xref: /openbmc/linux/drivers/block/amiflop.c (revision 63dc02bd)
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 <asm/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 struct timer_list motor_on_timer;
150 static struct timer_list motor_off_timer[FD_MAX_UNITS];
151 static int on_attempts;
152 
153 /* Synchronization of FDC access */
154 /* request loop (trackbuffer) */
155 static volatile int fdc_busy = -1;
156 static volatile int fdc_nested;
157 static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
158 
159 static DECLARE_COMPLETION(motor_on_completion);
160 
161 static volatile int selected = -1;	/* currently selected drive */
162 
163 static int writepending;
164 static int writefromint;
165 static char *raw_buf;
166 static int fdc_queue;
167 
168 static DEFINE_SPINLOCK(amiflop_lock);
169 
170 #define RAW_BUF_SIZE 30000  /* size of raw disk data */
171 
172 /*
173  * These are global variables, as that's the easiest way to give
174  * information to interrupts. They are the data used for the current
175  * request.
176  */
177 static volatile char block_flag;
178 static DECLARE_WAIT_QUEUE_HEAD(wait_fd_block);
179 
180 /* MS-Dos MFM Coding tables (should go quick and easy) */
181 static unsigned char mfmencode[16]={
182 	0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15,
183 	0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55
184 };
185 static unsigned char mfmdecode[128];
186 
187 /* floppy internal millisecond timer stuff */
188 static DECLARE_COMPLETION(ms_wait_completion);
189 #define MS_TICKS ((amiga_eclock+50)/1000)
190 
191 /*
192  * Note that MAX_ERRORS=X doesn't imply that we retry every bad read
193  * max X times - some types of errors increase the errorcount by 2 or
194  * even 3, so we might actually retry only X/2 times before giving up.
195  */
196 #define MAX_ERRORS 12
197 
198 #define custom amiga_custom
199 
200 /* Prevent "aliased" accesses. */
201 static int fd_ref[4] = { 0,0,0,0 };
202 static int fd_device[4] = { 0, 0, 0, 0 };
203 
204 /*
205  * Here come the actual hardware access and helper functions.
206  * They are not reentrant and single threaded because all drives
207  * share the same hardware and the same trackbuffer.
208  */
209 
210 /* Milliseconds timer */
211 
212 static irqreturn_t ms_isr(int irq, void *dummy)
213 {
214 	complete(&ms_wait_completion);
215 	return IRQ_HANDLED;
216 }
217 
218 /* all waits are queued up
219    A more generic routine would do a schedule a la timer.device */
220 static void ms_delay(int ms)
221 {
222 	int ticks;
223 	static DEFINE_MUTEX(mutex);
224 
225 	if (ms > 0) {
226 		mutex_lock(&mutex);
227 		ticks = MS_TICKS*ms-1;
228 		ciaa.tblo=ticks%256;
229 		ciaa.tbhi=ticks/256;
230 		ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
231 		wait_for_completion(&ms_wait_completion);
232 		mutex_unlock(&mutex);
233 	}
234 }
235 
236 /* Hardware semaphore */
237 
238 /* returns true when we would get the semaphore */
239 static inline int try_fdc(int drive)
240 {
241 	drive &= 3;
242 	return ((fdc_busy < 0) || (fdc_busy == drive));
243 }
244 
245 static void get_fdc(int drive)
246 {
247 	unsigned long flags;
248 
249 	drive &= 3;
250 #ifdef DEBUG
251 	printk("get_fdc: drive %d  fdc_busy %d  fdc_nested %d\n",drive,fdc_busy,fdc_nested);
252 #endif
253 	local_irq_save(flags);
254 	wait_event(fdc_wait, try_fdc(drive));
255 	fdc_busy = drive;
256 	fdc_nested++;
257 	local_irq_restore(flags);
258 }
259 
260 static inline void rel_fdc(void)
261 {
262 #ifdef DEBUG
263 	if (fdc_nested == 0)
264 		printk("fd: unmatched rel_fdc\n");
265 	printk("rel_fdc: fdc_busy %d fdc_nested %d\n",fdc_busy,fdc_nested);
266 #endif
267 	fdc_nested--;
268 	if (fdc_nested == 0) {
269 		fdc_busy = -1;
270 		wake_up(&fdc_wait);
271 	}
272 }
273 
274 static void fd_select (int drive)
275 {
276 	unsigned char prb = ~0;
277 
278 	drive&=3;
279 #ifdef DEBUG
280 	printk("selecting %d\n",drive);
281 #endif
282 	if (drive == selected)
283 		return;
284 	get_fdc(drive);
285 	selected = drive;
286 
287 	if (unit[drive].track % 2 != 0)
288 		prb &= ~DSKSIDE;
289 	if (unit[drive].motor == 1)
290 		prb &= ~DSKMOTOR;
291 	ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
292 	ciab.prb = prb;
293 	prb &= ~SELMASK(drive);
294 	ciab.prb = prb;
295 	rel_fdc();
296 }
297 
298 static void fd_deselect (int drive)
299 {
300 	unsigned char prb;
301 	unsigned long flags;
302 
303 	drive&=3;
304 #ifdef DEBUG
305 	printk("deselecting %d\n",drive);
306 #endif
307 	if (drive != selected) {
308 		printk(KERN_WARNING "Deselecting drive %d while %d was selected!\n",drive,selected);
309 		return;
310 	}
311 
312 	get_fdc(drive);
313 	local_irq_save(flags);
314 
315 	selected = -1;
316 
317 	prb = ciab.prb;
318 	prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
319 	ciab.prb = prb;
320 
321 	local_irq_restore (flags);
322 	rel_fdc();
323 
324 }
325 
326 static void motor_on_callback(unsigned long nr)
327 {
328 	if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
329 		complete_all(&motor_on_completion);
330 	} else {
331 		motor_on_timer.expires = jiffies + HZ/10;
332 		add_timer(&motor_on_timer);
333 	}
334 }
335 
336 static int fd_motor_on(int nr)
337 {
338 	nr &= 3;
339 
340 	del_timer(motor_off_timer + nr);
341 
342 	if (!unit[nr].motor) {
343 		unit[nr].motor = 1;
344 		fd_select(nr);
345 
346 		INIT_COMPLETION(motor_on_completion);
347 		motor_on_timer.data = nr;
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 (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(unsigned long drive)
370 {
371 	long calledfromint;
372 #ifdef MODULE
373 	long decusecount;
374 
375 	decusecount = drive & 0x40000000;
376 #endif
377 	calledfromint = drive & 0x80000000;
378 	drive&=3;
379 	if (calledfromint && !try_fdc(drive)) {
380 		/* We would be blocked in an interrupt, so try again later */
381 		motor_off_timer[drive].expires = jiffies + 1;
382 		add_timer(motor_off_timer + drive);
383 		return;
384 	}
385 	unit[drive].motor = 0;
386 	fd_select(drive);
387 	udelay (1);
388 	fd_deselect(drive);
389 }
390 
391 static void floppy_off (unsigned int nr)
392 {
393 	int drive;
394 
395 	drive = nr & 3;
396 	/* called this way it is always from interrupt */
397 	motor_off_timer[drive].data = nr | 0x80000000;
398 	mod_timer(motor_off_timer + drive, jiffies + 3*HZ);
399 }
400 
401 static int fd_calibrate(int drive)
402 {
403 	unsigned char prb;
404 	int n;
405 
406 	drive &= 3;
407 	get_fdc(drive);
408 	if (!fd_motor_on (drive))
409 		return 0;
410 	fd_select (drive);
411 	prb = ciab.prb;
412 	prb |= DSKSIDE;
413 	prb &= ~DSKDIREC;
414 	ciab.prb = prb;
415 	for (n = unit[drive].type->tracks/2; n != 0; --n) {
416 		if (ciaa.pra & DSKTRACK0)
417 			break;
418 		prb &= ~DSKSTEP;
419 		ciab.prb = prb;
420 		prb |= DSKSTEP;
421 		udelay (2);
422 		ciab.prb = prb;
423 		ms_delay(unit[drive].type->step_delay);
424 	}
425 	ms_delay (unit[drive].type->settle_time);
426 	prb |= DSKDIREC;
427 	n = unit[drive].type->tracks + 20;
428 	for (;;) {
429 		prb &= ~DSKSTEP;
430 		ciab.prb = prb;
431 		prb |= DSKSTEP;
432 		udelay (2);
433 		ciab.prb = prb;
434 		ms_delay(unit[drive].type->step_delay + 1);
435 		if ((ciaa.pra & DSKTRACK0) == 0)
436 			break;
437 		if (--n == 0) {
438 			printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);
439 			fd_motor_off (drive);
440 			unit[drive].track = -1;
441 			rel_fdc();
442 			return 0;
443 		}
444 	}
445 	unit[drive].track = 0;
446 	ms_delay(unit[drive].type->settle_time);
447 
448 	rel_fdc();
449 	fd_deselect(drive);
450 	return 1;
451 }
452 
453 static int fd_seek(int drive, int track)
454 {
455 	unsigned char prb;
456 	int cnt;
457 
458 #ifdef DEBUG
459 	printk("seeking drive %d to track %d\n",drive,track);
460 #endif
461 	drive &= 3;
462 	get_fdc(drive);
463 	if (unit[drive].track == track) {
464 		rel_fdc();
465 		return 1;
466 	}
467 	if (!fd_motor_on(drive)) {
468 		rel_fdc();
469 		return 0;
470 	}
471 	if (unit[drive].track < 0 && !fd_calibrate(drive)) {
472 		rel_fdc();
473 		return 0;
474 	}
475 
476 	fd_select (drive);
477 	cnt = unit[drive].track/2 - track/2;
478 	prb = ciab.prb;
479 	prb |= DSKSIDE | DSKDIREC;
480 	if (track % 2 != 0)
481 		prb &= ~DSKSIDE;
482 	if (cnt < 0) {
483 		cnt = - cnt;
484 		prb &= ~DSKDIREC;
485 	}
486 	ciab.prb = prb;
487 	if (track % 2 != unit[drive].track % 2)
488 		ms_delay (unit[drive].type->side_time);
489 	unit[drive].track = track;
490 	if (cnt == 0) {
491 		rel_fdc();
492 		fd_deselect(drive);
493 		return 1;
494 	}
495 	do {
496 		prb &= ~DSKSTEP;
497 		ciab.prb = prb;
498 		prb |= DSKSTEP;
499 		udelay (1);
500 		ciab.prb = prb;
501 		ms_delay (unit[drive].type->step_delay);
502 	} while (--cnt != 0);
503 	ms_delay (unit[drive].type->settle_time);
504 
505 	rel_fdc();
506 	fd_deselect(drive);
507 	return 1;
508 }
509 
510 static unsigned long fd_get_drive_id(int drive)
511 {
512 	int i;
513 	ulong id = 0;
514 
515   	drive&=3;
516   	get_fdc(drive);
517 	/* set up for ID */
518 	MOTOR_ON;
519 	udelay(2);
520 	SELECT(SELMASK(drive));
521 	udelay(2);
522 	DESELECT(SELMASK(drive));
523 	udelay(2);
524 	MOTOR_OFF;
525 	udelay(2);
526 	SELECT(SELMASK(drive));
527 	udelay(2);
528 	DESELECT(SELMASK(drive));
529 	udelay(2);
530 
531 	/* loop and read disk ID */
532 	for (i=0; i<32; i++) {
533 		SELECT(SELMASK(drive));
534 		udelay(2);
535 
536 		/* read and store value of DSKRDY */
537 		id <<= 1;
538 		id |= (ciaa.pra & DSKRDY) ? 0 : 1;	/* cia regs are low-active! */
539 
540 		DESELECT(SELMASK(drive));
541 	}
542 
543 	rel_fdc();
544 
545         /*
546          * RB: At least A500/A2000's df0: don't identify themselves.
547          * As every (real) Amiga has at least a 3.5" DD drive as df0:
548          * we default to that if df0: doesn't identify as a certain
549          * type.
550          */
551         if(drive == 0 && id == FD_NODRIVE)
552 	{
553                 id = fd_def_df0;
554                 printk(KERN_NOTICE "fd: drive 0 didn't identify, setting default %08lx\n", (ulong)fd_def_df0);
555 	}
556 	/* return the ID value */
557 	return (id);
558 }
559 
560 static irqreturn_t fd_block_done(int irq, void *dummy)
561 {
562 	if (block_flag)
563 		custom.dsklen = 0x4000;
564 
565 	if (block_flag == 2) { /* writing */
566 		writepending = 2;
567 		post_write_timer.expires = jiffies + 1; /* at least 2 ms */
568 		post_write_timer.data = selected;
569 		add_timer(&post_write_timer);
570 	}
571 	else {                /* reading */
572 		block_flag = 0;
573 		wake_up (&wait_fd_block);
574 	}
575 	return IRQ_HANDLED;
576 }
577 
578 static void raw_read(int drive)
579 {
580 	drive&=3;
581 	get_fdc(drive);
582 	wait_event(wait_fd_block, !block_flag);
583 	fd_select(drive);
584 	/* setup adkcon bits correctly */
585 	custom.adkcon = ADK_MSBSYNC;
586 	custom.adkcon = ADK_SETCLR|ADK_WORDSYNC|ADK_FAST;
587 
588 	custom.dsksync = MFM_SYNC;
589 
590 	custom.dsklen = 0;
591 	custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
592 	custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
593 	custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
594 
595 	block_flag = 1;
596 
597 	wait_event(wait_fd_block, !block_flag);
598 
599 	custom.dsklen = 0;
600 	fd_deselect(drive);
601 	rel_fdc();
602 }
603 
604 static int raw_write(int drive)
605 {
606 	ushort adk;
607 
608 	drive&=3;
609 	get_fdc(drive); /* corresponds to rel_fdc() in post_write() */
610 	if ((ciaa.pra & DSKPROT) == 0) {
611 		rel_fdc();
612 		return 0;
613 	}
614 	wait_event(wait_fd_block, !block_flag);
615 	fd_select(drive);
616 	/* clear adkcon bits */
617 	custom.adkcon = ADK_PRECOMP1|ADK_PRECOMP0|ADK_WORDSYNC|ADK_MSBSYNC;
618 	/* set appropriate adkcon bits */
619 	adk = ADK_SETCLR|ADK_FAST;
620 	if ((ulong)unit[drive].track >= unit[drive].type->precomp2)
621 		adk |= ADK_PRECOMP1;
622 	else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)
623 		adk |= ADK_PRECOMP0;
624 	custom.adkcon = adk;
625 
626 	custom.dsklen = DSKLEN_WRITE;
627 	custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
628 	custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
629 	custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
630 
631 	block_flag = 2;
632 	return 1;
633 }
634 
635 /*
636  * to be called at least 2ms after the write has finished but before any
637  * other access to the hardware.
638  */
639 static void post_write (unsigned long drive)
640 {
641 #ifdef DEBUG
642 	printk("post_write for drive %ld\n",drive);
643 #endif
644 	drive &= 3;
645 	custom.dsklen = 0;
646 	block_flag = 0;
647 	writepending = 0;
648 	writefromint = 0;
649 	unit[drive].dirty = 0;
650 	wake_up(&wait_fd_block);
651 	fd_deselect(drive);
652 	rel_fdc(); /* corresponds to get_fdc() in raw_write */
653 }
654 
655 
656 /*
657  * The following functions are to convert the block contents into raw data
658  * written to disk and vice versa.
659  * (Add other formats here ;-))
660  */
661 
662 static unsigned long scan_sync(unsigned long raw, unsigned long end)
663 {
664 	ushort *ptr = (ushort *)raw, *endp = (ushort *)end;
665 
666 	while (ptr < endp && *ptr++ != 0x4489)
667 		;
668 	if (ptr < endp) {
669 		while (*ptr == 0x4489 && ptr < endp)
670 			ptr++;
671 		return (ulong)ptr;
672 	}
673 	return 0;
674 }
675 
676 static inline unsigned long checksum(unsigned long *addr, int len)
677 {
678 	unsigned long csum = 0;
679 
680 	len /= sizeof(*addr);
681 	while (len-- > 0)
682 		csum ^= *addr++;
683 	csum = ((csum>>1) & 0x55555555)  ^  (csum & 0x55555555);
684 
685 	return csum;
686 }
687 
688 static unsigned long decode (unsigned long *data, unsigned long *raw,
689 			     int len)
690 {
691 	ulong *odd, *even;
692 
693 	/* convert length from bytes to longwords */
694 	len >>= 2;
695 	odd = raw;
696 	even = odd + len;
697 
698 	/* prepare return pointer */
699 	raw += len * 2;
700 
701 	do {
702 		*data++ = ((*odd++ & 0x55555555) << 1) | (*even++ & 0x55555555);
703 	} while (--len != 0);
704 
705 	return (ulong)raw;
706 }
707 
708 struct header {
709 	unsigned char magic;
710 	unsigned char track;
711 	unsigned char sect;
712 	unsigned char ord;
713 	unsigned char labels[16];
714 	unsigned long hdrchk;
715 	unsigned long datachk;
716 };
717 
718 static int amiga_read(int drive)
719 {
720 	unsigned long raw;
721 	unsigned long end;
722 	int scnt;
723 	unsigned long csum;
724 	struct header hdr;
725 
726 	drive&=3;
727 	raw = (long) raw_buf;
728 	end = raw + unit[drive].type->read_size;
729 
730 	for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
731 		if (!(raw = scan_sync(raw, end))) {
732 			printk (KERN_INFO "can't find sync for sector %d\n", scnt);
733 			return MFM_NOSYNC;
734 		}
735 
736 		raw = decode ((ulong *)&hdr.magic, (ulong *)raw, 4);
737 		raw = decode ((ulong *)&hdr.labels, (ulong *)raw, 16);
738 		raw = decode ((ulong *)&hdr.hdrchk, (ulong *)raw, 4);
739 		raw = decode ((ulong *)&hdr.datachk, (ulong *)raw, 4);
740 		csum = checksum((ulong *)&hdr,
741 				(char *)&hdr.hdrchk-(char *)&hdr);
742 
743 #ifdef DEBUG
744 		printk ("(%x,%d,%d,%d) (%lx,%lx,%lx,%lx) %lx %lx\n",
745 			hdr.magic, hdr.track, hdr.sect, hdr.ord,
746 			*(ulong *)&hdr.labels[0], *(ulong *)&hdr.labels[4],
747 			*(ulong *)&hdr.labels[8], *(ulong *)&hdr.labels[12],
748 			hdr.hdrchk, hdr.datachk);
749 #endif
750 
751 		if (hdr.hdrchk != csum) {
752 			printk(KERN_INFO "MFM_HEADER: %08lx,%08lx\n", hdr.hdrchk, csum);
753 			return MFM_HEADER;
754 		}
755 
756 		/* verify track */
757 		if (hdr.track != unit[drive].track) {
758 			printk(KERN_INFO "MFM_TRACK: %d, %d\n", hdr.track, unit[drive].track);
759 			return MFM_TRACK;
760 		}
761 
762 		raw = decode ((ulong *)(unit[drive].trackbuf + hdr.sect*512),
763 			      (ulong *)raw, 512);
764 		csum = checksum((ulong *)(unit[drive].trackbuf + hdr.sect*512), 512);
765 
766 		if (hdr.datachk != csum) {
767 			printk(KERN_INFO "MFM_DATA: (%x:%d:%d:%d) sc=%d %lx, %lx\n",
768 			       hdr.magic, hdr.track, hdr.sect, hdr.ord, scnt,
769 			       hdr.datachk, csum);
770 			printk (KERN_INFO "data=(%lx,%lx,%lx,%lx)\n",
771 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[0],
772 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[1],
773 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[2],
774 				((ulong *)(unit[drive].trackbuf+hdr.sect*512))[3]);
775 			return MFM_DATA;
776 		}
777 	}
778 
779 	return 0;
780 }
781 
782 static void encode(unsigned long data, unsigned long *dest)
783 {
784 	unsigned long data2;
785 
786 	data &= 0x55555555;
787 	data2 = data ^ 0x55555555;
788 	data |= ((data2 >> 1) | 0x80000000) & (data2 << 1);
789 
790 	if (*(dest - 1) & 0x00000001)
791 		data &= 0x7FFFFFFF;
792 
793 	*dest = data;
794 }
795 
796 static void encode_block(unsigned long *dest, unsigned long *src, int len)
797 {
798 	int cnt, to_cnt = 0;
799 	unsigned long data;
800 
801 	/* odd bits */
802 	for (cnt = 0; cnt < len / 4; cnt++) {
803 		data = src[cnt] >> 1;
804 		encode(data, dest + to_cnt++);
805 	}
806 
807 	/* even bits */
808 	for (cnt = 0; cnt < len / 4; cnt++) {
809 		data = src[cnt];
810 		encode(data, dest + to_cnt++);
811 	}
812 }
813 
814 static unsigned long *putsec(int disk, unsigned long *raw, int cnt)
815 {
816 	struct header hdr;
817 	int i;
818 
819 	disk&=3;
820 	*raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;
821 	raw++;
822 	*raw++ = 0x44894489;
823 
824 	hdr.magic = 0xFF;
825 	hdr.track = unit[disk].track;
826 	hdr.sect = cnt;
827 	hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;
828 	for (i = 0; i < 16; i++)
829 		hdr.labels[i] = 0;
830 	hdr.hdrchk = checksum((ulong *)&hdr,
831 			      (char *)&hdr.hdrchk-(char *)&hdr);
832 	hdr.datachk = checksum((ulong *)(unit[disk].trackbuf+cnt*512), 512);
833 
834 	encode_block(raw, (ulong *)&hdr.magic, 4);
835 	raw += 2;
836 	encode_block(raw, (ulong *)&hdr.labels, 16);
837 	raw += 8;
838 	encode_block(raw, (ulong *)&hdr.hdrchk, 4);
839 	raw += 2;
840 	encode_block(raw, (ulong *)&hdr.datachk, 4);
841 	raw += 2;
842 	encode_block(raw, (ulong *)(unit[disk].trackbuf+cnt*512), 512);
843 	raw += 256;
844 
845 	return raw;
846 }
847 
848 static void amiga_write(int disk)
849 {
850 	unsigned int cnt;
851 	unsigned long *ptr = (unsigned long *)raw_buf;
852 
853 	disk&=3;
854 	/* gap space */
855 	for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)
856 		*ptr++ = 0xaaaaaaaa;
857 
858 	/* sectors */
859 	for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
860 		ptr = putsec (disk, ptr, cnt);
861 	*(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;
862 }
863 
864 
865 struct dos_header {
866 	unsigned char track,   /* 0-80 */
867 		side,    /* 0-1 */
868 		sec,     /* 0-...*/
869 		len_desc;/* 2 */
870 	unsigned short crc;     /* on 68000 we got an alignment problem,
871 				   but this compiler solves it  by adding silently
872 				   adding a pad byte so data won't fit
873 				   and this took about 3h to discover.... */
874 	unsigned char gap1[22];     /* for longword-alignedness (0x4e) */
875 };
876 
877 /* crc routines are borrowed from the messydos-handler  */
878 
879 /* excerpt from the messydos-device
880 ; The CRC is computed not only over the actual data, but including
881 ; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
882 ; As we don't read or encode these fields into our buffers, we have to
883 ; preload the registers containing the CRC with the values they would have
884 ; after stepping over these fields.
885 ;
886 ; How CRCs "really" work:
887 ;
888 ; First, you should regard a bitstring as a series of coefficients of
889 ; polynomials. We calculate with these polynomials in modulo-2
890 ; arithmetic, in which both add and subtract are done the same as
891 ; exclusive-or. Now, we modify our data (a very long polynomial) in
892 ; such a way that it becomes divisible by the CCITT-standard 16-bit
893 ;		 16   12   5
894 ; polynomial:	x  + x	+ x + 1, represented by $11021. The easiest
895 ; way to do this would be to multiply (using proper arithmetic) our
896 ; datablock with $11021. So we have:
897 ;   data * $11021		 =
898 ;   data * ($10000 + $1021)      =
899 ;   data * $10000 + data * $1021
900 ; The left part of this is simple: Just add two 0 bytes. But then
901 ; the right part (data $1021) remains difficult and even could have
902 ; a carry into the left part. The solution is to use a modified
903 ; multiplication, which has a result that is not correct, but with
904 ; a difference of any multiple of $11021. We then only need to keep
905 ; the 16 least significant bits of the result.
906 ;
907 ; The following algorithm does this for us:
908 ;
909 ;   unsigned char *data, c, crclo, crchi;
910 ;   while (not done) {
911 ;	c = *data++ + crchi;
912 ;	crchi = (@ c) >> 8 + crclo;
913 ;	crclo = @ c;
914 ;   }
915 ;
916 ; Remember, + is done with EOR, the @ operator is in two tables (high
917 ; and low byte separately), which is calculated as
918 ;
919 ;      $1021 * (c & $F0)
920 ;  xor $1021 * (c & $0F)
921 ;  xor $1021 * (c >> 4)         (* is regular multiplication)
922 ;
923 ;
924 ; Anyway, the end result is the same as the remainder of the division of
925 ; the data by $11021. I am afraid I need to study theory a bit more...
926 
927 
928 my only works was to code this from manx to C....
929 
930 */
931 
932 static ushort dos_crc(void * data_a3, int data_d0, int data_d1, int data_d3)
933 {
934 	static unsigned char CRCTable1[] = {
935 		0x00,0x10,0x20,0x30,0x40,0x50,0x60,0x70,0x81,0x91,0xa1,0xb1,0xc1,0xd1,0xe1,0xf1,
936 		0x12,0x02,0x32,0x22,0x52,0x42,0x72,0x62,0x93,0x83,0xb3,0xa3,0xd3,0xc3,0xf3,0xe3,
937 		0x24,0x34,0x04,0x14,0x64,0x74,0x44,0x54,0xa5,0xb5,0x85,0x95,0xe5,0xf5,0xc5,0xd5,
938 		0x36,0x26,0x16,0x06,0x76,0x66,0x56,0x46,0xb7,0xa7,0x97,0x87,0xf7,0xe7,0xd7,0xc7,
939 		0x48,0x58,0x68,0x78,0x08,0x18,0x28,0x38,0xc9,0xd9,0xe9,0xf9,0x89,0x99,0xa9,0xb9,
940 		0x5a,0x4a,0x7a,0x6a,0x1a,0x0a,0x3a,0x2a,0xdb,0xcb,0xfb,0xeb,0x9b,0x8b,0xbb,0xab,
941 		0x6c,0x7c,0x4c,0x5c,0x2c,0x3c,0x0c,0x1c,0xed,0xfd,0xcd,0xdd,0xad,0xbd,0x8d,0x9d,
942 		0x7e,0x6e,0x5e,0x4e,0x3e,0x2e,0x1e,0x0e,0xff,0xef,0xdf,0xcf,0xbf,0xaf,0x9f,0x8f,
943 		0x91,0x81,0xb1,0xa1,0xd1,0xc1,0xf1,0xe1,0x10,0x00,0x30,0x20,0x50,0x40,0x70,0x60,
944 		0x83,0x93,0xa3,0xb3,0xc3,0xd3,0xe3,0xf3,0x02,0x12,0x22,0x32,0x42,0x52,0x62,0x72,
945 		0xb5,0xa5,0x95,0x85,0xf5,0xe5,0xd5,0xc5,0x34,0x24,0x14,0x04,0x74,0x64,0x54,0x44,
946 		0xa7,0xb7,0x87,0x97,0xe7,0xf7,0xc7,0xd7,0x26,0x36,0x06,0x16,0x66,0x76,0x46,0x56,
947 		0xd9,0xc9,0xf9,0xe9,0x99,0x89,0xb9,0xa9,0x58,0x48,0x78,0x68,0x18,0x08,0x38,0x28,
948 		0xcb,0xdb,0xeb,0xfb,0x8b,0x9b,0xab,0xbb,0x4a,0x5a,0x6a,0x7a,0x0a,0x1a,0x2a,0x3a,
949 		0xfd,0xed,0xdd,0xcd,0xbd,0xad,0x9d,0x8d,0x7c,0x6c,0x5c,0x4c,0x3c,0x2c,0x1c,0x0c,
950 		0xef,0xff,0xcf,0xdf,0xaf,0xbf,0x8f,0x9f,0x6e,0x7e,0x4e,0x5e,0x2e,0x3e,0x0e,0x1e
951 	};
952 
953 	static unsigned char CRCTable2[] = {
954 		0x00,0x21,0x42,0x63,0x84,0xa5,0xc6,0xe7,0x08,0x29,0x4a,0x6b,0x8c,0xad,0xce,0xef,
955 		0x31,0x10,0x73,0x52,0xb5,0x94,0xf7,0xd6,0x39,0x18,0x7b,0x5a,0xbd,0x9c,0xff,0xde,
956 		0x62,0x43,0x20,0x01,0xe6,0xc7,0xa4,0x85,0x6a,0x4b,0x28,0x09,0xee,0xcf,0xac,0x8d,
957 		0x53,0x72,0x11,0x30,0xd7,0xf6,0x95,0xb4,0x5b,0x7a,0x19,0x38,0xdf,0xfe,0x9d,0xbc,
958 		0xc4,0xe5,0x86,0xa7,0x40,0x61,0x02,0x23,0xcc,0xed,0x8e,0xaf,0x48,0x69,0x0a,0x2b,
959 		0xf5,0xd4,0xb7,0x96,0x71,0x50,0x33,0x12,0xfd,0xdc,0xbf,0x9e,0x79,0x58,0x3b,0x1a,
960 		0xa6,0x87,0xe4,0xc5,0x22,0x03,0x60,0x41,0xae,0x8f,0xec,0xcd,0x2a,0x0b,0x68,0x49,
961 		0x97,0xb6,0xd5,0xf4,0x13,0x32,0x51,0x70,0x9f,0xbe,0xdd,0xfc,0x1b,0x3a,0x59,0x78,
962 		0x88,0xa9,0xca,0xeb,0x0c,0x2d,0x4e,0x6f,0x80,0xa1,0xc2,0xe3,0x04,0x25,0x46,0x67,
963 		0xb9,0x98,0xfb,0xda,0x3d,0x1c,0x7f,0x5e,0xb1,0x90,0xf3,0xd2,0x35,0x14,0x77,0x56,
964 		0xea,0xcb,0xa8,0x89,0x6e,0x4f,0x2c,0x0d,0xe2,0xc3,0xa0,0x81,0x66,0x47,0x24,0x05,
965 		0xdb,0xfa,0x99,0xb8,0x5f,0x7e,0x1d,0x3c,0xd3,0xf2,0x91,0xb0,0x57,0x76,0x15,0x34,
966 		0x4c,0x6d,0x0e,0x2f,0xc8,0xe9,0x8a,0xab,0x44,0x65,0x06,0x27,0xc0,0xe1,0x82,0xa3,
967 		0x7d,0x5c,0x3f,0x1e,0xf9,0xd8,0xbb,0x9a,0x75,0x54,0x37,0x16,0xf1,0xd0,0xb3,0x92,
968 		0x2e,0x0f,0x6c,0x4d,0xaa,0x8b,0xe8,0xc9,0x26,0x07,0x64,0x45,0xa2,0x83,0xe0,0xc1,
969 		0x1f,0x3e,0x5d,0x7c,0x9b,0xba,0xd9,0xf8,0x17,0x36,0x55,0x74,0x93,0xb2,0xd1,0xf0
970 	};
971 
972 /* look at the asm-code - what looks in C a bit strange is almost as good as handmade */
973 	register int i;
974 	register unsigned char *CRCT1, *CRCT2, *data, c, crch, crcl;
975 
976 	CRCT1=CRCTable1;
977 	CRCT2=CRCTable2;
978 	data=data_a3;
979 	crcl=data_d1;
980 	crch=data_d0;
981 	for (i=data_d3; i>=0; i--) {
982 		c = (*data++) ^ crch;
983 		crch = CRCT1[c] ^ crcl;
984 		crcl = CRCT2[c];
985 	}
986 	return (crch<<8)|crcl;
987 }
988 
989 static inline ushort dos_hdr_crc (struct dos_header *hdr)
990 {
991 	return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */
992 }
993 
994 static inline ushort dos_data_crc(unsigned char *data)
995 {
996 	return dos_crc(data, 0xe2, 0x95 ,511); /* precomputed magic */
997 }
998 
999 static inline unsigned char dos_decode_byte(ushort word)
1000 {
1001 	register ushort w2;
1002 	register unsigned char byte;
1003 	register unsigned char *dec = mfmdecode;
1004 
1005 	w2=word;
1006 	w2>>=8;
1007 	w2&=127;
1008 	byte = dec[w2];
1009 	byte <<= 4;
1010 	w2 = word & 127;
1011 	byte |= dec[w2];
1012 	return byte;
1013 }
1014 
1015 static unsigned long dos_decode(unsigned char *data, unsigned short *raw, int len)
1016 {
1017 	int i;
1018 
1019 	for (i = 0; i < len; i++)
1020 		*data++=dos_decode_byte(*raw++);
1021 	return ((ulong)raw);
1022 }
1023 
1024 #ifdef DEBUG
1025 static void dbg(unsigned long ptr)
1026 {
1027 	printk("raw data @%08lx: %08lx, %08lx ,%08lx, %08lx\n", ptr,
1028 	       ((ulong *)ptr)[0], ((ulong *)ptr)[1],
1029 	       ((ulong *)ptr)[2], ((ulong *)ptr)[3]);
1030 }
1031 #endif
1032 
1033 static int dos_read(int drive)
1034 {
1035 	unsigned long end;
1036 	unsigned long raw;
1037 	int scnt;
1038 	unsigned short crc,data_crc[2];
1039 	struct dos_header hdr;
1040 
1041 	drive&=3;
1042 	raw = (long) raw_buf;
1043 	end = raw + unit[drive].type->read_size;
1044 
1045 	for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
1046 		do { /* search for the right sync of each sec-hdr */
1047 			if (!(raw = scan_sync (raw, end))) {
1048 				printk(KERN_INFO "dos_read: no hdr sync on "
1049 				       "track %d, unit %d for sector %d\n",
1050 				       unit[drive].track,drive,scnt);
1051 				return MFM_NOSYNC;
1052 			}
1053 #ifdef DEBUG
1054 			dbg(raw);
1055 #endif
1056 		} while (*((ushort *)raw)!=0x5554); /* loop usually only once done */
1057 		raw+=2; /* skip over headermark */
1058 		raw = dos_decode((unsigned char *)&hdr,(ushort *) raw,8);
1059 		crc = dos_hdr_crc(&hdr);
1060 
1061 #ifdef DEBUG
1062 		printk("(%3d,%d,%2d,%d) %x\n", hdr.track, hdr.side,
1063 		       hdr.sec, hdr.len_desc, hdr.crc);
1064 #endif
1065 
1066 		if (crc != hdr.crc) {
1067 			printk(KERN_INFO "dos_read: MFM_HEADER %04x,%04x\n",
1068 			       hdr.crc, crc);
1069 			return MFM_HEADER;
1070 		}
1071 		if (hdr.track != unit[drive].track/unit[drive].type->heads) {
1072 			printk(KERN_INFO "dos_read: MFM_TRACK %d, %d\n",
1073 			       hdr.track,
1074 			       unit[drive].track/unit[drive].type->heads);
1075 			return MFM_TRACK;
1076 		}
1077 
1078 		if (hdr.side != unit[drive].track%unit[drive].type->heads) {
1079 			printk(KERN_INFO "dos_read: MFM_SIDE %d, %d\n",
1080 			       hdr.side,
1081 			       unit[drive].track%unit[drive].type->heads);
1082 			return MFM_TRACK;
1083 		}
1084 
1085 		if (hdr.len_desc != 2) {
1086 			printk(KERN_INFO "dos_read: unknown sector len "
1087 			       "descriptor %d\n", hdr.len_desc);
1088 			return MFM_DATA;
1089 		}
1090 #ifdef DEBUG
1091 		printk("hdr accepted\n");
1092 #endif
1093 		if (!(raw = scan_sync (raw, end))) {
1094 			printk(KERN_INFO "dos_read: no data sync on track "
1095 			       "%d, unit %d for sector%d, disk sector %d\n",
1096 			       unit[drive].track, drive, scnt, hdr.sec);
1097 			return MFM_NOSYNC;
1098 		}
1099 #ifdef DEBUG
1100 		dbg(raw);
1101 #endif
1102 
1103 		if (*((ushort *)raw)!=0x5545) {
1104 			printk(KERN_INFO "dos_read: no data mark after "
1105 			       "sync (%d,%d,%d,%d) sc=%d\n",
1106 			       hdr.track,hdr.side,hdr.sec,hdr.len_desc,scnt);
1107 			return MFM_NOSYNC;
1108 		}
1109 
1110 		raw+=2;  /* skip data mark (included in checksum) */
1111 		raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 512);
1112 		raw = dos_decode((unsigned char  *)data_crc,(ushort *) raw,4);
1113 		crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);
1114 
1115 		if (crc != data_crc[0]) {
1116 			printk(KERN_INFO "dos_read: MFM_DATA (%d,%d,%d,%d) "
1117 			       "sc=%d, %x %x\n", hdr.track, hdr.side,
1118 			       hdr.sec, hdr.len_desc, scnt,data_crc[0], crc);
1119 			printk(KERN_INFO "data=(%lx,%lx,%lx,%lx,...)\n",
1120 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],
1121 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],
1122 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],
1123 			       ((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);
1124 			return MFM_DATA;
1125 		}
1126 	}
1127 	return 0;
1128 }
1129 
1130 static inline ushort dos_encode_byte(unsigned char byte)
1131 {
1132 	register unsigned char *enc, b2, b1;
1133 	register ushort word;
1134 
1135 	enc=mfmencode;
1136 	b1=byte;
1137 	b2=b1>>4;
1138 	b1&=15;
1139 	word=enc[b2] <<8 | enc [b1];
1140 	return (word|((word&(256|64)) ? 0: 128));
1141 }
1142 
1143 static void dos_encode_block(ushort *dest, unsigned char *src, int len)
1144 {
1145 	int i;
1146 
1147 	for (i = 0; i < len; i++) {
1148 		*dest=dos_encode_byte(*src++);
1149 		*dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;
1150 		dest++;
1151 	}
1152 }
1153 
1154 static unsigned long *ms_putsec(int drive, unsigned long *raw, int cnt)
1155 {
1156 	static struct dos_header hdr={0,0,0,2,0,
1157 	  {78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78}};
1158 	int i;
1159 	static ushort crc[2]={0,0x4e4e};
1160 
1161 	drive&=3;
1162 /* id gap 1 */
1163 /* the MFM word before is always 9254 */
1164 	for(i=0;i<6;i++)
1165 		*raw++=0xaaaaaaaa;
1166 /* 3 sync + 1 headermark */
1167 	*raw++=0x44894489;
1168 	*raw++=0x44895554;
1169 
1170 /* fill in the variable parts of the header */
1171 	hdr.track=unit[drive].track/unit[drive].type->heads;
1172 	hdr.side=unit[drive].track%unit[drive].type->heads;
1173 	hdr.sec=cnt+1;
1174 	hdr.crc=dos_hdr_crc(&hdr);
1175 
1176 /* header (without "magic") and id gap 2*/
1177 	dos_encode_block((ushort *)raw,(unsigned char *) &hdr.track,28);
1178 	raw+=14;
1179 
1180 /*id gap 3 */
1181 	for(i=0;i<6;i++)
1182 		*raw++=0xaaaaaaaa;
1183 
1184 /* 3 syncs and 1 datamark */
1185 	*raw++=0x44894489;
1186 	*raw++=0x44895545;
1187 
1188 /* data */
1189 	dos_encode_block((ushort *)raw,
1190 			 (unsigned char *)unit[drive].trackbuf+cnt*512,512);
1191 	raw+=256;
1192 
1193 /*data crc + jd's special gap (long words :-/) */
1194 	crc[0]=dos_data_crc(unit[drive].trackbuf+cnt*512);
1195 	dos_encode_block((ushort *) raw,(unsigned char *)crc,4);
1196 	raw+=2;
1197 
1198 /* data gap */
1199 	for(i=0;i<38;i++)
1200 		*raw++=0x92549254;
1201 
1202 	return raw; /* wrote 652 MFM words */
1203 }
1204 
1205 static void dos_write(int disk)
1206 {
1207 	int cnt;
1208 	unsigned long raw = (unsigned long) raw_buf;
1209 	unsigned long *ptr=(unsigned long *)raw;
1210 
1211 	disk&=3;
1212 /* really gap4 + indexgap , but we write it first and round it up */
1213 	for (cnt=0;cnt<425;cnt++)
1214 		*ptr++=0x92549254;
1215 
1216 /* the following is just guessed */
1217 	if (unit[disk].type->sect_mult==2)  /* check for HD-Disks */
1218 		for(cnt=0;cnt<473;cnt++)
1219 			*ptr++=0x92549254;
1220 
1221 /* now the index marks...*/
1222 	for (cnt=0;cnt<20;cnt++)
1223 		*ptr++=0x92549254;
1224 	for (cnt=0;cnt<6;cnt++)
1225 		*ptr++=0xaaaaaaaa;
1226 	*ptr++=0x52245224;
1227 	*ptr++=0x52245552;
1228 	for (cnt=0;cnt<20;cnt++)
1229 		*ptr++=0x92549254;
1230 
1231 /* sectors */
1232 	for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
1233 		ptr=ms_putsec(disk,ptr,cnt);
1234 
1235 	*(ushort *)ptr = 0xaaa8; /* MFM word before is always 0x9254 */
1236 }
1237 
1238 /*
1239  * Here comes the high level stuff (i.e. the filesystem interface)
1240  * and helper functions.
1241  * Normally this should be the only part that has to be adapted to
1242  * different kernel versions.
1243  */
1244 
1245 /* FIXME: this assumes the drive is still spinning -
1246  * which is only true if we complete writing a track within three seconds
1247  */
1248 static void flush_track_callback(unsigned long nr)
1249 {
1250 	nr&=3;
1251 	writefromint = 1;
1252 	if (!try_fdc(nr)) {
1253 		/* we might block in an interrupt, so try again later */
1254 		flush_track_timer[nr].expires = jiffies + 1;
1255 		add_timer(flush_track_timer + nr);
1256 		return;
1257 	}
1258 	get_fdc(nr);
1259 	(*unit[nr].dtype->write_fkt)(nr);
1260 	if (!raw_write(nr)) {
1261 		printk (KERN_NOTICE "floppy disk write protected\n");
1262 		writefromint = 0;
1263 		writepending = 0;
1264 	}
1265 	rel_fdc();
1266 }
1267 
1268 static int non_int_flush_track (unsigned long nr)
1269 {
1270 	unsigned long flags;
1271 
1272 	nr&=3;
1273 	writefromint = 0;
1274 	del_timer(&post_write_timer);
1275 	get_fdc(nr);
1276 	if (!fd_motor_on(nr)) {
1277 		writepending = 0;
1278 		rel_fdc();
1279 		return 0;
1280 	}
1281 	local_irq_save(flags);
1282 	if (writepending != 2) {
1283 		local_irq_restore(flags);
1284 		(*unit[nr].dtype->write_fkt)(nr);
1285 		if (!raw_write(nr)) {
1286 			printk (KERN_NOTICE "floppy disk write protected "
1287 				"in write!\n");
1288 			writepending = 0;
1289 			return 0;
1290 		}
1291 		wait_event(wait_fd_block, block_flag != 2);
1292 	}
1293 	else {
1294 		local_irq_restore(flags);
1295 		ms_delay(2); /* 2 ms post_write delay */
1296 		post_write(nr);
1297 	}
1298 	rel_fdc();
1299 	return 1;
1300 }
1301 
1302 static int get_track(int drive, int track)
1303 {
1304 	int error, errcnt;
1305 
1306 	drive&=3;
1307 	if (unit[drive].track == track)
1308 		return 0;
1309 	get_fdc(drive);
1310 	if (!fd_motor_on(drive)) {
1311 		rel_fdc();
1312 		return -1;
1313 	}
1314 
1315 	if (unit[drive].dirty == 1) {
1316 		del_timer (flush_track_timer + drive);
1317 		non_int_flush_track (drive);
1318 	}
1319 	errcnt = 0;
1320 	while (errcnt < MAX_ERRORS) {
1321 		if (!fd_seek(drive, track))
1322 			return -1;
1323 		raw_read(drive);
1324 		error = (*unit[drive].dtype->read_fkt)(drive);
1325 		if (error == 0) {
1326 			rel_fdc();
1327 			return 0;
1328 		}
1329 		/* Read Error Handling: recalibrate and try again */
1330 		unit[drive].track = -1;
1331 		errcnt++;
1332 	}
1333 	rel_fdc();
1334 	return -1;
1335 }
1336 
1337 /*
1338  * Round-robin between our available drives, doing one request from each
1339  */
1340 static struct request *set_next_request(void)
1341 {
1342 	struct request_queue *q;
1343 	int cnt = FD_MAX_UNITS;
1344 	struct request *rq = NULL;
1345 
1346 	/* Find next queue we can dispatch from */
1347 	fdc_queue = fdc_queue + 1;
1348 	if (fdc_queue == FD_MAX_UNITS)
1349 		fdc_queue = 0;
1350 
1351 	for(cnt = FD_MAX_UNITS; cnt > 0; cnt--) {
1352 
1353 		if (unit[fdc_queue].type->code == FD_NODRIVE) {
1354 			if (++fdc_queue == FD_MAX_UNITS)
1355 				fdc_queue = 0;
1356 			continue;
1357 		}
1358 
1359 		q = unit[fdc_queue].gendisk->queue;
1360 		if (q) {
1361 			rq = blk_fetch_request(q);
1362 			if (rq)
1363 				break;
1364 		}
1365 
1366 		if (++fdc_queue == FD_MAX_UNITS)
1367 			fdc_queue = 0;
1368 	}
1369 
1370 	return rq;
1371 }
1372 
1373 static void redo_fd_request(void)
1374 {
1375 	struct request *rq;
1376 	unsigned int cnt, block, track, sector;
1377 	int drive;
1378 	struct amiga_floppy_struct *floppy;
1379 	char *data;
1380 	unsigned long flags;
1381 	int err;
1382 
1383 next_req:
1384 	rq = set_next_request();
1385 	if (!rq) {
1386 		/* Nothing left to do */
1387 		return;
1388 	}
1389 
1390 	floppy = rq->rq_disk->private_data;
1391 	drive = floppy - unit;
1392 
1393 next_segment:
1394 	/* Here someone could investigate to be more efficient */
1395 	for (cnt = 0, err = 0; cnt < blk_rq_cur_sectors(rq); cnt++) {
1396 #ifdef DEBUG
1397 		printk("fd: sector %ld + %d requested for %s\n",
1398 		       blk_rq_pos(rq), cnt,
1399 		       (rq_data_dir(rq) == READ) ? "read" : "write");
1400 #endif
1401 		block = blk_rq_pos(rq) + cnt;
1402 		if ((int)block > floppy->blocks) {
1403 			err = -EIO;
1404 			break;
1405 		}
1406 
1407 		track = block / (floppy->dtype->sects * floppy->type->sect_mult);
1408 		sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
1409 		data = rq->buffer + 512 * cnt;
1410 #ifdef DEBUG
1411 		printk("access to track %d, sector %d, with buffer at "
1412 		       "0x%08lx\n", track, sector, data);
1413 #endif
1414 
1415 		if (get_track(drive, track) == -1) {
1416 			err = -EIO;
1417 			break;
1418 		}
1419 
1420 		if (rq_data_dir(rq) == READ) {
1421 			memcpy(data, floppy->trackbuf + sector * 512, 512);
1422 		} else {
1423 			memcpy(floppy->trackbuf + sector * 512, data, 512);
1424 
1425 			/* keep the drive spinning while writes are scheduled */
1426 			if (!fd_motor_on(drive)) {
1427 				err = -EIO;
1428 				break;
1429 			}
1430 			/*
1431 			 * setup a callback to write the track buffer
1432 			 * after a short (1 tick) delay.
1433 			 */
1434 			local_irq_save(flags);
1435 
1436 			floppy->dirty = 1;
1437 		        /* reset the timer */
1438 			mod_timer (flush_track_timer + drive, jiffies + 1);
1439 			local_irq_restore(flags);
1440 		}
1441 	}
1442 
1443 	if (__blk_end_request_cur(rq, err))
1444 		goto next_segment;
1445 	goto next_req;
1446 }
1447 
1448 static void do_fd_request(struct request_queue * q)
1449 {
1450 	redo_fd_request();
1451 }
1452 
1453 static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1454 {
1455 	int drive = MINOR(bdev->bd_dev) & 3;
1456 
1457 	geo->heads = unit[drive].type->heads;
1458 	geo->sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
1459 	geo->cylinders = unit[drive].type->tracks;
1460 	return 0;
1461 }
1462 
1463 static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
1464 		    unsigned int cmd, unsigned long param)
1465 {
1466 	struct amiga_floppy_struct *p = bdev->bd_disk->private_data;
1467 	int drive = p - unit;
1468 	static struct floppy_struct getprm;
1469 	void __user *argp = (void __user *)param;
1470 
1471 	switch(cmd){
1472 	case FDFMTBEG:
1473 		get_fdc(drive);
1474 		if (fd_ref[drive] > 1) {
1475 			rel_fdc();
1476 			return -EBUSY;
1477 		}
1478 		fsync_bdev(bdev);
1479 		if (fd_motor_on(drive) == 0) {
1480 			rel_fdc();
1481 			return -ENODEV;
1482 		}
1483 		if (fd_calibrate(drive) == 0) {
1484 			rel_fdc();
1485 			return -ENXIO;
1486 		}
1487 		floppy_off(drive);
1488 		rel_fdc();
1489 		break;
1490 	case FDFMTTRK:
1491 		if (param < p->type->tracks * p->type->heads)
1492 		{
1493 			get_fdc(drive);
1494 			if (fd_seek(drive,param) != 0){
1495 				memset(p->trackbuf, FD_FILL_BYTE,
1496 				       p->dtype->sects * p->type->sect_mult * 512);
1497 				non_int_flush_track(drive);
1498 			}
1499 			floppy_off(drive);
1500 			rel_fdc();
1501 		}
1502 		else
1503 			return -EINVAL;
1504 		break;
1505 	case FDFMTEND:
1506 		floppy_off(drive);
1507 		invalidate_bdev(bdev);
1508 		break;
1509 	case FDGETPRM:
1510 		memset((void *)&getprm, 0, sizeof (getprm));
1511 		getprm.track=p->type->tracks;
1512 		getprm.head=p->type->heads;
1513 		getprm.sect=p->dtype->sects * p->type->sect_mult;
1514 		getprm.size=p->blocks;
1515 		if (copy_to_user(argp, &getprm, sizeof(struct floppy_struct)))
1516 			return -EFAULT;
1517 		break;
1518 	case FDSETPRM:
1519 	case FDDEFPRM:
1520 		return -EINVAL;
1521 	case FDFLUSH: /* unconditionally, even if not needed */
1522 		del_timer (flush_track_timer + drive);
1523 		non_int_flush_track(drive);
1524 		break;
1525 #ifdef RAW_IOCTL
1526 	case IOCTL_RAW_TRACK:
1527 		if (copy_to_user(argp, raw_buf, p->type->read_size))
1528 			return -EFAULT;
1529 		else
1530 			return p->type->read_size;
1531 #endif
1532 	default:
1533 		printk(KERN_DEBUG "fd_ioctl: unknown cmd %d for drive %d.",
1534 		       cmd, drive);
1535 		return -ENOSYS;
1536 	}
1537 	return 0;
1538 }
1539 
1540 static int fd_ioctl(struct block_device *bdev, fmode_t mode,
1541 			     unsigned int cmd, unsigned long param)
1542 {
1543 	int ret;
1544 
1545 	mutex_lock(&amiflop_mutex);
1546 	ret = fd_locked_ioctl(bdev, mode, cmd, param);
1547 	mutex_unlock(&amiflop_mutex);
1548 
1549 	return ret;
1550 }
1551 
1552 static void fd_probe(int dev)
1553 {
1554 	unsigned long code;
1555 	int type;
1556 	int drive;
1557 
1558 	drive = dev & 3;
1559 	code = fd_get_drive_id(drive);
1560 
1561 	/* get drive type */
1562 	for (type = 0; type < num_dr_types; type++)
1563 		if (drive_types[type].code == code)
1564 			break;
1565 
1566 	if (type >= num_dr_types) {
1567 		printk(KERN_WARNING "fd_probe: unsupported drive type "
1568 		       "%08lx found\n", code);
1569 		unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */
1570 		return;
1571 	}
1572 
1573 	unit[drive].type = drive_types + type;
1574 	unit[drive].track = -1;
1575 
1576 	unit[drive].disk = -1;
1577 	unit[drive].motor = 0;
1578 	unit[drive].busy = 0;
1579 	unit[drive].status = -1;
1580 }
1581 
1582 /*
1583  * floppy_open check for aliasing (/dev/fd0 can be the same as
1584  * /dev/PS0 etc), and disallows simultaneous access to the same
1585  * drive with different device numbers.
1586  */
1587 static int floppy_open(struct block_device *bdev, fmode_t mode)
1588 {
1589 	int drive = MINOR(bdev->bd_dev) & 3;
1590 	int system =  (MINOR(bdev->bd_dev) & 4) >> 2;
1591 	int old_dev;
1592 	unsigned long flags;
1593 
1594 	mutex_lock(&amiflop_mutex);
1595 	old_dev = fd_device[drive];
1596 
1597 	if (fd_ref[drive] && old_dev != system) {
1598 		mutex_unlock(&amiflop_mutex);
1599 		return -EBUSY;
1600 	}
1601 
1602 	if (mode & (FMODE_READ|FMODE_WRITE)) {
1603 		check_disk_change(bdev);
1604 		if (mode & FMODE_WRITE) {
1605 			int wrprot;
1606 
1607 			get_fdc(drive);
1608 			fd_select (drive);
1609 			wrprot = !(ciaa.pra & DSKPROT);
1610 			fd_deselect (drive);
1611 			rel_fdc();
1612 
1613 			if (wrprot) {
1614 				mutex_unlock(&amiflop_mutex);
1615 				return -EROFS;
1616 			}
1617 		}
1618 	}
1619 
1620 	local_irq_save(flags);
1621 	fd_ref[drive]++;
1622 	fd_device[drive] = system;
1623 	local_irq_restore(flags);
1624 
1625 	unit[drive].dtype=&data_types[system];
1626 	unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
1627 		data_types[system].sects*unit[drive].type->sect_mult;
1628 	set_capacity(unit[drive].gendisk, unit[drive].blocks);
1629 
1630 	printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
1631 	       unit[drive].type->name, data_types[system].name);
1632 
1633 	mutex_unlock(&amiflop_mutex);
1634 	return 0;
1635 }
1636 
1637 static int floppy_release(struct gendisk *disk, fmode_t mode)
1638 {
1639 	struct amiga_floppy_struct *p = disk->private_data;
1640 	int drive = p - unit;
1641 
1642 	mutex_lock(&amiflop_mutex);
1643 	if (unit[drive].dirty == 1) {
1644 		del_timer (flush_track_timer + drive);
1645 		non_int_flush_track (drive);
1646 	}
1647 
1648 	if (!fd_ref[drive]--) {
1649 		printk(KERN_CRIT "floppy_release with fd_ref == 0");
1650 		fd_ref[drive] = 0;
1651 	}
1652 #ifdef MODULE
1653 /* the mod_use counter is handled this way */
1654 	floppy_off (drive | 0x40000000);
1655 #endif
1656 	mutex_unlock(&amiflop_mutex);
1657 	return 0;
1658 }
1659 
1660 /*
1661  * check_events is never called from an interrupt, so we can relax a bit
1662  * here, sleep etc. Note that floppy-on tries to set current_DOR to point
1663  * to the desired drive, but it will probably not survive the sleep if
1664  * several floppies are used at the same time: thus the loop.
1665  */
1666 static unsigned amiga_check_events(struct gendisk *disk, unsigned int clearing)
1667 {
1668 	struct amiga_floppy_struct *p = disk->private_data;
1669 	int drive = p - unit;
1670 	int changed;
1671 	static int first_time = 1;
1672 
1673 	if (first_time)
1674 		changed = first_time--;
1675 	else {
1676 		get_fdc(drive);
1677 		fd_select (drive);
1678 		changed = !(ciaa.pra & DSKCHANGE);
1679 		fd_deselect (drive);
1680 		rel_fdc();
1681 	}
1682 
1683 	if (changed) {
1684 		fd_probe(drive);
1685 		p->track = -1;
1686 		p->dirty = 0;
1687 		writepending = 0; /* if this was true before, too bad! */
1688 		writefromint = 0;
1689 		return DISK_EVENT_MEDIA_CHANGE;
1690 	}
1691 	return 0;
1692 }
1693 
1694 static const struct block_device_operations floppy_fops = {
1695 	.owner		= THIS_MODULE,
1696 	.open		= floppy_open,
1697 	.release	= floppy_release,
1698 	.ioctl		= fd_ioctl,
1699 	.getgeo		= fd_getgeo,
1700 	.check_events	= amiga_check_events,
1701 };
1702 
1703 static int __init fd_probe_drives(void)
1704 {
1705 	int drive,drives,nomem;
1706 
1707 	printk(KERN_INFO "FD: probing units\nfound ");
1708 	drives=0;
1709 	nomem=0;
1710 	for(drive=0;drive<FD_MAX_UNITS;drive++) {
1711 		struct gendisk *disk;
1712 		fd_probe(drive);
1713 		if (unit[drive].type->code == FD_NODRIVE)
1714 			continue;
1715 		disk = alloc_disk(1);
1716 		if (!disk) {
1717 			unit[drive].type->code = FD_NODRIVE;
1718 			continue;
1719 		}
1720 		unit[drive].gendisk = disk;
1721 
1722 		disk->queue = blk_init_queue(do_fd_request, &amiflop_lock);
1723 		if (!disk->queue) {
1724 			unit[drive].type->code = FD_NODRIVE;
1725 			continue;
1726 		}
1727 
1728 		drives++;
1729 		if ((unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL)) == NULL) {
1730 			printk("no mem for ");
1731 			unit[drive].type = &drive_types[num_dr_types - 1]; /* FD_NODRIVE */
1732 			drives--;
1733 			nomem = 1;
1734 		}
1735 		printk("fd%d ",drive);
1736 		disk->major = FLOPPY_MAJOR;
1737 		disk->first_minor = drive;
1738 		disk->fops = &floppy_fops;
1739 		sprintf(disk->disk_name, "fd%d", drive);
1740 		disk->private_data = &unit[drive];
1741 		set_capacity(disk, 880*2);
1742 		add_disk(disk);
1743 	}
1744 	if ((drives > 0) || (nomem == 0)) {
1745 		if (drives == 0)
1746 			printk("no drives");
1747 		printk("\n");
1748 		return drives;
1749 	}
1750 	printk("\n");
1751 	return -ENOMEM;
1752 }
1753 
1754 static struct kobject *floppy_find(dev_t dev, int *part, void *data)
1755 {
1756 	int drive = *part & 3;
1757 	if (unit[drive].type->code == FD_NODRIVE)
1758 		return NULL;
1759 	*part = 0;
1760 	return get_disk(unit[drive].gendisk);
1761 }
1762 
1763 static int __init amiga_floppy_probe(struct platform_device *pdev)
1764 {
1765 	int i, ret;
1766 
1767 	if (register_blkdev(FLOPPY_MAJOR,"fd"))
1768 		return -EBUSY;
1769 
1770 	ret = -ENOMEM;
1771 	raw_buf = amiga_chip_alloc(RAW_BUF_SIZE, "Floppy");
1772 	if (!raw_buf) {
1773 		printk("fd: cannot get chip mem buffer\n");
1774 		goto out_blkdev;
1775 	}
1776 
1777 	ret = -EBUSY;
1778 	if (request_irq(IRQ_AMIGA_DSKBLK, fd_block_done, 0, "floppy_dma", NULL)) {
1779 		printk("fd: cannot get irq for dma\n");
1780 		goto out_irq;
1781 	}
1782 
1783 	if (request_irq(IRQ_AMIGA_CIAA_TB, ms_isr, 0, "floppy_timer", NULL)) {
1784 		printk("fd: cannot get irq for timer\n");
1785 		goto out_irq2;
1786 	}
1787 
1788 	ret = -ENODEV;
1789 	if (fd_probe_drives() < 1) /* No usable drives */
1790 		goto out_probe;
1791 
1792 	blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
1793 				floppy_find, NULL, NULL);
1794 
1795 	/* initialize variables */
1796 	init_timer(&motor_on_timer);
1797 	motor_on_timer.expires = 0;
1798 	motor_on_timer.data = 0;
1799 	motor_on_timer.function = motor_on_callback;
1800 	for (i = 0; i < FD_MAX_UNITS; i++) {
1801 		init_timer(&motor_off_timer[i]);
1802 		motor_off_timer[i].expires = 0;
1803 		motor_off_timer[i].data = i|0x80000000;
1804 		motor_off_timer[i].function = fd_motor_off;
1805 		init_timer(&flush_track_timer[i]);
1806 		flush_track_timer[i].expires = 0;
1807 		flush_track_timer[i].data = i;
1808 		flush_track_timer[i].function = flush_track_callback;
1809 
1810 		unit[i].track = -1;
1811 	}
1812 
1813 	init_timer(&post_write_timer);
1814 	post_write_timer.expires = 0;
1815 	post_write_timer.data = 0;
1816 	post_write_timer.function = post_write;
1817 
1818 	for (i = 0; i < 128; i++)
1819 		mfmdecode[i]=255;
1820 	for (i = 0; i < 16; i++)
1821 		mfmdecode[mfmencode[i]]=i;
1822 
1823 	/* make sure that disk DMA is enabled */
1824 	custom.dmacon = DMAF_SETCLR | DMAF_DISK;
1825 
1826 	/* init ms timer */
1827 	ciaa.crb = 8; /* one-shot, stop */
1828 	return 0;
1829 
1830 out_probe:
1831 	free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1832 out_irq2:
1833 	free_irq(IRQ_AMIGA_DSKBLK, NULL);
1834 out_irq:
1835 	amiga_chip_free(raw_buf);
1836 out_blkdev:
1837 	unregister_blkdev(FLOPPY_MAJOR,"fd");
1838 	return ret;
1839 }
1840 
1841 #if 0 /* not safe to unload */
1842 static int __exit amiga_floppy_remove(struct platform_device *pdev)
1843 {
1844 	int i;
1845 
1846 	for( i = 0; i < FD_MAX_UNITS; i++) {
1847 		if (unit[i].type->code != FD_NODRIVE) {
1848 			struct request_queue *q = unit[i].gendisk->queue;
1849 			del_gendisk(unit[i].gendisk);
1850 			put_disk(unit[i].gendisk);
1851 			kfree(unit[i].trackbuf);
1852 			if (q)
1853 				blk_cleanup_queue(q);
1854 		}
1855 	}
1856 	blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
1857 	free_irq(IRQ_AMIGA_CIAA_TB, NULL);
1858 	free_irq(IRQ_AMIGA_DSKBLK, NULL);
1859 	custom.dmacon = DMAF_DISK; /* disable DMA */
1860 	amiga_chip_free(raw_buf);
1861 	unregister_blkdev(FLOPPY_MAJOR, "fd");
1862 }
1863 #endif
1864 
1865 static struct platform_driver amiga_floppy_driver = {
1866 	.driver   = {
1867 		.name	= "amiga-floppy",
1868 		.owner	= THIS_MODULE,
1869 	},
1870 };
1871 
1872 static int __init amiga_floppy_init(void)
1873 {
1874 	return platform_driver_probe(&amiga_floppy_driver, amiga_floppy_probe);
1875 }
1876 
1877 module_init(amiga_floppy_init);
1878 
1879 #ifndef MODULE
1880 static int __init amiga_floppy_setup (char *str)
1881 {
1882 	int n;
1883 	if (!MACH_IS_AMIGA)
1884 		return 0;
1885 	if (!get_option(&str, &n))
1886 		return 0;
1887 	printk (KERN_INFO "amiflop: Setting default df0 to %x\n", n);
1888 	fd_def_df0 = n;
1889 	return 1;
1890 }
1891 
1892 __setup("floppy=", amiga_floppy_setup);
1893 #endif
1894 
1895 MODULE_ALIAS("platform:amiga-floppy");
1896