xref: /linux/drivers/usb/storage/usb.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
1 /* Driver for USB Mass Storage compliant devices
2  *
3  * $Id: usb.c,v 1.75 2002/04/22 03:39:43 mdharm Exp $
4  *
5  * Current development and maintenance by:
6  *   (c) 1999-2003 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
7  *
8  * Developed with the assistance of:
9  *   (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
10  *   (c) 2003 Alan Stern (stern@rowland.harvard.edu)
11  *
12  * Initial work by:
13  *   (c) 1999 Michael Gee (michael@linuxspecific.com)
14  *
15  * usb_device_id support by Adam J. Richter (adam@yggdrasil.com):
16  *   (c) 2000 Yggdrasil Computing, Inc.
17  *
18  * This driver is based on the 'USB Mass Storage Class' document. This
19  * describes in detail the protocol used to communicate with such
20  * devices.  Clearly, the designers had SCSI and ATAPI commands in
21  * mind when they created this document.  The commands are all very
22  * similar to commands in the SCSI-II and ATAPI specifications.
23  *
24  * It is important to note that in a number of cases this class
25  * exhibits class-specific exemptions from the USB specification.
26  * Notably the usage of NAK, STALL and ACK differs from the norm, in
27  * that they are used to communicate wait, failed and OK on commands.
28  *
29  * Also, for certain devices, the interrupt endpoint is used to convey
30  * status of a command.
31  *
32  * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
33  * information about this driver.
34  *
35  * This program is free software; you can redistribute it and/or modify it
36  * under the terms of the GNU General Public License as published by the
37  * Free Software Foundation; either version 2, or (at your option) any
38  * later version.
39  *
40  * This program is distributed in the hope that it will be useful, but
41  * WITHOUT ANY WARRANTY; without even the implied warranty of
42  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
43  * General Public License for more details.
44  *
45  * You should have received a copy of the GNU General Public License along
46  * with this program; if not, write to the Free Software Foundation, Inc.,
47  * 675 Mass Ave, Cambridge, MA 02139, USA.
48  */
49 
50 #include <linux/config.h>
51 #include <linux/sched.h>
52 #include <linux/errno.h>
53 #include <linux/suspend.h>
54 #include <linux/module.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #include <linux/kthread.h>
58 
59 #include <scsi/scsi.h>
60 #include <scsi/scsi_cmnd.h>
61 #include <scsi/scsi_device.h>
62 
63 #include "usb.h"
64 #include "scsiglue.h"
65 #include "transport.h"
66 #include "protocol.h"
67 #include "debug.h"
68 #include "initializers.h"
69 
70 #ifdef CONFIG_USB_STORAGE_USBAT
71 #include "shuttle_usbat.h"
72 #endif
73 #ifdef CONFIG_USB_STORAGE_SDDR09
74 #include "sddr09.h"
75 #endif
76 #ifdef CONFIG_USB_STORAGE_SDDR55
77 #include "sddr55.h"
78 #endif
79 #ifdef CONFIG_USB_STORAGE_DPCM
80 #include "dpcm.h"
81 #endif
82 #ifdef CONFIG_USB_STORAGE_FREECOM
83 #include "freecom.h"
84 #endif
85 #ifdef CONFIG_USB_STORAGE_ISD200
86 #include "isd200.h"
87 #endif
88 #ifdef CONFIG_USB_STORAGE_DATAFAB
89 #include "datafab.h"
90 #endif
91 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
92 #include "jumpshot.h"
93 #endif
94 #ifdef CONFIG_USB_STORAGE_ONETOUCH
95 #include "onetouch.h"
96 #endif
97 
98 /* Some informational data */
99 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
100 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
101 MODULE_LICENSE("GPL");
102 
103 static unsigned int delay_use = 5;
104 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
105 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
106 
107 
108 /* These are used to make sure the module doesn't unload before all the
109  * threads have exited.
110  */
111 static atomic_t total_threads = ATOMIC_INIT(0);
112 static DECLARE_COMPLETION(threads_gone);
113 
114 
115 /* The entries in this table, except for final ones here
116  * (USB_MASS_STORAGE_CLASS and the empty entry), correspond,
117  * line for line with the entries of us_unsuaul_dev_list[].
118  */
119 
120 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
121 		    vendorName, productName,useProtocol, useTransport, \
122 		    initFunction, flags) \
123 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin,bcdDeviceMax) }
124 
125 static struct usb_device_id storage_usb_ids [] = {
126 
127 #	include "unusual_devs.h"
128 #undef UNUSUAL_DEV
129 	/* Control/Bulk transport for all SubClass values */
130 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_RBC, US_PR_CB) },
131 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_8020, US_PR_CB) },
132 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_QIC, US_PR_CB) },
133 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_UFI, US_PR_CB) },
134 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_8070, US_PR_CB) },
135 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_CB) },
136 
137 	/* Control/Bulk/Interrupt transport for all SubClass values */
138 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_RBC, US_PR_CBI) },
139 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_8020, US_PR_CBI) },
140 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_QIC, US_PR_CBI) },
141 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_UFI, US_PR_CBI) },
142 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_8070, US_PR_CBI) },
143 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_CBI) },
144 
145 	/* Bulk-only transport for all SubClass values */
146 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_RBC, US_PR_BULK) },
147 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_8020, US_PR_BULK) },
148 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_QIC, US_PR_BULK) },
149 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_UFI, US_PR_BULK) },
150 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_8070, US_PR_BULK) },
151 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_BULK) },
152 
153 	/* Terminating entry */
154 	{ }
155 };
156 
157 MODULE_DEVICE_TABLE (usb, storage_usb_ids);
158 
159 /* This is the list of devices we recognize, along with their flag data */
160 
161 /* The vendor name should be kept at eight characters or less, and
162  * the product name should be kept at 16 characters or less. If a device
163  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
164  * normally generated by a device thorugh the INQUIRY response will be
165  * taken from this list, and this is the reason for the above size
166  * restriction. However, if the flag is not present, then you
167  * are free to use as many characters as you like.
168  */
169 
170 #undef UNUSUAL_DEV
171 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
172 		    vendor_name, product_name, use_protocol, use_transport, \
173 		    init_function, Flags) \
174 { \
175 	.vendorName = vendor_name,	\
176 	.productName = product_name,	\
177 	.useProtocol = use_protocol,	\
178 	.useTransport = use_transport,	\
179 	.initFunction = init_function,	\
180 	.flags = Flags, \
181 }
182 
183 static struct us_unusual_dev us_unusual_dev_list[] = {
184 #	include "unusual_devs.h"
185 #	undef UNUSUAL_DEV
186 	/* Control/Bulk transport for all SubClass values */
187 	{ .useProtocol = US_SC_RBC,
188 	  .useTransport = US_PR_CB},
189 	{ .useProtocol = US_SC_8020,
190 	  .useTransport = US_PR_CB},
191 	{ .useProtocol = US_SC_QIC,
192 	  .useTransport = US_PR_CB},
193 	{ .useProtocol = US_SC_UFI,
194 	  .useTransport = US_PR_CB},
195 	{ .useProtocol = US_SC_8070,
196 	  .useTransport = US_PR_CB},
197 	{ .useProtocol = US_SC_SCSI,
198 	  .useTransport = US_PR_CB},
199 
200 	/* Control/Bulk/Interrupt transport for all SubClass values */
201 	{ .useProtocol = US_SC_RBC,
202 	  .useTransport = US_PR_CBI},
203 	{ .useProtocol = US_SC_8020,
204 	  .useTransport = US_PR_CBI},
205 	{ .useProtocol = US_SC_QIC,
206 	  .useTransport = US_PR_CBI},
207 	{ .useProtocol = US_SC_UFI,
208 	  .useTransport = US_PR_CBI},
209 	{ .useProtocol = US_SC_8070,
210 	  .useTransport = US_PR_CBI},
211 	{ .useProtocol = US_SC_SCSI,
212 	  .useTransport = US_PR_CBI},
213 
214 	/* Bulk-only transport for all SubClass values */
215 	{ .useProtocol = US_SC_RBC,
216 	  .useTransport = US_PR_BULK},
217 	{ .useProtocol = US_SC_8020,
218 	  .useTransport = US_PR_BULK},
219 	{ .useProtocol = US_SC_QIC,
220 	  .useTransport = US_PR_BULK},
221 	{ .useProtocol = US_SC_UFI,
222 	  .useTransport = US_PR_BULK},
223 	{ .useProtocol = US_SC_8070,
224 	  .useTransport = US_PR_BULK},
225 	{ .useProtocol = US_SC_SCSI,
226 	  .useTransport = US_PR_BULK},
227 
228 	/* Terminating entry */
229 	{ NULL }
230 };
231 
232 
233 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
234 
235 static int storage_suspend(struct usb_interface *iface, pm_message_t message)
236 {
237 	struct us_data *us = usb_get_intfdata(iface);
238 
239 	/* Wait until no command is running */
240 	down(&us->dev_semaphore);
241 
242 	US_DEBUGP("%s\n", __FUNCTION__);
243 	iface->dev.power.power_state.event = message.event;
244 
245 	/* When runtime PM is working, we'll set a flag to indicate
246 	 * whether we should autoresume when a SCSI request arrives. */
247 
248 	up(&us->dev_semaphore);
249 	return 0;
250 }
251 
252 static int storage_resume(struct usb_interface *iface)
253 {
254 	struct us_data *us = usb_get_intfdata(iface);
255 
256 	down(&us->dev_semaphore);
257 
258 	US_DEBUGP("%s\n", __FUNCTION__);
259 	iface->dev.power.power_state.event = PM_EVENT_ON;
260 
261 	up(&us->dev_semaphore);
262 	return 0;
263 }
264 
265 #endif /* CONFIG_PM */
266 
267 /*
268  * fill_inquiry_response takes an unsigned char array (which must
269  * be at least 36 characters) and populates the vendor name,
270  * product name, and revision fields. Then the array is copied
271  * into the SCSI command's response buffer (oddly enough
272  * called request_buffer). data_len contains the length of the
273  * data array, which again must be at least 36.
274  */
275 
276 void fill_inquiry_response(struct us_data *us, unsigned char *data,
277 		unsigned int data_len)
278 {
279 	if (data_len<36) // You lose.
280 		return;
281 
282 	if(data[0]&0x20) { /* USB device currently not connected. Return
283 			      peripheral qualifier 001b ("...however, the
284 			      physical device is not currently connected
285 			      to this logical unit") and leave vendor and
286 			      product identification empty. ("If the target
287 			      does store some of the INQUIRY data on the
288 			      device, it may return zeros or ASCII spaces
289 			      (20h) in those fields until the data is
290 			      available from the device."). */
291 		memset(data+8,0,28);
292 	} else {
293 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
294 		memcpy(data+8, us->unusual_dev->vendorName,
295 			strlen(us->unusual_dev->vendorName) > 8 ? 8 :
296 			strlen(us->unusual_dev->vendorName));
297 		memcpy(data+16, us->unusual_dev->productName,
298 			strlen(us->unusual_dev->productName) > 16 ? 16 :
299 			strlen(us->unusual_dev->productName));
300 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
301 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
302 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
303 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
304 	}
305 
306 	usb_stor_set_xfer_buf(data, data_len, us->srb);
307 }
308 
309 static int usb_stor_control_thread(void * __us)
310 {
311 	struct us_data *us = (struct us_data *)__us;
312 	struct Scsi_Host *host = us_to_host(us);
313 
314 	current->flags |= PF_NOFREEZE;
315 
316 	for(;;) {
317 		US_DEBUGP("*** thread sleeping.\n");
318 		if(down_interruptible(&us->sema))
319 			break;
320 
321 		US_DEBUGP("*** thread awakened.\n");
322 
323 		/* lock the device pointers */
324 		down(&(us->dev_semaphore));
325 
326 		/* if the device has disconnected, we are free to exit */
327 		if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
328 			US_DEBUGP("-- exiting\n");
329 			up(&(us->dev_semaphore));
330 			break;
331 		}
332 
333 		/* lock access to the state */
334 		scsi_lock(host);
335 
336 		/* has the command timed out *already* ? */
337 		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
338 			us->srb->result = DID_ABORT << 16;
339 			goto SkipForAbort;
340 		}
341 
342 		scsi_unlock(host);
343 
344 		/* reject the command if the direction indicator
345 		 * is UNKNOWN
346 		 */
347 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
348 			US_DEBUGP("UNKNOWN data direction\n");
349 			us->srb->result = DID_ERROR << 16;
350 		}
351 
352 		/* reject if target != 0 or if LUN is higher than
353 		 * the maximum known LUN
354 		 */
355 		else if (us->srb->device->id &&
356 				!(us->flags & US_FL_SCM_MULT_TARG)) {
357 			US_DEBUGP("Bad target number (%d:%d)\n",
358 				  us->srb->device->id, us->srb->device->lun);
359 			us->srb->result = DID_BAD_TARGET << 16;
360 		}
361 
362 		else if (us->srb->device->lun > us->max_lun) {
363 			US_DEBUGP("Bad LUN (%d:%d)\n",
364 				  us->srb->device->id, us->srb->device->lun);
365 			us->srb->result = DID_BAD_TARGET << 16;
366 		}
367 
368 		/* Handle those devices which need us to fake
369 		 * their inquiry data */
370 		else if ((us->srb->cmnd[0] == INQUIRY) &&
371 			    (us->flags & US_FL_FIX_INQUIRY)) {
372 			unsigned char data_ptr[36] = {
373 			    0x00, 0x80, 0x02, 0x02,
374 			    0x1F, 0x00, 0x00, 0x00};
375 
376 			US_DEBUGP("Faking INQUIRY command\n");
377 			fill_inquiry_response(us, data_ptr, 36);
378 			us->srb->result = SAM_STAT_GOOD;
379 		}
380 
381 		/* we've got a command, let's do it! */
382 		else {
383 			US_DEBUG(usb_stor_show_command(us->srb));
384 			us->proto_handler(us->srb, us);
385 		}
386 
387 		/* lock access to the state */
388 		scsi_lock(host);
389 
390 		/* indicate that the command is done */
391 		if (us->srb->result != DID_ABORT << 16) {
392 			US_DEBUGP("scsi cmd done, result=0x%x\n",
393 				   us->srb->result);
394 			us->srb->scsi_done(us->srb);
395 		} else {
396 SkipForAbort:
397 			US_DEBUGP("scsi command aborted\n");
398 		}
399 
400 		/* If an abort request was received we need to signal that
401 		 * the abort has finished.  The proper test for this is
402 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
403 		 * the timeout might have occurred after the command had
404 		 * already completed with a different result code. */
405 		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
406 			complete(&(us->notify));
407 
408 			/* Allow USB transfers to resume */
409 			clear_bit(US_FLIDX_ABORTING, &us->flags);
410 			clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
411 		}
412 
413 		/* finished working on this command */
414 		us->srb = NULL;
415 		scsi_unlock(host);
416 
417 		/* unlock the device pointers */
418 		up(&(us->dev_semaphore));
419 	} /* for (;;) */
420 
421 	scsi_host_put(host);
422 
423 	/* notify the exit routine that we're actually exiting now
424 	 *
425 	 * complete()/wait_for_completion() is similar to up()/down(),
426 	 * except that complete() is safe in the case where the structure
427 	 * is getting deleted in a parallel mode of execution (i.e. just
428 	 * after the down() -- that's necessary for the thread-shutdown
429 	 * case.
430 	 *
431 	 * complete_and_exit() goes even further than this -- it is safe in
432 	 * the case that the thread of the caller is going away (not just
433 	 * the structure) -- this is necessary for the module-remove case.
434 	 * This is important in preemption kernels, which transfer the flow
435 	 * of execution immediately upon a complete().
436 	 */
437 	complete_and_exit(&threads_gone, 0);
438 }
439 
440 /***********************************************************************
441  * Device probing and disconnecting
442  ***********************************************************************/
443 
444 /* Associate our private data with the USB device */
445 static int associate_dev(struct us_data *us, struct usb_interface *intf)
446 {
447 	US_DEBUGP("-- %s\n", __FUNCTION__);
448 
449 	/* Fill in the device-related fields */
450 	us->pusb_dev = interface_to_usbdev(intf);
451 	us->pusb_intf = intf;
452 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
453 	US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
454 			le16_to_cpu(us->pusb_dev->descriptor.idVendor),
455 			le16_to_cpu(us->pusb_dev->descriptor.idProduct),
456 			le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
457 	US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
458 			intf->cur_altsetting->desc.bInterfaceSubClass,
459 			intf->cur_altsetting->desc.bInterfaceProtocol);
460 
461 	/* Store our private data in the interface */
462 	usb_set_intfdata(intf, us);
463 
464 	/* Allocate the device-related DMA-mapped buffers */
465 	us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
466 			GFP_KERNEL, &us->cr_dma);
467 	if (!us->cr) {
468 		US_DEBUGP("usb_ctrlrequest allocation failed\n");
469 		return -ENOMEM;
470 	}
471 
472 	us->iobuf = usb_buffer_alloc(us->pusb_dev, US_IOBUF_SIZE,
473 			GFP_KERNEL, &us->iobuf_dma);
474 	if (!us->iobuf) {
475 		US_DEBUGP("I/O buffer allocation failed\n");
476 		return -ENOMEM;
477 	}
478 
479 	us->sensebuf = kmalloc(US_SENSE_SIZE, GFP_KERNEL);
480 	if (!us->sensebuf) {
481 		US_DEBUGP("Sense buffer allocation failed\n");
482 		return -ENOMEM;
483 	}
484 	return 0;
485 }
486 
487 /* Get the unusual_devs entries and the string descriptors */
488 static void get_device_info(struct us_data *us, int id_index)
489 {
490 	struct usb_device *dev = us->pusb_dev;
491 	struct usb_interface_descriptor *idesc =
492 		&us->pusb_intf->cur_altsetting->desc;
493 	struct us_unusual_dev *unusual_dev = &us_unusual_dev_list[id_index];
494 	struct usb_device_id *id = &storage_usb_ids[id_index];
495 
496 	/* Store the entries */
497 	us->unusual_dev = unusual_dev;
498 	us->subclass = (unusual_dev->useProtocol == US_SC_DEVICE) ?
499 			idesc->bInterfaceSubClass :
500 			unusual_dev->useProtocol;
501 	us->protocol = (unusual_dev->useTransport == US_PR_DEVICE) ?
502 			idesc->bInterfaceProtocol :
503 			unusual_dev->useTransport;
504 	us->flags = unusual_dev->flags;
505 
506 	/*
507 	 * This flag is only needed when we're in high-speed, so let's
508 	 * disable it if we're in full-speed
509 	 */
510 	if (dev->speed != USB_SPEED_HIGH)
511 		us->flags &= ~US_FL_GO_SLOW;
512 
513 	/* Log a message if a non-generic unusual_dev entry contains an
514 	 * unnecessary subclass or protocol override.  This may stimulate
515 	 * reports from users that will help us remove unneeded entries
516 	 * from the unusual_devs.h table.
517 	 */
518 	if (id->idVendor || id->idProduct) {
519 		static char *msgs[3] = {
520 			"an unneeded SubClass entry",
521 			"an unneeded Protocol entry",
522 			"unneeded SubClass and Protocol entries"};
523 		struct usb_device_descriptor *ddesc = &dev->descriptor;
524 		int msg = -1;
525 
526 		if (unusual_dev->useProtocol != US_SC_DEVICE &&
527 			us->subclass == idesc->bInterfaceSubClass)
528 			msg += 1;
529 		if (unusual_dev->useTransport != US_PR_DEVICE &&
530 			us->protocol == idesc->bInterfaceProtocol)
531 			msg += 2;
532 		if (msg >= 0 && !(unusual_dev->flags & US_FL_NEED_OVERRIDE))
533 			printk(KERN_NOTICE USB_STORAGE "This device "
534 				"(%04x,%04x,%04x S %02x P %02x)"
535 				" has %s in unusual_devs.h\n"
536 				"   Please send a copy of this message to "
537 				"<linux-usb-devel@lists.sourceforge.net>\n",
538 				le16_to_cpu(ddesc->idVendor),
539 				le16_to_cpu(ddesc->idProduct),
540 				le16_to_cpu(ddesc->bcdDevice),
541 				idesc->bInterfaceSubClass,
542 				idesc->bInterfaceProtocol,
543 				msgs[msg]);
544 	}
545 }
546 
547 /* Get the transport settings */
548 static int get_transport(struct us_data *us)
549 {
550 	switch (us->protocol) {
551 	case US_PR_CB:
552 		us->transport_name = "Control/Bulk";
553 		us->transport = usb_stor_CB_transport;
554 		us->transport_reset = usb_stor_CB_reset;
555 		us->max_lun = 7;
556 		break;
557 
558 	case US_PR_CBI:
559 		us->transport_name = "Control/Bulk/Interrupt";
560 		us->transport = usb_stor_CBI_transport;
561 		us->transport_reset = usb_stor_CB_reset;
562 		us->max_lun = 7;
563 		break;
564 
565 	case US_PR_BULK:
566 		us->transport_name = "Bulk";
567 		us->transport = usb_stor_Bulk_transport;
568 		us->transport_reset = usb_stor_Bulk_reset;
569 		break;
570 
571 #ifdef CONFIG_USB_STORAGE_USBAT
572 	case US_PR_USBAT:
573 		us->transport_name = "Shuttle USBAT";
574 		us->transport = usbat_transport;
575 		us->transport_reset = usb_stor_CB_reset;
576 		us->max_lun = 1;
577 		break;
578 #endif
579 
580 #ifdef CONFIG_USB_STORAGE_SDDR09
581 	case US_PR_EUSB_SDDR09:
582 		us->transport_name = "EUSB/SDDR09";
583 		us->transport = sddr09_transport;
584 		us->transport_reset = usb_stor_CB_reset;
585 		us->max_lun = 0;
586 		break;
587 #endif
588 
589 #ifdef CONFIG_USB_STORAGE_SDDR55
590 	case US_PR_SDDR55:
591 		us->transport_name = "SDDR55";
592 		us->transport = sddr55_transport;
593 		us->transport_reset = sddr55_reset;
594 		us->max_lun = 0;
595 		break;
596 #endif
597 
598 #ifdef CONFIG_USB_STORAGE_DPCM
599 	case US_PR_DPCM_USB:
600 		us->transport_name = "Control/Bulk-EUSB/SDDR09";
601 		us->transport = dpcm_transport;
602 		us->transport_reset = usb_stor_CB_reset;
603 		us->max_lun = 1;
604 		break;
605 #endif
606 
607 #ifdef CONFIG_USB_STORAGE_FREECOM
608 	case US_PR_FREECOM:
609 		us->transport_name = "Freecom";
610 		us->transport = freecom_transport;
611 		us->transport_reset = usb_stor_freecom_reset;
612 		us->max_lun = 0;
613 		break;
614 #endif
615 
616 #ifdef CONFIG_USB_STORAGE_DATAFAB
617 	case US_PR_DATAFAB:
618 		us->transport_name  = "Datafab Bulk-Only";
619 		us->transport = datafab_transport;
620 		us->transport_reset = usb_stor_Bulk_reset;
621 		us->max_lun = 1;
622 		break;
623 #endif
624 
625 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
626 	case US_PR_JUMPSHOT:
627 		us->transport_name  = "Lexar Jumpshot Control/Bulk";
628 		us->transport = jumpshot_transport;
629 		us->transport_reset = usb_stor_Bulk_reset;
630 		us->max_lun = 1;
631 		break;
632 #endif
633 
634 	default:
635 		return -EIO;
636 	}
637 	US_DEBUGP("Transport: %s\n", us->transport_name);
638 
639 	/* fix for single-lun devices */
640 	if (us->flags & US_FL_SINGLE_LUN)
641 		us->max_lun = 0;
642 	return 0;
643 }
644 
645 /* Get the protocol settings */
646 static int get_protocol(struct us_data *us)
647 {
648 	switch (us->subclass) {
649 	case US_SC_RBC:
650 		us->protocol_name = "Reduced Block Commands (RBC)";
651 		us->proto_handler = usb_stor_transparent_scsi_command;
652 		break;
653 
654 	case US_SC_8020:
655 		us->protocol_name = "8020i";
656 		us->proto_handler = usb_stor_ATAPI_command;
657 		us->max_lun = 0;
658 		break;
659 
660 	case US_SC_QIC:
661 		us->protocol_name = "QIC-157";
662 		us->proto_handler = usb_stor_qic157_command;
663 		us->max_lun = 0;
664 		break;
665 
666 	case US_SC_8070:
667 		us->protocol_name = "8070i";
668 		us->proto_handler = usb_stor_ATAPI_command;
669 		us->max_lun = 0;
670 		break;
671 
672 	case US_SC_SCSI:
673 		us->protocol_name = "Transparent SCSI";
674 		us->proto_handler = usb_stor_transparent_scsi_command;
675 		break;
676 
677 	case US_SC_UFI:
678 		us->protocol_name = "Uniform Floppy Interface (UFI)";
679 		us->proto_handler = usb_stor_ufi_command;
680 		break;
681 
682 #ifdef CONFIG_USB_STORAGE_ISD200
683 	case US_SC_ISD200:
684 		us->protocol_name = "ISD200 ATA/ATAPI";
685 		us->proto_handler = isd200_ata_command;
686 		break;
687 #endif
688 
689 	default:
690 		return -EIO;
691 	}
692 	US_DEBUGP("Protocol: %s\n", us->protocol_name);
693 	return 0;
694 }
695 
696 /* Get the pipe settings */
697 static int get_pipes(struct us_data *us)
698 {
699 	struct usb_host_interface *altsetting =
700 		us->pusb_intf->cur_altsetting;
701 	int i;
702 	struct usb_endpoint_descriptor *ep;
703 	struct usb_endpoint_descriptor *ep_in = NULL;
704 	struct usb_endpoint_descriptor *ep_out = NULL;
705 	struct usb_endpoint_descriptor *ep_int = NULL;
706 
707 	/*
708 	 * Find the endpoints we need.
709 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
710 	 * An optional interrupt is OK (necessary for CBI protocol).
711 	 * We will ignore any others.
712 	 */
713 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
714 		ep = &altsetting->endpoint[i].desc;
715 
716 		/* Is it a BULK endpoint? */
717 		if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
718 				== USB_ENDPOINT_XFER_BULK) {
719 			/* BULK in or out? */
720 			if (ep->bEndpointAddress & USB_DIR_IN)
721 				ep_in = ep;
722 			else
723 				ep_out = ep;
724 		}
725 
726 		/* Is it an interrupt endpoint? */
727 		else if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
728 				== USB_ENDPOINT_XFER_INT) {
729 			ep_int = ep;
730 		}
731 	}
732 
733 	if (!ep_in || !ep_out || (us->protocol == US_PR_CBI && !ep_int)) {
734 		US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
735 		return -EIO;
736 	}
737 
738 	/* Calculate and store the pipe values */
739 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
740 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
741 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
742 		ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
743 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
744 		ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
745 	if (ep_int) {
746 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
747 			ep_int->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
748 		us->ep_bInterval = ep_int->bInterval;
749 	}
750 	return 0;
751 }
752 
753 /* Initialize all the dynamic resources we need */
754 static int usb_stor_acquire_resources(struct us_data *us)
755 {
756 	int p;
757 	struct task_struct *th;
758 
759 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
760 	if (!us->current_urb) {
761 		US_DEBUGP("URB allocation failed\n");
762 		return -ENOMEM;
763 	}
764 
765 	/* Just before we start our control thread, initialize
766 	 * the device if it needs initialization */
767 	if (us->unusual_dev->initFunction) {
768 		p = us->unusual_dev->initFunction(us);
769 		if (p)
770 			return p;
771 	}
772 
773 	/* Start up our control thread */
774 	th = kthread_create(usb_stor_control_thread, us, "usb-storage");
775 	if (IS_ERR(th)) {
776 		printk(KERN_WARNING USB_STORAGE
777 		       "Unable to start control thread\n");
778 		return PTR_ERR(th);
779 	}
780 
781 	/* Take a reference to the host for the control thread and
782 	 * count it among all the threads we have launched.  Then
783 	 * start it up. */
784 	scsi_host_get(us_to_host(us));
785 	atomic_inc(&total_threads);
786 	wake_up_process(th);
787 
788 	return 0;
789 }
790 
791 /* Release all our dynamic resources */
792 static void usb_stor_release_resources(struct us_data *us)
793 {
794 	US_DEBUGP("-- %s\n", __FUNCTION__);
795 
796 	/* Tell the control thread to exit.  The SCSI host must
797 	 * already have been removed so it won't try to queue
798 	 * any more commands.
799 	 */
800 	US_DEBUGP("-- sending exit command to thread\n");
801 	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
802 	up(&us->sema);
803 
804 	/* Call the destructor routine, if it exists */
805 	if (us->extra_destructor) {
806 		US_DEBUGP("-- calling extra_destructor()\n");
807 		us->extra_destructor(us->extra);
808 	}
809 
810 	/* Free the extra data and the URB */
811 	kfree(us->extra);
812 	usb_free_urb(us->current_urb);
813 }
814 
815 /* Dissociate from the USB device */
816 static void dissociate_dev(struct us_data *us)
817 {
818 	US_DEBUGP("-- %s\n", __FUNCTION__);
819 
820 	kfree(us->sensebuf);
821 
822 	/* Free the device-related DMA-mapped buffers */
823 	if (us->cr)
824 		usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
825 				us->cr_dma);
826 	if (us->iobuf)
827 		usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
828 				us->iobuf_dma);
829 
830 	/* Remove our private data from the interface */
831 	usb_set_intfdata(us->pusb_intf, NULL);
832 }
833 
834 /* First stage of disconnect processing: stop all commands and remove
835  * the host */
836 static void quiesce_and_remove_host(struct us_data *us)
837 {
838 	/* Prevent new USB transfers, stop the current command, and
839 	 * interrupt a SCSI-scan or device-reset delay */
840 	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
841 	usb_stor_stop_transport(us);
842 	wake_up(&us->delay_wait);
843 
844 	/* It doesn't matter if the SCSI-scanning thread is still running.
845 	 * The thread will exit when it sees the DISCONNECTING flag. */
846 
847 	/* Wait for the current command to finish, then remove the host */
848 	down(&us->dev_semaphore);
849 	up(&us->dev_semaphore);
850 
851 	/* queuecommand won't accept any new commands and the control
852 	 * thread won't execute a previously-queued command.  If there
853 	 * is such a command pending, complete it with an error. */
854 	if (us->srb) {
855 		us->srb->result = DID_NO_CONNECT << 16;
856 		scsi_lock(us_to_host(us));
857 		us->srb->scsi_done(us->srb);
858 		us->srb = NULL;
859 		scsi_unlock(us_to_host(us));
860 	}
861 
862 	/* Now we own no commands so it's safe to remove the SCSI host */
863 	scsi_remove_host(us_to_host(us));
864 }
865 
866 /* Second stage of disconnect processing: deallocate all resources */
867 static void release_everything(struct us_data *us)
868 {
869 	usb_stor_release_resources(us);
870 	dissociate_dev(us);
871 
872 	/* Drop our reference to the host; the SCSI core will free it
873 	 * (and "us" along with it) when the refcount becomes 0. */
874 	scsi_host_put(us_to_host(us));
875 }
876 
877 /* Thread to carry out delayed SCSI-device scanning */
878 static int usb_stor_scan_thread(void * __us)
879 {
880 	struct us_data *us = (struct us_data *)__us;
881 
882 	printk(KERN_DEBUG
883 		"usb-storage: device found at %d\n", us->pusb_dev->devnum);
884 
885 	/* Wait for the timeout to expire or for a disconnect */
886 	if (delay_use > 0) {
887 		printk(KERN_DEBUG "usb-storage: waiting for device "
888 				"to settle before scanning\n");
889 retry:
890 		wait_event_interruptible_timeout(us->delay_wait,
891 				test_bit(US_FLIDX_DISCONNECTING, &us->flags),
892 				delay_use * HZ);
893 		if (try_to_freeze())
894 			goto retry;
895 	}
896 
897 	/* If the device is still connected, perform the scanning */
898 	if (!test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
899 
900 		/* For bulk-only devices, determine the max LUN value */
901 		if (us->protocol == US_PR_BULK &&
902 				!(us->flags & US_FL_SINGLE_LUN)) {
903 			down(&us->dev_semaphore);
904 			us->max_lun = usb_stor_Bulk_max_lun(us);
905 			up(&us->dev_semaphore);
906 		}
907 		scsi_scan_host(us_to_host(us));
908 		printk(KERN_DEBUG "usb-storage: device scan complete\n");
909 
910 		/* Should we unbind if no devices were detected? */
911 	}
912 
913 	scsi_host_put(us_to_host(us));
914 	complete_and_exit(&threads_gone, 0);
915 }
916 
917 
918 /* Probe to see if we can drive a newly-connected USB device */
919 static int storage_probe(struct usb_interface *intf,
920 			 const struct usb_device_id *id)
921 {
922 	struct Scsi_Host *host;
923 	struct us_data *us;
924 	const int id_index = id - storage_usb_ids;
925 	int result;
926 	struct task_struct *th;
927 
928 	US_DEBUGP("USB Mass Storage device detected\n");
929 
930 	/*
931 	 * Ask the SCSI layer to allocate a host structure, with extra
932 	 * space at the end for our private us_data structure.
933 	 */
934 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
935 	if (!host) {
936 		printk(KERN_WARNING USB_STORAGE
937 			"Unable to allocate the scsi host\n");
938 		return -ENOMEM;
939 	}
940 
941 	us = host_to_us(host);
942 	memset(us, 0, sizeof(struct us_data));
943 	init_MUTEX(&(us->dev_semaphore));
944 	init_MUTEX_LOCKED(&(us->sema));
945 	init_completion(&(us->notify));
946 	init_waitqueue_head(&us->delay_wait);
947 
948 	/* Associate the us_data structure with the USB device */
949 	result = associate_dev(us, intf);
950 	if (result)
951 		goto BadDevice;
952 
953 	/*
954 	 * Get the unusual_devs entries and the descriptors
955 	 *
956 	 * id_index is calculated in the declaration to be the index number
957 	 * of the match from the usb_device_id table, so we can find the
958 	 * corresponding entry in the private table.
959 	 */
960 	get_device_info(us, id_index);
961 
962 #ifdef CONFIG_USB_STORAGE_SDDR09
963 	if (us->protocol == US_PR_EUSB_SDDR09 ||
964 			us->protocol == US_PR_DPCM_USB) {
965 		/* set the configuration -- STALL is an acceptable response here */
966 		if (us->pusb_dev->actconfig->desc.bConfigurationValue != 1) {
967 			US_DEBUGP("active config #%d != 1 ??\n", us->pusb_dev
968 				->actconfig->desc.bConfigurationValue);
969 			goto BadDevice;
970 		}
971 		result = usb_reset_configuration(us->pusb_dev);
972 
973 		US_DEBUGP("Result of usb_reset_configuration is %d\n", result);
974 		if (result == -EPIPE) {
975 			US_DEBUGP("-- stall on control interface\n");
976 		} else if (result != 0) {
977 			/* it's not a stall, but another error -- time to bail */
978 			US_DEBUGP("-- Unknown error.  Rejecting device\n");
979 			goto BadDevice;
980 		}
981 	}
982 #endif
983 
984 	/* Get the transport, protocol, and pipe settings */
985 	result = get_transport(us);
986 	if (result)
987 		goto BadDevice;
988 	result = get_protocol(us);
989 	if (result)
990 		goto BadDevice;
991 	result = get_pipes(us);
992 	if (result)
993 		goto BadDevice;
994 
995 	/* Acquire all the other resources and add the host */
996 	result = usb_stor_acquire_resources(us);
997 	if (result)
998 		goto BadDevice;
999 	result = scsi_add_host(host, &intf->dev);
1000 	if (result) {
1001 		printk(KERN_WARNING USB_STORAGE
1002 			"Unable to add the scsi host\n");
1003 		goto BadDevice;
1004 	}
1005 
1006 	/* Start up the thread for delayed SCSI-device scanning */
1007 	th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
1008 	if (IS_ERR(th)) {
1009 		printk(KERN_WARNING USB_STORAGE
1010 		       "Unable to start the device-scanning thread\n");
1011 		quiesce_and_remove_host(us);
1012 		result = PTR_ERR(th);
1013 		goto BadDevice;
1014 	}
1015 
1016 	/* Take a reference to the host for the scanning thread and
1017 	 * count it among all the threads we have launched.  Then
1018 	 * start it up. */
1019 	scsi_host_get(us_to_host(us));
1020 	atomic_inc(&total_threads);
1021 	wake_up_process(th);
1022 
1023 	return 0;
1024 
1025 	/* We come here if there are any problems */
1026 BadDevice:
1027 	US_DEBUGP("storage_probe() failed\n");
1028 	release_everything(us);
1029 	return result;
1030 }
1031 
1032 /* Handle a disconnect event from the USB core */
1033 static void storage_disconnect(struct usb_interface *intf)
1034 {
1035 	struct us_data *us = usb_get_intfdata(intf);
1036 
1037 	US_DEBUGP("storage_disconnect() called\n");
1038 	quiesce_and_remove_host(us);
1039 	release_everything(us);
1040 }
1041 
1042 /***********************************************************************
1043  * Initialization and registration
1044  ***********************************************************************/
1045 
1046 static struct usb_driver usb_storage_driver = {
1047 	.owner =	THIS_MODULE,
1048 	.name =		"usb-storage",
1049 	.probe =	storage_probe,
1050 	.disconnect =	storage_disconnect,
1051 #ifdef CONFIG_PM
1052 	.suspend =	storage_suspend,
1053 	.resume =	storage_resume,
1054 #endif
1055 	.id_table =	storage_usb_ids,
1056 };
1057 
1058 static int __init usb_stor_init(void)
1059 {
1060 	int retval;
1061 	printk(KERN_INFO "Initializing USB Mass Storage driver...\n");
1062 
1063 	/* register the driver, return usb_register return code if error */
1064 	retval = usb_register(&usb_storage_driver);
1065 	if (retval == 0)
1066 		printk(KERN_INFO "USB Mass Storage support registered.\n");
1067 
1068 	return retval;
1069 }
1070 
1071 static void __exit usb_stor_exit(void)
1072 {
1073 	US_DEBUGP("usb_stor_exit() called\n");
1074 
1075 	/* Deregister the driver
1076 	 * This will cause disconnect() to be called for each
1077 	 * attached unit
1078 	 */
1079 	US_DEBUGP("-- calling usb_deregister()\n");
1080 	usb_deregister(&usb_storage_driver) ;
1081 
1082 	/* Don't return until all of our control and scanning threads
1083 	 * have exited.  Since each thread signals threads_gone as its
1084 	 * last act, we have to call wait_for_completion the right number
1085 	 * of times.
1086 	 */
1087 	while (atomic_read(&total_threads) > 0) {
1088 		wait_for_completion(&threads_gone);
1089 		atomic_dec(&total_threads);
1090 	}
1091 }
1092 
1093 module_init(usb_stor_init);
1094 module_exit(usb_stor_exit);
1095