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-rw-r--r--drivers/usb/storage/transport.c1450
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;
+}