xref: /openbmc/linux/drivers/usb/storage/datafab.c (revision b627b4ed)
1 /* Driver for Datafab USB Compact Flash reader
2  *
3  * datafab driver v0.1:
4  *
5  * First release
6  *
7  * Current development and maintenance by:
8  *   (c) 2000 Jimmie Mayfield (mayfield+datafab@sackheads.org)
9  *
10  *   Many thanks to Robert Baruch for the SanDisk SmartMedia reader driver
11  *   which I used as a template for this driver.
12  *
13  *   Some bugfixes and scatter-gather code by Gregory P. Smith
14  *   (greg-usb@electricrain.com)
15  *
16  *   Fix for media change by Joerg Schneider (js@joergschneider.com)
17  *
18  * Other contributors:
19  *   (c) 2002 Alan Stern <stern@rowland.org>
20  *
21  * This program is free software; you can redistribute it and/or modify it
22  * under the terms of the GNU General Public License as published by the
23  * Free Software Foundation; either version 2, or (at your option) any
24  * later version.
25  *
26  * This program is distributed in the hope that it will be useful, but
27  * WITHOUT ANY WARRANTY; without even the implied warranty of
28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
29  * General Public License for more details.
30  *
31  * You should have received a copy of the GNU General Public License along
32  * with this program; if not, write to the Free Software Foundation, Inc.,
33  * 675 Mass Ave, Cambridge, MA 02139, USA.
34  */
35 
36 /*
37  * This driver attempts to support USB CompactFlash reader/writer devices
38  * based on Datafab USB-to-ATA chips.  It was specifically developed for the
39  * Datafab MDCFE-B USB CompactFlash reader but has since been found to work
40  * with a variety of Datafab-based devices from a number of manufacturers.
41  * I've received a report of this driver working with a Datafab-based
42  * SmartMedia device though please be aware that I'm personally unable to
43  * test SmartMedia support.
44  *
45  * This driver supports reading and writing.  If you're truly paranoid,
46  * however, you can force the driver into a write-protected state by setting
47  * the WP enable bits in datafab_handle_mode_sense().  See the comments
48  * in that routine.
49  */
50 
51 #include <linux/errno.h>
52 #include <linux/module.h>
53 #include <linux/slab.h>
54 
55 #include <scsi/scsi.h>
56 #include <scsi/scsi_cmnd.h>
57 
58 #include "usb.h"
59 #include "transport.h"
60 #include "protocol.h"
61 #include "debug.h"
62 
63 MODULE_DESCRIPTION("Driver for Datafab USB Compact Flash reader");
64 MODULE_AUTHOR("Jimmie Mayfield <mayfield+datafab@sackheads.org>");
65 MODULE_LICENSE("GPL");
66 
67 struct datafab_info {
68 	unsigned long   sectors;	/* total sector count */
69 	unsigned long   ssize;		/* sector size in bytes */
70 	signed char	lun;		/* used for dual-slot readers */
71 
72 	/* the following aren't used yet */
73 	unsigned char   sense_key;
74 	unsigned long   sense_asc;	/* additional sense code */
75 	unsigned long   sense_ascq;	/* additional sense code qualifier */
76 };
77 
78 static int datafab_determine_lun(struct us_data *us,
79 				 struct datafab_info *info);
80 
81 
82 /*
83  * The table of devices
84  */
85 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
86 		    vendorName, productName, useProtocol, useTransport, \
87 		    initFunction, flags) \
88 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
89   .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }
90 
91 struct usb_device_id datafab_usb_ids[] = {
92 #	include "unusual_datafab.h"
93 	{ }		/* Terminating entry */
94 };
95 MODULE_DEVICE_TABLE(usb, datafab_usb_ids);
96 
97 #undef UNUSUAL_DEV
98 
99 /*
100  * The flags table
101  */
102 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
103 		    vendor_name, product_name, use_protocol, use_transport, \
104 		    init_function, Flags) \
105 { \
106 	.vendorName = vendor_name,	\
107 	.productName = product_name,	\
108 	.useProtocol = use_protocol,	\
109 	.useTransport = use_transport,	\
110 	.initFunction = init_function,	\
111 }
112 
113 static struct us_unusual_dev datafab_unusual_dev_list[] = {
114 #	include "unusual_datafab.h"
115 	{ }		/* Terminating entry */
116 };
117 
118 #undef UNUSUAL_DEV
119 
120 
121 static inline int
122 datafab_bulk_read(struct us_data *us, unsigned char *data, unsigned int len) {
123 	if (len == 0)
124 		return USB_STOR_XFER_GOOD;
125 
126 	US_DEBUGP("datafab_bulk_read:  len = %d\n", len);
127 	return usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
128 			data, len, NULL);
129 }
130 
131 
132 static inline int
133 datafab_bulk_write(struct us_data *us, unsigned char *data, unsigned int len) {
134 	if (len == 0)
135 		return USB_STOR_XFER_GOOD;
136 
137 	US_DEBUGP("datafab_bulk_write:  len = %d\n", len);
138 	return usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
139 			data, len, NULL);
140 }
141 
142 
143 static int datafab_read_data(struct us_data *us,
144 			     struct datafab_info *info,
145 			     u32 sector,
146 			     u32 sectors)
147 {
148 	unsigned char *command = us->iobuf;
149 	unsigned char *buffer;
150 	unsigned char  thistime;
151 	unsigned int totallen, alloclen;
152 	int len, result;
153 	unsigned int sg_offset = 0;
154 	struct scatterlist *sg = NULL;
155 
156 	// we're working in LBA mode.  according to the ATA spec,
157 	// we can support up to 28-bit addressing.  I don't know if Datafab
158 	// supports beyond 24-bit addressing.  It's kind of hard to test
159 	// since it requires > 8GB CF card.
160 	//
161 	if (sectors > 0x0FFFFFFF)
162 		return USB_STOR_TRANSPORT_ERROR;
163 
164 	if (info->lun == -1) {
165 		result = datafab_determine_lun(us, info);
166 		if (result != USB_STOR_TRANSPORT_GOOD)
167 			return result;
168 	}
169 
170 	totallen = sectors * info->ssize;
171 
172 	// Since we don't read more than 64 KB at a time, we have to create
173 	// a bounce buffer and move the data a piece at a time between the
174 	// bounce buffer and the actual transfer buffer.
175 
176 	alloclen = min(totallen, 65536u);
177 	buffer = kmalloc(alloclen, GFP_NOIO);
178 	if (buffer == NULL)
179 		return USB_STOR_TRANSPORT_ERROR;
180 
181 	do {
182 		// loop, never allocate or transfer more than 64k at once
183 		// (min(128k, 255*info->ssize) is the real limit)
184 
185 		len = min(totallen, alloclen);
186 		thistime = (len / info->ssize) & 0xff;
187 
188 		command[0] = 0;
189 		command[1] = thistime;
190 		command[2] = sector & 0xFF;
191 		command[3] = (sector >> 8) & 0xFF;
192 		command[4] = (sector >> 16) & 0xFF;
193 
194 		command[5] = 0xE0 + (info->lun << 4);
195 		command[5] |= (sector >> 24) & 0x0F;
196 		command[6] = 0x20;
197 		command[7] = 0x01;
198 
199 		// send the read command
200 		result = datafab_bulk_write(us, command, 8);
201 		if (result != USB_STOR_XFER_GOOD)
202 			goto leave;
203 
204 		// read the result
205 		result = datafab_bulk_read(us, buffer, len);
206 		if (result != USB_STOR_XFER_GOOD)
207 			goto leave;
208 
209 		// Store the data in the transfer buffer
210 		usb_stor_access_xfer_buf(buffer, len, us->srb,
211 				 &sg, &sg_offset, TO_XFER_BUF);
212 
213 		sector += thistime;
214 		totallen -= len;
215 	} while (totallen > 0);
216 
217 	kfree(buffer);
218 	return USB_STOR_TRANSPORT_GOOD;
219 
220  leave:
221 	kfree(buffer);
222 	return USB_STOR_TRANSPORT_ERROR;
223 }
224 
225 
226 static int datafab_write_data(struct us_data *us,
227 			      struct datafab_info *info,
228 			      u32 sector,
229 			      u32 sectors)
230 {
231 	unsigned char *command = us->iobuf;
232 	unsigned char *reply = us->iobuf;
233 	unsigned char *buffer;
234 	unsigned char thistime;
235 	unsigned int totallen, alloclen;
236 	int len, result;
237 	unsigned int sg_offset = 0;
238 	struct scatterlist *sg = NULL;
239 
240 	// we're working in LBA mode.  according to the ATA spec,
241 	// we can support up to 28-bit addressing.  I don't know if Datafab
242 	// supports beyond 24-bit addressing.  It's kind of hard to test
243 	// since it requires > 8GB CF card.
244 	//
245 	if (sectors > 0x0FFFFFFF)
246 		return USB_STOR_TRANSPORT_ERROR;
247 
248 	if (info->lun == -1) {
249 		result = datafab_determine_lun(us, info);
250 		if (result != USB_STOR_TRANSPORT_GOOD)
251 			return result;
252 	}
253 
254 	totallen = sectors * info->ssize;
255 
256 	// Since we don't write more than 64 KB at a time, we have to create
257 	// a bounce buffer and move the data a piece at a time between the
258 	// bounce buffer and the actual transfer buffer.
259 
260 	alloclen = min(totallen, 65536u);
261 	buffer = kmalloc(alloclen, GFP_NOIO);
262 	if (buffer == NULL)
263 		return USB_STOR_TRANSPORT_ERROR;
264 
265 	do {
266 		// loop, never allocate or transfer more than 64k at once
267 		// (min(128k, 255*info->ssize) is the real limit)
268 
269 		len = min(totallen, alloclen);
270 		thistime = (len / info->ssize) & 0xff;
271 
272 		// Get the data from the transfer buffer
273 		usb_stor_access_xfer_buf(buffer, len, us->srb,
274 				&sg, &sg_offset, FROM_XFER_BUF);
275 
276 		command[0] = 0;
277 		command[1] = thistime;
278 		command[2] = sector & 0xFF;
279 		command[3] = (sector >> 8) & 0xFF;
280 		command[4] = (sector >> 16) & 0xFF;
281 
282 		command[5] = 0xE0 + (info->lun << 4);
283 		command[5] |= (sector >> 24) & 0x0F;
284 		command[6] = 0x30;
285 		command[7] = 0x02;
286 
287 		// send the command
288 		result = datafab_bulk_write(us, command, 8);
289 		if (result != USB_STOR_XFER_GOOD)
290 			goto leave;
291 
292 		// send the data
293 		result = datafab_bulk_write(us, buffer, len);
294 		if (result != USB_STOR_XFER_GOOD)
295 			goto leave;
296 
297 		// read the result
298 		result = datafab_bulk_read(us, reply, 2);
299 		if (result != USB_STOR_XFER_GOOD)
300 			goto leave;
301 
302 		if (reply[0] != 0x50 && reply[1] != 0) {
303 			US_DEBUGP("datafab_write_data:  Gah! "
304 				  "write return code: %02x %02x\n",
305 				  reply[0], reply[1]);
306 			result = USB_STOR_TRANSPORT_ERROR;
307 			goto leave;
308 		}
309 
310 		sector += thistime;
311 		totallen -= len;
312 	} while (totallen > 0);
313 
314 	kfree(buffer);
315 	return USB_STOR_TRANSPORT_GOOD;
316 
317  leave:
318 	kfree(buffer);
319 	return USB_STOR_TRANSPORT_ERROR;
320 }
321 
322 
323 static int datafab_determine_lun(struct us_data *us,
324 				 struct datafab_info *info)
325 {
326 	// Dual-slot readers can be thought of as dual-LUN devices.
327 	// We need to determine which card slot is being used.
328 	// We'll send an IDENTIFY DEVICE command and see which LUN responds...
329 	//
330 	// There might be a better way of doing this?
331 
332 	static unsigned char scommand[8] = { 0, 1, 0, 0, 0, 0xa0, 0xec, 1 };
333 	unsigned char *command = us->iobuf;
334 	unsigned char *buf;
335 	int count = 0, rc;
336 
337 	if (!us || !info)
338 		return USB_STOR_TRANSPORT_ERROR;
339 
340 	memcpy(command, scommand, 8);
341 	buf = kmalloc(512, GFP_NOIO);
342 	if (!buf)
343 		return USB_STOR_TRANSPORT_ERROR;
344 
345 	US_DEBUGP("datafab_determine_lun:  locating...\n");
346 
347 	// we'll try 3 times before giving up...
348 	//
349 	while (count++ < 3) {
350 		command[5] = 0xa0;
351 
352 		rc = datafab_bulk_write(us, command, 8);
353 		if (rc != USB_STOR_XFER_GOOD) {
354 			rc = USB_STOR_TRANSPORT_ERROR;
355 			goto leave;
356 		}
357 
358 		rc = datafab_bulk_read(us, buf, 512);
359 		if (rc == USB_STOR_XFER_GOOD) {
360 			info->lun = 0;
361 			rc = USB_STOR_TRANSPORT_GOOD;
362 			goto leave;
363 		}
364 
365 		command[5] = 0xb0;
366 
367 		rc = datafab_bulk_write(us, command, 8);
368 		if (rc != USB_STOR_XFER_GOOD) {
369 			rc = USB_STOR_TRANSPORT_ERROR;
370 			goto leave;
371 		}
372 
373 		rc = datafab_bulk_read(us, buf, 512);
374 		if (rc == USB_STOR_XFER_GOOD) {
375 			info->lun = 1;
376 			rc = USB_STOR_TRANSPORT_GOOD;
377 			goto leave;
378 		}
379 
380 		msleep(20);
381 	}
382 
383 	rc = USB_STOR_TRANSPORT_ERROR;
384 
385  leave:
386 	kfree(buf);
387 	return rc;
388 }
389 
390 static int datafab_id_device(struct us_data *us,
391 			     struct datafab_info *info)
392 {
393 	// this is a variation of the ATA "IDENTIFY DEVICE" command...according
394 	// to the ATA spec, 'Sector Count' isn't used but the Windows driver
395 	// sets this bit so we do too...
396 	//
397 	static unsigned char scommand[8] = { 0, 1, 0, 0, 0, 0xa0, 0xec, 1 };
398 	unsigned char *command = us->iobuf;
399 	unsigned char *reply;
400 	int rc;
401 
402 	if (!us || !info)
403 		return USB_STOR_TRANSPORT_ERROR;
404 
405 	if (info->lun == -1) {
406 		rc = datafab_determine_lun(us, info);
407 		if (rc != USB_STOR_TRANSPORT_GOOD)
408 			return rc;
409 	}
410 
411 	memcpy(command, scommand, 8);
412 	reply = kmalloc(512, GFP_NOIO);
413 	if (!reply)
414 		return USB_STOR_TRANSPORT_ERROR;
415 
416 	command[5] += (info->lun << 4);
417 
418 	rc = datafab_bulk_write(us, command, 8);
419 	if (rc != USB_STOR_XFER_GOOD) {
420 		rc = USB_STOR_TRANSPORT_ERROR;
421 		goto leave;
422 	}
423 
424 	// we'll go ahead and extract the media capacity while we're here...
425 	//
426 	rc = datafab_bulk_read(us, reply, 512);
427 	if (rc == USB_STOR_XFER_GOOD) {
428 		// capacity is at word offset 57-58
429 		//
430 		info->sectors = ((u32)(reply[117]) << 24) |
431 				((u32)(reply[116]) << 16) |
432 				((u32)(reply[115]) <<  8) |
433 				((u32)(reply[114])      );
434 		rc = USB_STOR_TRANSPORT_GOOD;
435 		goto leave;
436 	}
437 
438 	rc = USB_STOR_TRANSPORT_ERROR;
439 
440  leave:
441 	kfree(reply);
442 	return rc;
443 }
444 
445 
446 static int datafab_handle_mode_sense(struct us_data *us,
447 				     struct scsi_cmnd * srb,
448 				     int sense_6)
449 {
450 	static unsigned char rw_err_page[12] = {
451 		0x1, 0xA, 0x21, 1, 0, 0, 0, 0, 1, 0, 0, 0
452 	};
453 	static unsigned char cache_page[12] = {
454 		0x8, 0xA, 0x1, 0, 0, 0, 0, 0, 0, 0, 0, 0
455 	};
456 	static unsigned char rbac_page[12] = {
457 		0x1B, 0xA, 0, 0x81, 0, 0, 0, 0, 0, 0, 0, 0
458 	};
459 	static unsigned char timer_page[8] = {
460 		0x1C, 0x6, 0, 0, 0, 0
461 	};
462 	unsigned char pc, page_code;
463 	unsigned int i = 0;
464 	struct datafab_info *info = (struct datafab_info *) (us->extra);
465 	unsigned char *ptr = us->iobuf;
466 
467 	// most of this stuff is just a hack to get things working.  the
468 	// datafab reader doesn't present a SCSI interface so we
469 	// fudge the SCSI commands...
470 	//
471 
472 	pc = srb->cmnd[2] >> 6;
473 	page_code = srb->cmnd[2] & 0x3F;
474 
475 	switch (pc) {
476 	   case 0x0:
477 		US_DEBUGP("datafab_handle_mode_sense:  Current values\n");
478 		break;
479 	   case 0x1:
480 		US_DEBUGP("datafab_handle_mode_sense:  Changeable values\n");
481 		break;
482 	   case 0x2:
483 		US_DEBUGP("datafab_handle_mode_sense:  Default values\n");
484 		break;
485 	   case 0x3:
486 		US_DEBUGP("datafab_handle_mode_sense:  Saves values\n");
487 		break;
488 	}
489 
490 	memset(ptr, 0, 8);
491 	if (sense_6) {
492 		ptr[2] = 0x00;		// WP enable: 0x80
493 		i = 4;
494 	} else {
495 		ptr[3] = 0x00;		// WP enable: 0x80
496 		i = 8;
497 	}
498 
499 	switch (page_code) {
500 	   default:
501 		// vendor-specific mode
502 		info->sense_key = 0x05;
503 		info->sense_asc = 0x24;
504 		info->sense_ascq = 0x00;
505 		return USB_STOR_TRANSPORT_FAILED;
506 
507 	   case 0x1:
508 		memcpy(ptr + i, rw_err_page, sizeof(rw_err_page));
509 		i += sizeof(rw_err_page);
510 		break;
511 
512 	   case 0x8:
513 		memcpy(ptr + i, cache_page, sizeof(cache_page));
514 		i += sizeof(cache_page);
515 		break;
516 
517 	   case 0x1B:
518 		memcpy(ptr + i, rbac_page, sizeof(rbac_page));
519 		i += sizeof(rbac_page);
520 		break;
521 
522 	   case 0x1C:
523 		memcpy(ptr + i, timer_page, sizeof(timer_page));
524 		i += sizeof(timer_page);
525 		break;
526 
527 	   case 0x3F:		// retrieve all pages
528 		memcpy(ptr + i, timer_page, sizeof(timer_page));
529 		i += sizeof(timer_page);
530 		memcpy(ptr + i, rbac_page, sizeof(rbac_page));
531 		i += sizeof(rbac_page);
532 		memcpy(ptr + i, cache_page, sizeof(cache_page));
533 		i += sizeof(cache_page);
534 		memcpy(ptr + i, rw_err_page, sizeof(rw_err_page));
535 		i += sizeof(rw_err_page);
536 		break;
537 	}
538 
539 	if (sense_6)
540 		ptr[0] = i - 1;
541 	else
542 		((__be16 *) ptr)[0] = cpu_to_be16(i - 2);
543 	usb_stor_set_xfer_buf(ptr, i, srb);
544 
545 	return USB_STOR_TRANSPORT_GOOD;
546 }
547 
548 static void datafab_info_destructor(void *extra)
549 {
550 	// this routine is a placeholder...
551 	// currently, we don't allocate any extra memory so we're okay
552 }
553 
554 
555 // Transport for the Datafab MDCFE-B
556 //
557 static int datafab_transport(struct scsi_cmnd *srb, struct us_data *us)
558 {
559 	struct datafab_info *info;
560 	int rc;
561 	unsigned long block, blocks;
562 	unsigned char *ptr = us->iobuf;
563 	static unsigned char inquiry_reply[8] = {
564 		0x00, 0x80, 0x00, 0x01, 0x1F, 0x00, 0x00, 0x00
565 	};
566 
567 	if (!us->extra) {
568 		us->extra = kzalloc(sizeof(struct datafab_info), GFP_NOIO);
569 		if (!us->extra) {
570 			US_DEBUGP("datafab_transport:  Gah! "
571 				  "Can't allocate storage for Datafab info struct!\n");
572 			return USB_STOR_TRANSPORT_ERROR;
573 		}
574 		us->extra_destructor = datafab_info_destructor;
575   		((struct datafab_info *)us->extra)->lun = -1;
576 	}
577 
578 	info = (struct datafab_info *) (us->extra);
579 
580 	if (srb->cmnd[0] == INQUIRY) {
581 		US_DEBUGP("datafab_transport:  INQUIRY.  Returning bogus response");
582 		memcpy(ptr, inquiry_reply, sizeof(inquiry_reply));
583 		fill_inquiry_response(us, ptr, 36);
584 		return USB_STOR_TRANSPORT_GOOD;
585 	}
586 
587 	if (srb->cmnd[0] == READ_CAPACITY) {
588 		info->ssize = 0x200;  // hard coded 512 byte sectors as per ATA spec
589 		rc = datafab_id_device(us, info);
590 		if (rc != USB_STOR_TRANSPORT_GOOD)
591 			return rc;
592 
593 		US_DEBUGP("datafab_transport:  READ_CAPACITY:  %ld sectors, %ld bytes per sector\n",
594 			  info->sectors, info->ssize);
595 
596 		// build the reply
597 		// we need the last sector, not the number of sectors
598 		((__be32 *) ptr)[0] = cpu_to_be32(info->sectors - 1);
599 		((__be32 *) ptr)[1] = cpu_to_be32(info->ssize);
600 		usb_stor_set_xfer_buf(ptr, 8, srb);
601 
602 		return USB_STOR_TRANSPORT_GOOD;
603 	}
604 
605 	if (srb->cmnd[0] == MODE_SELECT_10) {
606 		US_DEBUGP("datafab_transport:  Gah! MODE_SELECT_10.\n");
607 		return USB_STOR_TRANSPORT_ERROR;
608 	}
609 
610 	// don't bother implementing READ_6 or WRITE_6.
611 	//
612 	if (srb->cmnd[0] == READ_10) {
613 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
614 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
615 
616 		blocks = ((u32)(srb->cmnd[7]) << 8) | ((u32)(srb->cmnd[8]));
617 
618 		US_DEBUGP("datafab_transport:  READ_10: read block 0x%04lx  count %ld\n", block, blocks);
619 		return datafab_read_data(us, info, block, blocks);
620 	}
621 
622 	if (srb->cmnd[0] == READ_12) {
623 		// we'll probably never see a READ_12 but we'll do it anyway...
624 		//
625 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
626 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
627 
628 		blocks = ((u32)(srb->cmnd[6]) << 24) | ((u32)(srb->cmnd[7]) << 16) |
629 			 ((u32)(srb->cmnd[8]) <<  8) | ((u32)(srb->cmnd[9]));
630 
631 		US_DEBUGP("datafab_transport:  READ_12: read block 0x%04lx  count %ld\n", block, blocks);
632 		return datafab_read_data(us, info, block, blocks);
633 	}
634 
635 	if (srb->cmnd[0] == WRITE_10) {
636 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
637 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
638 
639 		blocks = ((u32)(srb->cmnd[7]) << 8) | ((u32)(srb->cmnd[8]));
640 
641 		US_DEBUGP("datafab_transport:  WRITE_10: write block 0x%04lx  count %ld\n", block, blocks);
642 		return datafab_write_data(us, info, block, blocks);
643 	}
644 
645 	if (srb->cmnd[0] == WRITE_12) {
646 		// we'll probably never see a WRITE_12 but we'll do it anyway...
647 		//
648 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
649 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
650 
651 		blocks = ((u32)(srb->cmnd[6]) << 24) | ((u32)(srb->cmnd[7]) << 16) |
652 			 ((u32)(srb->cmnd[8]) <<  8) | ((u32)(srb->cmnd[9]));
653 
654 		US_DEBUGP("datafab_transport:  WRITE_12: write block 0x%04lx  count %ld\n", block, blocks);
655 		return datafab_write_data(us, info, block, blocks);
656 	}
657 
658 	if (srb->cmnd[0] == TEST_UNIT_READY) {
659 		US_DEBUGP("datafab_transport:  TEST_UNIT_READY.\n");
660 		return datafab_id_device(us, info);
661 	}
662 
663 	if (srb->cmnd[0] == REQUEST_SENSE) {
664 		US_DEBUGP("datafab_transport:  REQUEST_SENSE.  Returning faked response\n");
665 
666 		// this response is pretty bogus right now.  eventually if necessary
667 		// we can set the correct sense data.  so far though it hasn't been
668 		// necessary
669 		//
670 		memset(ptr, 0, 18);
671 		ptr[0] = 0xF0;
672 		ptr[2] = info->sense_key;
673 		ptr[7] = 11;
674 		ptr[12] = info->sense_asc;
675 		ptr[13] = info->sense_ascq;
676 		usb_stor_set_xfer_buf(ptr, 18, srb);
677 
678 		return USB_STOR_TRANSPORT_GOOD;
679 	}
680 
681 	if (srb->cmnd[0] == MODE_SENSE) {
682 		US_DEBUGP("datafab_transport:  MODE_SENSE_6 detected\n");
683 		return datafab_handle_mode_sense(us, srb, 1);
684 	}
685 
686 	if (srb->cmnd[0] == MODE_SENSE_10) {
687 		US_DEBUGP("datafab_transport:  MODE_SENSE_10 detected\n");
688 		return datafab_handle_mode_sense(us, srb, 0);
689 	}
690 
691 	if (srb->cmnd[0] == ALLOW_MEDIUM_REMOVAL) {
692 		// sure.  whatever.  not like we can stop the user from
693 		// popping the media out of the device (no locking doors, etc)
694 		//
695 		return USB_STOR_TRANSPORT_GOOD;
696 	}
697 
698 	if (srb->cmnd[0] == START_STOP) {
699 		/* this is used by sd.c'check_scsidisk_media_change to detect
700 		   media change */
701 		US_DEBUGP("datafab_transport:  START_STOP.\n");
702 		/* the first datafab_id_device after a media change returns
703 		   an error (determined experimentally) */
704 		rc = datafab_id_device(us, info);
705 		if (rc == USB_STOR_TRANSPORT_GOOD) {
706 			info->sense_key = NO_SENSE;
707 			srb->result = SUCCESS;
708 		} else {
709 			info->sense_key = UNIT_ATTENTION;
710 			srb->result = SAM_STAT_CHECK_CONDITION;
711 		}
712 		return rc;
713 	}
714 
715 	US_DEBUGP("datafab_transport:  Gah! Unknown command: %d (0x%x)\n",
716 		  srb->cmnd[0], srb->cmnd[0]);
717 	info->sense_key = 0x05;
718 	info->sense_asc = 0x20;
719 	info->sense_ascq = 0x00;
720 	return USB_STOR_TRANSPORT_FAILED;
721 }
722 
723 static int datafab_probe(struct usb_interface *intf,
724 			 const struct usb_device_id *id)
725 {
726 	struct us_data *us;
727 	int result;
728 
729 	result = usb_stor_probe1(&us, intf, id,
730 			(id - datafab_usb_ids) + datafab_unusual_dev_list);
731 	if (result)
732 		return result;
733 
734 	us->transport_name  = "Datafab Bulk-Only";
735 	us->transport = datafab_transport;
736 	us->transport_reset = usb_stor_Bulk_reset;
737 	us->max_lun = 1;
738 
739 	result = usb_stor_probe2(us);
740 	return result;
741 }
742 
743 static struct usb_driver datafab_driver = {
744 	.name =		"ums-datafab",
745 	.probe =	datafab_probe,
746 	.disconnect =	usb_stor_disconnect,
747 	.suspend =	usb_stor_suspend,
748 	.resume =	usb_stor_resume,
749 	.reset_resume =	usb_stor_reset_resume,
750 	.pre_reset =	usb_stor_pre_reset,
751 	.post_reset =	usb_stor_post_reset,
752 	.id_table =	datafab_usb_ids,
753 	.soft_unbind =	1,
754 };
755 
756 static int __init datafab_init(void)
757 {
758 	return usb_register(&datafab_driver);
759 }
760 
761 static void __exit datafab_exit(void)
762 {
763 	usb_deregister(&datafab_driver);
764 }
765 
766 module_init(datafab_init);
767 module_exit(datafab_exit);
768