xref: /openbmc/linux/drivers/block/swim.c (revision ced7c287)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for SWIM (Sander Woz Integrated Machine) floppy controller
4  *
5  * Copyright (C) 2004,2008 Laurent Vivier <Laurent@lvivier.info>
6  *
7  * based on Alastair Bridgewater SWIM analysis, 2001
8  * based on SWIM3 driver (c) Paul Mackerras, 1996
9  * based on netBSD IWM driver (c) 1997, 1998 Hauke Fath.
10  *
11  * 2004-08-21 (lv) - Initial implementation
12  * 2008-10-30 (lv) - Port to 2.6
13  */
14 
15 #include <linux/module.h>
16 #include <linux/fd.h>
17 #include <linux/slab.h>
18 #include <linux/blk-mq.h>
19 #include <linux/mutex.h>
20 #include <linux/hdreg.h>
21 #include <linux/kernel.h>
22 #include <linux/delay.h>
23 #include <linux/platform_device.h>
24 
25 #include <asm/mac_via.h>
26 
27 #define CARDNAME "swim"
28 
29 struct sector_header {
30 	unsigned char side;
31 	unsigned char track;
32 	unsigned char sector;
33 	unsigned char size;
34 	unsigned char crc0;
35 	unsigned char crc1;
36 } __attribute__((packed));
37 
38 #define DRIVER_VERSION "Version 0.2 (2008-10-30)"
39 
40 #define REG(x)	unsigned char x, x ## _pad[0x200 - 1];
41 
42 struct swim {
43 	REG(write_data)
44 	REG(write_mark)
45 	REG(write_CRC)
46 	REG(write_parameter)
47 	REG(write_phase)
48 	REG(write_setup)
49 	REG(write_mode0)
50 	REG(write_mode1)
51 
52 	REG(read_data)
53 	REG(read_mark)
54 	REG(read_error)
55 	REG(read_parameter)
56 	REG(read_phase)
57 	REG(read_setup)
58 	REG(read_status)
59 	REG(read_handshake)
60 } __attribute__((packed));
61 
62 #define swim_write(base, reg, v) 	out_8(&(base)->write_##reg, (v))
63 #define swim_read(base, reg)		in_8(&(base)->read_##reg)
64 
65 /* IWM registers */
66 
67 struct iwm {
68 	REG(ph0L)
69 	REG(ph0H)
70 	REG(ph1L)
71 	REG(ph1H)
72 	REG(ph2L)
73 	REG(ph2H)
74 	REG(ph3L)
75 	REG(ph3H)
76 	REG(mtrOff)
77 	REG(mtrOn)
78 	REG(intDrive)
79 	REG(extDrive)
80 	REG(q6L)
81 	REG(q6H)
82 	REG(q7L)
83 	REG(q7H)
84 } __attribute__((packed));
85 
86 #define iwm_write(base, reg, v) 	out_8(&(base)->reg, (v))
87 #define iwm_read(base, reg)		in_8(&(base)->reg)
88 
89 /* bits in phase register */
90 
91 #define SEEK_POSITIVE	0x070
92 #define SEEK_NEGATIVE	0x074
93 #define STEP		0x071
94 #define MOTOR_ON	0x072
95 #define MOTOR_OFF	0x076
96 #define INDEX		0x073
97 #define EJECT		0x077
98 #define SETMFM		0x171
99 #define SETGCR		0x175
100 
101 #define RELAX		0x033
102 #define LSTRB		0x008
103 
104 #define CA_MASK		0x077
105 
106 /* Select values for swim_select and swim_readbit */
107 
108 #define READ_DATA_0	0x074
109 #define ONEMEG_DRIVE	0x075
110 #define SINGLE_SIDED	0x076
111 #define DRIVE_PRESENT	0x077
112 #define DISK_IN		0x170
113 #define WRITE_PROT	0x171
114 #define TRACK_ZERO	0x172
115 #define TACHO		0x173
116 #define READ_DATA_1	0x174
117 #define GCR_MODE	0x175
118 #define SEEK_COMPLETE	0x176
119 #define TWOMEG_MEDIA	0x177
120 
121 /* Bits in handshake register */
122 
123 #define MARK_BYTE	0x01
124 #define CRC_ZERO	0x02
125 #define RDDATA		0x04
126 #define SENSE		0x08
127 #define MOTEN		0x10
128 #define ERROR		0x20
129 #define DAT2BYTE	0x40
130 #define DAT1BYTE	0x80
131 
132 /* bits in setup register */
133 
134 #define S_INV_WDATA	0x01
135 #define S_3_5_SELECT	0x02
136 #define S_GCR		0x04
137 #define S_FCLK_DIV2	0x08
138 #define S_ERROR_CORR	0x10
139 #define S_IBM_DRIVE	0x20
140 #define S_GCR_WRITE	0x40
141 #define S_TIMEOUT	0x80
142 
143 /* bits in mode register */
144 
145 #define CLFIFO		0x01
146 #define ENBL1		0x02
147 #define ENBL2		0x04
148 #define ACTION		0x08
149 #define WRITE_MODE	0x10
150 #define HEDSEL		0x20
151 #define MOTON		0x80
152 
153 /*----------------------------------------------------------------------------*/
154 
155 enum drive_location {
156 	INTERNAL_DRIVE = 0x02,
157 	EXTERNAL_DRIVE = 0x04,
158 };
159 
160 enum media_type {
161 	DD_MEDIA,
162 	HD_MEDIA,
163 };
164 
165 struct floppy_state {
166 
167 	/* physical properties */
168 
169 	enum drive_location location;	/* internal or external drive */
170 	int		 head_number;	/* single- or double-sided drive */
171 
172 	/* media */
173 
174 	int		 disk_in;
175 	int		 ejected;
176 	enum media_type	 type;
177 	int		 write_protected;
178 
179 	int		 total_secs;
180 	int		 secpercyl;
181 	int		 secpertrack;
182 
183 	/* in-use information */
184 
185 	int		track;
186 	int		ref_count;
187 
188 	struct gendisk *disk;
189 	struct blk_mq_tag_set tag_set;
190 
191 	/* parent controller */
192 
193 	struct swim_priv *swd;
194 };
195 
196 enum motor_action {
197 	OFF,
198 	ON,
199 };
200 
201 enum head {
202 	LOWER_HEAD = 0,
203 	UPPER_HEAD = 1,
204 };
205 
206 #define FD_MAX_UNIT	2
207 
208 struct swim_priv {
209 	struct swim __iomem *base;
210 	spinlock_t lock;
211 	int floppy_count;
212 	struct floppy_state unit[FD_MAX_UNIT];
213 };
214 
215 extern int swim_read_sector_header(struct swim __iomem *base,
216 				   struct sector_header *header);
217 extern int swim_read_sector_data(struct swim __iomem *base,
218 				 unsigned char *data);
219 
220 static DEFINE_MUTEX(swim_mutex);
221 static inline void set_swim_mode(struct swim __iomem *base, int enable)
222 {
223 	struct iwm __iomem *iwm_base;
224 	unsigned long flags;
225 
226 	if (!enable) {
227 		swim_write(base, mode0, 0xf8);
228 		return;
229 	}
230 
231 	iwm_base = (struct iwm __iomem *)base;
232 	local_irq_save(flags);
233 
234 	iwm_read(iwm_base, q7L);
235 	iwm_read(iwm_base, mtrOff);
236 	iwm_read(iwm_base, q6H);
237 
238 	iwm_write(iwm_base, q7H, 0x57);
239 	iwm_write(iwm_base, q7H, 0x17);
240 	iwm_write(iwm_base, q7H, 0x57);
241 	iwm_write(iwm_base, q7H, 0x57);
242 
243 	local_irq_restore(flags);
244 }
245 
246 static inline int get_swim_mode(struct swim __iomem *base)
247 {
248 	unsigned long flags;
249 
250 	local_irq_save(flags);
251 
252 	swim_write(base, phase, 0xf5);
253 	if (swim_read(base, phase) != 0xf5)
254 		goto is_iwm;
255 	swim_write(base, phase, 0xf6);
256 	if (swim_read(base, phase) != 0xf6)
257 		goto is_iwm;
258 	swim_write(base, phase, 0xf7);
259 	if (swim_read(base, phase) != 0xf7)
260 		goto is_iwm;
261 	local_irq_restore(flags);
262 	return 1;
263 is_iwm:
264 	local_irq_restore(flags);
265 	return 0;
266 }
267 
268 static inline void swim_select(struct swim __iomem *base, int sel)
269 {
270 	swim_write(base, phase, RELAX);
271 
272 	via1_set_head(sel & 0x100);
273 
274 	swim_write(base, phase, sel & CA_MASK);
275 }
276 
277 static inline void swim_action(struct swim __iomem *base, int action)
278 {
279 	unsigned long flags;
280 
281 	local_irq_save(flags);
282 
283 	swim_select(base, action);
284 	udelay(1);
285 	swim_write(base, phase, (LSTRB<<4) | LSTRB);
286 	udelay(1);
287 	swim_write(base, phase, (LSTRB<<4) | ((~LSTRB) & 0x0F));
288 	udelay(1);
289 
290 	local_irq_restore(flags);
291 }
292 
293 static inline int swim_readbit(struct swim __iomem *base, int bit)
294 {
295 	int stat;
296 
297 	swim_select(base, bit);
298 
299 	udelay(10);
300 
301 	stat = swim_read(base, handshake);
302 
303 	return (stat & SENSE) == 0;
304 }
305 
306 static inline void swim_drive(struct swim __iomem *base,
307 			      enum drive_location location)
308 {
309 	if (location == INTERNAL_DRIVE) {
310 		swim_write(base, mode0, EXTERNAL_DRIVE); /* clear drive 1 bit */
311 		swim_write(base, mode1, INTERNAL_DRIVE); /* set drive 0 bit */
312 	} else if (location == EXTERNAL_DRIVE) {
313 		swim_write(base, mode0, INTERNAL_DRIVE); /* clear drive 0 bit */
314 		swim_write(base, mode1, EXTERNAL_DRIVE); /* set drive 1 bit */
315 	}
316 }
317 
318 static inline void swim_motor(struct swim __iomem *base,
319 			      enum motor_action action)
320 {
321 	if (action == ON) {
322 		int i;
323 
324 		swim_action(base, MOTOR_ON);
325 
326 		for (i = 0; i < 2*HZ; i++) {
327 			swim_select(base, RELAX);
328 			if (swim_readbit(base, MOTOR_ON))
329 				break;
330 			set_current_state(TASK_INTERRUPTIBLE);
331 			schedule_timeout(1);
332 		}
333 	} else if (action == OFF) {
334 		swim_action(base, MOTOR_OFF);
335 		swim_select(base, RELAX);
336 	}
337 }
338 
339 static inline void swim_eject(struct swim __iomem *base)
340 {
341 	int i;
342 
343 	swim_action(base, EJECT);
344 
345 	for (i = 0; i < 2*HZ; i++) {
346 		swim_select(base, RELAX);
347 		if (!swim_readbit(base, DISK_IN))
348 			break;
349 		set_current_state(TASK_INTERRUPTIBLE);
350 		schedule_timeout(1);
351 	}
352 	swim_select(base, RELAX);
353 }
354 
355 static inline void swim_head(struct swim __iomem *base, enum head head)
356 {
357 	/* wait drive is ready */
358 
359 	if (head == UPPER_HEAD)
360 		swim_select(base, READ_DATA_1);
361 	else if (head == LOWER_HEAD)
362 		swim_select(base, READ_DATA_0);
363 }
364 
365 static inline int swim_step(struct swim __iomem *base)
366 {
367 	int wait;
368 
369 	swim_action(base, STEP);
370 
371 	for (wait = 0; wait < HZ; wait++) {
372 
373 		set_current_state(TASK_INTERRUPTIBLE);
374 		schedule_timeout(1);
375 
376 		swim_select(base, RELAX);
377 		if (!swim_readbit(base, STEP))
378 			return 0;
379 	}
380 	return -1;
381 }
382 
383 static inline int swim_track00(struct swim __iomem *base)
384 {
385 	int try;
386 
387 	swim_action(base, SEEK_NEGATIVE);
388 
389 	for (try = 0; try < 100; try++) {
390 
391 		swim_select(base, RELAX);
392 		if (swim_readbit(base, TRACK_ZERO))
393 			break;
394 
395 		if (swim_step(base))
396 			return -1;
397 	}
398 
399 	if (swim_readbit(base, TRACK_ZERO))
400 		return 0;
401 
402 	return -1;
403 }
404 
405 static inline int swim_seek(struct swim __iomem *base, int step)
406 {
407 	if (step == 0)
408 		return 0;
409 
410 	if (step < 0) {
411 		swim_action(base, SEEK_NEGATIVE);
412 		step = -step;
413 	} else
414 		swim_action(base, SEEK_POSITIVE);
415 
416 	for ( ; step > 0; step--) {
417 		if (swim_step(base))
418 			return -1;
419 	}
420 
421 	return 0;
422 }
423 
424 static inline int swim_track(struct floppy_state *fs,  int track)
425 {
426 	struct swim __iomem *base = fs->swd->base;
427 	int ret;
428 
429 	ret = swim_seek(base, track - fs->track);
430 
431 	if (ret == 0)
432 		fs->track = track;
433 	else {
434 		swim_track00(base);
435 		fs->track = 0;
436 	}
437 
438 	return ret;
439 }
440 
441 static int floppy_eject(struct floppy_state *fs)
442 {
443 	struct swim __iomem *base = fs->swd->base;
444 
445 	swim_drive(base, fs->location);
446 	swim_motor(base, OFF);
447 	swim_eject(base);
448 
449 	fs->disk_in = 0;
450 	fs->ejected = 1;
451 
452 	return 0;
453 }
454 
455 static inline int swim_read_sector(struct floppy_state *fs,
456 				   int side, int track,
457 				   int sector, unsigned char *buffer)
458 {
459 	struct swim __iomem *base = fs->swd->base;
460 	unsigned long flags;
461 	struct sector_header header;
462 	int ret = -1;
463 	short i;
464 
465 	swim_track(fs, track);
466 
467 	swim_write(base, mode1, MOTON);
468 	swim_head(base, side);
469 	swim_write(base, mode0, side);
470 
471 	local_irq_save(flags);
472 	for (i = 0; i < 36; i++) {
473 		ret = swim_read_sector_header(base, &header);
474 		if (!ret && (header.sector == sector)) {
475 			/* found */
476 
477 			ret = swim_read_sector_data(base, buffer);
478 			break;
479 		}
480 	}
481 	local_irq_restore(flags);
482 
483 	swim_write(base, mode0, MOTON);
484 
485 	if ((header.side != side)  || (header.track != track) ||
486 	     (header.sector != sector))
487 		return 0;
488 
489 	return ret;
490 }
491 
492 static blk_status_t floppy_read_sectors(struct floppy_state *fs,
493 			       int req_sector, int sectors_nb,
494 			       unsigned char *buffer)
495 {
496 	struct swim __iomem *base = fs->swd->base;
497 	int ret;
498 	int side, track, sector;
499 	int i, try;
500 
501 
502 	swim_drive(base, fs->location);
503 	for (i = req_sector; i < req_sector + sectors_nb; i++) {
504 		int x;
505 		track = i / fs->secpercyl;
506 		x = i % fs->secpercyl;
507 		side = x / fs->secpertrack;
508 		sector = x % fs->secpertrack + 1;
509 
510 		try = 5;
511 		do {
512 			ret = swim_read_sector(fs, side, track, sector,
513 						buffer);
514 			if (try-- == 0)
515 				return BLK_STS_IOERR;
516 		} while (ret != 512);
517 
518 		buffer += ret;
519 	}
520 
521 	return 0;
522 }
523 
524 static blk_status_t swim_queue_rq(struct blk_mq_hw_ctx *hctx,
525 				  const struct blk_mq_queue_data *bd)
526 {
527 	struct floppy_state *fs = hctx->queue->queuedata;
528 	struct swim_priv *swd = fs->swd;
529 	struct request *req = bd->rq;
530 	blk_status_t err;
531 
532 	if (!spin_trylock_irq(&swd->lock))
533 		return BLK_STS_DEV_RESOURCE;
534 
535 	blk_mq_start_request(req);
536 
537 	if (!fs->disk_in || rq_data_dir(req) == WRITE) {
538 		err = BLK_STS_IOERR;
539 		goto out;
540 	}
541 
542 	do {
543 		err = floppy_read_sectors(fs, blk_rq_pos(req),
544 					  blk_rq_cur_sectors(req),
545 					  bio_data(req->bio));
546 	} while (blk_update_request(req, err, blk_rq_cur_bytes(req)));
547 	__blk_mq_end_request(req, err);
548 
549 	err = BLK_STS_OK;
550 out:
551 	spin_unlock_irq(&swd->lock);
552 	return err;
553 
554 }
555 
556 static struct floppy_struct floppy_type[4] = {
557 	{    0,  0, 0,  0, 0, 0x00, 0x00, 0x00, 0x00, NULL }, /* no testing   */
558 	{  720,  9, 1, 80, 0, 0x2A, 0x02, 0xDF, 0x50, NULL }, /* 360KB SS 3.5"*/
559 	{ 1440,  9, 2, 80, 0, 0x2A, 0x02, 0xDF, 0x50, NULL }, /* 720KB 3.5"   */
560 	{ 2880, 18, 2, 80, 0, 0x1B, 0x00, 0xCF, 0x6C, NULL }, /* 1.44MB 3.5"  */
561 };
562 
563 static int get_floppy_geometry(struct floppy_state *fs, int type,
564 			       struct floppy_struct **g)
565 {
566 	if (type >= ARRAY_SIZE(floppy_type))
567 		return -EINVAL;
568 
569 	if (type)
570 		*g = &floppy_type[type];
571 	else if (fs->type == HD_MEDIA) /* High-Density media */
572 		*g = &floppy_type[3];
573 	else if (fs->head_number == 2) /* double-sided */
574 		*g = &floppy_type[2];
575 	else
576 		*g = &floppy_type[1];
577 
578 	return 0;
579 }
580 
581 static void setup_medium(struct floppy_state *fs)
582 {
583 	struct swim __iomem *base = fs->swd->base;
584 
585 	if (swim_readbit(base, DISK_IN)) {
586 		struct floppy_struct *g;
587 		fs->disk_in = 1;
588 		fs->write_protected = swim_readbit(base, WRITE_PROT);
589 
590 		if (swim_track00(base))
591 			printk(KERN_ERR
592 				"SWIM: cannot move floppy head to track 0\n");
593 
594 		swim_track00(base);
595 
596 		fs->type = swim_readbit(base, TWOMEG_MEDIA) ?
597 			HD_MEDIA : DD_MEDIA;
598 		fs->head_number = swim_readbit(base, SINGLE_SIDED) ? 1 : 2;
599 		get_floppy_geometry(fs, 0, &g);
600 		fs->total_secs = g->size;
601 		fs->secpercyl = g->head * g->sect;
602 		fs->secpertrack = g->sect;
603 		fs->track = 0;
604 	} else {
605 		fs->disk_in = 0;
606 	}
607 }
608 
609 static int floppy_open(struct block_device *bdev, fmode_t mode)
610 {
611 	struct floppy_state *fs = bdev->bd_disk->private_data;
612 	struct swim __iomem *base = fs->swd->base;
613 	int err;
614 
615 	if (fs->ref_count == -1 || (fs->ref_count && mode & FMODE_EXCL))
616 		return -EBUSY;
617 
618 	if (mode & FMODE_EXCL)
619 		fs->ref_count = -1;
620 	else
621 		fs->ref_count++;
622 
623 	swim_write(base, setup, S_IBM_DRIVE  | S_FCLK_DIV2);
624 	udelay(10);
625 	swim_drive(base, fs->location);
626 	swim_motor(base, ON);
627 	swim_action(base, SETMFM);
628 	if (fs->ejected)
629 		setup_medium(fs);
630 	if (!fs->disk_in) {
631 		err = -ENXIO;
632 		goto out;
633 	}
634 
635 	set_capacity(fs->disk, fs->total_secs);
636 
637 	if (mode & FMODE_NDELAY)
638 		return 0;
639 
640 	if (mode & (FMODE_READ|FMODE_WRITE)) {
641 		if (bdev_check_media_change(bdev) && fs->disk_in)
642 			fs->ejected = 0;
643 		if ((mode & FMODE_WRITE) && fs->write_protected) {
644 			err = -EROFS;
645 			goto out;
646 		}
647 	}
648 	return 0;
649 out:
650 	if (fs->ref_count < 0)
651 		fs->ref_count = 0;
652 	else if (fs->ref_count > 0)
653 		--fs->ref_count;
654 
655 	if (fs->ref_count == 0)
656 		swim_motor(base, OFF);
657 	return err;
658 }
659 
660 static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
661 {
662 	int ret;
663 
664 	mutex_lock(&swim_mutex);
665 	ret = floppy_open(bdev, mode);
666 	mutex_unlock(&swim_mutex);
667 
668 	return ret;
669 }
670 
671 static void floppy_release(struct gendisk *disk, fmode_t mode)
672 {
673 	struct floppy_state *fs = disk->private_data;
674 	struct swim __iomem *base = fs->swd->base;
675 
676 	mutex_lock(&swim_mutex);
677 	if (fs->ref_count < 0)
678 		fs->ref_count = 0;
679 	else if (fs->ref_count > 0)
680 		--fs->ref_count;
681 
682 	if (fs->ref_count == 0)
683 		swim_motor(base, OFF);
684 	mutex_unlock(&swim_mutex);
685 }
686 
687 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
688 			unsigned int cmd, unsigned long param)
689 {
690 	struct floppy_state *fs = bdev->bd_disk->private_data;
691 	int err;
692 
693 	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
694 			return -EPERM;
695 
696 	switch (cmd) {
697 	case FDEJECT:
698 		if (fs->ref_count != 1)
699 			return -EBUSY;
700 		mutex_lock(&swim_mutex);
701 		err = floppy_eject(fs);
702 		mutex_unlock(&swim_mutex);
703 		return err;
704 
705 	case FDGETPRM:
706 		if (copy_to_user((void __user *) param, (void *) &floppy_type,
707 				 sizeof(struct floppy_struct)))
708 			return -EFAULT;
709 		return 0;
710 	}
711 	return -ENOTTY;
712 }
713 
714 static int floppy_getgeo(struct block_device *bdev, struct hd_geometry *geo)
715 {
716 	struct floppy_state *fs = bdev->bd_disk->private_data;
717 	struct floppy_struct *g;
718 	int ret;
719 
720 	ret = get_floppy_geometry(fs, 0, &g);
721 	if (ret)
722 		return ret;
723 
724 	geo->heads = g->head;
725 	geo->sectors = g->sect;
726 	geo->cylinders = g->track;
727 
728 	return 0;
729 }
730 
731 static unsigned int floppy_check_events(struct gendisk *disk,
732 					unsigned int clearing)
733 {
734 	struct floppy_state *fs = disk->private_data;
735 
736 	return fs->ejected ? DISK_EVENT_MEDIA_CHANGE : 0;
737 }
738 
739 static const struct block_device_operations floppy_fops = {
740 	.owner		 = THIS_MODULE,
741 	.open		 = floppy_unlocked_open,
742 	.release	 = floppy_release,
743 	.ioctl		 = floppy_ioctl,
744 	.getgeo		 = floppy_getgeo,
745 	.check_events	 = floppy_check_events,
746 };
747 
748 static int swim_add_floppy(struct swim_priv *swd, enum drive_location location)
749 {
750 	struct floppy_state *fs = &swd->unit[swd->floppy_count];
751 	struct swim __iomem *base = swd->base;
752 
753 	fs->location = location;
754 
755 	swim_drive(base, location);
756 
757 	swim_motor(base, OFF);
758 
759 	fs->type = HD_MEDIA;
760 	fs->head_number = 2;
761 
762 	fs->ref_count = 0;
763 	fs->ejected = 1;
764 
765 	swd->floppy_count++;
766 
767 	return 0;
768 }
769 
770 static const struct blk_mq_ops swim_mq_ops = {
771 	.queue_rq = swim_queue_rq,
772 };
773 
774 static int swim_floppy_init(struct swim_priv *swd)
775 {
776 	int err;
777 	int drive;
778 	struct swim __iomem *base = swd->base;
779 
780 	/* scan floppy drives */
781 
782 	swim_drive(base, INTERNAL_DRIVE);
783 	if (swim_readbit(base, DRIVE_PRESENT) &&
784 	    !swim_readbit(base, ONEMEG_DRIVE))
785 		swim_add_floppy(swd, INTERNAL_DRIVE);
786 	swim_drive(base, EXTERNAL_DRIVE);
787 	if (swim_readbit(base, DRIVE_PRESENT) &&
788 	    !swim_readbit(base, ONEMEG_DRIVE))
789 		swim_add_floppy(swd, EXTERNAL_DRIVE);
790 
791 	/* register floppy drives */
792 
793 	err = register_blkdev(FLOPPY_MAJOR, "fd");
794 	if (err) {
795 		printk(KERN_ERR "Unable to get major %d for SWIM floppy\n",
796 		       FLOPPY_MAJOR);
797 		return -EBUSY;
798 	}
799 
800 	spin_lock_init(&swd->lock);
801 
802 	for (drive = 0; drive < swd->floppy_count; drive++) {
803 		err = blk_mq_alloc_sq_tag_set(&swd->unit[drive].tag_set,
804 				&swim_mq_ops, 2, BLK_MQ_F_SHOULD_MERGE);
805 		if (err)
806 			goto exit_put_disks;
807 
808 		swd->unit[drive].disk =
809 			blk_mq_alloc_disk(&swd->unit[drive].tag_set,
810 					  &swd->unit[drive]);
811 		if (IS_ERR(swd->unit[drive].disk)) {
812 			blk_mq_free_tag_set(&swd->unit[drive].tag_set);
813 			err = PTR_ERR(swd->unit[drive].disk);
814 			goto exit_put_disks;
815 		}
816 
817 		swd->unit[drive].swd = swd;
818 	}
819 
820 	for (drive = 0; drive < swd->floppy_count; drive++) {
821 		swd->unit[drive].disk->flags = GENHD_FL_REMOVABLE;
822 		swd->unit[drive].disk->major = FLOPPY_MAJOR;
823 		swd->unit[drive].disk->first_minor = drive;
824 		swd->unit[drive].disk->minors = 1;
825 		sprintf(swd->unit[drive].disk->disk_name, "fd%d", drive);
826 		swd->unit[drive].disk->fops = &floppy_fops;
827 		swd->unit[drive].disk->events = DISK_EVENT_MEDIA_CHANGE;
828 		swd->unit[drive].disk->private_data = &swd->unit[drive];
829 		set_capacity(swd->unit[drive].disk, 2880);
830 		add_disk(swd->unit[drive].disk);
831 	}
832 
833 	return 0;
834 
835 exit_put_disks:
836 	unregister_blkdev(FLOPPY_MAJOR, "fd");
837 	do {
838 		struct gendisk *disk = swd->unit[drive].disk;
839 
840 		if (!disk)
841 			continue;
842 		blk_cleanup_disk(disk);
843 		blk_mq_free_tag_set(&swd->unit[drive].tag_set);
844 	} while (drive--);
845 	return err;
846 }
847 
848 static int swim_probe(struct platform_device *dev)
849 {
850 	struct resource *res;
851 	struct swim __iomem *swim_base;
852 	struct swim_priv *swd;
853 	int ret;
854 
855 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
856 	if (!res) {
857 		ret = -ENODEV;
858 		goto out;
859 	}
860 
861 	if (!request_mem_region(res->start, resource_size(res), CARDNAME)) {
862 		ret = -EBUSY;
863 		goto out;
864 	}
865 
866 	swim_base = (struct swim __iomem *)res->start;
867 	if (!swim_base) {
868 		ret = -ENOMEM;
869 		goto out_release_io;
870 	}
871 
872 	/* probe device */
873 
874 	set_swim_mode(swim_base, 1);
875 	if (!get_swim_mode(swim_base)) {
876 		printk(KERN_INFO "SWIM device not found !\n");
877 		ret = -ENODEV;
878 		goto out_release_io;
879 	}
880 
881 	/* set platform driver data */
882 
883 	swd = kzalloc(sizeof(struct swim_priv), GFP_KERNEL);
884 	if (!swd) {
885 		ret = -ENOMEM;
886 		goto out_release_io;
887 	}
888 	platform_set_drvdata(dev, swd);
889 
890 	swd->base = swim_base;
891 
892 	ret = swim_floppy_init(swd);
893 	if (ret)
894 		goto out_kfree;
895 
896 	return 0;
897 
898 out_kfree:
899 	kfree(swd);
900 out_release_io:
901 	release_mem_region(res->start, resource_size(res));
902 out:
903 	return ret;
904 }
905 
906 static int swim_remove(struct platform_device *dev)
907 {
908 	struct swim_priv *swd = platform_get_drvdata(dev);
909 	int drive;
910 	struct resource *res;
911 
912 	for (drive = 0; drive < swd->floppy_count; drive++) {
913 		del_gendisk(swd->unit[drive].disk);
914 		blk_cleanup_queue(swd->unit[drive].disk->queue);
915 		blk_mq_free_tag_set(&swd->unit[drive].tag_set);
916 		put_disk(swd->unit[drive].disk);
917 	}
918 
919 	unregister_blkdev(FLOPPY_MAJOR, "fd");
920 
921 	/* eject floppies */
922 
923 	for (drive = 0; drive < swd->floppy_count; drive++)
924 		floppy_eject(&swd->unit[drive]);
925 
926 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
927 	if (res)
928 		release_mem_region(res->start, resource_size(res));
929 
930 	kfree(swd);
931 
932 	return 0;
933 }
934 
935 static struct platform_driver swim_driver = {
936 	.probe  = swim_probe,
937 	.remove = swim_remove,
938 	.driver   = {
939 		.name	= CARDNAME,
940 	},
941 };
942 
943 static int __init swim_init(void)
944 {
945 	printk(KERN_INFO "SWIM floppy driver %s\n", DRIVER_VERSION);
946 
947 	return platform_driver_register(&swim_driver);
948 }
949 module_init(swim_init);
950 
951 static void __exit swim_exit(void)
952 {
953 	platform_driver_unregister(&swim_driver);
954 }
955 module_exit(swim_exit);
956 
957 MODULE_DESCRIPTION("Driver for SWIM floppy controller");
958 MODULE_LICENSE("GPL");
959 MODULE_AUTHOR("Laurent Vivier <laurent@lvivier.info>");
960 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
961