xref: /linux/drivers/usb/storage/usb.c (revision e26207a3819684e9b4450a2d30bdd065fa92d9c7)
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 = 5;
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 #undef UNUSUAL_DEV
129 #undef COMPLIANT_DEV
130 #undef USUAL_DEV
131 
132 
133 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
134 
135 int usb_stor_suspend(struct usb_interface *iface, pm_message_t message)
136 {
137 	struct us_data *us = usb_get_intfdata(iface);
138 
139 	/* Wait until no command is running */
140 	mutex_lock(&us->dev_mutex);
141 
142 	US_DEBUGP("%s\n", __func__);
143 	if (us->suspend_resume_hook)
144 		(us->suspend_resume_hook)(us, US_SUSPEND);
145 
146 	/* When runtime PM is working, we'll set a flag to indicate
147 	 * whether we should autoresume when a SCSI request arrives. */
148 
149 	mutex_unlock(&us->dev_mutex);
150 	return 0;
151 }
152 EXPORT_SYMBOL_GPL(usb_stor_suspend);
153 
154 int usb_stor_resume(struct usb_interface *iface)
155 {
156 	struct us_data *us = usb_get_intfdata(iface);
157 
158 	mutex_lock(&us->dev_mutex);
159 
160 	US_DEBUGP("%s\n", __func__);
161 	if (us->suspend_resume_hook)
162 		(us->suspend_resume_hook)(us, US_RESUME);
163 
164 	mutex_unlock(&us->dev_mutex);
165 	return 0;
166 }
167 EXPORT_SYMBOL_GPL(usb_stor_resume);
168 
169 int usb_stor_reset_resume(struct usb_interface *iface)
170 {
171 	struct us_data *us = usb_get_intfdata(iface);
172 
173 	US_DEBUGP("%s\n", __func__);
174 
175 	/* Report the reset to the SCSI core */
176 	usb_stor_report_bus_reset(us);
177 
178 	/* FIXME: Notify the subdrivers that they need to reinitialize
179 	 * the device */
180 	return 0;
181 }
182 EXPORT_SYMBOL_GPL(usb_stor_reset_resume);
183 
184 #endif /* CONFIG_PM */
185 
186 /*
187  * The next two routines get called just before and just after
188  * a USB port reset, whether from this driver or a different one.
189  */
190 
191 int usb_stor_pre_reset(struct usb_interface *iface)
192 {
193 	struct us_data *us = usb_get_intfdata(iface);
194 
195 	US_DEBUGP("%s\n", __func__);
196 
197 	/* Make sure no command runs during the reset */
198 	mutex_lock(&us->dev_mutex);
199 	return 0;
200 }
201 EXPORT_SYMBOL_GPL(usb_stor_pre_reset);
202 
203 int usb_stor_post_reset(struct usb_interface *iface)
204 {
205 	struct us_data *us = usb_get_intfdata(iface);
206 
207 	US_DEBUGP("%s\n", __func__);
208 
209 	/* Report the reset to the SCSI core */
210 	usb_stor_report_bus_reset(us);
211 
212 	/* FIXME: Notify the subdrivers that they need to reinitialize
213 	 * the device */
214 
215 	mutex_unlock(&us->dev_mutex);
216 	return 0;
217 }
218 EXPORT_SYMBOL_GPL(usb_stor_post_reset);
219 
220 /*
221  * fill_inquiry_response takes an unsigned char array (which must
222  * be at least 36 characters) and populates the vendor name,
223  * product name, and revision fields. Then the array is copied
224  * into the SCSI command's response buffer (oddly enough
225  * called request_buffer). data_len contains the length of the
226  * data array, which again must be at least 36.
227  */
228 
229 void fill_inquiry_response(struct us_data *us, unsigned char *data,
230 		unsigned int data_len)
231 {
232 	if (data_len<36) // You lose.
233 		return;
234 
235 	memset(data+8, ' ', 28);
236 	if(data[0]&0x20) { /* USB device currently not connected. Return
237 			      peripheral qualifier 001b ("...however, the
238 			      physical device is not currently connected
239 			      to this logical unit") and leave vendor and
240 			      product identification empty. ("If the target
241 			      does store some of the INQUIRY data on the
242 			      device, it may return zeros or ASCII spaces
243 			      (20h) in those fields until the data is
244 			      available from the device."). */
245 	} else {
246 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
247 		int n;
248 
249 		n = strlen(us->unusual_dev->vendorName);
250 		memcpy(data+8, us->unusual_dev->vendorName, min(8, n));
251 		n = strlen(us->unusual_dev->productName);
252 		memcpy(data+16, us->unusual_dev->productName, min(16, n));
253 
254 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
255 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
256 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
257 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
258 	}
259 
260 	usb_stor_set_xfer_buf(data, data_len, us->srb);
261 }
262 EXPORT_SYMBOL_GPL(fill_inquiry_response);
263 
264 static int usb_stor_control_thread(void * __us)
265 {
266 	struct us_data *us = (struct us_data *)__us;
267 	struct Scsi_Host *host = us_to_host(us);
268 
269 	for(;;) {
270 		US_DEBUGP("*** thread sleeping.\n");
271 		if (wait_for_completion_interruptible(&us->cmnd_ready))
272 			break;
273 
274 		US_DEBUGP("*** thread awakened.\n");
275 
276 		/* lock the device pointers */
277 		mutex_lock(&(us->dev_mutex));
278 
279 		/* lock access to the state */
280 		scsi_lock(host);
281 
282 		/* When we are called with no command pending, we're done */
283 		if (us->srb == NULL) {
284 			scsi_unlock(host);
285 			mutex_unlock(&us->dev_mutex);
286 			US_DEBUGP("-- exiting\n");
287 			break;
288 		}
289 
290 		/* has the command timed out *already* ? */
291 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
292 			us->srb->result = DID_ABORT << 16;
293 			goto SkipForAbort;
294 		}
295 
296 		scsi_unlock(host);
297 
298 		/* reject the command if the direction indicator
299 		 * is UNKNOWN
300 		 */
301 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
302 			US_DEBUGP("UNKNOWN data direction\n");
303 			us->srb->result = DID_ERROR << 16;
304 		}
305 
306 		/* reject if target != 0 or if LUN is higher than
307 		 * the maximum known LUN
308 		 */
309 		else if (us->srb->device->id &&
310 				!(us->fflags & US_FL_SCM_MULT_TARG)) {
311 			US_DEBUGP("Bad target number (%d:%d)\n",
312 				  us->srb->device->id, us->srb->device->lun);
313 			us->srb->result = DID_BAD_TARGET << 16;
314 		}
315 
316 		else if (us->srb->device->lun > us->max_lun) {
317 			US_DEBUGP("Bad LUN (%d:%d)\n",
318 				  us->srb->device->id, us->srb->device->lun);
319 			us->srb->result = DID_BAD_TARGET << 16;
320 		}
321 
322 		/* Handle those devices which need us to fake
323 		 * their inquiry data */
324 		else if ((us->srb->cmnd[0] == INQUIRY) &&
325 			    (us->fflags & US_FL_FIX_INQUIRY)) {
326 			unsigned char data_ptr[36] = {
327 			    0x00, 0x80, 0x02, 0x02,
328 			    0x1F, 0x00, 0x00, 0x00};
329 
330 			US_DEBUGP("Faking INQUIRY command\n");
331 			fill_inquiry_response(us, data_ptr, 36);
332 			us->srb->result = SAM_STAT_GOOD;
333 		}
334 
335 		/* we've got a command, let's do it! */
336 		else {
337 			US_DEBUG(usb_stor_show_command(us->srb));
338 			us->proto_handler(us->srb, us);
339 		}
340 
341 		/* lock access to the state */
342 		scsi_lock(host);
343 
344 		/* indicate that the command is done */
345 		if (us->srb->result != DID_ABORT << 16) {
346 			US_DEBUGP("scsi cmd done, result=0x%x\n",
347 				   us->srb->result);
348 			us->srb->scsi_done(us->srb);
349 		} else {
350 SkipForAbort:
351 			US_DEBUGP("scsi command aborted\n");
352 		}
353 
354 		/* If an abort request was received we need to signal that
355 		 * the abort has finished.  The proper test for this is
356 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
357 		 * the timeout might have occurred after the command had
358 		 * already completed with a different result code. */
359 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
360 			complete(&(us->notify));
361 
362 			/* Allow USB transfers to resume */
363 			clear_bit(US_FLIDX_ABORTING, &us->dflags);
364 			clear_bit(US_FLIDX_TIMED_OUT, &us->dflags);
365 		}
366 
367 		/* finished working on this command */
368 		us->srb = NULL;
369 		scsi_unlock(host);
370 
371 		/* unlock the device pointers */
372 		mutex_unlock(&us->dev_mutex);
373 	} /* for (;;) */
374 
375 	/* Wait until we are told to stop */
376 	for (;;) {
377 		set_current_state(TASK_INTERRUPTIBLE);
378 		if (kthread_should_stop())
379 			break;
380 		schedule();
381 	}
382 	__set_current_state(TASK_RUNNING);
383 	return 0;
384 }
385 
386 /***********************************************************************
387  * Device probing and disconnecting
388  ***********************************************************************/
389 
390 /* Associate our private data with the USB device */
391 static int associate_dev(struct us_data *us, struct usb_interface *intf)
392 {
393 	US_DEBUGP("-- %s\n", __func__);
394 
395 	/* Fill in the device-related fields */
396 	us->pusb_dev = interface_to_usbdev(intf);
397 	us->pusb_intf = intf;
398 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
399 	US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
400 			le16_to_cpu(us->pusb_dev->descriptor.idVendor),
401 			le16_to_cpu(us->pusb_dev->descriptor.idProduct),
402 			le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
403 	US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
404 			intf->cur_altsetting->desc.bInterfaceSubClass,
405 			intf->cur_altsetting->desc.bInterfaceProtocol);
406 
407 	/* Store our private data in the interface */
408 	usb_set_intfdata(intf, us);
409 
410 	/* Allocate the device-related DMA-mapped buffers */
411 	us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
412 			GFP_KERNEL, &us->cr_dma);
413 	if (!us->cr) {
414 		US_DEBUGP("usb_ctrlrequest allocation failed\n");
415 		return -ENOMEM;
416 	}
417 
418 	us->iobuf = usb_buffer_alloc(us->pusb_dev, US_IOBUF_SIZE,
419 			GFP_KERNEL, &us->iobuf_dma);
420 	if (!us->iobuf) {
421 		US_DEBUGP("I/O buffer allocation failed\n");
422 		return -ENOMEM;
423 	}
424 	return 0;
425 }
426 
427 /* Works only for digits and letters, but small and fast */
428 #define TOLOWER(x) ((x) | 0x20)
429 
430 /* Adjust device flags based on the "quirks=" module parameter */
431 static void adjust_quirks(struct us_data *us)
432 {
433 	char *p;
434 	u16 vid = le16_to_cpu(us->pusb_dev->descriptor.idVendor);
435 	u16 pid = le16_to_cpu(us->pusb_dev->descriptor.idProduct);
436 	unsigned f = 0;
437 	unsigned int mask = (US_FL_SANE_SENSE | US_FL_BAD_SENSE |
438 			US_FL_FIX_CAPACITY |
439 			US_FL_CAPACITY_HEURISTICS | US_FL_IGNORE_DEVICE |
440 			US_FL_NOT_LOCKABLE | US_FL_MAX_SECTORS_64 |
441 			US_FL_CAPACITY_OK | US_FL_IGNORE_RESIDUE |
442 			US_FL_SINGLE_LUN | US_FL_NO_WP_DETECT);
443 
444 	p = quirks;
445 	while (*p) {
446 		/* Each entry consists of VID:PID:flags */
447 		if (vid == simple_strtoul(p, &p, 16) &&
448 				*p == ':' &&
449 				pid == simple_strtoul(p+1, &p, 16) &&
450 				*p == ':')
451 			break;
452 
453 		/* Move forward to the next entry */
454 		while (*p) {
455 			if (*p++ == ',')
456 				break;
457 		}
458 	}
459 	if (!*p)	/* No match */
460 		return;
461 
462 	/* Collect the flags */
463 	while (*++p && *p != ',') {
464 		switch (TOLOWER(*p)) {
465 		case 'a':
466 			f |= US_FL_SANE_SENSE;
467 			break;
468 		case 'b':
469 			f |= US_FL_BAD_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 }
602 
603 /* Get the protocol settings */
604 static void get_protocol(struct us_data *us)
605 {
606 	switch (us->subclass) {
607 	case US_SC_RBC:
608 		us->protocol_name = "Reduced Block Commands (RBC)";
609 		us->proto_handler = usb_stor_transparent_scsi_command;
610 		break;
611 
612 	case US_SC_8020:
613 		us->protocol_name = "8020i";
614 		us->proto_handler = usb_stor_pad12_command;
615 		us->max_lun = 0;
616 		break;
617 
618 	case US_SC_QIC:
619 		us->protocol_name = "QIC-157";
620 		us->proto_handler = usb_stor_pad12_command;
621 		us->max_lun = 0;
622 		break;
623 
624 	case US_SC_8070:
625 		us->protocol_name = "8070i";
626 		us->proto_handler = usb_stor_pad12_command;
627 		us->max_lun = 0;
628 		break;
629 
630 	case US_SC_SCSI:
631 		us->protocol_name = "Transparent SCSI";
632 		us->proto_handler = usb_stor_transparent_scsi_command;
633 		break;
634 
635 	case US_SC_UFI:
636 		us->protocol_name = "Uniform Floppy Interface (UFI)";
637 		us->proto_handler = usb_stor_ufi_command;
638 		break;
639 	}
640 }
641 
642 /* Get the pipe settings */
643 static int get_pipes(struct us_data *us)
644 {
645 	struct usb_host_interface *altsetting =
646 		us->pusb_intf->cur_altsetting;
647 	int i;
648 	struct usb_endpoint_descriptor *ep;
649 	struct usb_endpoint_descriptor *ep_in = NULL;
650 	struct usb_endpoint_descriptor *ep_out = NULL;
651 	struct usb_endpoint_descriptor *ep_int = NULL;
652 
653 	/*
654 	 * Find the first endpoint of each type we need.
655 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
656 	 * An optional interrupt-in is OK (necessary for CBI protocol).
657 	 * We will ignore any others.
658 	 */
659 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
660 		ep = &altsetting->endpoint[i].desc;
661 
662 		if (usb_endpoint_xfer_bulk(ep)) {
663 			if (usb_endpoint_dir_in(ep)) {
664 				if (!ep_in)
665 					ep_in = ep;
666 			} else {
667 				if (!ep_out)
668 					ep_out = ep;
669 			}
670 		}
671 
672 		else if (usb_endpoint_is_int_in(ep)) {
673 			if (!ep_int)
674 				ep_int = ep;
675 		}
676 	}
677 
678 	if (!ep_in || !ep_out || (us->protocol == US_PR_CBI && !ep_int)) {
679 		US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
680 		return -EIO;
681 	}
682 
683 	/* Calculate and store the pipe values */
684 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
685 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
686 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
687 		usb_endpoint_num(ep_out));
688 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
689 		usb_endpoint_num(ep_in));
690 	if (ep_int) {
691 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
692 			usb_endpoint_num(ep_int));
693 		us->ep_bInterval = ep_int->bInterval;
694 	}
695 	return 0;
696 }
697 
698 /* Initialize all the dynamic resources we need */
699 static int usb_stor_acquire_resources(struct us_data *us)
700 {
701 	int p;
702 	struct task_struct *th;
703 
704 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
705 	if (!us->current_urb) {
706 		US_DEBUGP("URB allocation failed\n");
707 		return -ENOMEM;
708 	}
709 
710 	/* Just before we start our control thread, initialize
711 	 * the device if it needs initialization */
712 	if (us->unusual_dev->initFunction) {
713 		p = us->unusual_dev->initFunction(us);
714 		if (p)
715 			return p;
716 	}
717 
718 	/* Start up our control thread */
719 	th = kthread_run(usb_stor_control_thread, us, "usb-storage");
720 	if (IS_ERR(th)) {
721 		printk(KERN_WARNING USB_STORAGE
722 		       "Unable to start control thread\n");
723 		return PTR_ERR(th);
724 	}
725 	us->ctl_thread = th;
726 
727 	return 0;
728 }
729 
730 /* Release all our dynamic resources */
731 static void usb_stor_release_resources(struct us_data *us)
732 {
733 	US_DEBUGP("-- %s\n", __func__);
734 
735 	/* Tell the control thread to exit.  The SCSI host must
736 	 * already have been removed and the DISCONNECTING flag set
737 	 * so that we won't accept any more commands.
738 	 */
739 	US_DEBUGP("-- sending exit command to thread\n");
740 	complete(&us->cmnd_ready);
741 	if (us->ctl_thread)
742 		kthread_stop(us->ctl_thread);
743 
744 	/* Call the destructor routine, if it exists */
745 	if (us->extra_destructor) {
746 		US_DEBUGP("-- calling extra_destructor()\n");
747 		us->extra_destructor(us->extra);
748 	}
749 
750 	/* Free the extra data and the URB */
751 	kfree(us->extra);
752 	usb_free_urb(us->current_urb);
753 }
754 
755 /* Dissociate from the USB device */
756 static void dissociate_dev(struct us_data *us)
757 {
758 	US_DEBUGP("-- %s\n", __func__);
759 
760 	/* Free the device-related DMA-mapped buffers */
761 	if (us->cr)
762 		usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
763 				us->cr_dma);
764 	if (us->iobuf)
765 		usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
766 				us->iobuf_dma);
767 
768 	/* Remove our private data from the interface */
769 	usb_set_intfdata(us->pusb_intf, NULL);
770 }
771 
772 /* First stage of disconnect processing: stop SCSI scanning,
773  * remove the host, and stop accepting new commands
774  */
775 static void quiesce_and_remove_host(struct us_data *us)
776 {
777 	struct Scsi_Host *host = us_to_host(us);
778 
779 	/* If the device is really gone, cut short reset delays */
780 	if (us->pusb_dev->state == USB_STATE_NOTATTACHED)
781 		set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
782 
783 	/* Prevent SCSI-scanning (if it hasn't started yet)
784 	 * and wait for the SCSI-scanning thread to stop.
785 	 */
786 	set_bit(US_FLIDX_DONT_SCAN, &us->dflags);
787 	wake_up(&us->delay_wait);
788 	wait_for_completion(&us->scanning_done);
789 
790 	/* Removing the host will perform an orderly shutdown: caches
791 	 * synchronized, disks spun down, etc.
792 	 */
793 	scsi_remove_host(host);
794 
795 	/* Prevent any new commands from being accepted and cut short
796 	 * reset delays.
797 	 */
798 	scsi_lock(host);
799 	set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
800 	scsi_unlock(host);
801 	wake_up(&us->delay_wait);
802 }
803 
804 /* Second stage of disconnect processing: deallocate all resources */
805 static void release_everything(struct us_data *us)
806 {
807 	usb_stor_release_resources(us);
808 	dissociate_dev(us);
809 
810 	/* Drop our reference to the host; the SCSI core will free it
811 	 * (and "us" along with it) when the refcount becomes 0. */
812 	scsi_host_put(us_to_host(us));
813 }
814 
815 /* Thread to carry out delayed SCSI-device scanning */
816 static int usb_stor_scan_thread(void * __us)
817 {
818 	struct us_data *us = (struct us_data *)__us;
819 
820 	dev_dbg(&us->pusb_intf->dev, "device found\n");
821 
822 	set_freezable();
823 	/* Wait for the timeout to expire or for a disconnect */
824 	if (delay_use > 0) {
825 		dev_dbg(&us->pusb_intf->dev, "waiting for device to settle "
826 				"before scanning\n");
827 		wait_event_freezable_timeout(us->delay_wait,
828 				test_bit(US_FLIDX_DONT_SCAN, &us->dflags),
829 				delay_use * HZ);
830 	}
831 
832 	/* If the device is still connected, perform the scanning */
833 	if (!test_bit(US_FLIDX_DONT_SCAN, &us->dflags)) {
834 
835 		/* For bulk-only devices, determine the max LUN value */
836 		if (us->protocol == US_PR_BULK &&
837 				!(us->fflags & US_FL_SINGLE_LUN)) {
838 			mutex_lock(&us->dev_mutex);
839 			us->max_lun = usb_stor_Bulk_max_lun(us);
840 			mutex_unlock(&us->dev_mutex);
841 		}
842 		scsi_scan_host(us_to_host(us));
843 		dev_dbg(&us->pusb_intf->dev, "scan complete\n");
844 
845 		/* Should we unbind if no devices were detected? */
846 	}
847 
848 	complete_and_exit(&us->scanning_done, 0);
849 }
850 
851 static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf)
852 {
853 	struct usb_device *usb_dev = interface_to_usbdev(intf);
854 
855 	if (usb_dev->bus->sg_tablesize) {
856 		return usb_dev->bus->sg_tablesize;
857 	}
858 	return SG_ALL;
859 }
860 
861 /* First part of general USB mass-storage probing */
862 int usb_stor_probe1(struct us_data **pus,
863 		struct usb_interface *intf,
864 		const struct usb_device_id *id,
865 		struct us_unusual_dev *unusual_dev)
866 {
867 	struct Scsi_Host *host;
868 	struct us_data *us;
869 	int result;
870 
871 	US_DEBUGP("USB Mass Storage device detected\n");
872 
873 	/*
874 	 * Ask the SCSI layer to allocate a host structure, with extra
875 	 * space at the end for our private us_data structure.
876 	 */
877 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
878 	if (!host) {
879 		printk(KERN_WARNING USB_STORAGE
880 			"Unable to allocate the scsi host\n");
881 		return -ENOMEM;
882 	}
883 
884 	/*
885 	 * Allow 16-byte CDBs and thus > 2TB
886 	 */
887 	host->max_cmd_len = 16;
888 	host->sg_tablesize = usb_stor_sg_tablesize(intf);
889 	*pus = us = host_to_us(host);
890 	memset(us, 0, sizeof(struct us_data));
891 	mutex_init(&(us->dev_mutex));
892 	init_completion(&us->cmnd_ready);
893 	init_completion(&(us->notify));
894 	init_waitqueue_head(&us->delay_wait);
895 	init_completion(&us->scanning_done);
896 
897 	/* Associate the us_data structure with the USB device */
898 	result = associate_dev(us, intf);
899 	if (result)
900 		goto BadDevice;
901 
902 	/* Get the unusual_devs entries and the descriptors */
903 	result = get_device_info(us, id, unusual_dev);
904 	if (result)
905 		goto BadDevice;
906 
907 	/* Get standard transport and protocol settings */
908 	get_transport(us);
909 	get_protocol(us);
910 
911 	/* Give the caller a chance to fill in specialized transport
912 	 * or protocol settings.
913 	 */
914 	return 0;
915 
916 BadDevice:
917 	US_DEBUGP("storage_probe() failed\n");
918 	release_everything(us);
919 	return result;
920 }
921 EXPORT_SYMBOL_GPL(usb_stor_probe1);
922 
923 /* Second part of general USB mass-storage probing */
924 int usb_stor_probe2(struct us_data *us)
925 {
926 	struct task_struct *th;
927 	int result;
928 
929 	/* Make sure the transport and protocol have both been set */
930 	if (!us->transport || !us->proto_handler) {
931 		result = -ENXIO;
932 		goto BadDevice;
933 	}
934 	US_DEBUGP("Transport: %s\n", us->transport_name);
935 	US_DEBUGP("Protocol: %s\n", us->protocol_name);
936 
937 	/* fix for single-lun devices */
938 	if (us->fflags & US_FL_SINGLE_LUN)
939 		us->max_lun = 0;
940 
941 	/* Find the endpoints and calculate pipe values */
942 	result = get_pipes(us);
943 	if (result)
944 		goto BadDevice;
945 
946 	/* Acquire all the other resources and add the host */
947 	result = usb_stor_acquire_resources(us);
948 	if (result)
949 		goto BadDevice;
950 	snprintf(us->scsi_name, sizeof(us->scsi_name), "usb-storage %s",
951 					dev_name(&us->pusb_intf->dev));
952 	result = scsi_add_host(us_to_host(us), &us->pusb_intf->dev);
953 	if (result) {
954 		printk(KERN_WARNING USB_STORAGE
955 			"Unable to add the scsi host\n");
956 		goto BadDevice;
957 	}
958 
959 	/* Start up the thread for delayed SCSI-device scanning */
960 	th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
961 	if (IS_ERR(th)) {
962 		printk(KERN_WARNING USB_STORAGE
963 		       "Unable to start the device-scanning thread\n");
964 		complete(&us->scanning_done);
965 		quiesce_and_remove_host(us);
966 		result = PTR_ERR(th);
967 		goto BadDevice;
968 	}
969 
970 	wake_up_process(th);
971 
972 	return 0;
973 
974 	/* We come here if there are any problems */
975 BadDevice:
976 	US_DEBUGP("storage_probe() failed\n");
977 	release_everything(us);
978 	return result;
979 }
980 EXPORT_SYMBOL_GPL(usb_stor_probe2);
981 
982 /* Handle a USB mass-storage disconnect */
983 void usb_stor_disconnect(struct usb_interface *intf)
984 {
985 	struct us_data *us = usb_get_intfdata(intf);
986 
987 	US_DEBUGP("storage_disconnect() called\n");
988 	quiesce_and_remove_host(us);
989 	release_everything(us);
990 }
991 EXPORT_SYMBOL_GPL(usb_stor_disconnect);
992 
993 /* The main probe routine for standard devices */
994 static int storage_probe(struct usb_interface *intf,
995 			 const struct usb_device_id *id)
996 {
997 	struct us_data *us;
998 	int result;
999 
1000 	/*
1001 	 * If libusual is configured, let it decide whether a standard
1002 	 * device should be handled by usb-storage or by ub.
1003 	 * If the device isn't standard (is handled by a subdriver
1004 	 * module) then don't accept it.
1005 	 */
1006 	if (usb_usual_check_type(id, USB_US_TYPE_STOR) ||
1007 			usb_usual_ignore_device(intf))
1008 		return -ENXIO;
1009 
1010 	/*
1011 	 * Call the general probe procedures.
1012 	 *
1013 	 * The unusual_dev_list array is parallel to the usb_storage_usb_ids
1014 	 * table, so we use the index of the id entry to find the
1015 	 * corresponding unusual_devs entry.
1016 	 */
1017 	result = usb_stor_probe1(&us, intf, id,
1018 			(id - usb_storage_usb_ids) + us_unusual_dev_list);
1019 	if (result)
1020 		return result;
1021 
1022 	/* No special transport or protocol settings in the main module */
1023 
1024 	result = usb_stor_probe2(us);
1025 	return result;
1026 }
1027 
1028 /***********************************************************************
1029  * Initialization and registration
1030  ***********************************************************************/
1031 
1032 static struct usb_driver usb_storage_driver = {
1033 	.name =		"usb-storage",
1034 	.probe =	storage_probe,
1035 	.disconnect =	usb_stor_disconnect,
1036 	.suspend =	usb_stor_suspend,
1037 	.resume =	usb_stor_resume,
1038 	.reset_resume =	usb_stor_reset_resume,
1039 	.pre_reset =	usb_stor_pre_reset,
1040 	.post_reset =	usb_stor_post_reset,
1041 	.id_table =	usb_storage_usb_ids,
1042 	.soft_unbind =	1,
1043 };
1044 
1045 static int __init usb_stor_init(void)
1046 {
1047 	int retval;
1048 
1049 	printk(KERN_INFO "Initializing USB Mass Storage driver...\n");
1050 
1051 	/* register the driver, return usb_register return code if error */
1052 	retval = usb_register(&usb_storage_driver);
1053 	if (retval == 0) {
1054 		printk(KERN_INFO "USB Mass Storage support registered.\n");
1055 		usb_usual_set_present(USB_US_TYPE_STOR);
1056 	}
1057 	return retval;
1058 }
1059 
1060 static void __exit usb_stor_exit(void)
1061 {
1062 	US_DEBUGP("usb_stor_exit() called\n");
1063 
1064 	/* Deregister the driver
1065 	 * This will cause disconnect() to be called for each
1066 	 * attached unit
1067 	 */
1068 	US_DEBUGP("-- calling usb_deregister()\n");
1069 	usb_deregister(&usb_storage_driver) ;
1070 
1071 	usb_usual_clear_present(USB_US_TYPE_STOR);
1072 }
1073 
1074 module_init(usb_stor_init);
1075 module_exit(usb_stor_exit);
1076