xref: /openbmc/linux/drivers/usb/storage/usb.c (revision 9ffc93f2)
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 #ifdef CONFIG_USB_STORAGE_DEBUG
49 #define DEBUG
50 #endif
51 
52 #include <linux/sched.h>
53 #include <linux/errno.h>
54 #include <linux/freezer.h>
55 #include <linux/module.h>
56 #include <linux/init.h>
57 #include <linux/slab.h>
58 #include <linux/kthread.h>
59 #include <linux/mutex.h>
60 #include <linux/utsname.h>
61 
62 #include <scsi/scsi.h>
63 #include <scsi/scsi_cmnd.h>
64 #include <scsi/scsi_device.h>
65 
66 #include "usb.h"
67 #include "scsiglue.h"
68 #include "transport.h"
69 #include "protocol.h"
70 #include "debug.h"
71 #include "initializers.h"
72 
73 #include "sierra_ms.h"
74 #include "option_ms.h"
75 
76 /* Some informational data */
77 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
78 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
79 MODULE_LICENSE("GPL");
80 
81 static unsigned int delay_use = 1;
82 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
83 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
84 
85 static char quirks[128];
86 module_param_string(quirks, quirks, sizeof(quirks), S_IRUGO | S_IWUSR);
87 MODULE_PARM_DESC(quirks, "supplemental list of device IDs and their quirks");
88 
89 
90 /*
91  * The entries in this table correspond, line for line,
92  * with the entries in usb_storage_usb_ids[], defined in usual-tables.c.
93  */
94 
95 /* The vendor name should be kept at eight characters or less, and
96  * the product name should be kept at 16 characters or less. If a device
97  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
98  * normally generated by a device thorugh the INQUIRY response will be
99  * taken from this list, and this is the reason for the above size
100  * restriction. However, if the flag is not present, then you
101  * are free to use as many characters as you like.
102  */
103 
104 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
105 		    vendor_name, product_name, use_protocol, use_transport, \
106 		    init_function, Flags) \
107 { \
108 	.vendorName = vendor_name,	\
109 	.productName = product_name,	\
110 	.useProtocol = use_protocol,	\
111 	.useTransport = use_transport,	\
112 	.initFunction = init_function,	\
113 }
114 
115 #define COMPLIANT_DEV	UNUSUAL_DEV
116 
117 #define USUAL_DEV(use_protocol, use_transport, use_type) \
118 { \
119 	.useProtocol = use_protocol,	\
120 	.useTransport = use_transport,	\
121 }
122 
123 static struct us_unusual_dev us_unusual_dev_list[] = {
124 #	include "unusual_devs.h"
125 	{ }		/* Terminating entry */
126 };
127 
128 static struct us_unusual_dev for_dynamic_ids =
129 		USUAL_DEV(USB_SC_SCSI, USB_PR_BULK, 0);
130 
131 #undef UNUSUAL_DEV
132 #undef COMPLIANT_DEV
133 #undef USUAL_DEV
134 
135 
136 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
137 
138 int usb_stor_suspend(struct usb_interface *iface, pm_message_t message)
139 {
140 	struct us_data *us = usb_get_intfdata(iface);
141 
142 	/* Wait until no command is running */
143 	mutex_lock(&us->dev_mutex);
144 
145 	US_DEBUGP("%s\n", __func__);
146 	if (us->suspend_resume_hook)
147 		(us->suspend_resume_hook)(us, US_SUSPEND);
148 
149 	/* When runtime PM is working, we'll set a flag to indicate
150 	 * whether we should autoresume when a SCSI request arrives. */
151 
152 	mutex_unlock(&us->dev_mutex);
153 	return 0;
154 }
155 EXPORT_SYMBOL_GPL(usb_stor_suspend);
156 
157 int usb_stor_resume(struct usb_interface *iface)
158 {
159 	struct us_data *us = usb_get_intfdata(iface);
160 
161 	mutex_lock(&us->dev_mutex);
162 
163 	US_DEBUGP("%s\n", __func__);
164 	if (us->suspend_resume_hook)
165 		(us->suspend_resume_hook)(us, US_RESUME);
166 
167 	mutex_unlock(&us->dev_mutex);
168 	return 0;
169 }
170 EXPORT_SYMBOL_GPL(usb_stor_resume);
171 
172 int usb_stor_reset_resume(struct usb_interface *iface)
173 {
174 	struct us_data *us = usb_get_intfdata(iface);
175 
176 	US_DEBUGP("%s\n", __func__);
177 
178 	/* Report the reset to the SCSI core */
179 	usb_stor_report_bus_reset(us);
180 
181 	/* FIXME: Notify the subdrivers that they need to reinitialize
182 	 * the device */
183 	return 0;
184 }
185 EXPORT_SYMBOL_GPL(usb_stor_reset_resume);
186 
187 #endif /* CONFIG_PM */
188 
189 /*
190  * The next two routines get called just before and just after
191  * a USB port reset, whether from this driver or a different one.
192  */
193 
194 int usb_stor_pre_reset(struct usb_interface *iface)
195 {
196 	struct us_data *us = usb_get_intfdata(iface);
197 
198 	US_DEBUGP("%s\n", __func__);
199 
200 	/* Make sure no command runs during the reset */
201 	mutex_lock(&us->dev_mutex);
202 	return 0;
203 }
204 EXPORT_SYMBOL_GPL(usb_stor_pre_reset);
205 
206 int usb_stor_post_reset(struct usb_interface *iface)
207 {
208 	struct us_data *us = usb_get_intfdata(iface);
209 
210 	US_DEBUGP("%s\n", __func__);
211 
212 	/* Report the reset to the SCSI core */
213 	usb_stor_report_bus_reset(us);
214 
215 	/* FIXME: Notify the subdrivers that they need to reinitialize
216 	 * the device */
217 
218 	mutex_unlock(&us->dev_mutex);
219 	return 0;
220 }
221 EXPORT_SYMBOL_GPL(usb_stor_post_reset);
222 
223 /*
224  * fill_inquiry_response takes an unsigned char array (which must
225  * be at least 36 characters) and populates the vendor name,
226  * product name, and revision fields. Then the array is copied
227  * into the SCSI command's response buffer (oddly enough
228  * called request_buffer). data_len contains the length of the
229  * data array, which again must be at least 36.
230  */
231 
232 void fill_inquiry_response(struct us_data *us, unsigned char *data,
233 		unsigned int data_len)
234 {
235 	if (data_len<36) // You lose.
236 		return;
237 
238 	memset(data+8, ' ', 28);
239 	if(data[0]&0x20) { /* USB device currently not connected. Return
240 			      peripheral qualifier 001b ("...however, the
241 			      physical device is not currently connected
242 			      to this logical unit") and leave vendor and
243 			      product identification empty. ("If the target
244 			      does store some of the INQUIRY data on the
245 			      device, it may return zeros or ASCII spaces
246 			      (20h) in those fields until the data is
247 			      available from the device."). */
248 	} else {
249 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
250 		int n;
251 
252 		n = strlen(us->unusual_dev->vendorName);
253 		memcpy(data+8, us->unusual_dev->vendorName, min(8, n));
254 		n = strlen(us->unusual_dev->productName);
255 		memcpy(data+16, us->unusual_dev->productName, min(16, n));
256 
257 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
258 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
259 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
260 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
261 	}
262 
263 	usb_stor_set_xfer_buf(data, data_len, us->srb);
264 }
265 EXPORT_SYMBOL_GPL(fill_inquiry_response);
266 
267 static int usb_stor_control_thread(void * __us)
268 {
269 	struct us_data *us = (struct us_data *)__us;
270 	struct Scsi_Host *host = us_to_host(us);
271 
272 	for(;;) {
273 		US_DEBUGP("*** thread sleeping.\n");
274 		if (wait_for_completion_interruptible(&us->cmnd_ready))
275 			break;
276 
277 		US_DEBUGP("*** thread awakened.\n");
278 
279 		/* lock the device pointers */
280 		mutex_lock(&(us->dev_mutex));
281 
282 		/* lock access to the state */
283 		scsi_lock(host);
284 
285 		/* When we are called with no command pending, we're done */
286 		if (us->srb == NULL) {
287 			scsi_unlock(host);
288 			mutex_unlock(&us->dev_mutex);
289 			US_DEBUGP("-- exiting\n");
290 			break;
291 		}
292 
293 		/* has the command timed out *already* ? */
294 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
295 			us->srb->result = DID_ABORT << 16;
296 			goto SkipForAbort;
297 		}
298 
299 		scsi_unlock(host);
300 
301 		/* reject the command if the direction indicator
302 		 * is UNKNOWN
303 		 */
304 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
305 			US_DEBUGP("UNKNOWN data direction\n");
306 			us->srb->result = DID_ERROR << 16;
307 		}
308 
309 		/* reject if target != 0 or if LUN is higher than
310 		 * the maximum known LUN
311 		 */
312 		else if (us->srb->device->id &&
313 				!(us->fflags & US_FL_SCM_MULT_TARG)) {
314 			US_DEBUGP("Bad target number (%d:%d)\n",
315 				  us->srb->device->id, us->srb->device->lun);
316 			us->srb->result = DID_BAD_TARGET << 16;
317 		}
318 
319 		else if (us->srb->device->lun > us->max_lun) {
320 			US_DEBUGP("Bad LUN (%d:%d)\n",
321 				  us->srb->device->id, us->srb->device->lun);
322 			us->srb->result = DID_BAD_TARGET << 16;
323 		}
324 
325 		/* Handle those devices which need us to fake
326 		 * their inquiry data */
327 		else if ((us->srb->cmnd[0] == INQUIRY) &&
328 			    (us->fflags & US_FL_FIX_INQUIRY)) {
329 			unsigned char data_ptr[36] = {
330 			    0x00, 0x80, 0x02, 0x02,
331 			    0x1F, 0x00, 0x00, 0x00};
332 
333 			US_DEBUGP("Faking INQUIRY command\n");
334 			fill_inquiry_response(us, data_ptr, 36);
335 			us->srb->result = SAM_STAT_GOOD;
336 		}
337 
338 		/* we've got a command, let's do it! */
339 		else {
340 			US_DEBUG(usb_stor_show_command(us->srb));
341 			us->proto_handler(us->srb, us);
342 			usb_mark_last_busy(us->pusb_dev);
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 control/setup and DMA-mapped buffers */
415 	us->cr = kmalloc(sizeof(*us->cr), GFP_KERNEL);
416 	if (!us->cr) {
417 		US_DEBUGP("usb_ctrlrequest allocation failed\n");
418 		return -ENOMEM;
419 	}
420 
421 	us->iobuf = usb_alloc_coherent(us->pusb_dev, US_IOBUF_SIZE,
422 			GFP_KERNEL, &us->iobuf_dma);
423 	if (!us->iobuf) {
424 		US_DEBUGP("I/O buffer allocation failed\n");
425 		return -ENOMEM;
426 	}
427 	return 0;
428 }
429 
430 /* Works only for digits and letters, but small and fast */
431 #define TOLOWER(x) ((x) | 0x20)
432 
433 /* Adjust device flags based on the "quirks=" module parameter */
434 static void adjust_quirks(struct us_data *us)
435 {
436 	char *p;
437 	u16 vid = le16_to_cpu(us->pusb_dev->descriptor.idVendor);
438 	u16 pid = le16_to_cpu(us->pusb_dev->descriptor.idProduct);
439 	unsigned f = 0;
440 	unsigned int mask = (US_FL_SANE_SENSE | US_FL_BAD_SENSE |
441 			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 			US_FL_NO_READ_DISC_INFO | US_FL_NO_READ_CAPACITY_16 |
447 			US_FL_INITIAL_READ10);
448 
449 	p = quirks;
450 	while (*p) {
451 		/* Each entry consists of VID:PID:flags */
452 		if (vid == simple_strtoul(p, &p, 16) &&
453 				*p == ':' &&
454 				pid == simple_strtoul(p+1, &p, 16) &&
455 				*p == ':')
456 			break;
457 
458 		/* Move forward to the next entry */
459 		while (*p) {
460 			if (*p++ == ',')
461 				break;
462 		}
463 	}
464 	if (!*p)	/* No match */
465 		return;
466 
467 	/* Collect the flags */
468 	while (*++p && *p != ',') {
469 		switch (TOLOWER(*p)) {
470 		case 'a':
471 			f |= US_FL_SANE_SENSE;
472 			break;
473 		case 'b':
474 			f |= US_FL_BAD_SENSE;
475 			break;
476 		case 'c':
477 			f |= US_FL_FIX_CAPACITY;
478 			break;
479 		case 'd':
480 			f |= US_FL_NO_READ_DISC_INFO;
481 			break;
482 		case 'e':
483 			f |= US_FL_NO_READ_CAPACITY_16;
484 			break;
485 		case 'h':
486 			f |= US_FL_CAPACITY_HEURISTICS;
487 			break;
488 		case 'i':
489 			f |= US_FL_IGNORE_DEVICE;
490 			break;
491 		case 'l':
492 			f |= US_FL_NOT_LOCKABLE;
493 			break;
494 		case 'm':
495 			f |= US_FL_MAX_SECTORS_64;
496 			break;
497 		case 'n':
498 			f |= US_FL_INITIAL_READ10;
499 			break;
500 		case 'o':
501 			f |= US_FL_CAPACITY_OK;
502 			break;
503 		case 'r':
504 			f |= US_FL_IGNORE_RESIDUE;
505 			break;
506 		case 's':
507 			f |= US_FL_SINGLE_LUN;
508 			break;
509 		case 'w':
510 			f |= US_FL_NO_WP_DETECT;
511 			break;
512 		/* Ignore unrecognized flag characters */
513 		}
514 	}
515 	us->fflags = (us->fflags & ~mask) | f;
516 }
517 
518 /* Get the unusual_devs entries and the string descriptors */
519 static int get_device_info(struct us_data *us, const struct usb_device_id *id,
520 		struct us_unusual_dev *unusual_dev)
521 {
522 	struct usb_device *dev = us->pusb_dev;
523 	struct usb_interface_descriptor *idesc =
524 		&us->pusb_intf->cur_altsetting->desc;
525 	struct device *pdev = &us->pusb_intf->dev;
526 
527 	/* Store the entries */
528 	us->unusual_dev = unusual_dev;
529 	us->subclass = (unusual_dev->useProtocol == USB_SC_DEVICE) ?
530 			idesc->bInterfaceSubClass :
531 			unusual_dev->useProtocol;
532 	us->protocol = (unusual_dev->useTransport == USB_PR_DEVICE) ?
533 			idesc->bInterfaceProtocol :
534 			unusual_dev->useTransport;
535 	us->fflags = USB_US_ORIG_FLAGS(id->driver_info);
536 	adjust_quirks(us);
537 
538 	if (us->fflags & US_FL_IGNORE_DEVICE) {
539 		dev_info(pdev, "device ignored\n");
540 		return -ENODEV;
541 	}
542 
543 	/*
544 	 * This flag is only needed when we're in high-speed, so let's
545 	 * disable it if we're in full-speed
546 	 */
547 	if (dev->speed != USB_SPEED_HIGH)
548 		us->fflags &= ~US_FL_GO_SLOW;
549 
550 	if (us->fflags)
551 		dev_info(pdev, "Quirks match for vid %04x pid %04x: %lx\n",
552 				le16_to_cpu(dev->descriptor.idVendor),
553 				le16_to_cpu(dev->descriptor.idProduct),
554 				us->fflags);
555 
556 	/* Log a message if a non-generic unusual_dev entry contains an
557 	 * unnecessary subclass or protocol override.  This may stimulate
558 	 * reports from users that will help us remove unneeded entries
559 	 * from the unusual_devs.h table.
560 	 */
561 	if (id->idVendor || id->idProduct) {
562 		static const char *msgs[3] = {
563 			"an unneeded SubClass entry",
564 			"an unneeded Protocol entry",
565 			"unneeded SubClass and Protocol entries"};
566 		struct usb_device_descriptor *ddesc = &dev->descriptor;
567 		int msg = -1;
568 
569 		if (unusual_dev->useProtocol != USB_SC_DEVICE &&
570 			us->subclass == idesc->bInterfaceSubClass)
571 			msg += 1;
572 		if (unusual_dev->useTransport != USB_PR_DEVICE &&
573 			us->protocol == idesc->bInterfaceProtocol)
574 			msg += 2;
575 		if (msg >= 0 && !(us->fflags & US_FL_NEED_OVERRIDE))
576 			dev_notice(pdev, "This device "
577 					"(%04x,%04x,%04x S %02x P %02x)"
578 					" has %s in unusual_devs.h (kernel"
579 					" %s)\n"
580 					"   Please send a copy of this message to "
581 					"<linux-usb@vger.kernel.org> and "
582 					"<usb-storage@lists.one-eyed-alien.net>\n",
583 					le16_to_cpu(ddesc->idVendor),
584 					le16_to_cpu(ddesc->idProduct),
585 					le16_to_cpu(ddesc->bcdDevice),
586 					idesc->bInterfaceSubClass,
587 					idesc->bInterfaceProtocol,
588 					msgs[msg],
589 					utsname()->release);
590 	}
591 
592 	return 0;
593 }
594 
595 /* Get the transport settings */
596 static void get_transport(struct us_data *us)
597 {
598 	switch (us->protocol) {
599 	case USB_PR_CB:
600 		us->transport_name = "Control/Bulk";
601 		us->transport = usb_stor_CB_transport;
602 		us->transport_reset = usb_stor_CB_reset;
603 		us->max_lun = 7;
604 		break;
605 
606 	case USB_PR_CBI:
607 		us->transport_name = "Control/Bulk/Interrupt";
608 		us->transport = usb_stor_CB_transport;
609 		us->transport_reset = usb_stor_CB_reset;
610 		us->max_lun = 7;
611 		break;
612 
613 	case USB_PR_BULK:
614 		us->transport_name = "Bulk";
615 		us->transport = usb_stor_Bulk_transport;
616 		us->transport_reset = usb_stor_Bulk_reset;
617 		break;
618 	}
619 }
620 
621 /* Get the protocol settings */
622 static void get_protocol(struct us_data *us)
623 {
624 	switch (us->subclass) {
625 	case USB_SC_RBC:
626 		us->protocol_name = "Reduced Block Commands (RBC)";
627 		us->proto_handler = usb_stor_transparent_scsi_command;
628 		break;
629 
630 	case USB_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 USB_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 USB_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 USB_SC_SCSI:
649 		us->protocol_name = "Transparent SCSI";
650 		us->proto_handler = usb_stor_transparent_scsi_command;
651 		break;
652 
653 	case USB_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 == USB_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 		dev_warn(&us->pusb_intf->dev,
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 buffers */
779 	kfree(us->cr);
780 	usb_free_coherent(us->pusb_dev, US_IOBUF_SIZE, us->iobuf, us->iobuf_dma);
781 
782 	/* Remove our private data from the interface */
783 	usb_set_intfdata(us->pusb_intf, NULL);
784 }
785 
786 /* First stage of disconnect processing: stop SCSI scanning,
787  * remove the host, and stop accepting new commands
788  */
789 static void quiesce_and_remove_host(struct us_data *us)
790 {
791 	struct Scsi_Host *host = us_to_host(us);
792 
793 	/* If the device is really gone, cut short reset delays */
794 	if (us->pusb_dev->state == USB_STATE_NOTATTACHED) {
795 		set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
796 		wake_up(&us->delay_wait);
797 	}
798 
799 	/* Prevent SCSI scanning (if it hasn't started yet)
800 	 * or wait for the SCSI-scanning routine to stop.
801 	 */
802 	cancel_delayed_work_sync(&us->scan_dwork);
803 
804 	/* Balance autopm calls if scanning was cancelled */
805 	if (test_bit(US_FLIDX_SCAN_PENDING, &us->dflags))
806 		usb_autopm_put_interface_no_suspend(us->pusb_intf);
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 /* Delayed-work routine to carry out SCSI-device scanning */
834 static void usb_stor_scan_dwork(struct work_struct *work)
835 {
836 	struct us_data *us = container_of(work, struct us_data,
837 			scan_dwork.work);
838 	struct device *dev = &us->pusb_intf->dev;
839 
840 	dev_dbg(dev, "starting scan\n");
841 
842 	/* For bulk-only devices, determine the max LUN value */
843 	if (us->protocol == USB_PR_BULK && !(us->fflags & US_FL_SINGLE_LUN)) {
844 		mutex_lock(&us->dev_mutex);
845 		us->max_lun = usb_stor_Bulk_max_lun(us);
846 		mutex_unlock(&us->dev_mutex);
847 	}
848 	scsi_scan_host(us_to_host(us));
849 	dev_dbg(dev, "scan complete\n");
850 
851 	/* Should we unbind if no devices were detected? */
852 
853 	usb_autopm_put_interface(us->pusb_intf);
854 	clear_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
855 }
856 
857 static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf)
858 {
859 	struct usb_device *usb_dev = interface_to_usbdev(intf);
860 
861 	if (usb_dev->bus->sg_tablesize) {
862 		return usb_dev->bus->sg_tablesize;
863 	}
864 	return SG_ALL;
865 }
866 
867 /* First part of general USB mass-storage probing */
868 int usb_stor_probe1(struct us_data **pus,
869 		struct usb_interface *intf,
870 		const struct usb_device_id *id,
871 		struct us_unusual_dev *unusual_dev)
872 {
873 	struct Scsi_Host *host;
874 	struct us_data *us;
875 	int result;
876 
877 	US_DEBUGP("USB Mass Storage device detected\n");
878 
879 	/*
880 	 * Ask the SCSI layer to allocate a host structure, with extra
881 	 * space at the end for our private us_data structure.
882 	 */
883 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
884 	if (!host) {
885 		dev_warn(&intf->dev,
886 				"Unable to allocate the scsi host\n");
887 		return -ENOMEM;
888 	}
889 
890 	/*
891 	 * Allow 16-byte CDBs and thus > 2TB
892 	 */
893 	host->max_cmd_len = 16;
894 	host->sg_tablesize = usb_stor_sg_tablesize(intf);
895 	*pus = us = host_to_us(host);
896 	memset(us, 0, sizeof(struct us_data));
897 	mutex_init(&(us->dev_mutex));
898 	init_completion(&us->cmnd_ready);
899 	init_completion(&(us->notify));
900 	init_waitqueue_head(&us->delay_wait);
901 	INIT_DELAYED_WORK(&us->scan_dwork, usb_stor_scan_dwork);
902 
903 	/* Associate the us_data structure with the USB device */
904 	result = associate_dev(us, intf);
905 	if (result)
906 		goto BadDevice;
907 
908 	/* Get the unusual_devs entries and the descriptors */
909 	result = get_device_info(us, id, unusual_dev);
910 	if (result)
911 		goto BadDevice;
912 
913 	/* Get standard transport and protocol settings */
914 	get_transport(us);
915 	get_protocol(us);
916 
917 	/* Give the caller a chance to fill in specialized transport
918 	 * or protocol settings.
919 	 */
920 	return 0;
921 
922 BadDevice:
923 	US_DEBUGP("storage_probe() failed\n");
924 	release_everything(us);
925 	return result;
926 }
927 EXPORT_SYMBOL_GPL(usb_stor_probe1);
928 
929 /* Second part of general USB mass-storage probing */
930 int usb_stor_probe2(struct us_data *us)
931 {
932 	int result;
933 	struct device *dev = &us->pusb_intf->dev;
934 
935 	/* Make sure the transport and protocol have both been set */
936 	if (!us->transport || !us->proto_handler) {
937 		result = -ENXIO;
938 		goto BadDevice;
939 	}
940 	US_DEBUGP("Transport: %s\n", us->transport_name);
941 	US_DEBUGP("Protocol: %s\n", us->protocol_name);
942 
943 	/* fix for single-lun devices */
944 	if (us->fflags & US_FL_SINGLE_LUN)
945 		us->max_lun = 0;
946 
947 	/* Find the endpoints and calculate pipe values */
948 	result = get_pipes(us);
949 	if (result)
950 		goto BadDevice;
951 
952 	/*
953 	 * If the device returns invalid data for the first READ(10)
954 	 * command, indicate the command should be retried.
955 	 */
956 	if (us->fflags & US_FL_INITIAL_READ10)
957 		set_bit(US_FLIDX_REDO_READ10, &us->dflags);
958 
959 	/* Acquire all the other resources and add the host */
960 	result = usb_stor_acquire_resources(us);
961 	if (result)
962 		goto BadDevice;
963 	snprintf(us->scsi_name, sizeof(us->scsi_name), "usb-storage %s",
964 					dev_name(&us->pusb_intf->dev));
965 	result = scsi_add_host(us_to_host(us), dev);
966 	if (result) {
967 		dev_warn(dev,
968 				"Unable to add the scsi host\n");
969 		goto BadDevice;
970 	}
971 
972 	/* Submit the delayed_work for SCSI-device scanning */
973 	usb_autopm_get_interface_no_resume(us->pusb_intf);
974 	set_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
975 
976 	if (delay_use > 0)
977 		dev_dbg(dev, "waiting for device to settle before scanning\n");
978 	queue_delayed_work(system_freezable_wq, &us->scan_dwork,
979 			delay_use * HZ);
980 	return 0;
981 
982 	/* We come here if there are any problems */
983 BadDevice:
984 	US_DEBUGP("storage_probe() failed\n");
985 	release_everything(us);
986 	return result;
987 }
988 EXPORT_SYMBOL_GPL(usb_stor_probe2);
989 
990 /* Handle a USB mass-storage disconnect */
991 void usb_stor_disconnect(struct usb_interface *intf)
992 {
993 	struct us_data *us = usb_get_intfdata(intf);
994 
995 	US_DEBUGP("storage_disconnect() called\n");
996 	quiesce_and_remove_host(us);
997 	release_everything(us);
998 }
999 EXPORT_SYMBOL_GPL(usb_stor_disconnect);
1000 
1001 /* The main probe routine for standard devices */
1002 static int storage_probe(struct usb_interface *intf,
1003 			 const struct usb_device_id *id)
1004 {
1005 	struct us_unusual_dev *unusual_dev;
1006 	struct us_data *us;
1007 	int result;
1008 	int size;
1009 
1010 	/*
1011 	 * If libusual is configured, let it decide whether a standard
1012 	 * device should be handled by usb-storage or by ub.
1013 	 * If the device isn't standard (is handled by a subdriver
1014 	 * module) then don't accept it.
1015 	 */
1016 	if (usb_usual_check_type(id, USB_US_TYPE_STOR) ||
1017 			usb_usual_ignore_device(intf))
1018 		return -ENXIO;
1019 
1020 	/*
1021 	 * Call the general probe procedures.
1022 	 *
1023 	 * The unusual_dev_list array is parallel to the usb_storage_usb_ids
1024 	 * table, so we use the index of the id entry to find the
1025 	 * corresponding unusual_devs entry.
1026 	 */
1027 
1028 	size = ARRAY_SIZE(us_unusual_dev_list);
1029 	if (id >= usb_storage_usb_ids && id < usb_storage_usb_ids + size) {
1030 		unusual_dev = (id - usb_storage_usb_ids) + us_unusual_dev_list;
1031 	} else {
1032 		unusual_dev = &for_dynamic_ids;
1033 
1034 		US_DEBUGP("%s %s 0x%04x 0x%04x\n", "Use Bulk-Only transport",
1035 			"with the Transparent SCSI protocol for dynamic id:",
1036 			id->idVendor, id->idProduct);
1037 	}
1038 
1039 	result = usb_stor_probe1(&us, intf, id, unusual_dev);
1040 	if (result)
1041 		return result;
1042 
1043 	/* No special transport or protocol settings in the main module */
1044 
1045 	result = usb_stor_probe2(us);
1046 	return result;
1047 }
1048 
1049 /***********************************************************************
1050  * Initialization and registration
1051  ***********************************************************************/
1052 
1053 static struct usb_driver usb_storage_driver = {
1054 	.name =		"usb-storage",
1055 	.probe =	storage_probe,
1056 	.disconnect =	usb_stor_disconnect,
1057 	.suspend =	usb_stor_suspend,
1058 	.resume =	usb_stor_resume,
1059 	.reset_resume =	usb_stor_reset_resume,
1060 	.pre_reset =	usb_stor_pre_reset,
1061 	.post_reset =	usb_stor_post_reset,
1062 	.id_table =	usb_storage_usb_ids,
1063 	.supports_autosuspend = 1,
1064 	.soft_unbind =	1,
1065 };
1066 
1067 static int __init usb_stor_init(void)
1068 {
1069 	int retval;
1070 
1071 	pr_info("Initializing USB Mass Storage driver...\n");
1072 
1073 	/* register the driver, return usb_register return code if error */
1074 	retval = usb_register(&usb_storage_driver);
1075 	if (retval == 0) {
1076 		pr_info("USB Mass Storage support registered.\n");
1077 		usb_usual_set_present(USB_US_TYPE_STOR);
1078 	}
1079 	return retval;
1080 }
1081 
1082 static void __exit usb_stor_exit(void)
1083 {
1084 	US_DEBUGP("usb_stor_exit() called\n");
1085 
1086 	/* Deregister the driver
1087 	 * This will cause disconnect() to be called for each
1088 	 * attached unit
1089 	 */
1090 	US_DEBUGP("-- calling usb_deregister()\n");
1091 	usb_deregister(&usb_storage_driver) ;
1092 
1093 	usb_usual_clear_present(USB_US_TYPE_STOR);
1094 }
1095 
1096 module_init(usb_stor_init);
1097 module_exit(usb_stor_exit);
1098