1 /* Driver for USB Mass Storage compliant devices
3 * $Id: usb.c,v 1.75 2002/04/22 03:39:43 mdharm Exp $
5 * Current development and maintenance by:
6 * (c) 1999-2003 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
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)
13 * (c) 1999 Michael Gee (michael@linuxspecific.com)
15 * usb_device_id support by Adam J. Richter (adam@yggdrasil.com):
16 * (c) 2000 Yggdrasil Computing, Inc.
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.
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.
29 * Also, for certain devices, the interrupt endpoint is used to convey
30 * status of a command.
32 * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
33 * information about this driver.
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
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.
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.
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 #include <linux/mutex.h>
60 #include <scsi/scsi.h>
61 #include <scsi/scsi_cmnd.h>
62 #include <scsi/scsi_device.h>
66 #include "transport.h"
69 #include "initializers.h"
71 #ifdef CONFIG_USB_STORAGE_USBAT
72 #include "shuttle_usbat.h"
74 #ifdef CONFIG_USB_STORAGE_SDDR09
77 #ifdef CONFIG_USB_STORAGE_SDDR55
80 #ifdef CONFIG_USB_STORAGE_DPCM
83 #ifdef CONFIG_USB_STORAGE_FREECOM
86 #ifdef CONFIG_USB_STORAGE_ISD200
89 #ifdef CONFIG_USB_STORAGE_DATAFAB
92 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
95 #ifdef CONFIG_USB_STORAGE_ONETOUCH
98 #ifdef CONFIG_USB_STORAGE_ALAUDA
102 /* Some informational data */
103 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
104 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
105 MODULE_LICENSE("GPL");
107 static unsigned int delay_use = 5;
108 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
109 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
112 /* These are used to make sure the module doesn't unload before all the
113 * threads have exited.
115 static atomic_t total_threads = ATOMIC_INIT(0);
116 static DECLARE_COMPLETION(threads_gone);
120 * The entries in this table correspond, line for line,
121 * with the entries of us_unusual_dev_list[].
123 #ifndef CONFIG_USB_LIBUSUAL
125 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
126 vendorName, productName,useProtocol, useTransport, \
127 initFunction, flags) \
128 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin,bcdDeviceMax), \
129 .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }
131 #define USUAL_DEV(useProto, useTrans, useType) \
132 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, useProto, useTrans), \
133 .driver_info = (USB_US_TYPE_STOR<<24) }
135 static struct usb_device_id storage_usb_ids [] = {
137 # include "unusual_devs.h"
140 /* Terminating entry */
144 MODULE_DEVICE_TABLE (usb, storage_usb_ids);
145 #endif /* CONFIG_USB_LIBUSUAL */
147 /* This is the list of devices we recognize, along with their flag data */
149 /* The vendor name should be kept at eight characters or less, and
150 * the product name should be kept at 16 characters or less. If a device
151 * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
152 * normally generated by a device thorugh the INQUIRY response will be
153 * taken from this list, and this is the reason for the above size
154 * restriction. However, if the flag is not present, then you
155 * are free to use as many characters as you like.
158 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
159 vendor_name, product_name, use_protocol, use_transport, \
160 init_function, Flags) \
162 .vendorName = vendor_name, \
163 .productName = product_name, \
164 .useProtocol = use_protocol, \
165 .useTransport = use_transport, \
166 .initFunction = init_function, \
169 #define USUAL_DEV(use_protocol, use_transport, use_type) \
171 .useProtocol = use_protocol, \
172 .useTransport = use_transport, \
175 static struct us_unusual_dev us_unusual_dev_list[] = {
176 # include "unusual_devs.h"
180 /* Terminating entry */
185 #ifdef CONFIG_PM /* Minimal support for suspend and resume */
187 static int storage_suspend(struct usb_interface *iface, pm_message_t message)
189 struct us_data *us = usb_get_intfdata(iface);
191 /* Wait until no command is running */
192 mutex_lock(&us->dev_mutex);
194 US_DEBUGP("%s\n", __FUNCTION__);
195 if (us->suspend_resume_hook)
196 (us->suspend_resume_hook)(us, US_SUSPEND);
197 iface->dev.power.power_state.event = message.event;
199 /* When runtime PM is working, we'll set a flag to indicate
200 * whether we should autoresume when a SCSI request arrives. */
202 mutex_unlock(&us->dev_mutex);
206 static int storage_resume(struct usb_interface *iface)
208 struct us_data *us = usb_get_intfdata(iface);
210 mutex_lock(&us->dev_mutex);
212 US_DEBUGP("%s\n", __FUNCTION__);
213 if (us->suspend_resume_hook)
214 (us->suspend_resume_hook)(us, US_RESUME);
215 iface->dev.power.power_state.event = PM_EVENT_ON;
217 mutex_unlock(&us->dev_mutex);
221 #endif /* CONFIG_PM */
224 * The next two routines get called just before and just after
225 * a USB port reset, whether from this driver or a different one.
228 static void storage_pre_reset(struct usb_interface *iface)
230 struct us_data *us = usb_get_intfdata(iface);
232 US_DEBUGP("%s\n", __FUNCTION__);
234 /* Make sure no command runs during the reset */
235 mutex_lock(&us->dev_mutex);
238 static void storage_post_reset(struct usb_interface *iface)
240 struct us_data *us = usb_get_intfdata(iface);
242 US_DEBUGP("%s\n", __FUNCTION__);
244 /* Report the reset to the SCSI core */
245 scsi_lock(us_to_host(us));
246 usb_stor_report_bus_reset(us);
247 scsi_unlock(us_to_host(us));
249 /* FIXME: Notify the subdrivers that they need to reinitialize
251 mutex_unlock(&us->dev_mutex);
255 * fill_inquiry_response takes an unsigned char array (which must
256 * be at least 36 characters) and populates the vendor name,
257 * product name, and revision fields. Then the array is copied
258 * into the SCSI command's response buffer (oddly enough
259 * called request_buffer). data_len contains the length of the
260 * data array, which again must be at least 36.
263 void fill_inquiry_response(struct us_data *us, unsigned char *data,
264 unsigned int data_len)
266 if (data_len<36) // You lose.
269 if(data[0]&0x20) { /* USB device currently not connected. Return
270 peripheral qualifier 001b ("...however, the
271 physical device is not currently connected
272 to this logical unit") and leave vendor and
273 product identification empty. ("If the target
274 does store some of the INQUIRY data on the
275 device, it may return zeros or ASCII spaces
276 (20h) in those fields until the data is
277 available from the device."). */
280 u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
281 memcpy(data+8, us->unusual_dev->vendorName,
282 strlen(us->unusual_dev->vendorName) > 8 ? 8 :
283 strlen(us->unusual_dev->vendorName));
284 memcpy(data+16, us->unusual_dev->productName,
285 strlen(us->unusual_dev->productName) > 16 ? 16 :
286 strlen(us->unusual_dev->productName));
287 data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
288 data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
289 data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
290 data[35] = 0x30 + ((bcdDevice) & 0x0F);
293 usb_stor_set_xfer_buf(data, data_len, us->srb);
296 static int usb_stor_control_thread(void * __us)
298 struct us_data *us = (struct us_data *)__us;
299 struct Scsi_Host *host = us_to_host(us);
301 current->flags |= PF_NOFREEZE;
304 US_DEBUGP("*** thread sleeping.\n");
305 if(down_interruptible(&us->sema))
308 US_DEBUGP("*** thread awakened.\n");
310 /* lock the device pointers */
311 mutex_lock(&(us->dev_mutex));
313 /* if the device has disconnected, we are free to exit */
314 if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
315 US_DEBUGP("-- exiting\n");
316 mutex_unlock(&us->dev_mutex);
320 /* lock access to the state */
323 /* has the command timed out *already* ? */
324 if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
325 us->srb->result = DID_ABORT << 16;
331 /* reject the command if the direction indicator
334 if (us->srb->sc_data_direction == DMA_BIDIRECTIONAL) {
335 US_DEBUGP("UNKNOWN data direction\n");
336 us->srb->result = DID_ERROR << 16;
339 /* reject if target != 0 or if LUN is higher than
340 * the maximum known LUN
342 else if (us->srb->device->id &&
343 !(us->flags & US_FL_SCM_MULT_TARG)) {
344 US_DEBUGP("Bad target number (%d:%d)\n",
345 us->srb->device->id, us->srb->device->lun);
346 us->srb->result = DID_BAD_TARGET << 16;
349 else if (us->srb->device->lun > us->max_lun) {
350 US_DEBUGP("Bad LUN (%d:%d)\n",
351 us->srb->device->id, us->srb->device->lun);
352 us->srb->result = DID_BAD_TARGET << 16;
355 /* Handle those devices which need us to fake
356 * their inquiry data */
357 else if ((us->srb->cmnd[0] == INQUIRY) &&
358 (us->flags & US_FL_FIX_INQUIRY)) {
359 unsigned char data_ptr[36] = {
360 0x00, 0x80, 0x02, 0x02,
361 0x1F, 0x00, 0x00, 0x00};
363 US_DEBUGP("Faking INQUIRY command\n");
364 fill_inquiry_response(us, data_ptr, 36);
365 us->srb->result = SAM_STAT_GOOD;
368 /* we've got a command, let's do it! */
370 US_DEBUG(usb_stor_show_command(us->srb));
371 us->proto_handler(us->srb, us);
374 /* lock access to the state */
377 /* indicate that the command is done */
378 if (us->srb->result != DID_ABORT << 16) {
379 US_DEBUGP("scsi cmd done, result=0x%x\n",
381 us->srb->scsi_done(us->srb);
384 US_DEBUGP("scsi command aborted\n");
387 /* If an abort request was received we need to signal that
388 * the abort has finished. The proper test for this is
389 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
390 * the timeout might have occurred after the command had
391 * already completed with a different result code. */
392 if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
393 complete(&(us->notify));
395 /* Allow USB transfers to resume */
396 clear_bit(US_FLIDX_ABORTING, &us->flags);
397 clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
400 /* finished working on this command */
404 /* unlock the device pointers */
405 mutex_unlock(&us->dev_mutex);
410 /* notify the exit routine that we're actually exiting now
412 * complete()/wait_for_completion() is similar to up()/down(),
413 * except that complete() is safe in the case where the structure
414 * is getting deleted in a parallel mode of execution (i.e. just
415 * after the down() -- that's necessary for the thread-shutdown
418 * complete_and_exit() goes even further than this -- it is safe in
419 * the case that the thread of the caller is going away (not just
420 * the structure) -- this is necessary for the module-remove case.
421 * This is important in preemption kernels, which transfer the flow
422 * of execution immediately upon a complete().
424 complete_and_exit(&threads_gone, 0);
427 /***********************************************************************
428 * Device probing and disconnecting
429 ***********************************************************************/
431 /* Associate our private data with the USB device */
432 static int associate_dev(struct us_data *us, struct usb_interface *intf)
434 US_DEBUGP("-- %s\n", __FUNCTION__);
436 /* Fill in the device-related fields */
437 us->pusb_dev = interface_to_usbdev(intf);
438 us->pusb_intf = intf;
439 us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
440 US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
441 le16_to_cpu(us->pusb_dev->descriptor.idVendor),
442 le16_to_cpu(us->pusb_dev->descriptor.idProduct),
443 le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
444 US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
445 intf->cur_altsetting->desc.bInterfaceSubClass,
446 intf->cur_altsetting->desc.bInterfaceProtocol);
448 /* Store our private data in the interface */
449 usb_set_intfdata(intf, us);
451 /* Allocate the device-related DMA-mapped buffers */
452 us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
453 GFP_KERNEL, &us->cr_dma);
455 US_DEBUGP("usb_ctrlrequest allocation failed\n");
459 us->iobuf = usb_buffer_alloc(us->pusb_dev, US_IOBUF_SIZE,
460 GFP_KERNEL, &us->iobuf_dma);
462 US_DEBUGP("I/O buffer allocation failed\n");
466 us->sensebuf = kmalloc(US_SENSE_SIZE, GFP_KERNEL);
468 US_DEBUGP("Sense buffer allocation failed\n");
474 /* Find an unusual_dev descriptor (always succeeds in the current code) */
475 static struct us_unusual_dev *find_unusual(const struct usb_device_id *id)
477 const int id_index = id - storage_usb_ids;
478 return &us_unusual_dev_list[id_index];
481 /* Get the unusual_devs entries and the string descriptors */
482 static void get_device_info(struct us_data *us, const struct usb_device_id *id)
484 struct usb_device *dev = us->pusb_dev;
485 struct usb_interface_descriptor *idesc =
486 &us->pusb_intf->cur_altsetting->desc;
487 struct us_unusual_dev *unusual_dev = find_unusual(id);
489 /* Store the entries */
490 us->unusual_dev = unusual_dev;
491 us->subclass = (unusual_dev->useProtocol == US_SC_DEVICE) ?
492 idesc->bInterfaceSubClass :
493 unusual_dev->useProtocol;
494 us->protocol = (unusual_dev->useTransport == US_PR_DEVICE) ?
495 idesc->bInterfaceProtocol :
496 unusual_dev->useTransport;
497 us->flags = USB_US_ORIG_FLAGS(id->driver_info);
500 * This flag is only needed when we're in high-speed, so let's
501 * disable it if we're in full-speed
503 if (dev->speed != USB_SPEED_HIGH)
504 us->flags &= ~US_FL_GO_SLOW;
506 /* Log a message if a non-generic unusual_dev entry contains an
507 * unnecessary subclass or protocol override. This may stimulate
508 * reports from users that will help us remove unneeded entries
509 * from the unusual_devs.h table.
511 if (id->idVendor || id->idProduct) {
512 static const char *msgs[3] = {
513 "an unneeded SubClass entry",
514 "an unneeded Protocol entry",
515 "unneeded SubClass and Protocol entries"};
516 struct usb_device_descriptor *ddesc = &dev->descriptor;
519 if (unusual_dev->useProtocol != US_SC_DEVICE &&
520 us->subclass == idesc->bInterfaceSubClass)
522 if (unusual_dev->useTransport != US_PR_DEVICE &&
523 us->protocol == idesc->bInterfaceProtocol)
525 if (msg >= 0 && !(us->flags & US_FL_NEED_OVERRIDE))
526 printk(KERN_NOTICE USB_STORAGE "This device "
527 "(%04x,%04x,%04x S %02x P %02x)"
528 " has %s in unusual_devs.h\n"
529 " Please send a copy of this message to "
530 "<linux-usb-devel@lists.sourceforge.net>\n",
531 le16_to_cpu(ddesc->idVendor),
532 le16_to_cpu(ddesc->idProduct),
533 le16_to_cpu(ddesc->bcdDevice),
534 idesc->bInterfaceSubClass,
535 idesc->bInterfaceProtocol,
540 /* Get the transport settings */
541 static int get_transport(struct us_data *us)
543 switch (us->protocol) {
545 us->transport_name = "Control/Bulk";
546 us->transport = usb_stor_CB_transport;
547 us->transport_reset = usb_stor_CB_reset;
552 us->transport_name = "Control/Bulk/Interrupt";
553 us->transport = usb_stor_CBI_transport;
554 us->transport_reset = usb_stor_CB_reset;
559 us->transport_name = "Bulk";
560 us->transport = usb_stor_Bulk_transport;
561 us->transport_reset = usb_stor_Bulk_reset;
564 #ifdef CONFIG_USB_STORAGE_USBAT
566 us->transport_name = "Shuttle USBAT";
567 us->transport = usbat_transport;
568 us->transport_reset = usb_stor_CB_reset;
573 #ifdef CONFIG_USB_STORAGE_SDDR09
574 case US_PR_EUSB_SDDR09:
575 us->transport_name = "EUSB/SDDR09";
576 us->transport = sddr09_transport;
577 us->transport_reset = usb_stor_CB_reset;
582 #ifdef CONFIG_USB_STORAGE_SDDR55
584 us->transport_name = "SDDR55";
585 us->transport = sddr55_transport;
586 us->transport_reset = sddr55_reset;
591 #ifdef CONFIG_USB_STORAGE_DPCM
593 us->transport_name = "Control/Bulk-EUSB/SDDR09";
594 us->transport = dpcm_transport;
595 us->transport_reset = usb_stor_CB_reset;
600 #ifdef CONFIG_USB_STORAGE_FREECOM
602 us->transport_name = "Freecom";
603 us->transport = freecom_transport;
604 us->transport_reset = usb_stor_freecom_reset;
609 #ifdef CONFIG_USB_STORAGE_DATAFAB
611 us->transport_name = "Datafab Bulk-Only";
612 us->transport = datafab_transport;
613 us->transport_reset = usb_stor_Bulk_reset;
618 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
620 us->transport_name = "Lexar Jumpshot Control/Bulk";
621 us->transport = jumpshot_transport;
622 us->transport_reset = usb_stor_Bulk_reset;
627 #ifdef CONFIG_USB_STORAGE_ALAUDA
629 us->transport_name = "Alauda Control/Bulk";
630 us->transport = alauda_transport;
631 us->transport_reset = usb_stor_Bulk_reset;
639 US_DEBUGP("Transport: %s\n", us->transport_name);
641 /* fix for single-lun devices */
642 if (us->flags & US_FL_SINGLE_LUN)
647 /* Get the protocol settings */
648 static int get_protocol(struct us_data *us)
650 switch (us->subclass) {
652 us->protocol_name = "Reduced Block Commands (RBC)";
653 us->proto_handler = usb_stor_transparent_scsi_command;
657 us->protocol_name = "8020i";
658 us->proto_handler = usb_stor_ATAPI_command;
663 us->protocol_name = "QIC-157";
664 us->proto_handler = usb_stor_qic157_command;
669 us->protocol_name = "8070i";
670 us->proto_handler = usb_stor_ATAPI_command;
675 us->protocol_name = "Transparent SCSI";
676 us->proto_handler = usb_stor_transparent_scsi_command;
680 us->protocol_name = "Uniform Floppy Interface (UFI)";
681 us->proto_handler = usb_stor_ufi_command;
684 #ifdef CONFIG_USB_STORAGE_ISD200
686 us->protocol_name = "ISD200 ATA/ATAPI";
687 us->proto_handler = isd200_ata_command;
694 US_DEBUGP("Protocol: %s\n", us->protocol_name);
698 /* Get the pipe settings */
699 static int get_pipes(struct us_data *us)
701 struct usb_host_interface *altsetting =
702 us->pusb_intf->cur_altsetting;
704 struct usb_endpoint_descriptor *ep;
705 struct usb_endpoint_descriptor *ep_in = NULL;
706 struct usb_endpoint_descriptor *ep_out = NULL;
707 struct usb_endpoint_descriptor *ep_int = NULL;
710 * Find the endpoints we need.
711 * We are expecting a minimum of 2 endpoints - in and out (bulk).
712 * An optional interrupt is OK (necessary for CBI protocol).
713 * We will ignore any others.
715 for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
716 ep = &altsetting->endpoint[i].desc;
718 /* Is it a BULK endpoint? */
719 if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
720 == USB_ENDPOINT_XFER_BULK) {
721 /* BULK in or out? */
722 if (ep->bEndpointAddress & USB_DIR_IN)
728 /* Is it an interrupt endpoint? */
729 else if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
730 == USB_ENDPOINT_XFER_INT) {
735 if (!ep_in || !ep_out || (us->protocol == US_PR_CBI && !ep_int)) {
736 US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
740 /* Calculate and store the pipe values */
741 us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
742 us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
743 us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
744 ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
745 us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
746 ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
748 us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
749 ep_int->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
750 us->ep_bInterval = ep_int->bInterval;
755 /* Initialize all the dynamic resources we need */
756 static int usb_stor_acquire_resources(struct us_data *us)
759 struct task_struct *th;
761 us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
762 if (!us->current_urb) {
763 US_DEBUGP("URB allocation failed\n");
767 /* Just before we start our control thread, initialize
768 * the device if it needs initialization */
769 if (us->unusual_dev->initFunction) {
770 p = us->unusual_dev->initFunction(us);
775 /* Start up our control thread */
776 th = kthread_create(usb_stor_control_thread, us, "usb-storage");
778 printk(KERN_WARNING USB_STORAGE
779 "Unable to start control thread\n");
783 /* Take a reference to the host for the control thread and
784 * count it among all the threads we have launched. Then
786 scsi_host_get(us_to_host(us));
787 atomic_inc(&total_threads);
793 /* Release all our dynamic resources */
794 static void usb_stor_release_resources(struct us_data *us)
796 US_DEBUGP("-- %s\n", __FUNCTION__);
798 /* Tell the control thread to exit. The SCSI host must
799 * already have been removed so it won't try to queue
802 US_DEBUGP("-- sending exit command to thread\n");
803 set_bit(US_FLIDX_DISCONNECTING, &us->flags);
806 /* Call the destructor routine, if it exists */
807 if (us->extra_destructor) {
808 US_DEBUGP("-- calling extra_destructor()\n");
809 us->extra_destructor(us->extra);
812 /* Free the extra data and the URB */
814 usb_free_urb(us->current_urb);
817 /* Dissociate from the USB device */
818 static void dissociate_dev(struct us_data *us)
820 US_DEBUGP("-- %s\n", __FUNCTION__);
824 /* Free the device-related DMA-mapped buffers */
826 usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
829 usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
832 /* Remove our private data from the interface */
833 usb_set_intfdata(us->pusb_intf, NULL);
836 /* First stage of disconnect processing: stop all commands and remove
838 static void quiesce_and_remove_host(struct us_data *us)
840 /* Prevent new USB transfers, stop the current command, and
841 * interrupt a SCSI-scan or device-reset delay */
842 set_bit(US_FLIDX_DISCONNECTING, &us->flags);
843 usb_stor_stop_transport(us);
844 wake_up(&us->delay_wait);
846 /* It doesn't matter if the SCSI-scanning thread is still running.
847 * The thread will exit when it sees the DISCONNECTING flag. */
849 /* Wait for the current command to finish, then remove the host */
850 mutex_lock(&us->dev_mutex);
851 mutex_unlock(&us->dev_mutex);
853 /* queuecommand won't accept any new commands and the control
854 * thread won't execute a previously-queued command. If there
855 * is such a command pending, complete it with an error. */
857 us->srb->result = DID_NO_CONNECT << 16;
858 scsi_lock(us_to_host(us));
859 us->srb->scsi_done(us->srb);
861 scsi_unlock(us_to_host(us));
864 /* Now we own no commands so it's safe to remove the SCSI host */
865 scsi_remove_host(us_to_host(us));
868 /* Second stage of disconnect processing: deallocate all resources */
869 static void release_everything(struct us_data *us)
871 usb_stor_release_resources(us);
874 /* Drop our reference to the host; the SCSI core will free it
875 * (and "us" along with it) when the refcount becomes 0. */
876 scsi_host_put(us_to_host(us));
879 /* Thread to carry out delayed SCSI-device scanning */
880 static int usb_stor_scan_thread(void * __us)
882 struct us_data *us = (struct us_data *)__us;
885 "usb-storage: device found at %d\n", us->pusb_dev->devnum);
887 /* Wait for the timeout to expire or for a disconnect */
889 printk(KERN_DEBUG "usb-storage: waiting for device "
890 "to settle before scanning\n");
892 wait_event_interruptible_timeout(us->delay_wait,
893 test_bit(US_FLIDX_DISCONNECTING, &us->flags),
899 /* If the device is still connected, perform the scanning */
900 if (!test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
902 /* For bulk-only devices, determine the max LUN value */
903 if (us->protocol == US_PR_BULK &&
904 !(us->flags & US_FL_SINGLE_LUN)) {
905 mutex_lock(&us->dev_mutex);
906 us->max_lun = usb_stor_Bulk_max_lun(us);
907 mutex_unlock(&us->dev_mutex);
909 scsi_scan_host(us_to_host(us));
910 printk(KERN_DEBUG "usb-storage: device scan complete\n");
912 /* Should we unbind if no devices were detected? */
915 scsi_host_put(us_to_host(us));
916 complete_and_exit(&threads_gone, 0);
920 /* Probe to see if we can drive a newly-connected USB device */
921 static int storage_probe(struct usb_interface *intf,
922 const struct usb_device_id *id)
924 struct Scsi_Host *host;
927 struct task_struct *th;
929 if (usb_usual_check_type(id, USB_US_TYPE_STOR))
932 US_DEBUGP("USB Mass Storage device detected\n");
935 * Ask the SCSI layer to allocate a host structure, with extra
936 * space at the end for our private us_data structure.
938 host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
940 printk(KERN_WARNING USB_STORAGE
941 "Unable to allocate the scsi host\n");
945 us = host_to_us(host);
946 memset(us, 0, sizeof(struct us_data));
947 mutex_init(&(us->dev_mutex));
948 init_MUTEX_LOCKED(&(us->sema));
949 init_completion(&(us->notify));
950 init_waitqueue_head(&us->delay_wait);
952 /* Associate the us_data structure with the USB device */
953 result = associate_dev(us, intf);
958 * Get the unusual_devs entries and the descriptors
960 * id_index is calculated in the declaration to be the index number
961 * of the match from the usb_device_id table, so we can find the
962 * corresponding entry in the private table.
964 get_device_info(us, id);
966 /* Get the transport, protocol, and pipe settings */
967 result = get_transport(us);
970 result = get_protocol(us);
973 result = get_pipes(us);
977 /* Acquire all the other resources and add the host */
978 result = usb_stor_acquire_resources(us);
981 result = scsi_add_host(host, &intf->dev);
983 printk(KERN_WARNING USB_STORAGE
984 "Unable to add the scsi host\n");
988 /* Start up the thread for delayed SCSI-device scanning */
989 th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
991 printk(KERN_WARNING USB_STORAGE
992 "Unable to start the device-scanning thread\n");
993 quiesce_and_remove_host(us);
994 result = PTR_ERR(th);
998 /* Take a reference to the host for the scanning thread and
999 * count it among all the threads we have launched. Then
1001 scsi_host_get(us_to_host(us));
1002 atomic_inc(&total_threads);
1003 wake_up_process(th);
1007 /* We come here if there are any problems */
1009 US_DEBUGP("storage_probe() failed\n");
1010 release_everything(us);
1014 /* Handle a disconnect event from the USB core */
1015 static void storage_disconnect(struct usb_interface *intf)
1017 struct us_data *us = usb_get_intfdata(intf);
1019 US_DEBUGP("storage_disconnect() called\n");
1020 quiesce_and_remove_host(us);
1021 release_everything(us);
1024 /***********************************************************************
1025 * Initialization and registration
1026 ***********************************************************************/
1028 static struct usb_driver usb_storage_driver = {
1029 .name = "usb-storage",
1030 .probe = storage_probe,
1031 .disconnect = storage_disconnect,
1033 .suspend = storage_suspend,
1034 .resume = storage_resume,
1036 .pre_reset = storage_pre_reset,
1037 .post_reset = storage_post_reset,
1038 .id_table = storage_usb_ids,
1041 static int __init usb_stor_init(void)
1044 printk(KERN_INFO "Initializing USB Mass Storage driver...\n");
1046 /* register the driver, return usb_register return code if error */
1047 retval = usb_register(&usb_storage_driver);
1049 printk(KERN_INFO "USB Mass Storage support registered.\n");
1050 usb_usual_set_present(USB_US_TYPE_STOR);
1055 static void __exit usb_stor_exit(void)
1057 US_DEBUGP("usb_stor_exit() called\n");
1059 /* Deregister the driver
1060 * This will cause disconnect() to be called for each
1063 US_DEBUGP("-- calling usb_deregister()\n");
1064 usb_deregister(&usb_storage_driver) ;
1066 /* Don't return until all of our control and scanning threads
1067 * have exited. Since each thread signals threads_gone as its
1068 * last act, we have to call wait_for_completion the right number
1071 while (atomic_read(&total_threads) > 0) {
1072 wait_for_completion(&threads_gone);
1073 atomic_dec(&total_threads);
1076 usb_usual_clear_present(USB_US_TYPE_STOR);
1079 module_init(usb_stor_init);
1080 module_exit(usb_stor_exit);