1 /* Driver for USB Mass Storage compliant devices
3 * $Id: transport.c,v 1.47 2002/04/22 03:39:43 mdharm Exp $
5 * Current development and maintenance by:
6 * (c) 1999-2002 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) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
11 * (c) 2002 Alan Stern <stern@rowland.org>
14 * (c) 1999 Michael Gee (michael@linuxspecific.com)
16 * This driver is based on the 'USB Mass Storage Class' document. This
17 * describes in detail the protocol used to communicate with such
18 * devices. Clearly, the designers had SCSI and ATAPI commands in
19 * mind when they created this document. The commands are all very
20 * similar to commands in the SCSI-II and ATAPI specifications.
22 * It is important to note that in a number of cases this class
23 * exhibits class-specific exemptions from the USB specification.
24 * Notably the usage of NAK, STALL and ACK differs from the norm, in
25 * that they are used to communicate wait, failed and OK on commands.
27 * Also, for certain devices, the interrupt endpoint is used to convey
28 * status of a command.
30 * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
31 * information about this driver.
33 * This program is free software; you can redistribute it and/or modify it
34 * under the terms of the GNU General Public License as published by the
35 * Free Software Foundation; either version 2, or (at your option) any
38 * This program is distributed in the hope that it will be useful, but
39 * WITHOUT ANY WARRANTY; without even the implied warranty of
40 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
41 * General Public License for more details.
43 * You should have received a copy of the GNU General Public License along
44 * with this program; if not, write to the Free Software Foundation, Inc.,
45 * 675 Mass Ave, Cambridge, MA 02139, USA.
48 #include <linux/sched.h>
49 #include <linux/errno.h>
50 #include <linux/slab.h>
52 #include <scsi/scsi.h>
53 #include <scsi/scsi_eh.h>
54 #include <scsi/scsi_device.h>
57 #include "transport.h"
63 /***********************************************************************
64 * Data transfer routines
65 ***********************************************************************/
68 * This is subtle, so pay attention:
69 * ---------------------------------
70 * We're very concerned about races with a command abort. Hanging this code
71 * is a sure fire way to hang the kernel. (Note that this discussion applies
72 * only to transactions resulting from a scsi queued-command, since only
73 * these transactions are subject to a scsi abort. Other transactions, such
74 * as those occurring during device-specific initialization, must be handled
75 * by a separate code path.)
77 * The abort function (usb_storage_command_abort() in scsiglue.c) first
78 * sets the machine state and the ABORTING bit in us->dflags to prevent
79 * new URBs from being submitted. It then calls usb_stor_stop_transport()
80 * below, which atomically tests-and-clears the URB_ACTIVE bit in us->dflags
81 * to see if the current_urb needs to be stopped. Likewise, the SG_ACTIVE
82 * bit is tested to see if the current_sg scatter-gather request needs to be
83 * stopped. The timeout callback routine does much the same thing.
85 * When a disconnect occurs, the DISCONNECTING bit in us->dflags is set to
86 * prevent new URBs from being submitted, and usb_stor_stop_transport() is
87 * called to stop any ongoing requests.
89 * The submit function first verifies that the submitting is allowed
90 * (neither ABORTING nor DISCONNECTING bits are set) and that the submit
91 * completes without errors, and only then sets the URB_ACTIVE bit. This
92 * prevents the stop_transport() function from trying to cancel the URB
93 * while the submit call is underway. Next, the submit function must test
94 * the flags to see if an abort or disconnect occurred during the submission
95 * or before the URB_ACTIVE bit was set. If so, it's essential to cancel
96 * the URB if it hasn't been cancelled already (i.e., if the URB_ACTIVE bit
97 * is still set). Either way, the function must then wait for the URB to
98 * finish. Note that the URB can still be in progress even after a call to
99 * usb_unlink_urb() returns.
101 * The idea is that (1) once the ABORTING or DISCONNECTING bit is set,
102 * either the stop_transport() function or the submitting function
103 * is guaranteed to call usb_unlink_urb() for an active URB,
104 * and (2) test_and_clear_bit() prevents usb_unlink_urb() from being
105 * called more than once or from being called during usb_submit_urb().
108 /* This is the completion handler which will wake us up when an URB
111 static void usb_stor_blocking_completion(struct urb
*urb
)
113 struct completion
*urb_done_ptr
= urb
->context
;
115 complete(urb_done_ptr
);
118 /* This is the common part of the URB message submission code
120 * All URBs from the usb-storage driver involved in handling a queued scsi
121 * command _must_ pass through this function (or something like it) for the
122 * abort mechanisms to work properly.
124 static int usb_stor_msg_common(struct us_data
*us
, int timeout
)
126 struct completion urb_done
;
130 /* don't submit URBs during abort processing */
131 if (test_bit(US_FLIDX_ABORTING
, &us
->dflags
))
134 /* set up data structures for the wakeup system */
135 init_completion(&urb_done
);
137 /* fill the common fields in the URB */
138 us
->current_urb
->context
= &urb_done
;
139 us
->current_urb
->actual_length
= 0;
140 us
->current_urb
->error_count
= 0;
141 us
->current_urb
->status
= 0;
143 /* we assume that if transfer_buffer isn't us->iobuf then it
144 * hasn't been mapped for DMA. Yes, this is clunky, but it's
145 * easier than always having the caller tell us whether the
146 * transfer buffer has already been mapped. */
147 us
->current_urb
->transfer_flags
= URB_NO_SETUP_DMA_MAP
;
148 if (us
->current_urb
->transfer_buffer
== us
->iobuf
)
149 us
->current_urb
->transfer_flags
|= URB_NO_TRANSFER_DMA_MAP
;
150 us
->current_urb
->transfer_dma
= us
->iobuf_dma
;
151 us
->current_urb
->setup_dma
= us
->cr_dma
;
154 status
= usb_submit_urb(us
->current_urb
, GFP_NOIO
);
156 /* something went wrong */
160 /* since the URB has been submitted successfully, it's now okay
162 set_bit(US_FLIDX_URB_ACTIVE
, &us
->dflags
);
164 /* did an abort occur during the submission? */
165 if (test_bit(US_FLIDX_ABORTING
, &us
->dflags
)) {
167 /* cancel the URB, if it hasn't been cancelled already */
168 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE
, &us
->dflags
)) {
169 US_DEBUGP("-- cancelling URB\n");
170 usb_unlink_urb(us
->current_urb
);
174 /* wait for the completion of the URB */
175 timeleft
= wait_for_completion_interruptible_timeout(
176 &urb_done
, timeout
? : MAX_SCHEDULE_TIMEOUT
);
178 clear_bit(US_FLIDX_URB_ACTIVE
, &us
->dflags
);
181 US_DEBUGP("%s -- cancelling URB\n",
182 timeleft
== 0 ? "Timeout" : "Signal");
183 usb_kill_urb(us
->current_urb
);
186 /* return the URB status */
187 return us
->current_urb
->status
;
191 * Transfer one control message, with timeouts, and allowing early
192 * termination. Return codes are usual -Exxx, *not* USB_STOR_XFER_xxx.
194 int usb_stor_control_msg(struct us_data
*us
, unsigned int pipe
,
195 u8 request
, u8 requesttype
, u16 value
, u16 index
,
196 void *data
, u16 size
, int timeout
)
200 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
201 __func__
, request
, requesttype
,
204 /* fill in the devrequest structure */
205 us
->cr
->bRequestType
= requesttype
;
206 us
->cr
->bRequest
= request
;
207 us
->cr
->wValue
= cpu_to_le16(value
);
208 us
->cr
->wIndex
= cpu_to_le16(index
);
209 us
->cr
->wLength
= cpu_to_le16(size
);
211 /* fill and submit the URB */
212 usb_fill_control_urb(us
->current_urb
, us
->pusb_dev
, pipe
,
213 (unsigned char*) us
->cr
, data
, size
,
214 usb_stor_blocking_completion
, NULL
);
215 status
= usb_stor_msg_common(us
, timeout
);
217 /* return the actual length of the data transferred if no error */
219 status
= us
->current_urb
->actual_length
;
223 /* This is a version of usb_clear_halt() that allows early termination and
224 * doesn't read the status from the device -- this is because some devices
225 * crash their internal firmware when the status is requested after a halt.
227 * A definitive list of these 'bad' devices is too difficult to maintain or
228 * make complete enough to be useful. This problem was first observed on the
229 * Hagiwara FlashGate DUAL unit. However, bus traces reveal that neither
230 * MacOS nor Windows checks the status after clearing a halt.
232 * Since many vendors in this space limit their testing to interoperability
233 * with these two OSes, specification violations like this one are common.
235 int usb_stor_clear_halt(struct us_data
*us
, unsigned int pipe
)
238 int endp
= usb_pipeendpoint(pipe
);
240 if (usb_pipein (pipe
))
243 result
= usb_stor_control_msg(us
, us
->send_ctrl_pipe
,
244 USB_REQ_CLEAR_FEATURE
, USB_RECIP_ENDPOINT
,
245 USB_ENDPOINT_HALT
, endp
,
248 /* reset the endpoint toggle */
250 usb_settoggle(us
->pusb_dev
, usb_pipeendpoint(pipe
),
251 usb_pipeout(pipe
), 0);
253 US_DEBUGP("%s: result = %d\n", __func__
, result
);
259 * Interpret the results of a URB transfer
261 * This function prints appropriate debugging messages, clears halts on
262 * non-control endpoints, and translates the status to the corresponding
263 * USB_STOR_XFER_xxx return code.
265 static int interpret_urb_result(struct us_data
*us
, unsigned int pipe
,
266 unsigned int length
, int result
, unsigned int partial
)
268 US_DEBUGP("Status code %d; transferred %u/%u\n",
269 result
, partial
, length
);
272 /* no error code; did we send all the data? */
274 if (partial
!= length
) {
275 US_DEBUGP("-- short transfer\n");
276 return USB_STOR_XFER_SHORT
;
279 US_DEBUGP("-- transfer complete\n");
280 return USB_STOR_XFER_GOOD
;
284 /* for control endpoints, (used by CB[I]) a stall indicates
285 * a failed command */
286 if (usb_pipecontrol(pipe
)) {
287 US_DEBUGP("-- stall on control pipe\n");
288 return USB_STOR_XFER_STALLED
;
291 /* for other sorts of endpoint, clear the stall */
292 US_DEBUGP("clearing endpoint halt for pipe 0x%x\n", pipe
);
293 if (usb_stor_clear_halt(us
, pipe
) < 0)
294 return USB_STOR_XFER_ERROR
;
295 return USB_STOR_XFER_STALLED
;
297 /* babble - the device tried to send more than we wanted to read */
299 US_DEBUGP("-- babble\n");
300 return USB_STOR_XFER_LONG
;
302 /* the transfer was cancelled by abort, disconnect, or timeout */
304 US_DEBUGP("-- transfer cancelled\n");
305 return USB_STOR_XFER_ERROR
;
307 /* short scatter-gather read transfer */
309 US_DEBUGP("-- short read transfer\n");
310 return USB_STOR_XFER_SHORT
;
312 /* abort or disconnect in progress */
314 US_DEBUGP("-- abort or disconnect in progress\n");
315 return USB_STOR_XFER_ERROR
;
317 /* the catch-all error case */
319 US_DEBUGP("-- unknown error\n");
320 return USB_STOR_XFER_ERROR
;
325 * Transfer one control message, without timeouts, but allowing early
326 * termination. Return codes are USB_STOR_XFER_xxx.
328 int usb_stor_ctrl_transfer(struct us_data
*us
, unsigned int pipe
,
329 u8 request
, u8 requesttype
, u16 value
, u16 index
,
330 void *data
, u16 size
)
334 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
335 __func__
, request
, requesttype
,
338 /* fill in the devrequest structure */
339 us
->cr
->bRequestType
= requesttype
;
340 us
->cr
->bRequest
= request
;
341 us
->cr
->wValue
= cpu_to_le16(value
);
342 us
->cr
->wIndex
= cpu_to_le16(index
);
343 us
->cr
->wLength
= cpu_to_le16(size
);
345 /* fill and submit the URB */
346 usb_fill_control_urb(us
->current_urb
, us
->pusb_dev
, pipe
,
347 (unsigned char*) us
->cr
, data
, size
,
348 usb_stor_blocking_completion
, NULL
);
349 result
= usb_stor_msg_common(us
, 0);
351 return interpret_urb_result(us
, pipe
, size
, result
,
352 us
->current_urb
->actual_length
);
356 * Receive one interrupt buffer, without timeouts, but allowing early
357 * termination. Return codes are USB_STOR_XFER_xxx.
359 * This routine always uses us->recv_intr_pipe as the pipe and
360 * us->ep_bInterval as the interrupt interval.
362 static int usb_stor_intr_transfer(struct us_data
*us
, void *buf
,
366 unsigned int pipe
= us
->recv_intr_pipe
;
369 US_DEBUGP("%s: xfer %u bytes\n", __func__
, length
);
371 /* calculate the max packet size */
372 maxp
= usb_maxpacket(us
->pusb_dev
, pipe
, usb_pipeout(pipe
));
376 /* fill and submit the URB */
377 usb_fill_int_urb(us
->current_urb
, us
->pusb_dev
, pipe
, buf
,
378 maxp
, usb_stor_blocking_completion
, NULL
,
380 result
= usb_stor_msg_common(us
, 0);
382 return interpret_urb_result(us
, pipe
, length
, result
,
383 us
->current_urb
->actual_length
);
387 * Transfer one buffer via bulk pipe, without timeouts, but allowing early
388 * termination. Return codes are USB_STOR_XFER_xxx. If the bulk pipe
389 * stalls during the transfer, the halt is automatically cleared.
391 int usb_stor_bulk_transfer_buf(struct us_data
*us
, unsigned int pipe
,
392 void *buf
, unsigned int length
, unsigned int *act_len
)
396 US_DEBUGP("%s: xfer %u bytes\n", __func__
, length
);
398 /* fill and submit the URB */
399 usb_fill_bulk_urb(us
->current_urb
, us
->pusb_dev
, pipe
, buf
, length
,
400 usb_stor_blocking_completion
, NULL
);
401 result
= usb_stor_msg_common(us
, 0);
403 /* store the actual length of the data transferred */
405 *act_len
= us
->current_urb
->actual_length
;
406 return interpret_urb_result(us
, pipe
, length
, result
,
407 us
->current_urb
->actual_length
);
411 * Transfer a scatter-gather list via bulk transfer
413 * This function does basically the same thing as usb_stor_bulk_transfer_buf()
414 * above, but it uses the usbcore scatter-gather library.
416 static int usb_stor_bulk_transfer_sglist(struct us_data
*us
, unsigned int pipe
,
417 struct scatterlist
*sg
, int num_sg
, unsigned int length
,
418 unsigned int *act_len
)
422 /* don't submit s-g requests during abort processing */
423 if (test_bit(US_FLIDX_ABORTING
, &us
->dflags
))
424 return USB_STOR_XFER_ERROR
;
426 /* initialize the scatter-gather request block */
427 US_DEBUGP("%s: xfer %u bytes, %d entries\n", __func__
,
429 result
= usb_sg_init(&us
->current_sg
, us
->pusb_dev
, pipe
, 0,
430 sg
, num_sg
, length
, GFP_NOIO
);
432 US_DEBUGP("usb_sg_init returned %d\n", result
);
433 return USB_STOR_XFER_ERROR
;
436 /* since the block has been initialized successfully, it's now
437 * okay to cancel it */
438 set_bit(US_FLIDX_SG_ACTIVE
, &us
->dflags
);
440 /* did an abort occur during the submission? */
441 if (test_bit(US_FLIDX_ABORTING
, &us
->dflags
)) {
443 /* cancel the request, if it hasn't been cancelled already */
444 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE
, &us
->dflags
)) {
445 US_DEBUGP("-- cancelling sg request\n");
446 usb_sg_cancel(&us
->current_sg
);
450 /* wait for the completion of the transfer */
451 usb_sg_wait(&us
->current_sg
);
452 clear_bit(US_FLIDX_SG_ACTIVE
, &us
->dflags
);
454 result
= us
->current_sg
.status
;
456 *act_len
= us
->current_sg
.bytes
;
457 return interpret_urb_result(us
, pipe
, length
, result
,
458 us
->current_sg
.bytes
);
462 * Common used function. Transfer a complete command
463 * via usb_stor_bulk_transfer_sglist() above. Set cmnd resid
465 int usb_stor_bulk_srb(struct us_data
* us
, unsigned int pipe
,
466 struct scsi_cmnd
* srb
)
468 unsigned int partial
;
469 int result
= usb_stor_bulk_transfer_sglist(us
, pipe
, scsi_sglist(srb
),
470 scsi_sg_count(srb
), scsi_bufflen(srb
),
473 scsi_set_resid(srb
, scsi_bufflen(srb
) - partial
);
478 * Transfer an entire SCSI command's worth of data payload over the bulk
481 * Note that this uses usb_stor_bulk_transfer_buf() and
482 * usb_stor_bulk_transfer_sglist() to achieve its goals --
483 * this function simply determines whether we're going to use
484 * scatter-gather or not, and acts appropriately.
486 int usb_stor_bulk_transfer_sg(struct us_data
* us
, unsigned int pipe
,
487 void *buf
, unsigned int length_left
, int use_sg
, int *residual
)
490 unsigned int partial
;
492 /* are we scatter-gathering? */
494 /* use the usb core scatter-gather primitives */
495 result
= usb_stor_bulk_transfer_sglist(us
, pipe
,
496 (struct scatterlist
*) buf
, use_sg
,
497 length_left
, &partial
);
498 length_left
-= partial
;
500 /* no scatter-gather, just make the request */
501 result
= usb_stor_bulk_transfer_buf(us
, pipe
, buf
,
502 length_left
, &partial
);
503 length_left
-= partial
;
506 /* store the residual and return the error code */
508 *residual
= length_left
;
512 /***********************************************************************
514 ***********************************************************************/
516 /* Invoke the transport and basic error-handling/recovery methods
518 * This is used by the protocol layers to actually send the message to
519 * the device and receive the response.
521 void usb_stor_invoke_transport(struct scsi_cmnd
*srb
, struct us_data
*us
)
526 /* send the command to the transport layer */
527 scsi_set_resid(srb
, 0);
528 result
= us
->transport(srb
, us
);
530 /* if the command gets aborted by the higher layers, we need to
531 * short-circuit all other processing
533 if (test_bit(US_FLIDX_TIMED_OUT
, &us
->dflags
)) {
534 US_DEBUGP("-- command was aborted\n");
535 srb
->result
= DID_ABORT
<< 16;
539 /* if there is a transport error, reset and don't auto-sense */
540 if (result
== USB_STOR_TRANSPORT_ERROR
) {
541 US_DEBUGP("-- transport indicates error, resetting\n");
542 srb
->result
= DID_ERROR
<< 16;
546 /* if the transport provided its own sense data, don't auto-sense */
547 if (result
== USB_STOR_TRANSPORT_NO_SENSE
) {
548 srb
->result
= SAM_STAT_CHECK_CONDITION
;
552 srb
->result
= SAM_STAT_GOOD
;
554 /* Determine if we need to auto-sense
556 * I normally don't use a flag like this, but it's almost impossible
557 * to understand what's going on here if I don't.
562 * If we're running the CB transport, which is incapable
563 * of determining status on its own, we will auto-sense
564 * unless the operation involved a data-in transfer. Devices
565 * can signal most data-in errors by stalling the bulk-in pipe.
567 if ((us
->protocol
== US_PR_CB
|| us
->protocol
== US_PR_DPCM_USB
) &&
568 srb
->sc_data_direction
!= DMA_FROM_DEVICE
) {
569 US_DEBUGP("-- CB transport device requiring auto-sense\n");
574 * If we have a failure, we're going to do a REQUEST_SENSE
575 * automatically. Note that we differentiate between a command
576 * "failure" and an "error" in the transport mechanism.
578 if (result
== USB_STOR_TRANSPORT_FAILED
) {
579 US_DEBUGP("-- transport indicates command failure\n");
584 * A short transfer on a command where we don't expect it
585 * is unusual, but it doesn't mean we need to auto-sense.
587 if ((scsi_get_resid(srb
) > 0) &&
588 !((srb
->cmnd
[0] == REQUEST_SENSE
) ||
589 (srb
->cmnd
[0] == INQUIRY
) ||
590 (srb
->cmnd
[0] == MODE_SENSE
) ||
591 (srb
->cmnd
[0] == LOG_SENSE
) ||
592 (srb
->cmnd
[0] == MODE_SENSE_10
))) {
593 US_DEBUGP("-- unexpectedly short transfer\n");
596 /* Now, if we need to do the auto-sense, let's do it */
597 if (need_auto_sense
) {
599 struct scsi_eh_save ses
;
601 US_DEBUGP("Issuing auto-REQUEST_SENSE\n");
603 scsi_eh_prep_cmnd(srb
, &ses
, NULL
, 0, US_SENSE_SIZE
);
605 /* FIXME: we must do the protocol translation here */
606 if (us
->subclass
== US_SC_RBC
|| us
->subclass
== US_SC_SCSI
||
607 us
->subclass
== US_SC_CYP_ATACB
)
612 /* issue the auto-sense command */
613 scsi_set_resid(srb
, 0);
614 temp_result
= us
->transport(us
->srb
, us
);
616 /* let's clean up right away */
617 scsi_eh_restore_cmnd(srb
, &ses
);
619 if (test_bit(US_FLIDX_TIMED_OUT
, &us
->dflags
)) {
620 US_DEBUGP("-- auto-sense aborted\n");
621 srb
->result
= DID_ABORT
<< 16;
624 if (temp_result
!= USB_STOR_TRANSPORT_GOOD
) {
625 US_DEBUGP("-- auto-sense failure\n");
627 /* we skip the reset if this happens to be a
628 * multi-target device, since failure of an
629 * auto-sense is perfectly valid
631 srb
->result
= DID_ERROR
<< 16;
632 if (!(us
->fflags
& US_FL_SCM_MULT_TARG
))
637 US_DEBUGP("-- Result from auto-sense is %d\n", temp_result
);
638 US_DEBUGP("-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n",
639 srb
->sense_buffer
[0],
640 srb
->sense_buffer
[2] & 0xf,
641 srb
->sense_buffer
[12],
642 srb
->sense_buffer
[13]);
643 #ifdef CONFIG_USB_STORAGE_DEBUG
645 srb
->sense_buffer
[2] & 0xf,
646 srb
->sense_buffer
[12],
647 srb
->sense_buffer
[13]);
650 /* set the result so the higher layers expect this data */
651 srb
->result
= SAM_STAT_CHECK_CONDITION
;
653 /* If things are really okay, then let's show that. Zero
654 * out the sense buffer so the higher layers won't realize
655 * we did an unsolicited auto-sense. */
656 if (result
== USB_STOR_TRANSPORT_GOOD
&&
657 /* Filemark 0, ignore EOM, ILI 0, no sense */
658 (srb
->sense_buffer
[2] & 0xaf) == 0 &&
660 srb
->sense_buffer
[12] == 0 &&
661 srb
->sense_buffer
[13] == 0) {
662 srb
->result
= SAM_STAT_GOOD
;
663 srb
->sense_buffer
[0] = 0x0;
667 /* Did we transfer less than the minimum amount required? */
668 if (srb
->result
== SAM_STAT_GOOD
&&
669 scsi_bufflen(srb
) - scsi_get_resid(srb
) < srb
->underflow
)
670 srb
->result
= (DID_ERROR
<< 16) | (SUGGEST_RETRY
<< 24);
674 /* Error and abort processing: try to resynchronize with the device
675 * by issuing a port reset. If that fails, try a class-specific
679 /* Set the RESETTING bit, and clear the ABORTING bit so that
680 * the reset may proceed. */
681 scsi_lock(us_to_host(us
));
682 set_bit(US_FLIDX_RESETTING
, &us
->dflags
);
683 clear_bit(US_FLIDX_ABORTING
, &us
->dflags
);
684 scsi_unlock(us_to_host(us
));
686 /* We must release the device lock because the pre_reset routine
687 * will want to acquire it. */
688 mutex_unlock(&us
->dev_mutex
);
689 result
= usb_stor_port_reset(us
);
690 mutex_lock(&us
->dev_mutex
);
693 scsi_lock(us_to_host(us
));
694 usb_stor_report_device_reset(us
);
695 scsi_unlock(us_to_host(us
));
696 us
->transport_reset(us
);
698 clear_bit(US_FLIDX_RESETTING
, &us
->dflags
);
701 /* Stop the current URB transfer */
702 void usb_stor_stop_transport(struct us_data
*us
)
704 US_DEBUGP("%s called\n", __func__
);
706 /* If the state machine is blocked waiting for an URB,
707 * let's wake it up. The test_and_clear_bit() call
708 * guarantees that if a URB has just been submitted,
709 * it won't be cancelled more than once. */
710 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE
, &us
->dflags
)) {
711 US_DEBUGP("-- cancelling URB\n");
712 usb_unlink_urb(us
->current_urb
);
715 /* If we are waiting for a scatter-gather operation, cancel it. */
716 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE
, &us
->dflags
)) {
717 US_DEBUGP("-- cancelling sg request\n");
718 usb_sg_cancel(&us
->current_sg
);
723 * Control/Bulk/Interrupt transport
726 int usb_stor_CBI_transport(struct scsi_cmnd
*srb
, struct us_data
*us
)
728 unsigned int transfer_length
= scsi_bufflen(srb
);
729 unsigned int pipe
= 0;
733 /* let's send the command via the control pipe */
734 result
= usb_stor_ctrl_transfer(us
, us
->send_ctrl_pipe
,
736 USB_TYPE_CLASS
| USB_RECIP_INTERFACE
, 0,
737 us
->ifnum
, srb
->cmnd
, srb
->cmd_len
);
739 /* check the return code for the command */
740 US_DEBUGP("Call to usb_stor_ctrl_transfer() returned %d\n", result
);
742 /* if we stalled the command, it means command failed */
743 if (result
== USB_STOR_XFER_STALLED
) {
744 return USB_STOR_TRANSPORT_FAILED
;
747 /* Uh oh... serious problem here */
748 if (result
!= USB_STOR_XFER_GOOD
) {
749 return USB_STOR_TRANSPORT_ERROR
;
753 /* transfer the data payload for this command, if one exists*/
754 if (transfer_length
) {
755 pipe
= srb
->sc_data_direction
== DMA_FROM_DEVICE
?
756 us
->recv_bulk_pipe
: us
->send_bulk_pipe
;
757 result
= usb_stor_bulk_srb(us
, pipe
, srb
);
758 US_DEBUGP("CBI data stage result is 0x%x\n", result
);
760 /* if we stalled the data transfer it means command failed */
761 if (result
== USB_STOR_XFER_STALLED
)
762 return USB_STOR_TRANSPORT_FAILED
;
763 if (result
> USB_STOR_XFER_STALLED
)
764 return USB_STOR_TRANSPORT_ERROR
;
768 result
= usb_stor_intr_transfer(us
, us
->iobuf
, 2);
769 US_DEBUGP("Got interrupt data (0x%x, 0x%x)\n",
770 us
->iobuf
[0], us
->iobuf
[1]);
771 if (result
!= USB_STOR_XFER_GOOD
)
772 return USB_STOR_TRANSPORT_ERROR
;
774 /* UFI gives us ASC and ASCQ, like a request sense
776 * REQUEST_SENSE and INQUIRY don't affect the sense data on UFI
777 * devices, so we ignore the information for those commands. Note
778 * that this means we could be ignoring a real error on these
779 * commands, but that can't be helped.
781 if (us
->subclass
== US_SC_UFI
) {
782 if (srb
->cmnd
[0] == REQUEST_SENSE
||
783 srb
->cmnd
[0] == INQUIRY
)
784 return USB_STOR_TRANSPORT_GOOD
;
787 return USB_STOR_TRANSPORT_GOOD
;
790 /* If not UFI, we interpret the data as a result code
791 * The first byte should always be a 0x0.
793 * Some bogus devices don't follow that rule. They stuff the ASC
794 * into the first byte -- so if it's non-zero, call it a failure.
797 US_DEBUGP("CBI IRQ data showed reserved bType 0x%x\n",
803 /* The second byte & 0x0F should be 0x0 for good, otherwise error */
804 switch (us
->iobuf
[1] & 0x0F) {
806 return USB_STOR_TRANSPORT_GOOD
;
810 return USB_STOR_TRANSPORT_ERROR
;
812 /* the CBI spec requires that the bulk pipe must be cleared
813 * following any data-in/out command failure (section 2.4.3.1.3)
817 usb_stor_clear_halt(us
, pipe
);
818 return USB_STOR_TRANSPORT_FAILED
;
822 * Control/Bulk transport
824 int usb_stor_CB_transport(struct scsi_cmnd
*srb
, struct us_data
*us
)
826 unsigned int transfer_length
= scsi_bufflen(srb
);
830 /* let's send the command via the control pipe */
831 result
= usb_stor_ctrl_transfer(us
, us
->send_ctrl_pipe
,
833 USB_TYPE_CLASS
| USB_RECIP_INTERFACE
, 0,
834 us
->ifnum
, srb
->cmnd
, srb
->cmd_len
);
836 /* check the return code for the command */
837 US_DEBUGP("Call to usb_stor_ctrl_transfer() returned %d\n", result
);
839 /* if we stalled the command, it means command failed */
840 if (result
== USB_STOR_XFER_STALLED
) {
841 return USB_STOR_TRANSPORT_FAILED
;
844 /* Uh oh... serious problem here */
845 if (result
!= USB_STOR_XFER_GOOD
) {
846 return USB_STOR_TRANSPORT_ERROR
;
850 /* transfer the data payload for this command, if one exists*/
851 if (transfer_length
) {
852 unsigned int pipe
= srb
->sc_data_direction
== DMA_FROM_DEVICE
?
853 us
->recv_bulk_pipe
: us
->send_bulk_pipe
;
854 result
= usb_stor_bulk_srb(us
, pipe
, srb
);
855 US_DEBUGP("CB data stage result is 0x%x\n", result
);
857 /* if we stalled the data transfer it means command failed */
858 if (result
== USB_STOR_XFER_STALLED
)
859 return USB_STOR_TRANSPORT_FAILED
;
860 if (result
> USB_STOR_XFER_STALLED
)
861 return USB_STOR_TRANSPORT_ERROR
;
865 /* NOTE: CB does not have a status stage. Silly, I know. So
866 * we have to catch this at a higher level.
868 return USB_STOR_TRANSPORT_GOOD
;
872 * Bulk only transport
875 /* Determine what the maximum LUN supported is */
876 int usb_stor_Bulk_max_lun(struct us_data
*us
)
880 /* issue the command */
882 result
= usb_stor_control_msg(us
, us
->recv_ctrl_pipe
,
884 USB_DIR_IN
| USB_TYPE_CLASS
|
886 0, us
->ifnum
, us
->iobuf
, 1, HZ
);
888 US_DEBUGP("GetMaxLUN command result is %d, data is %d\n",
889 result
, us
->iobuf
[0]);
891 /* if we have a successful request, return the result */
896 * Some devices don't like GetMaxLUN. They may STALL the control
897 * pipe, they may return a zero-length result, they may do nothing at
898 * all and timeout, or they may fail in even more bizarrely creative
899 * ways. In these cases the best approach is to use the default
900 * value: only one LUN.
905 int usb_stor_Bulk_transport(struct scsi_cmnd
*srb
, struct us_data
*us
)
907 struct bulk_cb_wrap
*bcb
= (struct bulk_cb_wrap
*) us
->iobuf
;
908 struct bulk_cs_wrap
*bcs
= (struct bulk_cs_wrap
*) us
->iobuf
;
909 unsigned int transfer_length
= scsi_bufflen(srb
);
910 unsigned int residue
;
914 unsigned int cbwlen
= US_BULK_CB_WRAP_LEN
;
916 /* Take care of BULK32 devices; set extra byte to 0 */
917 if (unlikely(us
->fflags
& US_FL_BULK32
)) {
922 /* set up the command wrapper */
923 bcb
->Signature
= cpu_to_le32(US_BULK_CB_SIGN
);
924 bcb
->DataTransferLength
= cpu_to_le32(transfer_length
);
925 bcb
->Flags
= srb
->sc_data_direction
== DMA_FROM_DEVICE
? 1 << 7 : 0;
926 bcb
->Tag
= ++us
->tag
;
927 bcb
->Lun
= srb
->device
->lun
;
928 if (us
->fflags
& US_FL_SCM_MULT_TARG
)
929 bcb
->Lun
|= srb
->device
->id
<< 4;
930 bcb
->Length
= srb
->cmd_len
;
932 /* copy the command payload */
933 memset(bcb
->CDB
, 0, sizeof(bcb
->CDB
));
934 memcpy(bcb
->CDB
, srb
->cmnd
, bcb
->Length
);
936 /* send it to out endpoint */
937 US_DEBUGP("Bulk Command S 0x%x T 0x%x L %d F %d Trg %d LUN %d CL %d\n",
938 le32_to_cpu(bcb
->Signature
), bcb
->Tag
,
939 le32_to_cpu(bcb
->DataTransferLength
), bcb
->Flags
,
940 (bcb
->Lun
>> 4), (bcb
->Lun
& 0x0F),
942 result
= usb_stor_bulk_transfer_buf(us
, us
->send_bulk_pipe
,
944 US_DEBUGP("Bulk command transfer result=%d\n", result
);
945 if (result
!= USB_STOR_XFER_GOOD
)
946 return USB_STOR_TRANSPORT_ERROR
;
949 /* send/receive data payload, if there is any */
951 /* Some USB-IDE converter chips need a 100us delay between the
952 * command phase and the data phase. Some devices need a little
953 * more than that, probably because of clock rate inaccuracies. */
954 if (unlikely(us
->fflags
& US_FL_GO_SLOW
))
957 if (transfer_length
) {
958 unsigned int pipe
= srb
->sc_data_direction
== DMA_FROM_DEVICE
?
959 us
->recv_bulk_pipe
: us
->send_bulk_pipe
;
960 result
= usb_stor_bulk_srb(us
, pipe
, srb
);
961 US_DEBUGP("Bulk data transfer result 0x%x\n", result
);
962 if (result
== USB_STOR_XFER_ERROR
)
963 return USB_STOR_TRANSPORT_ERROR
;
965 /* If the device tried to send back more data than the
966 * amount requested, the spec requires us to transfer
967 * the CSW anyway. Since there's no point retrying the
968 * the command, we'll return fake sense data indicating
969 * Illegal Request, Invalid Field in CDB.
971 if (result
== USB_STOR_XFER_LONG
)
975 /* See flow chart on pg 15 of the Bulk Only Transport spec for
976 * an explanation of how this code works.
979 /* get CSW for device status */
980 US_DEBUGP("Attempting to get CSW...\n");
981 result
= usb_stor_bulk_transfer_buf(us
, us
->recv_bulk_pipe
,
982 bcs
, US_BULK_CS_WRAP_LEN
, &cswlen
);
984 /* Some broken devices add unnecessary zero-length packets to the
985 * end of their data transfers. Such packets show up as 0-length
986 * CSWs. If we encounter such a thing, try to read the CSW again.
988 if (result
== USB_STOR_XFER_SHORT
&& cswlen
== 0) {
989 US_DEBUGP("Received 0-length CSW; retrying...\n");
990 result
= usb_stor_bulk_transfer_buf(us
, us
->recv_bulk_pipe
,
991 bcs
, US_BULK_CS_WRAP_LEN
, &cswlen
);
994 /* did the attempt to read the CSW fail? */
995 if (result
== USB_STOR_XFER_STALLED
) {
997 /* get the status again */
998 US_DEBUGP("Attempting to get CSW (2nd try)...\n");
999 result
= usb_stor_bulk_transfer_buf(us
, us
->recv_bulk_pipe
,
1000 bcs
, US_BULK_CS_WRAP_LEN
, NULL
);
1003 /* if we still have a failure at this point, we're in trouble */
1004 US_DEBUGP("Bulk status result = %d\n", result
);
1005 if (result
!= USB_STOR_XFER_GOOD
)
1006 return USB_STOR_TRANSPORT_ERROR
;
1008 /* check bulk status */
1009 residue
= le32_to_cpu(bcs
->Residue
);
1010 US_DEBUGP("Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n",
1011 le32_to_cpu(bcs
->Signature
), bcs
->Tag
,
1012 residue
, bcs
->Status
);
1013 if (!(bcs
->Tag
== us
->tag
|| (us
->fflags
& US_FL_BULK_IGNORE_TAG
)) ||
1014 bcs
->Status
> US_BULK_STAT_PHASE
) {
1015 US_DEBUGP("Bulk logical error\n");
1016 return USB_STOR_TRANSPORT_ERROR
;
1019 /* Some broken devices report odd signatures, so we do not check them
1020 * for validity against the spec. We store the first one we see,
1021 * and check subsequent transfers for validity against this signature.
1023 if (!us
->bcs_signature
) {
1024 us
->bcs_signature
= bcs
->Signature
;
1025 if (us
->bcs_signature
!= cpu_to_le32(US_BULK_CS_SIGN
))
1026 US_DEBUGP("Learnt BCS signature 0x%08X\n",
1027 le32_to_cpu(us
->bcs_signature
));
1028 } else if (bcs
->Signature
!= us
->bcs_signature
) {
1029 US_DEBUGP("Signature mismatch: got %08X, expecting %08X\n",
1030 le32_to_cpu(bcs
->Signature
),
1031 le32_to_cpu(us
->bcs_signature
));
1032 return USB_STOR_TRANSPORT_ERROR
;
1035 /* try to compute the actual residue, based on how much data
1036 * was really transferred and what the device tells us */
1038 if (!(us
->fflags
& US_FL_IGNORE_RESIDUE
)) {
1039 residue
= min(residue
, transfer_length
);
1040 scsi_set_resid(srb
, max(scsi_get_resid(srb
),
1045 /* based on the status code, we report good or bad */
1046 switch (bcs
->Status
) {
1047 case US_BULK_STAT_OK
:
1048 /* device babbled -- return fake sense data */
1050 memcpy(srb
->sense_buffer
,
1051 usb_stor_sense_invalidCDB
,
1052 sizeof(usb_stor_sense_invalidCDB
));
1053 return USB_STOR_TRANSPORT_NO_SENSE
;
1056 /* command good -- note that data could be short */
1057 return USB_STOR_TRANSPORT_GOOD
;
1059 case US_BULK_STAT_FAIL
:
1060 /* command failed */
1061 return USB_STOR_TRANSPORT_FAILED
;
1063 case US_BULK_STAT_PHASE
:
1064 /* phase error -- note that a transport reset will be
1065 * invoked by the invoke_transport() function
1067 return USB_STOR_TRANSPORT_ERROR
;
1070 /* we should never get here, but if we do, we're in trouble */
1071 return USB_STOR_TRANSPORT_ERROR
;
1074 /***********************************************************************
1076 ***********************************************************************/
1078 /* This is the common part of the device reset code.
1080 * It's handy that every transport mechanism uses the control endpoint for
1083 * Basically, we send a reset with a 5-second timeout, so we don't get
1084 * jammed attempting to do the reset.
1086 static int usb_stor_reset_common(struct us_data
*us
,
1087 u8 request
, u8 requesttype
,
1088 u16 value
, u16 index
, void *data
, u16 size
)
1093 if (test_bit(US_FLIDX_DISCONNECTING
, &us
->dflags
)) {
1094 US_DEBUGP("No reset during disconnect\n");
1098 result
= usb_stor_control_msg(us
, us
->send_ctrl_pipe
,
1099 request
, requesttype
, value
, index
, data
, size
,
1102 US_DEBUGP("Soft reset failed: %d\n", result
);
1106 /* Give the device some time to recover from the reset,
1107 * but don't delay disconnect processing. */
1108 wait_event_interruptible_timeout(us
->delay_wait
,
1109 test_bit(US_FLIDX_DISCONNECTING
, &us
->dflags
),
1111 if (test_bit(US_FLIDX_DISCONNECTING
, &us
->dflags
)) {
1112 US_DEBUGP("Reset interrupted by disconnect\n");
1116 US_DEBUGP("Soft reset: clearing bulk-in endpoint halt\n");
1117 result
= usb_stor_clear_halt(us
, us
->recv_bulk_pipe
);
1119 US_DEBUGP("Soft reset: clearing bulk-out endpoint halt\n");
1120 result2
= usb_stor_clear_halt(us
, us
->send_bulk_pipe
);
1122 /* return a result code based on the result of the clear-halts */
1126 US_DEBUGP("Soft reset failed\n");
1128 US_DEBUGP("Soft reset done\n");
1132 /* This issues a CB[I] Reset to the device in question
1134 #define CB_RESET_CMD_SIZE 12
1136 int usb_stor_CB_reset(struct us_data
*us
)
1138 US_DEBUGP("%s called\n", __func__
);
1140 memset(us
->iobuf
, 0xFF, CB_RESET_CMD_SIZE
);
1141 us
->iobuf
[0] = SEND_DIAGNOSTIC
;
1143 return usb_stor_reset_common(us
, US_CBI_ADSC
,
1144 USB_TYPE_CLASS
| USB_RECIP_INTERFACE
,
1145 0, us
->ifnum
, us
->iobuf
, CB_RESET_CMD_SIZE
);
1148 /* This issues a Bulk-only Reset to the device in question, including
1149 * clearing the subsequent endpoint halts that may occur.
1151 int usb_stor_Bulk_reset(struct us_data
*us
)
1153 US_DEBUGP("%s called\n", __func__
);
1155 return usb_stor_reset_common(us
, US_BULK_RESET_REQUEST
,
1156 USB_TYPE_CLASS
| USB_RECIP_INTERFACE
,
1157 0, us
->ifnum
, NULL
, 0);
1160 /* Issue a USB port reset to the device. The caller must not hold
1163 int usb_stor_port_reset(struct us_data
*us
)
1165 int result
, rc_lock
;
1168 usb_lock_device_for_reset(us
->pusb_dev
, us
->pusb_intf
);
1170 US_DEBUGP("unable to lock device for reset: %d\n", result
);
1172 /* Were we disconnected while waiting for the lock? */
1173 if (test_bit(US_FLIDX_DISCONNECTING
, &us
->dflags
)) {
1175 US_DEBUGP("No reset during disconnect\n");
1177 result
= usb_reset_composite_device(
1178 us
->pusb_dev
, us
->pusb_intf
);
1179 US_DEBUGP("usb_reset_composite_device returns %d\n",
1183 usb_unlock_device(us
->pusb_dev
);