xref: /openbmc/linux/drivers/usb/storage/usb.c (revision a9fb6d05d59c9e118ad8c355adfdf88c970c61bc)
1 /* Driver for USB Mass Storage compliant devices
2  *
3  * Current development and maintenance by:
4  *   (c) 1999-2003 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
5  *
6  * Developed with the assistance of:
7  *   (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
8  *   (c) 2003-2009 Alan Stern (stern@rowland.harvard.edu)
9  *
10  * Initial work by:
11  *   (c) 1999 Michael Gee (michael@linuxspecific.com)
12  *
13  * usb_device_id support by Adam J. Richter (adam@yggdrasil.com):
14  *   (c) 2000 Yggdrasil Computing, Inc.
15  *
16  * This driver is based on the 'USB Mass Storage Class' document. This
17  * describes in detail the protocol used to communicate with such
18  * devices.  Clearly, the designers had SCSI and ATAPI commands in
19  * mind when they created this document.  The commands are all very
20  * similar to commands in the SCSI-II and ATAPI specifications.
21  *
22  * It is important to note that in a number of cases this class
23  * exhibits class-specific exemptions from the USB specification.
24  * Notably the usage of NAK, STALL and ACK differs from the norm, in
25  * that they are used to communicate wait, failed and OK on commands.
26  *
27  * Also, for certain devices, the interrupt endpoint is used to convey
28  * status of a command.
29  *
30  * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
31  * information about this driver.
32  *
33  * This program is free software; you can redistribute it and/or modify it
34  * under the terms of the GNU General Public License as published by the
35  * Free Software Foundation; either version 2, or (at your option) any
36  * later version.
37  *
38  * This program is distributed in the hope that it will be useful, but
39  * WITHOUT ANY WARRANTY; without even the implied warranty of
40  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
41  * General Public License for more details.
42  *
43  * You should have received a copy of the GNU General Public License along
44  * with this program; if not, write to the Free Software Foundation, Inc.,
45  * 675 Mass Ave, Cambridge, MA 02139, USA.
46  */
47 
48 #include <linux/sched.h>
49 #include <linux/errno.h>
50 #include <linux/freezer.h>
51 #include <linux/module.h>
52 #include <linux/init.h>
53 #include <linux/slab.h>
54 #include <linux/kthread.h>
55 #include <linux/mutex.h>
56 #include <linux/utsname.h>
57 
58 #include <scsi/scsi.h>
59 #include <scsi/scsi_cmnd.h>
60 #include <scsi/scsi_device.h>
61 
62 #include "usb.h"
63 #include "scsiglue.h"
64 #include "transport.h"
65 #include "protocol.h"
66 #include "debug.h"
67 #include "initializers.h"
68 
69 #ifdef CONFIG_USB_STORAGE_ONETOUCH
70 #include "onetouch.h"
71 #endif
72 #ifdef CONFIG_USB_STORAGE_ALAUDA
73 #include "alauda.h"
74 #endif
75 #ifdef CONFIG_USB_STORAGE_KARMA
76 #include "karma.h"
77 #endif
78 #include "sierra_ms.h"
79 #include "option_ms.h"
80 
81 /* Some informational data */
82 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
83 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
84 MODULE_LICENSE("GPL");
85 
86 static unsigned int delay_use = 5;
87 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
88 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
89 
90 static char quirks[128];
91 module_param_string(quirks, quirks, sizeof(quirks), S_IRUGO | S_IWUSR);
92 MODULE_PARM_DESC(quirks, "supplemental list of device IDs and their quirks");
93 
94 
95 /*
96  * The entries in this table correspond, line for line,
97  * with the entries in usb_storage_usb_ids[], defined in usual-tables.c.
98  */
99 
100 /* The vendor name should be kept at eight characters or less, and
101  * the product name should be kept at 16 characters or less. If a device
102  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
103  * normally generated by a device thorugh the INQUIRY response will be
104  * taken from this list, and this is the reason for the above size
105  * restriction. However, if the flag is not present, then you
106  * are free to use as many characters as you like.
107  */
108 
109 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
110 		    vendor_name, product_name, use_protocol, use_transport, \
111 		    init_function, Flags) \
112 { \
113 	.vendorName = vendor_name,	\
114 	.productName = product_name,	\
115 	.useProtocol = use_protocol,	\
116 	.useTransport = use_transport,	\
117 	.initFunction = init_function,	\
118 }
119 
120 #define COMPLIANT_DEV	UNUSUAL_DEV
121 
122 #define USUAL_DEV(use_protocol, use_transport, use_type) \
123 { \
124 	.useProtocol = use_protocol,	\
125 	.useTransport = use_transport,	\
126 }
127 
128 static struct us_unusual_dev us_unusual_dev_list[] = {
129 #	include "unusual_devs.h"
130 	{ }		/* Terminating entry */
131 };
132 
133 #undef UNUSUAL_DEV
134 #undef COMPLIANT_DEV
135 #undef USUAL_DEV
136 
137 
138 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
139 
140 int usb_stor_suspend(struct usb_interface *iface, pm_message_t message)
141 {
142 	struct us_data *us = usb_get_intfdata(iface);
143 
144 	/* Wait until no command is running */
145 	mutex_lock(&us->dev_mutex);
146 
147 	US_DEBUGP("%s\n", __func__);
148 	if (us->suspend_resume_hook)
149 		(us->suspend_resume_hook)(us, US_SUSPEND);
150 
151 	/* When runtime PM is working, we'll set a flag to indicate
152 	 * whether we should autoresume when a SCSI request arrives. */
153 
154 	mutex_unlock(&us->dev_mutex);
155 	return 0;
156 }
157 EXPORT_SYMBOL_GPL(usb_stor_suspend);
158 
159 int usb_stor_resume(struct usb_interface *iface)
160 {
161 	struct us_data *us = usb_get_intfdata(iface);
162 
163 	mutex_lock(&us->dev_mutex);
164 
165 	US_DEBUGP("%s\n", __func__);
166 	if (us->suspend_resume_hook)
167 		(us->suspend_resume_hook)(us, US_RESUME);
168 
169 	mutex_unlock(&us->dev_mutex);
170 	return 0;
171 }
172 EXPORT_SYMBOL_GPL(usb_stor_resume);
173 
174 int usb_stor_reset_resume(struct usb_interface *iface)
175 {
176 	struct us_data *us = usb_get_intfdata(iface);
177 
178 	US_DEBUGP("%s\n", __func__);
179 
180 	/* Report the reset to the SCSI core */
181 	usb_stor_report_bus_reset(us);
182 
183 	/* FIXME: Notify the subdrivers that they need to reinitialize
184 	 * the device */
185 	return 0;
186 }
187 EXPORT_SYMBOL_GPL(usb_stor_reset_resume);
188 
189 #endif /* CONFIG_PM */
190 
191 /*
192  * The next two routines get called just before and just after
193  * a USB port reset, whether from this driver or a different one.
194  */
195 
196 int usb_stor_pre_reset(struct usb_interface *iface)
197 {
198 	struct us_data *us = usb_get_intfdata(iface);
199 
200 	US_DEBUGP("%s\n", __func__);
201 
202 	/* Make sure no command runs during the reset */
203 	mutex_lock(&us->dev_mutex);
204 	return 0;
205 }
206 EXPORT_SYMBOL_GPL(usb_stor_pre_reset);
207 
208 int usb_stor_post_reset(struct usb_interface *iface)
209 {
210 	struct us_data *us = usb_get_intfdata(iface);
211 
212 	US_DEBUGP("%s\n", __func__);
213 
214 	/* Report the reset to the SCSI core */
215 	usb_stor_report_bus_reset(us);
216 
217 	/* FIXME: Notify the subdrivers that they need to reinitialize
218 	 * the device */
219 
220 	mutex_unlock(&us->dev_mutex);
221 	return 0;
222 }
223 EXPORT_SYMBOL_GPL(usb_stor_post_reset);
224 
225 /*
226  * fill_inquiry_response takes an unsigned char array (which must
227  * be at least 36 characters) and populates the vendor name,
228  * product name, and revision fields. Then the array is copied
229  * into the SCSI command's response buffer (oddly enough
230  * called request_buffer). data_len contains the length of the
231  * data array, which again must be at least 36.
232  */
233 
234 void fill_inquiry_response(struct us_data *us, unsigned char *data,
235 		unsigned int data_len)
236 {
237 	if (data_len<36) // You lose.
238 		return;
239 
240 	if(data[0]&0x20) { /* USB device currently not connected. Return
241 			      peripheral qualifier 001b ("...however, the
242 			      physical device is not currently connected
243 			      to this logical unit") and leave vendor and
244 			      product identification empty. ("If the target
245 			      does store some of the INQUIRY data on the
246 			      device, it may return zeros or ASCII spaces
247 			      (20h) in those fields until the data is
248 			      available from the device."). */
249 		memset(data+8,0,28);
250 	} else {
251 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
252 		memcpy(data+8, us->unusual_dev->vendorName,
253 			strlen(us->unusual_dev->vendorName) > 8 ? 8 :
254 			strlen(us->unusual_dev->vendorName));
255 		memcpy(data+16, us->unusual_dev->productName,
256 			strlen(us->unusual_dev->productName) > 16 ? 16 :
257 			strlen(us->unusual_dev->productName));
258 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
259 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
260 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
261 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
262 	}
263 
264 	usb_stor_set_xfer_buf(data, data_len, us->srb);
265 }
266 EXPORT_SYMBOL_GPL(fill_inquiry_response);
267 
268 static int usb_stor_control_thread(void * __us)
269 {
270 	struct us_data *us = (struct us_data *)__us;
271 	struct Scsi_Host *host = us_to_host(us);
272 
273 	for(;;) {
274 		US_DEBUGP("*** thread sleeping.\n");
275 		if (wait_for_completion_interruptible(&us->cmnd_ready))
276 			break;
277 
278 		US_DEBUGP("*** thread awakened.\n");
279 
280 		/* lock the device pointers */
281 		mutex_lock(&(us->dev_mutex));
282 
283 		/* lock access to the state */
284 		scsi_lock(host);
285 
286 		/* When we are called with no command pending, we're done */
287 		if (us->srb == NULL) {
288 			scsi_unlock(host);
289 			mutex_unlock(&us->dev_mutex);
290 			US_DEBUGP("-- exiting\n");
291 			break;
292 		}
293 
294 		/* has the command timed out *already* ? */
295 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
296 			us->srb->result = DID_ABORT << 16;
297 			goto SkipForAbort;
298 		}
299 
300 		scsi_unlock(host);
301 
302 		/* reject the command if the direction indicator
303 		 * is UNKNOWN
304 		 */
305 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
306 			US_DEBUGP("UNKNOWN data direction\n");
307 			us->srb->result = DID_ERROR << 16;
308 		}
309 
310 		/* reject if target != 0 or if LUN is higher than
311 		 * the maximum known LUN
312 		 */
313 		else if (us->srb->device->id &&
314 				!(us->fflags & US_FL_SCM_MULT_TARG)) {
315 			US_DEBUGP("Bad target number (%d:%d)\n",
316 				  us->srb->device->id, us->srb->device->lun);
317 			us->srb->result = DID_BAD_TARGET << 16;
318 		}
319 
320 		else if (us->srb->device->lun > us->max_lun) {
321 			US_DEBUGP("Bad LUN (%d:%d)\n",
322 				  us->srb->device->id, us->srb->device->lun);
323 			us->srb->result = DID_BAD_TARGET << 16;
324 		}
325 
326 		/* Handle those devices which need us to fake
327 		 * their inquiry data */
328 		else if ((us->srb->cmnd[0] == INQUIRY) &&
329 			    (us->fflags & US_FL_FIX_INQUIRY)) {
330 			unsigned char data_ptr[36] = {
331 			    0x00, 0x80, 0x02, 0x02,
332 			    0x1F, 0x00, 0x00, 0x00};
333 
334 			US_DEBUGP("Faking INQUIRY command\n");
335 			fill_inquiry_response(us, data_ptr, 36);
336 			us->srb->result = SAM_STAT_GOOD;
337 		}
338 
339 		/* we've got a command, let's do it! */
340 		else {
341 			US_DEBUG(usb_stor_show_command(us->srb));
342 			us->proto_handler(us->srb, us);
343 		}
344 
345 		/* lock access to the state */
346 		scsi_lock(host);
347 
348 		/* indicate that the command is done */
349 		if (us->srb->result != DID_ABORT << 16) {
350 			US_DEBUGP("scsi cmd done, result=0x%x\n",
351 				   us->srb->result);
352 			us->srb->scsi_done(us->srb);
353 		} else {
354 SkipForAbort:
355 			US_DEBUGP("scsi command aborted\n");
356 		}
357 
358 		/* If an abort request was received we need to signal that
359 		 * the abort has finished.  The proper test for this is
360 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
361 		 * the timeout might have occurred after the command had
362 		 * already completed with a different result code. */
363 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
364 			complete(&(us->notify));
365 
366 			/* Allow USB transfers to resume */
367 			clear_bit(US_FLIDX_ABORTING, &us->dflags);
368 			clear_bit(US_FLIDX_TIMED_OUT, &us->dflags);
369 		}
370 
371 		/* finished working on this command */
372 		us->srb = NULL;
373 		scsi_unlock(host);
374 
375 		/* unlock the device pointers */
376 		mutex_unlock(&us->dev_mutex);
377 	} /* for (;;) */
378 
379 	/* Wait until we are told to stop */
380 	for (;;) {
381 		set_current_state(TASK_INTERRUPTIBLE);
382 		if (kthread_should_stop())
383 			break;
384 		schedule();
385 	}
386 	__set_current_state(TASK_RUNNING);
387 	return 0;
388 }
389 
390 /***********************************************************************
391  * Device probing and disconnecting
392  ***********************************************************************/
393 
394 /* Associate our private data with the USB device */
395 static int associate_dev(struct us_data *us, struct usb_interface *intf)
396 {
397 	US_DEBUGP("-- %s\n", __func__);
398 
399 	/* Fill in the device-related fields */
400 	us->pusb_dev = interface_to_usbdev(intf);
401 	us->pusb_intf = intf;
402 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
403 	US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
404 			le16_to_cpu(us->pusb_dev->descriptor.idVendor),
405 			le16_to_cpu(us->pusb_dev->descriptor.idProduct),
406 			le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
407 	US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
408 			intf->cur_altsetting->desc.bInterfaceSubClass,
409 			intf->cur_altsetting->desc.bInterfaceProtocol);
410 
411 	/* Store our private data in the interface */
412 	usb_set_intfdata(intf, us);
413 
414 	/* Allocate the device-related DMA-mapped buffers */
415 	us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
416 			GFP_KERNEL, &us->cr_dma);
417 	if (!us->cr) {
418 		US_DEBUGP("usb_ctrlrequest allocation failed\n");
419 		return -ENOMEM;
420 	}
421 
422 	us->iobuf = usb_buffer_alloc(us->pusb_dev, US_IOBUF_SIZE,
423 			GFP_KERNEL, &us->iobuf_dma);
424 	if (!us->iobuf) {
425 		US_DEBUGP("I/O buffer allocation failed\n");
426 		return -ENOMEM;
427 	}
428 	return 0;
429 }
430 
431 /* Works only for digits and letters, but small and fast */
432 #define TOLOWER(x) ((x) | 0x20)
433 
434 /* Adjust device flags based on the "quirks=" module parameter */
435 static void adjust_quirks(struct us_data *us)
436 {
437 	char *p;
438 	u16 vid = le16_to_cpu(us->pusb_dev->descriptor.idVendor);
439 	u16 pid = le16_to_cpu(us->pusb_dev->descriptor.idProduct);
440 	unsigned f = 0;
441 	unsigned int mask = (US_FL_SANE_SENSE | US_FL_FIX_CAPACITY |
442 			US_FL_CAPACITY_HEURISTICS | US_FL_IGNORE_DEVICE |
443 			US_FL_NOT_LOCKABLE | US_FL_MAX_SECTORS_64 |
444 			US_FL_CAPACITY_OK | US_FL_IGNORE_RESIDUE |
445 			US_FL_SINGLE_LUN | US_FL_NO_WP_DETECT);
446 
447 	p = quirks;
448 	while (*p) {
449 		/* Each entry consists of VID:PID:flags */
450 		if (vid == simple_strtoul(p, &p, 16) &&
451 				*p == ':' &&
452 				pid == simple_strtoul(p+1, &p, 16) &&
453 				*p == ':')
454 			break;
455 
456 		/* Move forward to the next entry */
457 		while (*p) {
458 			if (*p++ == ',')
459 				break;
460 		}
461 	}
462 	if (!*p)	/* No match */
463 		return;
464 
465 	/* Collect the flags */
466 	while (*++p && *p != ',') {
467 		switch (TOLOWER(*p)) {
468 		case 'a':
469 			f |= US_FL_SANE_SENSE;
470 			break;
471 		case 'c':
472 			f |= US_FL_FIX_CAPACITY;
473 			break;
474 		case 'h':
475 			f |= US_FL_CAPACITY_HEURISTICS;
476 			break;
477 		case 'i':
478 			f |= US_FL_IGNORE_DEVICE;
479 			break;
480 		case 'l':
481 			f |= US_FL_NOT_LOCKABLE;
482 			break;
483 		case 'm':
484 			f |= US_FL_MAX_SECTORS_64;
485 			break;
486 		case 'o':
487 			f |= US_FL_CAPACITY_OK;
488 			break;
489 		case 'r':
490 			f |= US_FL_IGNORE_RESIDUE;
491 			break;
492 		case 's':
493 			f |= US_FL_SINGLE_LUN;
494 			break;
495 		case 'w':
496 			f |= US_FL_NO_WP_DETECT;
497 			break;
498 		/* Ignore unrecognized flag characters */
499 		}
500 	}
501 	us->fflags = (us->fflags & ~mask) | f;
502 	dev_info(&us->pusb_intf->dev, "Quirks match for "
503 			"vid %04x pid %04x: %x\n",
504 			vid, pid, f);
505 }
506 
507 /* Get the unusual_devs entries and the string descriptors */
508 static int get_device_info(struct us_data *us, const struct usb_device_id *id,
509 		struct us_unusual_dev *unusual_dev)
510 {
511 	struct usb_device *dev = us->pusb_dev;
512 	struct usb_interface_descriptor *idesc =
513 		&us->pusb_intf->cur_altsetting->desc;
514 
515 	/* Store the entries */
516 	us->unusual_dev = unusual_dev;
517 	us->subclass = (unusual_dev->useProtocol == US_SC_DEVICE) ?
518 			idesc->bInterfaceSubClass :
519 			unusual_dev->useProtocol;
520 	us->protocol = (unusual_dev->useTransport == US_PR_DEVICE) ?
521 			idesc->bInterfaceProtocol :
522 			unusual_dev->useTransport;
523 	us->fflags = USB_US_ORIG_FLAGS(id->driver_info);
524 	adjust_quirks(us);
525 
526 	if (us->fflags & US_FL_IGNORE_DEVICE) {
527 		printk(KERN_INFO USB_STORAGE "device ignored\n");
528 		return -ENODEV;
529 	}
530 
531 	/*
532 	 * This flag is only needed when we're in high-speed, so let's
533 	 * disable it if we're in full-speed
534 	 */
535 	if (dev->speed != USB_SPEED_HIGH)
536 		us->fflags &= ~US_FL_GO_SLOW;
537 
538 	/* Log a message if a non-generic unusual_dev entry contains an
539 	 * unnecessary subclass or protocol override.  This may stimulate
540 	 * reports from users that will help us remove unneeded entries
541 	 * from the unusual_devs.h table.
542 	 */
543 	if (id->idVendor || id->idProduct) {
544 		static const char *msgs[3] = {
545 			"an unneeded SubClass entry",
546 			"an unneeded Protocol entry",
547 			"unneeded SubClass and Protocol entries"};
548 		struct usb_device_descriptor *ddesc = &dev->descriptor;
549 		int msg = -1;
550 
551 		if (unusual_dev->useProtocol != US_SC_DEVICE &&
552 			us->subclass == idesc->bInterfaceSubClass)
553 			msg += 1;
554 		if (unusual_dev->useTransport != US_PR_DEVICE &&
555 			us->protocol == idesc->bInterfaceProtocol)
556 			msg += 2;
557 		if (msg >= 0 && !(us->fflags & US_FL_NEED_OVERRIDE))
558 			printk(KERN_NOTICE USB_STORAGE "This device "
559 				"(%04x,%04x,%04x S %02x P %02x)"
560 				" has %s in unusual_devs.h (kernel"
561 				" %s)\n"
562 				"   Please send a copy of this message to "
563 				"<linux-usb@vger.kernel.org> and "
564 				"<usb-storage@lists.one-eyed-alien.net>\n",
565 				le16_to_cpu(ddesc->idVendor),
566 				le16_to_cpu(ddesc->idProduct),
567 				le16_to_cpu(ddesc->bcdDevice),
568 				idesc->bInterfaceSubClass,
569 				idesc->bInterfaceProtocol,
570 				msgs[msg],
571 				utsname()->release);
572 	}
573 
574 	return 0;
575 }
576 
577 /* Get the transport settings */
578 static void get_transport(struct us_data *us)
579 {
580 	switch (us->protocol) {
581 	case US_PR_CB:
582 		us->transport_name = "Control/Bulk";
583 		us->transport = usb_stor_CB_transport;
584 		us->transport_reset = usb_stor_CB_reset;
585 		us->max_lun = 7;
586 		break;
587 
588 	case US_PR_CBI:
589 		us->transport_name = "Control/Bulk/Interrupt";
590 		us->transport = usb_stor_CB_transport;
591 		us->transport_reset = usb_stor_CB_reset;
592 		us->max_lun = 7;
593 		break;
594 
595 	case US_PR_BULK:
596 		us->transport_name = "Bulk";
597 		us->transport = usb_stor_Bulk_transport;
598 		us->transport_reset = usb_stor_Bulk_reset;
599 		break;
600 
601 #ifdef CONFIG_USB_STORAGE_ALAUDA
602 	case US_PR_ALAUDA:
603 		us->transport_name  = "Alauda Control/Bulk";
604 		us->transport = alauda_transport;
605 		us->transport_reset = usb_stor_Bulk_reset;
606 		us->max_lun = 1;
607 		break;
608 #endif
609 
610 #ifdef CONFIG_USB_STORAGE_KARMA
611 	case US_PR_KARMA:
612 		us->transport_name = "Rio Karma/Bulk";
613 		us->transport = rio_karma_transport;
614 		us->transport_reset = usb_stor_Bulk_reset;
615 		break;
616 #endif
617 
618 	}
619 }
620 
621 /* Get the protocol settings */
622 static void get_protocol(struct us_data *us)
623 {
624 	switch (us->subclass) {
625 	case US_SC_RBC:
626 		us->protocol_name = "Reduced Block Commands (RBC)";
627 		us->proto_handler = usb_stor_transparent_scsi_command;
628 		break;
629 
630 	case US_SC_8020:
631 		us->protocol_name = "8020i";
632 		us->proto_handler = usb_stor_pad12_command;
633 		us->max_lun = 0;
634 		break;
635 
636 	case US_SC_QIC:
637 		us->protocol_name = "QIC-157";
638 		us->proto_handler = usb_stor_pad12_command;
639 		us->max_lun = 0;
640 		break;
641 
642 	case US_SC_8070:
643 		us->protocol_name = "8070i";
644 		us->proto_handler = usb_stor_pad12_command;
645 		us->max_lun = 0;
646 		break;
647 
648 	case US_SC_SCSI:
649 		us->protocol_name = "Transparent SCSI";
650 		us->proto_handler = usb_stor_transparent_scsi_command;
651 		break;
652 
653 	case US_SC_UFI:
654 		us->protocol_name = "Uniform Floppy Interface (UFI)";
655 		us->proto_handler = usb_stor_ufi_command;
656 		break;
657 	}
658 }
659 
660 /* Get the pipe settings */
661 static int get_pipes(struct us_data *us)
662 {
663 	struct usb_host_interface *altsetting =
664 		us->pusb_intf->cur_altsetting;
665 	int i;
666 	struct usb_endpoint_descriptor *ep;
667 	struct usb_endpoint_descriptor *ep_in = NULL;
668 	struct usb_endpoint_descriptor *ep_out = NULL;
669 	struct usb_endpoint_descriptor *ep_int = NULL;
670 
671 	/*
672 	 * Find the first endpoint of each type we need.
673 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
674 	 * An optional interrupt-in is OK (necessary for CBI protocol).
675 	 * We will ignore any others.
676 	 */
677 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
678 		ep = &altsetting->endpoint[i].desc;
679 
680 		if (usb_endpoint_xfer_bulk(ep)) {
681 			if (usb_endpoint_dir_in(ep)) {
682 				if (!ep_in)
683 					ep_in = ep;
684 			} else {
685 				if (!ep_out)
686 					ep_out = ep;
687 			}
688 		}
689 
690 		else if (usb_endpoint_is_int_in(ep)) {
691 			if (!ep_int)
692 				ep_int = ep;
693 		}
694 	}
695 
696 	if (!ep_in || !ep_out || (us->protocol == US_PR_CBI && !ep_int)) {
697 		US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
698 		return -EIO;
699 	}
700 
701 	/* Calculate and store the pipe values */
702 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
703 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
704 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
705 		usb_endpoint_num(ep_out));
706 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
707 		usb_endpoint_num(ep_in));
708 	if (ep_int) {
709 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
710 			usb_endpoint_num(ep_int));
711 		us->ep_bInterval = ep_int->bInterval;
712 	}
713 	return 0;
714 }
715 
716 /* Initialize all the dynamic resources we need */
717 static int usb_stor_acquire_resources(struct us_data *us)
718 {
719 	int p;
720 	struct task_struct *th;
721 
722 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
723 	if (!us->current_urb) {
724 		US_DEBUGP("URB allocation failed\n");
725 		return -ENOMEM;
726 	}
727 
728 	/* Just before we start our control thread, initialize
729 	 * the device if it needs initialization */
730 	if (us->unusual_dev->initFunction) {
731 		p = us->unusual_dev->initFunction(us);
732 		if (p)
733 			return p;
734 	}
735 
736 	/* Start up our control thread */
737 	th = kthread_run(usb_stor_control_thread, us, "usb-storage");
738 	if (IS_ERR(th)) {
739 		printk(KERN_WARNING USB_STORAGE
740 		       "Unable to start control thread\n");
741 		return PTR_ERR(th);
742 	}
743 	us->ctl_thread = th;
744 
745 	return 0;
746 }
747 
748 /* Release all our dynamic resources */
749 static void usb_stor_release_resources(struct us_data *us)
750 {
751 	US_DEBUGP("-- %s\n", __func__);
752 
753 	/* Tell the control thread to exit.  The SCSI host must
754 	 * already have been removed and the DISCONNECTING flag set
755 	 * so that we won't accept any more commands.
756 	 */
757 	US_DEBUGP("-- sending exit command to thread\n");
758 	complete(&us->cmnd_ready);
759 	if (us->ctl_thread)
760 		kthread_stop(us->ctl_thread);
761 
762 	/* Call the destructor routine, if it exists */
763 	if (us->extra_destructor) {
764 		US_DEBUGP("-- calling extra_destructor()\n");
765 		us->extra_destructor(us->extra);
766 	}
767 
768 	/* Free the extra data and the URB */
769 	kfree(us->extra);
770 	usb_free_urb(us->current_urb);
771 }
772 
773 /* Dissociate from the USB device */
774 static void dissociate_dev(struct us_data *us)
775 {
776 	US_DEBUGP("-- %s\n", __func__);
777 
778 	/* Free the device-related DMA-mapped buffers */
779 	if (us->cr)
780 		usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
781 				us->cr_dma);
782 	if (us->iobuf)
783 		usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
784 				us->iobuf_dma);
785 
786 	/* Remove our private data from the interface */
787 	usb_set_intfdata(us->pusb_intf, NULL);
788 }
789 
790 /* First stage of disconnect processing: stop SCSI scanning,
791  * remove the host, and stop accepting new commands
792  */
793 static void quiesce_and_remove_host(struct us_data *us)
794 {
795 	struct Scsi_Host *host = us_to_host(us);
796 
797 	/* If the device is really gone, cut short reset delays */
798 	if (us->pusb_dev->state == USB_STATE_NOTATTACHED)
799 		set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
800 
801 	/* Prevent SCSI-scanning (if it hasn't started yet)
802 	 * and wait for the SCSI-scanning thread to stop.
803 	 */
804 	set_bit(US_FLIDX_DONT_SCAN, &us->dflags);
805 	wake_up(&us->delay_wait);
806 	wait_for_completion(&us->scanning_done);
807 
808 	/* Removing the host will perform an orderly shutdown: caches
809 	 * synchronized, disks spun down, etc.
810 	 */
811 	scsi_remove_host(host);
812 
813 	/* Prevent any new commands from being accepted and cut short
814 	 * reset delays.
815 	 */
816 	scsi_lock(host);
817 	set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
818 	scsi_unlock(host);
819 	wake_up(&us->delay_wait);
820 }
821 
822 /* Second stage of disconnect processing: deallocate all resources */
823 static void release_everything(struct us_data *us)
824 {
825 	usb_stor_release_resources(us);
826 	dissociate_dev(us);
827 
828 	/* Drop our reference to the host; the SCSI core will free it
829 	 * (and "us" along with it) when the refcount becomes 0. */
830 	scsi_host_put(us_to_host(us));
831 }
832 
833 /* Thread to carry out delayed SCSI-device scanning */
834 static int usb_stor_scan_thread(void * __us)
835 {
836 	struct us_data *us = (struct us_data *)__us;
837 
838 	printk(KERN_DEBUG
839 		"usb-storage: device found at %d\n", us->pusb_dev->devnum);
840 
841 	set_freezable();
842 	/* Wait for the timeout to expire or for a disconnect */
843 	if (delay_use > 0) {
844 		printk(KERN_DEBUG "usb-storage: waiting for device "
845 				"to settle before scanning\n");
846 		wait_event_freezable_timeout(us->delay_wait,
847 				test_bit(US_FLIDX_DONT_SCAN, &us->dflags),
848 				delay_use * HZ);
849 	}
850 
851 	/* If the device is still connected, perform the scanning */
852 	if (!test_bit(US_FLIDX_DONT_SCAN, &us->dflags)) {
853 
854 		/* For bulk-only devices, determine the max LUN value */
855 		if (us->protocol == US_PR_BULK &&
856 				!(us->fflags & US_FL_SINGLE_LUN)) {
857 			mutex_lock(&us->dev_mutex);
858 			us->max_lun = usb_stor_Bulk_max_lun(us);
859 			mutex_unlock(&us->dev_mutex);
860 		}
861 		scsi_scan_host(us_to_host(us));
862 		printk(KERN_DEBUG "usb-storage: device scan complete\n");
863 
864 		/* Should we unbind if no devices were detected? */
865 	}
866 
867 	complete_and_exit(&us->scanning_done, 0);
868 }
869 
870 
871 /* First part of general USB mass-storage probing */
872 int usb_stor_probe1(struct us_data **pus,
873 		struct usb_interface *intf,
874 		const struct usb_device_id *id,
875 		struct us_unusual_dev *unusual_dev)
876 {
877 	struct Scsi_Host *host;
878 	struct us_data *us;
879 	int result;
880 
881 	US_DEBUGP("USB Mass Storage device detected\n");
882 
883 	/*
884 	 * Ask the SCSI layer to allocate a host structure, with extra
885 	 * space at the end for our private us_data structure.
886 	 */
887 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
888 	if (!host) {
889 		printk(KERN_WARNING USB_STORAGE
890 			"Unable to allocate the scsi host\n");
891 		return -ENOMEM;
892 	}
893 
894 	/*
895 	 * Allow 16-byte CDBs and thus > 2TB
896 	 */
897 	host->max_cmd_len = 16;
898 	*pus = us = host_to_us(host);
899 	memset(us, 0, sizeof(struct us_data));
900 	mutex_init(&(us->dev_mutex));
901 	init_completion(&us->cmnd_ready);
902 	init_completion(&(us->notify));
903 	init_waitqueue_head(&us->delay_wait);
904 	init_completion(&us->scanning_done);
905 
906 	/* Associate the us_data structure with the USB device */
907 	result = associate_dev(us, intf);
908 	if (result)
909 		goto BadDevice;
910 
911 	/* Get the unusual_devs entries and the descriptors */
912 	result = get_device_info(us, id, unusual_dev);
913 	if (result)
914 		goto BadDevice;
915 
916 	/* Get standard transport and protocol settings */
917 	get_transport(us);
918 	get_protocol(us);
919 
920 	/* Give the caller a chance to fill in specialized transport
921 	 * or protocol settings.
922 	 */
923 	return 0;
924 
925 BadDevice:
926 	US_DEBUGP("storage_probe() failed\n");
927 	release_everything(us);
928 	return result;
929 }
930 EXPORT_SYMBOL_GPL(usb_stor_probe1);
931 
932 /* Second part of general USB mass-storage probing */
933 int usb_stor_probe2(struct us_data *us)
934 {
935 	struct task_struct *th;
936 	int result;
937 
938 	/* Make sure the transport and protocol have both been set */
939 	if (!us->transport || !us->proto_handler) {
940 		result = -ENXIO;
941 		goto BadDevice;
942 	}
943 	US_DEBUGP("Transport: %s\n", us->transport_name);
944 	US_DEBUGP("Protocol: %s\n", us->protocol_name);
945 
946 	/* fix for single-lun devices */
947 	if (us->fflags & US_FL_SINGLE_LUN)
948 		us->max_lun = 0;
949 
950 	/* Find the endpoints and calculate pipe values */
951 	result = get_pipes(us);
952 	if (result)
953 		goto BadDevice;
954 
955 	/* Acquire all the other resources and add the host */
956 	result = usb_stor_acquire_resources(us);
957 	if (result)
958 		goto BadDevice;
959 	result = scsi_add_host(us_to_host(us), &us->pusb_intf->dev);
960 	if (result) {
961 		printk(KERN_WARNING USB_STORAGE
962 			"Unable to add the scsi host\n");
963 		goto BadDevice;
964 	}
965 
966 	/* Start up the thread for delayed SCSI-device scanning */
967 	th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
968 	if (IS_ERR(th)) {
969 		printk(KERN_WARNING USB_STORAGE
970 		       "Unable to start the device-scanning thread\n");
971 		complete(&us->scanning_done);
972 		quiesce_and_remove_host(us);
973 		result = PTR_ERR(th);
974 		goto BadDevice;
975 	}
976 
977 	wake_up_process(th);
978 
979 	return 0;
980 
981 	/* We come here if there are any problems */
982 BadDevice:
983 	US_DEBUGP("storage_probe() failed\n");
984 	release_everything(us);
985 	return result;
986 }
987 EXPORT_SYMBOL_GPL(usb_stor_probe2);
988 
989 /* Handle a USB mass-storage disconnect */
990 void usb_stor_disconnect(struct usb_interface *intf)
991 {
992 	struct us_data *us = usb_get_intfdata(intf);
993 
994 	US_DEBUGP("storage_disconnect() called\n");
995 	quiesce_and_remove_host(us);
996 	release_everything(us);
997 }
998 EXPORT_SYMBOL_GPL(usb_stor_disconnect);
999 
1000 /* The main probe routine for standard devices */
1001 static int storage_probe(struct usb_interface *intf,
1002 			 const struct usb_device_id *id)
1003 {
1004 	struct us_data *us;
1005 	int result;
1006 
1007 	/*
1008 	 * If libusual is configured, let it decide whether a standard
1009 	 * device should be handled by usb-storage or by ub.
1010 	 * If the device isn't standard (is handled by a subdriver
1011 	 * module) then don't accept it.
1012 	 */
1013 	if (usb_usual_check_type(id, USB_US_TYPE_STOR) ||
1014 			usb_usual_ignore_device(intf))
1015 		return -ENXIO;
1016 
1017 	/*
1018 	 * Call the general probe procedures.
1019 	 *
1020 	 * The unusual_dev_list array is parallel to the usb_storage_usb_ids
1021 	 * table, so we use the index of the id entry to find the
1022 	 * corresponding unusual_devs entry.
1023 	 */
1024 	result = usb_stor_probe1(&us, intf, id,
1025 			(id - usb_storage_usb_ids) + us_unusual_dev_list);
1026 	if (result)
1027 		return result;
1028 
1029 	/* No special transport or protocol settings in the main module */
1030 
1031 	result = usb_stor_probe2(us);
1032 	return result;
1033 }
1034 
1035 /***********************************************************************
1036  * Initialization and registration
1037  ***********************************************************************/
1038 
1039 static struct usb_driver usb_storage_driver = {
1040 	.name =		"usb-storage",
1041 	.probe =	storage_probe,
1042 	.disconnect =	usb_stor_disconnect,
1043 	.suspend =	usb_stor_suspend,
1044 	.resume =	usb_stor_resume,
1045 	.reset_resume =	usb_stor_reset_resume,
1046 	.pre_reset =	usb_stor_pre_reset,
1047 	.post_reset =	usb_stor_post_reset,
1048 	.id_table =	usb_storage_usb_ids,
1049 	.soft_unbind =	1,
1050 };
1051 
1052 static int __init usb_stor_init(void)
1053 {
1054 	int retval;
1055 
1056 	printk(KERN_INFO "Initializing USB Mass Storage driver...\n");
1057 
1058 	/* register the driver, return usb_register return code if error */
1059 	retval = usb_register(&usb_storage_driver);
1060 	if (retval == 0) {
1061 		printk(KERN_INFO "USB Mass Storage support registered.\n");
1062 		usb_usual_set_present(USB_US_TYPE_STOR);
1063 	}
1064 	return retval;
1065 }
1066 
1067 static void __exit usb_stor_exit(void)
1068 {
1069 	US_DEBUGP("usb_stor_exit() called\n");
1070 
1071 	/* Deregister the driver
1072 	 * This will cause disconnect() to be called for each
1073 	 * attached unit
1074 	 */
1075 	US_DEBUGP("-- calling usb_deregister()\n");
1076 	usb_deregister(&usb_storage_driver) ;
1077 
1078 	usb_usual_clear_present(USB_US_TYPE_STOR);
1079 }
1080 
1081 module_init(usb_stor_init);
1082 module_exit(usb_stor_exit);
1083