Merge branch 'for-next'
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / usb / storage / uas.c
blob23f0dd9c36d4df92fe08b88dd679f65194dbf135
1 /*
2 * USB Attached SCSI
3 * Note that this is not the same as the USB Mass Storage driver
5 * Copyright Matthew Wilcox for Intel Corp, 2010
6 * Copyright Sarah Sharp for Intel Corp, 2010
8 * Distributed under the terms of the GNU GPL, version two.
9 */
11 #include <linux/blkdev.h>
12 #include <linux/slab.h>
13 #include <linux/types.h>
14 #include <linux/usb.h>
15 #include <linux/usb/storage.h>
17 #include <scsi/scsi.h>
18 #include <scsi/scsi_dbg.h>
19 #include <scsi/scsi_cmnd.h>
20 #include <scsi/scsi_device.h>
21 #include <scsi/scsi_host.h>
22 #include <scsi/scsi_tcq.h>
24 /* Common header for all IUs */
25 struct iu {
26 __u8 iu_id;
27 __u8 rsvd1;
28 __be16 tag;
31 enum {
32 IU_ID_COMMAND = 0x01,
33 IU_ID_STATUS = 0x03,
34 IU_ID_RESPONSE = 0x04,
35 IU_ID_TASK_MGMT = 0x05,
36 IU_ID_READ_READY = 0x06,
37 IU_ID_WRITE_READY = 0x07,
40 struct command_iu {
41 __u8 iu_id;
42 __u8 rsvd1;
43 __be16 tag;
44 __u8 prio_attr;
45 __u8 rsvd5;
46 __u8 len;
47 __u8 rsvd7;
48 struct scsi_lun lun;
49 __u8 cdb[16]; /* XXX: Overflow-checking tools may misunderstand */
53 * Also used for the Read Ready and Write Ready IUs since they have the
54 * same first four bytes
56 struct sense_iu {
57 __u8 iu_id;
58 __u8 rsvd1;
59 __be16 tag;
60 __be16 status_qual;
61 __u8 status;
62 __u8 rsvd7[7];
63 __be16 len;
64 __u8 sense[SCSI_SENSE_BUFFERSIZE];
68 * The r00-r01c specs define this version of the SENSE IU data structure.
69 * It's still in use by several different firmware releases.
71 struct sense_iu_old {
72 __u8 iu_id;
73 __u8 rsvd1;
74 __be16 tag;
75 __be16 len;
76 __u8 status;
77 __u8 service_response;
78 __u8 sense[SCSI_SENSE_BUFFERSIZE];
81 enum {
82 CMD_PIPE_ID = 1,
83 STATUS_PIPE_ID = 2,
84 DATA_IN_PIPE_ID = 3,
85 DATA_OUT_PIPE_ID = 4,
87 UAS_SIMPLE_TAG = 0,
88 UAS_HEAD_TAG = 1,
89 UAS_ORDERED_TAG = 2,
90 UAS_ACA = 4,
93 struct uas_dev_info {
94 struct usb_interface *intf;
95 struct usb_device *udev;
96 int qdepth;
97 unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
98 unsigned use_streams:1;
99 unsigned uas_sense_old:1;
102 enum {
103 ALLOC_STATUS_URB = (1 << 0),
104 SUBMIT_STATUS_URB = (1 << 1),
105 ALLOC_DATA_IN_URB = (1 << 2),
106 SUBMIT_DATA_IN_URB = (1 << 3),
107 ALLOC_DATA_OUT_URB = (1 << 4),
108 SUBMIT_DATA_OUT_URB = (1 << 5),
109 ALLOC_CMD_URB = (1 << 6),
110 SUBMIT_CMD_URB = (1 << 7),
113 /* Overrides scsi_pointer */
114 struct uas_cmd_info {
115 unsigned int state;
116 unsigned int stream;
117 struct urb *cmd_urb;
118 struct urb *status_urb;
119 struct urb *data_in_urb;
120 struct urb *data_out_urb;
121 struct list_head list;
124 /* I hate forward declarations, but I actually have a loop */
125 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
126 struct uas_dev_info *devinfo, gfp_t gfp);
128 static DEFINE_SPINLOCK(uas_work_lock);
129 static LIST_HEAD(uas_work_list);
131 static void uas_do_work(struct work_struct *work)
133 struct uas_cmd_info *cmdinfo;
134 struct list_head list;
136 spin_lock_irq(&uas_work_lock);
137 list_replace_init(&uas_work_list, &list);
138 spin_unlock_irq(&uas_work_lock);
140 list_for_each_entry(cmdinfo, &list, list) {
141 struct scsi_pointer *scp = (void *)cmdinfo;
142 struct scsi_cmnd *cmnd = container_of(scp,
143 struct scsi_cmnd, SCp);
144 uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_NOIO);
148 static DECLARE_WORK(uas_work, uas_do_work);
150 static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
152 struct sense_iu *sense_iu = urb->transfer_buffer;
153 struct scsi_device *sdev = cmnd->device;
155 if (urb->actual_length > 16) {
156 unsigned len = be16_to_cpup(&sense_iu->len);
157 if (len + 16 != urb->actual_length) {
158 int newlen = min(len + 16, urb->actual_length) - 16;
159 if (newlen < 0)
160 newlen = 0;
161 sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
162 "disagrees with IU sense data length %d, "
163 "using %d bytes of sense data\n", __func__,
164 urb->actual_length, len, newlen);
165 len = newlen;
167 memcpy(cmnd->sense_buffer, sense_iu->sense, len);
170 cmnd->result = sense_iu->status;
171 if (sdev->current_cmnd)
172 sdev->current_cmnd = NULL;
173 cmnd->scsi_done(cmnd);
174 usb_free_urb(urb);
177 static void uas_sense_old(struct urb *urb, struct scsi_cmnd *cmnd)
179 struct sense_iu_old *sense_iu = urb->transfer_buffer;
180 struct scsi_device *sdev = cmnd->device;
182 if (urb->actual_length > 8) {
183 unsigned len = be16_to_cpup(&sense_iu->len) - 2;
184 if (len + 8 != urb->actual_length) {
185 int newlen = min(len + 8, urb->actual_length) - 8;
186 if (newlen < 0)
187 newlen = 0;
188 sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
189 "disagrees with IU sense data length %d, "
190 "using %d bytes of sense data\n", __func__,
191 urb->actual_length, len, newlen);
192 len = newlen;
194 memcpy(cmnd->sense_buffer, sense_iu->sense, len);
197 cmnd->result = sense_iu->status;
198 if (sdev->current_cmnd)
199 sdev->current_cmnd = NULL;
200 cmnd->scsi_done(cmnd);
201 usb_free_urb(urb);
204 static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
205 unsigned direction)
207 struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
208 int err;
210 cmdinfo->state = direction | SUBMIT_STATUS_URB;
211 err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
212 if (err) {
213 spin_lock(&uas_work_lock);
214 list_add_tail(&cmdinfo->list, &uas_work_list);
215 spin_unlock(&uas_work_lock);
216 schedule_work(&uas_work);
220 static void uas_stat_cmplt(struct urb *urb)
222 struct iu *iu = urb->transfer_buffer;
223 struct scsi_device *sdev = urb->context;
224 struct uas_dev_info *devinfo = sdev->hostdata;
225 struct scsi_cmnd *cmnd;
226 u16 tag;
228 if (urb->status) {
229 dev_err(&urb->dev->dev, "URB BAD STATUS %d\n", urb->status);
230 usb_free_urb(urb);
231 return;
234 tag = be16_to_cpup(&iu->tag) - 1;
235 if (sdev->current_cmnd)
236 cmnd = sdev->current_cmnd;
237 else
238 cmnd = scsi_find_tag(sdev, tag);
239 if (!cmnd)
240 return;
242 switch (iu->iu_id) {
243 case IU_ID_STATUS:
244 if (urb->actual_length < 16)
245 devinfo->uas_sense_old = 1;
246 if (devinfo->uas_sense_old)
247 uas_sense_old(urb, cmnd);
248 else
249 uas_sense(urb, cmnd);
250 break;
251 case IU_ID_READ_READY:
252 uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
253 break;
254 case IU_ID_WRITE_READY:
255 uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
256 break;
257 default:
258 scmd_printk(KERN_ERR, cmnd,
259 "Bogus IU (%d) received on status pipe\n", iu->iu_id);
263 static void uas_data_cmplt(struct urb *urb)
265 struct scsi_data_buffer *sdb = urb->context;
266 sdb->resid = sdb->length - urb->actual_length;
267 usb_free_urb(urb);
270 static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
271 unsigned int pipe, u16 stream_id,
272 struct scsi_data_buffer *sdb,
273 enum dma_data_direction dir)
275 struct usb_device *udev = devinfo->udev;
276 struct urb *urb = usb_alloc_urb(0, gfp);
278 if (!urb)
279 goto out;
280 usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length, uas_data_cmplt,
281 sdb);
282 if (devinfo->use_streams)
283 urb->stream_id = stream_id;
284 urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
285 urb->sg = sdb->table.sgl;
286 out:
287 return urb;
290 static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
291 struct scsi_cmnd *cmnd, u16 stream_id)
293 struct usb_device *udev = devinfo->udev;
294 struct urb *urb = usb_alloc_urb(0, gfp);
295 struct sense_iu *iu;
297 if (!urb)
298 goto out;
300 iu = kzalloc(sizeof(*iu), gfp);
301 if (!iu)
302 goto free;
304 usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
305 uas_stat_cmplt, cmnd->device);
306 urb->stream_id = stream_id;
307 urb->transfer_flags |= URB_FREE_BUFFER;
308 out:
309 return urb;
310 free:
311 usb_free_urb(urb);
312 return NULL;
315 static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
316 struct scsi_cmnd *cmnd, u16 stream_id)
318 struct usb_device *udev = devinfo->udev;
319 struct scsi_device *sdev = cmnd->device;
320 struct urb *urb = usb_alloc_urb(0, gfp);
321 struct command_iu *iu;
322 int len;
324 if (!urb)
325 goto out;
327 len = cmnd->cmd_len - 16;
328 if (len < 0)
329 len = 0;
330 len = ALIGN(len, 4);
331 iu = kzalloc(sizeof(*iu) + len, gfp);
332 if (!iu)
333 goto free;
335 iu->iu_id = IU_ID_COMMAND;
336 iu->tag = cpu_to_be16(stream_id);
337 iu->prio_attr = UAS_SIMPLE_TAG;
338 iu->len = len;
339 int_to_scsilun(sdev->lun, &iu->lun);
340 memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
342 usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
343 usb_free_urb, NULL);
344 urb->transfer_flags |= URB_FREE_BUFFER;
345 out:
346 return urb;
347 free:
348 usb_free_urb(urb);
349 return NULL;
353 * Why should I request the Status IU before sending the Command IU? Spec
354 * says to, but also says the device may receive them in any order. Seems
355 * daft to me.
358 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
359 struct uas_dev_info *devinfo, gfp_t gfp)
361 struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
363 if (cmdinfo->state & ALLOC_STATUS_URB) {
364 cmdinfo->status_urb = uas_alloc_sense_urb(devinfo, gfp, cmnd,
365 cmdinfo->stream);
366 if (!cmdinfo->status_urb)
367 return SCSI_MLQUEUE_DEVICE_BUSY;
368 cmdinfo->state &= ~ALLOC_STATUS_URB;
371 if (cmdinfo->state & SUBMIT_STATUS_URB) {
372 if (usb_submit_urb(cmdinfo->status_urb, gfp)) {
373 scmd_printk(KERN_INFO, cmnd,
374 "sense urb submission failure\n");
375 return SCSI_MLQUEUE_DEVICE_BUSY;
377 cmdinfo->state &= ~SUBMIT_STATUS_URB;
380 if (cmdinfo->state & ALLOC_DATA_IN_URB) {
381 cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, gfp,
382 devinfo->data_in_pipe, cmdinfo->stream,
383 scsi_in(cmnd), DMA_FROM_DEVICE);
384 if (!cmdinfo->data_in_urb)
385 return SCSI_MLQUEUE_DEVICE_BUSY;
386 cmdinfo->state &= ~ALLOC_DATA_IN_URB;
389 if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
390 if (usb_submit_urb(cmdinfo->data_in_urb, gfp)) {
391 scmd_printk(KERN_INFO, cmnd,
392 "data in urb submission failure\n");
393 return SCSI_MLQUEUE_DEVICE_BUSY;
395 cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
398 if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
399 cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, gfp,
400 devinfo->data_out_pipe, cmdinfo->stream,
401 scsi_out(cmnd), DMA_TO_DEVICE);
402 if (!cmdinfo->data_out_urb)
403 return SCSI_MLQUEUE_DEVICE_BUSY;
404 cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
407 if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
408 if (usb_submit_urb(cmdinfo->data_out_urb, gfp)) {
409 scmd_printk(KERN_INFO, cmnd,
410 "data out urb submission failure\n");
411 return SCSI_MLQUEUE_DEVICE_BUSY;
413 cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
416 if (cmdinfo->state & ALLOC_CMD_URB) {
417 cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, gfp, cmnd,
418 cmdinfo->stream);
419 if (!cmdinfo->cmd_urb)
420 return SCSI_MLQUEUE_DEVICE_BUSY;
421 cmdinfo->state &= ~ALLOC_CMD_URB;
424 if (cmdinfo->state & SUBMIT_CMD_URB) {
425 if (usb_submit_urb(cmdinfo->cmd_urb, gfp)) {
426 scmd_printk(KERN_INFO, cmnd,
427 "cmd urb submission failure\n");
428 return SCSI_MLQUEUE_DEVICE_BUSY;
430 cmdinfo->state &= ~SUBMIT_CMD_URB;
433 return 0;
436 static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
437 void (*done)(struct scsi_cmnd *))
439 struct scsi_device *sdev = cmnd->device;
440 struct uas_dev_info *devinfo = sdev->hostdata;
441 struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
442 int err;
444 BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
446 if (!cmdinfo->status_urb && sdev->current_cmnd)
447 return SCSI_MLQUEUE_DEVICE_BUSY;
449 if (blk_rq_tagged(cmnd->request)) {
450 cmdinfo->stream = cmnd->request->tag + 1;
451 } else {
452 sdev->current_cmnd = cmnd;
453 cmdinfo->stream = 1;
456 cmnd->scsi_done = done;
458 cmdinfo->state = ALLOC_STATUS_URB | SUBMIT_STATUS_URB |
459 ALLOC_CMD_URB | SUBMIT_CMD_URB;
461 switch (cmnd->sc_data_direction) {
462 case DMA_FROM_DEVICE:
463 cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
464 break;
465 case DMA_BIDIRECTIONAL:
466 cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
467 case DMA_TO_DEVICE:
468 cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
469 case DMA_NONE:
470 break;
473 if (!devinfo->use_streams) {
474 cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
475 cmdinfo->stream = 0;
478 err = uas_submit_urbs(cmnd, devinfo, GFP_ATOMIC);
479 if (err) {
480 /* If we did nothing, give up now */
481 if (cmdinfo->state & SUBMIT_STATUS_URB) {
482 usb_free_urb(cmdinfo->status_urb);
483 return SCSI_MLQUEUE_DEVICE_BUSY;
485 spin_lock(&uas_work_lock);
486 list_add_tail(&cmdinfo->list, &uas_work_list);
487 spin_unlock(&uas_work_lock);
488 schedule_work(&uas_work);
491 return 0;
494 static DEF_SCSI_QCMD(uas_queuecommand)
496 static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
498 struct scsi_device *sdev = cmnd->device;
499 sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
500 cmnd->request->tag);
502 /* XXX: Send ABORT TASK Task Management command */
503 return FAILED;
506 static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
508 struct scsi_device *sdev = cmnd->device;
509 sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
510 cmnd->request->tag);
512 /* XXX: Send LOGICAL UNIT RESET Task Management command */
513 return FAILED;
516 static int uas_eh_target_reset_handler(struct scsi_cmnd *cmnd)
518 struct scsi_device *sdev = cmnd->device;
519 sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
520 cmnd->request->tag);
522 /* XXX: Can we reset just the one USB interface?
523 * Would calling usb_set_interface() have the right effect?
525 return FAILED;
528 static int uas_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
530 struct scsi_device *sdev = cmnd->device;
531 struct uas_dev_info *devinfo = sdev->hostdata;
532 struct usb_device *udev = devinfo->udev;
534 sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
535 cmnd->request->tag);
537 if (usb_reset_device(udev))
538 return SUCCESS;
540 return FAILED;
543 static int uas_slave_alloc(struct scsi_device *sdev)
545 sdev->hostdata = (void *)sdev->host->hostdata[0];
546 return 0;
549 static int uas_slave_configure(struct scsi_device *sdev)
551 struct uas_dev_info *devinfo = sdev->hostdata;
552 scsi_set_tag_type(sdev, MSG_ORDERED_TAG);
553 scsi_activate_tcq(sdev, devinfo->qdepth - 1);
554 return 0;
557 static struct scsi_host_template uas_host_template = {
558 .module = THIS_MODULE,
559 .name = "uas",
560 .queuecommand = uas_queuecommand,
561 .slave_alloc = uas_slave_alloc,
562 .slave_configure = uas_slave_configure,
563 .eh_abort_handler = uas_eh_abort_handler,
564 .eh_device_reset_handler = uas_eh_device_reset_handler,
565 .eh_target_reset_handler = uas_eh_target_reset_handler,
566 .eh_bus_reset_handler = uas_eh_bus_reset_handler,
567 .can_queue = 65536, /* Is there a limit on the _host_ ? */
568 .this_id = -1,
569 .sg_tablesize = SG_NONE,
570 .cmd_per_lun = 1, /* until we override it */
571 .skip_settle_delay = 1,
572 .ordered_tag = 1,
575 static struct usb_device_id uas_usb_ids[] = {
576 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
577 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
578 /* 0xaa is a prototype device I happen to have access to */
579 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, 0xaa) },
582 MODULE_DEVICE_TABLE(usb, uas_usb_ids);
584 static int uas_is_interface(struct usb_host_interface *intf)
586 return (intf->desc.bInterfaceClass == USB_CLASS_MASS_STORAGE &&
587 intf->desc.bInterfaceSubClass == USB_SC_SCSI &&
588 intf->desc.bInterfaceProtocol == USB_PR_UAS);
591 static int uas_switch_interface(struct usb_device *udev,
592 struct usb_interface *intf)
594 int i;
596 if (uas_is_interface(intf->cur_altsetting))
597 return 0;
599 for (i = 0; i < intf->num_altsetting; i++) {
600 struct usb_host_interface *alt = &intf->altsetting[i];
601 if (alt == intf->cur_altsetting)
602 continue;
603 if (uas_is_interface(alt))
604 return usb_set_interface(udev,
605 alt->desc.bInterfaceNumber,
606 alt->desc.bAlternateSetting);
609 return -ENODEV;
612 static void uas_configure_endpoints(struct uas_dev_info *devinfo)
614 struct usb_host_endpoint *eps[4] = { };
615 struct usb_interface *intf = devinfo->intf;
616 struct usb_device *udev = devinfo->udev;
617 struct usb_host_endpoint *endpoint = intf->cur_altsetting->endpoint;
618 unsigned i, n_endpoints = intf->cur_altsetting->desc.bNumEndpoints;
620 devinfo->uas_sense_old = 0;
622 for (i = 0; i < n_endpoints; i++) {
623 unsigned char *extra = endpoint[i].extra;
624 int len = endpoint[i].extralen;
625 while (len > 1) {
626 if (extra[1] == USB_DT_PIPE_USAGE) {
627 unsigned pipe_id = extra[2];
628 if (pipe_id > 0 && pipe_id < 5)
629 eps[pipe_id - 1] = &endpoint[i];
630 break;
632 len -= extra[0];
633 extra += extra[0];
638 * Assume that if we didn't find a control pipe descriptor, we're
639 * using a device with old firmware that happens to be set up like
640 * this.
642 if (!eps[0]) {
643 devinfo->cmd_pipe = usb_sndbulkpipe(udev, 1);
644 devinfo->status_pipe = usb_rcvbulkpipe(udev, 1);
645 devinfo->data_in_pipe = usb_rcvbulkpipe(udev, 2);
646 devinfo->data_out_pipe = usb_sndbulkpipe(udev, 2);
648 eps[1] = usb_pipe_endpoint(udev, devinfo->status_pipe);
649 eps[2] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
650 eps[3] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
651 } else {
652 devinfo->cmd_pipe = usb_sndbulkpipe(udev,
653 eps[0]->desc.bEndpointAddress);
654 devinfo->status_pipe = usb_rcvbulkpipe(udev,
655 eps[1]->desc.bEndpointAddress);
656 devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
657 eps[2]->desc.bEndpointAddress);
658 devinfo->data_out_pipe = usb_sndbulkpipe(udev,
659 eps[3]->desc.bEndpointAddress);
662 devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1, 3, 256,
663 GFP_KERNEL);
664 if (devinfo->qdepth < 0) {
665 devinfo->qdepth = 256;
666 devinfo->use_streams = 0;
667 } else {
668 devinfo->use_streams = 1;
673 * XXX: What I'd like to do here is register a SCSI host for each USB host in
674 * the system. Follow usb-storage's design of registering a SCSI host for
675 * each USB device for the moment. Can implement this by walking up the
676 * USB hierarchy until we find a USB host.
678 static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
680 int result;
681 struct Scsi_Host *shost;
682 struct uas_dev_info *devinfo;
683 struct usb_device *udev = interface_to_usbdev(intf);
685 if (uas_switch_interface(udev, intf))
686 return -ENODEV;
688 devinfo = kmalloc(sizeof(struct uas_dev_info), GFP_KERNEL);
689 if (!devinfo)
690 return -ENOMEM;
692 result = -ENOMEM;
693 shost = scsi_host_alloc(&uas_host_template, sizeof(void *));
694 if (!shost)
695 goto free;
697 shost->max_cmd_len = 16 + 252;
698 shost->max_id = 1;
699 shost->sg_tablesize = udev->bus->sg_tablesize;
701 result = scsi_add_host(shost, &intf->dev);
702 if (result)
703 goto free;
704 shost->hostdata[0] = (unsigned long)devinfo;
706 devinfo->intf = intf;
707 devinfo->udev = udev;
708 uas_configure_endpoints(devinfo);
710 scsi_scan_host(shost);
711 usb_set_intfdata(intf, shost);
712 return result;
713 free:
714 kfree(devinfo);
715 if (shost)
716 scsi_host_put(shost);
717 return result;
720 static int uas_pre_reset(struct usb_interface *intf)
722 /* XXX: Need to return 1 if it's not our device in error handling */
723 return 0;
726 static int uas_post_reset(struct usb_interface *intf)
728 /* XXX: Need to return 1 if it's not our device in error handling */
729 return 0;
732 static void uas_disconnect(struct usb_interface *intf)
734 struct usb_device *udev = interface_to_usbdev(intf);
735 struct usb_host_endpoint *eps[3];
736 struct Scsi_Host *shost = usb_get_intfdata(intf);
737 struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
739 scsi_remove_host(shost);
741 eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
742 eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
743 eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
744 usb_free_streams(intf, eps, 3, GFP_KERNEL);
746 kfree(devinfo);
750 * XXX: Should this plug into libusual so we can auto-upgrade devices from
751 * Bulk-Only to UAS?
753 static struct usb_driver uas_driver = {
754 .name = "uas",
755 .probe = uas_probe,
756 .disconnect = uas_disconnect,
757 .pre_reset = uas_pre_reset,
758 .post_reset = uas_post_reset,
759 .id_table = uas_usb_ids,
762 static int uas_init(void)
764 return usb_register(&uas_driver);
767 static void uas_exit(void)
769 usb_deregister(&uas_driver);
772 module_init(uas_init);
773 module_exit(uas_exit);
775 MODULE_LICENSE("GPL");
776 MODULE_AUTHOR("Matthew Wilcox and Sarah Sharp");