xref: /linux/drivers/usb/storage/usb.c (revision dfe0d3ba20e860d0b9a16c4c6524180b8f93be05)
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 #include <linux/utsrelease.h>
59 
60 #include <scsi/scsi.h>
61 #include <scsi/scsi_cmnd.h>
62 #include <scsi/scsi_device.h>
63 
64 #include "usb.h"
65 #include "scsiglue.h"
66 #include "transport.h"
67 #include "protocol.h"
68 #include "debug.h"
69 #include "initializers.h"
70 
71 #ifdef CONFIG_USB_STORAGE_USBAT
72 #include "shuttle_usbat.h"
73 #endif
74 #ifdef CONFIG_USB_STORAGE_SDDR09
75 #include "sddr09.h"
76 #endif
77 #ifdef CONFIG_USB_STORAGE_SDDR55
78 #include "sddr55.h"
79 #endif
80 #ifdef CONFIG_USB_STORAGE_DPCM
81 #include "dpcm.h"
82 #endif
83 #ifdef CONFIG_USB_STORAGE_FREECOM
84 #include "freecom.h"
85 #endif
86 #ifdef CONFIG_USB_STORAGE_ISD200
87 #include "isd200.h"
88 #endif
89 #ifdef CONFIG_USB_STORAGE_DATAFAB
90 #include "datafab.h"
91 #endif
92 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
93 #include "jumpshot.h"
94 #endif
95 #ifdef CONFIG_USB_STORAGE_ONETOUCH
96 #include "onetouch.h"
97 #endif
98 #ifdef CONFIG_USB_STORAGE_ALAUDA
99 #include "alauda.h"
100 #endif
101 #ifdef CONFIG_USB_STORAGE_KARMA
102 #include "karma.h"
103 #endif
104 
105 /* Some informational data */
106 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
107 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
108 MODULE_LICENSE("GPL");
109 
110 static unsigned int delay_use = 5;
111 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
112 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
113 
114 
115 /* These are used to make sure the module doesn't unload before all the
116  * threads have exited.
117  */
118 static atomic_t total_threads = ATOMIC_INIT(0);
119 static DECLARE_COMPLETION(threads_gone);
120 
121 
122 /*
123  * The entries in this table correspond, line for line,
124  * with the entries of us_unusual_dev_list[].
125  */
126 #ifndef CONFIG_USB_LIBUSUAL
127 
128 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
129 		    vendorName, productName,useProtocol, useTransport, \
130 		    initFunction, flags) \
131 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin,bcdDeviceMax), \
132   .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }
133 
134 #define USUAL_DEV(useProto, useTrans, useType) \
135 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, useProto, useTrans), \
136   .driver_info = (USB_US_TYPE_STOR<<24) }
137 
138 static struct usb_device_id storage_usb_ids [] = {
139 
140 #	include "unusual_devs.h"
141 #undef UNUSUAL_DEV
142 #undef USUAL_DEV
143 	/* Terminating entry */
144 	{ }
145 };
146 
147 MODULE_DEVICE_TABLE (usb, storage_usb_ids);
148 #endif /* CONFIG_USB_LIBUSUAL */
149 
150 /* This is the list of devices we recognize, along with their flag data */
151 
152 /* The vendor name should be kept at eight characters or less, and
153  * the product name should be kept at 16 characters or less. If a device
154  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
155  * normally generated by a device thorugh the INQUIRY response will be
156  * taken from this list, and this is the reason for the above size
157  * restriction. However, if the flag is not present, then you
158  * are free to use as many characters as you like.
159  */
160 
161 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
162 		    vendor_name, product_name, use_protocol, use_transport, \
163 		    init_function, Flags) \
164 { \
165 	.vendorName = vendor_name,	\
166 	.productName = product_name,	\
167 	.useProtocol = use_protocol,	\
168 	.useTransport = use_transport,	\
169 	.initFunction = init_function,	\
170 }
171 
172 #define USUAL_DEV(use_protocol, use_transport, use_type) \
173 { \
174 	.useProtocol = use_protocol,	\
175 	.useTransport = use_transport,	\
176 }
177 
178 static struct us_unusual_dev us_unusual_dev_list[] = {
179 #	include "unusual_devs.h"
180 #	undef UNUSUAL_DEV
181 #	undef USUAL_DEV
182 
183 	/* Terminating entry */
184 	{ NULL }
185 };
186 
187 
188 #ifdef CONFIG_PM	/* Minimal support for suspend and resume */
189 
190 static int storage_suspend(struct usb_interface *iface, pm_message_t message)
191 {
192 	struct us_data *us = usb_get_intfdata(iface);
193 
194 	/* Wait until no command is running */
195 	mutex_lock(&us->dev_mutex);
196 
197 	US_DEBUGP("%s\n", __FUNCTION__);
198 	if (us->suspend_resume_hook)
199 		(us->suspend_resume_hook)(us, US_SUSPEND);
200 	iface->dev.power.power_state.event = message.event;
201 
202 	/* When runtime PM is working, we'll set a flag to indicate
203 	 * whether we should autoresume when a SCSI request arrives. */
204 
205 	mutex_unlock(&us->dev_mutex);
206 	return 0;
207 }
208 
209 static int storage_resume(struct usb_interface *iface)
210 {
211 	struct us_data *us = usb_get_intfdata(iface);
212 
213 	mutex_lock(&us->dev_mutex);
214 
215 	US_DEBUGP("%s\n", __FUNCTION__);
216 	if (us->suspend_resume_hook)
217 		(us->suspend_resume_hook)(us, US_RESUME);
218 	iface->dev.power.power_state.event = PM_EVENT_ON;
219 
220 	mutex_unlock(&us->dev_mutex);
221 	return 0;
222 }
223 
224 #endif /* CONFIG_PM */
225 
226 /*
227  * The next two routines get called just before and just after
228  * a USB port reset, whether from this driver or a different one.
229  */
230 
231 static void storage_pre_reset(struct usb_interface *iface)
232 {
233 	struct us_data *us = usb_get_intfdata(iface);
234 
235 	US_DEBUGP("%s\n", __FUNCTION__);
236 
237 	/* Make sure no command runs during the reset */
238 	mutex_lock(&us->dev_mutex);
239 }
240 
241 static void storage_post_reset(struct usb_interface *iface)
242 {
243 	struct us_data *us = usb_get_intfdata(iface);
244 
245 	US_DEBUGP("%s\n", __FUNCTION__);
246 
247 	/* Report the reset to the SCSI core */
248 	scsi_lock(us_to_host(us));
249 	usb_stor_report_bus_reset(us);
250 	scsi_unlock(us_to_host(us));
251 
252 	/* FIXME: Notify the subdrivers that they need to reinitialize
253 	 * the device */
254 	mutex_unlock(&us->dev_mutex);
255 }
256 
257 /*
258  * fill_inquiry_response takes an unsigned char array (which must
259  * be at least 36 characters) and populates the vendor name,
260  * product name, and revision fields. Then the array is copied
261  * into the SCSI command's response buffer (oddly enough
262  * called request_buffer). data_len contains the length of the
263  * data array, which again must be at least 36.
264  */
265 
266 void fill_inquiry_response(struct us_data *us, unsigned char *data,
267 		unsigned int data_len)
268 {
269 	if (data_len<36) // You lose.
270 		return;
271 
272 	if(data[0]&0x20) { /* USB device currently not connected. Return
273 			      peripheral qualifier 001b ("...however, the
274 			      physical device is not currently connected
275 			      to this logical unit") and leave vendor and
276 			      product identification empty. ("If the target
277 			      does store some of the INQUIRY data on the
278 			      device, it may return zeros or ASCII spaces
279 			      (20h) in those fields until the data is
280 			      available from the device."). */
281 		memset(data+8,0,28);
282 	} else {
283 		u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
284 		memcpy(data+8, us->unusual_dev->vendorName,
285 			strlen(us->unusual_dev->vendorName) > 8 ? 8 :
286 			strlen(us->unusual_dev->vendorName));
287 		memcpy(data+16, us->unusual_dev->productName,
288 			strlen(us->unusual_dev->productName) > 16 ? 16 :
289 			strlen(us->unusual_dev->productName));
290 		data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
291 		data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
292 		data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
293 		data[35] = 0x30 + ((bcdDevice) & 0x0F);
294 	}
295 
296 	usb_stor_set_xfer_buf(data, data_len, us->srb);
297 }
298 
299 static int usb_stor_control_thread(void * __us)
300 {
301 	struct us_data *us = (struct us_data *)__us;
302 	struct Scsi_Host *host = us_to_host(us);
303 
304 	current->flags |= PF_NOFREEZE;
305 
306 	for(;;) {
307 		US_DEBUGP("*** thread sleeping.\n");
308 		if(down_interruptible(&us->sema))
309 			break;
310 
311 		US_DEBUGP("*** thread awakened.\n");
312 
313 		/* lock the device pointers */
314 		mutex_lock(&(us->dev_mutex));
315 
316 		/* if the device has disconnected, we are free to exit */
317 		if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
318 			US_DEBUGP("-- exiting\n");
319 			mutex_unlock(&us->dev_mutex);
320 			break;
321 		}
322 
323 		/* lock access to the state */
324 		scsi_lock(host);
325 
326 		/* has the command timed out *already* ? */
327 		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
328 			us->srb->result = DID_ABORT << 16;
329 			goto SkipForAbort;
330 		}
331 
332 		scsi_unlock(host);
333 
334 		/* reject the command if the direction indicator
335 		 * is UNKNOWN
336 		 */
337 		if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
338 			US_DEBUGP("UNKNOWN data direction\n");
339 			us->srb->result = DID_ERROR << 16;
340 		}
341 
342 		/* reject if target != 0 or if LUN is higher than
343 		 * the maximum known LUN
344 		 */
345 		else if (us->srb->device->id &&
346 				!(us->flags & US_FL_SCM_MULT_TARG)) {
347 			US_DEBUGP("Bad target number (%d:%d)\n",
348 				  us->srb->device->id, us->srb->device->lun);
349 			us->srb->result = DID_BAD_TARGET << 16;
350 		}
351 
352 		else if (us->srb->device->lun > us->max_lun) {
353 			US_DEBUGP("Bad LUN (%d:%d)\n",
354 				  us->srb->device->id, us->srb->device->lun);
355 			us->srb->result = DID_BAD_TARGET << 16;
356 		}
357 
358 		/* Handle those devices which need us to fake
359 		 * their inquiry data */
360 		else if ((us->srb->cmnd[0] == INQUIRY) &&
361 			    (us->flags & US_FL_FIX_INQUIRY)) {
362 			unsigned char data_ptr[36] = {
363 			    0x00, 0x80, 0x02, 0x02,
364 			    0x1F, 0x00, 0x00, 0x00};
365 
366 			US_DEBUGP("Faking INQUIRY command\n");
367 			fill_inquiry_response(us, data_ptr, 36);
368 			us->srb->result = SAM_STAT_GOOD;
369 		}
370 
371 		/* we've got a command, let's do it! */
372 		else {
373 			US_DEBUG(usb_stor_show_command(us->srb));
374 			us->proto_handler(us->srb, us);
375 		}
376 
377 		/* lock access to the state */
378 		scsi_lock(host);
379 
380 		/* did the command already complete because of a disconnect? */
381 		if (!us->srb)
382 			;		/* nothing to do */
383 
384 		/* indicate that the command is done */
385 		else if (us->srb->result != DID_ABORT << 16) {
386 			US_DEBUGP("scsi cmd done, result=0x%x\n",
387 				   us->srb->result);
388 			us->srb->scsi_done(us->srb);
389 		} else {
390 SkipForAbort:
391 			US_DEBUGP("scsi command aborted\n");
392 		}
393 
394 		/* If an abort request was received we need to signal that
395 		 * the abort has finished.  The proper test for this is
396 		 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
397 		 * the timeout might have occurred after the command had
398 		 * already completed with a different result code. */
399 		if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
400 			complete(&(us->notify));
401 
402 			/* Allow USB transfers to resume */
403 			clear_bit(US_FLIDX_ABORTING, &us->flags);
404 			clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
405 		}
406 
407 		/* finished working on this command */
408 		us->srb = NULL;
409 		scsi_unlock(host);
410 
411 		/* unlock the device pointers */
412 		mutex_unlock(&us->dev_mutex);
413 	} /* for (;;) */
414 
415 	scsi_host_put(host);
416 
417 	/* notify the exit routine that we're actually exiting now
418 	 *
419 	 * complete()/wait_for_completion() is similar to up()/down(),
420 	 * except that complete() is safe in the case where the structure
421 	 * is getting deleted in a parallel mode of execution (i.e. just
422 	 * after the down() -- that's necessary for the thread-shutdown
423 	 * case.
424 	 *
425 	 * complete_and_exit() goes even further than this -- it is safe in
426 	 * the case that the thread of the caller is going away (not just
427 	 * the structure) -- this is necessary for the module-remove case.
428 	 * This is important in preemption kernels, which transfer the flow
429 	 * of execution immediately upon a complete().
430 	 */
431 	complete_and_exit(&threads_gone, 0);
432 }
433 
434 /***********************************************************************
435  * Device probing and disconnecting
436  ***********************************************************************/
437 
438 /* Associate our private data with the USB device */
439 static int associate_dev(struct us_data *us, struct usb_interface *intf)
440 {
441 	US_DEBUGP("-- %s\n", __FUNCTION__);
442 
443 	/* Fill in the device-related fields */
444 	us->pusb_dev = interface_to_usbdev(intf);
445 	us->pusb_intf = intf;
446 	us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
447 	US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
448 			le16_to_cpu(us->pusb_dev->descriptor.idVendor),
449 			le16_to_cpu(us->pusb_dev->descriptor.idProduct),
450 			le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
451 	US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
452 			intf->cur_altsetting->desc.bInterfaceSubClass,
453 			intf->cur_altsetting->desc.bInterfaceProtocol);
454 
455 	/* Store our private data in the interface */
456 	usb_set_intfdata(intf, us);
457 
458 	/* Allocate the device-related DMA-mapped buffers */
459 	us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
460 			GFP_KERNEL, &us->cr_dma);
461 	if (!us->cr) {
462 		US_DEBUGP("usb_ctrlrequest allocation failed\n");
463 		return -ENOMEM;
464 	}
465 
466 	us->iobuf = usb_buffer_alloc(us->pusb_dev, US_IOBUF_SIZE,
467 			GFP_KERNEL, &us->iobuf_dma);
468 	if (!us->iobuf) {
469 		US_DEBUGP("I/O buffer allocation failed\n");
470 		return -ENOMEM;
471 	}
472 
473 	us->sensebuf = kmalloc(US_SENSE_SIZE, GFP_KERNEL);
474 	if (!us->sensebuf) {
475 		US_DEBUGP("Sense buffer allocation failed\n");
476 		return -ENOMEM;
477 	}
478 	return 0;
479 }
480 
481 /* Find an unusual_dev descriptor (always succeeds in the current code) */
482 static struct us_unusual_dev *find_unusual(const struct usb_device_id *id)
483 {
484 	const int id_index = id - storage_usb_ids;
485 	return &us_unusual_dev_list[id_index];
486 }
487 
488 /* Get the unusual_devs entries and the string descriptors */
489 static int get_device_info(struct us_data *us, const struct usb_device_id *id)
490 {
491 	struct usb_device *dev = us->pusb_dev;
492 	struct usb_interface_descriptor *idesc =
493 		&us->pusb_intf->cur_altsetting->desc;
494 	struct us_unusual_dev *unusual_dev = find_unusual(id);
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 = USB_US_ORIG_FLAGS(id->driver_info);
505 
506 	if (us->flags & US_FL_IGNORE_DEVICE) {
507 		printk(KERN_INFO USB_STORAGE "device ignored\n");
508 		return -ENODEV;
509 	}
510 
511 	/*
512 	 * This flag is only needed when we're in high-speed, so let's
513 	 * disable it if we're in full-speed
514 	 */
515 	if (dev->speed != USB_SPEED_HIGH)
516 		us->flags &= ~US_FL_GO_SLOW;
517 
518 	/* Log a message if a non-generic unusual_dev entry contains an
519 	 * unnecessary subclass or protocol override.  This may stimulate
520 	 * reports from users that will help us remove unneeded entries
521 	 * from the unusual_devs.h table.
522 	 */
523 	if (id->idVendor || id->idProduct) {
524 		static const char *msgs[3] = {
525 			"an unneeded SubClass entry",
526 			"an unneeded Protocol entry",
527 			"unneeded SubClass and Protocol entries"};
528 		struct usb_device_descriptor *ddesc = &dev->descriptor;
529 		int msg = -1;
530 
531 		if (unusual_dev->useProtocol != US_SC_DEVICE &&
532 			us->subclass == idesc->bInterfaceSubClass)
533 			msg += 1;
534 		if (unusual_dev->useTransport != US_PR_DEVICE &&
535 			us->protocol == idesc->bInterfaceProtocol)
536 			msg += 2;
537 		if (msg >= 0 && !(us->flags & US_FL_NEED_OVERRIDE))
538 			printk(KERN_NOTICE USB_STORAGE "This device "
539 				"(%04x,%04x,%04x S %02x P %02x)"
540 				" has %s in unusual_devs.h (kernel"
541 				" %s)\n"
542 				"   Please send a copy of this message to "
543 				"<linux-usb-devel@lists.sourceforge.net>\n",
544 				le16_to_cpu(ddesc->idVendor),
545 				le16_to_cpu(ddesc->idProduct),
546 				le16_to_cpu(ddesc->bcdDevice),
547 				idesc->bInterfaceSubClass,
548 				idesc->bInterfaceProtocol,
549 				msgs[msg],
550 				UTS_RELEASE);
551 	}
552 
553 	return 0;
554 }
555 
556 /* Get the transport settings */
557 static int get_transport(struct us_data *us)
558 {
559 	switch (us->protocol) {
560 	case US_PR_CB:
561 		us->transport_name = "Control/Bulk";
562 		us->transport = usb_stor_CB_transport;
563 		us->transport_reset = usb_stor_CB_reset;
564 		us->max_lun = 7;
565 		break;
566 
567 	case US_PR_CBI:
568 		us->transport_name = "Control/Bulk/Interrupt";
569 		us->transport = usb_stor_CBI_transport;
570 		us->transport_reset = usb_stor_CB_reset;
571 		us->max_lun = 7;
572 		break;
573 
574 	case US_PR_BULK:
575 		us->transport_name = "Bulk";
576 		us->transport = usb_stor_Bulk_transport;
577 		us->transport_reset = usb_stor_Bulk_reset;
578 		break;
579 
580 #ifdef CONFIG_USB_STORAGE_USBAT
581 	case US_PR_USBAT:
582 		us->transport_name = "Shuttle USBAT";
583 		us->transport = usbat_transport;
584 		us->transport_reset = usb_stor_CB_reset;
585 		us->max_lun = 1;
586 		break;
587 #endif
588 
589 #ifdef CONFIG_USB_STORAGE_SDDR09
590 	case US_PR_EUSB_SDDR09:
591 		us->transport_name = "EUSB/SDDR09";
592 		us->transport = sddr09_transport;
593 		us->transport_reset = usb_stor_CB_reset;
594 		us->max_lun = 0;
595 		break;
596 #endif
597 
598 #ifdef CONFIG_USB_STORAGE_SDDR55
599 	case US_PR_SDDR55:
600 		us->transport_name = "SDDR55";
601 		us->transport = sddr55_transport;
602 		us->transport_reset = sddr55_reset;
603 		us->max_lun = 0;
604 		break;
605 #endif
606 
607 #ifdef CONFIG_USB_STORAGE_DPCM
608 	case US_PR_DPCM_USB:
609 		us->transport_name = "Control/Bulk-EUSB/SDDR09";
610 		us->transport = dpcm_transport;
611 		us->transport_reset = usb_stor_CB_reset;
612 		us->max_lun = 1;
613 		break;
614 #endif
615 
616 #ifdef CONFIG_USB_STORAGE_FREECOM
617 	case US_PR_FREECOM:
618 		us->transport_name = "Freecom";
619 		us->transport = freecom_transport;
620 		us->transport_reset = usb_stor_freecom_reset;
621 		us->max_lun = 0;
622 		break;
623 #endif
624 
625 #ifdef CONFIG_USB_STORAGE_DATAFAB
626 	case US_PR_DATAFAB:
627 		us->transport_name  = "Datafab Bulk-Only";
628 		us->transport = datafab_transport;
629 		us->transport_reset = usb_stor_Bulk_reset;
630 		us->max_lun = 1;
631 		break;
632 #endif
633 
634 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
635 	case US_PR_JUMPSHOT:
636 		us->transport_name  = "Lexar Jumpshot Control/Bulk";
637 		us->transport = jumpshot_transport;
638 		us->transport_reset = usb_stor_Bulk_reset;
639 		us->max_lun = 1;
640 		break;
641 #endif
642 
643 #ifdef CONFIG_USB_STORAGE_ALAUDA
644 	case US_PR_ALAUDA:
645 		us->transport_name  = "Alauda Control/Bulk";
646 		us->transport = alauda_transport;
647 		us->transport_reset = usb_stor_Bulk_reset;
648 		us->max_lun = 1;
649 		break;
650 #endif
651 
652 #ifdef CONFIG_USB_STORAGE_KARMA
653 	case US_PR_KARMA:
654 		us->transport_name = "Rio Karma/Bulk";
655 		us->transport = rio_karma_transport;
656 		us->transport_reset = usb_stor_Bulk_reset;
657 		break;
658 #endif
659 
660 	default:
661 		return -EIO;
662 	}
663 	US_DEBUGP("Transport: %s\n", us->transport_name);
664 
665 	/* fix for single-lun devices */
666 	if (us->flags & US_FL_SINGLE_LUN)
667 		us->max_lun = 0;
668 	return 0;
669 }
670 
671 /* Get the protocol settings */
672 static int get_protocol(struct us_data *us)
673 {
674 	switch (us->subclass) {
675 	case US_SC_RBC:
676 		us->protocol_name = "Reduced Block Commands (RBC)";
677 		us->proto_handler = usb_stor_transparent_scsi_command;
678 		break;
679 
680 	case US_SC_8020:
681 		us->protocol_name = "8020i";
682 		us->proto_handler = usb_stor_ATAPI_command;
683 		us->max_lun = 0;
684 		break;
685 
686 	case US_SC_QIC:
687 		us->protocol_name = "QIC-157";
688 		us->proto_handler = usb_stor_qic157_command;
689 		us->max_lun = 0;
690 		break;
691 
692 	case US_SC_8070:
693 		us->protocol_name = "8070i";
694 		us->proto_handler = usb_stor_ATAPI_command;
695 		us->max_lun = 0;
696 		break;
697 
698 	case US_SC_SCSI:
699 		us->protocol_name = "Transparent SCSI";
700 		us->proto_handler = usb_stor_transparent_scsi_command;
701 		break;
702 
703 	case US_SC_UFI:
704 		us->protocol_name = "Uniform Floppy Interface (UFI)";
705 		us->proto_handler = usb_stor_ufi_command;
706 		break;
707 
708 #ifdef CONFIG_USB_STORAGE_ISD200
709 	case US_SC_ISD200:
710 		us->protocol_name = "ISD200 ATA/ATAPI";
711 		us->proto_handler = isd200_ata_command;
712 		break;
713 #endif
714 
715 	default:
716 		return -EIO;
717 	}
718 	US_DEBUGP("Protocol: %s\n", us->protocol_name);
719 	return 0;
720 }
721 
722 /* Get the pipe settings */
723 static int get_pipes(struct us_data *us)
724 {
725 	struct usb_host_interface *altsetting =
726 		us->pusb_intf->cur_altsetting;
727 	int i;
728 	struct usb_endpoint_descriptor *ep;
729 	struct usb_endpoint_descriptor *ep_in = NULL;
730 	struct usb_endpoint_descriptor *ep_out = NULL;
731 	struct usb_endpoint_descriptor *ep_int = NULL;
732 
733 	/*
734 	 * Find the endpoints we need.
735 	 * We are expecting a minimum of 2 endpoints - in and out (bulk).
736 	 * An optional interrupt is OK (necessary for CBI protocol).
737 	 * We will ignore any others.
738 	 */
739 	for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
740 		ep = &altsetting->endpoint[i].desc;
741 
742 		/* Is it a BULK endpoint? */
743 		if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
744 				== USB_ENDPOINT_XFER_BULK) {
745 			/* BULK in or out? */
746 			if (ep->bEndpointAddress & USB_DIR_IN)
747 				ep_in = ep;
748 			else
749 				ep_out = ep;
750 		}
751 
752 		/* Is it an interrupt endpoint? */
753 		else if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
754 				== USB_ENDPOINT_XFER_INT) {
755 			ep_int = ep;
756 		}
757 	}
758 
759 	if (!ep_in || !ep_out || (us->protocol == US_PR_CBI && !ep_int)) {
760 		US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
761 		return -EIO;
762 	}
763 
764 	/* Calculate and store the pipe values */
765 	us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
766 	us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
767 	us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
768 		ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
769 	us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
770 		ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
771 	if (ep_int) {
772 		us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
773 			ep_int->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
774 		us->ep_bInterval = ep_int->bInterval;
775 	}
776 	return 0;
777 }
778 
779 /* Initialize all the dynamic resources we need */
780 static int usb_stor_acquire_resources(struct us_data *us)
781 {
782 	int p;
783 	struct task_struct *th;
784 
785 	us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
786 	if (!us->current_urb) {
787 		US_DEBUGP("URB allocation failed\n");
788 		return -ENOMEM;
789 	}
790 
791 	/* Just before we start our control thread, initialize
792 	 * the device if it needs initialization */
793 	if (us->unusual_dev->initFunction) {
794 		p = us->unusual_dev->initFunction(us);
795 		if (p)
796 			return p;
797 	}
798 
799 	/* Start up our control thread */
800 	th = kthread_create(usb_stor_control_thread, us, "usb-storage");
801 	if (IS_ERR(th)) {
802 		printk(KERN_WARNING USB_STORAGE
803 		       "Unable to start control thread\n");
804 		return PTR_ERR(th);
805 	}
806 
807 	/* Take a reference to the host for the control thread and
808 	 * count it among all the threads we have launched.  Then
809 	 * start it up. */
810 	scsi_host_get(us_to_host(us));
811 	atomic_inc(&total_threads);
812 	wake_up_process(th);
813 
814 	return 0;
815 }
816 
817 /* Release all our dynamic resources */
818 static void usb_stor_release_resources(struct us_data *us)
819 {
820 	US_DEBUGP("-- %s\n", __FUNCTION__);
821 
822 	/* Tell the control thread to exit.  The SCSI host must
823 	 * already have been removed so it won't try to queue
824 	 * any more commands.
825 	 */
826 	US_DEBUGP("-- sending exit command to thread\n");
827 	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
828 	up(&us->sema);
829 
830 	/* Call the destructor routine, if it exists */
831 	if (us->extra_destructor) {
832 		US_DEBUGP("-- calling extra_destructor()\n");
833 		us->extra_destructor(us->extra);
834 	}
835 
836 	/* Free the extra data and the URB */
837 	kfree(us->extra);
838 	usb_free_urb(us->current_urb);
839 }
840 
841 /* Dissociate from the USB device */
842 static void dissociate_dev(struct us_data *us)
843 {
844 	US_DEBUGP("-- %s\n", __FUNCTION__);
845 
846 	kfree(us->sensebuf);
847 
848 	/* Free the device-related DMA-mapped buffers */
849 	if (us->cr)
850 		usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
851 				us->cr_dma);
852 	if (us->iobuf)
853 		usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
854 				us->iobuf_dma);
855 
856 	/* Remove our private data from the interface */
857 	usb_set_intfdata(us->pusb_intf, NULL);
858 }
859 
860 /* First stage of disconnect processing: stop all commands and remove
861  * the host */
862 static void quiesce_and_remove_host(struct us_data *us)
863 {
864 	struct Scsi_Host *host = us_to_host(us);
865 
866 	/* Prevent new USB transfers, stop the current command, and
867 	 * interrupt a SCSI-scan or device-reset delay */
868 	scsi_lock(host);
869 	set_bit(US_FLIDX_DISCONNECTING, &us->flags);
870 	scsi_unlock(host);
871 	usb_stor_stop_transport(us);
872 	wake_up(&us->delay_wait);
873 
874 	/* It doesn't matter if the SCSI-scanning thread is still running.
875 	 * The thread will exit when it sees the DISCONNECTING flag. */
876 
877 	/* queuecommand won't accept any new commands and the control
878 	 * thread won't execute a previously-queued command.  If there
879 	 * is such a command pending, complete it with an error. */
880 	mutex_lock(&us->dev_mutex);
881 	if (us->srb) {
882 		us->srb->result = DID_NO_CONNECT << 16;
883 		scsi_lock(host);
884 		us->srb->scsi_done(us->srb);
885 		us->srb = NULL;
886 		scsi_unlock(host);
887 	}
888 	mutex_unlock(&us->dev_mutex);
889 
890 	/* Now we own no commands so it's safe to remove the SCSI host */
891 	scsi_remove_host(host);
892 }
893 
894 /* Second stage of disconnect processing: deallocate all resources */
895 static void release_everything(struct us_data *us)
896 {
897 	usb_stor_release_resources(us);
898 	dissociate_dev(us);
899 
900 	/* Drop our reference to the host; the SCSI core will free it
901 	 * (and "us" along with it) when the refcount becomes 0. */
902 	scsi_host_put(us_to_host(us));
903 }
904 
905 /* Thread to carry out delayed SCSI-device scanning */
906 static int usb_stor_scan_thread(void * __us)
907 {
908 	struct us_data *us = (struct us_data *)__us;
909 
910 	printk(KERN_DEBUG
911 		"usb-storage: device found at %d\n", us->pusb_dev->devnum);
912 
913 	/* Wait for the timeout to expire or for a disconnect */
914 	if (delay_use > 0) {
915 		printk(KERN_DEBUG "usb-storage: waiting for device "
916 				"to settle before scanning\n");
917 retry:
918 		wait_event_interruptible_timeout(us->delay_wait,
919 				test_bit(US_FLIDX_DISCONNECTING, &us->flags),
920 				delay_use * HZ);
921 		if (try_to_freeze())
922 			goto retry;
923 	}
924 
925 	/* If the device is still connected, perform the scanning */
926 	if (!test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
927 
928 		/* For bulk-only devices, determine the max LUN value */
929 		if (us->protocol == US_PR_BULK &&
930 				!(us->flags & US_FL_SINGLE_LUN)) {
931 			mutex_lock(&us->dev_mutex);
932 			us->max_lun = usb_stor_Bulk_max_lun(us);
933 			mutex_unlock(&us->dev_mutex);
934 		}
935 		scsi_scan_host(us_to_host(us));
936 		printk(KERN_DEBUG "usb-storage: device scan complete\n");
937 
938 		/* Should we unbind if no devices were detected? */
939 	}
940 
941 	scsi_host_put(us_to_host(us));
942 	complete_and_exit(&threads_gone, 0);
943 }
944 
945 
946 /* Probe to see if we can drive a newly-connected USB device */
947 static int storage_probe(struct usb_interface *intf,
948 			 const struct usb_device_id *id)
949 {
950 	struct Scsi_Host *host;
951 	struct us_data *us;
952 	int result;
953 	struct task_struct *th;
954 
955 	if (usb_usual_check_type(id, USB_US_TYPE_STOR))
956 		return -ENXIO;
957 
958 	US_DEBUGP("USB Mass Storage device detected\n");
959 
960 	/*
961 	 * Ask the SCSI layer to allocate a host structure, with extra
962 	 * space at the end for our private us_data structure.
963 	 */
964 	host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
965 	if (!host) {
966 		printk(KERN_WARNING USB_STORAGE
967 			"Unable to allocate the scsi host\n");
968 		return -ENOMEM;
969 	}
970 
971 	us = host_to_us(host);
972 	memset(us, 0, sizeof(struct us_data));
973 	mutex_init(&(us->dev_mutex));
974 	init_MUTEX_LOCKED(&(us->sema));
975 	init_completion(&(us->notify));
976 	init_waitqueue_head(&us->delay_wait);
977 
978 	/* Associate the us_data structure with the USB device */
979 	result = associate_dev(us, intf);
980 	if (result)
981 		goto BadDevice;
982 
983 	/*
984 	 * Get the unusual_devs entries and the descriptors
985 	 *
986 	 * id_index is calculated in the declaration to be the index number
987 	 * of the match from the usb_device_id table, so we can find the
988 	 * corresponding entry in the private table.
989 	 */
990 	result = get_device_info(us, id);
991 	if (result)
992 		goto BadDevice;
993 
994 	/* Get the transport, protocol, and pipe settings */
995 	result = get_transport(us);
996 	if (result)
997 		goto BadDevice;
998 	result = get_protocol(us);
999 	if (result)
1000 		goto BadDevice;
1001 	result = get_pipes(us);
1002 	if (result)
1003 		goto BadDevice;
1004 
1005 	/* Acquire all the other resources and add the host */
1006 	result = usb_stor_acquire_resources(us);
1007 	if (result)
1008 		goto BadDevice;
1009 	result = scsi_add_host(host, &intf->dev);
1010 	if (result) {
1011 		printk(KERN_WARNING USB_STORAGE
1012 			"Unable to add the scsi host\n");
1013 		goto BadDevice;
1014 	}
1015 
1016 	/* Start up the thread for delayed SCSI-device scanning */
1017 	th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
1018 	if (IS_ERR(th)) {
1019 		printk(KERN_WARNING USB_STORAGE
1020 		       "Unable to start the device-scanning thread\n");
1021 		quiesce_and_remove_host(us);
1022 		result = PTR_ERR(th);
1023 		goto BadDevice;
1024 	}
1025 
1026 	/* Take a reference to the host for the scanning thread and
1027 	 * count it among all the threads we have launched.  Then
1028 	 * start it up. */
1029 	scsi_host_get(us_to_host(us));
1030 	atomic_inc(&total_threads);
1031 	wake_up_process(th);
1032 
1033 	return 0;
1034 
1035 	/* We come here if there are any problems */
1036 BadDevice:
1037 	US_DEBUGP("storage_probe() failed\n");
1038 	release_everything(us);
1039 	return result;
1040 }
1041 
1042 /* Handle a disconnect event from the USB core */
1043 static void storage_disconnect(struct usb_interface *intf)
1044 {
1045 	struct us_data *us = usb_get_intfdata(intf);
1046 
1047 	US_DEBUGP("storage_disconnect() called\n");
1048 	quiesce_and_remove_host(us);
1049 	release_everything(us);
1050 }
1051 
1052 /***********************************************************************
1053  * Initialization and registration
1054  ***********************************************************************/
1055 
1056 static struct usb_driver usb_storage_driver = {
1057 	.name =		"usb-storage",
1058 	.probe =	storage_probe,
1059 	.disconnect =	storage_disconnect,
1060 #ifdef CONFIG_PM
1061 	.suspend =	storage_suspend,
1062 	.resume =	storage_resume,
1063 #endif
1064 	.pre_reset =	storage_pre_reset,
1065 	.post_reset =	storage_post_reset,
1066 	.id_table =	storage_usb_ids,
1067 };
1068 
1069 static int __init usb_stor_init(void)
1070 {
1071 	int retval;
1072 	printk(KERN_INFO "Initializing USB Mass Storage driver...\n");
1073 
1074 	/* register the driver, return usb_register return code if error */
1075 	retval = usb_register(&usb_storage_driver);
1076 	if (retval == 0) {
1077 		printk(KERN_INFO "USB Mass Storage support registered.\n");
1078 		usb_usual_set_present(USB_US_TYPE_STOR);
1079 	}
1080 	return retval;
1081 }
1082 
1083 static void __exit usb_stor_exit(void)
1084 {
1085 	US_DEBUGP("usb_stor_exit() called\n");
1086 
1087 	/* Deregister the driver
1088 	 * This will cause disconnect() to be called for each
1089 	 * attached unit
1090 	 */
1091 	US_DEBUGP("-- calling usb_deregister()\n");
1092 	usb_deregister(&usb_storage_driver) ;
1093 
1094 	/* Don't return until all of our control and scanning threads
1095 	 * have exited.  Since each thread signals threads_gone as its
1096 	 * last act, we have to call wait_for_completion the right number
1097 	 * of times.
1098 	 */
1099 	while (atomic_read(&total_threads) > 0) {
1100 		wait_for_completion(&threads_gone);
1101 		atomic_dec(&total_threads);
1102 	}
1103 
1104 	usb_usual_clear_present(USB_US_TYPE_STOR);
1105 }
1106 
1107 module_init(usb_stor_init);
1108 module_exit(usb_stor_exit);
1109