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 #undef UNUSUAL_DEV
129 #undef COMPLIANT_DEV
130 #undef USUAL_DEV
131 
132 
133 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
134 
usb_stor_suspend(struct usb_interface * iface,pm_message_t message)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 
usb_stor_resume(struct usb_interface * iface)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 
usb_stor_reset_resume(struct usb_interface * iface)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 
usb_stor_pre_reset(struct usb_interface * iface)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 
usb_stor_post_reset(struct usb_interface * iface)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 
fill_inquiry_response(struct us_data * us,unsigned char * data,unsigned int data_len)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 
usb_stor_control_thread(void * __us)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 			usb_mark_last_busy(us->pusb_dev);
340 		}
341 
342 		/* lock access to the state */
343 		scsi_lock(host);
344 
345 		/* indicate that the command is done */
346 		if (us->srb->result != DID_ABORT << 16) {
347 			US_DEBUGP("scsi cmd done, result=0x%x\n",
348 				   us->srb->result);
349 			us->srb->scsi_done(us->srb);
350 		} else {
351 SkipForAbort:
352 			US_DEBUGP("scsi command aborted\n");
353 		}
354 
355 		/* If an abort request was received we need to signal that
356 		 * the abort has finished.  The proper test for this is
357 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
358 		 * the timeout might have occurred after the command had
359 		 * already completed with a different result code. */
360 		if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
361 			complete(&(us->notify));
362 
363 			/* Allow USB transfers to resume */
364 			clear_bit(US_FLIDX_ABORTING, &us->dflags);
365 			clear_bit(US_FLIDX_TIMED_OUT, &us->dflags);
366 		}
367 
368 		/* finished working on this command */
369 		us->srb = NULL;
370 		scsi_unlock(host);
371 
372 		/* unlock the device pointers */
373 		mutex_unlock(&us->dev_mutex);
374 	} /* for (;;) */
375 
376 	/* Wait until we are told to stop */
377 	for (;;) {
378 		set_current_state(TASK_INTERRUPTIBLE);
379 		if (kthread_should_stop())
380 			break;
381 		schedule();
382 	}
383 	__set_current_state(TASK_RUNNING);
384 	return 0;
385 }
386 
387 /***********************************************************************
388  * Device probing and disconnecting
389  ***********************************************************************/
390 
391 /* Associate our private data with the USB device */
associate_dev(struct us_data * us,struct usb_interface * intf)392 static int associate_dev(struct us_data *us, struct usb_interface *intf)
393 {
394 	US_DEBUGP("-- %s\n", __func__);
395 
396 	/* Fill in the device-related fields */
397 	us->pusb_dev = interface_to_usbdev(intf);
398 	us->pusb_intf = intf;
399 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
400 	US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
401 			le16_to_cpu(us->pusb_dev->descriptor.idVendor),
402 			le16_to_cpu(us->pusb_dev->descriptor.idProduct),
403 			le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
404 	US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
405 			intf->cur_altsetting->desc.bInterfaceSubClass,
406 			intf->cur_altsetting->desc.bInterfaceProtocol);
407 
408 	/* Store our private data in the interface */
409 	usb_set_intfdata(intf, us);
410 
411 	/* Allocate the control/setup and DMA-mapped buffers */
412 	us->cr = kmalloc(sizeof(*us->cr), GFP_KERNEL);
413 	if (!us->cr) {
414 		US_DEBUGP("usb_ctrlrequest allocation failed\n");
415 		return -ENOMEM;
416 	}
417 
418 	us->iobuf = usb_alloc_coherent(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 */
adjust_quirks(struct us_data * us)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 			US_FL_NO_READ_DISC_INFO | US_FL_NO_READ_CAPACITY_16 |
444 			US_FL_INITIAL_READ10);
445 
446 	p = quirks;
447 	while (*p) {
448 		/* Each entry consists of VID:PID:flags */
449 		if (vid == simple_strtoul(p, &p, 16) &&
450 				*p == ':' &&
451 				pid == simple_strtoul(p+1, &p, 16) &&
452 				*p == ':')
453 			break;
454 
455 		/* Move forward to the next entry */
456 		while (*p) {
457 			if (*p++ == ',')
458 				break;
459 		}
460 	}
461 	if (!*p)	/* No match */
462 		return;
463 
464 	/* Collect the flags */
465 	while (*++p && *p != ',') {
466 		switch (TOLOWER(*p)) {
467 		case 'a':
468 			f |= US_FL_SANE_SENSE;
469 			break;
470 		case 'b':
471 			f |= US_FL_BAD_SENSE;
472 			break;
473 		case 'c':
474 			f |= US_FL_FIX_CAPACITY;
475 			break;
476 		case 'd':
477 			f |= US_FL_NO_READ_DISC_INFO;
478 			break;
479 		case 'e':
480 			f |= US_FL_NO_READ_CAPACITY_16;
481 			break;
482 		case 'h':
483 			f |= US_FL_CAPACITY_HEURISTICS;
484 			break;
485 		case 'i':
486 			f |= US_FL_IGNORE_DEVICE;
487 			break;
488 		case 'l':
489 			f |= US_FL_NOT_LOCKABLE;
490 			break;
491 		case 'm':
492 			f |= US_FL_MAX_SECTORS_64;
493 			break;
494 		case 'n':
495 			f |= US_FL_INITIAL_READ10;
496 			break;
497 		case 'o':
498 			f |= US_FL_CAPACITY_OK;
499 			break;
500 		case 'r':
501 			f |= US_FL_IGNORE_RESIDUE;
502 			break;
503 		case 's':
504 			f |= US_FL_SINGLE_LUN;
505 			break;
506 		case 'w':
507 			f |= US_FL_NO_WP_DETECT;
508 			break;
509 		/* Ignore unrecognized flag characters */
510 		}
511 	}
512 	us->fflags = (us->fflags & ~mask) | f;
513 }
514 
515 /* Get the unusual_devs entries and the string descriptors */
get_device_info(struct us_data * us,const struct usb_device_id * id,struct us_unusual_dev * unusual_dev)516 static int get_device_info(struct us_data *us, const struct usb_device_id *id,
517 		struct us_unusual_dev *unusual_dev)
518 {
519 	struct usb_device *dev = us->pusb_dev;
520 	struct usb_interface_descriptor *idesc =
521 		&us->pusb_intf->cur_altsetting->desc;
522 	struct device *pdev = &us->pusb_intf->dev;
523 
524 	/* Store the entries */
525 	us->unusual_dev = unusual_dev;
526 	us->subclass = (unusual_dev->useProtocol == USB_SC_DEVICE) ?
527 			idesc->bInterfaceSubClass :
528 			unusual_dev->useProtocol;
529 	us->protocol = (unusual_dev->useTransport == USB_PR_DEVICE) ?
530 			idesc->bInterfaceProtocol :
531 			unusual_dev->useTransport;
532 	us->fflags = USB_US_ORIG_FLAGS(id->driver_info);
533 	adjust_quirks(us);
534 
535 	if (us->fflags & US_FL_IGNORE_DEVICE) {
536 		dev_info(pdev, "device ignored\n");
537 		return -ENODEV;
538 	}
539 
540 	/*
541 	 * This flag is only needed when we're in high-speed, so let's
542 	 * disable it if we're in full-speed
543 	 */
544 	if (dev->speed != USB_SPEED_HIGH)
545 		us->fflags &= ~US_FL_GO_SLOW;
546 
547 	if (us->fflags)
548 		dev_info(pdev, "Quirks match for vid %04x pid %04x: %lx\n",
549 				le16_to_cpu(dev->descriptor.idVendor),
550 				le16_to_cpu(dev->descriptor.idProduct),
551 				us->fflags);
552 
553 	/* Log a message if a non-generic unusual_dev entry contains an
554 	 * unnecessary subclass or protocol override.  This may stimulate
555 	 * reports from users that will help us remove unneeded entries
556 	 * from the unusual_devs.h table.
557 	 */
558 	if (id->idVendor || id->idProduct) {
559 		static const char *msgs[3] = {
560 			"an unneeded SubClass entry",
561 			"an unneeded Protocol entry",
562 			"unneeded SubClass and Protocol entries"};
563 		struct usb_device_descriptor *ddesc = &dev->descriptor;
564 		int msg = -1;
565 
566 		if (unusual_dev->useProtocol != USB_SC_DEVICE &&
567 			us->subclass == idesc->bInterfaceSubClass)
568 			msg += 1;
569 		if (unusual_dev->useTransport != USB_PR_DEVICE &&
570 			us->protocol == idesc->bInterfaceProtocol)
571 			msg += 2;
572 		if (msg >= 0 && !(us->fflags & US_FL_NEED_OVERRIDE))
573 			dev_notice(pdev, "This device "
574 					"(%04x,%04x,%04x S %02x P %02x)"
575 					" has %s in unusual_devs.h (kernel"
576 					" %s)\n"
577 					"   Please send a copy of this message to "
578 					"<linux-usb@vger.kernel.org> and "
579 					"<usb-storage@lists.one-eyed-alien.net>\n",
580 					le16_to_cpu(ddesc->idVendor),
581 					le16_to_cpu(ddesc->idProduct),
582 					le16_to_cpu(ddesc->bcdDevice),
583 					idesc->bInterfaceSubClass,
584 					idesc->bInterfaceProtocol,
585 					msgs[msg],
586 					utsname()->release);
587 	}
588 
589 	return 0;
590 }
591 
592 /* Get the transport settings */
get_transport(struct us_data * us)593 static void get_transport(struct us_data *us)
594 {
595 	switch (us->protocol) {
596 	case USB_PR_CB:
597 		us->transport_name = "Control/Bulk";
598 		us->transport = usb_stor_CB_transport;
599 		us->transport_reset = usb_stor_CB_reset;
600 		us->max_lun = 7;
601 		break;
602 
603 	case USB_PR_CBI:
604 		us->transport_name = "Control/Bulk/Interrupt";
605 		us->transport = usb_stor_CB_transport;
606 		us->transport_reset = usb_stor_CB_reset;
607 		us->max_lun = 7;
608 		break;
609 
610 	case USB_PR_BULK:
611 		us->transport_name = "Bulk";
612 		us->transport = usb_stor_Bulk_transport;
613 		us->transport_reset = usb_stor_Bulk_reset;
614 		break;
615 	}
616 }
617 
618 /* Get the protocol settings */
get_protocol(struct us_data * us)619 static void get_protocol(struct us_data *us)
620 {
621 	switch (us->subclass) {
622 	case USB_SC_RBC:
623 		us->protocol_name = "Reduced Block Commands (RBC)";
624 		us->proto_handler = usb_stor_transparent_scsi_command;
625 		break;
626 
627 	case USB_SC_8020:
628 		us->protocol_name = "8020i";
629 		us->proto_handler = usb_stor_pad12_command;
630 		us->max_lun = 0;
631 		break;
632 
633 	case USB_SC_QIC:
634 		us->protocol_name = "QIC-157";
635 		us->proto_handler = usb_stor_pad12_command;
636 		us->max_lun = 0;
637 		break;
638 
639 	case USB_SC_8070:
640 		us->protocol_name = "8070i";
641 		us->proto_handler = usb_stor_pad12_command;
642 		us->max_lun = 0;
643 		break;
644 
645 	case USB_SC_SCSI:
646 		us->protocol_name = "Transparent SCSI";
647 		us->proto_handler = usb_stor_transparent_scsi_command;
648 		break;
649 
650 	case USB_SC_UFI:
651 		us->protocol_name = "Uniform Floppy Interface (UFI)";
652 		us->proto_handler = usb_stor_ufi_command;
653 		break;
654 	}
655 }
656 
657 /* Get the pipe settings */
get_pipes(struct us_data * us)658 static int get_pipes(struct us_data *us)
659 {
660 	struct usb_host_interface *altsetting =
661 		us->pusb_intf->cur_altsetting;
662 	int i;
663 	struct usb_endpoint_descriptor *ep;
664 	struct usb_endpoint_descriptor *ep_in = NULL;
665 	struct usb_endpoint_descriptor *ep_out = NULL;
666 	struct usb_endpoint_descriptor *ep_int = NULL;
667 
668 	/*
669 	 * Find the first endpoint of each type we need.
670 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
671 	 * An optional interrupt-in is OK (necessary for CBI protocol).
672 	 * We will ignore any others.
673 	 */
674 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
675 		ep = &altsetting->endpoint[i].desc;
676 
677 		if (usb_endpoint_xfer_bulk(ep)) {
678 			if (usb_endpoint_dir_in(ep)) {
679 				if (!ep_in)
680 					ep_in = ep;
681 			} else {
682 				if (!ep_out)
683 					ep_out = ep;
684 			}
685 		}
686 
687 		else if (usb_endpoint_is_int_in(ep)) {
688 			if (!ep_int)
689 				ep_int = ep;
690 		}
691 	}
692 
693 	if (!ep_in || !ep_out || (us->protocol == USB_PR_CBI && !ep_int)) {
694 		US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
695 		return -EIO;
696 	}
697 
698 	/* Calculate and store the pipe values */
699 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
700 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
701 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
702 		usb_endpoint_num(ep_out));
703 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
704 		usb_endpoint_num(ep_in));
705 	if (ep_int) {
706 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
707 			usb_endpoint_num(ep_int));
708 		us->ep_bInterval = ep_int->bInterval;
709 	}
710 	return 0;
711 }
712 
713 /* Initialize all the dynamic resources we need */
usb_stor_acquire_resources(struct us_data * us)714 static int usb_stor_acquire_resources(struct us_data *us)
715 {
716 	int p;
717 	struct task_struct *th;
718 
719 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
720 	if (!us->current_urb) {
721 		US_DEBUGP("URB allocation failed\n");
722 		return -ENOMEM;
723 	}
724 
725 	/* Just before we start our control thread, initialize
726 	 * the device if it needs initialization */
727 	if (us->unusual_dev->initFunction) {
728 		p = us->unusual_dev->initFunction(us);
729 		if (p)
730 			return p;
731 	}
732 
733 	/* Start up our control thread */
734 	th = kthread_run(usb_stor_control_thread, us, "usb-storage");
735 	if (IS_ERR(th)) {
736 		dev_warn(&us->pusb_intf->dev,
737 				"Unable to start control thread\n");
738 		return PTR_ERR(th);
739 	}
740 	us->ctl_thread = th;
741 
742 	return 0;
743 }
744 
745 /* Release all our dynamic resources */
usb_stor_release_resources(struct us_data * us)746 static void usb_stor_release_resources(struct us_data *us)
747 {
748 	US_DEBUGP("-- %s\n", __func__);
749 
750 	/* Tell the control thread to exit.  The SCSI host must
751 	 * already have been removed and the DISCONNECTING flag set
752 	 * so that we won't accept any more commands.
753 	 */
754 	US_DEBUGP("-- sending exit command to thread\n");
755 	complete(&us->cmnd_ready);
756 	if (us->ctl_thread)
757 		kthread_stop(us->ctl_thread);
758 
759 	/* Call the destructor routine, if it exists */
760 	if (us->extra_destructor) {
761 		US_DEBUGP("-- calling extra_destructor()\n");
762 		us->extra_destructor(us->extra);
763 	}
764 
765 	/* Free the extra data and the URB */
766 	kfree(us->extra);
767 	usb_free_urb(us->current_urb);
768 }
769 
770 /* Dissociate from the USB device */
dissociate_dev(struct us_data * us)771 static void dissociate_dev(struct us_data *us)
772 {
773 	US_DEBUGP("-- %s\n", __func__);
774 
775 	/* Free the buffers */
776 	kfree(us->cr);
777 	usb_free_coherent(us->pusb_dev, US_IOBUF_SIZE, us->iobuf, us->iobuf_dma);
778 
779 	/* Remove our private data from the interface */
780 	usb_set_intfdata(us->pusb_intf, NULL);
781 }
782 
783 /* First stage of disconnect processing: stop SCSI scanning,
784  * remove the host, and stop accepting new commands
785  */
quiesce_and_remove_host(struct us_data * us)786 static void quiesce_and_remove_host(struct us_data *us)
787 {
788 	struct Scsi_Host *host = us_to_host(us);
789 
790 	/* If the device is really gone, cut short reset delays */
791 	if (us->pusb_dev->state == USB_STATE_NOTATTACHED) {
792 		set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
793 		wake_up(&us->delay_wait);
794 	}
795 
796 	/* Prevent SCSI scanning (if it hasn't started yet)
797 	 * or wait for the SCSI-scanning routine to stop.
798 	 */
799 	cancel_delayed_work_sync(&us->scan_dwork);
800 
801 	/* Balance autopm calls if scanning was cancelled */
802 	if (test_bit(US_FLIDX_SCAN_PENDING, &us->dflags))
803 		usb_autopm_put_interface_no_suspend(us->pusb_intf);
804 
805 	/* Removing the host will perform an orderly shutdown: caches
806 	 * synchronized, disks spun down, etc.
807 	 */
808 	scsi_remove_host(host);
809 
810 	/* Prevent any new commands from being accepted and cut short
811 	 * reset delays.
812 	 */
813 	scsi_lock(host);
814 	set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
815 	scsi_unlock(host);
816 	wake_up(&us->delay_wait);
817 }
818 
819 /* Second stage of disconnect processing: deallocate all resources */
release_everything(struct us_data * us)820 static void release_everything(struct us_data *us)
821 {
822 	usb_stor_release_resources(us);
823 	dissociate_dev(us);
824 
825 	/* Drop our reference to the host; the SCSI core will free it
826 	 * (and "us" along with it) when the refcount becomes 0. */
827 	scsi_host_put(us_to_host(us));
828 }
829 
830 /* Delayed-work routine to carry out SCSI-device scanning */
usb_stor_scan_dwork(struct work_struct * work)831 static void usb_stor_scan_dwork(struct work_struct *work)
832 {
833 	struct us_data *us = container_of(work, struct us_data,
834 			scan_dwork.work);
835 	struct device *dev = &us->pusb_intf->dev;
836 
837 	dev_dbg(dev, "starting scan\n");
838 
839 	/* For bulk-only devices, determine the max LUN value */
840 	if (us->protocol == USB_PR_BULK && !(us->fflags & US_FL_SINGLE_LUN)) {
841 		mutex_lock(&us->dev_mutex);
842 		us->max_lun = usb_stor_Bulk_max_lun(us);
843 		mutex_unlock(&us->dev_mutex);
844 	}
845 	scsi_scan_host(us_to_host(us));
846 	dev_dbg(dev, "scan complete\n");
847 
848 	/* Should we unbind if no devices were detected? */
849 
850 	usb_autopm_put_interface(us->pusb_intf);
851 	clear_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
852 }
853 
usb_stor_sg_tablesize(struct usb_interface * intf)854 static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf)
855 {
856 	struct usb_device *usb_dev = interface_to_usbdev(intf);
857 
858 	if (usb_dev->bus->sg_tablesize) {
859 		return usb_dev->bus->sg_tablesize;
860 	}
861 	return SG_ALL;
862 }
863 
864 /* First part of general USB mass-storage probing */
usb_stor_probe1(struct us_data ** pus,struct usb_interface * intf,const struct usb_device_id * id,struct us_unusual_dev * unusual_dev)865 int usb_stor_probe1(struct us_data **pus,
866 		struct usb_interface *intf,
867 		const struct usb_device_id *id,
868 		struct us_unusual_dev *unusual_dev)
869 {
870 	struct Scsi_Host *host;
871 	struct us_data *us;
872 	int result;
873 
874 	US_DEBUGP("USB Mass Storage device detected\n");
875 
876 	/*
877 	 * Ask the SCSI layer to allocate a host structure, with extra
878 	 * space at the end for our private us_data structure.
879 	 */
880 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
881 	if (!host) {
882 		dev_warn(&intf->dev,
883 				"Unable to allocate the scsi host\n");
884 		return -ENOMEM;
885 	}
886 
887 	/*
888 	 * Allow 16-byte CDBs and thus > 2TB
889 	 */
890 	host->max_cmd_len = 16;
891 	host->sg_tablesize = usb_stor_sg_tablesize(intf);
892 	*pus = us = host_to_us(host);
893 	memset(us, 0, sizeof(struct us_data));
894 	mutex_init(&(us->dev_mutex));
895 	init_completion(&us->cmnd_ready);
896 	init_completion(&(us->notify));
897 	init_waitqueue_head(&us->delay_wait);
898 	INIT_DELAYED_WORK(&us->scan_dwork, usb_stor_scan_dwork);
899 
900 	/* Associate the us_data structure with the USB device */
901 	result = associate_dev(us, intf);
902 	if (result)
903 		goto BadDevice;
904 
905 	/* Get the unusual_devs entries and the descriptors */
906 	result = get_device_info(us, id, unusual_dev);
907 	if (result)
908 		goto BadDevice;
909 
910 	/* Get standard transport and protocol settings */
911 	get_transport(us);
912 	get_protocol(us);
913 
914 	/* Give the caller a chance to fill in specialized transport
915 	 * or protocol settings.
916 	 */
917 	return 0;
918 
919 BadDevice:
920 	US_DEBUGP("storage_probe() failed\n");
921 	release_everything(us);
922 	return result;
923 }
924 EXPORT_SYMBOL_GPL(usb_stor_probe1);
925 
926 /* Second part of general USB mass-storage probing */
usb_stor_probe2(struct us_data * us)927 int usb_stor_probe2(struct us_data *us)
928 {
929 	int result;
930 	struct device *dev = &us->pusb_intf->dev;
931 
932 	/* Make sure the transport and protocol have both been set */
933 	if (!us->transport || !us->proto_handler) {
934 		result = -ENXIO;
935 		goto BadDevice;
936 	}
937 	US_DEBUGP("Transport: %s\n", us->transport_name);
938 	US_DEBUGP("Protocol: %s\n", us->protocol_name);
939 
940 	/* fix for single-lun devices */
941 	if (us->fflags & US_FL_SINGLE_LUN)
942 		us->max_lun = 0;
943 
944 	/* Find the endpoints and calculate pipe values */
945 	result = get_pipes(us);
946 	if (result)
947 		goto BadDevice;
948 
949 	/*
950 	 * If the device returns invalid data for the first READ(10)
951 	 * command, indicate the command should be retried.
952 	 */
953 	if (us->fflags & US_FL_INITIAL_READ10)
954 		set_bit(US_FLIDX_REDO_READ10, &us->dflags);
955 
956 	/* Acquire all the other resources and add the host */
957 	result = usb_stor_acquire_resources(us);
958 	if (result)
959 		goto BadDevice;
960 	snprintf(us->scsi_name, sizeof(us->scsi_name), "usb-storage %s",
961 					dev_name(&us->pusb_intf->dev));
962 	result = scsi_add_host(us_to_host(us), dev);
963 	if (result) {
964 		dev_warn(dev,
965 				"Unable to add the scsi host\n");
966 		goto BadDevice;
967 	}
968 
969 	/* Submit the delayed_work for SCSI-device scanning */
970 	usb_autopm_get_interface_no_resume(us->pusb_intf);
971 	set_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
972 
973 	if (delay_use > 0)
974 		dev_dbg(dev, "waiting for device to settle before scanning\n");
975 	queue_delayed_work(system_freezable_wq, &us->scan_dwork,
976 			delay_use * HZ);
977 	return 0;
978 
979 	/* We come here if there are any problems */
980 BadDevice:
981 	US_DEBUGP("storage_probe() failed\n");
982 	release_everything(us);
983 	return result;
984 }
985 EXPORT_SYMBOL_GPL(usb_stor_probe2);
986 
987 /* Handle a USB mass-storage disconnect */
usb_stor_disconnect(struct usb_interface * intf)988 void usb_stor_disconnect(struct usb_interface *intf)
989 {
990 	struct us_data *us = usb_get_intfdata(intf);
991 
992 	US_DEBUGP("storage_disconnect() called\n");
993 	quiesce_and_remove_host(us);
994 	release_everything(us);
995 }
996 EXPORT_SYMBOL_GPL(usb_stor_disconnect);
997 
998 /* The main probe routine for standard devices */
storage_probe(struct usb_interface * intf,const struct usb_device_id * id)999 static int storage_probe(struct usb_interface *intf,
1000 			 const struct usb_device_id *id)
1001 {
1002 	struct us_data *us;
1003 	int result;
1004 
1005 	/*
1006 	 * If libusual is configured, let it decide whether a standard
1007 	 * device should be handled by usb-storage or by ub.
1008 	 * If the device isn't standard (is handled by a subdriver
1009 	 * module) then don't accept it.
1010 	 */
1011 	if (usb_usual_check_type(id, USB_US_TYPE_STOR) ||
1012 			usb_usual_ignore_device(intf))
1013 		return -ENXIO;
1014 
1015 	/*
1016 	 * Call the general probe procedures.
1017 	 *
1018 	 * The unusual_dev_list array is parallel to the usb_storage_usb_ids
1019 	 * table, so we use the index of the id entry to find the
1020 	 * corresponding unusual_devs entry.
1021 	 */
1022 	result = usb_stor_probe1(&us, intf, id,
1023 			(id - usb_storage_usb_ids) + us_unusual_dev_list);
1024 	if (result)
1025 		return result;
1026 
1027 	/* No special transport or protocol settings in the main module */
1028 
1029 	result = usb_stor_probe2(us);
1030 	return result;
1031 }
1032 
1033 /***********************************************************************
1034  * Initialization and registration
1035  ***********************************************************************/
1036 
1037 static struct usb_driver usb_storage_driver = {
1038 	.name =		"usb-storage",
1039 	.probe =	storage_probe,
1040 	.disconnect =	usb_stor_disconnect,
1041 	.suspend =	usb_stor_suspend,
1042 	.resume =	usb_stor_resume,
1043 	.reset_resume =	usb_stor_reset_resume,
1044 	.pre_reset =	usb_stor_pre_reset,
1045 	.post_reset =	usb_stor_post_reset,
1046 	.id_table =	usb_storage_usb_ids,
1047 	.supports_autosuspend = 1,
1048 	.soft_unbind =	1,
1049 	.no_dynamic_id = 1,
1050 };
1051 
usb_stor_init(void)1052 static int __init usb_stor_init(void)
1053 {
1054 	int retval;
1055 
1056 	pr_info("Initializing USB Mass Storage driver...\n");
1057 
1058 	/* register the driver, return usb_register return code if error */
1059 	retval = usb_register(&usb_storage_driver);
1060 	if (retval == 0) {
1061 		pr_info("USB Mass Storage support registered.\n");
1062 		usb_usual_set_present(USB_US_TYPE_STOR);
1063 	}
1064 	return retval;
1065 }
1066 
usb_stor_exit(void)1067 static void __exit usb_stor_exit(void)
1068 {
1069 	US_DEBUGP("usb_stor_exit() called\n");
1070 
1071 	/* Deregister the driver
1072 	 * This will cause disconnect() to be called for each
1073 	 * attached unit
1074 	 */
1075 	US_DEBUGP("-- calling usb_deregister()\n");
1076 	usb_deregister(&usb_storage_driver) ;
1077 
1078 	usb_usual_clear_present(USB_US_TYPE_STOR);
1079 }
1080 
1081 module_init(usb_stor_init);
1082 module_exit(usb_stor_exit);
1083