/* Driver for USB Mass Storage compliant devices * * $Id: transport.c,v 1.47 2002/04/22 03:39:43 mdharm Exp $ * * 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. * * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more * information about this driver. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2, or (at your option) any * later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/sched.h> #include <linux/errno.h> #include <linux/slab.h> #include <scsi/scsi.h> #include <scsi/scsi_cmnd.h> #include <scsi/scsi_device.h> #include "usb.h" #include "transport.h" #include "protocol.h" #include "scsiglue.h" #include "debug.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->flags 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->flags * 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->flags 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 = (struct completion *)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/disconnect processing */ if (us->flags & ABORTING_OR_DISCONNECTING) 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->actual_length = 0; us->current_urb->error_count = 0; us->current_urb->status = 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. */ us->current_urb->transfer_flags = URB_NO_SETUP_DMA_MAP; 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; us->current_urb->setup_dma = us->cr_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->flags); /* did an abort/disconnect occur during the submission? */ if (us->flags & ABORTING_OR_DISCONNECTING) { /* cancel the URB, if it hasn't been cancelled already */ if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) { US_DEBUGP("-- 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->flags); if (timeleft <= 0) { US_DEBUGP("%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; US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n", __FUNCTION__, 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; } /* 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); /* reset the endpoint toggle */ if (result >= 0) usb_settoggle(us->pusb_dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0); US_DEBUGP("%s: result = %d\n", __FUNCTION__, result); return result; } /* * 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) { US_DEBUGP("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) { US_DEBUGP("-- short transfer\n"); return USB_STOR_XFER_SHORT; } US_DEBUGP("-- 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)) { US_DEBUGP("-- stall on control pipe\n"); return USB_STOR_XFER_STALLED; } /* for other sorts of endpoint, clear the stall */ US_DEBUGP("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: US_DEBUGP("-- babble\n"); return USB_STOR_XFER_LONG; /* the transfer was cancelled by abort, disconnect, or timeout */ case -ECONNRESET: US_DEBUGP("-- transfer cancelled\n"); return USB_STOR_XFER_ERROR; /* short scatter-gather read transfer */ case -EREMOTEIO: US_DEBUGP("-- short read transfer\n"); return USB_STOR_XFER_SHORT; /* abort or disconnect in progress */ case -EIO: US_DEBUGP("-- abort or disconnect in progress\n"); return USB_STOR_XFER_ERROR; /* the catch-all error case */ default: US_DEBUGP("-- 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; US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n", __FUNCTION__, 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); } /* * 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; US_DEBUGP("%s: xfer %u bytes\n", __FUNCTION__, length); /* calculate the max packet size */ maxp = usb_maxpacket(us->pusb_dev, pipe, usb_pipeout(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; US_DEBUGP("%s: xfer %u bytes\n", __FUNCTION__, 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); } /* * 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/disconnect processing */ if (us->flags & ABORTING_OR_DISCONNECTING) return USB_STOR_XFER_ERROR; /* initialize the scatter-gather request block */ US_DEBUGP("%s: xfer %u bytes, %d entries\n", __FUNCTION__, length, num_sg); result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0, sg, num_sg, length, GFP_NOIO); if (result) { US_DEBUGP("usb_sg_init returned %d\n", result); return 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->flags); /* did an abort/disconnect occur during the submission? */ if (us->flags & ABORTING_OR_DISCONNECTING) { /* cancel the request, if it hasn't been cancelled already */ if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) { US_DEBUGP("-- 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->flags); 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); } /* * 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; } /*********************************************************************** * Transport routines ***********************************************************************/ /* 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 */ srb->resid = 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->flags)) { US_DEBUGP("-- 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) { US_DEBUGP("-- 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; 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 == US_PR_CB || us->protocol == US_PR_DPCM_USB) && srb->sc_data_direction != DMA_FROM_DEVICE) { US_DEBUGP("-- CB transport device requiring auto-sense\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) { US_DEBUGP("-- transport indicates command failure\n"); need_auto_sense = 1; } /* * 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 ((srb->resid > 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))) { US_DEBUGP("-- unexpectedly short transfer\n"); } /* Now, if we need to do the auto-sense, let's do it */ if (need_auto_sense) { int temp_result; void* old_request_buffer; unsigned short old_sg; unsigned old_request_bufflen; unsigned char old_sc_data_direction; unsigned char old_cmd_len; unsigned char old_cmnd[MAX_COMMAND_SIZE]; int old_resid; US_DEBUGP("Issuing auto-REQUEST_SENSE\n"); /* save the old command */ memcpy(old_cmnd, srb->cmnd, MAX_COMMAND_SIZE); old_cmd_len = srb->cmd_len; /* set the command and the LUN */ memset(srb->cmnd, 0, MAX_COMMAND_SIZE); srb->cmnd[0] = REQUEST_SENSE; srb->cmnd[1] = old_cmnd[1] & 0xE0; srb->cmnd[4] = 18; /* FIXME: we must do the protocol translation here */ if (us->subclass == US_SC_RBC || us->subclass == US_SC_SCSI) srb->cmd_len = 6; else srb->cmd_len = 12; /* set the transfer direction */ old_sc_data_direction = srb->sc_data_direction; srb->sc_data_direction = DMA_FROM_DEVICE; /* use the new buffer we have */ old_request_buffer = srb->request_buffer; srb->request_buffer = us->sensebuf; /* set the buffer length for transfer */ old_request_bufflen = srb->request_bufflen; srb->request_bufflen = US_SENSE_SIZE; /* set up for no scatter-gather use */ old_sg = srb->use_sg; srb->use_sg = 0; /* issue the auto-sense command */ old_resid = srb->resid; srb->resid = 0; temp_result = us->transport(us->srb, us); /* let's clean up right away */ memcpy(srb->sense_buffer, us->sensebuf, US_SENSE_SIZE); srb->resid = old_resid; srb->request_buffer = old_request_buffer; srb->request_bufflen = old_request_bufflen; srb->use_sg = old_sg; srb->sc_data_direction = old_sc_data_direction; srb->cmd_len = old_cmd_len; memcpy(srb->cmnd, old_cmnd, MAX_COMMAND_SIZE); if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) { US_DEBUGP("-- auto-sense aborted\n"); srb->result = DID_ABORT << 16; goto Handle_Errors; } if (temp_result != USB_STOR_TRANSPORT_GOOD) { US_DEBUGP("-- 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->flags & US_FL_SCM_MULT_TARG)) goto Handle_Errors; return; } US_DEBUGP("-- Result from auto-sense is %d\n", temp_result); US_DEBUGP("-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n", srb->sense_buffer[0], srb->sense_buffer[2] & 0xf, srb->sense_buffer[12], srb->sense_buffer[13]); #ifdef CONFIG_USB_STORAGE_DEBUG usb_stor_show_sense( srb->sense_buffer[2] & 0xf, srb->sense_buffer[12], srb->sense_buffer[13]); #endif /* set the result so the higher layers expect this data */ srb->result = SAM_STAT_CHECK_CONDITION; /* 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 && /* Filemark 0, ignore EOM, ILI 0, no sense */ (srb->sense_buffer[2] & 0xaf) == 0 && /* No ASC or ASCQ */ srb->sense_buffer[12] == 0 && srb->sense_buffer[13] == 0) { srb->result = SAM_STAT_GOOD; srb->sense_buffer[0] = 0x0; } } /* Did we transfer less than the minimum amount required? */ if (srb->result == SAM_STAT_GOOD && srb->request_bufflen - srb->resid < srb->underflow) srb->result = (DID_ERROR << 16) | (SUGGEST_RETRY << 24); 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->flags); clear_bit(US_FLIDX_ABORTING, &us->flags); 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->flags); } /* Stop the current URB transfer */ void usb_stor_stop_transport(struct us_data *us) { US_DEBUGP("%s called\n", __FUNCTION__); /* 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->flags)) { US_DEBUGP("-- 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->flags)) { US_DEBUGP("-- cancelling sg request\n"); usb_sg_cancel(&us->current_sg); } } /* * Control/Bulk/Interrupt transport */ int usb_stor_CBI_transport(struct scsi_cmnd *srb, struct us_data *us) { unsigned int transfer_length = srb->request_bufflen; unsigned int pipe = 0; int result; /* COMMAND STAGE */ /* let's send the command via the control pipe */ result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe, US_CBI_ADSC, USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, us->ifnum, srb->cmnd, srb->cmd_len); /* check the return code for the command */ US_DEBUGP("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_transfer_sg(us, pipe, srb->request_buffer, transfer_length, srb->use_sg, &srb->resid); US_DEBUGP("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 */ result = usb_stor_intr_transfer(us, us->iobuf, 2); US_DEBUGP("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 == US_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]) { US_DEBUGP("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; } /* * Control/Bulk transport */ int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) { unsigned int transfer_length = srb->request_bufflen; int result; /* COMMAND STAGE */ /* let's send the command via the control pipe */ result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe, US_CBI_ADSC, USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, us->ifnum, srb->cmnd, srb->cmd_len); /* check the return code for the command */ US_DEBUGP("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) { unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? us->recv_bulk_pipe : us->send_bulk_pipe; result = usb_stor_bulk_transfer_sg(us, pipe, srb->request_buffer, transfer_length, srb->use_sg, &srb->resid); US_DEBUGP("CB 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. */ return USB_STOR_TRANSPORT_GOOD; } /* * 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, HZ); US_DEBUGP("GetMaxLUN command result is %d, data is %d\n", result, us->iobuf[0]); /* if we have a successful request, return the result */ if (result > 0) return us->iobuf[0]; /* * Some devices (i.e. Iomega Zip100) need this -- apparently * the bulk pipes get STALLed when the GetMaxLUN request is * processed. This is, in theory, harmless to all other devices * (regardless of if they stall or not). */ if (result == -EPIPE) { usb_stor_clear_halt(us, us->recv_bulk_pipe); usb_stor_clear_halt(us, us->send_bulk_pipe); } /* * 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 = srb->request_bufflen; 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->flags & 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 ? 1 << 7 : 0; bcb->Tag = ++us->tag; bcb->Lun = srb->device->lun; if (us->flags & 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 */ US_DEBUGP("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); US_DEBUGP("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->flags & US_FL_GO_SLOW)) udelay(125); 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_transfer_sg(us, pipe, srb->request_buffer, transfer_length, srb->use_sg, &srb->resid); US_DEBUGP("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 * the command, we'll return fake sense data indicating * Illegal Request, Invalid Field in CDB. */ if (result == USB_STOR_XFER_LONG) fake_sense = 1; } /* 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 */ US_DEBUGP("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) { US_DEBUGP("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 */ US_DEBUGP("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 */ US_DEBUGP("Bulk status result = %d\n", result); if (result != USB_STOR_XFER_GOOD) return USB_STOR_TRANSPORT_ERROR; /* check bulk status */ residue = le32_to_cpu(bcs->Residue); US_DEBUGP("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 || bcs->Status > US_BULK_STAT_PHASE) { US_DEBUGP("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)) US_DEBUGP("Learnt BCS signature 0x%08X\n", le32_to_cpu(us->bcs_signature)); } else if (bcs->Signature != us->bcs_signature) { US_DEBUGP("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) { if (!(us->flags & US_FL_IGNORE_RESIDUE)) { residue = min(residue, transfer_length); srb->resid = max(srb->resid, (int) 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; } /*********************************************************************** * 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->flags)) { US_DEBUGP("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) { US_DEBUGP("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->flags), HZ*6); if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) { US_DEBUGP("Reset interrupted by disconnect\n"); return -EIO; } US_DEBUGP("Soft reset: clearing bulk-in endpoint halt\n"); result = usb_stor_clear_halt(us, us->recv_bulk_pipe); US_DEBUGP("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) US_DEBUGP("Soft reset failed\n"); else US_DEBUGP("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) { US_DEBUGP("%s called\n", __FUNCTION__); 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); } /* 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) { US_DEBUGP("%s called\n", __FUNCTION__); return usb_stor_reset_common(us, US_BULK_RESET_REQUEST, USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, us->ifnum, NULL, 0); } /* 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, rc_lock; result = rc_lock = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf); if (result < 0) US_DEBUGP("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->flags)) { result = -EIO; US_DEBUGP("No reset during disconnect\n"); } else { result = usb_reset_composite_device( us->pusb_dev, us->pusb_intf); US_DEBUGP("usb_reset_composite_device returns %d\n", result); } if (rc_lock) usb_unlock_device(us->pusb_dev); } return result; }