xref: /linux/drivers/usb/storage/usb.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
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/sched.h>
51 #include <linux/errno.h>
52 #include <linux/suspend.h>
53 #include <linux/module.h>
54 #include <linux/init.h>
55 #include <linux/slab.h>
56 #include <linux/kthread.h>
57 #include <linux/mutex.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 #ifdef CONFIG_USB_STORAGE_ALAUDA
98 #include "alauda.h"
99 #endif
100 
101 /* Some informational data */
102 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
103 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
104 MODULE_LICENSE("GPL");
105 
106 static unsigned int delay_use = 5;
107 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
108 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
109 
110 
111 /* These are used to make sure the module doesn't unload before all the
112  * threads have exited.
113  */
114 static atomic_t total_threads = ATOMIC_INIT(0);
115 static DECLARE_COMPLETION(threads_gone);
116 
117 
118 /*
119  * The entries in this table correspond, line for line,
120  * with the entries of us_unusual_dev_list[].
121  */
122 #ifndef CONFIG_USB_LIBUSUAL
123 
124 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
125 		    vendorName, productName,useProtocol, useTransport, \
126 		    initFunction, flags) \
127 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin,bcdDeviceMax), \
128   .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }
129 
130 #define USUAL_DEV(useProto, useTrans, useType) \
131 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, useProto, useTrans), \
132   .driver_info = (USB_US_TYPE_STOR<<24) }
133 
134 static struct usb_device_id storage_usb_ids [] = {
135 
136 #	include "unusual_devs.h"
137 #undef UNUSUAL_DEV
138 #undef USUAL_DEV
139 	/* Terminating entry */
140 	{ }
141 };
142 
143 MODULE_DEVICE_TABLE (usb, storage_usb_ids);
144 #endif /* CONFIG_USB_LIBUSUAL */
145 
146 /* This is the list of devices we recognize, along with their flag data */
147 
148 /* The vendor name should be kept at eight characters or less, and
149  * the product name should be kept at 16 characters or less. If a device
150  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
151  * normally generated by a device thorugh the INQUIRY response will be
152  * taken from this list, and this is the reason for the above size
153  * restriction. However, if the flag is not present, then you
154  * are free to use as many characters as you like.
155  */
156 
157 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
158 		    vendor_name, product_name, use_protocol, use_transport, \
159 		    init_function, Flags) \
160 { \
161 	.vendorName = vendor_name,	\
162 	.productName = product_name,	\
163 	.useProtocol = use_protocol,	\
164 	.useTransport = use_transport,	\
165 	.initFunction = init_function,	\
166 }
167 
168 #define USUAL_DEV(use_protocol, use_transport, use_type) \
169 { \
170 	.useProtocol = use_protocol,	\
171 	.useTransport = use_transport,	\
172 }
173 
174 static struct us_unusual_dev us_unusual_dev_list[] = {
175 #	include "unusual_devs.h"
176 #	undef UNUSUAL_DEV
177 #	undef USUAL_DEV
178 
179 	/* Terminating entry */
180 	{ NULL }
181 };
182 
183 
184 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
185 
186 static int storage_suspend(struct usb_interface *iface, pm_message_t message)
187 {
188 	struct us_data *us = usb_get_intfdata(iface);
189 
190 	/* Wait until no command is running */
191 	mutex_lock(&us->dev_mutex);
192 
193 	US_DEBUGP("%s\n", __FUNCTION__);
194 	if (us->suspend_resume_hook)
195 		(us->suspend_resume_hook)(us, US_SUSPEND);
196 	iface->dev.power.power_state.event = message.event;
197 
198 	/* When runtime PM is working, we'll set a flag to indicate
199 	 * whether we should autoresume when a SCSI request arrives. */
200 
201 	mutex_unlock(&us->dev_mutex);
202 	return 0;
203 }
204 
205 static int storage_resume(struct usb_interface *iface)
206 {
207 	struct us_data *us = usb_get_intfdata(iface);
208 
209 	mutex_lock(&us->dev_mutex);
210 
211 	US_DEBUGP("%s\n", __FUNCTION__);
212 	if (us->suspend_resume_hook)
213 		(us->suspend_resume_hook)(us, US_RESUME);
214 	iface->dev.power.power_state.event = PM_EVENT_ON;
215 
216 	mutex_unlock(&us->dev_mutex);
217 	return 0;
218 }
219 
220 #endif /* CONFIG_PM */
221 
222 /*
223  * The next two routines get called just before and just after
224  * a USB port reset, whether from this driver or a different one.
225  */
226 
227 static void storage_pre_reset(struct usb_interface *iface)
228 {
229 	struct us_data *us = usb_get_intfdata(iface);
230 
231 	US_DEBUGP("%s\n", __FUNCTION__);
232 
233 	/* Make sure no command runs during the reset */
234 	mutex_lock(&us->dev_mutex);
235 }
236 
237 static void storage_post_reset(struct usb_interface *iface)
238 {
239 	struct us_data *us = usb_get_intfdata(iface);
240 
241 	US_DEBUGP("%s\n", __FUNCTION__);
242 
243 	/* Report the reset to the SCSI core */
244 	scsi_lock(us_to_host(us));
245 	usb_stor_report_bus_reset(us);
246 	scsi_unlock(us_to_host(us));
247 
248 	/* FIXME: Notify the subdrivers that they need to reinitialize
249 	 * the device */
250 	mutex_unlock(&us->dev_mutex);
251 }
252 
253 /*
254  * fill_inquiry_response takes an unsigned char array (which must
255  * be at least 36 characters) and populates the vendor name,
256  * product name, and revision fields. Then the array is copied
257  * into the SCSI command's response buffer (oddly enough
258  * called request_buffer). data_len contains the length of the
259  * data array, which again must be at least 36.
260  */
261 
262 void fill_inquiry_response(struct us_data *us, unsigned char *data,
263 		unsigned int data_len)
264 {
265 	if (data_len<36) // You lose.
266 		return;
267 
268 	if(data[0]&0x20) { /* USB device currently not connected. Return
269 			      peripheral qualifier 001b ("...however, the
270 			      physical device is not currently connected
271 			      to this logical unit") and leave vendor and
272 			      product identification empty. ("If the target
273 			      does store some of the INQUIRY data on the
274 			      device, it may return zeros or ASCII spaces
275 			      (20h) in those fields until the data is
276 			      available from the device."). */
277 		memset(data+8,0,28);
278 	} else {
279 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
280 		memcpy(data+8, us->unusual_dev->vendorName,
281 			strlen(us->unusual_dev->vendorName) > 8 ? 8 :
282 			strlen(us->unusual_dev->vendorName));
283 		memcpy(data+16, us->unusual_dev->productName,
284 			strlen(us->unusual_dev->productName) > 16 ? 16 :
285 			strlen(us->unusual_dev->productName));
286 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
287 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
288 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
289 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
290 	}
291 
292 	usb_stor_set_xfer_buf(data, data_len, us->srb);
293 }
294 
295 static int usb_stor_control_thread(void * __us)
296 {
297 	struct us_data *us = (struct us_data *)__us;
298 	struct Scsi_Host *host = us_to_host(us);
299 
300 	current->flags |= PF_NOFREEZE;
301 
302 	for(;;) {
303 		US_DEBUGP("*** thread sleeping.\n");
304 		if(down_interruptible(&us->sema))
305 			break;
306 
307 		US_DEBUGP("*** thread awakened.\n");
308 
309 		/* lock the device pointers */
310 		mutex_lock(&(us->dev_mutex));
311 
312 		/* if the device has disconnected, we are free to exit */
313 		if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
314 			US_DEBUGP("-- exiting\n");
315 			mutex_unlock(&us->dev_mutex);
316 			break;
317 		}
318 
319 		/* lock access to the state */
320 		scsi_lock(host);
321 
322 		/* has the command timed out *already* ? */
323 		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
324 			us->srb->result = DID_ABORT << 16;
325 			goto SkipForAbort;
326 		}
327 
328 		scsi_unlock(host);
329 
330 		/* reject the command if the direction indicator
331 		 * is UNKNOWN
332 		 */
333 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
334 			US_DEBUGP("UNKNOWN data direction\n");
335 			us->srb->result = DID_ERROR << 16;
336 		}
337 
338 		/* reject if target != 0 or if LUN is higher than
339 		 * the maximum known LUN
340 		 */
341 		else if (us->srb->device->id &&
342 				!(us->flags & US_FL_SCM_MULT_TARG)) {
343 			US_DEBUGP("Bad target number (%d:%d)\n",
344 				  us->srb->device->id, us->srb->device->lun);
345 			us->srb->result = DID_BAD_TARGET << 16;
346 		}
347 
348 		else if (us->srb->device->lun > us->max_lun) {
349 			US_DEBUGP("Bad LUN (%d:%d)\n",
350 				  us->srb->device->id, us->srb->device->lun);
351 			us->srb->result = DID_BAD_TARGET << 16;
352 		}
353 
354 		/* Handle those devices which need us to fake
355 		 * their inquiry data */
356 		else if ((us->srb->cmnd[0] == INQUIRY) &&
357 			    (us->flags & US_FL_FIX_INQUIRY)) {
358 			unsigned char data_ptr[36] = {
359 			    0x00, 0x80, 0x02, 0x02,
360 			    0x1F, 0x00, 0x00, 0x00};
361 
362 			US_DEBUGP("Faking INQUIRY command\n");
363 			fill_inquiry_response(us, data_ptr, 36);
364 			us->srb->result = SAM_STAT_GOOD;
365 		}
366 
367 		/* we've got a command, let's do it! */
368 		else {
369 			US_DEBUG(usb_stor_show_command(us->srb));
370 			us->proto_handler(us->srb, us);
371 		}
372 
373 		/* lock access to the state */
374 		scsi_lock(host);
375 
376 		/* indicate that the command is done */
377 		if (us->srb->result != DID_ABORT << 16) {
378 			US_DEBUGP("scsi cmd done, result=0x%x\n",
379 				   us->srb->result);
380 			us->srb->scsi_done(us->srb);
381 		} else {
382 SkipForAbort:
383 			US_DEBUGP("scsi command aborted\n");
384 		}
385 
386 		/* If an abort request was received we need to signal that
387 		 * the abort has finished.  The proper test for this is
388 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
389 		 * the timeout might have occurred after the command had
390 		 * already completed with a different result code. */
391 		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
392 			complete(&(us->notify));
393 
394 			/* Allow USB transfers to resume */
395 			clear_bit(US_FLIDX_ABORTING, &us->flags);
396 			clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
397 		}
398 
399 		/* finished working on this command */
400 		us->srb = NULL;
401 		scsi_unlock(host);
402 
403 		/* unlock the device pointers */
404 		mutex_unlock(&us->dev_mutex);
405 	} /* for (;;) */
406 
407 	scsi_host_put(host);
408 
409 	/* notify the exit routine that we're actually exiting now
410 	 *
411 	 * complete()/wait_for_completion() is similar to up()/down(),
412 	 * except that complete() is safe in the case where the structure
413 	 * is getting deleted in a parallel mode of execution (i.e. just
414 	 * after the down() -- that's necessary for the thread-shutdown
415 	 * case.
416 	 *
417 	 * complete_and_exit() goes even further than this -- it is safe in
418 	 * the case that the thread of the caller is going away (not just
419 	 * the structure) -- this is necessary for the module-remove case.
420 	 * This is important in preemption kernels, which transfer the flow
421 	 * of execution immediately upon a complete().
422 	 */
423 	complete_and_exit(&threads_gone, 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 	US_DEBUGP("-- %s\n", __FUNCTION__);
434 
435 	/* Fill in the device-related fields */
436 	us->pusb_dev = interface_to_usbdev(intf);
437 	us->pusb_intf = intf;
438 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
439 	US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
440 			le16_to_cpu(us->pusb_dev->descriptor.idVendor),
441 			le16_to_cpu(us->pusb_dev->descriptor.idProduct),
442 			le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
443 	US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
444 			intf->cur_altsetting->desc.bInterfaceSubClass,
445 			intf->cur_altsetting->desc.bInterfaceProtocol);
446 
447 	/* Store our private data in the interface */
448 	usb_set_intfdata(intf, us);
449 
450 	/* Allocate the device-related DMA-mapped buffers */
451 	us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
452 			GFP_KERNEL, &us->cr_dma);
453 	if (!us->cr) {
454 		US_DEBUGP("usb_ctrlrequest allocation failed\n");
455 		return -ENOMEM;
456 	}
457 
458 	us->iobuf = usb_buffer_alloc(us->pusb_dev, US_IOBUF_SIZE,
459 			GFP_KERNEL, &us->iobuf_dma);
460 	if (!us->iobuf) {
461 		US_DEBUGP("I/O buffer allocation failed\n");
462 		return -ENOMEM;
463 	}
464 
465 	us->sensebuf = kmalloc(US_SENSE_SIZE, GFP_KERNEL);
466 	if (!us->sensebuf) {
467 		US_DEBUGP("Sense buffer allocation failed\n");
468 		return -ENOMEM;
469 	}
470 	return 0;
471 }
472 
473 /* Find an unusual_dev descriptor (always succeeds in the current code) */
474 static struct us_unusual_dev *find_unusual(const struct usb_device_id *id)
475 {
476 	const int id_index = id - storage_usb_ids;
477 	return &us_unusual_dev_list[id_index];
478 }
479 
480 /* Get the unusual_devs entries and the string descriptors */
481 static void get_device_info(struct us_data *us, const struct usb_device_id *id)
482 {
483 	struct usb_device *dev = us->pusb_dev;
484 	struct usb_interface_descriptor *idesc =
485 		&us->pusb_intf->cur_altsetting->desc;
486 	struct us_unusual_dev *unusual_dev = find_unusual(id);
487 
488 	/* Store the entries */
489 	us->unusual_dev = unusual_dev;
490 	us->subclass = (unusual_dev->useProtocol == US_SC_DEVICE) ?
491 			idesc->bInterfaceSubClass :
492 			unusual_dev->useProtocol;
493 	us->protocol = (unusual_dev->useTransport == US_PR_DEVICE) ?
494 			idesc->bInterfaceProtocol :
495 			unusual_dev->useTransport;
496 	us->flags = USB_US_ORIG_FLAGS(id->driver_info);
497 
498 	/*
499 	 * This flag is only needed when we're in high-speed, so let's
500 	 * disable it if we're in full-speed
501 	 */
502 	if (dev->speed != USB_SPEED_HIGH)
503 		us->flags &= ~US_FL_GO_SLOW;
504 
505 	/* Log a message if a non-generic unusual_dev entry contains an
506 	 * unnecessary subclass or protocol override.  This may stimulate
507 	 * reports from users that will help us remove unneeded entries
508 	 * from the unusual_devs.h table.
509 	 */
510 	if (id->idVendor || id->idProduct) {
511 		static const char *msgs[3] = {
512 			"an unneeded SubClass entry",
513 			"an unneeded Protocol entry",
514 			"unneeded SubClass and Protocol entries"};
515 		struct usb_device_descriptor *ddesc = &dev->descriptor;
516 		int msg = -1;
517 
518 		if (unusual_dev->useProtocol != US_SC_DEVICE &&
519 			us->subclass == idesc->bInterfaceSubClass)
520 			msg += 1;
521 		if (unusual_dev->useTransport != US_PR_DEVICE &&
522 			us->protocol == idesc->bInterfaceProtocol)
523 			msg += 2;
524 		if (msg >= 0 && !(us->flags & US_FL_NEED_OVERRIDE))
525 			printk(KERN_NOTICE USB_STORAGE "This device "
526 				"(%04x,%04x,%04x S %02x P %02x)"
527 				" has %s in unusual_devs.h\n"
528 				"   Please send a copy of this message to "
529 				"<linux-usb-devel@lists.sourceforge.net>\n",
530 				le16_to_cpu(ddesc->idVendor),
531 				le16_to_cpu(ddesc->idProduct),
532 				le16_to_cpu(ddesc->bcdDevice),
533 				idesc->bInterfaceSubClass,
534 				idesc->bInterfaceProtocol,
535 				msgs[msg]);
536 	}
537 }
538 
539 /* Get the transport settings */
540 static int get_transport(struct us_data *us)
541 {
542 	switch (us->protocol) {
543 	case US_PR_CB:
544 		us->transport_name = "Control/Bulk";
545 		us->transport = usb_stor_CB_transport;
546 		us->transport_reset = usb_stor_CB_reset;
547 		us->max_lun = 7;
548 		break;
549 
550 	case US_PR_CBI:
551 		us->transport_name = "Control/Bulk/Interrupt";
552 		us->transport = usb_stor_CBI_transport;
553 		us->transport_reset = usb_stor_CB_reset;
554 		us->max_lun = 7;
555 		break;
556 
557 	case US_PR_BULK:
558 		us->transport_name = "Bulk";
559 		us->transport = usb_stor_Bulk_transport;
560 		us->transport_reset = usb_stor_Bulk_reset;
561 		break;
562 
563 #ifdef CONFIG_USB_STORAGE_USBAT
564 	case US_PR_USBAT:
565 		us->transport_name = "Shuttle USBAT";
566 		us->transport = usbat_transport;
567 		us->transport_reset = usb_stor_CB_reset;
568 		us->max_lun = 1;
569 		break;
570 #endif
571 
572 #ifdef CONFIG_USB_STORAGE_SDDR09
573 	case US_PR_EUSB_SDDR09:
574 		us->transport_name = "EUSB/SDDR09";
575 		us->transport = sddr09_transport;
576 		us->transport_reset = usb_stor_CB_reset;
577 		us->max_lun = 0;
578 		break;
579 #endif
580 
581 #ifdef CONFIG_USB_STORAGE_SDDR55
582 	case US_PR_SDDR55:
583 		us->transport_name = "SDDR55";
584 		us->transport = sddr55_transport;
585 		us->transport_reset = sddr55_reset;
586 		us->max_lun = 0;
587 		break;
588 #endif
589 
590 #ifdef CONFIG_USB_STORAGE_DPCM
591 	case US_PR_DPCM_USB:
592 		us->transport_name = "Control/Bulk-EUSB/SDDR09";
593 		us->transport = dpcm_transport;
594 		us->transport_reset = usb_stor_CB_reset;
595 		us->max_lun = 1;
596 		break;
597 #endif
598 
599 #ifdef CONFIG_USB_STORAGE_FREECOM
600 	case US_PR_FREECOM:
601 		us->transport_name = "Freecom";
602 		us->transport = freecom_transport;
603 		us->transport_reset = usb_stor_freecom_reset;
604 		us->max_lun = 0;
605 		break;
606 #endif
607 
608 #ifdef CONFIG_USB_STORAGE_DATAFAB
609 	case US_PR_DATAFAB:
610 		us->transport_name  = "Datafab Bulk-Only";
611 		us->transport = datafab_transport;
612 		us->transport_reset = usb_stor_Bulk_reset;
613 		us->max_lun = 1;
614 		break;
615 #endif
616 
617 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
618 	case US_PR_JUMPSHOT:
619 		us->transport_name  = "Lexar Jumpshot Control/Bulk";
620 		us->transport = jumpshot_transport;
621 		us->transport_reset = usb_stor_Bulk_reset;
622 		us->max_lun = 1;
623 		break;
624 #endif
625 
626 #ifdef CONFIG_USB_STORAGE_ALAUDA
627 	case US_PR_ALAUDA:
628 		us->transport_name  = "Alauda Control/Bulk";
629 		us->transport = alauda_transport;
630 		us->transport_reset = usb_stor_Bulk_reset;
631 		us->max_lun = 1;
632 		break;
633 #endif
634 
635 	default:
636 		return -EIO;
637 	}
638 	US_DEBUGP("Transport: %s\n", us->transport_name);
639 
640 	/* fix for single-lun devices */
641 	if (us->flags & US_FL_SINGLE_LUN)
642 		us->max_lun = 0;
643 	return 0;
644 }
645 
646 /* Get the protocol settings */
647 static int get_protocol(struct us_data *us)
648 {
649 	switch (us->subclass) {
650 	case US_SC_RBC:
651 		us->protocol_name = "Reduced Block Commands (RBC)";
652 		us->proto_handler = usb_stor_transparent_scsi_command;
653 		break;
654 
655 	case US_SC_8020:
656 		us->protocol_name = "8020i";
657 		us->proto_handler = usb_stor_ATAPI_command;
658 		us->max_lun = 0;
659 		break;
660 
661 	case US_SC_QIC:
662 		us->protocol_name = "QIC-157";
663 		us->proto_handler = usb_stor_qic157_command;
664 		us->max_lun = 0;
665 		break;
666 
667 	case US_SC_8070:
668 		us->protocol_name = "8070i";
669 		us->proto_handler = usb_stor_ATAPI_command;
670 		us->max_lun = 0;
671 		break;
672 
673 	case US_SC_SCSI:
674 		us->protocol_name = "Transparent SCSI";
675 		us->proto_handler = usb_stor_transparent_scsi_command;
676 		break;
677 
678 	case US_SC_UFI:
679 		us->protocol_name = "Uniform Floppy Interface (UFI)";
680 		us->proto_handler = usb_stor_ufi_command;
681 		break;
682 
683 #ifdef CONFIG_USB_STORAGE_ISD200
684 	case US_SC_ISD200:
685 		us->protocol_name = "ISD200 ATA/ATAPI";
686 		us->proto_handler = isd200_ata_command;
687 		break;
688 #endif
689 
690 	default:
691 		return -EIO;
692 	}
693 	US_DEBUGP("Protocol: %s\n", us->protocol_name);
694 	return 0;
695 }
696 
697 /* Get the pipe settings */
698 static int get_pipes(struct us_data *us)
699 {
700 	struct usb_host_interface *altsetting =
701 		us->pusb_intf->cur_altsetting;
702 	int i;
703 	struct usb_endpoint_descriptor *ep;
704 	struct usb_endpoint_descriptor *ep_in = NULL;
705 	struct usb_endpoint_descriptor *ep_out = NULL;
706 	struct usb_endpoint_descriptor *ep_int = NULL;
707 
708 	/*
709 	 * Find the endpoints we need.
710 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
711 	 * An optional interrupt is OK (necessary for CBI protocol).
712 	 * We will ignore any others.
713 	 */
714 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
715 		ep = &altsetting->endpoint[i].desc;
716 
717 		/* Is it a BULK endpoint? */
718 		if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
719 				== USB_ENDPOINT_XFER_BULK) {
720 			/* BULK in or out? */
721 			if (ep->bEndpointAddress & USB_DIR_IN)
722 				ep_in = ep;
723 			else
724 				ep_out = ep;
725 		}
726 
727 		/* Is it an interrupt endpoint? */
728 		else if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
729 				== USB_ENDPOINT_XFER_INT) {
730 			ep_int = ep;
731 		}
732 	}
733 
734 	if (!ep_in || !ep_out || (us->protocol == US_PR_CBI && !ep_int)) {
735 		US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
736 		return -EIO;
737 	}
738 
739 	/* Calculate and store the pipe values */
740 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
741 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
742 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
743 		ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
744 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
745 		ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
746 	if (ep_int) {
747 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
748 			ep_int->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
749 		us->ep_bInterval = ep_int->bInterval;
750 	}
751 	return 0;
752 }
753 
754 /* Initialize all the dynamic resources we need */
755 static int usb_stor_acquire_resources(struct us_data *us)
756 {
757 	int p;
758 	struct task_struct *th;
759 
760 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
761 	if (!us->current_urb) {
762 		US_DEBUGP("URB allocation failed\n");
763 		return -ENOMEM;
764 	}
765 
766 	/* Just before we start our control thread, initialize
767 	 * the device if it needs initialization */
768 	if (us->unusual_dev->initFunction) {
769 		p = us->unusual_dev->initFunction(us);
770 		if (p)
771 			return p;
772 	}
773 
774 	/* Start up our control thread */
775 	th = kthread_create(usb_stor_control_thread, us, "usb-storage");
776 	if (IS_ERR(th)) {
777 		printk(KERN_WARNING USB_STORAGE
778 		       "Unable to start control thread\n");
779 		return PTR_ERR(th);
780 	}
781 
782 	/* Take a reference to the host for the control thread and
783 	 * count it among all the threads we have launched.  Then
784 	 * start it up. */
785 	scsi_host_get(us_to_host(us));
786 	atomic_inc(&total_threads);
787 	wake_up_process(th);
788 
789 	return 0;
790 }
791 
792 /* Release all our dynamic resources */
793 static void usb_stor_release_resources(struct us_data *us)
794 {
795 	US_DEBUGP("-- %s\n", __FUNCTION__);
796 
797 	/* Tell the control thread to exit.  The SCSI host must
798 	 * already have been removed so it won't try to queue
799 	 * any more commands.
800 	 */
801 	US_DEBUGP("-- sending exit command to thread\n");
802 	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
803 	up(&us->sema);
804 
805 	/* Call the destructor routine, if it exists */
806 	if (us->extra_destructor) {
807 		US_DEBUGP("-- calling extra_destructor()\n");
808 		us->extra_destructor(us->extra);
809 	}
810 
811 	/* Free the extra data and the URB */
812 	kfree(us->extra);
813 	usb_free_urb(us->current_urb);
814 }
815 
816 /* Dissociate from the USB device */
817 static void dissociate_dev(struct us_data *us)
818 {
819 	US_DEBUGP("-- %s\n", __FUNCTION__);
820 
821 	kfree(us->sensebuf);
822 
823 	/* Free the device-related DMA-mapped buffers */
824 	if (us->cr)
825 		usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
826 				us->cr_dma);
827 	if (us->iobuf)
828 		usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
829 				us->iobuf_dma);
830 
831 	/* Remove our private data from the interface */
832 	usb_set_intfdata(us->pusb_intf, NULL);
833 }
834 
835 /* First stage of disconnect processing: stop all commands and remove
836  * the host */
837 static void quiesce_and_remove_host(struct us_data *us)
838 {
839 	/* Prevent new USB transfers, stop the current command, and
840 	 * interrupt a SCSI-scan or device-reset delay */
841 	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
842 	usb_stor_stop_transport(us);
843 	wake_up(&us->delay_wait);
844 
845 	/* It doesn't matter if the SCSI-scanning thread is still running.
846 	 * The thread will exit when it sees the DISCONNECTING flag. */
847 
848 	/* Wait for the current command to finish, then remove the host */
849 	mutex_lock(&us->dev_mutex);
850 	mutex_unlock(&us->dev_mutex);
851 
852 	/* queuecommand won't accept any new commands and the control
853 	 * thread won't execute a previously-queued command.  If there
854 	 * is such a command pending, complete it with an error. */
855 	if (us->srb) {
856 		us->srb->result = DID_NO_CONNECT << 16;
857 		scsi_lock(us_to_host(us));
858 		us->srb->scsi_done(us->srb);
859 		us->srb = NULL;
860 		scsi_unlock(us_to_host(us));
861 	}
862 
863 	/* Now we own no commands so it's safe to remove the SCSI host */
864 	scsi_remove_host(us_to_host(us));
865 }
866 
867 /* Second stage of disconnect processing: deallocate all resources */
868 static void release_everything(struct us_data *us)
869 {
870 	usb_stor_release_resources(us);
871 	dissociate_dev(us);
872 
873 	/* Drop our reference to the host; the SCSI core will free it
874 	 * (and "us" along with it) when the refcount becomes 0. */
875 	scsi_host_put(us_to_host(us));
876 }
877 
878 /* Thread to carry out delayed SCSI-device scanning */
879 static int usb_stor_scan_thread(void * __us)
880 {
881 	struct us_data *us = (struct us_data *)__us;
882 
883 	printk(KERN_DEBUG
884 		"usb-storage: device found at %d\n", us->pusb_dev->devnum);
885 
886 	/* Wait for the timeout to expire or for a disconnect */
887 	if (delay_use > 0) {
888 		printk(KERN_DEBUG "usb-storage: waiting for device "
889 				"to settle before scanning\n");
890 retry:
891 		wait_event_interruptible_timeout(us->delay_wait,
892 				test_bit(US_FLIDX_DISCONNECTING, &us->flags),
893 				delay_use * HZ);
894 		if (try_to_freeze())
895 			goto retry;
896 	}
897 
898 	/* If the device is still connected, perform the scanning */
899 	if (!test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
900 
901 		/* For bulk-only devices, determine the max LUN value */
902 		if (us->protocol == US_PR_BULK &&
903 				!(us->flags & US_FL_SINGLE_LUN)) {
904 			mutex_lock(&us->dev_mutex);
905 			us->max_lun = usb_stor_Bulk_max_lun(us);
906 			mutex_unlock(&us->dev_mutex);
907 		}
908 		scsi_scan_host(us_to_host(us));
909 		printk(KERN_DEBUG "usb-storage: device scan complete\n");
910 
911 		/* Should we unbind if no devices were detected? */
912 	}
913 
914 	scsi_host_put(us_to_host(us));
915 	complete_and_exit(&threads_gone, 0);
916 }
917 
918 
919 /* Probe to see if we can drive a newly-connected USB device */
920 static int storage_probe(struct usb_interface *intf,
921 			 const struct usb_device_id *id)
922 {
923 	struct Scsi_Host *host;
924 	struct us_data *us;
925 	int result;
926 	struct task_struct *th;
927 
928 	if (usb_usual_check_type(id, USB_US_TYPE_STOR))
929 		return -ENXIO;
930 
931 	US_DEBUGP("USB Mass Storage device detected\n");
932 
933 	/*
934 	 * Ask the SCSI layer to allocate a host structure, with extra
935 	 * space at the end for our private us_data structure.
936 	 */
937 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
938 	if (!host) {
939 		printk(KERN_WARNING USB_STORAGE
940 			"Unable to allocate the scsi host\n");
941 		return -ENOMEM;
942 	}
943 
944 	us = host_to_us(host);
945 	memset(us, 0, sizeof(struct us_data));
946 	mutex_init(&(us->dev_mutex));
947 	init_MUTEX_LOCKED(&(us->sema));
948 	init_completion(&(us->notify));
949 	init_waitqueue_head(&us->delay_wait);
950 
951 	/* Associate the us_data structure with the USB device */
952 	result = associate_dev(us, intf);
953 	if (result)
954 		goto BadDevice;
955 
956 	/*
957 	 * Get the unusual_devs entries and the descriptors
958 	 *
959 	 * id_index is calculated in the declaration to be the index number
960 	 * of the match from the usb_device_id table, so we can find the
961 	 * corresponding entry in the private table.
962 	 */
963 	get_device_info(us, id);
964 
965 	/* Get the transport, protocol, and pipe settings */
966 	result = get_transport(us);
967 	if (result)
968 		goto BadDevice;
969 	result = get_protocol(us);
970 	if (result)
971 		goto BadDevice;
972 	result = get_pipes(us);
973 	if (result)
974 		goto BadDevice;
975 
976 	/* Acquire all the other resources and add the host */
977 	result = usb_stor_acquire_resources(us);
978 	if (result)
979 		goto BadDevice;
980 	result = scsi_add_host(host, &intf->dev);
981 	if (result) {
982 		printk(KERN_WARNING USB_STORAGE
983 			"Unable to add the scsi host\n");
984 		goto BadDevice;
985 	}
986 
987 	/* Start up the thread for delayed SCSI-device scanning */
988 	th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
989 	if (IS_ERR(th)) {
990 		printk(KERN_WARNING USB_STORAGE
991 		       "Unable to start the device-scanning thread\n");
992 		quiesce_and_remove_host(us);
993 		result = PTR_ERR(th);
994 		goto BadDevice;
995 	}
996 
997 	/* Take a reference to the host for the scanning thread and
998 	 * count it among all the threads we have launched.  Then
999 	 * start it up. */
1000 	scsi_host_get(us_to_host(us));
1001 	atomic_inc(&total_threads);
1002 	wake_up_process(th);
1003 
1004 	return 0;
1005 
1006 	/* We come here if there are any problems */
1007 BadDevice:
1008 	US_DEBUGP("storage_probe() failed\n");
1009 	release_everything(us);
1010 	return result;
1011 }
1012 
1013 /* Handle a disconnect event from the USB core */
1014 static void storage_disconnect(struct usb_interface *intf)
1015 {
1016 	struct us_data *us = usb_get_intfdata(intf);
1017 
1018 	US_DEBUGP("storage_disconnect() called\n");
1019 	quiesce_and_remove_host(us);
1020 	release_everything(us);
1021 }
1022 
1023 /***********************************************************************
1024  * Initialization and registration
1025  ***********************************************************************/
1026 
1027 static struct usb_driver usb_storage_driver = {
1028 	.name =		"usb-storage",
1029 	.probe =	storage_probe,
1030 	.disconnect =	storage_disconnect,
1031 #ifdef CONFIG_PM
1032 	.suspend =	storage_suspend,
1033 	.resume =	storage_resume,
1034 #endif
1035 	.pre_reset =	storage_pre_reset,
1036 	.post_reset =	storage_post_reset,
1037 	.id_table =	storage_usb_ids,
1038 };
1039 
1040 static int __init usb_stor_init(void)
1041 {
1042 	int retval;
1043 	printk(KERN_INFO "Initializing USB Mass Storage driver...\n");
1044 
1045 	/* register the driver, return usb_register return code if error */
1046 	retval = usb_register(&usb_storage_driver);
1047 	if (retval == 0) {
1048 		printk(KERN_INFO "USB Mass Storage support registered.\n");
1049 		usb_usual_set_present(USB_US_TYPE_STOR);
1050 	}
1051 	return retval;
1052 }
1053 
1054 static void __exit usb_stor_exit(void)
1055 {
1056 	US_DEBUGP("usb_stor_exit() called\n");
1057 
1058 	/* Deregister the driver
1059 	 * This will cause disconnect() to be called for each
1060 	 * attached unit
1061 	 */
1062 	US_DEBUGP("-- calling usb_deregister()\n");
1063 	usb_deregister(&usb_storage_driver) ;
1064 
1065 	/* Don't return until all of our control and scanning threads
1066 	 * have exited.  Since each thread signals threads_gone as its
1067 	 * last act, we have to call wait_for_completion the right number
1068 	 * of times.
1069 	 */
1070 	while (atomic_read(&total_threads) > 0) {
1071 		wait_for_completion(&threads_gone);
1072 		atomic_dec(&total_threads);
1073 	}
1074 
1075 	usb_usual_clear_present(USB_US_TYPE_STOR);
1076 }
1077 
1078 module_init(usb_stor_init);
1079 module_exit(usb_stor_exit);
1080