USB: Add UAS driver

USB Attached SCSI is a new protocol specified jointly by the SCSI T10
committee and the USB Implementors Forum.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
[mina86@mina86.com: updated to use new USB_ prefix]
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Matthew Wilcox 2010-10-07 13:05:23 +02:00 committed by Greg Kroah-Hartman
parent ae6d22fe18
commit 115bb1ffa5
4 changed files with 773 additions and 0 deletions

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@ -5934,6 +5934,14 @@ S: Maintained
F: Documentation/usb/acm.txt
F: drivers/usb/class/cdc-acm.*
USB ATTACHED SCSI
M: Matthew Wilcox <willy@linux.intel.com>
M: Sarah Sharp <sarah.a.sharp@linux.intel.com>
L: linux-usb@vger.kernel.org
L: linux-scsi@vger.kernel.org
S: Supported
F: drivers/usb/storage/uas.c
USB BLOCK DRIVER (UB ub)
M: Pete Zaitcev <zaitcev@redhat.com>
L: linux-usb@vger.kernel.org

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@ -172,6 +172,19 @@ config USB_STORAGE_CYPRESS_ATACB
If this driver is compiled as a module, it will be named ums-cypress.
config USB_UAS
tristate "USB Attached SCSI"
depends on USB && SCSI
help
The USB Attached SCSI protocol is supported by some USB
storage devices. It permits higher performance by supporting
multiple outstanding commands.
If you don't know whether you have a UAS device, it is safe to
say 'Y' or 'M' here and the kernel will use the right driver.
If you compile this driver as a module, it will be named uas.
config USB_LIBUSUAL
bool "The shared table of common (or usual) storage devices"
depends on USB

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@ -7,6 +7,7 @@
EXTRA_CFLAGS := -Idrivers/scsi
obj-$(CONFIG_USB_UAS) += uas.o
obj-$(CONFIG_USB_STORAGE) += usb-storage.o
usb-storage-obj-$(CONFIG_USB_STORAGE_DEBUG) += debug.o

751
drivers/usb/storage/uas.c Normal file
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@ -0,0 +1,751 @@
/*
* USB Attached SCSI
* Note that this is not the same as the USB Mass Storage driver
*
* Copyright Matthew Wilcox for Intel Corp, 2010
* Copyright Sarah Sharp for Intel Corp, 2010
*
* Distributed under the terms of the GNU GPL, version two.
*/
#include <linux/blkdev.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/usb.h>
#include <linux/usb/storage.h>
#include <scsi/scsi.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tcq.h>
/* Common header for all IUs */
struct iu {
__u8 iu_id;
__u8 rsvd1;
__be16 tag;
};
enum {
IU_ID_COMMAND = 0x01,
IU_ID_STATUS = 0x03,
IU_ID_RESPONSE = 0x04,
IU_ID_TASK_MGMT = 0x05,
IU_ID_READ_READY = 0x06,
IU_ID_WRITE_READY = 0x07,
};
struct command_iu {
__u8 iu_id;
__u8 rsvd1;
__be16 tag;
__u8 prio_attr;
__u8 rsvd5;
__u8 len;
__u8 rsvd7;
struct scsi_lun lun;
__u8 cdb[16]; /* XXX: Overflow-checking tools may misunderstand */
};
struct sense_iu {
__u8 iu_id;
__u8 rsvd1;
__be16 tag;
__be16 status_qual;
__u8 status;
__u8 service_response;
__u8 rsvd8[6];
__be16 len;
__u8 sense[SCSI_SENSE_BUFFERSIZE];
};
/*
* The r00-r01c specs define this version of the SENSE IU data structure.
* It's still in use by several different firmware releases.
*/
struct sense_iu_old {
__u8 iu_id;
__u8 rsvd1;
__be16 tag;
__be16 len;
__u8 status;
__u8 service_response;
__u8 sense[SCSI_SENSE_BUFFERSIZE];
};
enum {
CMD_PIPE_ID = 1,
STATUS_PIPE_ID = 2,
DATA_IN_PIPE_ID = 3,
DATA_OUT_PIPE_ID = 4,
UAS_SIMPLE_TAG = 0,
UAS_HEAD_TAG = 1,
UAS_ORDERED_TAG = 2,
UAS_ACA = 4,
};
struct uas_dev_info {
struct usb_interface *intf;
struct usb_device *udev;
int qdepth;
unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
unsigned use_streams:1;
unsigned uas_sense_old:1;
};
enum {
ALLOC_SENSE_URB = (1 << 0),
SUBMIT_SENSE_URB = (1 << 1),
ALLOC_DATA_IN_URB = (1 << 2),
SUBMIT_DATA_IN_URB = (1 << 3),
ALLOC_DATA_OUT_URB = (1 << 4),
SUBMIT_DATA_OUT_URB = (1 << 5),
ALLOC_CMD_URB = (1 << 6),
SUBMIT_CMD_URB = (1 << 7),
};
/* Overrides scsi_pointer */
struct uas_cmd_info {
unsigned int state;
unsigned int stream;
struct urb *cmd_urb;
struct urb *sense_urb;
struct urb *data_in_urb;
struct urb *data_out_urb;
struct list_head list;
};
/* I hate forward declarations, but I actually have a loop */
static int uas_submit_urbs(struct scsi_cmnd *cmnd,
struct uas_dev_info *devinfo, gfp_t gfp);
static DEFINE_SPINLOCK(uas_work_lock);
static LIST_HEAD(uas_work_list);
static void uas_do_work(struct work_struct *work)
{
struct uas_cmd_info *cmdinfo;
struct list_head list;
spin_lock_irq(&uas_work_lock);
list_replace_init(&uas_work_list, &list);
spin_unlock_irq(&uas_work_lock);
list_for_each_entry(cmdinfo, &list, list) {
struct scsi_pointer *scp = (void *)cmdinfo;
struct scsi_cmnd *cmnd = container_of(scp,
struct scsi_cmnd, SCp);
uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_KERNEL);
}
}
static DECLARE_WORK(uas_work, uas_do_work);
static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
{
struct sense_iu *sense_iu = urb->transfer_buffer;
struct scsi_device *sdev = cmnd->device;
if (urb->actual_length > 16) {
unsigned len = be16_to_cpup(&sense_iu->len);
if (len + 16 != urb->actual_length) {
int newlen = min(len + 16, urb->actual_length) - 16;
if (newlen < 0)
newlen = 0;
sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
"disagrees with IU sense data length %d, "
"using %d bytes of sense data\n", __func__,
urb->actual_length, len, newlen);
len = newlen;
}
memcpy(cmnd->sense_buffer, sense_iu->sense, len);
}
cmnd->result = sense_iu->status;
if (sdev->current_cmnd)
sdev->current_cmnd = NULL;
cmnd->scsi_done(cmnd);
usb_free_urb(urb);
}
static void uas_sense_old(struct urb *urb, struct scsi_cmnd *cmnd)
{
struct sense_iu_old *sense_iu = urb->transfer_buffer;
struct scsi_device *sdev = cmnd->device;
if (urb->actual_length > 8) {
unsigned len = be16_to_cpup(&sense_iu->len) - 2;
if (len + 8 != urb->actual_length) {
int newlen = min(len + 8, urb->actual_length) - 8;
if (newlen < 0)
newlen = 0;
sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
"disagrees with IU sense data length %d, "
"using %d bytes of sense data\n", __func__,
urb->actual_length, len, newlen);
len = newlen;
}
memcpy(cmnd->sense_buffer, sense_iu->sense, len);
}
cmnd->result = sense_iu->status;
if (sdev->current_cmnd)
sdev->current_cmnd = NULL;
cmnd->scsi_done(cmnd);
usb_free_urb(urb);
}
static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
unsigned direction)
{
struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
int err;
cmdinfo->state = direction | SUBMIT_SENSE_URB;
err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
if (err) {
spin_lock(&uas_work_lock);
list_add_tail(&cmdinfo->list, &uas_work_list);
spin_unlock(&uas_work_lock);
schedule_work(&uas_work);
}
}
static void uas_stat_cmplt(struct urb *urb)
{
struct iu *iu = urb->transfer_buffer;
struct scsi_device *sdev = urb->context;
struct uas_dev_info *devinfo = sdev->hostdata;
struct scsi_cmnd *cmnd;
u16 tag;
if (urb->status) {
dev_err(&urb->dev->dev, "URB BAD STATUS %d\n", urb->status);
usb_free_urb(urb);
return;
}
tag = be16_to_cpup(&iu->tag) - 1;
if (sdev->current_cmnd)
cmnd = sdev->current_cmnd;
else
cmnd = scsi_find_tag(sdev, tag);
if (!cmnd)
return;
switch (iu->iu_id) {
case IU_ID_STATUS:
if (urb->actual_length < 16)
devinfo->uas_sense_old = 1;
if (devinfo->uas_sense_old)
uas_sense_old(urb, cmnd);
else
uas_sense(urb, cmnd);
break;
case IU_ID_READ_READY:
uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
break;
case IU_ID_WRITE_READY:
uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
break;
default:
scmd_printk(KERN_ERR, cmnd,
"Bogus IU (%d) received on status pipe\n", iu->iu_id);
}
}
static void uas_data_cmplt(struct urb *urb)
{
struct scsi_data_buffer *sdb = urb->context;
sdb->resid = sdb->length - urb->actual_length;
usb_free_urb(urb);
}
static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
unsigned int pipe, u16 stream_id,
struct scsi_data_buffer *sdb,
enum dma_data_direction dir)
{
struct usb_device *udev = devinfo->udev;
struct urb *urb = usb_alloc_urb(0, gfp);
if (!urb)
goto out;
usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length, uas_data_cmplt,
sdb);
if (devinfo->use_streams)
urb->stream_id = stream_id;
urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
urb->sg = sdb->table.sgl;
out:
return urb;
}
static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
struct scsi_cmnd *cmnd, u16 stream_id)
{
struct usb_device *udev = devinfo->udev;
struct urb *urb = usb_alloc_urb(0, gfp);
struct sense_iu *iu;
if (!urb)
goto out;
iu = kmalloc(sizeof(*iu), gfp);
if (!iu)
goto free;
usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
uas_stat_cmplt, cmnd->device);
urb->stream_id = stream_id;
urb->transfer_flags |= URB_FREE_BUFFER;
out:
return urb;
free:
usb_free_urb(urb);
return NULL;
}
static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
struct scsi_cmnd *cmnd, u16 stream_id)
{
struct usb_device *udev = devinfo->udev;
struct scsi_device *sdev = cmnd->device;
struct urb *urb = usb_alloc_urb(0, gfp);
struct command_iu *iu;
int len;
if (!urb)
goto out;
len = cmnd->cmd_len - 16;
if (len < 0)
len = 0;
len = ALIGN(len, 4);
iu = kmalloc(sizeof(*iu) + len, gfp);
if (!iu)
goto free;
iu->iu_id = IU_ID_COMMAND;
iu->tag = cpu_to_be16(stream_id);
if (sdev->ordered_tags && (cmnd->request->cmd_flags & REQ_HARDBARRIER))
iu->prio_attr = UAS_ORDERED_TAG;
else
iu->prio_attr = UAS_SIMPLE_TAG;
iu->len = len;
int_to_scsilun(sdev->lun, &iu->lun);
memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
usb_free_urb, NULL);
urb->transfer_flags |= URB_FREE_BUFFER;
out:
return urb;
free:
usb_free_urb(urb);
return NULL;
}
/*
* Why should I request the Status IU before sending the Command IU? Spec
* says to, but also says the device may receive them in any order. Seems
* daft to me.
*/
static int uas_submit_urbs(struct scsi_cmnd *cmnd,
struct uas_dev_info *devinfo, gfp_t gfp)
{
struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
if (cmdinfo->state & ALLOC_SENSE_URB) {
cmdinfo->sense_urb = uas_alloc_sense_urb(devinfo, gfp, cmnd,
cmdinfo->stream);
if (!cmdinfo->sense_urb)
return SCSI_MLQUEUE_DEVICE_BUSY;
cmdinfo->state &= ~ALLOC_SENSE_URB;
}
if (cmdinfo->state & SUBMIT_SENSE_URB) {
if (usb_submit_urb(cmdinfo->sense_urb, gfp)) {
scmd_printk(KERN_INFO, cmnd,
"sense urb submission failure\n");
return SCSI_MLQUEUE_DEVICE_BUSY;
}
cmdinfo->state &= ~SUBMIT_SENSE_URB;
}
if (cmdinfo->state & ALLOC_DATA_IN_URB) {
cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, gfp,
devinfo->data_in_pipe, cmdinfo->stream,
scsi_in(cmnd), DMA_FROM_DEVICE);
if (!cmdinfo->data_in_urb)
return SCSI_MLQUEUE_DEVICE_BUSY;
cmdinfo->state &= ~ALLOC_DATA_IN_URB;
}
if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
if (usb_submit_urb(cmdinfo->data_in_urb, gfp)) {
scmd_printk(KERN_INFO, cmnd,
"data in urb submission failure\n");
return SCSI_MLQUEUE_DEVICE_BUSY;
}
cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
}
if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, gfp,
devinfo->data_out_pipe, cmdinfo->stream,
scsi_out(cmnd), DMA_TO_DEVICE);
if (!cmdinfo->data_out_urb)
return SCSI_MLQUEUE_DEVICE_BUSY;
cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
}
if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
if (usb_submit_urb(cmdinfo->data_out_urb, gfp)) {
scmd_printk(KERN_INFO, cmnd,
"data out urb submission failure\n");
return SCSI_MLQUEUE_DEVICE_BUSY;
}
cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
}
if (cmdinfo->state & ALLOC_CMD_URB) {
cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, gfp, cmnd,
cmdinfo->stream);
if (!cmdinfo->cmd_urb)
return SCSI_MLQUEUE_DEVICE_BUSY;
cmdinfo->state &= ~ALLOC_CMD_URB;
}
if (cmdinfo->state & SUBMIT_CMD_URB) {
if (usb_submit_urb(cmdinfo->cmd_urb, gfp)) {
scmd_printk(KERN_INFO, cmnd,
"cmd urb submission failure\n");
return SCSI_MLQUEUE_DEVICE_BUSY;
}
cmdinfo->state &= ~SUBMIT_CMD_URB;
}
return 0;
}
static int uas_queuecommand(struct scsi_cmnd *cmnd,
void (*done)(struct scsi_cmnd *))
{
struct scsi_device *sdev = cmnd->device;
struct uas_dev_info *devinfo = sdev->hostdata;
struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
int err;
BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
if (!cmdinfo->sense_urb && sdev->current_cmnd)
return SCSI_MLQUEUE_DEVICE_BUSY;
if (blk_rq_tagged(cmnd->request)) {
cmdinfo->stream = cmnd->request->tag + 1;
} else {
sdev->current_cmnd = cmnd;
cmdinfo->stream = 1;
}
cmnd->scsi_done = done;
cmdinfo->state = ALLOC_SENSE_URB | SUBMIT_SENSE_URB |
ALLOC_CMD_URB | SUBMIT_CMD_URB;
switch (cmnd->sc_data_direction) {
case DMA_FROM_DEVICE:
cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
break;
case DMA_BIDIRECTIONAL:
cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
case DMA_TO_DEVICE:
cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
case DMA_NONE:
break;
}
if (!devinfo->use_streams) {
cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
cmdinfo->stream = 0;
}
err = uas_submit_urbs(cmnd, devinfo, GFP_ATOMIC);
if (err) {
/* If we did nothing, give up now */
if (cmdinfo->state & SUBMIT_SENSE_URB) {
usb_free_urb(cmdinfo->sense_urb);
return SCSI_MLQUEUE_DEVICE_BUSY;
}
spin_lock(&uas_work_lock);
list_add_tail(&cmdinfo->list, &uas_work_list);
spin_unlock(&uas_work_lock);
schedule_work(&uas_work);
}
return 0;
}
static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
{
struct scsi_device *sdev = cmnd->device;
sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
cmnd->request->tag);
/* XXX: Send ABORT TASK Task Management command */
return FAILED;
}
static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
{
struct scsi_device *sdev = cmnd->device;
sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
cmnd->request->tag);
/* XXX: Send LOGICAL UNIT RESET Task Management command */
return FAILED;
}
static int uas_eh_target_reset_handler(struct scsi_cmnd *cmnd)
{
struct scsi_device *sdev = cmnd->device;
sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
cmnd->request->tag);
/* XXX: Can we reset just the one USB interface?
* Would calling usb_set_interface() have the right effect?
*/
return FAILED;
}
static int uas_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
{
struct scsi_device *sdev = cmnd->device;
struct uas_dev_info *devinfo = sdev->hostdata;
struct usb_device *udev = devinfo->udev;
sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
cmnd->request->tag);
if (usb_reset_device(udev))
return SUCCESS;
return FAILED;
}
static int uas_slave_alloc(struct scsi_device *sdev)
{
sdev->hostdata = (void *)sdev->host->hostdata[0];
return 0;
}
static int uas_slave_configure(struct scsi_device *sdev)
{
struct uas_dev_info *devinfo = sdev->hostdata;
scsi_set_tag_type(sdev, MSG_ORDERED_TAG);
scsi_activate_tcq(sdev, devinfo->qdepth - 1);
return 0;
}
static struct scsi_host_template uas_host_template = {
.module = THIS_MODULE,
.name = "uas",
.queuecommand = uas_queuecommand,
.slave_alloc = uas_slave_alloc,
.slave_configure = uas_slave_configure,
.eh_abort_handler = uas_eh_abort_handler,
.eh_device_reset_handler = uas_eh_device_reset_handler,
.eh_target_reset_handler = uas_eh_target_reset_handler,
.eh_bus_reset_handler = uas_eh_bus_reset_handler,
.can_queue = 65536, /* Is there a limit on the _host_ ? */
.this_id = -1,
.sg_tablesize = SG_NONE,
.cmd_per_lun = 1, /* until we override it */
.skip_settle_delay = 1,
.ordered_tag = 1,
};
static struct usb_device_id uas_usb_ids[] = {
{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
/* 0xaa is a prototype device I happen to have access to */
{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, 0xaa) },
{ }
};
MODULE_DEVICE_TABLE(usb, uas_usb_ids);
static void uas_configure_endpoints(struct uas_dev_info *devinfo)
{
struct usb_host_endpoint *eps[4] = { };
struct usb_interface *intf = devinfo->intf;
struct usb_device *udev = devinfo->udev;
struct usb_host_endpoint *endpoint = intf->cur_altsetting->endpoint;
unsigned i, n_endpoints = intf->cur_altsetting->desc.bNumEndpoints;
devinfo->uas_sense_old = 0;
for (i = 0; i < n_endpoints; i++) {
unsigned char *extra = endpoint[i].extra;
int len = endpoint[i].extralen;
while (len > 1) {
if (extra[1] == USB_DT_PIPE_USAGE) {
unsigned pipe_id = extra[2];
if (pipe_id > 0 && pipe_id < 5)
eps[pipe_id - 1] = &endpoint[i];
break;
}
len -= extra[0];
extra += extra[0];
}
}
/*
* Assume that if we didn't find a control pipe descriptor, we're
* using a device with old firmware that happens to be set up like
* this.
*/
if (!eps[0]) {
devinfo->cmd_pipe = usb_sndbulkpipe(udev, 1);
devinfo->status_pipe = usb_rcvbulkpipe(udev, 1);
devinfo->data_in_pipe = usb_rcvbulkpipe(udev, 2);
devinfo->data_out_pipe = usb_sndbulkpipe(udev, 2);
eps[1] = usb_pipe_endpoint(udev, devinfo->status_pipe);
eps[2] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
eps[3] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
} else {
devinfo->cmd_pipe = usb_sndbulkpipe(udev,
eps[0]->desc.bEndpointAddress);
devinfo->status_pipe = usb_rcvbulkpipe(udev,
eps[1]->desc.bEndpointAddress);
devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
eps[2]->desc.bEndpointAddress);
devinfo->data_out_pipe = usb_sndbulkpipe(udev,
eps[3]->desc.bEndpointAddress);
}
devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1, 3, 256,
GFP_KERNEL);
if (devinfo->qdepth < 0) {
devinfo->qdepth = 256;
devinfo->use_streams = 0;
} else {
devinfo->use_streams = 1;
}
}
/*
* XXX: What I'd like to do here is register a SCSI host for each USB host in
* the system. Follow usb-storage's design of registering a SCSI host for
* each USB device for the moment. Can implement this by walking up the
* USB hierarchy until we find a USB host.
*/
static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
int result;
struct Scsi_Host *shost;
struct uas_dev_info *devinfo;
struct usb_device *udev = interface_to_usbdev(intf);
if (id->bInterfaceProtocol == 0x50) {
int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
/* XXX: Shouldn't assume that 1 is the alternative we want */
int ret = usb_set_interface(udev, ifnum, 1);
if (ret)
return -ENODEV;
}
devinfo = kmalloc(sizeof(struct uas_dev_info), GFP_KERNEL);
if (!devinfo)
return -ENOMEM;
result = -ENOMEM;
shost = scsi_host_alloc(&uas_host_template, sizeof(void *));
if (!shost)
goto free;
shost->max_cmd_len = 16 + 252;
shost->max_id = 1;
shost->sg_tablesize = udev->bus->sg_tablesize;
result = scsi_add_host(shost, &intf->dev);
if (result)
goto free;
shost->hostdata[0] = (unsigned long)devinfo;
devinfo->intf = intf;
devinfo->udev = udev;
uas_configure_endpoints(devinfo);
scsi_scan_host(shost);
usb_set_intfdata(intf, shost);
return result;
free:
kfree(devinfo);
if (shost)
scsi_host_put(shost);
return result;
}
static int uas_pre_reset(struct usb_interface *intf)
{
/* XXX: Need to return 1 if it's not our device in error handling */
return 0;
}
static int uas_post_reset(struct usb_interface *intf)
{
/* XXX: Need to return 1 if it's not our device in error handling */
return 0;
}
static void uas_disconnect(struct usb_interface *intf)
{
struct usb_device *udev = interface_to_usbdev(intf);
struct usb_host_endpoint *eps[3];
struct Scsi_Host *shost = usb_get_intfdata(intf);
struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
scsi_remove_host(shost);
eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
usb_free_streams(intf, eps, 3, GFP_KERNEL);
kfree(devinfo);
}
/*
* XXX: Should this plug into libusual so we can auto-upgrade devices from
* Bulk-Only to UAS?
*/
static struct usb_driver uas_driver = {
.name = "uas",
.probe = uas_probe,
.disconnect = uas_disconnect,
.pre_reset = uas_pre_reset,
.post_reset = uas_post_reset,
.id_table = uas_usb_ids,
};
static int uas_init(void)
{
return usb_register(&uas_driver);
}
static void uas_exit(void)
{
usb_deregister(&uas_driver);
}
module_init(uas_init);
module_exit(uas_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Matthew Wilcox and Sarah Sharp");