xref: /openbmc/linux/drivers/usb/storage/datafab.c (revision cfbb9be8)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for Datafab USB Compact Flash reader
4  *
5  * datafab driver v0.1:
6  *
7  * First release
8  *
9  * Current development and maintenance by:
10  *   (c) 2000 Jimmie Mayfield (mayfield+datafab@sackheads.org)
11  *
12  *   Many thanks to Robert Baruch for the SanDisk SmartMedia reader driver
13  *   which I used as a template for this driver.
14  *
15  *   Some bugfixes and scatter-gather code by Gregory P. Smith
16  *   (greg-usb@electricrain.com)
17  *
18  *   Fix for media change by Joerg Schneider (js@joergschneider.com)
19  *
20  * Other contributors:
21  *   (c) 2002 Alan Stern <stern@rowland.org>
22  */
23 
24 /*
25  * This driver attempts to support USB CompactFlash reader/writer devices
26  * based on Datafab USB-to-ATA chips.  It was specifically developed for the
27  * Datafab MDCFE-B USB CompactFlash reader but has since been found to work
28  * with a variety of Datafab-based devices from a number of manufacturers.
29  * I've received a report of this driver working with a Datafab-based
30  * SmartMedia device though please be aware that I'm personally unable to
31  * test SmartMedia support.
32  *
33  * This driver supports reading and writing.  If you're truly paranoid,
34  * however, you can force the driver into a write-protected state by setting
35  * the WP enable bits in datafab_handle_mode_sense().  See the comments
36  * in that routine.
37  */
38 
39 #include <linux/errno.h>
40 #include <linux/module.h>
41 #include <linux/slab.h>
42 
43 #include <scsi/scsi.h>
44 #include <scsi/scsi_cmnd.h>
45 
46 #include "usb.h"
47 #include "transport.h"
48 #include "protocol.h"
49 #include "debug.h"
50 #include "scsiglue.h"
51 
52 #define DRV_NAME "ums-datafab"
53 
54 MODULE_DESCRIPTION("Driver for Datafab USB Compact Flash reader");
55 MODULE_AUTHOR("Jimmie Mayfield <mayfield+datafab@sackheads.org>");
56 MODULE_LICENSE("GPL");
57 
58 struct datafab_info {
59 	unsigned long   sectors;	/* total sector count */
60 	unsigned long   ssize;		/* sector size in bytes */
61 	signed char	lun;		/* used for dual-slot readers */
62 
63 	/* the following aren't used yet */
64 	unsigned char   sense_key;
65 	unsigned long   sense_asc;	/* additional sense code */
66 	unsigned long   sense_ascq;	/* additional sense code qualifier */
67 };
68 
69 static int datafab_determine_lun(struct us_data *us,
70 				 struct datafab_info *info);
71 
72 
73 /*
74  * The table of devices
75  */
76 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
77 		    vendorName, productName, useProtocol, useTransport, \
78 		    initFunction, flags) \
79 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
80   .driver_info = (flags) }
81 
82 static struct usb_device_id datafab_usb_ids[] = {
83 #	include "unusual_datafab.h"
84 	{ }		/* Terminating entry */
85 };
86 MODULE_DEVICE_TABLE(usb, datafab_usb_ids);
87 
88 #undef UNUSUAL_DEV
89 
90 /*
91  * The flags table
92  */
93 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
94 		    vendor_name, product_name, use_protocol, use_transport, \
95 		    init_function, Flags) \
96 { \
97 	.vendorName = vendor_name,	\
98 	.productName = product_name,	\
99 	.useProtocol = use_protocol,	\
100 	.useTransport = use_transport,	\
101 	.initFunction = init_function,	\
102 }
103 
104 static struct us_unusual_dev datafab_unusual_dev_list[] = {
105 #	include "unusual_datafab.h"
106 	{ }		/* Terminating entry */
107 };
108 
109 #undef UNUSUAL_DEV
110 
111 
112 static inline int
113 datafab_bulk_read(struct us_data *us, unsigned char *data, unsigned int len) {
114 	if (len == 0)
115 		return USB_STOR_XFER_GOOD;
116 
117 	usb_stor_dbg(us, "len = %d\n", len);
118 	return usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
119 			data, len, NULL);
120 }
121 
122 
123 static inline int
124 datafab_bulk_write(struct us_data *us, unsigned char *data, unsigned int len) {
125 	if (len == 0)
126 		return USB_STOR_XFER_GOOD;
127 
128 	usb_stor_dbg(us, "len = %d\n", len);
129 	return usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
130 			data, len, NULL);
131 }
132 
133 
134 static int datafab_read_data(struct us_data *us,
135 			     struct datafab_info *info,
136 			     u32 sector,
137 			     u32 sectors)
138 {
139 	unsigned char *command = us->iobuf;
140 	unsigned char *buffer;
141 	unsigned char  thistime;
142 	unsigned int totallen, alloclen;
143 	int len, result;
144 	unsigned int sg_offset = 0;
145 	struct scatterlist *sg = NULL;
146 
147 	// we're working in LBA mode.  according to the ATA spec,
148 	// we can support up to 28-bit addressing.  I don't know if Datafab
149 	// supports beyond 24-bit addressing.  It's kind of hard to test
150 	// since it requires > 8GB CF card.
151 	//
152 	if (sectors > 0x0FFFFFFF)
153 		return USB_STOR_TRANSPORT_ERROR;
154 
155 	if (info->lun == -1) {
156 		result = datafab_determine_lun(us, info);
157 		if (result != USB_STOR_TRANSPORT_GOOD)
158 			return result;
159 	}
160 
161 	totallen = sectors * info->ssize;
162 
163 	// Since we don't read more than 64 KB at a time, we have to create
164 	// a bounce buffer and move the data a piece at a time between the
165 	// bounce buffer and the actual transfer buffer.
166 
167 	alloclen = min(totallen, 65536u);
168 	buffer = kmalloc(alloclen, GFP_NOIO);
169 	if (buffer == NULL)
170 		return USB_STOR_TRANSPORT_ERROR;
171 
172 	do {
173 		// loop, never allocate or transfer more than 64k at once
174 		// (min(128k, 255*info->ssize) is the real limit)
175 
176 		len = min(totallen, alloclen);
177 		thistime = (len / info->ssize) & 0xff;
178 
179 		command[0] = 0;
180 		command[1] = thistime;
181 		command[2] = sector & 0xFF;
182 		command[3] = (sector >> 8) & 0xFF;
183 		command[4] = (sector >> 16) & 0xFF;
184 
185 		command[5] = 0xE0 + (info->lun << 4);
186 		command[5] |= (sector >> 24) & 0x0F;
187 		command[6] = 0x20;
188 		command[7] = 0x01;
189 
190 		// send the read command
191 		result = datafab_bulk_write(us, command, 8);
192 		if (result != USB_STOR_XFER_GOOD)
193 			goto leave;
194 
195 		// read the result
196 		result = datafab_bulk_read(us, buffer, len);
197 		if (result != USB_STOR_XFER_GOOD)
198 			goto leave;
199 
200 		// Store the data in the transfer buffer
201 		usb_stor_access_xfer_buf(buffer, len, us->srb,
202 				 &sg, &sg_offset, TO_XFER_BUF);
203 
204 		sector += thistime;
205 		totallen -= len;
206 	} while (totallen > 0);
207 
208 	kfree(buffer);
209 	return USB_STOR_TRANSPORT_GOOD;
210 
211  leave:
212 	kfree(buffer);
213 	return USB_STOR_TRANSPORT_ERROR;
214 }
215 
216 
217 static int datafab_write_data(struct us_data *us,
218 			      struct datafab_info *info,
219 			      u32 sector,
220 			      u32 sectors)
221 {
222 	unsigned char *command = us->iobuf;
223 	unsigned char *reply = us->iobuf;
224 	unsigned char *buffer;
225 	unsigned char thistime;
226 	unsigned int totallen, alloclen;
227 	int len, result;
228 	unsigned int sg_offset = 0;
229 	struct scatterlist *sg = NULL;
230 
231 	// we're working in LBA mode.  according to the ATA spec,
232 	// we can support up to 28-bit addressing.  I don't know if Datafab
233 	// supports beyond 24-bit addressing.  It's kind of hard to test
234 	// since it requires > 8GB CF card.
235 	//
236 	if (sectors > 0x0FFFFFFF)
237 		return USB_STOR_TRANSPORT_ERROR;
238 
239 	if (info->lun == -1) {
240 		result = datafab_determine_lun(us, info);
241 		if (result != USB_STOR_TRANSPORT_GOOD)
242 			return result;
243 	}
244 
245 	totallen = sectors * info->ssize;
246 
247 	// Since we don't write more than 64 KB at a time, we have to create
248 	// a bounce buffer and move the data a piece at a time between the
249 	// bounce buffer and the actual transfer buffer.
250 
251 	alloclen = min(totallen, 65536u);
252 	buffer = kmalloc(alloclen, GFP_NOIO);
253 	if (buffer == NULL)
254 		return USB_STOR_TRANSPORT_ERROR;
255 
256 	do {
257 		// loop, never allocate or transfer more than 64k at once
258 		// (min(128k, 255*info->ssize) is the real limit)
259 
260 		len = min(totallen, alloclen);
261 		thistime = (len / info->ssize) & 0xff;
262 
263 		// Get the data from the transfer buffer
264 		usb_stor_access_xfer_buf(buffer, len, us->srb,
265 				&sg, &sg_offset, FROM_XFER_BUF);
266 
267 		command[0] = 0;
268 		command[1] = thistime;
269 		command[2] = sector & 0xFF;
270 		command[3] = (sector >> 8) & 0xFF;
271 		command[4] = (sector >> 16) & 0xFF;
272 
273 		command[5] = 0xE0 + (info->lun << 4);
274 		command[5] |= (sector >> 24) & 0x0F;
275 		command[6] = 0x30;
276 		command[7] = 0x02;
277 
278 		// send the command
279 		result = datafab_bulk_write(us, command, 8);
280 		if (result != USB_STOR_XFER_GOOD)
281 			goto leave;
282 
283 		// send the data
284 		result = datafab_bulk_write(us, buffer, len);
285 		if (result != USB_STOR_XFER_GOOD)
286 			goto leave;
287 
288 		// read the result
289 		result = datafab_bulk_read(us, reply, 2);
290 		if (result != USB_STOR_XFER_GOOD)
291 			goto leave;
292 
293 		if (reply[0] != 0x50 && reply[1] != 0) {
294 			usb_stor_dbg(us, "Gah! write return code: %02x %02x\n",
295 				     reply[0], reply[1]);
296 			result = USB_STOR_TRANSPORT_ERROR;
297 			goto leave;
298 		}
299 
300 		sector += thistime;
301 		totallen -= len;
302 	} while (totallen > 0);
303 
304 	kfree(buffer);
305 	return USB_STOR_TRANSPORT_GOOD;
306 
307  leave:
308 	kfree(buffer);
309 	return USB_STOR_TRANSPORT_ERROR;
310 }
311 
312 
313 static int datafab_determine_lun(struct us_data *us,
314 				 struct datafab_info *info)
315 {
316 	// Dual-slot readers can be thought of as dual-LUN devices.
317 	// We need to determine which card slot is being used.
318 	// We'll send an IDENTIFY DEVICE command and see which LUN responds...
319 	//
320 	// There might be a better way of doing this?
321 
322 	static unsigned char scommand[8] = { 0, 1, 0, 0, 0, 0xa0, 0xec, 1 };
323 	unsigned char *command = us->iobuf;
324 	unsigned char *buf;
325 	int count = 0, rc;
326 
327 	if (!info)
328 		return USB_STOR_TRANSPORT_ERROR;
329 
330 	memcpy(command, scommand, 8);
331 	buf = kmalloc(512, GFP_NOIO);
332 	if (!buf)
333 		return USB_STOR_TRANSPORT_ERROR;
334 
335 	usb_stor_dbg(us, "locating...\n");
336 
337 	// we'll try 3 times before giving up...
338 	//
339 	while (count++ < 3) {
340 		command[5] = 0xa0;
341 
342 		rc = datafab_bulk_write(us, command, 8);
343 		if (rc != USB_STOR_XFER_GOOD) {
344 			rc = USB_STOR_TRANSPORT_ERROR;
345 			goto leave;
346 		}
347 
348 		rc = datafab_bulk_read(us, buf, 512);
349 		if (rc == USB_STOR_XFER_GOOD) {
350 			info->lun = 0;
351 			rc = USB_STOR_TRANSPORT_GOOD;
352 			goto leave;
353 		}
354 
355 		command[5] = 0xb0;
356 
357 		rc = datafab_bulk_write(us, command, 8);
358 		if (rc != USB_STOR_XFER_GOOD) {
359 			rc = USB_STOR_TRANSPORT_ERROR;
360 			goto leave;
361 		}
362 
363 		rc = datafab_bulk_read(us, buf, 512);
364 		if (rc == USB_STOR_XFER_GOOD) {
365 			info->lun = 1;
366 			rc = USB_STOR_TRANSPORT_GOOD;
367 			goto leave;
368 		}
369 
370 		msleep(20);
371 	}
372 
373 	rc = USB_STOR_TRANSPORT_ERROR;
374 
375  leave:
376 	kfree(buf);
377 	return rc;
378 }
379 
380 static int datafab_id_device(struct us_data *us,
381 			     struct datafab_info *info)
382 {
383 	// this is a variation of the ATA "IDENTIFY DEVICE" command...according
384 	// to the ATA spec, 'Sector Count' isn't used but the Windows driver
385 	// sets this bit so we do too...
386 	//
387 	static unsigned char scommand[8] = { 0, 1, 0, 0, 0, 0xa0, 0xec, 1 };
388 	unsigned char *command = us->iobuf;
389 	unsigned char *reply;
390 	int rc;
391 
392 	if (!info)
393 		return USB_STOR_TRANSPORT_ERROR;
394 
395 	if (info->lun == -1) {
396 		rc = datafab_determine_lun(us, info);
397 		if (rc != USB_STOR_TRANSPORT_GOOD)
398 			return rc;
399 	}
400 
401 	memcpy(command, scommand, 8);
402 	reply = kmalloc(512, GFP_NOIO);
403 	if (!reply)
404 		return USB_STOR_TRANSPORT_ERROR;
405 
406 	command[5] += (info->lun << 4);
407 
408 	rc = datafab_bulk_write(us, command, 8);
409 	if (rc != USB_STOR_XFER_GOOD) {
410 		rc = USB_STOR_TRANSPORT_ERROR;
411 		goto leave;
412 	}
413 
414 	// we'll go ahead and extract the media capacity while we're here...
415 	//
416 	rc = datafab_bulk_read(us, reply, 512);
417 	if (rc == USB_STOR_XFER_GOOD) {
418 		// capacity is at word offset 57-58
419 		//
420 		info->sectors = ((u32)(reply[117]) << 24) |
421 				((u32)(reply[116]) << 16) |
422 				((u32)(reply[115]) <<  8) |
423 				((u32)(reply[114])      );
424 		rc = USB_STOR_TRANSPORT_GOOD;
425 		goto leave;
426 	}
427 
428 	rc = USB_STOR_TRANSPORT_ERROR;
429 
430  leave:
431 	kfree(reply);
432 	return rc;
433 }
434 
435 
436 static int datafab_handle_mode_sense(struct us_data *us,
437 				     struct scsi_cmnd * srb,
438 				     int sense_6)
439 {
440 	static unsigned char rw_err_page[12] = {
441 		0x1, 0xA, 0x21, 1, 0, 0, 0, 0, 1, 0, 0, 0
442 	};
443 	static unsigned char cache_page[12] = {
444 		0x8, 0xA, 0x1, 0, 0, 0, 0, 0, 0, 0, 0, 0
445 	};
446 	static unsigned char rbac_page[12] = {
447 		0x1B, 0xA, 0, 0x81, 0, 0, 0, 0, 0, 0, 0, 0
448 	};
449 	static unsigned char timer_page[8] = {
450 		0x1C, 0x6, 0, 0, 0, 0
451 	};
452 	unsigned char pc, page_code;
453 	unsigned int i = 0;
454 	struct datafab_info *info = (struct datafab_info *) (us->extra);
455 	unsigned char *ptr = us->iobuf;
456 
457 	// most of this stuff is just a hack to get things working.  the
458 	// datafab reader doesn't present a SCSI interface so we
459 	// fudge the SCSI commands...
460 	//
461 
462 	pc = srb->cmnd[2] >> 6;
463 	page_code = srb->cmnd[2] & 0x3F;
464 
465 	switch (pc) {
466 	   case 0x0:
467 		   usb_stor_dbg(us, "Current values\n");
468 		break;
469 	   case 0x1:
470 		   usb_stor_dbg(us, "Changeable values\n");
471 		break;
472 	   case 0x2:
473 		   usb_stor_dbg(us, "Default values\n");
474 		break;
475 	   case 0x3:
476 		   usb_stor_dbg(us, "Saves values\n");
477 		break;
478 	}
479 
480 	memset(ptr, 0, 8);
481 	if (sense_6) {
482 		ptr[2] = 0x00;		// WP enable: 0x80
483 		i = 4;
484 	} else {
485 		ptr[3] = 0x00;		// WP enable: 0x80
486 		i = 8;
487 	}
488 
489 	switch (page_code) {
490 	   default:
491 		// vendor-specific mode
492 		info->sense_key = 0x05;
493 		info->sense_asc = 0x24;
494 		info->sense_ascq = 0x00;
495 		return USB_STOR_TRANSPORT_FAILED;
496 
497 	   case 0x1:
498 		memcpy(ptr + i, rw_err_page, sizeof(rw_err_page));
499 		i += sizeof(rw_err_page);
500 		break;
501 
502 	   case 0x8:
503 		memcpy(ptr + i, cache_page, sizeof(cache_page));
504 		i += sizeof(cache_page);
505 		break;
506 
507 	   case 0x1B:
508 		memcpy(ptr + i, rbac_page, sizeof(rbac_page));
509 		i += sizeof(rbac_page);
510 		break;
511 
512 	   case 0x1C:
513 		memcpy(ptr + i, timer_page, sizeof(timer_page));
514 		i += sizeof(timer_page);
515 		break;
516 
517 	   case 0x3F:		// retrieve all pages
518 		memcpy(ptr + i, timer_page, sizeof(timer_page));
519 		i += sizeof(timer_page);
520 		memcpy(ptr + i, rbac_page, sizeof(rbac_page));
521 		i += sizeof(rbac_page);
522 		memcpy(ptr + i, cache_page, sizeof(cache_page));
523 		i += sizeof(cache_page);
524 		memcpy(ptr + i, rw_err_page, sizeof(rw_err_page));
525 		i += sizeof(rw_err_page);
526 		break;
527 	}
528 
529 	if (sense_6)
530 		ptr[0] = i - 1;
531 	else
532 		((__be16 *) ptr)[0] = cpu_to_be16(i - 2);
533 	usb_stor_set_xfer_buf(ptr, i, srb);
534 
535 	return USB_STOR_TRANSPORT_GOOD;
536 }
537 
538 static void datafab_info_destructor(void *extra)
539 {
540 	// this routine is a placeholder...
541 	// currently, we don't allocate any extra memory so we're okay
542 }
543 
544 
545 // Transport for the Datafab MDCFE-B
546 //
547 static int datafab_transport(struct scsi_cmnd *srb, struct us_data *us)
548 {
549 	struct datafab_info *info;
550 	int rc;
551 	unsigned long block, blocks;
552 	unsigned char *ptr = us->iobuf;
553 	static unsigned char inquiry_reply[8] = {
554 		0x00, 0x80, 0x00, 0x01, 0x1F, 0x00, 0x00, 0x00
555 	};
556 
557 	if (!us->extra) {
558 		us->extra = kzalloc(sizeof(struct datafab_info), GFP_NOIO);
559 		if (!us->extra)
560 			return USB_STOR_TRANSPORT_ERROR;
561 
562 		us->extra_destructor = datafab_info_destructor;
563   		((struct datafab_info *)us->extra)->lun = -1;
564 	}
565 
566 	info = (struct datafab_info *) (us->extra);
567 
568 	if (srb->cmnd[0] == INQUIRY) {
569 		usb_stor_dbg(us, "INQUIRY - Returning bogus response\n");
570 		memcpy(ptr, inquiry_reply, sizeof(inquiry_reply));
571 		fill_inquiry_response(us, ptr, 36);
572 		return USB_STOR_TRANSPORT_GOOD;
573 	}
574 
575 	if (srb->cmnd[0] == READ_CAPACITY) {
576 		info->ssize = 0x200;  // hard coded 512 byte sectors as per ATA spec
577 		rc = datafab_id_device(us, info);
578 		if (rc != USB_STOR_TRANSPORT_GOOD)
579 			return rc;
580 
581 		usb_stor_dbg(us, "READ_CAPACITY:  %ld sectors, %ld bytes per sector\n",
582 			     info->sectors, info->ssize);
583 
584 		// build the reply
585 		// we need the last sector, not the number of sectors
586 		((__be32 *) ptr)[0] = cpu_to_be32(info->sectors - 1);
587 		((__be32 *) ptr)[1] = cpu_to_be32(info->ssize);
588 		usb_stor_set_xfer_buf(ptr, 8, srb);
589 
590 		return USB_STOR_TRANSPORT_GOOD;
591 	}
592 
593 	if (srb->cmnd[0] == MODE_SELECT_10) {
594 		usb_stor_dbg(us, "Gah! MODE_SELECT_10\n");
595 		return USB_STOR_TRANSPORT_ERROR;
596 	}
597 
598 	// don't bother implementing READ_6 or WRITE_6.
599 	//
600 	if (srb->cmnd[0] == READ_10) {
601 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
602 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
603 
604 		blocks = ((u32)(srb->cmnd[7]) << 8) | ((u32)(srb->cmnd[8]));
605 
606 		usb_stor_dbg(us, "READ_10: read block 0x%04lx  count %ld\n",
607 			     block, blocks);
608 		return datafab_read_data(us, info, block, blocks);
609 	}
610 
611 	if (srb->cmnd[0] == READ_12) {
612 		// we'll probably never see a READ_12 but we'll do it anyway...
613 		//
614 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
615 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
616 
617 		blocks = ((u32)(srb->cmnd[6]) << 24) | ((u32)(srb->cmnd[7]) << 16) |
618 			 ((u32)(srb->cmnd[8]) <<  8) | ((u32)(srb->cmnd[9]));
619 
620 		usb_stor_dbg(us, "READ_12: read block 0x%04lx  count %ld\n",
621 			     block, blocks);
622 		return datafab_read_data(us, info, block, blocks);
623 	}
624 
625 	if (srb->cmnd[0] == WRITE_10) {
626 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
627 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
628 
629 		blocks = ((u32)(srb->cmnd[7]) << 8) | ((u32)(srb->cmnd[8]));
630 
631 		usb_stor_dbg(us, "WRITE_10: write block 0x%04lx count %ld\n",
632 			     block, blocks);
633 		return datafab_write_data(us, info, block, blocks);
634 	}
635 
636 	if (srb->cmnd[0] == WRITE_12) {
637 		// we'll probably never see a WRITE_12 but we'll do it anyway...
638 		//
639 		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
640 			((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));
641 
642 		blocks = ((u32)(srb->cmnd[6]) << 24) | ((u32)(srb->cmnd[7]) << 16) |
643 			 ((u32)(srb->cmnd[8]) <<  8) | ((u32)(srb->cmnd[9]));
644 
645 		usb_stor_dbg(us, "WRITE_12: write block 0x%04lx count %ld\n",
646 			     block, blocks);
647 		return datafab_write_data(us, info, block, blocks);
648 	}
649 
650 	if (srb->cmnd[0] == TEST_UNIT_READY) {
651 		usb_stor_dbg(us, "TEST_UNIT_READY\n");
652 		return datafab_id_device(us, info);
653 	}
654 
655 	if (srb->cmnd[0] == REQUEST_SENSE) {
656 		usb_stor_dbg(us, "REQUEST_SENSE - Returning faked response\n");
657 
658 		// this response is pretty bogus right now.  eventually if necessary
659 		// we can set the correct sense data.  so far though it hasn't been
660 		// necessary
661 		//
662 		memset(ptr, 0, 18);
663 		ptr[0] = 0xF0;
664 		ptr[2] = info->sense_key;
665 		ptr[7] = 11;
666 		ptr[12] = info->sense_asc;
667 		ptr[13] = info->sense_ascq;
668 		usb_stor_set_xfer_buf(ptr, 18, srb);
669 
670 		return USB_STOR_TRANSPORT_GOOD;
671 	}
672 
673 	if (srb->cmnd[0] == MODE_SENSE) {
674 		usb_stor_dbg(us, "MODE_SENSE_6 detected\n");
675 		return datafab_handle_mode_sense(us, srb, 1);
676 	}
677 
678 	if (srb->cmnd[0] == MODE_SENSE_10) {
679 		usb_stor_dbg(us, "MODE_SENSE_10 detected\n");
680 		return datafab_handle_mode_sense(us, srb, 0);
681 	}
682 
683 	if (srb->cmnd[0] == ALLOW_MEDIUM_REMOVAL) {
684 		/*
685 		 * sure.  whatever.  not like we can stop the user from
686 		 * popping the media out of the device (no locking doors, etc)
687 		 */
688 		return USB_STOR_TRANSPORT_GOOD;
689 	}
690 
691 	if (srb->cmnd[0] == START_STOP) {
692 		/*
693 		 * this is used by sd.c'check_scsidisk_media_change to detect
694 		 * media change
695 		 */
696 		usb_stor_dbg(us, "START_STOP\n");
697 		/*
698 		 * the first datafab_id_device after a media change returns
699 		 * an error (determined experimentally)
700 		 */
701 		rc = datafab_id_device(us, info);
702 		if (rc == USB_STOR_TRANSPORT_GOOD) {
703 			info->sense_key = NO_SENSE;
704 			srb->result = SUCCESS;
705 		} else {
706 			info->sense_key = UNIT_ATTENTION;
707 			srb->result = SAM_STAT_CHECK_CONDITION;
708 		}
709 		return rc;
710 	}
711 
712 	usb_stor_dbg(us, "Gah! Unknown command: %d (0x%x)\n",
713 		     srb->cmnd[0], srb->cmnd[0]);
714 	info->sense_key = 0x05;
715 	info->sense_asc = 0x20;
716 	info->sense_ascq = 0x00;
717 	return USB_STOR_TRANSPORT_FAILED;
718 }
719 
720 static struct scsi_host_template datafab_host_template;
721 
722 static int datafab_probe(struct usb_interface *intf,
723 			 const struct usb_device_id *id)
724 {
725 	struct us_data *us;
726 	int result;
727 
728 	result = usb_stor_probe1(&us, intf, id,
729 			(id - datafab_usb_ids) + datafab_unusual_dev_list,
730 			&datafab_host_template);
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 =		DRV_NAME,
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 	.no_dynamic_id = 1,
755 };
756 
757 module_usb_stor_driver(datafab_driver, datafab_host_template, DRV_NAME);
758