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/* Driver for USB Mass Storage compliant devices
* SCSI layer glue code
*
* 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)
*
* 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/module.h>
#include <linux/mutex.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_devinfo.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include "usb.h"
#include "scsiglue.h"
#include "debug.h"
#include "transport.h"
#include "protocol.h"
/* Vendor IDs for companies that seem to include the READ CAPACITY bug
* in all their devices
*/
#define VENDOR_ID_NOKIA 0x0421
#define VENDOR_ID_NIKON 0x04b0
#define VENDOR_ID_PENTAX 0x0a17
#define VENDOR_ID_MOTOROLA 0x22b8
/***********************************************************************
* Host functions
***********************************************************************/
static const char* host_info(struct Scsi_Host *host)
{
struct us_data *us = host_to_us(host);
return us->scsi_name;
}
static int slave_alloc (struct scsi_device *sdev)
{
struct us_data *us = host_to_us(sdev->host);
/*
* Set the INQUIRY transfer length to 36. We don't use any of
* the extra data and many devices choke if asked for more or
* less than 36 bytes.
*/
sdev->inquiry_len = 36;
/* USB has unusual DMA-alignment requirements: Although the
* starting address of each scatter-gather element doesn't matter,
* the length of each element except the last must be divisible
* by the Bulk maxpacket value. There's currently no way to
* express this by block-layer constraints, so we'll cop out
* and simply require addresses to be aligned at 512-byte
* boundaries. This is okay since most block I/O involves
* hardware sectors that are multiples of 512 bytes in length,
* and since host controllers up through USB 2.0 have maxpacket
* values no larger than 512.
*
* But it doesn't suffice for Wireless USB, where Bulk maxpacket
* values can be as large as 2048. To make that work properly
* will require changes to the block layer.
*/
blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
/* Tell the SCSI layer if we know there is more than one LUN */
if (us->protocol == USB_PR_BULK && us->max_lun > 0)
sdev->sdev_bflags |= BLIST_FORCELUN;
return 0;
}
static int slave_configure(struct scsi_device *sdev)
{
struct us_data *us = host_to_us(sdev->host);
/* Many devices have trouble transferring more than 32KB at a time,
* while others have trouble with more than 64K. At this time we
* are limiting both to 32K (64 sectores).
*/
if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
unsigned int max_sectors = 64;
if (us->fflags & US_FL_MAX_SECTORS_MIN)
max_sectors = PAGE_SIZE >> 9;
if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
blk_queue_max_hw_sectors(sdev->request_queue,
max_sectors);
} else if (sdev->type == TYPE_TAPE) {
/* Tapes need much higher max_sector limits, so just
* raise it to the maximum possible (4 GB / 512) and
* let the queue segment size sort out the real limit.
*/
blk_queue_max_hw_sectors(sdev->request_queue, 0x7FFFFF);
}
/* Some USB host controllers can't do DMA; they have to use PIO.
* They indicate this by setting their dma_mask to NULL. For
* such controllers we need to make sure the block layer sets
* up bounce buffers in addressable memory.
*/
if (!us->pusb_dev->bus->controller->dma_mask)
blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
/* We can't put these settings in slave_alloc() because that gets
* called before the device type is known. Consequently these
* settings can't be overridden via the scsi devinfo mechanism. */
if (sdev->type == TYPE_DISK) {
/* Some vendors seem to put the READ CAPACITY bug into
* all their devices -- primarily makers of cell phones
* and digital cameras. Since these devices always use
* flash media and can be expected to have an even number
* of sectors, we will always enable the CAPACITY_HEURISTICS
* flag unless told otherwise. */
switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
case VENDOR_ID_NOKIA:
case VENDOR_ID_NIKON:
case VENDOR_ID_PENTAX:
case VENDOR_ID_MOTOROLA:
if (!(us->fflags & (US_FL_FIX_CAPACITY |
US_FL_CAPACITY_OK)))
us->fflags |= US_FL_CAPACITY_HEURISTICS;
break;
}
/* Disk-type devices use MODE SENSE(6) if the protocol
* (SubClass) is Transparent SCSI, otherwise they use
* MODE SENSE(10). */
if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
sdev->use_10_for_ms = 1;
/* Many disks only accept MODE SENSE transfer lengths of
* 192 bytes (that's what Windows uses). */
sdev->use_192_bytes_for_3f = 1;
/* Some devices don't like MODE SENSE with page=0x3f,
* which is the command used for checking if a device
* is write-protected. Now that we tell the sd driver
* to do a 192-byte transfer with this command the
* majority of devices work fine, but a few still can't
* handle it. The sd driver will simply assume those
* devices are write-enabled. */
if (us->fflags & US_FL_NO_WP_DETECT)
sdev->skip_ms_page_3f = 1;
/* A number of devices have problems with MODE SENSE for
* page x08, so we will skip it. */
sdev->skip_ms_page_8 = 1;
/* Some devices don't handle VPD pages correctly */
sdev->skip_vpd_pages = 1;
/* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
sdev->no_report_opcodes = 1;
/* Do not attempt to use WRITE SAME */
sdev->no_write_same = 1;
/* Some disks return the total number of blocks in response
* to READ CAPACITY rather than the highest block number.
* If this device makes that mistake, tell the sd driver. */
if (us->fflags & US_FL_FIX_CAPACITY)
sdev->fix_capacity = 1;
/* A few disks have two indistinguishable version, one of
* which reports the correct capacity and the other does not.
* The sd driver has to guess which is the case. */
if (us->fflags & US_FL_CAPACITY_HEURISTICS)
sdev->guess_capacity = 1;
/* Some devices cannot handle READ_CAPACITY_16 */
if (us->fflags & US_FL_NO_READ_CAPACITY_16)
sdev->no_read_capacity_16 = 1;
/*
* Many devices do not respond properly to READ_CAPACITY_16.
* Tell the SCSI layer to try READ_CAPACITY_10 first.
* However some USB 3.0 drive enclosures return capacity
* modulo 2TB. Those must use READ_CAPACITY_16
*/
if (!(us->fflags & US_FL_NEEDS_CAP16))
sdev->try_rc_10_first = 1;
/* assume SPC3 or latter devices support sense size > 18 */
if (sdev->scsi_level > SCSI_SPC_2)
us->fflags |= US_FL_SANE_SENSE;
/* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
* Hardware Error) when any low-level error occurs,
* recoverable or not. Setting this flag tells the SCSI
* midlayer to retry such commands, which frequently will
* succeed and fix the error. The worst this can lead to
* is an occasional series of retries that will all fail. */
sdev->retry_hwerror = 1;
/* USB disks should allow restart. Some drives spin down
* automatically, requiring a START-STOP UNIT command. */
sdev->allow_restart = 1;
/* Some USB cardreaders have trouble reading an sdcard's last
* sector in a larger then 1 sector read, since the performance
* impact is negligible we set this flag for all USB disks */
sdev->last_sector_bug = 1;
/* Enable last-sector hacks for single-target devices using
* the Bulk-only transport, unless we already know the
* capacity will be decremented or is correct. */
if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
US_FL_SCM_MULT_TARG)) &&
us->protocol == USB_PR_BULK)
us->use_last_sector_hacks = 1;
/* Check if write cache default on flag is set or not */
if (us->fflags & US_FL_WRITE_CACHE)
sdev->wce_default_on = 1;
/* A few buggy USB-ATA bridges don't understand FUA */
if (us->fflags & US_FL_BROKEN_FUA)
sdev->broken_fua = 1;
} else {
/* Non-disk-type devices don't need to blacklist any pages
* or to force 192-byte transfer lengths for MODE SENSE.
* But they do need to use MODE SENSE(10). */
sdev->use_10_for_ms = 1;
/* Some (fake) usb cdrom devices don't like READ_DISC_INFO */
if (us->fflags & US_FL_NO_READ_DISC_INFO)
sdev->no_read_disc_info = 1;
}
/* The CB and CBI transports have no way to pass LUN values
* other than the bits in the second byte of a CDB. But those
* bits don't get set to the LUN value if the device reports
* scsi_level == 0 (UNKNOWN). Hence such devices must necessarily
* be single-LUN.
*/
if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
sdev->scsi_level == SCSI_UNKNOWN)
us->max_lun = 0;
/* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
* REMOVAL command, so suppress those commands. */
if (us->fflags & US_FL_NOT_LOCKABLE)
sdev->lockable = 0;
/* this is to satisfy the compiler, tho I don't think the
* return code is ever checked anywhere. */
return 0;
}
static int target_alloc(struct scsi_target *starget)
{
struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
/*
* Some USB drives don't support REPORT LUNS, even though they
* report a SCSI revision level above 2. Tell the SCSI layer
* not to issue that command; it will pe
|