xref: /openbmc/linux/drivers/usb/storage/usb.c (revision 62e7ca52)
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/slab.h>
57 #include <linux/kthread.h>
58 #include <linux/mutex.h>
59 #include <linux/utsname.h>
60 
61 #include <scsi/scsi.h>
62 #include <scsi/scsi_cmnd.h>
63 #include <scsi/scsi_device.h>
64 
65 #include "usb.h"
66 #include "scsiglue.h"
67 #include "transport.h"
68 #include "protocol.h"
69 #include "debug.h"
70 #include "initializers.h"
71 
72 #include "sierra_ms.h"
73 #include "option_ms.h"
74 
75 #if IS_ENABLED(CONFIG_USB_UAS)
76 #include "uas-detect.h"
77 #endif
78 
79 /* Some informational data */
80 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
81 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
82 MODULE_LICENSE("GPL");
83 
84 static unsigned int delay_use = 1;
85 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
86 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
87 
88 static char quirks[128];
89 module_param_string(quirks, quirks, sizeof(quirks), S_IRUGO | S_IWUSR);
90 MODULE_PARM_DESC(quirks, "supplemental list of device IDs and their quirks");
91 
92 
93 /*
94  * The entries in this table correspond, line for line,
95  * with the entries in usb_storage_usb_ids[], defined in usual-tables.c.
96  */
97 
98 /* The vendor name should be kept at eight characters or less, and
99  * the product name should be kept at 16 characters or less. If a device
100  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
101  * normally generated by a device thorugh the INQUIRY response will be
102  * taken from this list, and this is the reason for the above size
103  * restriction. However, if the flag is not present, then you
104  * are free to use as many characters as you like.
105  */
106 
107 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
108 		    vendor_name, product_name, use_protocol, use_transport, \
109 		    init_function, Flags) \
110 { \
111 	.vendorName = vendor_name,	\
112 	.productName = product_name,	\
113 	.useProtocol = use_protocol,	\
114 	.useTransport = use_transport,	\
115 	.initFunction = init_function,	\
116 }
117 
118 #define COMPLIANT_DEV	UNUSUAL_DEV
119 
120 #define USUAL_DEV(use_protocol, use_transport) \
121 { \
122 	.useProtocol = use_protocol,	\
123 	.useTransport = use_transport,	\
124 }
125 
126 #define UNUSUAL_VENDOR_INTF(idVendor, cl, sc, pr, \
127 		vendor_name, product_name, use_protocol, use_transport, \
128 		init_function, Flags) \
129 { \
130 	.vendorName = vendor_name,	\
131 	.productName = product_name,	\
132 	.useProtocol = use_protocol,	\
133 	.useTransport = use_transport,	\
134 	.initFunction = init_function,	\
135 }
136 
137 static struct us_unusual_dev us_unusual_dev_list[] = {
138 #	include "unusual_devs.h"
139 	{ }		/* Terminating entry */
140 };
141 
142 static struct us_unusual_dev for_dynamic_ids =
143 		USUAL_DEV(USB_SC_SCSI, USB_PR_BULK);
144 
145 #undef UNUSUAL_DEV
146 #undef COMPLIANT_DEV
147 #undef USUAL_DEV
148 #undef UNUSUAL_VENDOR_INTF
149 
150 #ifdef CONFIG_LOCKDEP
151 
152 static struct lock_class_key us_interface_key[USB_MAXINTERFACES];
153 
154 static void us_set_lock_class(struct mutex *mutex,
155 		struct usb_interface *intf)
156 {
157 	struct usb_device *udev = interface_to_usbdev(intf);
158 	struct usb_host_config *config = udev->actconfig;
159 	int i;
160 
161 	for (i = 0; i < config->desc.bNumInterfaces; i++) {
162 		if (config->interface[i] == intf)
163 			break;
164 	}
165 
166 	BUG_ON(i == config->desc.bNumInterfaces);
167 
168 	lockdep_set_class(mutex, &us_interface_key[i]);
169 }
170 
171 #else
172 
173 static void us_set_lock_class(struct mutex *mutex,
174 		struct usb_interface *intf)
175 {
176 }
177 
178 #endif
179 
180 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
181 
182 int usb_stor_suspend(struct usb_interface *iface, pm_message_t message)
183 {
184 	struct us_data *us = usb_get_intfdata(iface);
185 
186 	/* Wait until no command is running */
187 	mutex_lock(&us->dev_mutex);
188 
189 	if (us->suspend_resume_hook)
190 		(us->suspend_resume_hook)(us, US_SUSPEND);
191 
192 	/* When runtime PM is working, we'll set a flag to indicate
193 	 * whether we should autoresume when a SCSI request arrives. */
194 
195 	mutex_unlock(&us->dev_mutex);
196 	return 0;
197 }
198 EXPORT_SYMBOL_GPL(usb_stor_suspend);
199 
200 int usb_stor_resume(struct usb_interface *iface)
201 {
202 	struct us_data *us = usb_get_intfdata(iface);
203 
204 	mutex_lock(&us->dev_mutex);
205 
206 	if (us->suspend_resume_hook)
207 		(us->suspend_resume_hook)(us, US_RESUME);
208 
209 	mutex_unlock(&us->dev_mutex);
210 	return 0;
211 }
212 EXPORT_SYMBOL_GPL(usb_stor_resume);
213 
214 int usb_stor_reset_resume(struct usb_interface *iface)
215 {
216 	struct us_data *us = usb_get_intfdata(iface);
217 
218 	/* Report the reset to the SCSI core */
219 	usb_stor_report_bus_reset(us);
220 
221 	/* FIXME: Notify the subdrivers that they need to reinitialize
222 	 * the device */
223 	return 0;
224 }
225 EXPORT_SYMBOL_GPL(usb_stor_reset_resume);
226 
227 #endif /* CONFIG_PM */
228 
229 /*
230  * The next two routines get called just before and just after
231  * a USB port reset, whether from this driver or a different one.
232  */
233 
234 int usb_stor_pre_reset(struct usb_interface *iface)
235 {
236 	struct us_data *us = usb_get_intfdata(iface);
237 
238 	/* Make sure no command runs during the reset */
239 	mutex_lock(&us->dev_mutex);
240 	return 0;
241 }
242 EXPORT_SYMBOL_GPL(usb_stor_pre_reset);
243 
244 int usb_stor_post_reset(struct usb_interface *iface)
245 {
246 	struct us_data *us = usb_get_intfdata(iface);
247 
248 	/* Report the reset to the SCSI core */
249 	usb_stor_report_bus_reset(us);
250 
251 	/* FIXME: Notify the subdrivers that they need to reinitialize
252 	 * the device */
253 
254 	mutex_unlock(&us->dev_mutex);
255 	return 0;
256 }
257 EXPORT_SYMBOL_GPL(usb_stor_post_reset);
258 
259 /*
260  * fill_inquiry_response takes an unsigned char array (which must
261  * be at least 36 characters) and populates the vendor name,
262  * product name, and revision fields. Then the array is copied
263  * into the SCSI command's response buffer (oddly enough
264  * called request_buffer). data_len contains the length of the
265  * data array, which again must be at least 36.
266  */
267 
268 void fill_inquiry_response(struct us_data *us, unsigned char *data,
269 		unsigned int data_len)
270 {
271 	if (data_len < 36) /* You lose. */
272 		return;
273 
274 	memset(data+8, ' ', 28);
275 	if (data[0]&0x20) { /* USB device currently not connected. Return
276 			      peripheral qualifier 001b ("...however, the
277 			      physical device is not currently connected
278 			      to this logical unit") and leave vendor and
279 			      product identification empty. ("If the target
280 			      does store some of the INQUIRY data on the
281 			      device, it may return zeros or ASCII spaces
282 			      (20h) in those fields until the data is
283 			      available from the device."). */
284 	} else {
285 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
286 		int n;
287 
288 		n = strlen(us->unusual_dev->vendorName);
289 		memcpy(data+8, us->unusual_dev->vendorName, min(8, n));
290 		n = strlen(us->unusual_dev->productName);
291 		memcpy(data+16, us->unusual_dev->productName, min(16, n));
292 
293 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
294 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
295 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
296 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
297 	}
298 
299 	usb_stor_set_xfer_buf(data, data_len, us->srb);
300 }
301 EXPORT_SYMBOL_GPL(fill_inquiry_response);
302 
303 static int usb_stor_control_thread(void * __us)
304 {
305 	struct us_data *us = (struct us_data *)__us;
306 	struct Scsi_Host *host = us_to_host(us);
307 
308 	for (;;) {
309 		usb_stor_dbg(us, "*** thread sleeping\n");
310 		if (wait_for_completion_interruptible(&us->cmnd_ready))
311 			break;
312 
313 		usb_stor_dbg(us, "*** thread awakened\n");
314 
315 		/* lock the device pointers */
316 		mutex_lock(&(us->dev_mutex));
317 
318 		/* lock access to the state */
319 		scsi_lock(host);
320 
321 		/* When we are called with no command pending, we're done */
322 		if (us->srb == NULL) {
323 			scsi_unlock(host);
324 			mutex_unlock(&us->dev_mutex);
325 			usb_stor_dbg(us, "-- exiting\n");
326 			break;
327 		}
328 
329 		/* has the command timed out *already* ? */
330 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
331 			us->srb->result = DID_ABORT << 16;
332 			goto SkipForAbort;
333 		}
334 
335 		scsi_unlock(host);
336 
337 		/* reject the command if the direction indicator
338 		 * is UNKNOWN
339 		 */
340 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
341 			usb_stor_dbg(us, "UNKNOWN data direction\n");
342 			us->srb->result = DID_ERROR << 16;
343 		}
344 
345 		/* reject if target != 0 or if LUN is higher than
346 		 * the maximum known LUN
347 		 */
348 		else if (us->srb->device->id &&
349 				!(us->fflags & US_FL_SCM_MULT_TARG)) {
350 			usb_stor_dbg(us, "Bad target number (%d:%d)\n",
351 				     us->srb->device->id, us->srb->device->lun);
352 			us->srb->result = DID_BAD_TARGET << 16;
353 		}
354 
355 		else if (us->srb->device->lun > us->max_lun) {
356 			usb_stor_dbg(us, "Bad LUN (%d:%d)\n",
357 				     us->srb->device->id, us->srb->device->lun);
358 			us->srb->result = DID_BAD_TARGET << 16;
359 		}
360 
361 		/* Handle those devices which need us to fake
362 		 * their inquiry data */
363 		else if ((us->srb->cmnd[0] == INQUIRY) &&
364 			    (us->fflags & US_FL_FIX_INQUIRY)) {
365 			unsigned char data_ptr[36] = {
366 			    0x00, 0x80, 0x02, 0x02,
367 			    0x1F, 0x00, 0x00, 0x00};
368 
369 			usb_stor_dbg(us, "Faking INQUIRY command\n");
370 			fill_inquiry_response(us, data_ptr, 36);
371 			us->srb->result = SAM_STAT_GOOD;
372 		}
373 
374 		/* we've got a command, let's do it! */
375 		else {
376 			US_DEBUG(usb_stor_show_command(us, us->srb));
377 			us->proto_handler(us->srb, us);
378 			usb_mark_last_busy(us->pusb_dev);
379 		}
380 
381 		/* lock access to the state */
382 		scsi_lock(host);
383 
384 		/* indicate that the command is done */
385 		if (us->srb->result != DID_ABORT << 16) {
386 			usb_stor_dbg(us, "scsi cmd done, result=0x%x\n",
387 				     us->srb->result);
388 			us->srb->scsi_done(us->srb);
389 		} else {
390 SkipForAbort:
391 			usb_stor_dbg(us, "scsi command aborted\n");
392 		}
393 
394 		/* If an abort request was received we need to signal that
395 		 * the abort has finished.  The proper test for this is
396 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
397 		 * the timeout might have occurred after the command had
398 		 * already completed with a different result code. */
399 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
400 			complete(&(us->notify));
401 
402 			/* Allow USB transfers to resume */
403 			clear_bit(US_FLIDX_ABORTING, &us->dflags);
404 			clear_bit(US_FLIDX_TIMED_OUT, &us->dflags);
405 		}
406 
407 		/* finished working on this command */
408 		us->srb = NULL;
409 		scsi_unlock(host);
410 
411 		/* unlock the device pointers */
412 		mutex_unlock(&us->dev_mutex);
413 	} /* for (;;) */
414 
415 	/* Wait until we are told to stop */
416 	for (;;) {
417 		set_current_state(TASK_INTERRUPTIBLE);
418 		if (kthread_should_stop())
419 			break;
420 		schedule();
421 	}
422 	__set_current_state(TASK_RUNNING);
423 	return 0;
424 }
425 
426 /***********************************************************************
427  * Device probing and disconnecting
428  ***********************************************************************/
429 
430 /* Associate our private data with the USB device */
431 static int associate_dev(struct us_data *us, struct usb_interface *intf)
432 {
433 	/* Fill in the device-related fields */
434 	us->pusb_dev = interface_to_usbdev(intf);
435 	us->pusb_intf = intf;
436 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
437 	usb_stor_dbg(us, "Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
438 		     le16_to_cpu(us->pusb_dev->descriptor.idVendor),
439 		     le16_to_cpu(us->pusb_dev->descriptor.idProduct),
440 		     le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
441 	usb_stor_dbg(us, "Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
442 		     intf->cur_altsetting->desc.bInterfaceSubClass,
443 		     intf->cur_altsetting->desc.bInterfaceProtocol);
444 
445 	/* Store our private data in the interface */
446 	usb_set_intfdata(intf, us);
447 
448 	/* Allocate the control/setup and DMA-mapped buffers */
449 	us->cr = kmalloc(sizeof(*us->cr), GFP_KERNEL);
450 	if (!us->cr)
451 		return -ENOMEM;
452 
453 	us->iobuf = usb_alloc_coherent(us->pusb_dev, US_IOBUF_SIZE,
454 			GFP_KERNEL, &us->iobuf_dma);
455 	if (!us->iobuf) {
456 		usb_stor_dbg(us, "I/O buffer allocation failed\n");
457 		return -ENOMEM;
458 	}
459 	return 0;
460 }
461 
462 /* Works only for digits and letters, but small and fast */
463 #define TOLOWER(x) ((x) | 0x20)
464 
465 /* Adjust device flags based on the "quirks=" module parameter */
466 void usb_stor_adjust_quirks(struct usb_device *udev, unsigned long *fflags)
467 {
468 	char *p;
469 	u16 vid = le16_to_cpu(udev->descriptor.idVendor);
470 	u16 pid = le16_to_cpu(udev->descriptor.idProduct);
471 	unsigned f = 0;
472 	unsigned int mask = (US_FL_SANE_SENSE | US_FL_BAD_SENSE |
473 			US_FL_FIX_CAPACITY | US_FL_IGNORE_UAS |
474 			US_FL_CAPACITY_HEURISTICS | US_FL_IGNORE_DEVICE |
475 			US_FL_NOT_LOCKABLE | US_FL_MAX_SECTORS_64 |
476 			US_FL_CAPACITY_OK | US_FL_IGNORE_RESIDUE |
477 			US_FL_SINGLE_LUN | US_FL_NO_WP_DETECT |
478 			US_FL_NO_READ_DISC_INFO | US_FL_NO_READ_CAPACITY_16 |
479 			US_FL_INITIAL_READ10 | US_FL_WRITE_CACHE);
480 
481 	p = quirks;
482 	while (*p) {
483 		/* Each entry consists of VID:PID:flags */
484 		if (vid == simple_strtoul(p, &p, 16) &&
485 				*p == ':' &&
486 				pid == simple_strtoul(p+1, &p, 16) &&
487 				*p == ':')
488 			break;
489 
490 		/* Move forward to the next entry */
491 		while (*p) {
492 			if (*p++ == ',')
493 				break;
494 		}
495 	}
496 	if (!*p)	/* No match */
497 		return;
498 
499 	/* Collect the flags */
500 	while (*++p && *p != ',') {
501 		switch (TOLOWER(*p)) {
502 		case 'a':
503 			f |= US_FL_SANE_SENSE;
504 			break;
505 		case 'b':
506 			f |= US_FL_BAD_SENSE;
507 			break;
508 		case 'c':
509 			f |= US_FL_FIX_CAPACITY;
510 			break;
511 		case 'd':
512 			f |= US_FL_NO_READ_DISC_INFO;
513 			break;
514 		case 'e':
515 			f |= US_FL_NO_READ_CAPACITY_16;
516 			break;
517 		case 'h':
518 			f |= US_FL_CAPACITY_HEURISTICS;
519 			break;
520 		case 'i':
521 			f |= US_FL_IGNORE_DEVICE;
522 			break;
523 		case 'l':
524 			f |= US_FL_NOT_LOCKABLE;
525 			break;
526 		case 'm':
527 			f |= US_FL_MAX_SECTORS_64;
528 			break;
529 		case 'n':
530 			f |= US_FL_INITIAL_READ10;
531 			break;
532 		case 'o':
533 			f |= US_FL_CAPACITY_OK;
534 			break;
535 		case 'p':
536 			f |= US_FL_WRITE_CACHE;
537 			break;
538 		case 'r':
539 			f |= US_FL_IGNORE_RESIDUE;
540 			break;
541 		case 's':
542 			f |= US_FL_SINGLE_LUN;
543 			break;
544 		case 'u':
545 			f |= US_FL_IGNORE_UAS;
546 			break;
547 		case 'w':
548 			f |= US_FL_NO_WP_DETECT;
549 			break;
550 		/* Ignore unrecognized flag characters */
551 		}
552 	}
553 	*fflags = (*fflags & ~mask) | f;
554 }
555 EXPORT_SYMBOL_GPL(usb_stor_adjust_quirks);
556 
557 /* Get the unusual_devs entries and the string descriptors */
558 static int get_device_info(struct us_data *us, const struct usb_device_id *id,
559 		struct us_unusual_dev *unusual_dev)
560 {
561 	struct usb_device *dev = us->pusb_dev;
562 	struct usb_interface_descriptor *idesc =
563 		&us->pusb_intf->cur_altsetting->desc;
564 	struct device *pdev = &us->pusb_intf->dev;
565 
566 	/* Store the entries */
567 	us->unusual_dev = unusual_dev;
568 	us->subclass = (unusual_dev->useProtocol == USB_SC_DEVICE) ?
569 			idesc->bInterfaceSubClass :
570 			unusual_dev->useProtocol;
571 	us->protocol = (unusual_dev->useTransport == USB_PR_DEVICE) ?
572 			idesc->bInterfaceProtocol :
573 			unusual_dev->useTransport;
574 	us->fflags = id->driver_info;
575 	usb_stor_adjust_quirks(us->pusb_dev, &us->fflags);
576 
577 	if (us->fflags & US_FL_IGNORE_DEVICE) {
578 		dev_info(pdev, "device ignored\n");
579 		return -ENODEV;
580 	}
581 
582 	/*
583 	 * This flag is only needed when we're in high-speed, so let's
584 	 * disable it if we're in full-speed
585 	 */
586 	if (dev->speed != USB_SPEED_HIGH)
587 		us->fflags &= ~US_FL_GO_SLOW;
588 
589 	if (us->fflags)
590 		dev_info(pdev, "Quirks match for vid %04x pid %04x: %lx\n",
591 				le16_to_cpu(dev->descriptor.idVendor),
592 				le16_to_cpu(dev->descriptor.idProduct),
593 				us->fflags);
594 
595 	/* Log a message if a non-generic unusual_dev entry contains an
596 	 * unnecessary subclass or protocol override.  This may stimulate
597 	 * reports from users that will help us remove unneeded entries
598 	 * from the unusual_devs.h table.
599 	 */
600 	if (id->idVendor || id->idProduct) {
601 		static const char *msgs[3] = {
602 			"an unneeded SubClass entry",
603 			"an unneeded Protocol entry",
604 			"unneeded SubClass and Protocol entries"};
605 		struct usb_device_descriptor *ddesc = &dev->descriptor;
606 		int msg = -1;
607 
608 		if (unusual_dev->useProtocol != USB_SC_DEVICE &&
609 			us->subclass == idesc->bInterfaceSubClass)
610 			msg += 1;
611 		if (unusual_dev->useTransport != USB_PR_DEVICE &&
612 			us->protocol == idesc->bInterfaceProtocol)
613 			msg += 2;
614 		if (msg >= 0 && !(us->fflags & US_FL_NEED_OVERRIDE))
615 			dev_notice(pdev, "This device "
616 					"(%04x,%04x,%04x S %02x P %02x)"
617 					" has %s in unusual_devs.h (kernel"
618 					" %s)\n"
619 					"   Please send a copy of this message to "
620 					"<linux-usb@vger.kernel.org> and "
621 					"<usb-storage@lists.one-eyed-alien.net>\n",
622 					le16_to_cpu(ddesc->idVendor),
623 					le16_to_cpu(ddesc->idProduct),
624 					le16_to_cpu(ddesc->bcdDevice),
625 					idesc->bInterfaceSubClass,
626 					idesc->bInterfaceProtocol,
627 					msgs[msg],
628 					utsname()->release);
629 	}
630 
631 	return 0;
632 }
633 
634 /* Get the transport settings */
635 static void get_transport(struct us_data *us)
636 {
637 	switch (us->protocol) {
638 	case USB_PR_CB:
639 		us->transport_name = "Control/Bulk";
640 		us->transport = usb_stor_CB_transport;
641 		us->transport_reset = usb_stor_CB_reset;
642 		us->max_lun = 7;
643 		break;
644 
645 	case USB_PR_CBI:
646 		us->transport_name = "Control/Bulk/Interrupt";
647 		us->transport = usb_stor_CB_transport;
648 		us->transport_reset = usb_stor_CB_reset;
649 		us->max_lun = 7;
650 		break;
651 
652 	case USB_PR_BULK:
653 		us->transport_name = "Bulk";
654 		us->transport = usb_stor_Bulk_transport;
655 		us->transport_reset = usb_stor_Bulk_reset;
656 		break;
657 	}
658 }
659 
660 /* Get the protocol settings */
661 static void get_protocol(struct us_data *us)
662 {
663 	switch (us->subclass) {
664 	case USB_SC_RBC:
665 		us->protocol_name = "Reduced Block Commands (RBC)";
666 		us->proto_handler = usb_stor_transparent_scsi_command;
667 		break;
668 
669 	case USB_SC_8020:
670 		us->protocol_name = "8020i";
671 		us->proto_handler = usb_stor_pad12_command;
672 		us->max_lun = 0;
673 		break;
674 
675 	case USB_SC_QIC:
676 		us->protocol_name = "QIC-157";
677 		us->proto_handler = usb_stor_pad12_command;
678 		us->max_lun = 0;
679 		break;
680 
681 	case USB_SC_8070:
682 		us->protocol_name = "8070i";
683 		us->proto_handler = usb_stor_pad12_command;
684 		us->max_lun = 0;
685 		break;
686 
687 	case USB_SC_SCSI:
688 		us->protocol_name = "Transparent SCSI";
689 		us->proto_handler = usb_stor_transparent_scsi_command;
690 		break;
691 
692 	case USB_SC_UFI:
693 		us->protocol_name = "Uniform Floppy Interface (UFI)";
694 		us->proto_handler = usb_stor_ufi_command;
695 		break;
696 	}
697 }
698 
699 /* Get the pipe settings */
700 static int get_pipes(struct us_data *us)
701 {
702 	struct usb_host_interface *altsetting =
703 		us->pusb_intf->cur_altsetting;
704 	int i;
705 	struct usb_endpoint_descriptor *ep;
706 	struct usb_endpoint_descriptor *ep_in = NULL;
707 	struct usb_endpoint_descriptor *ep_out = NULL;
708 	struct usb_endpoint_descriptor *ep_int = NULL;
709 
710 	/*
711 	 * Find the first endpoint of each type we need.
712 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
713 	 * An optional interrupt-in is OK (necessary for CBI protocol).
714 	 * We will ignore any others.
715 	 */
716 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
717 		ep = &altsetting->endpoint[i].desc;
718 
719 		if (usb_endpoint_xfer_bulk(ep)) {
720 			if (usb_endpoint_dir_in(ep)) {
721 				if (!ep_in)
722 					ep_in = ep;
723 			} else {
724 				if (!ep_out)
725 					ep_out = ep;
726 			}
727 		}
728 
729 		else if (usb_endpoint_is_int_in(ep)) {
730 			if (!ep_int)
731 				ep_int = ep;
732 		}
733 	}
734 
735 	if (!ep_in || !ep_out || (us->protocol == USB_PR_CBI && !ep_int)) {
736 		usb_stor_dbg(us, "Endpoint sanity check failed! Rejecting dev.\n");
737 		return -EIO;
738 	}
739 
740 	/* Calculate and store the pipe values */
741 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
742 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
743 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
744 		usb_endpoint_num(ep_out));
745 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
746 		usb_endpoint_num(ep_in));
747 	if (ep_int) {
748 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
749 			usb_endpoint_num(ep_int));
750 		us->ep_bInterval = ep_int->bInterval;
751 	}
752 	return 0;
753 }
754 
755 /* Initialize all the dynamic resources we need */
756 static int usb_stor_acquire_resources(struct us_data *us)
757 {
758 	int p;
759 	struct task_struct *th;
760 
761 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
762 	if (!us->current_urb) {
763 		usb_stor_dbg(us, "URB allocation failed\n");
764 		return -ENOMEM;
765 	}
766 
767 	/* Just before we start our control thread, initialize
768 	 * the device if it needs initialization */
769 	if (us->unusual_dev->initFunction) {
770 		p = us->unusual_dev->initFunction(us);
771 		if (p)
772 			return p;
773 	}
774 
775 	/* Start up our control thread */
776 	th = kthread_run(usb_stor_control_thread, us, "usb-storage");
777 	if (IS_ERR(th)) {
778 		dev_warn(&us->pusb_intf->dev,
779 				"Unable to start control thread\n");
780 		return PTR_ERR(th);
781 	}
782 	us->ctl_thread = th;
783 
784 	return 0;
785 }
786 
787 /* Release all our dynamic resources */
788 static void usb_stor_release_resources(struct us_data *us)
789 {
790 	/* Tell the control thread to exit.  The SCSI host must
791 	 * already have been removed and the DISCONNECTING flag set
792 	 * so that we won't accept any more commands.
793 	 */
794 	usb_stor_dbg(us, "-- sending exit command to thread\n");
795 	complete(&us->cmnd_ready);
796 	if (us->ctl_thread)
797 		kthread_stop(us->ctl_thread);
798 
799 	/* Call the destructor routine, if it exists */
800 	if (us->extra_destructor) {
801 		usb_stor_dbg(us, "-- calling extra_destructor()\n");
802 		us->extra_destructor(us->extra);
803 	}
804 
805 	/* Free the extra data and the URB */
806 	kfree(us->extra);
807 	usb_free_urb(us->current_urb);
808 }
809 
810 /* Dissociate from the USB device */
811 static void dissociate_dev(struct us_data *us)
812 {
813 	/* Free the buffers */
814 	kfree(us->cr);
815 	usb_free_coherent(us->pusb_dev, US_IOBUF_SIZE, us->iobuf, us->iobuf_dma);
816 
817 	/* Remove our private data from the interface */
818 	usb_set_intfdata(us->pusb_intf, NULL);
819 }
820 
821 /* First stage of disconnect processing: stop SCSI scanning,
822  * remove the host, and stop accepting new commands
823  */
824 static void quiesce_and_remove_host(struct us_data *us)
825 {
826 	struct Scsi_Host *host = us_to_host(us);
827 
828 	/* If the device is really gone, cut short reset delays */
829 	if (us->pusb_dev->state == USB_STATE_NOTATTACHED) {
830 		set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
831 		wake_up(&us->delay_wait);
832 	}
833 
834 	/* Prevent SCSI scanning (if it hasn't started yet)
835 	 * or wait for the SCSI-scanning routine to stop.
836 	 */
837 	cancel_delayed_work_sync(&us->scan_dwork);
838 
839 	/* Balance autopm calls if scanning was cancelled */
840 	if (test_bit(US_FLIDX_SCAN_PENDING, &us->dflags))
841 		usb_autopm_put_interface_no_suspend(us->pusb_intf);
842 
843 	/* Removing the host will perform an orderly shutdown: caches
844 	 * synchronized, disks spun down, etc.
845 	 */
846 	scsi_remove_host(host);
847 
848 	/* Prevent any new commands from being accepted and cut short
849 	 * reset delays.
850 	 */
851 	scsi_lock(host);
852 	set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
853 	scsi_unlock(host);
854 	wake_up(&us->delay_wait);
855 }
856 
857 /* Second stage of disconnect processing: deallocate all resources */
858 static void release_everything(struct us_data *us)
859 {
860 	usb_stor_release_resources(us);
861 	dissociate_dev(us);
862 
863 	/* Drop our reference to the host; the SCSI core will free it
864 	 * (and "us" along with it) when the refcount becomes 0. */
865 	scsi_host_put(us_to_host(us));
866 }
867 
868 /* Delayed-work routine to carry out SCSI-device scanning */
869 static void usb_stor_scan_dwork(struct work_struct *work)
870 {
871 	struct us_data *us = container_of(work, struct us_data,
872 			scan_dwork.work);
873 	struct device *dev = &us->pusb_intf->dev;
874 
875 	dev_dbg(dev, "starting scan\n");
876 
877 	/* For bulk-only devices, determine the max LUN value */
878 	if (us->protocol == USB_PR_BULK && !(us->fflags & US_FL_SINGLE_LUN)) {
879 		mutex_lock(&us->dev_mutex);
880 		us->max_lun = usb_stor_Bulk_max_lun(us);
881 		mutex_unlock(&us->dev_mutex);
882 	}
883 	scsi_scan_host(us_to_host(us));
884 	dev_dbg(dev, "scan complete\n");
885 
886 	/* Should we unbind if no devices were detected? */
887 
888 	usb_autopm_put_interface(us->pusb_intf);
889 	clear_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
890 }
891 
892 static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf)
893 {
894 	struct usb_device *usb_dev = interface_to_usbdev(intf);
895 
896 	if (usb_dev->bus->sg_tablesize) {
897 		return usb_dev->bus->sg_tablesize;
898 	}
899 	return SG_ALL;
900 }
901 
902 /* First part of general USB mass-storage probing */
903 int usb_stor_probe1(struct us_data **pus,
904 		struct usb_interface *intf,
905 		const struct usb_device_id *id,
906 		struct us_unusual_dev *unusual_dev)
907 {
908 	struct Scsi_Host *host;
909 	struct us_data *us;
910 	int result;
911 
912 	dev_info(&intf->dev, "USB Mass Storage device detected\n");
913 
914 	/*
915 	 * Ask the SCSI layer to allocate a host structure, with extra
916 	 * space at the end for our private us_data structure.
917 	 */
918 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
919 	if (!host) {
920 		dev_warn(&intf->dev, "Unable to allocate the scsi host\n");
921 		return -ENOMEM;
922 	}
923 
924 	/*
925 	 * Allow 16-byte CDBs and thus > 2TB
926 	 */
927 	host->max_cmd_len = 16;
928 	host->sg_tablesize = usb_stor_sg_tablesize(intf);
929 	*pus = us = host_to_us(host);
930 	mutex_init(&(us->dev_mutex));
931 	us_set_lock_class(&us->dev_mutex, intf);
932 	init_completion(&us->cmnd_ready);
933 	init_completion(&(us->notify));
934 	init_waitqueue_head(&us->delay_wait);
935 	INIT_DELAYED_WORK(&us->scan_dwork, usb_stor_scan_dwork);
936 
937 	/* Associate the us_data structure with the USB device */
938 	result = associate_dev(us, intf);
939 	if (result)
940 		goto BadDevice;
941 
942 	/* Get the unusual_devs entries and the descriptors */
943 	result = get_device_info(us, id, unusual_dev);
944 	if (result)
945 		goto BadDevice;
946 
947 	/* Get standard transport and protocol settings */
948 	get_transport(us);
949 	get_protocol(us);
950 
951 	/* Give the caller a chance to fill in specialized transport
952 	 * or protocol settings.
953 	 */
954 	return 0;
955 
956 BadDevice:
957 	usb_stor_dbg(us, "storage_probe() failed\n");
958 	release_everything(us);
959 	return result;
960 }
961 EXPORT_SYMBOL_GPL(usb_stor_probe1);
962 
963 /* Second part of general USB mass-storage probing */
964 int usb_stor_probe2(struct us_data *us)
965 {
966 	int result;
967 	struct device *dev = &us->pusb_intf->dev;
968 
969 	/* Make sure the transport and protocol have both been set */
970 	if (!us->transport || !us->proto_handler) {
971 		result = -ENXIO;
972 		goto BadDevice;
973 	}
974 	usb_stor_dbg(us, "Transport: %s\n", us->transport_name);
975 	usb_stor_dbg(us, "Protocol: %s\n", us->protocol_name);
976 
977 	/* fix for single-lun devices */
978 	if (us->fflags & US_FL_SINGLE_LUN)
979 		us->max_lun = 0;
980 
981 	if (!(us->fflags & US_FL_SCM_MULT_TARG))
982 		us_to_host(us)->max_id = 1;
983 
984 	/* Find the endpoints and calculate pipe values */
985 	result = get_pipes(us);
986 	if (result)
987 		goto BadDevice;
988 
989 	/*
990 	 * If the device returns invalid data for the first READ(10)
991 	 * command, indicate the command should be retried.
992 	 */
993 	if (us->fflags & US_FL_INITIAL_READ10)
994 		set_bit(US_FLIDX_REDO_READ10, &us->dflags);
995 
996 	/* Acquire all the other resources and add the host */
997 	result = usb_stor_acquire_resources(us);
998 	if (result)
999 		goto BadDevice;
1000 	snprintf(us->scsi_name, sizeof(us->scsi_name), "usb-storage %s",
1001 					dev_name(&us->pusb_intf->dev));
1002 	result = scsi_add_host(us_to_host(us), dev);
1003 	if (result) {
1004 		dev_warn(dev,
1005 				"Unable to add the scsi host\n");
1006 		goto BadDevice;
1007 	}
1008 
1009 	/* Submit the delayed_work for SCSI-device scanning */
1010 	usb_autopm_get_interface_no_resume(us->pusb_intf);
1011 	set_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
1012 
1013 	if (delay_use > 0)
1014 		dev_dbg(dev, "waiting for device to settle before scanning\n");
1015 	queue_delayed_work(system_freezable_wq, &us->scan_dwork,
1016 			delay_use * HZ);
1017 	return 0;
1018 
1019 	/* We come here if there are any problems */
1020 BadDevice:
1021 	usb_stor_dbg(us, "storage_probe() failed\n");
1022 	release_everything(us);
1023 	return result;
1024 }
1025 EXPORT_SYMBOL_GPL(usb_stor_probe2);
1026 
1027 /* Handle a USB mass-storage disconnect */
1028 void usb_stor_disconnect(struct usb_interface *intf)
1029 {
1030 	struct us_data *us = usb_get_intfdata(intf);
1031 
1032 	quiesce_and_remove_host(us);
1033 	release_everything(us);
1034 }
1035 EXPORT_SYMBOL_GPL(usb_stor_disconnect);
1036 
1037 /* The main probe routine for standard devices */
1038 static int storage_probe(struct usb_interface *intf,
1039 			 const struct usb_device_id *id)
1040 {
1041 	struct us_unusual_dev *unusual_dev;
1042 	struct us_data *us;
1043 	int result;
1044 	int size;
1045 
1046 	/* If uas is enabled and this device can do uas then ignore it. */
1047 #if IS_ENABLED(CONFIG_USB_UAS)
1048 	if (uas_use_uas_driver(intf, id))
1049 		return -ENXIO;
1050 #endif
1051 
1052 	/*
1053 	 * If the device isn't standard (is handled by a subdriver
1054 	 * module) then don't accept it.
1055 	 */
1056 	if (usb_usual_ignore_device(intf))
1057 		return -ENXIO;
1058 
1059 	/*
1060 	 * Call the general probe procedures.
1061 	 *
1062 	 * The unusual_dev_list array is parallel to the usb_storage_usb_ids
1063 	 * table, so we use the index of the id entry to find the
1064 	 * corresponding unusual_devs entry.
1065 	 */
1066 
1067 	size = ARRAY_SIZE(us_unusual_dev_list);
1068 	if (id >= usb_storage_usb_ids && id < usb_storage_usb_ids + size) {
1069 		unusual_dev = (id - usb_storage_usb_ids) + us_unusual_dev_list;
1070 	} else {
1071 		unusual_dev = &for_dynamic_ids;
1072 
1073 		dev_dbg(&intf->dev, "Use Bulk-Only transport with the Transparent SCSI protocol for dynamic id: 0x%04x 0x%04x\n",
1074 			id->idVendor, id->idProduct);
1075 	}
1076 
1077 	result = usb_stor_probe1(&us, intf, id, unusual_dev);
1078 	if (result)
1079 		return result;
1080 
1081 	/* No special transport or protocol settings in the main module */
1082 
1083 	result = usb_stor_probe2(us);
1084 	return result;
1085 }
1086 
1087 static struct usb_driver usb_storage_driver = {
1088 	.name =		"usb-storage",
1089 	.probe =	storage_probe,
1090 	.disconnect =	usb_stor_disconnect,
1091 	.suspend =	usb_stor_suspend,
1092 	.resume =	usb_stor_resume,
1093 	.reset_resume =	usb_stor_reset_resume,
1094 	.pre_reset =	usb_stor_pre_reset,
1095 	.post_reset =	usb_stor_post_reset,
1096 	.id_table =	usb_storage_usb_ids,
1097 	.supports_autosuspend = 1,
1098 	.soft_unbind =	1,
1099 };
1100 
1101 module_usb_driver(usb_storage_driver);
1102