diff --git a/MAINTAINERS b/MAINTAINERS index f2a2b8e647c56ce87a6bf527a99296e67125fb56..8dac57f53d870f32db9a1ac43c7c4965a7d3dccf 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 +M: Sarah Sharp +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 L: linux-usb@vger.kernel.org diff --git a/drivers/usb/storage/Kconfig b/drivers/usb/storage/Kconfig index 8a372bac0e435cf4d57e0a588904bb5d918347f5..f2767cf2e229d4bc0868c3c0695982448a77407f 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 ef7e5a8ceab56616af1b86535144b65b5584d66b..0332aa5df24fc3357a105941e5941451e51711b9 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 0000000000000000000000000000000000000000..2054b1e25a6554e3e62e8c96c9ccb8b4dc7fa893 --- /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 +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +/* 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");