diff options
Diffstat (limited to 'drivers/usb/storage/transport.c')
| -rw-r--r-- | drivers/usb/storage/transport.c | 165 |
1 files changed, 109 insertions, 56 deletions
diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c index 5e67f63b2e46..ffd086733421 100644 --- a/drivers/usb/storage/transport.c +++ b/drivers/usb/storage/transport.c @@ -1,4 +1,5 @@ -/* Driver for USB Mass Storage compliant devices +/* + * Driver for USB Mass Storage compliant devices * * Current development and maintenance by: * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net) @@ -109,7 +110,8 @@ * 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 +/* + * This is the completion handler which will wake us up when an URB * completes. */ static void usb_stor_blocking_completion(struct urb *urb) @@ -119,7 +121,8 @@ static void usb_stor_blocking_completion(struct urb *urb) complete(urb_done_ptr); } -/* This is the common part of the URB message submission code +/* + * 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 @@ -142,10 +145,12 @@ static int usb_stor_msg_common(struct us_data *us, int timeout) us->current_urb->context = &urb_done; us->current_urb->transfer_flags = 0; - /* we assume that if transfer_buffer isn't us->iobuf then it + /* + * 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. */ + * 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; @@ -157,8 +162,10 @@ static int usb_stor_msg_common(struct us_data *us, int timeout) return status; } - /* since the URB has been submitted successfully, it's now okay - * to cancel it */ + /* + * 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? */ @@ -220,7 +227,8 @@ int usb_stor_control_msg(struct us_data *us, unsigned int pipe, } EXPORT_SYMBOL_GPL(usb_stor_control_msg); -/* This is a version of usb_clear_halt() that allows early termination and +/* + * 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. * @@ -280,8 +288,10 @@ static int interpret_urb_result(struct us_data *us, unsigned int pipe, /* stalled */ case -EPIPE: - /* for control endpoints, (used by CB[I]) a stall indicates - * a failed command */ + /* + * 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; @@ -433,8 +443,10 @@ static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe, return USB_STOR_XFER_ERROR; } - /* since the block has been initialized successfully, it's now - * okay to cancel it */ + /* + * 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? */ @@ -515,7 +527,8 @@ EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_sg); * Transport routines ***********************************************************************/ -/* There are so many devices that report the capacity incorrectly, +/* + * There are so many devices that report the capacity incorrectly, * this routine was written to counteract some of the resulting * problems. */ @@ -533,7 +546,8 @@ static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb) [12] = 0x14 /* Record Not Found */ }; - /* If last-sector problems can't occur, whether because the + /* + * 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. @@ -559,13 +573,15 @@ static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb) if (srb->result == SAM_STAT_GOOD && scsi_get_resid(srb) == 0) { - /* The command succeeded. We know this device doesn't + /* + * 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 + /* + * 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 @@ -581,7 +597,8 @@ static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb) } done: - /* Don't reset the retry counter for TEST UNIT READY commands, + /* + * 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. */ @@ -589,7 +606,8 @@ static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb) us->last_sector_retries = 0; } -/* Invoke the transport and basic error-handling/recovery methods +/* + * 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. @@ -603,7 +621,8 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) scsi_set_resid(srb, 0); result = us->transport(srb, us); - /* if the command gets aborted by the higher layers, we need to + /* + * 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)) { @@ -628,7 +647,8 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) srb->result = SAM_STAT_GOOD; - /* Determine if we need to auto-sense + /* + * 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. @@ -728,7 +748,8 @@ Retry_Sense: goto Handle_Errors; } - /* Some devices claim to support larger sense but fail when + /* + * 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 @@ -746,7 +767,8 @@ Retry_Sense: 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 + /* + * we skip the reset if this happens to be a * multi-target device, since failure of an * auto-sense is perfectly valid */ @@ -756,7 +778,8 @@ Retry_Sense: return; } - /* If the sense data returned is larger than 18-bytes then we + /* + * 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. */ @@ -767,7 +790,8 @@ Retry_Sense: usb_stor_dbg(us, "-- SANE_SENSE support enabled\n"); us->fflags |= US_FL_SANE_SENSE; - /* Indicate to the user that we truncated their 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", @@ -795,13 +819,15 @@ Retry_Sense: SCSI_SENSE_BUFFERSIZE, 4); fm_ili = (scdd ? scdd[3] : srb->sense_buffer[2]) & 0xA0; - /* We often get empty sense data. This could indicate that + /* + * 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. + /* + * 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. */ @@ -809,7 +835,8 @@ Retry_Sense: srb->result = SAM_STAT_GOOD; srb->sense_buffer[0] = 0x0; - /* If there was a problem, report an unspecified + /* + * If there was a problem, report an unspecified * hardware error to prevent the higher layers from * entering an infinite retry loop. */ @@ -860,20 +887,26 @@ Retry_Sense: last_sector_hacks(us, srb); return; - /* Error and abort processing: try to resynchronize with the device + /* + * Error and abort processing: try to resynchronize with the device * by issuing a port reset. If that fails, try a class-specific - * device reset. */ + * device reset. + */ Handle_Errors: - /* Set the RESETTING bit, and clear the ABORTING bit so that - * the reset may proceed. */ + /* + * 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. */ + /* + * 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); @@ -891,10 +924,12 @@ Retry_Sense: /* Stop the current URB transfer */ void usb_stor_stop_transport(struct us_data *us) { - /* If the state machine is blocked waiting for an URB, + /* + * 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. */ + * 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); @@ -955,7 +990,8 @@ int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) /* STATUS STAGE */ - /* NOTE: CB does not have a status stage. Silly, I know. So + /* + * 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) @@ -967,7 +1003,8 @@ int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) if (result != USB_STOR_XFER_GOOD) return USB_STOR_TRANSPORT_ERROR; - /* UFI gives us ASC and ASCQ, like a request sense + /* + * 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 @@ -983,7 +1020,8 @@ int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) return USB_STOR_TRANSPORT_GOOD; } - /* If not UFI, we interpret the data as a result code + /* + * 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 @@ -1005,7 +1043,8 @@ int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) } return USB_STOR_TRANSPORT_ERROR; - /* the CBI spec requires that the bulk pipe must be cleared + /* + * 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: @@ -1107,9 +1146,11 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) /* DATA STAGE */ /* send/receive data payload, if there is any */ - /* Some USB-IDE converter chips need a 100us delay between the + /* + * 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. */ + * more than that, probably because of clock rate inaccuracies. + */ if (unlikely(us->fflags & US_FL_GO_SLOW)) usleep_range(125, 150); @@ -1121,7 +1162,8 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) if (result == USB_STOR_XFER_ERROR) return USB_STOR_TRANSPORT_ERROR; - /* If the device tried to send back more data than the + /* + * 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 @@ -1156,7 +1198,8 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) } } - /* See flow chart on pg 15 of the Bulk Only Transport spec for + /* + * See flow chart on pg 15 of the Bulk Only Transport spec for * an explanation of how this code works. */ @@ -1165,7 +1208,8 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) 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 + /* + * 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. */ @@ -1201,7 +1245,8 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) return USB_STOR_TRANSPORT_ERROR; } - /* Some broken devices report odd signatures, so we do not check them + /* + * 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. */ @@ -1217,11 +1262,14 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) 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 */ + /* + * 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 + /* + * Heuristically detect devices that generate bogus residues * by seeing what happens with INQUIRY and READ CAPACITY * commands. */ @@ -1259,7 +1307,8 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) return USB_STOR_TRANSPORT_FAILED; case US_BULK_STAT_PHASE: - /* phase error -- note that a transport reset will be + /* + * phase error -- note that a transport reset will be * invoked by the invoke_transport() function */ return USB_STOR_TRANSPORT_ERROR; @@ -1274,7 +1323,8 @@ EXPORT_SYMBOL_GPL(usb_stor_Bulk_transport); * Reset routines ***********************************************************************/ -/* This is the common part of the device reset code. +/* + * This is the common part of the device reset code. * * It's handy that every transport mechanism uses the control endpoint for * resets. @@ -1302,8 +1352,10 @@ static int usb_stor_reset_common(struct us_data *us, return result; } - /* Give the device some time to recover from the reset, - * but don't delay disconnect processing. */ + /* + * 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); @@ -1328,8 +1380,7 @@ static int usb_stor_reset_common(struct us_data *us, return result; } -/* This issues a CB[I] Reset to the device in question - */ +/* 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) @@ -1343,7 +1394,8 @@ int usb_stor_CB_reset(struct us_data *us) } EXPORT_SYMBOL_GPL(usb_stor_CB_reset); -/* This issues a Bulk-only Reset to the device in question, including +/* + * 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) @@ -1354,7 +1406,8 @@ int usb_stor_Bulk_reset(struct us_data *us) } EXPORT_SYMBOL_GPL(usb_stor_Bulk_reset); -/* Issue a USB port reset to the device. The caller must not hold +/* + * 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) |