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authorMatthew Wilcox <matthew.r.wilcox@intel.com>2010-10-07 13:05:23 +0200
committerGreg Kroah-Hartman <gregkh@suse.de>2010-10-22 10:21:50 -0700
commit115bb1ffa54c3934f3617bdd4e4dfc68b11e1e69 (patch)
tree873eac5e1a90e0374d2d1008f15492efc772f0cc
parentae6d22fe1812ce8d40add3eb74ede9cfd2eae44f (diff)
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>
-rw-r--r--MAINTAINERS8
-rw-r--r--drivers/usb/storage/Kconfig13
-rw-r--r--drivers/usb/storage/Makefile1
-rw-r--r--drivers/usb/storage/uas.c751
4 files changed, 773 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index f2a2b8e647c5..8dac57f53d87 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -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
diff --git a/drivers/usb/storage/Kconfig b/drivers/usb/storage/Kconfig
index 8a372bac0e43..f2767cf2e229 100644
--- a/drivers/usb/storage/Kconfig
+++ b/drivers/usb/storage/Kconfig
@@ -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
diff --git a/drivers/usb/storage/Makefile b/drivers/usb/storage/Makefile
index ef7e5a8ceab5..0332aa5df24f 100644
--- a/drivers/usb/storage/Makefile
+++ b/drivers/usb/storage/Makefile
@@ -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
diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
new file mode 100644
index 000000000000..2054b1e25a65
--- /dev/null
+++ b/drivers/usb/storage/uas.c
@@ -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");