xref: /openbmc/linux/drivers/block/swim.c (revision b868a02e)
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/major.h>
20 #include <linux/mutex.h>
21 #include <linux/hdreg.h>
22 #include <linux/kernel.h>
23 #include <linux/delay.h>
24 #include <linux/platform_device.h>
25 
26 #include <asm/mac_via.h>
27 
28 #define CARDNAME "swim"
29 
30 struct sector_header {
31 	unsigned char side;
32 	unsigned char track;
33 	unsigned char sector;
34 	unsigned char size;
35 	unsigned char crc0;
36 	unsigned char crc1;
37 } __attribute__((packed));
38 
39 #define DRIVER_VERSION "Version 0.2 (2008-10-30)"
40 
41 #define REG(x)	unsigned char x, x ## _pad[0x200 - 1];
42 
43 struct swim {
44 	REG(write_data)
45 	REG(write_mark)
46 	REG(write_CRC)
47 	REG(write_parameter)
48 	REG(write_phase)
49 	REG(write_setup)
50 	REG(write_mode0)
51 	REG(write_mode1)
52 
53 	REG(read_data)
54 	REG(read_mark)
55 	REG(read_error)
56 	REG(read_parameter)
57 	REG(read_phase)
58 	REG(read_setup)
59 	REG(read_status)
60 	REG(read_handshake)
61 } __attribute__((packed));
62 
63 #define swim_write(base, reg, v) 	out_8(&(base)->write_##reg, (v))
64 #define swim_read(base, reg)		in_8(&(base)->read_##reg)
65 
66 /* IWM registers */
67 
68 struct iwm {
69 	REG(ph0L)
70 	REG(ph0H)
71 	REG(ph1L)
72 	REG(ph1H)
73 	REG(ph2L)
74 	REG(ph2H)
75 	REG(ph3L)
76 	REG(ph3H)
77 	REG(mtrOff)
78 	REG(mtrOn)
79 	REG(intDrive)
80 	REG(extDrive)
81 	REG(q6L)
82 	REG(q6H)
83 	REG(q7L)
84 	REG(q7H)
85 } __attribute__((packed));
86 
87 #define iwm_write(base, reg, v) 	out_8(&(base)->reg, (v))
88 #define iwm_read(base, reg)		in_8(&(base)->reg)
89 
90 /* bits in phase register */
91 
92 #define SEEK_POSITIVE	0x070
93 #define SEEK_NEGATIVE	0x074
94 #define STEP		0x071
95 #define MOTOR_ON	0x072
96 #define MOTOR_OFF	0x076
97 #define INDEX		0x073
98 #define EJECT		0x077
99 #define SETMFM		0x171
100 #define SETGCR		0x175
101 
102 #define RELAX		0x033
103 #define LSTRB		0x008
104 
105 #define CA_MASK		0x077
106 
107 /* Select values for swim_select and swim_readbit */
108 
109 #define READ_DATA_0	0x074
110 #define ONEMEG_DRIVE	0x075
111 #define SINGLE_SIDED	0x076
112 #define DRIVE_PRESENT	0x077
113 #define DISK_IN		0x170
114 #define WRITE_PROT	0x171
115 #define TRACK_ZERO	0x172
116 #define TACHO		0x173
117 #define READ_DATA_1	0x174
118 #define GCR_MODE	0x175
119 #define SEEK_COMPLETE	0x176
120 #define TWOMEG_MEDIA	0x177
121 
122 /* Bits in handshake register */
123 
124 #define MARK_BYTE	0x01
125 #define CRC_ZERO	0x02
126 #define RDDATA		0x04
127 #define SENSE		0x08
128 #define MOTEN		0x10
129 #define ERROR		0x20
130 #define DAT2BYTE	0x40
131 #define DAT1BYTE	0x80
132 
133 /* bits in setup register */
134 
135 #define S_INV_WDATA	0x01
136 #define S_3_5_SELECT	0x02
137 #define S_GCR		0x04
138 #define S_FCLK_DIV2	0x08
139 #define S_ERROR_CORR	0x10
140 #define S_IBM_DRIVE	0x20
141 #define S_GCR_WRITE	0x40
142 #define S_TIMEOUT	0x80
143 
144 /* bits in mode register */
145 
146 #define CLFIFO		0x01
147 #define ENBL1		0x02
148 #define ENBL2		0x04
149 #define ACTION		0x08
150 #define WRITE_MODE	0x10
151 #define HEDSEL		0x20
152 #define MOTON		0x80
153 
154 /*----------------------------------------------------------------------------*/
155 
156 enum drive_location {
157 	INTERNAL_DRIVE = 0x02,
158 	EXTERNAL_DRIVE = 0x04,
159 };
160 
161 enum media_type {
162 	DD_MEDIA,
163 	HD_MEDIA,
164 };
165 
166 struct floppy_state {
167 
168 	/* physical properties */
169 
170 	enum drive_location location;	/* internal or external drive */
171 	int		 head_number;	/* single- or double-sided drive */
172 
173 	/* media */
174 
175 	int		 disk_in;
176 	int		 ejected;
177 	enum media_type	 type;
178 	int		 write_protected;
179 
180 	int		 total_secs;
181 	int		 secpercyl;
182 	int		 secpertrack;
183 
184 	/* in-use information */
185 
186 	int		track;
187 	int		ref_count;
188 	bool registered;
189 
190 	struct gendisk *disk;
191 	struct blk_mq_tag_set tag_set;
192 
193 	/* parent controller */
194 
195 	struct swim_priv *swd;
196 };
197 
198 enum motor_action {
199 	OFF,
200 	ON,
201 };
202 
203 enum head {
204 	LOWER_HEAD = 0,
205 	UPPER_HEAD = 1,
206 };
207 
208 #define FD_MAX_UNIT	2
209 
210 struct swim_priv {
211 	struct swim __iomem *base;
212 	spinlock_t lock;
213 	int floppy_count;
214 	struct floppy_state unit[FD_MAX_UNIT];
215 };
216 
217 extern int swim_read_sector_header(struct swim __iomem *base,
218 				   struct sector_header *header);
219 extern int swim_read_sector_data(struct swim __iomem *base,
220 				 unsigned char *data);
221 
222 static DEFINE_MUTEX(swim_mutex);
223 static inline void set_swim_mode(struct swim __iomem *base, int enable)
224 {
225 	struct iwm __iomem *iwm_base;
226 	unsigned long flags;
227 
228 	if (!enable) {
229 		swim_write(base, mode0, 0xf8);
230 		return;
231 	}
232 
233 	iwm_base = (struct iwm __iomem *)base;
234 	local_irq_save(flags);
235 
236 	iwm_read(iwm_base, q7L);
237 	iwm_read(iwm_base, mtrOff);
238 	iwm_read(iwm_base, q6H);
239 
240 	iwm_write(iwm_base, q7H, 0x57);
241 	iwm_write(iwm_base, q7H, 0x17);
242 	iwm_write(iwm_base, q7H, 0x57);
243 	iwm_write(iwm_base, q7H, 0x57);
244 
245 	local_irq_restore(flags);
246 }
247 
248 static inline int get_swim_mode(struct swim __iomem *base)
249 {
250 	unsigned long flags;
251 
252 	local_irq_save(flags);
253 
254 	swim_write(base, phase, 0xf5);
255 	if (swim_read(base, phase) != 0xf5)
256 		goto is_iwm;
257 	swim_write(base, phase, 0xf6);
258 	if (swim_read(base, phase) != 0xf6)
259 		goto is_iwm;
260 	swim_write(base, phase, 0xf7);
261 	if (swim_read(base, phase) != 0xf7)
262 		goto is_iwm;
263 	local_irq_restore(flags);
264 	return 1;
265 is_iwm:
266 	local_irq_restore(flags);
267 	return 0;
268 }
269 
270 static inline void swim_select(struct swim __iomem *base, int sel)
271 {
272 	swim_write(base, phase, RELAX);
273 
274 	via1_set_head(sel & 0x100);
275 
276 	swim_write(base, phase, sel & CA_MASK);
277 }
278 
279 static inline void swim_action(struct swim __iomem *base, int action)
280 {
281 	unsigned long flags;
282 
283 	local_irq_save(flags);
284 
285 	swim_select(base, action);
286 	udelay(1);
287 	swim_write(base, phase, (LSTRB<<4) | LSTRB);
288 	udelay(1);
289 	swim_write(base, phase, (LSTRB<<4) | ((~LSTRB) & 0x0F));
290 	udelay(1);
291 
292 	local_irq_restore(flags);
293 }
294 
295 static inline int swim_readbit(struct swim __iomem *base, int bit)
296 {
297 	int stat;
298 
299 	swim_select(base, bit);
300 
301 	udelay(10);
302 
303 	stat = swim_read(base, handshake);
304 
305 	return (stat & SENSE) == 0;
306 }
307 
308 static inline void swim_drive(struct swim __iomem *base,
309 			      enum drive_location location)
310 {
311 	if (location == INTERNAL_DRIVE) {
312 		swim_write(base, mode0, EXTERNAL_DRIVE); /* clear drive 1 bit */
313 		swim_write(base, mode1, INTERNAL_DRIVE); /* set drive 0 bit */
314 	} else if (location == EXTERNAL_DRIVE) {
315 		swim_write(base, mode0, INTERNAL_DRIVE); /* clear drive 0 bit */
316 		swim_write(base, mode1, EXTERNAL_DRIVE); /* set drive 1 bit */
317 	}
318 }
319 
320 static inline void swim_motor(struct swim __iomem *base,
321 			      enum motor_action action)
322 {
323 	if (action == ON) {
324 		int i;
325 
326 		swim_action(base, MOTOR_ON);
327 
328 		for (i = 0; i < 2*HZ; i++) {
329 			swim_select(base, RELAX);
330 			if (swim_readbit(base, MOTOR_ON))
331 				break;
332 			set_current_state(TASK_INTERRUPTIBLE);
333 			schedule_timeout(1);
334 		}
335 	} else if (action == OFF) {
336 		swim_action(base, MOTOR_OFF);
337 		swim_select(base, RELAX);
338 	}
339 }
340 
341 static inline void swim_eject(struct swim __iomem *base)
342 {
343 	int i;
344 
345 	swim_action(base, EJECT);
346 
347 	for (i = 0; i < 2*HZ; i++) {
348 		swim_select(base, RELAX);
349 		if (!swim_readbit(base, DISK_IN))
350 			break;
351 		set_current_state(TASK_INTERRUPTIBLE);
352 		schedule_timeout(1);
353 	}
354 	swim_select(base, RELAX);
355 }
356 
357 static inline void swim_head(struct swim __iomem *base, enum head head)
358 {
359 	/* wait drive is ready */
360 
361 	if (head == UPPER_HEAD)
362 		swim_select(base, READ_DATA_1);
363 	else if (head == LOWER_HEAD)
364 		swim_select(base, READ_DATA_0);
365 }
366 
367 static inline int swim_step(struct swim __iomem *base)
368 {
369 	int wait;
370 
371 	swim_action(base, STEP);
372 
373 	for (wait = 0; wait < HZ; wait++) {
374 
375 		set_current_state(TASK_INTERRUPTIBLE);
376 		schedule_timeout(1);
377 
378 		swim_select(base, RELAX);
379 		if (!swim_readbit(base, STEP))
380 			return 0;
381 	}
382 	return -1;
383 }
384 
385 static inline int swim_track00(struct swim __iomem *base)
386 {
387 	int try;
388 
389 	swim_action(base, SEEK_NEGATIVE);
390 
391 	for (try = 0; try < 100; try++) {
392 
393 		swim_select(base, RELAX);
394 		if (swim_readbit(base, TRACK_ZERO))
395 			break;
396 
397 		if (swim_step(base))
398 			return -1;
399 	}
400 
401 	if (swim_readbit(base, TRACK_ZERO))
402 		return 0;
403 
404 	return -1;
405 }
406 
407 static inline int swim_seek(struct swim __iomem *base, int step)
408 {
409 	if (step == 0)
410 		return 0;
411 
412 	if (step < 0) {
413 		swim_action(base, SEEK_NEGATIVE);
414 		step = -step;
415 	} else
416 		swim_action(base, SEEK_POSITIVE);
417 
418 	for ( ; step > 0; step--) {
419 		if (swim_step(base))
420 			return -1;
421 	}
422 
423 	return 0;
424 }
425 
426 static inline int swim_track(struct floppy_state *fs,  int track)
427 {
428 	struct swim __iomem *base = fs->swd->base;
429 	int ret;
430 
431 	ret = swim_seek(base, track - fs->track);
432 
433 	if (ret == 0)
434 		fs->track = track;
435 	else {
436 		swim_track00(base);
437 		fs->track = 0;
438 	}
439 
440 	return ret;
441 }
442 
443 static int floppy_eject(struct floppy_state *fs)
444 {
445 	struct swim __iomem *base = fs->swd->base;
446 
447 	swim_drive(base, fs->location);
448 	swim_motor(base, OFF);
449 	swim_eject(base);
450 
451 	fs->disk_in = 0;
452 	fs->ejected = 1;
453 
454 	return 0;
455 }
456 
457 static inline int swim_read_sector(struct floppy_state *fs,
458 				   int side, int track,
459 				   int sector, unsigned char *buffer)
460 {
461 	struct swim __iomem *base = fs->swd->base;
462 	unsigned long flags;
463 	struct sector_header header;
464 	int ret = -1;
465 	short i;
466 
467 	swim_track(fs, track);
468 
469 	swim_write(base, mode1, MOTON);
470 	swim_head(base, side);
471 	swim_write(base, mode0, side);
472 
473 	local_irq_save(flags);
474 	for (i = 0; i < 36; i++) {
475 		ret = swim_read_sector_header(base, &header);
476 		if (!ret && (header.sector == sector)) {
477 			/* found */
478 
479 			ret = swim_read_sector_data(base, buffer);
480 			break;
481 		}
482 	}
483 	local_irq_restore(flags);
484 
485 	swim_write(base, mode0, MOTON);
486 
487 	if ((header.side != side)  || (header.track != track) ||
488 	     (header.sector != sector))
489 		return 0;
490 
491 	return ret;
492 }
493 
494 static blk_status_t floppy_read_sectors(struct floppy_state *fs,
495 			       int req_sector, int sectors_nb,
496 			       unsigned char *buffer)
497 {
498 	struct swim __iomem *base = fs->swd->base;
499 	int ret;
500 	int side, track, sector;
501 	int i, try;
502 
503 
504 	swim_drive(base, fs->location);
505 	for (i = req_sector; i < req_sector + sectors_nb; i++) {
506 		int x;
507 		track = i / fs->secpercyl;
508 		x = i % fs->secpercyl;
509 		side = x / fs->secpertrack;
510 		sector = x % fs->secpertrack + 1;
511 
512 		try = 5;
513 		do {
514 			ret = swim_read_sector(fs, side, track, sector,
515 						buffer);
516 			if (try-- == 0)
517 				return BLK_STS_IOERR;
518 		} while (ret != 512);
519 
520 		buffer += ret;
521 	}
522 
523 	return 0;
524 }
525 
526 static blk_status_t swim_queue_rq(struct blk_mq_hw_ctx *hctx,
527 				  const struct blk_mq_queue_data *bd)
528 {
529 	struct floppy_state *fs = hctx->queue->queuedata;
530 	struct swim_priv *swd = fs->swd;
531 	struct request *req = bd->rq;
532 	blk_status_t err;
533 
534 	if (!spin_trylock_irq(&swd->lock))
535 		return BLK_STS_DEV_RESOURCE;
536 
537 	blk_mq_start_request(req);
538 
539 	if (!fs->disk_in || rq_data_dir(req) == WRITE) {
540 		err = BLK_STS_IOERR;
541 		goto out;
542 	}
543 
544 	do {
545 		err = floppy_read_sectors(fs, blk_rq_pos(req),
546 					  blk_rq_cur_sectors(req),
547 					  bio_data(req->bio));
548 	} while (blk_update_request(req, err, blk_rq_cur_bytes(req)));
549 	__blk_mq_end_request(req, err);
550 
551 	err = BLK_STS_OK;
552 out:
553 	spin_unlock_irq(&swd->lock);
554 	return err;
555 
556 }
557 
558 static struct floppy_struct floppy_type[4] = {
559 	{    0,  0, 0,  0, 0, 0x00, 0x00, 0x00, 0x00, NULL }, /* no testing   */
560 	{  720,  9, 1, 80, 0, 0x2A, 0x02, 0xDF, 0x50, NULL }, /* 360KB SS 3.5"*/
561 	{ 1440,  9, 2, 80, 0, 0x2A, 0x02, 0xDF, 0x50, NULL }, /* 720KB 3.5"   */
562 	{ 2880, 18, 2, 80, 0, 0x1B, 0x00, 0xCF, 0x6C, NULL }, /* 1.44MB 3.5"  */
563 };
564 
565 static int get_floppy_geometry(struct floppy_state *fs, int type,
566 			       struct floppy_struct **g)
567 {
568 	if (type >= ARRAY_SIZE(floppy_type))
569 		return -EINVAL;
570 
571 	if (type)
572 		*g = &floppy_type[type];
573 	else if (fs->type == HD_MEDIA) /* High-Density media */
574 		*g = &floppy_type[3];
575 	else if (fs->head_number == 2) /* double-sided */
576 		*g = &floppy_type[2];
577 	else
578 		*g = &floppy_type[1];
579 
580 	return 0;
581 }
582 
583 static void setup_medium(struct floppy_state *fs)
584 {
585 	struct swim __iomem *base = fs->swd->base;
586 
587 	if (swim_readbit(base, DISK_IN)) {
588 		struct floppy_struct *g;
589 		fs->disk_in = 1;
590 		fs->write_protected = swim_readbit(base, WRITE_PROT);
591 
592 		if (swim_track00(base))
593 			printk(KERN_ERR
594 				"SWIM: cannot move floppy head to track 0\n");
595 
596 		swim_track00(base);
597 
598 		fs->type = swim_readbit(base, TWOMEG_MEDIA) ?
599 			HD_MEDIA : DD_MEDIA;
600 		fs->head_number = swim_readbit(base, SINGLE_SIDED) ? 1 : 2;
601 		get_floppy_geometry(fs, 0, &g);
602 		fs->total_secs = g->size;
603 		fs->secpercyl = g->head * g->sect;
604 		fs->secpertrack = g->sect;
605 		fs->track = 0;
606 	} else {
607 		fs->disk_in = 0;
608 	}
609 }
610 
611 static int floppy_open(struct block_device *bdev, fmode_t mode)
612 {
613 	struct floppy_state *fs = bdev->bd_disk->private_data;
614 	struct swim __iomem *base = fs->swd->base;
615 	int err;
616 
617 	if (fs->ref_count == -1 || (fs->ref_count && mode & FMODE_EXCL))
618 		return -EBUSY;
619 
620 	if (mode & FMODE_EXCL)
621 		fs->ref_count = -1;
622 	else
623 		fs->ref_count++;
624 
625 	swim_write(base, setup, S_IBM_DRIVE  | S_FCLK_DIV2);
626 	udelay(10);
627 	swim_drive(base, fs->location);
628 	swim_motor(base, ON);
629 	swim_action(base, SETMFM);
630 	if (fs->ejected)
631 		setup_medium(fs);
632 	if (!fs->disk_in) {
633 		err = -ENXIO;
634 		goto out;
635 	}
636 
637 	set_capacity(fs->disk, fs->total_secs);
638 
639 	if (mode & FMODE_NDELAY)
640 		return 0;
641 
642 	if (mode & (FMODE_READ|FMODE_WRITE)) {
643 		if (bdev_check_media_change(bdev) && fs->disk_in)
644 			fs->ejected = 0;
645 		if ((mode & FMODE_WRITE) && fs->write_protected) {
646 			err = -EROFS;
647 			goto out;
648 		}
649 	}
650 	return 0;
651 out:
652 	if (fs->ref_count < 0)
653 		fs->ref_count = 0;
654 	else if (fs->ref_count > 0)
655 		--fs->ref_count;
656 
657 	if (fs->ref_count == 0)
658 		swim_motor(base, OFF);
659 	return err;
660 }
661 
662 static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
663 {
664 	int ret;
665 
666 	mutex_lock(&swim_mutex);
667 	ret = floppy_open(bdev, mode);
668 	mutex_unlock(&swim_mutex);
669 
670 	return ret;
671 }
672 
673 static void floppy_release(struct gendisk *disk, fmode_t mode)
674 {
675 	struct floppy_state *fs = disk->private_data;
676 	struct swim __iomem *base = fs->swd->base;
677 
678 	mutex_lock(&swim_mutex);
679 	if (fs->ref_count < 0)
680 		fs->ref_count = 0;
681 	else if (fs->ref_count > 0)
682 		--fs->ref_count;
683 
684 	if (fs->ref_count == 0)
685 		swim_motor(base, OFF);
686 	mutex_unlock(&swim_mutex);
687 }
688 
689 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
690 			unsigned int cmd, unsigned long param)
691 {
692 	struct floppy_state *fs = bdev->bd_disk->private_data;
693 	int err;
694 
695 	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
696 			return -EPERM;
697 
698 	switch (cmd) {
699 	case FDEJECT:
700 		if (fs->ref_count != 1)
701 			return -EBUSY;
702 		mutex_lock(&swim_mutex);
703 		err = floppy_eject(fs);
704 		mutex_unlock(&swim_mutex);
705 		return err;
706 
707 	case FDGETPRM:
708 		if (copy_to_user((void __user *) param, (void *) &floppy_type,
709 				 sizeof(struct floppy_struct)))
710 			return -EFAULT;
711 		return 0;
712 	}
713 	return -ENOTTY;
714 }
715 
716 static int floppy_getgeo(struct block_device *bdev, struct hd_geometry *geo)
717 {
718 	struct floppy_state *fs = bdev->bd_disk->private_data;
719 	struct floppy_struct *g;
720 	int ret;
721 
722 	ret = get_floppy_geometry(fs, 0, &g);
723 	if (ret)
724 		return ret;
725 
726 	geo->heads = g->head;
727 	geo->sectors = g->sect;
728 	geo->cylinders = g->track;
729 
730 	return 0;
731 }
732 
733 static unsigned int floppy_check_events(struct gendisk *disk,
734 					unsigned int clearing)
735 {
736 	struct floppy_state *fs = disk->private_data;
737 
738 	return fs->ejected ? DISK_EVENT_MEDIA_CHANGE : 0;
739 }
740 
741 static const struct block_device_operations floppy_fops = {
742 	.owner		 = THIS_MODULE,
743 	.open		 = floppy_unlocked_open,
744 	.release	 = floppy_release,
745 	.ioctl		 = floppy_ioctl,
746 	.getgeo		 = floppy_getgeo,
747 	.check_events	 = floppy_check_events,
748 };
749 
750 static int swim_add_floppy(struct swim_priv *swd, enum drive_location location)
751 {
752 	struct floppy_state *fs = &swd->unit[swd->floppy_count];
753 	struct swim __iomem *base = swd->base;
754 
755 	fs->location = location;
756 
757 	swim_drive(base, location);
758 
759 	swim_motor(base, OFF);
760 
761 	fs->type = HD_MEDIA;
762 	fs->head_number = 2;
763 
764 	fs->ref_count = 0;
765 	fs->ejected = 1;
766 
767 	swd->floppy_count++;
768 
769 	return 0;
770 }
771 
772 static const struct blk_mq_ops swim_mq_ops = {
773 	.queue_rq = swim_queue_rq,
774 };
775 
776 static void swim_cleanup_floppy_disk(struct floppy_state *fs)
777 {
778 	struct gendisk *disk = fs->disk;
779 
780 	if (!disk)
781 		return;
782 
783 	if (fs->registered)
784 		del_gendisk(fs->disk);
785 
786 	put_disk(disk);
787 	blk_mq_free_tag_set(&fs->tag_set);
788 }
789 
790 static int swim_floppy_init(struct swim_priv *swd)
791 {
792 	int err;
793 	int drive;
794 	struct swim __iomem *base = swd->base;
795 
796 	/* scan floppy drives */
797 
798 	swim_drive(base, INTERNAL_DRIVE);
799 	if (swim_readbit(base, DRIVE_PRESENT) &&
800 	    !swim_readbit(base, ONEMEG_DRIVE))
801 		swim_add_floppy(swd, INTERNAL_DRIVE);
802 	swim_drive(base, EXTERNAL_DRIVE);
803 	if (swim_readbit(base, DRIVE_PRESENT) &&
804 	    !swim_readbit(base, ONEMEG_DRIVE))
805 		swim_add_floppy(swd, EXTERNAL_DRIVE);
806 
807 	/* register floppy drives */
808 
809 	err = register_blkdev(FLOPPY_MAJOR, "fd");
810 	if (err) {
811 		printk(KERN_ERR "Unable to get major %d for SWIM floppy\n",
812 		       FLOPPY_MAJOR);
813 		return -EBUSY;
814 	}
815 
816 	spin_lock_init(&swd->lock);
817 
818 	for (drive = 0; drive < swd->floppy_count; drive++) {
819 		err = blk_mq_alloc_sq_tag_set(&swd->unit[drive].tag_set,
820 				&swim_mq_ops, 2, BLK_MQ_F_SHOULD_MERGE);
821 		if (err)
822 			goto exit_put_disks;
823 
824 		swd->unit[drive].disk =
825 			blk_mq_alloc_disk(&swd->unit[drive].tag_set,
826 					  &swd->unit[drive]);
827 		if (IS_ERR(swd->unit[drive].disk)) {
828 			blk_mq_free_tag_set(&swd->unit[drive].tag_set);
829 			err = PTR_ERR(swd->unit[drive].disk);
830 			goto exit_put_disks;
831 		}
832 
833 		swd->unit[drive].swd = swd;
834 	}
835 
836 	for (drive = 0; drive < swd->floppy_count; drive++) {
837 		swd->unit[drive].disk->flags = GENHD_FL_REMOVABLE;
838 		swd->unit[drive].disk->major = FLOPPY_MAJOR;
839 		swd->unit[drive].disk->first_minor = drive;
840 		swd->unit[drive].disk->minors = 1;
841 		sprintf(swd->unit[drive].disk->disk_name, "fd%d", drive);
842 		swd->unit[drive].disk->fops = &floppy_fops;
843 		swd->unit[drive].disk->flags |= GENHD_FL_NO_PART;
844 		swd->unit[drive].disk->events = DISK_EVENT_MEDIA_CHANGE;
845 		swd->unit[drive].disk->private_data = &swd->unit[drive];
846 		set_capacity(swd->unit[drive].disk, 2880);
847 		err = add_disk(swd->unit[drive].disk);
848 		if (err)
849 			goto exit_put_disks;
850 		swd->unit[drive].registered = true;
851 	}
852 
853 	return 0;
854 
855 exit_put_disks:
856 	unregister_blkdev(FLOPPY_MAJOR, "fd");
857 	do {
858 		swim_cleanup_floppy_disk(&swd->unit[drive]);
859 	} while (drive--);
860 	return err;
861 }
862 
863 static int swim_probe(struct platform_device *dev)
864 {
865 	struct resource *res;
866 	struct swim __iomem *swim_base;
867 	struct swim_priv *swd;
868 	int ret;
869 
870 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
871 	if (!res) {
872 		ret = -ENODEV;
873 		goto out;
874 	}
875 
876 	if (!request_mem_region(res->start, resource_size(res), CARDNAME)) {
877 		ret = -EBUSY;
878 		goto out;
879 	}
880 
881 	swim_base = (struct swim __iomem *)res->start;
882 	if (!swim_base) {
883 		ret = -ENOMEM;
884 		goto out_release_io;
885 	}
886 
887 	/* probe device */
888 
889 	set_swim_mode(swim_base, 1);
890 	if (!get_swim_mode(swim_base)) {
891 		printk(KERN_INFO "SWIM device not found !\n");
892 		ret = -ENODEV;
893 		goto out_release_io;
894 	}
895 
896 	/* set platform driver data */
897 
898 	swd = kzalloc(sizeof(struct swim_priv), GFP_KERNEL);
899 	if (!swd) {
900 		ret = -ENOMEM;
901 		goto out_release_io;
902 	}
903 	platform_set_drvdata(dev, swd);
904 
905 	swd->base = swim_base;
906 
907 	ret = swim_floppy_init(swd);
908 	if (ret)
909 		goto out_kfree;
910 
911 	return 0;
912 
913 out_kfree:
914 	kfree(swd);
915 out_release_io:
916 	release_mem_region(res->start, resource_size(res));
917 out:
918 	return ret;
919 }
920 
921 static int swim_remove(struct platform_device *dev)
922 {
923 	struct swim_priv *swd = platform_get_drvdata(dev);
924 	int drive;
925 	struct resource *res;
926 
927 	for (drive = 0; drive < swd->floppy_count; drive++)
928 		swim_cleanup_floppy_disk(&swd->unit[drive]);
929 
930 	unregister_blkdev(FLOPPY_MAJOR, "fd");
931 
932 	/* eject floppies */
933 
934 	for (drive = 0; drive < swd->floppy_count; drive++)
935 		floppy_eject(&swd->unit[drive]);
936 
937 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
938 	if (res)
939 		release_mem_region(res->start, resource_size(res));
940 
941 	kfree(swd);
942 
943 	return 0;
944 }
945 
946 static struct platform_driver swim_driver = {
947 	.probe  = swim_probe,
948 	.remove = swim_remove,
949 	.driver   = {
950 		.name	= CARDNAME,
951 	},
952 };
953 
954 static int __init swim_init(void)
955 {
956 	printk(KERN_INFO "SWIM floppy driver %s\n", DRIVER_VERSION);
957 
958 	return platform_driver_register(&swim_driver);
959 }
960 module_init(swim_init);
961 
962 static void __exit swim_exit(void)
963 {
964 	platform_driver_unregister(&swim_driver);
965 }
966 module_exit(swim_exit);
967 
968 MODULE_DESCRIPTION("Driver for SWIM floppy controller");
969 MODULE_LICENSE("GPL");
970 MODULE_AUTHOR("Laurent Vivier <laurent@lvivier.info>");
971 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
972