKTRACK0) == 0)
431 			break;
432 		if (--n == 0) {
433 			printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);
434 			fd_motor_off (motor_off_timer + drive);
435 			unit[drive].track = -1;
436 			rel_fdc();
437 			return 0;
438 		}
439 	}
440 	unit[drive].track = 0;
441 	ms_delay(unit[drive].type->settle_time);
442 
443 	rel_fdc();
444 	fd_deselect(drive);
445 	return 1;
446 }
447 
448 static int fd_seek(int drive, int track)
449 {
450 	unsigned char prb;
451 	int cnt;
452 
453 #ifdef DEBUG
454 	printk("seeking drive %d to track %d\n",drive,track);
455 #endif
456 	drive &= 3;
457 	get_fdc(drive);
458 	if (unit[drive].track == track) {
459 		rel_fdc();
460 		return 1;
461 	}
462 	if (!fd_motor_on(drive)) {
463 		rel_fdc();
464 		return 0;
465 	}
466 	if (unit[drive].track < 0 && !fd_calibrate(drive)) {
467 		rel_fdc();
468 		return 0;
469 	}
470 
471 	fd_select (drive);
472 	cnt = unit[drive].track/2 - track/2;
473 	prb = ciab.prb;
474 	prb |= DSKSIDE | DSKDIREC;
475 	if (track % 2 != 0)
476 		prb &= ~DSKSIDE;
477 	if (cnt < 0) {
478 		cnt = - cnt;
479 		prb &= ~DSKDIREC;
480 	}
481 	ciab.prb = prb;
482 	if (track % 2 != unit[drive].track % 2)
483 		ms_delay (unit[drive].type->side_time);
484 	unit[drive].track = track;
485 	if (cnt == 0) {
486 		rel_fdc();
487 		fd_deselect(drive);
488 		return 1;
489 	}
490 	do {
491 		prb &= ~DSKSTEP;
492 		ciab.prb = prb;
493 		prb |= DSKSTEP;
494 		udelay (1);
495 		ciab.prb = prb;
496 		ms_delay (unit[drive].type->step_delay);
497 	} while (--cnt != 0);
498 	ms_delay (unit[drive].type->settle_time);
499 
500 	rel_fdc();
501 	fd_deselect(drive);
502 	return 1;
503 }
504 
505 static unsigned long fd_get_drive_id(int drive)
506 {
507 	int i;
508 	ulong id = 0;
509 
510   	drive&=3;
511   	get_fdc(drive);
512 	/* set up for ID */
513 	MOTOR_ON;
514 	udelay(2);
515 	SELECT(SELMASK(drive));
516 	udelay(2);
517 	DESELECT(SELMASK(drive));
518 	udelay(2);
519 	MOTOR_OFF;
520 	udelay(2);
521 	SELECT(SELMASK(drive));
522 	udelay(2);
523 	DESELECT(SELMASK(drive));
524 	udelay(2);
525 
526 	/* loop and read disk ID */
527 	for (i=0; i<32; i++) {
528 		SELECT(SELMASK(drive));
529 		udelay(2);
530 
531 		/* read and store value of DSKRDY */
532 		id <<= 1;
533 		id |= (ciaa.pra & DSKRDY) ? 0 : 1;	/* cia regs are low-active! */
534 
535 		DESELECT(SELMASK(drive));
536 	}
537 
538 	rel_fdc();
539 
540         /*
541          * RB: At least A500/A2000's df0: don't identify themselves.
542          * As every (real) Amiga has at least a 3.5" DD drive as df0:
543          * we default to that if df0: doesn't identify as a certain
544          * type.
545          */
546         if(drive == 0 && id == FD_NODRIVE)
547 	{
548                 id = fd_def_df0;
549                 printk(KERN_NOTICE "fd: drive 0 didn't identify, setting default %08lx\n", (ulong)fd_def_df0);
550 	}
551 	/* return the ID value */
552 	return (id);
553 }
554 
555 static irqreturn_t fd_block_done(int irq, void *dummy)
556 {
557 	if (block_flag)
558 		custom.dsklen = 0x4000;
559 
560 	if (block_flag == 2) { /* writing */
561 		writepending = 2;
562 		post_write_timer.expires = jiffies + 1; /* at least 2 ms */
563 		post_write_timer_drive = selected;
564 		add_timer(&post_write_timer);
565 	}
566 	else {                /* reading */
567 		block_flag = 0;
568 		wake_up (&wait_fd_block);
569 	}
570 	return IRQ_HANDLED;
571 }
572 
573 static void raw_read(int drive)
574 {
575 	drive&=3;
576 	get_fdc(drive);
577 	wait_event(wait_fd_block, !block_flag);
578 	fd_select(drive);
579 	/* setup adkcon bits correctly */
580 	custom.adkcon = ADK_MSBSYNC;
581 	custom.adkcon = ADK_SETCLR|ADK_WORDSYNC|ADK_FAST;
582 
583 	custom.dsksync = MFM_SYNC;
584 
585 	custom.dsklen = 0;
586 	custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
587 	custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
588 	custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
589 
590 	block_flag = 1;
591 
592 	wait_event(wait_fd_block, !block_flag);
593 
594 	custom.dsklen = 0;
595 	fd_deselect(drive);
596 	rel_fdc();
597 }
598 
599 static int raw_write(int drive)
600 {
601 	ushort adk;
602 
603 	drive&=3;
604 	get_fdc(drive); /* corresponds to rel_fdc() in post_write() */
605 	if ((ciaa.pra & DSKPROT) == 0) {
606 		rel_fdc();
607 		return 0;
608 	}
609 	wait_event(wait_fd_block, !block_flag);
610 	fd_select(drive);
611 	/* clear adkcon bits */
612 	custom.adkcon = ADK_PRECOMP1|ADK_PRECOMP0|ADK_WORDSYNC|ADK_MSBSYNC;
613 	/* set appropriate adkcon bits */
614 	adk = ADK_SETCLR|ADK_FAST;
615 	if ((ulong)unit[drive].track >= unit[drive].type->precomp2)
616 		adk |= ADK_PRECOMP1;
617 	else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)
618 		adk |= ADK_PRECOMP0;
619 	custom.adkcon = adk;
620 
621 	custom.dsklen = DSKLEN_WRITE;
622 	custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
623 	custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
624 	custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
625 
626 	block_flag = 2;
627 	return 1;
628 }
629 
630 /*
631  * to be called at least 2ms after the write has finished but before any
632  * other access to the hardware.
633  */
634 static void post_write (unsigned long drive)
635 {
636 #ifdef DEBUG
637 	printk("post_write for drive %ld\n",drive);
638 #endif
639 	drive &= 3;
640 	custom.dsklen = 0;
641 	block_flag = 0;
642 	writepending = 0;
643 	writefromint = 0;
644 	unit[drive].dirty = 0;
645 	wake_up(&wait_fd_block);
646 	fd_deselect(drive);
647 	rel_fdc(); /* corresponds to get_fdc() in raw_write */
648 }
649 
650 static void post_write_callback(struct timer_list *timer)
651 {
652 	post_write(post_write_timer_drive);
653 }
654 
655 /*
656  * The following functions are to convert the block contents into raw data
657  * written to disk and vice versa.
658  * (Add other formats here ;-))
659  */
660 
661 static unsigned long scan_sync(unsigned long raw, unsigned long end)
662 {
663 	ushort *ptr = (ushort *)raw, *endp = (ushort *)end;
664 
665 	while (ptr < endp && *ptr++ != 0x4489)
666 		;
667 	if (ptr < endp) {
668 		while (*ptr == 0x4489 && ptr < endp)
669 			ptr++;
670 		return (ulong)ptr;
671 	}
672 	return 0;
673 }
674 
675 static inline unsigned long checksum(unsigned long *addr, int len)
676 {
677 	unsigned long csum = 0;
678 
679 	len /= sizeof(*addr);
680 	while (len-- > 0)
681 		csum ^= *addr++;
682 	csum = ((csum>>1) & 0x55555555)  ^  (csum & 0x55555555);
683 
684 	return csum;
685 }
686 
687 static unsigned long decode (unsigned long *data, unsigned long *raw,
688 			     int len)
689 {
690 	ulong *odd, *even;
691 
692 	/* convert length from bytes to longwords */
693 	len >>= 2;
694 	odd = raw;
695 	even = odd + len;
696 
697 	/* prepare return pointer */
698 	raw += len * 2;
699 
700 	do {
701 		*data++ = ((*odd++ & 0x55555555) << 1) | (*even++ & 0x55555555);
702 	} while (--len != 0);
703 
704 	return (ulong)raw;
705 }
706 
707 struct header {
708 	unsigned char magic;
709 	unsigned char track;
710 	unsigned char sect;
711 	unsigned char ord;
712 	unsigned char labels[16];
713 	unsigned long hdrchk;
714 	unsigned long datachk;
715 };
716 
717 static int amiga_read(int drive)
718 {
719 	unsigned long raw;
720 	unsigned long end;
721 	int scnt;
722 	unsigned long csum;
723 	struct header hdr;
724 
725 	drive&=3;
726 	raw = (long) raw_buf;
727 	end = raw + unit[drive].type->read_size;
728 
729 	for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
730 		if (!(raw = scan_sync(raw, end))) {
731 			printk (KERN_INFO "can't find sync for sector %d\n", scnt);
732 			return MFM_NOSYNC;
733 		}
734 
735 		raw = decode ((ulong *)&hdr.magic, (ulong *)raw, 4);
736 		raw = decode ((ulong *)&hdr.labels, (ulong *)raw, 16);
737 		raw = decode ((ulong *)&hdr.hdrchk, (ulong *)raw, 4);
738 		raw = decode ((ulong *)&hdr.datachk, (ulong *)raw, 4);
739 		csum = checksum((ulong *)&hdr,
740 				(char *)&hdr.hdrchk-(char *)&hdr);
741 
742 #ifdef DEBUG
743 		printk ("(%x,%d,%d,%d) (%lx,%lx,%lx,%lx) %lx %lx\n",
744 			hdr.magic, hdr.track, hdr.sect, hdr.ord,
745 			*(ulong *)&hdr.labels[0], *(ulong *)&hdr.labels[4],
746 			*(ulong *)&hdr.labels[8], *(ulong *)&hdr.labels[12],
747 			hdr.hdrchk, hdr.datachk);
748 #endif
749 
750 		if (hdr.hdrchk != csum) {
751 			printk(KERN_INFO "MFM_HEADER: %08lx,%08lx\n", hdr.hdrchk, csum);
752 			return MFM_HEADER;
753 		}
754 
755 		/* verify track */
756 		if (hdr.track != unit[drive].track) {
757 			printk(KERN_INFO "MFM_TRACK: %d, %d\n", hdr.track, unit[drive].track);
758 			return MFM_TRACK;
759 		}
760 
761 		raw = decode ((ulong *)(unit[drive].trackbuf + hdr.sect*512),
762 			      (ulong *)raw, 512);
763 		csum = checksum((ulong *)(unit[drive].trackbuf + hdr.sect*512), 512);
764 
765 		if (hdr.datachk != csum) {
766 			printk(KERN_INFO "MFM_DATA: (%x:%d:%d:%d) sc=%d %lx, %lx\n",
767 			       hdr.magic, hdr.track, hdr.sect, hdr.ord, scnt,
768 			       hdr.datachk, csum);
769 			printk (KERN_INFO "data=(%lx,%lx,%lx,%lx)\n",
770 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[0],
771 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[1],
772 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[2],
773 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[3]);
774 			return MFM_DATA;
775 		}
776 	}
777 
778 	return 0;
779 }
780 
781 static void encode(unsigned long data, unsigned long *dest)
782 {
783 	unsigned long data2;
784 
785 	data &= 0x55555555;
786 	data2 = data ^ 0x55555555;
787 	data |= ((data2 >> 1) | 0x80000000) & (data2 << 1);
788 
789 	if (*(dest - 1) & 0x00000001)
790 		data &= 0x7FFFFFFF;
791 
792 	*dest = data;
793 }
794 
795 static void encode_block(unsigned long *dest, unsigned long *src, int len)
796 {
797 	int cnt, to_cnt = 0;
798 	unsigned long data;
799 
800 	/* odd bits */
801 	for (cnt = 0; cnt < len / 4; cnt++) {
802 		data = src[cnt] >> 1;
803 		encode(data, dest + to_cnt++);
804 	}
805 
806 	/* even bits */
807 	for (cnt = 0; cnt < len / 4; cnt++) {
808 		data = src[cnt];
809 		encode(data, dest + to_cnt++);
810 	}
811 }
812 
813 static unsigned long *putsec(int disk, unsigned long *raw, int cnt)
814 {
815 	struct header hdr;
816 	int i;
817 
818 	disk&=3;
819 	*raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;
820 	raw++;
821 	*raw++ = 0x44894489;
822 
823 	hdr.magic = 0xFF;
824 	hdr.track = unit[disk].track;
825 	hdr.sect = cnt;
826 	hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;
827 	for (i = 0; i < 16; i++)
828 		hdr.labels[i] = 0;
829 	hdr.hdrchk = checksum((ulong *)&hdr,
830 			      (char *)&hdr.hdrchk-(char *)&hdr);
831 	hdr.datachk = checksum((ulong *)(unit[disk].trackbuf+cnt*512), 512);
832 
833 	encode_block(raw, (ulong *)&hdr.magic, 4);
834 	raw += 2;
835 	encode_block(raw, (ulong *)&hdr.labels, 16);
836 	raw += 8;
837 	encode_block(raw, (ulong *)&hdr.hdrchk, 4);
838 	raw += 2;
839 	encode_block(raw, (ulong *)&hdr.datachk, 4);
840 	raw += 2;
841 	encode_block(raw, (ulong *)(unit[disk].trackbuf+cnt*512), 512);
842 	raw += 256;
843 
844 	return raw;
845 }
846 
847 static void amiga_write(int disk)
848 {
849 	unsigned int cnt;
850 	unsigned long *ptr = (unsigned long *)raw_buf;
851 
852 	disk&=3;
853 	/* gap space */
854 	for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)
855 		*ptr++ = 0xaaaaaaaa;
856 
857 	/* sectors */
858 	for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
859 		ptr = putsec (disk, ptr, cnt);
860 	*(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;
861 }
862 
863 
864 struct dos_header {
865 	unsigned char track,   /* 0-80 */
866 		side,    /* 0-1 */
867 		sec,     /* 0-...*/
868 		len_desc;/* 2 */
869 	unsigned short crc;     /* on 68000 we got an alignment problem,
870 				   but this compiler solves it  by adding silently
871 				   adding a pad byte so data won't fit
872 				   and this took about 3h to discover.... */
873 	unsigned char gap1[22];     /* for longword-alignedness (0x4e) */
874 };
875 
876 /* crc routines are borrowed from the messydos-handler  */
877 
878 /* excerpt from the messydos-device
879 ; The CRC is computed not only over the actual data, but including
880 ; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
881 ; As we don't read or encode these fields into our buffers, we have to
882 ; preload the registers containing the CRC with the values they would have
883 ; after stepping over these fields.
884 ;
885 ; How CRCs "really" work:
886 ;
887 ; First, you should regard a bitstring as a series of coefficients of
888 ; polynomials. We calculate with these polynomials in modulo-2
889 ; arithmetic, in which both add and subtract are done the same as
890 ; exclusive-or. Now, we modify our data (a very long polynomial) in
891 ; such a way that it becomes divisible by the CCITT-standard 16-bit
892 ;		 16   12   5
893 ; polynomial:	x  + x	+ x + 1, represented by $11021. The easiest
894 ; way to do this would be to multiply (using proper arithmetic) our
895 ; datablock with $11021. So we have:
896 ;   data * $11021		 =
897 ;   data * ($10000 + $1021)      =
898 ;   data * $10000 + data * $1021
899 ; The left part of this is simple: Just add two 0 bytes. But then
900 ; the right part (data $1021) remains difficult and even could have
901 ; a carry into the left part. The solution is to use a modified
902 ; multiplication, which has a result that is not correct, but with
903 ; a difference of any multiple of $11021. We then only need to keep
904 ; the 16 least significant bits of the result.
905 ;
906 ; The following algorithm does this for us:
907 ;
908 ;   unsigned char *data, c, crclo, crchi;
909 ;   while (not done) {
910 ;	c = *data++ + crchi;
911 ;	crchi = (@ c) >> 8 + crclo;
912 ;	crclo = @ c;
913 ;   }
914 ;
915 ; Remember, + is done with EOR, the @ operator is in two tables (high
916 ; and low byte separately), which is calculated as
917 ;
918 ;      $1021 * (c & $F0)
919 ;  xor $1021 * (c & $0F)
920 ;  xor $1021 * (c >> 4)         (* is regular multiplication)
921 ;
922 ;
923 ; Anyway, the end result is the same as the remainder of the division of
924 ; the data by $11021. I am afraid I need to study theory a bit more...
925 
926 
927 my only works was to code this from manx to C....
928 
929 */
930 
931 static ushort dos_crc(void * data_a3, int data_d0, int data_d1, int data_d3)
932 {
933 	static unsigned char CRCTable1[] = {
934 		0x00,0x10,0x20,0x30,0x40,0x50,0x60,0x70,0x81,0x91,0xa1,0xb1,0xc1,0xd1,0xe1,0xf1,
935 		0x12,0x02,0x32,0x22,0x52,0x42,0x72,0x62,0x93,0x83,0xb3,0xa3,0xd3,0xc3,0xf3,0xe3,
936 		0x24,0x34,0x04,0x14,0x64,0x74,0x44,0x54,0xa5,0xb5,0x85,0x95,0xe5,0xf5,0xc5,0xd5,
937 		0x36,0x26,0x16,0x06,0x76,0x66,0x56,0x46,0xb7,0xa7,0x97,0x87,0xf7,0xe7,0xd7,0xc7,
938 		0x48,0x58,0x68,0x78,0x08,0x18,0x28,0x38,0xc9,0xd9,0xe9,0xf9,0x89,0x99,0xa9,0xb9,
939 		0x5a,0x4a,0x7a,0x6a,0x1a,0x0a,0x3a,0x2a,0xdb,0xcb,0xfb,0xeb,0x9b,0x8b,0xbb,0xab,
940 		0x6c,0x7c,0x4c,0x5c,0x2c,0x3c,0x0c,0x1c,0xed,0xfd,0xcd,0xdd,0xad,0xbd,0x8d,0x9d,
941 		0x7e,0x6e,0x5e,0x4e,0x3e,0x2e,0x1e,0x0e,0xff,0xef,0xdf,0xcf,0xbf,0xaf,0x9f,0x8f,
942 		0x91,0x81,0xb1,0xa1,0xd1,0xc1,0xf1,0xe1,0x10,0x00,0x30,0x20,0x50,0x40,0x70,0x60,
943 		0x83,0x93,0xa3,0xb3,0xc3,0xd3,0xe3,0xf3,0x02,0x12,0x22,0x32,0x42,0x52,0x62,0x72,
944 		0xb5,0xa5,0x95,0x85,0xf5,0xe5,0xd5,0xc5,0x34,0x24,0x14,0x04,0x74,0x64,0x54,0x44,
945 		0xa7,0xb7,0x87,0x97,0xe7,0xf7,0xc7,0xd7,0x26,0x36,0x06,0x16,0x66,0x76,0x46,0x56,
946 		0xd9,0xc9,0xf9,0xe9,0x99,0x89,0xb9,0xa9,0x58,0x48,0x78,0x68,0x18,0x08,0x38,0x28,
947 		0xcb,0xdb,0xeb,0xfb,0x8b,0x9b,0xab,0xbb,0x4a,0x5a,0x6a,0x7a,0x0a,0x1a,0x2a,0x3a,
948 		0xfd,0xed,0xdd,0xcd,0xbd,0xad,0x9d,0x8d,0x7c,0x6c,0x5c,0x4c,0x3c,0x2c,0x1c,0x0c,
949 		0xef,0xff,0xcf,0xdf,0xaf,0xbf,0x8f,0x9f,0x6e,0x7e,0x4e,0x5e,0x2e,0x3e,0x0e,0x1e
950 	};
951 
952 	static unsigned char CRCTable2[] = {
953 		0x00,0x21,0x42,0x63,0x84,0xa5,0xc6,0xe7,0x08,0x29,0x4a,0x6b,0x8c,0xad,0xce,0xef,
954 		0x31,0x10,0x73,0x52,0xb5,0x94,0xf7,0xd6,0x39,0x18,0x7b,0x5a,0xbd,0x9c,0xff,0xde,
955 		0x62,0x43,0x20,0x01,0xe6,0xc7,0xa4,0x85,0x6a,0x4b,0x28,0x09,0xee,0xcf,0xac,0x8d,
956 		0x53,0x72,0x11,0x30,0xd7,0xf6,0x95,0xb4,0x5b,0x7a,0x19,0x38,0xdf,0xfe,0x9d,0xbc,
957 		0xc4,0xe5,0x86,0xa7,0x40,0x61,0x02,0x23,0xcc,0xed,0x8e,0xaf,0x48,0x69,0x0a,0x2b,
958 		0xf5,0xd4,0xb7,0x96,0x71,0x50,0x33,0x12,0xfd,0xdc,0xbf,0x9e,0x79,0x58,0x3b,0x1a,
959 		0xa6,0x87,0xe4,0xc5,0x22,0x03,0x60,0x41,0xae,0x8f,0xec,0xcd,0x2a,0x0b,0x68,0x49,
960 		0x97,0xb6,0xd5,0xf4,0x13,0x32,0x51,0x70,0x9f,0xbe,0xdd,0xfc,0x1b,0x3a,0x59,0x78,
961 		0x88,0xa9,0xca,0xeb,0x0c,0x2d,0x4e,0x6f,0x80,0xa1,0xc2,0xe3,0x04,0x25,0x46,0x67,
962 		0xb9,0x98,0xfb,0xda,0x3d,0x1c,0x7f,0x5e,0xb1,0x90,0xf3,0xd2,0x35,0x14,0x77,0x56,
963 		0xea,0xcb,0xa8,0x89,0x6e,0x4f,0x2c,0x0d,0xe2,0xc3,0xa0,0x81,0x66,0x47,0x24,0x05,
964 		0xdb,0xfa,0x99,0xb8,0x5f,0x7e,0x1d,0x3c,0xd3,0xf2,0x91,0xb0,0x57,0x76,0x15,0x34,
965 		0x4c,0x6d,0x0e,0x2f,0xc8,0xe9,0x8a,0xab,0x44,0x65,0x06,0x27,0xc0,0xe1,0x82,0xa3,
966 		0x7d,0x5c,0x3f,0x1e,0xf9,0xd8,0xbb,0x9a,0x75,0x54,0x37,0x16,0xf1,0xd0,0xb3,0x92,
967 		0x2e,0x0f,0x6c,0x4d,0xaa,0x8b,0xe8,0xc9,0x26,0x07,0x64,0x45,0xa2,0x83,0xe0,0xc1,
968 		0x1f,0x3e,0x5d,0x7c,0x9b,0xba,0xd9,0xf8,0x17,0x36,0x55,0x74,0x93,0xb2,0xd1,0xf0
969 	};
970 
971 /* look at the asm-code - what looks in C a bit strange is almost as good as handmade */
972 	register int i;
973 	register unsigned char *CRCT1, *CRCT2, *data, c, crch, crcl;
974 
975 	CRCT1=CRCTable1;
976 	CRCT2=CRCTable2;
977 	data=data_a3;
978 	crcl=data_d1;
979 	crch=data_d0;
980 	for (i=data_d3; i>=0; i--) {
981 		c = (*data++) ^ crch;
982 		crch = CRCT1[c] ^ crcl;
983 		crcl = CRCT2[c];
984 	}
985 	return (crch<<8)|crcl;
986 }
987 
988 static inline ushort dos_hdr_crc (struct dos_header *hdr)
989 {
990 	return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */
991 }
992 
993 static inline ushort dos_data_crc(unsigned char *data)
994 {
995 	return dos_crc(data, 0xe2, 0x95 ,511); /* precomputed magic */
996 }
997 
998 static inline unsigned char dos_decode_byte(ushort word)
999 {
1000 	register ushort w2;
1001 	register unsigned char byte;
1002 	register unsigned char *dec = mfmdecode;
1003 
1004 	w2=word;
1005 	w2>>=8;
1006 	w2&=127;
1007 	byte = dec[w2];
1008 	byte <<= 4;
1009 	w2 = word & 127;
1010 	byte |= dec[w2];
1011 	return byte;
1012 }
1013 
1014 static unsigned long dos_decode(unsigned char *data, unsigned short *raw, int len)
1015 {
1016 	int i;
1017 
1018 	for (i = 0; i < len; i++)
1019 		*data++=dos_decode_byte(*raw++);
1020 	return ((ulong)raw);
1021 }
1022 
1023 #ifdef DEBUG
1024 static void dbg(unsigned long ptr)
1025 {
1026 	printk("raw data @%08lx: %08lx, %08lx ,%08lx, %08lx\n", ptr,
1027 	       ((ulong *)ptr)[0], ((ulong *)ptr)[1],
1028 	       ((ulong *)ptr)[2], ((ulong *)ptr)[3]);
1029 }
1030 #endif
1031 
1032 static int dos_read(int drive)
1033 {
1034 	unsigned long end;
1035 	unsigned long raw;
1036 	int scnt;
1037 	unsigned short crc,data_crc[2];
1038 	struct dos_header hdr;
1039 
1040 	drive&=3;
1041 	raw = (long) raw_buf;
1042 	end = raw + unit[drive].type->read_size;
1043 
1044 	for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
1045 		do { /* search for the right sync of each sec-hdr */
1046 			if (!(raw = scan_sync (raw, end))) {
1047 				printk(KERN_INFO "dos_read: no hdr sync on "
1048 				       "track %d, unit %d for sector %d\n",
1049 				       unit[drive].track,drive,scnt);
1050 				return MFM_NOSYNC;
1051 			}
1052 #ifdef DEBUG
1053 			dbg(raw);
1054 #endif
1055 		} while (*((ushort *)raw)!=0x5554); /* loop usually only once done */
1056 		raw+=2; /* skip over headermark */
1057 		raw = dos_decode((unsigned char *)&hdr,(ushort *) raw,8);
1058 		crc = dos_hdr_crc(&hdr);
1059 
1060 #ifdef DEBUG
1061 		printk("(%3d,%d,%2d,%d) %x\n", hdr.track, hdr.side,
1062 		       hdr.sec, hdr.len_desc, hdr.crc);
1063 #endif
1064 
1065 		if (crc != hdr.crc) {
1066 			printk(KERN_INFO "dos_read: MFM_HEADER %04x,%04x\n",
1067 			       hdr.crc, crc);
1068 			return MFM_HEADER;
1069 		}
1070 		if (hdr.track != unit[drive].track/unit[drive].type->heads) {
1071 			printk(KERN_INFO "dos_read: MFM_TRACK %d, %d\n",
1072 			       hdr.track,
1073 			       unit[drive].track/unit[drive].type->heads);
1074 			return MFM_TRACK;
1075 		}
1076 
1077 		if (hdr.side != unit[drive].track%unit[drive].type->heads) {
1078 			printk(KERN_INFO "dos_read: MFM_SIDE %d, %d\n",
1079 			       hdr.side,
1080 			       unit[drive].track%unit[drive].type->heads);
1081 			return MFM_TRACK;
1082 		}
1083 
1084 		if (hdr.len_desc != 2) {
1085 			printk(KERN_INFO "dos_read: unknown sector len "
1086 			       "descriptor %d\n", hdr.len_desc);
1087 			return MFM_DATA;
1088 		}
1089 #ifdef DEBUG
1090 		printk("hdr accepted\n");
1091 #endif
1092 		if (!(raw = scan_sync (raw, end))) {
1093 			printk(KERN_INFO "dos_read: no data sync on track "
1094 			       "%d, unit %d for sector%d, disk sector %d\n",
1095 			       unit[drive].track, drive, scnt, hdr.sec);
1096 			return MFM_NOSYNC;
1097 		}
1098 #ifdef DEBUG
1099 		dbg(raw);
1100 #endif
1101 
1102 		if (*((ushort *)raw)!=0x5545) {
1103 			printk(KERN_INFO "dos_read: no data mark after "
1104 			       "sync (%d,%d,%d,%d) sc=%d\n",
1105 			       hdr.track,hdr.side,hdr.sec,hdr.len_desc,scnt);
1106 			return MFM_NOSYNC;
1107 		}
1108 
1109 		raw+=2;  /* skip data mark (included in checksum) */
1110 		raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 512);
1111 		raw = dos_decode((unsigned char  *)data_crc,(ushort *) raw,4);
1112 		crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);
1113 
1114 		if (crc != data_crc[0]) {
1115 			printk(KERN_INFO "dos_read: MFM_DATA (%d,%d,%d,%d) "
1116 			       "sc=%d, %x %x\n", hdr.track, hdr.side,
1117 			       hdr.sec, hdr.len_desc, scnt,data_crc[0], crc);
1118 			printk(KERN_INFO "data=(%lx,%lx,%lx,%lx,...)\n",
1119 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],
1120 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],
1121 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],
1122 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);
1123 			return MFM_DATA;
1124 		}
1125 	}
1126 	return 0;
1127 }
1128 
1129 static inline ushort dos_encode_byte(unsigned char byte)
1130 {
1131 	register unsigned char *enc, b2, b1;
1132 	register ushort word;
1133 
1134 	enc=mfmencode;
1135 	b1=byte;
1136 	b2=b1>>4;
1137 	b1&=15;
1138 	word=enc[b2] <<8 | enc [b1];
1139 	return (word|((word&(256|64)) ? 0: 128));
1140 }
1141 
1142 static void dos_encode_block(ushort *dest, unsigned char *src, int len)
1143 {
1144 	int i;
1145 
1146 	for (i = 0; i < len; i++) {
1147 		*dest=dos_encode_byte(*src++);
1148 		*dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;
1149 		dest++;
1150 	}
1151 }
1152 
1153 static unsigned long *ms_putsec(int drive, unsigned long *raw, int cnt)
1154 {
1155 	static struct dos_header hdr={0,0,0,2,0,
1156 	  {78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78}};
1157 	int i;
1158 	static ushort crc[2]={0,0x4e4e};
1159 
1160 	drive&=3;
1161 /* id gap 1 */
1162 /* the MFM word before is always 9254 */
1163 	for(i=0;i<6;i++)
1164 		*raw++=0xaaaaaaaa;
1165 /* 3 sync + 1 headermark */
1166 	*raw++=0x44894489;
1167 	*raw++=0x44895554;
1168 
1169 /* fill in the variable parts of the header */
1170 	hdr.track=unit[drive].track/unit[drive].type->heads;
1171 	hdr.side=unit[drive].track%unit[drive].type->heads;
1172 	hdr.sec=cnt+1;
1173 	hdr.crc=dos_hdr_crc(&hdr);
1174 
1175 /* header (without "magic") and id gap 2*/
1176 	dos_encode_block((ushort *)raw,(unsigned char *) &hdr.track,28);
1177 	raw+=14;
1178 
1179 /*id gap 3 */
1180 	for(i=0;i<6;i++)
1181 		*raw++=0xaaaaaaaa;
1182 
1183 /* 3 syncs and 1 datamark */
1184 	*raw++=0x44894489;
1185 	*raw++=0x44895545;
1186 
1187 /* data */
1188 	dos_encode_block((ushort *)raw,
1189 			 (unsigned char *)unit[drive].trackbuf+cnt*512,512);
1190 	raw+=256;
1191 
1192 /*data crc + jd's special gap (long words :-/) */
1193 	crc[0]=dos_data_crc(unit[drive].trackbuf+cnt*512);
1194 	dos_encode_block((ushort *) raw,(unsigned char *)crc,4);
1195 	raw+=2;
1196 
1197 /* data gap */
1198 	for(i=0;i<38;i++)
1199 		*raw++=0x92549254;
1200 
1201 	return raw; /* wrote 652 MFM words */
1202 }
1203 
1204 static void dos_write(int disk)
1205 {
1206 	int cnt;
1207 	unsigned long raw = (unsigned long) raw_buf;
1208 	unsigned long *ptr=(unsigned long *)raw;
1209 
1210 	disk&=3;
1211 /* really gap4 + indexgap , but we write it first and round it up */
1212 	for (cnt=0;cnt<425;cnt++)
1213 		*ptr++=0x92549254;
1214 
1215 /* the following is just guessed */
1216 	if (unit[disk].type->sect_mult==2)  /* check for HD-Disks */
1217 		for(cnt=0;cnt<473;cnt++)
1218 			*ptr++=0x92549254;
1219 
1220 /* now the index marks...*/
1221 	for (cnt=0;cnt<20;cnt++)
1222 		*ptr++=0x92549254;
1223 	for (cnt=0;cnt<6;cnt++)
1224 		*ptr++=0xaaaaaaaa;
1225 	*ptr++=0x52245224;
1226 	*ptr++=0x52245552;
1227 	for (cnt=0;cnt<20;cnt++)
1228 		*ptr++=0x92549254;
1229 
1230 /* sectors */
1231 	for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
1232 		ptr=ms_putsec(disk,ptr,cnt);
1233 
1234 	*(ushort *)ptr = 0xaaa8; /* MFM word before is always 0x9254 */
1235 }
1236 
1237 /*
1238  * Here comes the high level stuff (i.e. the filesystem interface)
1239  * and helper functions.
1240  * Normally this should be the only part that has to be adapted to
1241  * different kernel versions.
1242  */
1243 
1244 /* FIXME: this assumes the drive is still spinning -
1245  * which is only true if we complete writing a track within three seconds
1246  */
1247 static void flush_track_callback(struct timer_list *timer)
1248 {
1249 	unsigned long nr = ((unsigned long)timer -
1250 			       (unsigned long)&flush_track_timer[0]) /
1251 					sizeof(flush_track_timer[0]);
1252 
1253 	nr&=3;
1254 	writefromint = 1;
1255 	if (!try_fdc(nr)) {
1256 		/* we might block in an interrupt, so try again later */
1257 		flush_track_timer[nr].expires = jiffies + 1;
1258 		add_timer(flush_track_timer + nr);
1259 		return;
1260 	}
1261 	get_fdc(nr);
1262 	(*unit[nr].dtype->write_fkt)(nr);
1263 	if (!raw_write(nr)) {
1264 		printk (KERN_NOTICE "floppy disk write protected\n");
1265 		writefromint = 0;
1266 		writepending = 0;
1267 	}
1268 	rel_fdc();
1269 }
1270 
1271 static int non_int_flush_track (unsigned long nr)
1272 {
1273 	unsigned long flags;
1274 
1275 	nr&=3;
1276 	writefromint = 0;
1277 	del_timer(&post_write_timer);
1278 	get_fdc(nr);
1279 	if (!fd_motor_on(nr)) {
1280 		writepending = 0;
1281 		rel_fdc();
1282 		return 0;
1283 	}
1284 	local_irq_save(flags);
1285 	if (writepending != 2) {
1286 		local_irq_restore(flags);
1287 		(*unit[nr].dtype->write_fkt)(nr);
1288 		if (!raw_write(nr)) {
1289 			printk (KERN_NOTICE "floppy disk write protected "
1290 				"in write!\n");
1291 			writepending = 0;
1292 			return 0;
1293 		}
1294 		wait_event(wait_fd_block, block_flag != 2);
1295 	}
1296 	else {
1297 		local_irq_restore(flags);
1298 		ms_delay(2); /* 2 ms post_write delay */
1299 		post_write(nr);
1300 	}
1301 	rel_fdc();
1302 	return 1;
1303 }
1304 
1305 static int get_track(int drive, int track)
1306 {
1307 	int error, errcnt;
1308 
1309 	drive&=3;
1310 	if (unit[drive].track == track)
1311 		return 0;
1312 	get_fdc(drive);
1313 	if (!fd_motor_on(drive)) {
1314 		rel_fdc();
1315 		return -1;
1316 	}
1317 
1318 	if (unit[drive].dirty == 1) {
1319 		del_timer (flush_track_timer + drive);
1320 		non_int_flush_track (drive);
1321 	}
1322 	errcnt = 0;
1323 	while (errcnt < MAX_ERRORS) {
1324 		if (!fd_seek(drive, track))
1325 			return -1;
1326 		raw_read(drive);
1327 		error = (*unit[drive].dtype->read_fkt)(drive);
1328 		if (error == 0) {
1329 			rel_fdc();
1330 			return 0;
1331 		}
1332 		/* Read Error Handling: recalibrate and try again */
1333 		unit[drive].track = -1;
1334 		errcnt++;
1335 	}
1336 	rel_fdc();
1337 	return -1;
1338 }
1339 
1340 /*
1341  * Round-robin between our available drives, doing one request from each
1342  */
1343 static struct request *set_next_request(void)
1344 {
1345 	struct request_queue *q;
1346 	int cnt = FD_MAX_UNITS;
1347 	struct request *rq = NULL;
1348 
1349 	/* Find next queue we can dispatch from */
1350 	fdc_queue = fdc_queue + 1;
1351 	if (fdc_queue == FD_MAX_UNITS)
1352 		fdc_queue = 0;
1353 
1354 	for(cnt = FD_MAX_UNITS; cnt > 0; cnt--) {
1355 
1356 		if (unit[fdc_queue].type->code == FD_NODRIVE) {
1357 			if (++fdc_queue == FD_MAX_UNITS)
1358 				fdc_queue = 0;
1359 			continue;
1360 		}
1361 
1362 		q = unit[fdc_queue].gendisk->queue;
1363 		if (q) {
1364 			rq = blk_fetch_request(q);
1365 			if (rq)
1366 				break;
1367 		}
1368 
1369 		if (++fdc_queue == FD_MAX_UNITS)
1370 			fdc_queue = 0;
1371 	}
1372 
1373 	return rq;
1374 }
1375 
1376 static void redo_fd_request(void)
1377 {
1378 	struct request *rq;
1379 	unsigned int cnt, block, track, sector;
1380 	int drive;
1381 	struct amiga_floppy_struct *floppy;
1382 	char *data;
1383 	unsigned long flags;
1384 	blk_status_t err;
1385 
1386 next_req:
1387 	rq = set_next_request();
1388 	if (!rq) {
1389 		/* Nothing left to do */
1390 		return;
1391 	}
1392 
1393 	floppy = rq->rq_disk->private_data;
1394 	drive = floppy - unit;
1395 
1396 next_segment:
1397 	/* Here someone could investigate to be more efficient */
1398 	for (cnt = 0, err = BLK_STS_OK; cnt < blk_rq_cur_sectors(rq); cnt++) {
1399 #ifdef DEBUG
1400 		printk("fd: sector %ld + %d requested for %s\n",
1401 		       blk_rq_pos(rq), cnt,
1402 		       (rq_data_dir(rq) == READ) ? "read" : "write");
1403 #endif
1404 		block = blk_rq_pos(rq) + cnt;
1405 		if ((int)block > floppy->blocks) {
1406 			err = BLK_STS_IOERR;
1407 			break;
1408 		}
1409 
1410 		track = block / (floppy->dtype->sects * floppy->type->sect_mult);
1411 		sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
1412 		data = bio_data(rq->bio) + 512 * cnt;
1413 #ifdef DEBUG
1414 		printk("access to track %d, sector %d, with buffer at "
1415 		       "0x%08lx\n", track, sector, data);
1416 #endif
1417 
1418 		if (get_track(drive, track) == -1) {
1419 			err = BLK_STS_IOERR;
1420 			break;
1421 		}
1422 
1423 		if (rq_data_dir(rq) == READ) {
1424 			memcpy(data, floppy->trackbuf + sector * 512, 512);
1425 		} else {
1426 			memcpy(floppy->trackbuf + sector * 512, data, 512);
1427 
1428 			/* keep the drive spinning while writes are scheduled */
1429 			if (!fd_motor_on(drive)) {
1430 				err = BLK_STS_IOERR;
1431 				break;
1432 			}
1433 			/*
1434 			 * setup a callback to write the track buffer
1435 			 * after a short (1 tick) delay.
1436 			 */
1437 			local_irq_save(flags);
1438 
1439 			floppy->dirty = 1;
1440 		        /* reset the timer */
1441 			mod_timer (flush_track_timer + drive, jiffies + 1);
1442 			local_irq_restore(flags);
1443 		}
1444 	}
1445 
1446 	if (__blk_end_request_cur(rq, err))
1447 		goto next_segment;
1448 	goto next_req;
1449 }
1450 
1451 static void do_fd_request(struct request_queue * q)
1452 {
1453 	redo_fd_request();
1454 }
1455 
1456 static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1457 {
1458 	int drive = MINOR(bdev->bd_dev) & 3;
1459 
1460 	geo->heads = unit[drive].type->heads;
1461 	geo->sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
1462 	geo->cylinders = unit[drive].type->tracks;
1463 	return 0;
1464 }
1465 
1466 static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
1467 		    unsigned int cmd, unsigned long param)
1468 {
1469 	struct amiga_floppy_struct *p = bdev->bd_disk->private_data;
1470 	int drive = p - unit;
1471 	static struct floppy_struct getprm;
1472 	void __user *argp = (void __user *)param;
1473 
1474 	switch(cmd){
1475 	case FDFMTBEG:
1476 		get_fdc(drive);
1477 		if (fd_ref[drive] > 1) {
1478 			rel_fdc();
1479 			return -EBUSY;
1480 		}
1481 		fsync_bdev(bdev);
1482 		if (fd_motor_on(drive) == 0) {
1483 			rel_fdc();
1484 			return -ENODEV;
1485 		}
1486 		if (fd_calibrate(drive) == 0) {
1487 			rel_fdc();
1488 			return -ENXIO;
1489 		}
1490 		floppy_off(drive);
1491 		rel_fdc();
1492 		break;
1493 	case FDFMTTRK:
1494 		if (param < p->type->tracks * p->type->heads)
1495 		{
1496 			get_fdc(drive);
1497 			if (fd_seek(drive,param) != 0){
1498 				memset(p->trackbuf, FD_FILL_BYTE,
1499 				       p->dtype->sects * p->type->sect_mult * 512);
1500 				non_int_flush_track(drive);
1501 			}
1502 			floppy_off(drive);
1503 			rel_fdc();
1504 		}
1505 		else
1506 			return -EINVAL;
1507 		break;
1508 	case FDFMTEND:
1509 		floppy_off(drive);
1510 		invalidate_bdev(bdev);
1511 		break;
1512 	case FDGETPRM:
1513 		memset((void *)&getprm, 0, sizeof (getprm));
1514 		getprm.track=p->type->tracks;
1515 		getprm.head=p->type->heads;
1516 		getprm.sect=p->dtype->sects * p->type->sect_mult;
1517 		getprm.size=p->blocks;
1518 		if (copy_to_user(argp, &getprm, sizeof(struct floppy_struct)))
1519 			return -EFAULT;
1520 		break;
1521 	case FDSETPRM:
1522 	case FDDEFPRM:
1523 		return -EINVAL;
1524 	case FDFLUSH: /* unconditionally, even if not needed */
1525 		del_timer (flush_track_timer + drive);
1526 		non_int_flush_track(drive);
1527 		break;
1528 #ifdef RAW_IOCTL
1529 	case IOCTL_RAW_TRACK:
1530 		if (copy_to_user(argp, raw_buf, p->type->read_size))
1531 			return -EFAULT;
1532 		else
1533 			return p->type->read_size;
1534 #endif
1535 	default:
1536 		printk(KERN_DEBUG "fd_ioctl: unknown cmd %d for drive %d.",
1537 		       cmd, drive);
1538 		return -ENOSYS;
1539 	}
1540 	return 0;
1541 }
1542 
1543 static int fd_ioctl(struct block_device *bdev, fmode_t mode,
1544 			     unsigned int cmd, unsigned long param)
1545 {
1546 	int ret;
1547 
1548 	mutex_lock(&amiflop_mutex);
1549 	ret = fd_locked_ioctl(bdev, mode, cmd, param);
1550 	mutex_unlock(&amiflop_mutex);
1551 
1552 	return ret;
1553 }
1554 
1555 static void fd_probe(int dev)
1556 {
1557 	unsigned long code;
1558 	int type;
1559 	int drive;
1560 
1561 	drive = dev & 3;
1562 	code = fd_get_drive_id(drive);
1563 
1564 	/* get drive type */
1565 	for (type = 0; type < num_dr_types; type++)
1566 		if (drive_types[type].code == code)
1567 			break;
1568 
1569 	if (type >= num_dr_types) {
1570 		printk(KERN_WARNING "fd_probe: unsupported drive type "
1571 		       "%08lx found\n", code);
1572 		unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */
1573 		return;
1574 	}
1575 
1576 	unit[drive].type = drive_types + type;
1577 	unit[drive].track = -1;
1578 
1579 	unit[drive].disk = -1;
1580 	unit[drive].motor = 0;
1581 	unit[drive].busy = 0;
1582 	unit[drive].status = -1;
1583 }
1584 
1585 /*
1586  * floppy_open check for aliasing (/dev/fd0 can be the same as
1587  * /dev/PS0 etc), and disallows simultaneous access to the same
1588  * drive with different device numbers.
1589  */
1590 static int floppy_open(struct block_device *bdev, fmode_t mode)
1591 {
1592 	int drive = MINOR(bdev->bd_dev) & 3;
1593 	int system =  (MINOR(bdev->bd_dev) & 4) >> 2;
1594 	int old_dev;
1595 	unsigned long flags;
1596 
1597 	mutex_lock(&amiflop_mutex);
1598 	old_dev = fd_device[drive];
1599 
1600 	if (fd_ref[drive] && old_dev != system) {
1601 		mutex_unlock(&amiflop_mutex);
1602 		return -EBUSY;
1603 	}
1604 
1605 	if (mode & (FMODE_READ|FMODE_WRITE)) {
1606 		check_disk_change(bdev);
1607 		if (mode & FMODE_WRITE) {
1608 			int wrprot;
1609 
1610 			get_fdc(drive);
1611 			fd_select (drive);
1612 			wrprot = !(ciaa.pra & DSKPROT);
1613 			fd_deselect (drive);
1614 			rel_fdc();
1615 
1616 			if (wrprot) {
1617 				mutex_unlock(&amiflop_mutex);
1618 				return -EROFS;
1619 			}
1620 		}
1621 	}
1622 
1623 	local_irq_save(flags);
1624 	fd_ref[drive]++;
1625 	fd_device[drive] = system;
1626 	local_irq_restore(flags);
1627 
1628 	unit[drive].dtype=&data_types[system];
1629 	unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
1630 		data_types[system].sects*unit[drive].type->sect_mult;
1631 	set_capacity(unit[drive].gendisk, unit[drive].blocks);
1632 
1633 	printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
1634 	       unit[drive].type->name, data_types[system].name);
1635 
1636 	mutex_unlock(&amiflop_mutex);
1637 	return 0;
1638 }
1639 
1640 static void floppy_release(struct gendisk *disk, fmode_t mode)
1641 {
1642 	struct amiga_floppy_struct *p = disk->private_data;
1643 	int drive = p - unit;
1644 
1645 	mutex_lock(&amiflop_mutex);
1646 	if (unit[drive].dirty == 1) {
1647 		del_timer (flush_track_timer + drive);
1648 		non_int_flush_track (drive);
1649 	}
1650 
1651 	if (!fd_ref[drive]--) {
1652 		printk(KERN_CRIT "floppy_release with fd_ref == 0");
1653 		fd_ref[drive] = 0;
1654 	}
1655 #ifdef MODULE
1656 	floppy_off (drive);
1657 #endif
1658 	mutex_unlock(&amiflop_mutex);
1659 }
1660 
1661 /*
1662  * check_events is never called from an interrupt, so we can relax a bit
1663  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
1664  * to the desired drive, but it will probably not survive the sleep if
1665  * several floppies are used at the same time: thus the loop.
1666  */
1667 static unsigned amiga_check_events(struct gendisk *disk, unsigned int clearing)
1668 {
1669 	struct amiga_floppy_struct *p = disk->private_data;
1670 	int drive = p - unit;
1671 	int changed;
1672 	static int first_time = 1;
1673 
1674 	if (first_time)
1675 		changed = first_time--;
1676 	else {
1677 		get_fdc(drive);
1678 		fd_select (drive);
1679 		changed = !(ciaa.pra & DSKCHANGE);
1680 		fd_deselect (drive);
1681 		rel_fdc();
1682 	}
1683 
1684 	if (changed) {
1685 		fd_probe(drive);
1686 		p->track = -1;
1687 		p->dirty = 0;
1688 		writepending = 0; /* if this was true before, too bad! */
1689 		writefromint = 0;
1690 		return DISK_EVENT_MEDIA_CHANGE;
1691 	}
1692 	return 0;
1693 }
1694 
1695 static const struct block_device_operations floppy_fops = {
1696 	.owner		= THIS_MODULE,
1697 	.open		= floppy_open,
1698 	.release	= floppy_release,
1699 	.ioctl		= fd_ioctl,
1700 	.getgeo		= fd_getgeo,
1701 	.check_events	= amiga_check_events,
1702 };
1703 
1704 static int __init fd_probe_drives(void)
1705 {
1706 	int drive,drives,nomem;
1707 
1708 	printk(KERN_INFO "FD: probing units\nfound ");
1709 	drives=0;
1710 	nomem=0;
1711 	for(drive=0;drive<FD_MAX_UNITS;drive++) {
1712 		struct gendisk *disk;
1713 		fd_probe(drive);
1714 		if (unit[drive].type->code == FD_NODRIVE)
1715 			continue;
1716 		disk = alloc_disk(1);
1717 		if (!disk) {
1718 			unit[drive].type->code = FD_NODRIVE;
1719 			continue;
1720 		}
1721 		unit[drive].gendisk = disk;
1722 
1723 		disk->queue = blk_init_queue(do_fd_request, &amiflop_lock);
1724 		if (!disk->queue) {
1725 			unit[drive].type->code = FD_NODRIVE;
1726 			continue;
1727 		}
1728 
1729 		drives++;
1730 		if ((unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL)) == NULL) {
1731 			printk("no mem for ");
1732 			unit[drive].type = &drive_types[num_dr_types - 1]; /* FD_NODRIVE */
1733 			drives--;
1734 			nomem = 1;
1735 		}
1736 		printk("fd%d ",drive);
1737 		disk->major = FLOPPY_MAJOR;
1738 		disk->first_minor = drive;
1739 		disk->fops = &floppy_fops;
1740 		sprintf(disk->disk_name, "fd%d", drive);
1741 		disk->private_data = &unit[drive];
1742 		set_capacity(disk, 880*2);
1743 		add_disk(disk);
1744 	}
1745 	if ((drives > 0) || (nomem == 0)) {
1746 		if (drives == 0)
1747 			printk("no drives");
1748 		printk("\n");
1749 		return drives;
1750 	}
1751 	printk("\n");
1752 	return -ENOMEM;
1753 }
1754 
1755 static struct kobject *floppy_find(dev_t dev, int *part, void *data)
1756 {
1757 	int drive = *part & 3;
1758 	if (unit[drive].type->code == FD_NODRIVE)
1759 		return NULL;
1760 	*part = 0;
1761 	return get_disk_and_module(unit[drive].gendisk);
1762 }
1763 
1764 static int __init amiga_floppy_probe(struct platform_device *pdev)
1765 {
1766 	int i, ret;
1767 
1768 	if (register_blkdev(FLOPPY_MAJOR,"fd"))
1769 		return -EBUSY;
1770 
1771 	ret = -ENOMEM;
1772 	raw_buf = amiga_chip_alloc(RAW_BUF_SIZE, "Floppy");
1773 	if (!raw_buf) {
1774 		printk("fd: cannot get chip mem buffer\n");
1775 		goto out_blkdev;
1776 	}
1777 
1778 	ret = -EBUSY;
1779 	if (request_irq(IRQ_AMIGA_DSKBLK, fd_block_done, 0, "floppy_dma", NULL)) {
1780 		printk("fd: cannot get irq for dma\n");
1781 		goto out_irq;
1782 	}
1783 
1784 	if (request_irq(IRQ_AMIGA_CIAA_TB, ms_isr, 0, "floppy_timer", NULL)) {
1785 		printk("fd: cannot get irq for timer\n");
1786 		goto out_irq2;
1787 	}
1788 
1789 	ret = -ENODEV;
1790 	if (fd_probe_drives() < 1) /* No usable drives */
1791 		goto out_probe;
1792 
1793 	blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
1794 				floppy_find, NULL, NULL);
1795 
1796 	/* initialize variables */
1797 	timer_setup(&motor_on_timer, motor_on_callback, 0);
1798 	motor_on_timer.expires = 0;
1799 	for (i = 0; i < FD_MAX_UNITS; i++) {
1800 		timer_setup(&motor_off_timer[i], fd_motor_off, 0);
1801 		motor_off_timer[i].expires = 0;
1802 		timer_setup(&flush_track_timer[i], flush_track_callback, 0);
1803 		flush_track_timer[i].expires = 0;
1804 
1805 		unit[i].track = -1;
1806 	}
1807 
1808 	timer_setup(&post_write_timer, post_write_callback, 0);
1809 	post_write_timer.expires = 0;
1810 
1811 	for (i = 0; i < 128; i++)
1812 		mfmdecode[i]=255;
1813 	for (i = 0; i < 16; i++)
1814 		mfmdecode[mfmencode[i]]=i;
1815 
1816 	/* make sure that disk DMA is enabled */
1817 	custom.dmacon = DMAF_SETCLR | DMAF_DISK;
1818 
1819 	/* init ms timer */
1820 	ciaa.crb = 8; /* one-shot, stop */
1821 	return 0;
1822 
1823 out_probe:
1824 	free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1825 out_irq2:
1826 	free_irq(IRQ_AMIGA_DSKBLK, NULL);
1827 out_irq:
1828 	amiga_chip_free(raw_buf);
1829 out_blkdev:
1830 	unregister_blkdev(FLOPPY_MAJOR,"fd");
1831 	return ret;
1832 }
1833 
1834 #if 0 /* not safe to unload */
1835 static int __exit amiga_floppy_remove(struct platform_device *pdev)
1836 {
1837 	int i;
1838 
1839 	for( i = 0; i < FD_MAX_UNITS; i++) {
1840 		if (unit[i].type->code != FD_NODRIVE) {
1841 			struct request_queue *q = unit[i].gendisk->queue;
1842 			del_gendisk(unit[i].gendisk);
1843 			put_disk(unit[i].gendisk);
1844 			kfree(unit[i].trackbuf);
1845 			if (q)
1846 				blk_cleanup_queue(q);
1847 		}
1848 	}
1849 	blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
1850 	free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1851 	free_irq(IRQ_AMIGA_DSKBLK, NULL);
1852 	custom.dmacon = DMAF_DISK; /* disable DMA */
1853 	amiga_chip_free(raw_buf);
1854 	unregister_blkdev(FLOPPY_MAJOR, "fd");
1855 }
1856 #endif
1857 
1858 static struct platform_driver amiga_floppy_driver = {
1859 	.driver   = {
1860 		.name	= "amiga-floppy",
1861 	},
1862 };
1863 
1864 static int __init amiga_floppy_init(void)
1865 {
1866 	return platform_driver_probe(&amiga_floppy_driver, amiga_floppy_probe);
1867 }
1868 
1869 module_init(amiga_floppy_init);
1870 
1871 #ifndef MODULE
1872 static int __init amiga_floppy_setup (char *str)
1873 {
1874 	int n;
1875 	if (!MACH_IS_AMIGA)
1876 		return 0;
1877 	if (!get_option(&str, &n))
1878 		return 0;
1879 	printk (KERN_INFO "amiflop: Setting default df0 to %x\n", n);
1880 	fd_def_df0 = n;
1881 	return 1;
1882 }
1883 
1884 __setup("floppy=", amiga_floppy_setup);
1885 #endif
1886 
1887 MODULE_ALIAS("platform:amiga-floppy");
1888