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/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>
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 /* did the command already complete because of a disconnect? */
379 ; /* nothing to do */
381 /* indicate that the command is done */
382 else if (us->srb->result != DID_ABORT << 16) {
383 US_DEBUGP("scsi cmd done, result=0x%x\n",
385 us->srb->scsi_done(us->srb);
388 US_DEBUGP("scsi command aborted\n");
391 /* If an abort request was received we need to signal that
392 * the abort has finished. The proper test for this is
393 * the TIMED_OUT flag, not srb->result == DID_ABORT, because
394 * the timeout might have occurred after the command had
395 * already completed with a different result code. */
396 if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
397 complete(&(us->notify));
399 /* Allow USB transfers to resume */
400 clear_bit(US_FLIDX_ABORTING, &us->flags);
401 clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
404 /* finished working on this command */
408 /* unlock the device pointers */
409 mutex_unlock(&us->dev_mutex);
414 /* notify the exit routine that we're actually exiting now
416 * complete()/wait_for_completion() is similar to up()/down(),
417 * except that complete() is safe in the case where the structure
418 * is getting deleted in a parallel mode of execution (i.e. just
419 * after the down() -- that's necessary for the thread-shutdown
422 * complete_and_exit() goes even further than this -- it is safe in
423 * the case that the thread of the caller is going away (not just
424 * the structure) -- this is necessary for the module-remove case.
425 * This is important in preemption kernels, which transfer the flow
426 * of execution immediately upon a complete().
428 complete_and_exit(&threads_gone, 0);
431 /***********************************************************************
432 * Device probing and disconnecting
433 ***********************************************************************/
435 /* Associate our private data with the USB device */
436 static int associate_dev(struct us_data *us, struct usb_interface *intf)
438 US_DEBUGP("-- %s\n", __FUNCTION__);
440 /* Fill in the device-related fields */
441 us->pusb_dev = interface_to_usbdev(intf);
442 us->pusb_intf = intf;
443 us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
444 US_DEBUGP("Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
445 le16_to_cpu(us->pusb_dev->descriptor.idVendor),
446 le16_to_cpu(us->pusb_dev->descriptor.idProduct),
447 le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
448 US_DEBUGP("Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
449 intf->cur_altsetting->desc.bInterfaceSubClass,
450 intf->cur_altsetting->desc.bInterfaceProtocol);
452 /* Store our private data in the interface */
453 usb_set_intfdata(intf, us);
455 /* Allocate the device-related DMA-mapped buffers */
456 us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
457 GFP_KERNEL, &us->cr_dma);
459 US_DEBUGP("usb_ctrlrequest allocation failed\n");
463 us->iobuf = usb_buffer_alloc(us->pusb_dev, US_IOBUF_SIZE,
464 GFP_KERNEL, &us->iobuf_dma);
466 US_DEBUGP("I/O buffer allocation failed\n");
470 us->sensebuf = kmalloc(US_SENSE_SIZE, GFP_KERNEL);
472 US_DEBUGP("Sense buffer allocation failed\n");
478 /* Find an unusual_dev descriptor (always succeeds in the current code) */
479 static struct us_unusual_dev *find_unusual(const struct usb_device_id *id)
481 const int id_index = id - storage_usb_ids;
482 return &us_unusual_dev_list[id_index];
485 /* Get the unusual_devs entries and the string descriptors */
486 static void get_device_info(struct us_data *us, const struct usb_device_id *id)
488 struct usb_device *dev = us->pusb_dev;
489 struct usb_interface_descriptor *idesc =
490 &us->pusb_intf->cur_altsetting->desc;
491 struct us_unusual_dev *unusual_dev = find_unusual(id);
493 /* Store the entries */
494 us->unusual_dev = unusual_dev;
495 us->subclass = (unusual_dev->useProtocol == US_SC_DEVICE) ?
496 idesc->bInterfaceSubClass :
497 unusual_dev->useProtocol;
498 us->protocol = (unusual_dev->useTransport == US_PR_DEVICE) ?
499 idesc->bInterfaceProtocol :
500 unusual_dev->useTransport;
501 us->flags = USB_US_ORIG_FLAGS(id->driver_info);
504 * This flag is only needed when we're in high-speed, so let's
505 * disable it if we're in full-speed
507 if (dev->speed != USB_SPEED_HIGH)
508 us->flags &= ~US_FL_GO_SLOW;
510 /* Log a message if a non-generic unusual_dev entry contains an
511 * unnecessary subclass or protocol override. This may stimulate
512 * reports from users that will help us remove unneeded entries
513 * from the unusual_devs.h table.
515 if (id->idVendor || id->idProduct) {
516 static const char *msgs[3] = {
517 "an unneeded SubClass entry",
518 "an unneeded Protocol entry",
519 "unneeded SubClass and Protocol entries"};
520 struct usb_device_descriptor *ddesc = &dev->descriptor;
523 if (unusual_dev->useProtocol != US_SC_DEVICE &&
524 us->subclass == idesc->bInterfaceSubClass)
526 if (unusual_dev->useTransport != US_PR_DEVICE &&
527 us->protocol == idesc->bInterfaceProtocol)
529 if (msg >= 0 && !(us->flags & US_FL_NEED_OVERRIDE))
530 printk(KERN_NOTICE USB_STORAGE "This device "
531 "(%04x,%04x,%04x S %02x P %02x)"
532 " has %s in unusual_devs.h (kernel"
534 " Please send a copy of this message to "
535 "<linux-usb-devel@lists.sourceforge.net>\n",
536 le16_to_cpu(ddesc->idVendor),
537 le16_to_cpu(ddesc->idProduct),
538 le16_to_cpu(ddesc->bcdDevice),
539 idesc->bInterfaceSubClass,
540 idesc->bInterfaceProtocol,
546 /* Get the transport settings */
547 static int get_transport(struct us_data *us)
549 switch (us->protocol) {
551 us->transport_name = "Control/Bulk";
552 us->transport = usb_stor_CB_transport;
553 us->transport_reset = usb_stor_CB_reset;
558 us->transport_name = "Control/Bulk/Interrupt";
559 us->transport = usb_stor_CBI_transport;
560 us->transport_reset = usb_stor_CB_reset;
565 us->transport_name = "Bulk";
566 us->transport = usb_stor_Bulk_transport;
567 us->transport_reset = usb_stor_Bulk_reset;
570 #ifdef CONFIG_USB_STORAGE_USBAT
572 us->transport_name = "Shuttle USBAT";
573 us->transport = usbat_transport;
574 us->transport_reset = usb_stor_CB_reset;
579 #ifdef CONFIG_USB_STORAGE_SDDR09
580 case US_PR_EUSB_SDDR09:
581 us->transport_name = "EUSB/SDDR09";
582 us->transport = sddr09_transport;
583 us->transport_reset = usb_stor_CB_reset;
588 #ifdef CONFIG_USB_STORAGE_SDDR55
590 us->transport_name = "SDDR55";
591 us->transport = sddr55_transport;
592 us->transport_reset = sddr55_reset;
597 #ifdef CONFIG_USB_STORAGE_DPCM
599 us->transport_name = "Control/Bulk-EUSB/SDDR09";
600 us->transport = dpcm_transport;
601 us->transport_reset = usb_stor_CB_reset;
606 #ifdef CONFIG_USB_STORAGE_FREECOM
608 us->transport_name = "Freecom";
609 us->transport = freecom_transport;
610 us->transport_reset = usb_stor_freecom_reset;
615 #ifdef CONFIG_USB_STORAGE_DATAFAB
617 us->transport_name = "Datafab Bulk-Only";
618 us->transport = datafab_transport;
619 us->transport_reset = usb_stor_Bulk_reset;
624 #ifdef CONFIG_USB_STORAGE_JUMPSHOT
626 us->transport_name = "Lexar Jumpshot Control/Bulk";
627 us->transport = jumpshot_transport;
628 us->transport_reset = usb_stor_Bulk_reset;
633 #ifdef CONFIG_USB_STORAGE_ALAUDA
635 us->transport_name = "Alauda Control/Bulk";
636 us->transport = alauda_transport;
637 us->transport_reset = usb_stor_Bulk_reset;
645 US_DEBUGP("Transport: %s\n", us->transport_name);
647 /* fix for single-lun devices */
648 if (us->flags & US_FL_SINGLE_LUN)
653 /* Get the protocol settings */
654 static int get_protocol(struct us_data *us)
656 switch (us->subclass) {
658 us->protocol_name = "Reduced Block Commands (RBC)";
659 us->proto_handler = usb_stor_transparent_scsi_command;
663 us->protocol_name = "8020i";
664 us->proto_handler = usb_stor_ATAPI_command;
669 us->protocol_name = "QIC-157";
670 us->proto_handler = usb_stor_qic157_command;
675 us->protocol_name = "8070i";
676 us->proto_handler = usb_stor_ATAPI_command;
681 us->protocol_name = "Transparent SCSI";
682 us->proto_handler = usb_stor_transparent_scsi_command;
686 us->protocol_name = "Uniform Floppy Interface (UFI)";
687 us->proto_handler = usb_stor_ufi_command;
690 #ifdef CONFIG_USB_STORAGE_ISD200
692 us->protocol_name = "ISD200 ATA/ATAPI";
693 us->proto_handler = isd200_ata_command;
700 US_DEBUGP("Protocol: %s\n", us->protocol_name);
704 /* Get the pipe settings */
705 static int get_pipes(struct us_data *us)
707 struct usb_host_interface *altsetting =
708 us->pusb_intf->cur_altsetting;
710 struct usb_endpoint_descriptor *ep;
711 struct usb_endpoint_descriptor *ep_in = NULL;
712 struct usb_endpoint_descriptor *ep_out = NULL;
713 struct usb_endpoint_descriptor *ep_int = NULL;
716 * Find the endpoints we need.
717 * We are expecting a minimum of 2 endpoints - in and out (bulk).
718 * An optional interrupt is OK (necessary for CBI protocol).
719 * We will ignore any others.
721 for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
722 ep = &altsetting->endpoint[i].desc;
724 /* Is it a BULK endpoint? */
725 if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
726 == USB_ENDPOINT_XFER_BULK) {
727 /* BULK in or out? */
728 if (ep->bEndpointAddress & USB_DIR_IN)
734 /* Is it an interrupt endpoint? */
735 else if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
736 == USB_ENDPOINT_XFER_INT) {
741 if (!ep_in || !ep_out || (us->protocol == US_PR_CBI && !ep_int)) {
742 US_DEBUGP("Endpoint sanity check failed! Rejecting dev.\n");
746 /* Calculate and store the pipe values */
747 us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
748 us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
749 us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
750 ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
751 us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
752 ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
754 us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
755 ep_int->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
756 us->ep_bInterval = ep_int->bInterval;
761 /* Initialize all the dynamic resources we need */
762 static int usb_stor_acquire_resources(struct us_data *us)
765 struct task_struct *th;
767 us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
768 if (!us->current_urb) {
769 US_DEBUGP("URB allocation failed\n");
773 /* Just before we start our control thread, initialize
774 * the device if it needs initialization */
775 if (us->unusual_dev->initFunction) {
776 p = us->unusual_dev->initFunction(us);
781 /* Start up our control thread */
782 th = kthread_create(usb_stor_control_thread, us, "usb-storage");
784 printk(KERN_WARNING USB_STORAGE
785 "Unable to start control thread\n");
789 /* Take a reference to the host for the control thread and
790 * count it among all the threads we have launched. Then
792 scsi_host_get(us_to_host(us));
793 atomic_inc(&total_threads);
799 /* Release all our dynamic resources */
800 static void usb_stor_release_resources(struct us_data *us)
802 US_DEBUGP("-- %s\n", __FUNCTION__);
804 /* Tell the control thread to exit. The SCSI host must
805 * already have been removed so it won't try to queue
808 US_DEBUGP("-- sending exit command to thread\n");
809 set_bit(US_FLIDX_DISCONNECTING, &us->flags);
812 /* Call the destructor routine, if it exists */
813 if (us->extra_destructor) {
814 US_DEBUGP("-- calling extra_destructor()\n");
815 us->extra_destructor(us->extra);
818 /* Free the extra data and the URB */
820 usb_free_urb(us->current_urb);
823 /* Dissociate from the USB device */
824 static void dissociate_dev(struct us_data *us)
826 US_DEBUGP("-- %s\n", __FUNCTION__);
830 /* Free the device-related DMA-mapped buffers */
832 usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
835 usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
838 /* Remove our private data from the interface */
839 usb_set_intfdata(us->pusb_intf, NULL);
842 /* First stage of disconnect processing: stop all commands and remove
844 static void quiesce_and_remove_host(struct us_data *us)
846 struct Scsi_Host *host = us_to_host(us);
848 /* Prevent new USB transfers, stop the current command, and
849 * interrupt a SCSI-scan or device-reset delay */
851 set_bit(US_FLIDX_DISCONNECTING, &us->flags);
853 usb_stor_stop_transport(us);
854 wake_up(&us->delay_wait);
856 /* It doesn't matter if the SCSI-scanning thread is still running.
857 * The thread will exit when it sees the DISCONNECTING flag. */
859 /* queuecommand won't accept any new commands and the control
860 * thread won't execute a previously-queued command. If there
861 * is such a command pending, complete it with an error. */
862 mutex_lock(&us->dev_mutex);
864 us->srb->result = DID_NO_CONNECT << 16;
866 us->srb->scsi_done(us->srb);
870 mutex_unlock(&us->dev_mutex);
872 /* Now we own no commands so it's safe to remove the SCSI host */
873 scsi_remove_host(host);
876 /* Second stage of disconnect processing: deallocate all resources */
877 static void release_everything(struct us_data *us)
879 usb_stor_release_resources(us);
882 /* Drop our reference to the host; the SCSI core will free it
883 * (and "us" along with it) when the refcount becomes 0. */
884 scsi_host_put(us_to_host(us));
887 /* Thread to carry out delayed SCSI-device scanning */
888 static int usb_stor_scan_thread(void * __us)
890 struct us_data *us = (struct us_data *)__us;
893 "usb-storage: device found at %d\n", us->pusb_dev->devnum);
895 /* Wait for the timeout to expire or for a disconnect */
897 printk(KERN_DEBUG "usb-storage: waiting for device "
898 "to settle before scanning\n");
900 wait_event_interruptible_timeout(us->delay_wait,
901 test_bit(US_FLIDX_DISCONNECTING, &us->flags),
907 /* If the device is still connected, perform the scanning */
908 if (!test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
910 /* For bulk-only devices, determine the max LUN value */
911 if (us->protocol == US_PR_BULK &&
912 !(us->flags & US_FL_SINGLE_LUN)) {
913 mutex_lock(&us->dev_mutex);
914 us->max_lun = usb_stor_Bulk_max_lun(us);
915 mutex_unlock(&us->dev_mutex);
917 scsi_scan_host(us_to_host(us));
918 printk(KERN_DEBUG "usb-storage: device scan complete\n");
920 /* Should we unbind if no devices were detected? */
923 scsi_host_put(us_to_host(us));
924 complete_and_exit(&threads_gone, 0);
928 /* Probe to see if we can drive a newly-connected USB device */
929 static int storage_probe(struct usb_interface *intf,
930 const struct usb_device_id *id)
932 struct Scsi_Host *host;
935 struct task_struct *th;
937 if (usb_usual_check_type(id, USB_US_TYPE_STOR))
940 US_DEBUGP("USB Mass Storage device detected\n");
943 * Ask the SCSI layer to allocate a host structure, with extra
944 * space at the end for our private us_data structure.
946 host = scsi_host_alloc(&usb_stor_host_template, sizeof(*us));
948 printk(KERN_WARNING USB_STORAGE
949 "Unable to allocate the scsi host\n");
953 us = host_to_us(host);
954 memset(us, 0, sizeof(struct us_data));
955 mutex_init(&(us->dev_mutex));
956 init_MUTEX_LOCKED(&(us->sema));
957 init_completion(&(us->notify));
958 init_waitqueue_head(&us->delay_wait);
960 /* Associate the us_data structure with the USB device */
961 result = associate_dev(us, intf);
966 * Get the unusual_devs entries and the descriptors
968 * id_index is calculated in the declaration to be the index number
969 * of the match from the usb_device_id table, so we can find the
970 * corresponding entry in the private table.
972 get_device_info(us, id);
974 /* Get the transport, protocol, and pipe settings */
975 result = get_transport(us);
978 result = get_protocol(us);
981 result = get_pipes(us);
985 /* Acquire all the other resources and add the host */
986 result = usb_stor_acquire_resources(us);
989 result = scsi_add_host(host, &intf->dev);
991 printk(KERN_WARNING USB_STORAGE
992 "Unable to add the scsi host\n");
996 /* Start up the thread for delayed SCSI-device scanning */
997 th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
999 printk(KERN_WARNING USB_STORAGE
1000 "Unable to start the device-scanning thread\n");
1001 quiesce_and_remove_host(us);
1002 result = PTR_ERR(th);
1006 /* Take a reference to the host for the scanning thread and
1007 * count it among all the threads we have launched. Then
1009 scsi_host_get(us_to_host(us));
1010 atomic_inc(&total_threads);
1011 wake_up_process(th);
1015 /* We come here if there are any problems */
1017 US_DEBUGP("storage_probe() failed\n");
1018 release_everything(us);
1022 /* Handle a disconnect event from the USB core */
1023 static void storage_disconnect(struct usb_interface *intf)
1025 struct us_data *us = usb_get_intfdata(intf);
1027 US_DEBUGP("storage_disconnect() called\n");
1028 quiesce_and_remove_host(us);
1029 release_everything(us);
1032 /***********************************************************************
1033 * Initialization and registration
1034 ***********************************************************************/
1036 static struct usb_driver usb_storage_driver = {
1037 .name = "usb-storage",
1038 .probe = storage_probe,
1039 .disconnect = storage_disconnect,
1041 .suspend = storage_suspend,
1042 .resume = storage_resume,
1044 .pre_reset = storage_pre_reset,
1045 .post_reset = storage_post_reset,
1046 .id_table = storage_usb_ids,
1049 static int __init usb_stor_init(void)
1052 printk(KERN_INFO "Initializing USB Mass Storage driver...\n");
1054 /* register the driver, return usb_register return code if error */
1055 retval = usb_register(&usb_storage_driver);
1057 printk(KERN_INFO "USB Mass Storage support registered.\n");
1058 usb_usual_set_present(USB_US_TYPE_STOR);
1063 static void __exit usb_stor_exit(void)
1065 US_DEBUGP("usb_stor_exit() called\n");
1067 /* Deregister the driver
1068 * This will cause disconnect() to be called for each
1071 US_DEBUGP("-- calling usb_deregister()\n");
1072 usb_deregister(&usb_storage_driver) ;
1074 /* Don't return until all of our control and scanning threads
1075 * have exited. Since each thread signals threads_gone as its
1076 * last act, we have to call wait_for_completion the right number
1079 while (atomic_read(&total_threads) > 0) {
1080 wait_for_completion(&threads_gone);
1081 atomic_dec(&total_threads);
1084 usb_usual_clear_present(USB_US_TYPE_STOR);
1087 module_init(usb_stor_init);
1088 module_exit(usb_stor_exit);