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/config.h>
49 #include <linux/sched.h>
50 #include <linux/errno.h>
51 #include <linux/slab.h>
53 #include <scsi/scsi.h>
54 #include <scsi/scsi_cmnd.h>
55 #include <scsi/scsi_device.h>
58 #include "transport.h"
64 /***********************************************************************
65 * Data transfer routines
66 ***********************************************************************/
69 * This is subtle, so pay attention:
70 * ---------------------------------
71 * We're very concerned about races with a command abort. Hanging this code
72 * is a sure fire way to hang the kernel. (Note that this discussion applies
73 * only to transactions resulting from a scsi queued-command, since only
74 * these transactions are subject to a scsi abort. Other transactions, such
75 * as those occurring during device-specific initialization, must be handled
76 * by a separate code path.)
78 * The abort function (usb_storage_command_abort() in scsiglue.c) first
79 * sets the machine state and the ABORTING bit in us->flags to prevent
80 * new URBs from being submitted. It then calls usb_stor_stop_transport()
81 * below, which atomically tests-and-clears the URB_ACTIVE bit in us->flags
82 * to see if the current_urb needs to be stopped. Likewise, the SG_ACTIVE
83 * bit is tested to see if the current_sg scatter-gather request needs to be
84 * stopped. The timeout callback routine does much the same thing.
86 * When a disconnect occurs, the DISCONNECTING bit in us->flags is set to
87 * prevent new URBs from being submitted, and usb_stor_stop_transport() is
88 * called to stop any ongoing requests.
90 * The submit function first verifies that the submitting is allowed
91 * (neither ABORTING nor DISCONNECTING bits are set) and that the submit
92 * completes without errors, and only then sets the URB_ACTIVE bit. This
93 * prevents the stop_transport() function from trying to cancel the URB
94 * while the submit call is underway. Next, the submit function must test
95 * the flags to see if an abort or disconnect occurred during the submission
96 * or before the URB_ACTIVE bit was set. If so, it's essential to cancel
97 * the URB if it hasn't been cancelled already (i.e., if the URB_ACTIVE bit
98 * is still set). Either way, the function must then wait for the URB to
99 * finish. Note that the URB can still be in progress even after a call to
100 * usb_unlink_urb() returns.
102 * The idea is that (1) once the ABORTING or DISCONNECTING bit is set,
103 * either the stop_transport() function or the submitting function
104 * is guaranteed to call usb_unlink_urb() for an active URB,
105 * and (2) test_and_clear_bit() prevents usb_unlink_urb() from being
106 * called more than once or from being called during usb_submit_urb().
109 /* This is the completion handler which will wake us up when an URB
112 static void usb_stor_blocking_completion(struct urb *urb, struct pt_regs *regs)
114 struct completion *urb_done_ptr = (struct completion *)urb->context;
116 complete(urb_done_ptr);
119 /* This is the timeout handler which will cancel an URB when its timeout
122 static void timeout_handler(unsigned long us_)
124 struct us_data *us = (struct us_data *) us_;
126 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) {
127 US_DEBUGP("Timeout -- cancelling URB\n");
128 usb_unlink_urb(us->current_urb);
132 /* This is the common part of the URB message submission code
134 * All URBs from the usb-storage driver involved in handling a queued scsi
135 * command _must_ pass through this function (or something like it) for the
136 * abort mechanisms to work properly.
138 static int usb_stor_msg_common(struct us_data *us, int timeout)
140 struct completion urb_done;
141 struct timer_list to_timer;
144 /* don't submit URBs during abort/disconnect processing */
145 if (us->flags & ABORTING_OR_DISCONNECTING)
148 /* set up data structures for the wakeup system */
149 init_completion(&urb_done);
151 /* fill the common fields in the URB */
152 us->current_urb->context = &urb_done;
153 us->current_urb->actual_length = 0;
154 us->current_urb->error_count = 0;
155 us->current_urb->status = 0;
157 /* we assume that if transfer_buffer isn't us->iobuf then it
158 * hasn't been mapped for DMA. Yes, this is clunky, but it's
159 * easier than always having the caller tell us whether the
160 * transfer buffer has already been mapped. */
161 us->current_urb->transfer_flags = URB_NO_SETUP_DMA_MAP;
162 if (us->current_urb->transfer_buffer == us->iobuf)
163 us->current_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
164 us->current_urb->transfer_dma = us->iobuf_dma;
165 us->current_urb->setup_dma = us->cr_dma;
168 status = usb_submit_urb(us->current_urb, GFP_NOIO);
170 /* something went wrong */
174 /* since the URB has been submitted successfully, it's now okay
176 set_bit(US_FLIDX_URB_ACTIVE, &us->flags);
178 /* did an abort/disconnect occur during the submission? */
179 if (us->flags & ABORTING_OR_DISCONNECTING) {
181 /* cancel the URB, if it hasn't been cancelled already */
182 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) {
183 US_DEBUGP("-- cancelling URB\n");
184 usb_unlink_urb(us->current_urb);
188 /* submit the timeout timer, if a timeout was requested */
190 init_timer(&to_timer);
191 to_timer.expires = jiffies + timeout;
192 to_timer.function = timeout_handler;
193 to_timer.data = (unsigned long) us;
194 add_timer(&to_timer);
197 /* wait for the completion of the URB */
198 wait_for_completion(&urb_done);
199 clear_bit(US_FLIDX_URB_ACTIVE, &us->flags);
201 /* clean up the timeout timer */
203 del_timer_sync(&to_timer);
205 /* return the URB status */
206 return us->current_urb->status;
210 * Transfer one control message, with timeouts, and allowing early
211 * termination. Return codes are usual -Exxx, *not* USB_STOR_XFER_xxx.
213 int usb_stor_control_msg(struct us_data *us, unsigned int pipe,
214 u8 request, u8 requesttype, u16 value, u16 index,
215 void *data, u16 size, int timeout)
219 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
220 __FUNCTION__, request, requesttype,
223 /* fill in the devrequest structure */
224 us->cr->bRequestType = requesttype;
225 us->cr->bRequest = request;
226 us->cr->wValue = cpu_to_le16(value);
227 us->cr->wIndex = cpu_to_le16(index);
228 us->cr->wLength = cpu_to_le16(size);
230 /* fill and submit the URB */
231 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe,
232 (unsigned char*) us->cr, data, size,
233 usb_stor_blocking_completion, NULL);
234 status = usb_stor_msg_common(us, timeout);
236 /* return the actual length of the data transferred if no error */
238 status = us->current_urb->actual_length;
242 /* This is a version of usb_clear_halt() that allows early termination and
243 * doesn't read the status from the device -- this is because some devices
244 * crash their internal firmware when the status is requested after a halt.
246 * A definitive list of these 'bad' devices is too difficult to maintain or
247 * make complete enough to be useful. This problem was first observed on the
248 * Hagiwara FlashGate DUAL unit. However, bus traces reveal that neither
249 * MacOS nor Windows checks the status after clearing a halt.
251 * Since many vendors in this space limit their testing to interoperability
252 * with these two OSes, specification violations like this one are common.
254 int usb_stor_clear_halt(struct us_data *us, unsigned int pipe)
257 int endp = usb_pipeendpoint(pipe);
259 if (usb_pipein (pipe))
262 result = usb_stor_control_msg(us, us->send_ctrl_pipe,
263 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
264 USB_ENDPOINT_HALT, endp,
267 /* reset the endpoint toggle */
269 usb_settoggle(us->pusb_dev, usb_pipeendpoint(pipe),
270 usb_pipeout(pipe), 0);
272 US_DEBUGP("%s: result = %d\n", __FUNCTION__, result);
278 * Interpret the results of a URB transfer
280 * This function prints appropriate debugging messages, clears halts on
281 * non-control endpoints, and translates the status to the corresponding
282 * USB_STOR_XFER_xxx return code.
284 static int interpret_urb_result(struct us_data *us, unsigned int pipe,
285 unsigned int length, int result, unsigned int partial)
287 US_DEBUGP("Status code %d; transferred %u/%u\n",
288 result, partial, length);
291 /* no error code; did we send all the data? */
293 if (partial != length) {
294 US_DEBUGP("-- short transfer\n");
295 return USB_STOR_XFER_SHORT;
298 US_DEBUGP("-- transfer complete\n");
299 return USB_STOR_XFER_GOOD;
303 /* for control endpoints, (used by CB[I]) a stall indicates
304 * a failed command */
305 if (usb_pipecontrol(pipe)) {
306 US_DEBUGP("-- stall on control pipe\n");
307 return USB_STOR_XFER_STALLED;
310 /* for other sorts of endpoint, clear the stall */
311 US_DEBUGP("clearing endpoint halt for pipe 0x%x\n", pipe);
312 if (usb_stor_clear_halt(us, pipe) < 0)
313 return USB_STOR_XFER_ERROR;
314 return USB_STOR_XFER_STALLED;
316 /* timeout or excessively long NAK */
318 US_DEBUGP("-- timeout or NAK\n");
319 return USB_STOR_XFER_ERROR;
321 /* babble - the device tried to send more than we wanted to read */
323 US_DEBUGP("-- babble\n");
324 return USB_STOR_XFER_LONG;
326 /* the transfer was cancelled by abort, disconnect, or timeout */
328 US_DEBUGP("-- transfer cancelled\n");
329 return USB_STOR_XFER_ERROR;
331 /* short scatter-gather read transfer */
333 US_DEBUGP("-- short read transfer\n");
334 return USB_STOR_XFER_SHORT;
336 /* abort or disconnect in progress */
338 US_DEBUGP("-- abort or disconnect in progress\n");
339 return USB_STOR_XFER_ERROR;
341 /* the catch-all error case */
343 US_DEBUGP("-- unknown error\n");
344 return USB_STOR_XFER_ERROR;
349 * Transfer one control message, without timeouts, but allowing early
350 * termination. Return codes are USB_STOR_XFER_xxx.
352 int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe,
353 u8 request, u8 requesttype, u16 value, u16 index,
354 void *data, u16 size)
358 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
359 __FUNCTION__, request, requesttype,
362 /* fill in the devrequest structure */
363 us->cr->bRequestType = requesttype;
364 us->cr->bRequest = request;
365 us->cr->wValue = cpu_to_le16(value);
366 us->cr->wIndex = cpu_to_le16(index);
367 us->cr->wLength = cpu_to_le16(size);
369 /* fill and submit the URB */
370 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe,
371 (unsigned char*) us->cr, data, size,
372 usb_stor_blocking_completion, NULL);
373 result = usb_stor_msg_common(us, 0);
375 return interpret_urb_result(us, pipe, size, result,
376 us->current_urb->actual_length);
380 * Receive one interrupt buffer, without timeouts, but allowing early
381 * termination. Return codes are USB_STOR_XFER_xxx.
383 * This routine always uses us->recv_intr_pipe as the pipe and
384 * us->ep_bInterval as the interrupt interval.
386 static int usb_stor_intr_transfer(struct us_data *us, void *buf,
390 unsigned int pipe = us->recv_intr_pipe;
393 US_DEBUGP("%s: xfer %u bytes\n", __FUNCTION__, length);
395 /* calculate the max packet size */
396 maxp = usb_maxpacket(us->pusb_dev, pipe, usb_pipeout(pipe));
400 /* fill and submit the URB */
401 usb_fill_int_urb(us->current_urb, us->pusb_dev, pipe, buf,
402 maxp, usb_stor_blocking_completion, NULL,
404 result = usb_stor_msg_common(us, 0);
406 return interpret_urb_result(us, pipe, length, result,
407 us->current_urb->actual_length);
411 * Transfer one buffer via bulk pipe, without timeouts, but allowing early
412 * termination. Return codes are USB_STOR_XFER_xxx. If the bulk pipe
413 * stalls during the transfer, the halt is automatically cleared.
415 int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe,
416 void *buf, unsigned int length, unsigned int *act_len)
420 US_DEBUGP("%s: xfer %u bytes\n", __FUNCTION__, length);
422 /* fill and submit the URB */
423 usb_fill_bulk_urb(us->current_urb, us->pusb_dev, pipe, buf, length,
424 usb_stor_blocking_completion, NULL);
425 result = usb_stor_msg_common(us, 0);
427 /* store the actual length of the data transferred */
429 *act_len = us->current_urb->actual_length;
430 return interpret_urb_result(us, pipe, length, result,
431 us->current_urb->actual_length);
435 * Transfer a scatter-gather list via bulk transfer
437 * This function does basically the same thing as usb_stor_bulk_transfer_buf()
438 * above, but it uses the usbcore scatter-gather library.
440 static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
441 struct scatterlist *sg, int num_sg, unsigned int length,
442 unsigned int *act_len)
446 /* don't submit s-g requests during abort/disconnect processing */
447 if (us->flags & ABORTING_OR_DISCONNECTING)
448 return USB_STOR_XFER_ERROR;
450 /* initialize the scatter-gather request block */
451 US_DEBUGP("%s: xfer %u bytes, %d entries\n", __FUNCTION__,
453 result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0,
454 sg, num_sg, length, SLAB_NOIO);
456 US_DEBUGP("usb_sg_init returned %d\n", result);
457 return USB_STOR_XFER_ERROR;
460 /* since the block has been initialized successfully, it's now
461 * okay to cancel it */
462 set_bit(US_FLIDX_SG_ACTIVE, &us->flags);
464 /* did an abort/disconnect occur during the submission? */
465 if (us->flags & ABORTING_OR_DISCONNECTING) {
467 /* cancel the request, if it hasn't been cancelled already */
468 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) {
469 US_DEBUGP("-- cancelling sg request\n");
470 usb_sg_cancel(&us->current_sg);
474 /* wait for the completion of the transfer */
475 usb_sg_wait(&us->current_sg);
476 clear_bit(US_FLIDX_SG_ACTIVE, &us->flags);
478 result = us->current_sg.status;
480 *act_len = us->current_sg.bytes;
481 return interpret_urb_result(us, pipe, length, result,
482 us->current_sg.bytes);
486 * Transfer an entire SCSI command's worth of data payload over the bulk
489 * Note that this uses usb_stor_bulk_transfer_buf() and
490 * usb_stor_bulk_transfer_sglist() to achieve its goals --
491 * this function simply determines whether we're going to use
492 * scatter-gather or not, and acts appropriately.
494 int usb_stor_bulk_transfer_sg(struct us_data* us, unsigned int pipe,
495 void *buf, unsigned int length_left, int use_sg, int *residual)
498 unsigned int partial;
500 /* are we scatter-gathering? */
502 /* use the usb core scatter-gather primitives */
503 result = usb_stor_bulk_transfer_sglist(us, pipe,
504 (struct scatterlist *) buf, use_sg,
505 length_left, &partial);
506 length_left -= partial;
508 /* no scatter-gather, just make the request */
509 result = usb_stor_bulk_transfer_buf(us, pipe, buf,
510 length_left, &partial);
511 length_left -= partial;
514 /* store the residual and return the error code */
516 *residual = length_left;
520 /***********************************************************************
522 ***********************************************************************/
524 /* Invoke the transport and basic error-handling/recovery methods
526 * This is used by the protocol layers to actually send the message to
527 * the device and receive the response.
529 void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
534 /* send the command to the transport layer */
536 result = us->transport(srb, us);
538 /* if the command gets aborted by the higher layers, we need to
539 * short-circuit all other processing
541 if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
542 US_DEBUGP("-- command was aborted\n");
543 srb->result = DID_ABORT << 16;
547 /* if there is a transport error, reset and don't auto-sense */
548 if (result == USB_STOR_TRANSPORT_ERROR) {
549 US_DEBUGP("-- transport indicates error, resetting\n");
550 srb->result = DID_ERROR << 16;
554 /* if the transport provided its own sense data, don't auto-sense */
555 if (result == USB_STOR_TRANSPORT_NO_SENSE) {
556 srb->result = SAM_STAT_CHECK_CONDITION;
560 srb->result = SAM_STAT_GOOD;
562 /* Determine if we need to auto-sense
564 * I normally don't use a flag like this, but it's almost impossible
565 * to understand what's going on here if I don't.
570 * If we're running the CB transport, which is incapable
571 * of determining status on its own, we will auto-sense
572 * unless the operation involved a data-in transfer. Devices
573 * can signal most data-in errors by stalling the bulk-in pipe.
575 if ((us->protocol == US_PR_CB || us->protocol == US_PR_DPCM_USB) &&
576 srb->sc_data_direction != DMA_FROM_DEVICE) {
577 US_DEBUGP("-- CB transport device requiring auto-sense\n");
582 * If we have a failure, we're going to do a REQUEST_SENSE
583 * automatically. Note that we differentiate between a command
584 * "failure" and an "error" in the transport mechanism.
586 if (result == USB_STOR_TRANSPORT_FAILED) {
587 US_DEBUGP("-- transport indicates command failure\n");
592 * A short transfer on a command where we don't expect it
593 * is unusual, but it doesn't mean we need to auto-sense.
595 if ((srb->resid > 0) &&
596 !((srb->cmnd[0] == REQUEST_SENSE) ||
597 (srb->cmnd[0] == INQUIRY) ||
598 (srb->cmnd[0] == MODE_SENSE) ||
599 (srb->cmnd[0] == LOG_SENSE) ||
600 (srb->cmnd[0] == MODE_SENSE_10))) {
601 US_DEBUGP("-- unexpectedly short transfer\n");
604 /* Now, if we need to do the auto-sense, let's do it */
605 if (need_auto_sense) {
607 void* old_request_buffer;
608 unsigned short old_sg;
609 unsigned old_request_bufflen;
610 unsigned char old_sc_data_direction;
611 unsigned char old_cmd_len;
612 unsigned char old_cmnd[MAX_COMMAND_SIZE];
615 US_DEBUGP("Issuing auto-REQUEST_SENSE\n");
617 /* save the old command */
618 memcpy(old_cmnd, srb->cmnd, MAX_COMMAND_SIZE);
619 old_cmd_len = srb->cmd_len;
621 /* set the command and the LUN */
622 memset(srb->cmnd, 0, MAX_COMMAND_SIZE);
623 srb->cmnd[0] = REQUEST_SENSE;
624 srb->cmnd[1] = old_cmnd[1] & 0xE0;
627 /* FIXME: we must do the protocol translation here */
628 if (us->subclass == US_SC_RBC || us->subclass == US_SC_SCSI)
633 /* set the transfer direction */
634 old_sc_data_direction = srb->sc_data_direction;
635 srb->sc_data_direction = DMA_FROM_DEVICE;
637 /* use the new buffer we have */
638 old_request_buffer = srb->request_buffer;
639 srb->request_buffer = srb->sense_buffer;
641 /* set the buffer length for transfer */
642 old_request_bufflen = srb->request_bufflen;
643 srb->request_bufflen = 18;
645 /* set up for no scatter-gather use */
646 old_sg = srb->use_sg;
649 /* issue the auto-sense command */
650 old_resid = srb->resid;
652 temp_result = us->transport(us->srb, us);
654 /* let's clean up right away */
655 srb->resid = old_resid;
656 srb->request_buffer = old_request_buffer;
657 srb->request_bufflen = old_request_bufflen;
658 srb->use_sg = old_sg;
659 srb->sc_data_direction = old_sc_data_direction;
660 srb->cmd_len = old_cmd_len;
661 memcpy(srb->cmnd, old_cmnd, MAX_COMMAND_SIZE);
663 if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
664 US_DEBUGP("-- auto-sense aborted\n");
665 srb->result = DID_ABORT << 16;
668 if (temp_result != USB_STOR_TRANSPORT_GOOD) {
669 US_DEBUGP("-- auto-sense failure\n");
671 /* we skip the reset if this happens to be a
672 * multi-target device, since failure of an
673 * auto-sense is perfectly valid
675 srb->result = DID_ERROR << 16;
676 if (!(us->flags & US_FL_SCM_MULT_TARG))
681 US_DEBUGP("-- Result from auto-sense is %d\n", temp_result);
682 US_DEBUGP("-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n",
683 srb->sense_buffer[0],
684 srb->sense_buffer[2] & 0xf,
685 srb->sense_buffer[12],
686 srb->sense_buffer[13]);
687 #ifdef CONFIG_USB_STORAGE_DEBUG
689 srb->sense_buffer[2] & 0xf,
690 srb->sense_buffer[12],
691 srb->sense_buffer[13]);
694 /* set the result so the higher layers expect this data */
695 srb->result = SAM_STAT_CHECK_CONDITION;
697 /* If things are really okay, then let's show that. Zero
698 * out the sense buffer so the higher layers won't realize
699 * we did an unsolicited auto-sense. */
700 if (result == USB_STOR_TRANSPORT_GOOD &&
701 /* Filemark 0, ignore EOM, ILI 0, no sense */
702 (srb->sense_buffer[2] & 0xaf) == 0 &&
704 srb->sense_buffer[12] == 0 &&
705 srb->sense_buffer[13] == 0) {
706 srb->result = SAM_STAT_GOOD;
707 srb->sense_buffer[0] = 0x0;
711 /* Did we transfer less than the minimum amount required? */
712 if (srb->result == SAM_STAT_GOOD &&
713 srb->request_bufflen - srb->resid < srb->underflow)
714 srb->result = (DID_ERROR << 16) | (SUGGEST_RETRY << 24);
718 /* Error and abort processing: try to resynchronize with the device
719 * by issuing a port reset. If that fails, try a class-specific
723 /* Let the SCSI layer know we are doing a reset, set the
724 * RESETTING bit, and clear the ABORTING bit so that the reset
726 scsi_lock(us_to_host(us));
727 usb_stor_report_bus_reset(us);
728 set_bit(US_FLIDX_RESETTING, &us->flags);
729 clear_bit(US_FLIDX_ABORTING, &us->flags);
730 scsi_unlock(us_to_host(us));
732 result = usb_stor_port_reset(us);
734 scsi_lock(us_to_host(us));
735 usb_stor_report_device_reset(us);
736 scsi_unlock(us_to_host(us));
737 us->transport_reset(us);
739 clear_bit(US_FLIDX_RESETTING, &us->flags);
742 /* Stop the current URB transfer */
743 void usb_stor_stop_transport(struct us_data *us)
745 US_DEBUGP("%s called\n", __FUNCTION__);
747 /* If the state machine is blocked waiting for an URB,
748 * let's wake it up. The test_and_clear_bit() call
749 * guarantees that if a URB has just been submitted,
750 * it won't be cancelled more than once. */
751 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) {
752 US_DEBUGP("-- cancelling URB\n");
753 usb_unlink_urb(us->current_urb);
756 /* If we are waiting for a scatter-gather operation, cancel it. */
757 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) {
758 US_DEBUGP("-- cancelling sg request\n");
759 usb_sg_cancel(&us->current_sg);
764 * Control/Bulk/Interrupt transport
767 int usb_stor_CBI_transport(struct scsi_cmnd *srb, struct us_data *us)
769 unsigned int transfer_length = srb->request_bufflen;
770 unsigned int pipe = 0;
774 /* let's send the command via the control pipe */
775 result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe,
777 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
778 us->ifnum, srb->cmnd, srb->cmd_len);
780 /* check the return code for the command */
781 US_DEBUGP("Call to usb_stor_ctrl_transfer() returned %d\n", result);
783 /* if we stalled the command, it means command failed */
784 if (result == USB_STOR_XFER_STALLED) {
785 return USB_STOR_TRANSPORT_FAILED;
788 /* Uh oh... serious problem here */
789 if (result != USB_STOR_XFER_GOOD) {
790 return USB_STOR_TRANSPORT_ERROR;
794 /* transfer the data payload for this command, if one exists*/
795 if (transfer_length) {
796 pipe = srb->sc_data_direction == DMA_FROM_DEVICE ?
797 us->recv_bulk_pipe : us->send_bulk_pipe;
798 result = usb_stor_bulk_transfer_sg(us, pipe,
799 srb->request_buffer, transfer_length,
800 srb->use_sg, &srb->resid);
801 US_DEBUGP("CBI data stage result is 0x%x\n", result);
803 /* if we stalled the data transfer it means command failed */
804 if (result == USB_STOR_XFER_STALLED)
805 return USB_STOR_TRANSPORT_FAILED;
806 if (result > USB_STOR_XFER_STALLED)
807 return USB_STOR_TRANSPORT_ERROR;
811 result = usb_stor_intr_transfer(us, us->iobuf, 2);
812 US_DEBUGP("Got interrupt data (0x%x, 0x%x)\n",
813 us->iobuf[0], us->iobuf[1]);
814 if (result != USB_STOR_XFER_GOOD)
815 return USB_STOR_TRANSPORT_ERROR;
817 /* UFI gives us ASC and ASCQ, like a request sense
819 * REQUEST_SENSE and INQUIRY don't affect the sense data on UFI
820 * devices, so we ignore the information for those commands. Note
821 * that this means we could be ignoring a real error on these
822 * commands, but that can't be helped.
824 if (us->subclass == US_SC_UFI) {
825 if (srb->cmnd[0] == REQUEST_SENSE ||
826 srb->cmnd[0] == INQUIRY)
827 return USB_STOR_TRANSPORT_GOOD;
830 return USB_STOR_TRANSPORT_GOOD;
833 /* If not UFI, we interpret the data as a result code
834 * The first byte should always be a 0x0.
836 * Some bogus devices don't follow that rule. They stuff the ASC
837 * into the first byte -- so if it's non-zero, call it a failure.
840 US_DEBUGP("CBI IRQ data showed reserved bType 0x%x\n",
846 /* The second byte & 0x0F should be 0x0 for good, otherwise error */
847 switch (us->iobuf[1] & 0x0F) {
849 return USB_STOR_TRANSPORT_GOOD;
853 return USB_STOR_TRANSPORT_ERROR;
855 /* the CBI spec requires that the bulk pipe must be cleared
856 * following any data-in/out command failure (section 2.4.3.1.3)
860 usb_stor_clear_halt(us, pipe);
861 return USB_STOR_TRANSPORT_FAILED;
865 * Control/Bulk transport
867 int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us)
869 unsigned int transfer_length = srb->request_bufflen;
873 /* let's send the command via the control pipe */
874 result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe,
876 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
877 us->ifnum, srb->cmnd, srb->cmd_len);
879 /* check the return code for the command */
880 US_DEBUGP("Call to usb_stor_ctrl_transfer() returned %d\n", result);
882 /* if we stalled the command, it means command failed */
883 if (result == USB_STOR_XFER_STALLED) {
884 return USB_STOR_TRANSPORT_FAILED;
887 /* Uh oh... serious problem here */
888 if (result != USB_STOR_XFER_GOOD) {
889 return USB_STOR_TRANSPORT_ERROR;
893 /* transfer the data payload for this command, if one exists*/
894 if (transfer_length) {
895 unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ?
896 us->recv_bulk_pipe : us->send_bulk_pipe;
897 result = usb_stor_bulk_transfer_sg(us, pipe,
898 srb->request_buffer, transfer_length,
899 srb->use_sg, &srb->resid);
900 US_DEBUGP("CB data stage result is 0x%x\n", result);
902 /* if we stalled the data transfer it means command failed */
903 if (result == USB_STOR_XFER_STALLED)
904 return USB_STOR_TRANSPORT_FAILED;
905 if (result > USB_STOR_XFER_STALLED)
906 return USB_STOR_TRANSPORT_ERROR;
910 /* NOTE: CB does not have a status stage. Silly, I know. So
911 * we have to catch this at a higher level.
913 return USB_STOR_TRANSPORT_GOOD;
917 * Bulk only transport
920 /* Determine what the maximum LUN supported is */
921 int usb_stor_Bulk_max_lun(struct us_data *us)
925 /* issue the command */
926 result = usb_stor_control_msg(us, us->recv_ctrl_pipe,
928 USB_DIR_IN | USB_TYPE_CLASS |
930 0, us->ifnum, us->iobuf, 1, HZ);
932 US_DEBUGP("GetMaxLUN command result is %d, data is %d\n",
933 result, us->iobuf[0]);
935 /* if we have a successful request, return the result */
940 * Some devices (i.e. Iomega Zip100) need this -- apparently
941 * the bulk pipes get STALLed when the GetMaxLUN request is
942 * processed. This is, in theory, harmless to all other devices
943 * (regardless of if they stall or not).
945 if (result == -EPIPE) {
946 usb_stor_clear_halt(us, us->recv_bulk_pipe);
947 usb_stor_clear_halt(us, us->send_bulk_pipe);
951 * Some devices don't like GetMaxLUN. They may STALL the control
952 * pipe, they may return a zero-length result, they may do nothing at
953 * all and timeout, or they may fail in even more bizarrely creative
954 * ways. In these cases the best approach is to use the default
955 * value: only one LUN.
960 int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
962 struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf;
963 struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf;
964 unsigned int transfer_length = srb->request_bufflen;
965 unsigned int residue;
969 unsigned int cbwlen = US_BULK_CB_WRAP_LEN;
971 /* Take care of BULK32 devices; set extra byte to 0 */
972 if ( unlikely(us->flags & US_FL_BULK32)) {
977 /* set up the command wrapper */
978 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
979 bcb->DataTransferLength = cpu_to_le32(transfer_length);
980 bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ? 1 << 7 : 0;
981 bcb->Tag = ++us->tag;
982 bcb->Lun = srb->device->lun;
983 if (us->flags & US_FL_SCM_MULT_TARG)
984 bcb->Lun |= srb->device->id << 4;
985 bcb->Length = srb->cmd_len;
987 /* copy the command payload */
988 memset(bcb->CDB, 0, sizeof(bcb->CDB));
989 memcpy(bcb->CDB, srb->cmnd, bcb->Length);
991 /* send it to out endpoint */
992 US_DEBUGP("Bulk Command S 0x%x T 0x%x L %d F %d Trg %d LUN %d CL %d\n",
993 le32_to_cpu(bcb->Signature), bcb->Tag,
994 le32_to_cpu(bcb->DataTransferLength), bcb->Flags,
995 (bcb->Lun >> 4), (bcb->Lun & 0x0F),
997 result = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
999 US_DEBUGP("Bulk command transfer result=%d\n", result);
1000 if (result != USB_STOR_XFER_GOOD)
1001 return USB_STOR_TRANSPORT_ERROR;
1004 /* send/receive data payload, if there is any */
1006 /* Some USB-IDE converter chips need a 100us delay between the
1007 * command phase and the data phase. Some devices need a little
1008 * more than that, probably because of clock rate inaccuracies. */
1009 if (unlikely(us->flags & US_FL_GO_SLOW))
1012 if (transfer_length) {
1013 unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ?
1014 us->recv_bulk_pipe : us->send_bulk_pipe;
1015 result = usb_stor_bulk_transfer_sg(us, pipe,
1016 srb->request_buffer, transfer_length,
1017 srb->use_sg, &srb->resid);
1018 US_DEBUGP("Bulk data transfer result 0x%x\n", result);
1019 if (result == USB_STOR_XFER_ERROR)
1020 return USB_STOR_TRANSPORT_ERROR;
1022 /* If the device tried to send back more data than the
1023 * amount requested, the spec requires us to transfer
1024 * the CSW anyway. Since there's no point retrying the
1025 * the command, we'll return fake sense data indicating
1026 * Illegal Request, Invalid Field in CDB.
1028 if (result == USB_STOR_XFER_LONG)
1032 /* See flow chart on pg 15 of the Bulk Only Transport spec for
1033 * an explanation of how this code works.
1036 /* get CSW for device status */
1037 US_DEBUGP("Attempting to get CSW...\n");
1038 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1039 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
1041 /* Some broken devices add unnecessary zero-length packets to the
1042 * end of their data transfers. Such packets show up as 0-length
1043 * CSWs. If we encounter such a thing, try to read the CSW again.
1045 if (result == USB_STOR_XFER_SHORT && cswlen == 0) {
1046 US_DEBUGP("Received 0-length CSW; retrying...\n");
1047 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1048 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
1051 /* did the attempt to read the CSW fail? */
1052 if (result == USB_STOR_XFER_STALLED) {
1054 /* get the status again */
1055 US_DEBUGP("Attempting to get CSW (2nd try)...\n");
1056 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1057 bcs, US_BULK_CS_WRAP_LEN, NULL);
1060 /* if we still have a failure at this point, we're in trouble */
1061 US_DEBUGP("Bulk status result = %d\n", result);
1062 if (result != USB_STOR_XFER_GOOD)
1063 return USB_STOR_TRANSPORT_ERROR;
1065 /* check bulk status */
1066 residue = le32_to_cpu(bcs->Residue);
1067 US_DEBUGP("Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n",
1068 le32_to_cpu(bcs->Signature), bcs->Tag,
1069 residue, bcs->Status);
1070 if (bcs->Tag != us->tag || bcs->Status > US_BULK_STAT_PHASE) {
1071 US_DEBUGP("Bulk logical error\n");
1072 return USB_STOR_TRANSPORT_ERROR;
1075 /* Some broken devices report odd signatures, so we do not check them
1076 * for validity against the spec. We store the first one we see,
1077 * and check subsequent transfers for validity against this signature.
1079 if (!us->bcs_signature) {
1080 us->bcs_signature = bcs->Signature;
1081 if (us->bcs_signature != cpu_to_le32(US_BULK_CS_SIGN))
1082 US_DEBUGP("Learnt BCS signature 0x%08X\n",
1083 le32_to_cpu(us->bcs_signature));
1084 } else if (bcs->Signature != us->bcs_signature) {
1085 US_DEBUGP("Signature mismatch: got %08X, expecting %08X\n",
1086 le32_to_cpu(bcs->Signature),
1087 le32_to_cpu(us->bcs_signature));
1088 return USB_STOR_TRANSPORT_ERROR;
1091 /* try to compute the actual residue, based on how much data
1092 * was really transferred and what the device tells us */
1094 if (!(us->flags & US_FL_IGNORE_RESIDUE)) {
1095 residue = min(residue, transfer_length);
1096 srb->resid = max(srb->resid, (int) residue);
1100 /* based on the status code, we report good or bad */
1101 switch (bcs->Status) {
1102 case US_BULK_STAT_OK:
1103 /* device babbled -- return fake sense data */
1105 memcpy(srb->sense_buffer,
1106 usb_stor_sense_invalidCDB,
1107 sizeof(usb_stor_sense_invalidCDB));
1108 return USB_STOR_TRANSPORT_NO_SENSE;
1111 /* command good -- note that data could be short */
1112 return USB_STOR_TRANSPORT_GOOD;
1114 case US_BULK_STAT_FAIL:
1115 /* command failed */
1116 return USB_STOR_TRANSPORT_FAILED;
1118 case US_BULK_STAT_PHASE:
1119 /* phase error -- note that a transport reset will be
1120 * invoked by the invoke_transport() function
1122 return USB_STOR_TRANSPORT_ERROR;
1125 /* we should never get here, but if we do, we're in trouble */
1126 return USB_STOR_TRANSPORT_ERROR;
1129 /***********************************************************************
1131 ***********************************************************************/
1133 /* This is the common part of the device reset code.
1135 * It's handy that every transport mechanism uses the control endpoint for
1138 * Basically, we send a reset with a 5-second timeout, so we don't get
1139 * jammed attempting to do the reset.
1141 static int usb_stor_reset_common(struct us_data *us,
1142 u8 request, u8 requesttype,
1143 u16 value, u16 index, void *data, u16 size)
1148 if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
1149 US_DEBUGP("No reset during disconnect\n");
1153 result = usb_stor_control_msg(us, us->send_ctrl_pipe,
1154 request, requesttype, value, index, data, size,
1157 US_DEBUGP("Soft reset failed: %d\n", result);
1161 /* Give the device some time to recover from the reset,
1162 * but don't delay disconnect processing. */
1163 wait_event_interruptible_timeout(us->delay_wait,
1164 test_bit(US_FLIDX_DISCONNECTING, &us->flags),
1166 if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
1167 US_DEBUGP("Reset interrupted by disconnect\n");
1171 US_DEBUGP("Soft reset: clearing bulk-in endpoint halt\n");
1172 result = usb_stor_clear_halt(us, us->recv_bulk_pipe);
1174 US_DEBUGP("Soft reset: clearing bulk-out endpoint halt\n");
1175 result2 = usb_stor_clear_halt(us, us->send_bulk_pipe);
1177 /* return a result code based on the result of the clear-halts */
1181 US_DEBUGP("Soft reset failed\n");
1183 US_DEBUGP("Soft reset done\n");
1187 /* This issues a CB[I] Reset to the device in question
1189 #define CB_RESET_CMD_SIZE 12
1191 int usb_stor_CB_reset(struct us_data *us)
1193 US_DEBUGP("%s called\n", __FUNCTION__);
1195 memset(us->iobuf, 0xFF, CB_RESET_CMD_SIZE);
1196 us->iobuf[0] = SEND_DIAGNOSTIC;
1198 return usb_stor_reset_common(us, US_CBI_ADSC,
1199 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1200 0, us->ifnum, us->iobuf, CB_RESET_CMD_SIZE);
1203 /* This issues a Bulk-only Reset to the device in question, including
1204 * clearing the subsequent endpoint halts that may occur.
1206 int usb_stor_Bulk_reset(struct us_data *us)
1208 US_DEBUGP("%s called\n", __FUNCTION__);
1210 return usb_stor_reset_common(us, US_BULK_RESET_REQUEST,
1211 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1212 0, us->ifnum, NULL, 0);
1215 /* Issue a USB port reset to the device. But don't do anything if
1216 * there's more than one interface in the device, so that other users
1217 * are not affected. */
1218 int usb_stor_port_reset(struct us_data *us)
1222 if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
1224 US_DEBUGP("No reset during disconnect\n");
1225 } else if (us->pusb_dev->actconfig->desc.bNumInterfaces != 1) {
1227 US_DEBUGP("Refusing to reset a multi-interface device\n");
1230 usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
1232 US_DEBUGP("unable to lock device for reset: %d\n",
1235 result = usb_reset_device(us->pusb_dev);
1237 usb_unlock_device(us->pusb_dev);
1238 US_DEBUGP("usb_reset_device returns %d\n", result);