diff options
Diffstat (limited to 'drivers/usb/storage/transport.c')
| -rw-r--r-- | drivers/usb/storage/transport.c | 1450 |
1 files changed, 1450 insertions, 0 deletions
diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c new file mode 100644 index 000000000..7449e3790 --- /dev/null +++ b/drivers/usb/storage/transport.c @@ -0,0 +1,1450 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Driver for USB Mass Storage compliant devices + * + * Current development and maintenance by: + * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net) + * + * Developed with the assistance of: + * (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org) + * (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov) + * (c) 2002 Alan Stern <stern@rowland.org> + * + * Initial work by: + * (c) 1999 Michael Gee (michael@linuxspecific.com) + * + * This driver is based on the 'USB Mass Storage Class' document. This + * describes in detail the protocol used to communicate with such + * devices. Clearly, the designers had SCSI and ATAPI commands in + * mind when they created this document. The commands are all very + * similar to commands in the SCSI-II and ATAPI specifications. + * + * It is important to note that in a number of cases this class + * exhibits class-specific exemptions from the USB specification. + * Notably the usage of NAK, STALL and ACK differs from the norm, in + * that they are used to communicate wait, failed and OK on commands. + * + * Also, for certain devices, the interrupt endpoint is used to convey + * status of a command. + */ + +#include <linux/sched.h> +#include <linux/gfp.h> +#include <linux/errno.h> +#include <linux/export.h> + +#include <linux/usb/quirks.h> + +#include <scsi/scsi.h> +#include <scsi/scsi_eh.h> +#include <scsi/scsi_device.h> + +#include "usb.h" +#include "transport.h" +#include "protocol.h" +#include "scsiglue.h" +#include "debug.h" + +#include <linux/blkdev.h> +#include "../../scsi/sd.h" + + +/*********************************************************************** + * Data transfer routines + ***********************************************************************/ + +/* + * This is subtle, so pay attention: + * --------------------------------- + * We're very concerned about races with a command abort. Hanging this code + * is a sure fire way to hang the kernel. (Note that this discussion applies + * only to transactions resulting from a scsi queued-command, since only + * these transactions are subject to a scsi abort. Other transactions, such + * as those occurring during device-specific initialization, must be handled + * by a separate code path.) + * + * The abort function (usb_storage_command_abort() in scsiglue.c) first + * sets the machine state and the ABORTING bit in us->dflags to prevent + * new URBs from being submitted. It then calls usb_stor_stop_transport() + * below, which atomically tests-and-clears the URB_ACTIVE bit in us->dflags + * to see if the current_urb needs to be stopped. Likewise, the SG_ACTIVE + * bit is tested to see if the current_sg scatter-gather request needs to be + * stopped. The timeout callback routine does much the same thing. + * + * When a disconnect occurs, the DISCONNECTING bit in us->dflags is set to + * prevent new URBs from being submitted, and usb_stor_stop_transport() is + * called to stop any ongoing requests. + * + * The submit function first verifies that the submitting is allowed + * (neither ABORTING nor DISCONNECTING bits are set) and that the submit + * completes without errors, and only then sets the URB_ACTIVE bit. This + * prevents the stop_transport() function from trying to cancel the URB + * while the submit call is underway. Next, the submit function must test + * the flags to see if an abort or disconnect occurred during the submission + * or before the URB_ACTIVE bit was set. If so, it's essential to cancel + * the URB if it hasn't been cancelled already (i.e., if the URB_ACTIVE bit + * is still set). Either way, the function must then wait for the URB to + * finish. Note that the URB can still be in progress even after a call to + * usb_unlink_urb() returns. + * + * The idea is that (1) once the ABORTING or DISCONNECTING bit is set, + * either the stop_transport() function or the submitting function + * is guaranteed to call usb_unlink_urb() for an active URB, + * and (2) test_and_clear_bit() prevents usb_unlink_urb() from being + * called more than once or from being called during usb_submit_urb(). + */ + +/* + * This is the completion handler which will wake us up when an URB + * completes. + */ +static void usb_stor_blocking_completion(struct urb *urb) +{ + struct completion *urb_done_ptr = urb->context; + + complete(urb_done_ptr); +} + +/* + * This is the common part of the URB message submission code + * + * All URBs from the usb-storage driver involved in handling a queued scsi + * command _must_ pass through this function (or something like it) for the + * abort mechanisms to work properly. + */ +static int usb_stor_msg_common(struct us_data *us, int timeout) +{ + struct completion urb_done; + long timeleft; + int status; + + /* don't submit URBs during abort processing */ + if (test_bit(US_FLIDX_ABORTING, &us->dflags)) + return -EIO; + + /* set up data structures for the wakeup system */ + init_completion(&urb_done); + + /* fill the common fields in the URB */ + us->current_urb->context = &urb_done; + us->current_urb->transfer_flags = 0; + + /* + * we assume that if transfer_buffer isn't us->iobuf then it + * hasn't been mapped for DMA. Yes, this is clunky, but it's + * easier than always having the caller tell us whether the + * transfer buffer has already been mapped. + */ + if (us->current_urb->transfer_buffer == us->iobuf) + us->current_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + us->current_urb->transfer_dma = us->iobuf_dma; + + /* submit the URB */ + status = usb_submit_urb(us->current_urb, GFP_NOIO); + if (status) { + /* something went wrong */ + return status; + } + + /* + * since the URB has been submitted successfully, it's now okay + * to cancel it + */ + set_bit(US_FLIDX_URB_ACTIVE, &us->dflags); + + /* did an abort occur during the submission? */ + if (test_bit(US_FLIDX_ABORTING, &us->dflags)) { + + /* cancel the URB, if it hasn't been cancelled already */ + if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) { + usb_stor_dbg(us, "-- cancelling URB\n"); + usb_unlink_urb(us->current_urb); + } + } + + /* wait for the completion of the URB */ + timeleft = wait_for_completion_interruptible_timeout( + &urb_done, timeout ? : MAX_SCHEDULE_TIMEOUT); + + clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags); + + if (timeleft <= 0) { + usb_stor_dbg(us, "%s -- cancelling URB\n", + timeleft == 0 ? "Timeout" : "Signal"); + usb_kill_urb(us->current_urb); + } + + /* return the URB status */ + return us->current_urb->status; +} + +/* + * Transfer one control message, with timeouts, and allowing early + * termination. Return codes are usual -Exxx, *not* USB_STOR_XFER_xxx. + */ +int usb_stor_control_msg(struct us_data *us, unsigned int pipe, + u8 request, u8 requesttype, u16 value, u16 index, + void *data, u16 size, int timeout) +{ + int status; + + usb_stor_dbg(us, "rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n", + request, requesttype, value, index, size); + + /* fill in the devrequest structure */ + us->cr->bRequestType = requesttype; + us->cr->bRequest = request; + us->cr->wValue = cpu_to_le16(value); + us->cr->wIndex = cpu_to_le16(index); + us->cr->wLength = cpu_to_le16(size); + + /* fill and submit the URB */ + usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe, + (unsigned char*) us->cr, data, size, + usb_stor_blocking_completion, NULL); + status = usb_stor_msg_common(us, timeout); + + /* return the actual length of the data transferred if no error */ + if (status == 0) + status = us->current_urb->actual_length; + return status; +} +EXPORT_SYMBOL_GPL(usb_stor_control_msg); + +/* + * This is a version of usb_clear_halt() that allows early termination and + * doesn't read the status from the device -- this is because some devices + * crash their internal firmware when the status is requested after a halt. + * + * A definitive list of these 'bad' devices is too difficult to maintain or + * make complete enough to be useful. This problem was first observed on the + * Hagiwara FlashGate DUAL unit. However, bus traces reveal that neither + * MacOS nor Windows checks the status after clearing a halt. + * + * Since many vendors in this space limit their testing to interoperability + * with these two OSes, specification violations like this one are common. + */ +int usb_stor_clear_halt(struct us_data *us, unsigned int pipe) +{ + int result; + int endp = usb_pipeendpoint(pipe); + + if (usb_pipein (pipe)) + endp |= USB_DIR_IN; + + result = usb_stor_control_msg(us, us->send_ctrl_pipe, + USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, + USB_ENDPOINT_HALT, endp, + NULL, 0, 3*HZ); + + if (result >= 0) + usb_reset_endpoint(us->pusb_dev, endp); + + usb_stor_dbg(us, "result = %d\n", result); + return result; +} +EXPORT_SYMBOL_GPL(usb_stor_clear_halt); + + +/* + * Interpret the results of a URB transfer + * + * This function prints appropriate debugging messages, clears halts on + * non-control endpoints, and translates the status to the corresponding + * USB_STOR_XFER_xxx return code. + */ +static int interpret_urb_result(struct us_data *us, unsigned int pipe, + unsigned int length, int result, unsigned int partial) +{ + usb_stor_dbg(us, "Status code %d; transferred %u/%u\n", + result, partial, length); + switch (result) { + + /* no error code; did we send all the data? */ + case 0: + if (partial != length) { + usb_stor_dbg(us, "-- short transfer\n"); + return USB_STOR_XFER_SHORT; + } + + usb_stor_dbg(us, "-- transfer complete\n"); + return USB_STOR_XFER_GOOD; + + /* stalled */ + case -EPIPE: + /* + * for control endpoints, (used by CB[I]) a stall indicates + * a failed command + */ + if (usb_pipecontrol(pipe)) { + usb_stor_dbg(us, "-- stall on control pipe\n"); + return USB_STOR_XFER_STALLED; + } + + /* for other sorts of endpoint, clear the stall */ + usb_stor_dbg(us, "clearing endpoint halt for pipe 0x%x\n", + pipe); + if (usb_stor_clear_halt(us, pipe) < 0) + return USB_STOR_XFER_ERROR; + return USB_STOR_XFER_STALLED; + + /* babble - the device tried to send more than we wanted to read */ + case -EOVERFLOW: + usb_stor_dbg(us, "-- babble\n"); + return USB_STOR_XFER_LONG; + + /* the transfer was cancelled by abort, disconnect, or timeout */ + case -ECONNRESET: + usb_stor_dbg(us, "-- transfer cancelled\n"); + return USB_STOR_XFER_ERROR; + + /* short scatter-gather read transfer */ + case -EREMOTEIO: + usb_stor_dbg(us, "-- short read transfer\n"); + return USB_STOR_XFER_SHORT; + + /* abort or disconnect in progress */ + case -EIO: + usb_stor_dbg(us, "-- abort or disconnect in progress\n"); + return USB_STOR_XFER_ERROR; + + /* the catch-all error case */ + default: + usb_stor_dbg(us, "-- unknown error\n"); + return USB_STOR_XFER_ERROR; + } +} + +/* + * Transfer one control message, without timeouts, but allowing early + * termination. Return codes are USB_STOR_XFER_xxx. + */ +int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe, + u8 request, u8 requesttype, u16 value, u16 index, + void *data, u16 size) +{ + int result; + + usb_stor_dbg(us, "rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n", + request, requesttype, value, index, size); + + /* fill in the devrequest structure */ + us->cr->bRequestType = requesttype; + us->cr->bRequest = request; + us->cr->wValue = cpu_to_le16(value); + us->cr->wIndex = cpu_to_le16(index); + us->cr->wLength = cpu_to_le16(size); + + /* fill and submit the URB */ + usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe, + (unsigned char*) us->cr, data, size, + usb_stor_blocking_completion, NULL); + result = usb_stor_msg_common(us, 0); + + return interpret_urb_result(us, pipe, size, result, + us->current_urb->actual_length); +} +EXPORT_SYMBOL_GPL(usb_stor_ctrl_transfer); + +/* + * Receive one interrupt buffer, without timeouts, but allowing early + * termination. Return codes are USB_STOR_XFER_xxx. + * + * This routine always uses us->recv_intr_pipe as the pipe and + * us->ep_bInterval as the interrupt interval. + */ +static int usb_stor_intr_transfer(struct us_data *us, void *buf, + unsigned int length) +{ + int result; + unsigned int pipe = us->recv_intr_pipe; + unsigned int maxp; + + usb_stor_dbg(us, "xfer %u bytes\n", length); + + /* calculate the max packet size */ + maxp = usb_maxpacket(us->pusb_dev, pipe); + if (maxp > length) + maxp = length; + + /* fill and submit the URB */ + usb_fill_int_urb(us->current_urb, us->pusb_dev, pipe, buf, + maxp, usb_stor_blocking_completion, NULL, + us->ep_bInterval); + result = usb_stor_msg_common(us, 0); + + return interpret_urb_result(us, pipe, length, result, + us->current_urb->actual_length); +} + +/* + * Transfer one buffer via bulk pipe, without timeouts, but allowing early + * termination. Return codes are USB_STOR_XFER_xxx. If the bulk pipe + * stalls during the transfer, the halt is automatically cleared. + */ +int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe, + void *buf, unsigned int length, unsigned int *act_len) +{ + int result; + + usb_stor_dbg(us, "xfer %u bytes\n", length); + + /* fill and submit the URB */ + usb_fill_bulk_urb(us->current_urb, us->pusb_dev, pipe, buf, length, + usb_stor_blocking_completion, NULL); + result = usb_stor_msg_common(us, 0); + + /* store the actual length of the data transferred */ + if (act_len) + *act_len = us->current_urb->actual_length; + return interpret_urb_result(us, pipe, length, result, + us->current_urb->actual_length); +} +EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_buf); + +/* + * Transfer a scatter-gather list via bulk transfer + * + * This function does basically the same thing as usb_stor_bulk_transfer_buf() + * above, but it uses the usbcore scatter-gather library. + */ +static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe, + struct scatterlist *sg, int num_sg, unsigned int length, + unsigned int *act_len) +{ + int result; + + /* don't submit s-g requests during abort processing */ + if (test_bit(US_FLIDX_ABORTING, &us->dflags)) + goto usb_stor_xfer_error; + + /* initialize the scatter-gather request block */ + usb_stor_dbg(us, "xfer %u bytes, %d entries\n", length, num_sg); + result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0, + sg, num_sg, length, GFP_NOIO); + if (result) { + usb_stor_dbg(us, "usb_sg_init returned %d\n", result); + goto usb_stor_xfer_error; + } + + /* + * since the block has been initialized successfully, it's now + * okay to cancel it + */ + set_bit(US_FLIDX_SG_ACTIVE, &us->dflags); + + /* did an abort occur during the submission? */ + if (test_bit(US_FLIDX_ABORTING, &us->dflags)) { + + /* cancel the request, if it hasn't been cancelled already */ + if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) { + usb_stor_dbg(us, "-- cancelling sg request\n"); + usb_sg_cancel(&us->current_sg); + } + } + + /* wait for the completion of the transfer */ + usb_sg_wait(&us->current_sg); + clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags); + + result = us->current_sg.status; + if (act_len) + *act_len = us->current_sg.bytes; + return interpret_urb_result(us, pipe, length, result, + us->current_sg.bytes); + +usb_stor_xfer_error: + if (act_len) + *act_len = 0; + return USB_STOR_XFER_ERROR; +} + +/* + * Common used function. Transfer a complete command + * via usb_stor_bulk_transfer_sglist() above. Set cmnd resid + */ +int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe, + struct scsi_cmnd* srb) +{ + unsigned int partial; + int result = usb_stor_bulk_transfer_sglist(us, pipe, scsi_sglist(srb), + scsi_sg_count(srb), scsi_bufflen(srb), + &partial); + + scsi_set_resid(srb, scsi_bufflen(srb) - partial); + return result; +} +EXPORT_SYMBOL_GPL(usb_stor_bulk_srb); + +/* + * Transfer an entire SCSI command's worth of data payload over the bulk + * pipe. + * + * Note that this uses usb_stor_bulk_transfer_buf() and + * usb_stor_bulk_transfer_sglist() to achieve its goals -- + * this function simply determines whether we're going to use + * scatter-gather or not, and acts appropriately. + */ +int usb_stor_bulk_transfer_sg(struct us_data* us, unsigned int pipe, + void *buf, unsigned int length_left, int use_sg, int *residual) +{ + int result; + unsigned int partial; + + /* are we scatter-gathering? */ + if (use_sg) { + /* use the usb core scatter-gather primitives */ + result = usb_stor_bulk_transfer_sglist(us, pipe, + (struct scatterlist *) buf, use_sg, + length_left, &partial); + length_left -= partial; + } else { + /* no scatter-gather, just make the request */ + result = usb_stor_bulk_transfer_buf(us, pipe, buf, + length_left, &partial); + length_left -= partial; + } + + /* store the residual and return the error code */ + if (residual) + *residual = length_left; + return result; +} +EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_sg); + +/*********************************************************************** + * Transport routines + ***********************************************************************/ + +/* + * There are so many devices that report the capacity incorrectly, + * this routine was written to counteract some of the resulting + * problems. + */ +static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb) +{ + struct gendisk *disk; + struct scsi_disk *sdkp; + u32 sector; + + /* To Report "Medium Error: Record Not Found */ + static unsigned char record_not_found[18] = { + [0] = 0x70, /* current error */ + [2] = MEDIUM_ERROR, /* = 0x03 */ + [7] = 0x0a, /* additional length */ + [12] = 0x14 /* Record Not Found */ + }; + + /* + * If last-sector problems can't occur, whether because the + * capacity was already decremented or because the device is + * known to report the correct capacity, then we don't need + * to do anything. + */ + if (!us->use_last_sector_hacks) + return; + + /* Was this command a READ(10) or a WRITE(10)? */ + if (srb->cmnd[0] != READ_10 && srb->cmnd[0] != WRITE_10) + goto done; + + /* Did this command access the last sector? */ + sector = (srb->cmnd[2] << 24) | (srb->cmnd[3] << 16) | + (srb->cmnd[4] << 8) | (srb->cmnd[5]); + disk = scsi_cmd_to_rq(srb)->q->disk; + if (!disk) + goto done; + sdkp = scsi_disk(disk); + if (!sdkp) + goto done; + if (sector + 1 != sdkp->capacity) + goto done; + + if (srb->result == SAM_STAT_GOOD && scsi_get_resid(srb) == 0) { + + /* + * The command succeeded. We know this device doesn't + * have the last-sector bug, so stop checking it. + */ + us->use_last_sector_hacks = 0; + + } else { + /* + * The command failed. Allow up to 3 retries in case this + * is some normal sort of failure. After that, assume the + * capacity is wrong and we're trying to access the sector + * beyond the end. Replace the result code and sense data + * with values that will cause the SCSI core to fail the + * command immediately, instead of going into an infinite + * (or even just a very long) retry loop. + */ + if (++us->last_sector_retries < 3) + return; + srb->result = SAM_STAT_CHECK_CONDITION; + memcpy(srb->sense_buffer, record_not_found, + sizeof(record_not_found)); + } + + done: + /* + * Don't reset the retry counter for TEST UNIT READY commands, + * because they get issued after device resets which might be + * caused by a failed last-sector access. + */ + if (srb->cmnd[0] != TEST_UNIT_READY) + us->last_sector_retries = 0; +} + +/* + * Invoke the transport and basic error-handling/recovery methods + * + * This is used by the protocol layers to actually send the message to + * the device and receive the response. + */ +void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) +{ + int need_auto_sense; + int result; + + /* send the command to the transport layer */ + scsi_set_resid(srb, 0); + result = us->transport(srb, us); + + /* + * if the command gets aborted by the higher layers, we need to + * short-circuit all other processing + */ + if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) { + usb_stor_dbg(us, "-- command was aborted\n"); + srb->result = DID_ABORT << 16; + goto Handle_Errors; + } + + /* if there is a transport error, reset and don't auto-sense */ + if (result == USB_STOR_TRANSPORT_ERROR) { + usb_stor_dbg(us, "-- transport indicates error, resetting\n"); + srb->result = DID_ERROR << 16; + goto Handle_Errors; + } + + /* if the transport provided its own sense data, don't auto-sense */ + if (result == USB_STOR_TRANSPORT_NO_SENSE) { + srb->result = SAM_STAT_CHECK_CONDITION; + last_sector_hacks(us, srb); + return; + } + + srb->result = SAM_STAT_GOOD; + + /* + * Determine if we need to auto-sense + * + * I normally don't use a flag like this, but it's almost impossible + * to understand what's going on here if I don't. + */ + need_auto_sense = 0; + + /* + * If we're running the CB transport, which is incapable + * of determining status on its own, we will auto-sense + * unless the operation involved a data-in transfer. Devices + * can signal most data-in errors by stalling the bulk-in pipe. + */ + if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_DPCM_USB) && + srb->sc_data_direction != DMA_FROM_DEVICE) { + usb_stor_dbg(us, "-- CB transport device requiring auto-sense\n"); + need_auto_sense = 1; + } + + /* Some devices (Kindle) require another command after SYNC CACHE */ + if ((us->fflags & US_FL_SENSE_AFTER_SYNC) && + srb->cmnd[0] == SYNCHRONIZE_CACHE) { + usb_stor_dbg(us, "-- sense after SYNC CACHE\n"); + need_auto_sense = 1; + } + + /* + * If we have a failure, we're going to do a REQUEST_SENSE + * automatically. Note that we differentiate between a command + * "failure" and an "error" in the transport mechanism. + */ + if (result == USB_STOR_TRANSPORT_FAILED) { + usb_stor_dbg(us, "-- transport indicates command failure\n"); + need_auto_sense = 1; + } + + /* + * Determine if this device is SAT by seeing if the + * command executed successfully. Otherwise we'll have + * to wait for at least one CHECK_CONDITION to determine + * SANE_SENSE support + */ + if (unlikely((srb->cmnd[0] == ATA_16 || srb->cmnd[0] == ATA_12) && + result == USB_STOR_TRANSPORT_GOOD && + !(us->fflags & US_FL_SANE_SENSE) && + !(us->fflags & US_FL_BAD_SENSE) && + !(srb->cmnd[2] & 0x20))) { + usb_stor_dbg(us, "-- SAT supported, increasing auto-sense\n"); + us->fflags |= US_FL_SANE_SENSE; + } + + /* + * A short transfer on a command where we don't expect it + * is unusual, but it doesn't mean we need to auto-sense. + */ + if ((scsi_get_resid(srb) > 0) && + !((srb->cmnd[0] == REQUEST_SENSE) || + (srb->cmnd[0] == INQUIRY) || + (srb->cmnd[0] == MODE_SENSE) || + (srb->cmnd[0] == LOG_SENSE) || + (srb->cmnd[0] == MODE_SENSE_10))) { + usb_stor_dbg(us, "-- unexpectedly short transfer\n"); + } + + /* Now, if we need to do the auto-sense, let's do it */ + if (need_auto_sense) { + int temp_result; + struct scsi_eh_save ses; + int sense_size = US_SENSE_SIZE; + struct scsi_sense_hdr sshdr; + const u8 *scdd; + u8 fm_ili; + + /* device supports and needs bigger sense buffer */ + if (us->fflags & US_FL_SANE_SENSE) + sense_size = ~0; +Retry_Sense: + usb_stor_dbg(us, "Issuing auto-REQUEST_SENSE\n"); + + scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sense_size); + + /* FIXME: we must do the protocol translation here */ + if (us->subclass == USB_SC_RBC || us->subclass == USB_SC_SCSI || + us->subclass == USB_SC_CYP_ATACB) + srb->cmd_len = 6; + else + srb->cmd_len = 12; + + /* issue the auto-sense command */ + scsi_set_resid(srb, 0); + temp_result = us->transport(us->srb, us); + + /* let's clean up right away */ + scsi_eh_restore_cmnd(srb, &ses); + + if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) { + usb_stor_dbg(us, "-- auto-sense aborted\n"); + srb->result = DID_ABORT << 16; + + /* If SANE_SENSE caused this problem, disable it */ + if (sense_size != US_SENSE_SIZE) { + us->fflags &= ~US_FL_SANE_SENSE; + us->fflags |= US_FL_BAD_SENSE; + } + goto Handle_Errors; + } + + /* + * Some devices claim to support larger sense but fail when + * trying to request it. When a transport failure happens + * using US_FS_SANE_SENSE, we always retry with a standard + * (small) sense request. This fixes some USB GSM modems + */ + if (temp_result == USB_STOR_TRANSPORT_FAILED && + sense_size != US_SENSE_SIZE) { + usb_stor_dbg(us, "-- auto-sense failure, retry small sense\n"); + sense_size = US_SENSE_SIZE; + us->fflags &= ~US_FL_SANE_SENSE; + us->fflags |= US_FL_BAD_SENSE; + goto Retry_Sense; + } + + /* Other failures */ + if (temp_result != USB_STOR_TRANSPORT_GOOD) { + usb_stor_dbg(us, "-- auto-sense failure\n"); + + /* + * we skip the reset if this happens to be a + * multi-target device, since failure of an + * auto-sense is perfectly valid + */ + srb->result = DID_ERROR << 16; + if (!(us->fflags & US_FL_SCM_MULT_TARG)) + goto Handle_Errors; + return; + } + + /* + * If the sense data returned is larger than 18-bytes then we + * assume this device supports requesting more in the future. + * The response code must be 70h through 73h inclusive. + */ + if (srb->sense_buffer[7] > (US_SENSE_SIZE - 8) && + !(us->fflags & US_FL_SANE_SENSE) && + !(us->fflags & US_FL_BAD_SENSE) && + (srb->sense_buffer[0] & 0x7C) == 0x70) { + usb_stor_dbg(us, "-- SANE_SENSE support enabled\n"); + us->fflags |= US_FL_SANE_SENSE; + + /* + * Indicate to the user that we truncated their sense + * because we didn't know it supported larger sense. + */ + usb_stor_dbg(us, "-- Sense data truncated to %i from %i\n", + US_SENSE_SIZE, + srb->sense_buffer[7] + 8); + srb->sense_buffer[7] = (US_SENSE_SIZE - 8); + } + + scsi_normalize_sense(srb->sense_buffer, SCSI_SENSE_BUFFERSIZE, + &sshdr); + + usb_stor_dbg(us, "-- Result from auto-sense is %d\n", + temp_result); + usb_stor_dbg(us, "-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n", + sshdr.response_code, sshdr.sense_key, + sshdr.asc, sshdr.ascq); +#ifdef CONFIG_USB_STORAGE_DEBUG + usb_stor_show_sense(us, sshdr.sense_key, sshdr.asc, sshdr.ascq); +#endif + + /* set the result so the higher layers expect this data */ + srb->result = SAM_STAT_CHECK_CONDITION; + + scdd = scsi_sense_desc_find(srb->sense_buffer, + SCSI_SENSE_BUFFERSIZE, 4); + fm_ili = (scdd ? scdd[3] : srb->sense_buffer[2]) & 0xA0; + + /* + * We often get empty sense data. This could indicate that + * everything worked or that there was an unspecified + * problem. We have to decide which. + */ + if (sshdr.sense_key == 0 && sshdr.asc == 0 && sshdr.ascq == 0 && + fm_ili == 0) { + /* + * If things are really okay, then let's show that. + * Zero out the sense buffer so the higher layers + * won't realize we did an unsolicited auto-sense. + */ + if (result == USB_STOR_TRANSPORT_GOOD) { + srb->result = SAM_STAT_GOOD; + srb->sense_buffer[0] = 0x0; + } + + /* + * ATA-passthru commands use sense data to report + * the command completion status, and often devices + * return Check Condition status when nothing is + * wrong. + */ + else if (srb->cmnd[0] == ATA_16 || + srb->cmnd[0] == ATA_12) { + /* leave the data alone */ + } + + /* + * If there was a problem, report an unspecified + * hardware error to prevent the higher layers from + * entering an infinite retry loop. + */ + else { + srb->result = DID_ERROR << 16; + if ((sshdr.response_code & 0x72) == 0x72) + srb->sense_buffer[1] = HARDWARE_ERROR; + else + srb->sense_buffer[2] = HARDWARE_ERROR; + } + } + } + + /* + * Some devices don't work or return incorrect data the first + * time they get a READ(10) command, or for the first READ(10) + * after a media change. If the INITIAL_READ10 flag is set, + * keep track of whether READ(10) commands succeed. If the + * previous one succeeded and this one failed, set the REDO_READ10 + * flag to force a retry. + */ + if (unlikely((us->fflags & US_FL_INITIAL_READ10) && + srb->cmnd[0] == READ_10)) { + if (srb->result == SAM_STAT_GOOD) { + set_bit(US_FLIDX_READ10_WORKED, &us->dflags); + } else if (test_bit(US_FLIDX_READ10_WORKED, &us->dflags)) { + clear_bit(US_FLIDX_READ10_WORKED, &us->dflags); + set_bit(US_FLIDX_REDO_READ10, &us->dflags); + } + + /* + * Next, if the REDO_READ10 flag is set, return a result + * code that will cause the SCSI core to retry the READ(10) + * command immediately. + */ + if (test_bit(US_FLIDX_REDO_READ10, &us->dflags)) { + clear_bit(US_FLIDX_REDO_READ10, &us->dflags); + srb->result = DID_IMM_RETRY << 16; + srb->sense_buffer[0] = 0; + } + } + + /* Did we transfer less than the minimum amount required? */ + if ((srb->result == SAM_STAT_GOOD || srb->sense_buffer[2] == 0) && + scsi_bufflen(srb) - scsi_get_resid(srb) < srb->underflow) + srb->result = DID_ERROR << 16; + + last_sector_hacks(us, srb); + return; + + /* + * Error and abort processing: try to resynchronize with the device + * by issuing a port reset. If that fails, try a class-specific + * device reset. + */ + Handle_Errors: + + /* + * Set the RESETTING bit, and clear the ABORTING bit so that + * the reset may proceed. + */ + scsi_lock(us_to_host(us)); + set_bit(US_FLIDX_RESETTING, &us->dflags); + clear_bit(US_FLIDX_ABORTING, &us->dflags); + scsi_unlock(us_to_host(us)); + + /* + * We must release the device lock because the pre_reset routine + * will want to acquire it. + */ + mutex_unlock(&us->dev_mutex); + result = usb_stor_port_reset(us); + mutex_lock(&us->dev_mutex); + + if (result < 0) { + scsi_lock(us_to_host(us)); + usb_stor_report_device_reset(us); + scsi_unlock(us_to_host(us)); + us->transport_reset(us); + } + clear_bit(US_FLIDX_RESETTING, &us->dflags); + last_sector_hacks(us, srb); +} + +/* Stop the current URB transfer */ +void usb_stor_stop_transport(struct us_data *us) +{ + /* + * If the state machine is blocked waiting for an URB, + * let's wake it up. The test_and_clear_bit() call + * guarantees that if a URB has just been submitted, + * it won't be cancelled more than once. + */ + if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) { + usb_stor_dbg(us, "-- cancelling URB\n"); + usb_unlink_urb(us->current_urb); + } + + /* If we are waiting for a scatter-gather operation, cancel it. */ + if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) { + usb_stor_dbg(us, "-- cancelling sg request\n"); + usb_sg_cancel(&us->current_sg); + } +} + +/* + * Control/Bulk and Control/Bulk/Interrupt transport + */ + +int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) +{ + unsigned int transfer_length = scsi_bufflen(srb); + unsigned int pipe = 0; + int result; + + /* COMMAND STAGE */ + /* let's send the command via the control pipe */ + /* + * Command is sometime (f.e. after scsi_eh_prep_cmnd) on the stack. + * Stack may be vmallocated. So no DMA for us. Make a copy. + */ + memcpy(us->iobuf, srb->cmnd, srb->cmd_len); + result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe, + US_CBI_ADSC, + USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, + us->ifnum, us->iobuf, srb->cmd_len); + + /* check the return code for the command */ + usb_stor_dbg(us, "Call to usb_stor_ctrl_transfer() returned %d\n", + result); + + /* if we stalled the command, it means command failed */ + if (result == USB_STOR_XFER_STALLED) { + return USB_STOR_TRANSPORT_FAILED; + } + + /* Uh oh... serious problem here */ + if (result != USB_STOR_XFER_GOOD) { + return USB_STOR_TRANSPORT_ERROR; + } + + /* DATA STAGE */ + /* transfer the data payload for this command, if one exists*/ + if (transfer_length) { + pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? + us->recv_bulk_pipe : us->send_bulk_pipe; + result = usb_stor_bulk_srb(us, pipe, srb); + usb_stor_dbg(us, "CBI data stage result is 0x%x\n", result); + + /* if we stalled the data transfer it means command failed */ + if (result == USB_STOR_XFER_STALLED) + return USB_STOR_TRANSPORT_FAILED; + if (result > USB_STOR_XFER_STALLED) + return USB_STOR_TRANSPORT_ERROR; + } + + /* STATUS STAGE */ + + /* + * NOTE: CB does not have a status stage. Silly, I know. So + * we have to catch this at a higher level. + */ + if (us->protocol != USB_PR_CBI) + return USB_STOR_TRANSPORT_GOOD; + + result = usb_stor_intr_transfer(us, us->iobuf, 2); + usb_stor_dbg(us, "Got interrupt data (0x%x, 0x%x)\n", + us->iobuf[0], us->iobuf[1]); + if (result != USB_STOR_XFER_GOOD) + return USB_STOR_TRANSPORT_ERROR; + + /* + * UFI gives us ASC and ASCQ, like a request sense + * + * REQUEST_SENSE and INQUIRY don't affect the sense data on UFI + * devices, so we ignore the information for those commands. Note + * that this means we could be ignoring a real error on these + * commands, but that can't be helped. + */ + if (us->subclass == USB_SC_UFI) { + if (srb->cmnd[0] == REQUEST_SENSE || + srb->cmnd[0] == INQUIRY) + return USB_STOR_TRANSPORT_GOOD; + if (us->iobuf[0]) + goto Failed; + return USB_STOR_TRANSPORT_GOOD; + } + + /* + * If not UFI, we interpret the data as a result code + * The first byte should always be a 0x0. + * + * Some bogus devices don't follow that rule. They stuff the ASC + * into the first byte -- so if it's non-zero, call it a failure. + */ + if (us->iobuf[0]) { + usb_stor_dbg(us, "CBI IRQ data showed reserved bType 0x%x\n", + us->iobuf[0]); + goto Failed; + + } + + /* The second byte & 0x0F should be 0x0 for good, otherwise error */ + switch (us->iobuf[1] & 0x0F) { + case 0x00: + return USB_STOR_TRANSPORT_GOOD; + case 0x01: + goto Failed; + } + return USB_STOR_TRANSPORT_ERROR; + + /* + * the CBI spec requires that the bulk pipe must be cleared + * following any data-in/out command failure (section 2.4.3.1.3) + */ + Failed: + if (pipe) + usb_stor_clear_halt(us, pipe); + return USB_STOR_TRANSPORT_FAILED; +} +EXPORT_SYMBOL_GPL(usb_stor_CB_transport); + +/* + * Bulk only transport + */ + +/* Determine what the maximum LUN supported is */ +int usb_stor_Bulk_max_lun(struct us_data *us) +{ + int result; + + /* issue the command */ + us->iobuf[0] = 0; + result = usb_stor_control_msg(us, us->recv_ctrl_pipe, + US_BULK_GET_MAX_LUN, + USB_DIR_IN | USB_TYPE_CLASS | + USB_RECIP_INTERFACE, + 0, us->ifnum, us->iobuf, 1, 10*HZ); + + usb_stor_dbg(us, "GetMaxLUN command result is %d, data is %d\n", + result, us->iobuf[0]); + + /* + * If we have a successful request, return the result if valid. The + * CBW LUN field is 4 bits wide, so the value reported by the device + * should fit into that. + */ + if (result > 0) { + if (us->iobuf[0] < 16) { + return us->iobuf[0]; + } else { + dev_info(&us->pusb_intf->dev, + "Max LUN %d is not valid, using 0 instead", + us->iobuf[0]); + } + } + + /* + * Some devices don't like GetMaxLUN. They may STALL the control + * pipe, they may return a zero-length result, they may do nothing at + * all and timeout, or they may fail in even more bizarrely creative + * ways. In these cases the best approach is to use the default + * value: only one LUN. + */ + return 0; +} + +int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) +{ + struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf; + struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf; + unsigned int transfer_length = scsi_bufflen(srb); + unsigned int residue; + int result; + int fake_sense = 0; + unsigned int cswlen; + unsigned int cbwlen = US_BULK_CB_WRAP_LEN; + + /* Take care of BULK32 devices; set extra byte to 0 */ + if (unlikely(us->fflags & US_FL_BULK32)) { + cbwlen = 32; + us->iobuf[31] = 0; + } + + /* set up the command wrapper */ + bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN); + bcb->DataTransferLength = cpu_to_le32(transfer_length); + bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ? + US_BULK_FLAG_IN : 0; + bcb->Tag = ++us->tag; + bcb->Lun = srb->device->lun; + if (us->fflags & US_FL_SCM_MULT_TARG) + bcb->Lun |= srb->device->id << 4; + bcb->Length = srb->cmd_len; + + /* copy the command payload */ + memset(bcb->CDB, 0, sizeof(bcb->CDB)); + memcpy(bcb->CDB, srb->cmnd, bcb->Length); + + /* send it to out endpoint */ + usb_stor_dbg(us, "Bulk Command S 0x%x T 0x%x L %d F %d Trg %d LUN %d CL %d\n", + le32_to_cpu(bcb->Signature), bcb->Tag, + le32_to_cpu(bcb->DataTransferLength), bcb->Flags, + (bcb->Lun >> 4), (bcb->Lun & 0x0F), + bcb->Length); + result = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe, + bcb, cbwlen, NULL); + usb_stor_dbg(us, "Bulk command transfer result=%d\n", result); + if (result != USB_STOR_XFER_GOOD) + return USB_STOR_TRANSPORT_ERROR; + + /* DATA STAGE */ + /* send/receive data payload, if there is any */ + + /* + * Some USB-IDE converter chips need a 100us delay between the + * command phase and the data phase. Some devices need a little + * more than that, probably because of clock rate inaccuracies. + */ + if (unlikely(us->fflags & US_FL_GO_SLOW)) + usleep_range(125, 150); + + if (transfer_length) { + unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? + us->recv_bulk_pipe : us->send_bulk_pipe; + result = usb_stor_bulk_srb(us, pipe, srb); + usb_stor_dbg(us, "Bulk data transfer result 0x%x\n", result); + if (result == USB_STOR_XFER_ERROR) + return USB_STOR_TRANSPORT_ERROR; + + /* + * If the device tried to send back more data than the + * amount requested, the spec requires us to transfer + * the CSW anyway. Since there's no point retrying + * the command, we'll return fake sense data indicating + * Illegal Request, Invalid Field in CDB. + */ + if (result == USB_STOR_XFER_LONG) + fake_sense = 1; + + /* + * Sometimes a device will mistakenly skip the data phase + * and go directly to the status phase without sending a + * zero-length packet. If we get a 13-byte response here, + * check whether it really is a CSW. + */ + if (result == USB_STOR_XFER_SHORT && + srb->sc_data_direction == DMA_FROM_DEVICE && + transfer_length - scsi_get_resid(srb) == + US_BULK_CS_WRAP_LEN) { + struct scatterlist *sg = NULL; + unsigned int offset = 0; + + if (usb_stor_access_xfer_buf((unsigned char *) bcs, + US_BULK_CS_WRAP_LEN, srb, &sg, + &offset, FROM_XFER_BUF) == + US_BULK_CS_WRAP_LEN && + bcs->Signature == + cpu_to_le32(US_BULK_CS_SIGN)) { + usb_stor_dbg(us, "Device skipped data phase\n"); + scsi_set_resid(srb, transfer_length); + goto skipped_data_phase; + } + } + } + + /* + * See flow chart on pg 15 of the Bulk Only Transport spec for + * an explanation of how this code works. + */ + + /* get CSW for device status */ + usb_stor_dbg(us, "Attempting to get CSW...\n"); + result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe, + bcs, US_BULK_CS_WRAP_LEN, &cswlen); + + /* + * Some broken devices add unnecessary zero-length packets to the + * end of their data transfers. Such packets show up as 0-length + * CSWs. If we encounter such a thing, try to read the CSW again. + */ + if (result == USB_STOR_XFER_SHORT && cswlen == 0) { + usb_stor_dbg(us, "Received 0-length CSW; retrying...\n"); + result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe, + bcs, US_BULK_CS_WRAP_LEN, &cswlen); + } + + /* did the attempt to read the CSW fail? */ + if (result == USB_STOR_XFER_STALLED) { + + /* get the status again */ + usb_stor_dbg(us, "Attempting to get CSW (2nd try)...\n"); + result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe, + bcs, US_BULK_CS_WRAP_LEN, NULL); + } + + /* if we still have a failure at this point, we're in trouble */ + usb_stor_dbg(us, "Bulk status result = %d\n", result); + if (result != USB_STOR_XFER_GOOD) + return USB_STOR_TRANSPORT_ERROR; + + skipped_data_phase: + /* check bulk status */ + residue = le32_to_cpu(bcs->Residue); + usb_stor_dbg(us, "Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n", + le32_to_cpu(bcs->Signature), bcs->Tag, + residue, bcs->Status); + if (!(bcs->Tag == us->tag || (us->fflags & US_FL_BULK_IGNORE_TAG)) || + bcs->Status > US_BULK_STAT_PHASE) { + usb_stor_dbg(us, "Bulk logical error\n"); + return USB_STOR_TRANSPORT_ERROR; + } + + /* + * Some broken devices report odd signatures, so we do not check them + * for validity against the spec. We store the first one we see, + * and check subsequent transfers for validity against this signature. + */ + if (!us->bcs_signature) { + us->bcs_signature = bcs->Signature; + if (us->bcs_signature != cpu_to_le32(US_BULK_CS_SIGN)) + usb_stor_dbg(us, "Learnt BCS signature 0x%08X\n", + le32_to_cpu(us->bcs_signature)); + } else if (bcs->Signature != us->bcs_signature) { + usb_stor_dbg(us, "Signature mismatch: got %08X, expecting %08X\n", + le32_to_cpu(bcs->Signature), + le32_to_cpu(us->bcs_signature)); + return USB_STOR_TRANSPORT_ERROR; + } + + /* + * try to compute the actual residue, based on how much data + * was really transferred and what the device tells us + */ + if (residue && !(us->fflags & US_FL_IGNORE_RESIDUE)) { + + /* + * Heuristically detect devices that generate bogus residues + * by seeing what happens with INQUIRY and READ CAPACITY + * commands. + */ + if (bcs->Status == US_BULK_STAT_OK && + scsi_get_resid(srb) == 0 && + ((srb->cmnd[0] == INQUIRY && + transfer_length == 36) || + (srb->cmnd[0] == READ_CAPACITY && + transfer_length == 8))) { + us->fflags |= US_FL_IGNORE_RESIDUE; + + } else { + residue = min(residue, transfer_length); + scsi_set_resid(srb, max(scsi_get_resid(srb), residue)); + } + } + + /* based on the status code, we report good or bad */ + switch (bcs->Status) { + case US_BULK_STAT_OK: + /* device babbled -- return fake sense data */ + if (fake_sense) { + memcpy(srb->sense_buffer, + usb_stor_sense_invalidCDB, + sizeof(usb_stor_sense_invalidCDB)); + return USB_STOR_TRANSPORT_NO_SENSE; + } + + /* command good -- note that data could be short */ + return USB_STOR_TRANSPORT_GOOD; + + case US_BULK_STAT_FAIL: + /* command failed */ + return USB_STOR_TRANSPORT_FAILED; + + case US_BULK_STAT_PHASE: + /* + * phase error -- note that a transport reset will be + * invoked by the invoke_transport() function + */ + return USB_STOR_TRANSPORT_ERROR; + } + + /* we should never get here, but if we do, we're in trouble */ + return USB_STOR_TRANSPORT_ERROR; +} +EXPORT_SYMBOL_GPL(usb_stor_Bulk_transport); + +/*********************************************************************** + * Reset routines + ***********************************************************************/ + +/* + * This is the common part of the device reset code. + * + * It's handy that every transport mechanism uses the control endpoint for + * resets. + * + * Basically, we send a reset with a 5-second timeout, so we don't get + * jammed attempting to do the reset. + */ +static int usb_stor_reset_common(struct us_data *us, + u8 request, u8 requesttype, + u16 value, u16 index, void *data, u16 size) +{ + int result; + int result2; + + if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) { + usb_stor_dbg(us, "No reset during disconnect\n"); + return -EIO; + } + + result = usb_stor_control_msg(us, us->send_ctrl_pipe, + request, requesttype, value, index, data, size, + 5*HZ); + if (result < 0) { + usb_stor_dbg(us, "Soft reset failed: %d\n", result); + return result; + } + + /* + * Give the device some time to recover from the reset, + * but don't delay disconnect processing. + */ + wait_event_interruptible_timeout(us->delay_wait, + test_bit(US_FLIDX_DISCONNECTING, &us->dflags), + HZ*6); + if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) { + usb_stor_dbg(us, "Reset interrupted by disconnect\n"); + return -EIO; + } + + usb_stor_dbg(us, "Soft reset: clearing bulk-in endpoint halt\n"); + result = usb_stor_clear_halt(us, us->recv_bulk_pipe); + + usb_stor_dbg(us, "Soft reset: clearing bulk-out endpoint halt\n"); + result2 = usb_stor_clear_halt(us, us->send_bulk_pipe); + + /* return a result code based on the result of the clear-halts */ + if (result >= 0) + result = result2; + if (result < 0) + usb_stor_dbg(us, "Soft reset failed\n"); + else + usb_stor_dbg(us, "Soft reset done\n"); + return result; +} + +/* This issues a CB[I] Reset to the device in question */ +#define CB_RESET_CMD_SIZE 12 + +int usb_stor_CB_reset(struct us_data *us) +{ + memset(us->iobuf, 0xFF, CB_RESET_CMD_SIZE); + us->iobuf[0] = SEND_DIAGNOSTIC; + us->iobuf[1] = 4; + return usb_stor_reset_common(us, US_CBI_ADSC, + USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, us->ifnum, us->iobuf, CB_RESET_CMD_SIZE); +} +EXPORT_SYMBOL_GPL(usb_stor_CB_reset); + +/* + * This issues a Bulk-only Reset to the device in question, including + * clearing the subsequent endpoint halts that may occur. + */ +int usb_stor_Bulk_reset(struct us_data *us) +{ + return usb_stor_reset_common(us, US_BULK_RESET_REQUEST, + USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, us->ifnum, NULL, 0); +} +EXPORT_SYMBOL_GPL(usb_stor_Bulk_reset); + +/* + * Issue a USB port reset to the device. The caller must not hold + * us->dev_mutex. + */ +int usb_stor_port_reset(struct us_data *us) +{ + int result; + + /*for these devices we must use the class specific method */ + if (us->pusb_dev->quirks & USB_QUIRK_RESET) + return -EPERM; + + result = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf); + if (result < 0) + usb_stor_dbg(us, "unable to lock device for reset: %d\n", + result); + else { + /* Were we disconnected while waiting for the lock? */ + if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) { + result = -EIO; + usb_stor_dbg(us, "No reset during disconnect\n"); + } else { + result = usb_reset_device(us->pusb_dev); + usb_stor_dbg(us, "usb_reset_device returns %d\n", + result); + } + usb_unlock_device(us->pusb_dev); + } + return result; +} |