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gpio: Add TC35892 GPIO driver
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / block / ub.c
blob0536b5b29adcb02ff76c4fcf8b4501668220a6d3
1 /*
2 * The low performance USB storage driver (ub).
3 *
4 * Copyright (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
5 * Copyright (C) 2004 Pete Zaitcev (zaitcev@yahoo.com)
6 *
7 * This work is a part of Linux kernel, is derived from it,
8 * and is not licensed separately. See file COPYING for details.
9 *
10 * TODO (sorted by decreasing priority)
11 * -- Return sense now that rq allows it (we always auto-sense anyway).
12 * -- set readonly flag for CDs, set removable flag for CF readers
13 * -- do inquiry and verify we got a disk and not a tape (for LUN mismatch)
14 * -- verify the 13 conditions and do bulk resets
15 * -- highmem
16 * -- move top_sense and work_bcs into separate allocations (if they survive)
17 * for cache purists and esoteric architectures.
18 * -- Allocate structure for LUN 0 before the first ub_sync_tur, avoid NULL. ?
19 * -- prune comments, they are too volumnous
20 * -- Resove XXX's
21 * -- CLEAR, CLR2STS, CLRRS seem to be ripe for refactoring.
22 */
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/usb.h>
26 #include <linux/usb_usual.h>
27 #include <linux/blkdev.h>
28 #include <linux/timer.h>
29 #include <linux/scatterlist.h>
30 #include <linux/slab.h>
31 #include <scsi/scsi.h>
32
33 #define DRV_NAME "ub"
34
35 #define UB_MAJOR 180
36
37 /*
38 * The command state machine is the key model for understanding of this driver.
39 *
40 * The general rule is that all transitions are done towards the bottom
41 * of the diagram, thus preventing any loops.
42 *
43 * An exception to that is how the STAT state is handled. A counter allows it
44 * to be re-entered along the path marked with [C].
45 *
46 * +--------+
47 * ! INIT !
48 * +--------+
49 * !
50 * ub_scsi_cmd_start fails ->--------------------------------------\
51 * ! !
52 * V !
53 * +--------+ !
54 * ! CMD ! !
55 * +--------+ !
56 * ! +--------+ !
57 * was -EPIPE -->-------------------------------->! CLEAR ! !
58 * ! +--------+ !
59 * ! ! !
60 * was error -->------------------------------------- ! --------->\
61 * ! ! !
62 * /--<-- cmd->dir == NONE ? ! !
63 * ! ! ! !
64 * ! V ! !
65 * ! +--------+ ! !
66 * ! ! DATA ! ! !
67 * ! +--------+ ! !
68 * ! ! +---------+ ! !
69 * ! was -EPIPE -->--------------->! CLR2STS ! ! !
70 * ! ! +---------+ ! !
71 * ! ! ! ! !
72 * ! ! was error -->---- ! --------->\
73 * ! was error -->--------------------- ! ------------- ! --------->\
74 * ! ! ! ! !
75 * ! V ! ! !
76 * \--->+--------+ ! ! !
77 * ! STAT !<--------------------------/ ! !
78 * /--->+--------+ ! !
79 * ! ! ! !
80 * [C] was -EPIPE -->-----------\ ! !
81 * ! ! ! ! !
82 * +<---- len == 0 ! ! !
83 * ! ! ! ! !
84 * ! was error -->--------------------------------------!---------->\
85 * ! ! ! ! !
86 * +<---- bad CSW ! ! !
87 * +<---- bad tag ! ! !
88 * ! ! V ! !
89 * ! ! +--------+ ! !
90 * ! ! ! CLRRS ! ! !
91 * ! ! +--------+ ! !
92 * ! ! ! ! !
93 * \------- ! --------------------[C]--------\ ! !
94 * ! ! ! !
95 * cmd->error---\ +--------+ ! !
96 * ! +--------------->! SENSE !<----------/ !
97 * STAT_FAIL----/ +--------+ !
98 * ! ! V
99 * ! V +--------+
100 * \--------------------------------\--------------------->! DONE !
101 * +--------+
102 */
103
104 /*
105 * This many LUNs per USB device.
106 * Every one of them takes a host, see UB_MAX_HOSTS.
107 */
108 #define UB_MAX_LUNS 9
109
110 /*
111 */
112
113 #define UB_PARTS_PER_LUN 8
114
115 #define UB_MAX_CDB_SIZE 16 /* Corresponds to Bulk */
116
117 #define UB_SENSE_SIZE 18
118
119 /*
120 */
121
122 /* command block wrapper */
123 struct bulk_cb_wrap {
124 __le32 Signature; /* contains 'USBC' */
125 u32 Tag; /* unique per command id */
126 __le32 DataTransferLength; /* size of data */
127 u8 Flags; /* direction in bit 0 */
128 u8 Lun; /* LUN */
129 u8 Length; /* of of the CDB */
130 u8 CDB[UB_MAX_CDB_SIZE]; /* max command */
131 };
132
133 #define US_BULK_CB_WRAP_LEN 31
134 #define US_BULK_CB_SIGN 0x43425355 /*spells out USBC */
135 #define US_BULK_FLAG_IN 1
136 #define US_BULK_FLAG_OUT 0
137
138 /* command status wrapper */
139 struct bulk_cs_wrap {
140 __le32 Signature; /* should = 'USBS' */
141 u32 Tag; /* same as original command */
142 __le32 Residue; /* amount not transferred */
143 u8 Status; /* see below */
144 };
145
146 #define US_BULK_CS_WRAP_LEN 13
147 #define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */
148 #define US_BULK_STAT_OK 0
149 #define US_BULK_STAT_FAIL 1
150 #define US_BULK_STAT_PHASE 2
151
152 /* bulk-only class specific requests */
153 #define US_BULK_RESET_REQUEST 0xff
154 #define US_BULK_GET_MAX_LUN 0xfe
155
156 /*
157 */
158 struct ub_dev;
159
160 #define UB_MAX_REQ_SG 9 /* cdrecord requires 32KB and maybe a header */
161 #define UB_MAX_SECTORS 64
162
163 /*
164 * A second is more than enough for a 32K transfer (UB_MAX_SECTORS)
165 * even if a webcam hogs the bus, but some devices need time to spin up.
166 */
167 #define UB_URB_TIMEOUT (HZ*2)
168 #define UB_DATA_TIMEOUT (HZ*5) /* ZIP does spin-ups in the data phase */
169 #define UB_STAT_TIMEOUT (HZ*5) /* Same spinups and eject for a dataless cmd. */
170 #define UB_CTRL_TIMEOUT (HZ/2) /* 500ms ought to be enough to clear a stall */
171
172 /*
173 * An instance of a SCSI command in transit.
174 */
175 #define UB_DIR_NONE 0
176 #define UB_DIR_READ 1
177 #define UB_DIR_ILLEGAL2 2
178 #define UB_DIR_WRITE 3
179
180 #define UB_DIR_CHAR(c) (((c)==UB_DIR_WRITE)? 'w': \
181 (((c)==UB_DIR_READ)? 'r': 'n'))
182
183 enum ub_scsi_cmd_state {
184 UB_CMDST_INIT, /* Initial state */
185 UB_CMDST_CMD, /* Command submitted */
186 UB_CMDST_DATA, /* Data phase */
187 UB_CMDST_CLR2STS, /* Clearing before requesting status */
188 UB_CMDST_STAT, /* Status phase */
189 UB_CMDST_CLEAR, /* Clearing a stall (halt, actually) */
190 UB_CMDST_CLRRS, /* Clearing before retrying status */
191 UB_CMDST_SENSE, /* Sending Request Sense */
192 UB_CMDST_DONE /* Final state */
193 };
194
195 struct ub_scsi_cmd {
196 unsigned char cdb[UB_MAX_CDB_SIZE];
197 unsigned char cdb_len;
198
199 unsigned char dir; /* 0 - none, 1 - read, 3 - write. */
200 enum ub_scsi_cmd_state state;
201 unsigned int tag;
202 struct ub_scsi_cmd *next;
203
204 int error; /* Return code - valid upon done */
205 unsigned int act_len; /* Return size */
206 unsigned char key, asc, ascq; /* May be valid if error==-EIO */
207
208 int stat_count; /* Retries getting status. */
209 unsigned int timeo; /* jiffies until rq->timeout changes */
210
211 unsigned int len; /* Requested length */
212 unsigned int current_sg;
213 unsigned int nsg; /* sgv[nsg] */
214 struct scatterlist sgv[UB_MAX_REQ_SG];
215
216 struct ub_lun *lun;
217 void (*done)(struct ub_dev *, struct ub_scsi_cmd *);
218 void *back;
219 };
220
221 struct ub_request {
222 struct request *rq;
223 unsigned int current_try;
224 unsigned int nsg; /* sgv[nsg] */
225 struct scatterlist sgv[UB_MAX_REQ_SG];
226 };
227
228 /*
229 */
230 struct ub_capacity {
231 unsigned long nsec; /* Linux size - 512 byte sectors */
232 unsigned int bsize; /* Linux hardsect_size */
233 unsigned int bshift; /* Shift between 512 and hard sects */
234 };
235
236 /*
237 * This is a direct take-off from linux/include/completion.h
238 * The difference is that I do not wait on this thing, just poll.
239 * When I want to wait (ub_probe), I just use the stock completion.
240 *
241 * Note that INIT_COMPLETION takes no lock. It is correct. But why
242 * in the bloody hell that thing takes struct instead of pointer to struct
243 * is quite beyond me. I just copied it from the stock completion.
244 */
245 struct ub_completion {
246 unsigned int done;
247 spinlock_t lock;
248 };
249
250 static inline void ub_init_completion(struct ub_completion *x)
251 {
252 x->done = 0;
253 spin_lock_init(&x->lock);
254 }
255
256 #define UB_INIT_COMPLETION(x) ((x).done = 0)
257
258 static void ub_complete(struct ub_completion *x)
259 {
260 unsigned long flags;
261
262 spin_lock_irqsave(&x->lock, flags);
263 x->done++;
264 spin_unlock_irqrestore(&x->lock, flags);
265 }
266
267 static int ub_is_completed(struct ub_completion *x)
268 {
269 unsigned long flags;
270 int ret;
271
272 spin_lock_irqsave(&x->lock, flags);
273 ret = x->done;
274 spin_unlock_irqrestore(&x->lock, flags);
275 return ret;
276 }
277
278 /*
279 */
280 struct ub_scsi_cmd_queue {
281 int qlen, qmax;
282 struct ub_scsi_cmd *head, *tail;
283 };
284
285 /*
286 * The block device instance (one per LUN).
287 */
288 struct ub_lun {
289 struct ub_dev *udev;
290 struct list_head link;
291 struct gendisk *disk;
292 int id; /* Host index */
293 int num; /* LUN number */
294 char name[16];
295
296 int changed; /* Media was changed */
297 int removable;
298 int readonly;
299
300 struct ub_request urq;
301
302 /* Use Ingo's mempool if or when we have more than one command. */
303 /*
304 * Currently we never need more than one command for the whole device.
305 * However, giving every LUN a command is a cheap and automatic way
306 * to enforce fairness between them.
307 */
308 int cmda[1];
309 struct ub_scsi_cmd cmdv[1];
310
311 struct ub_capacity capacity;
312 };
313
314 /*
315 * The USB device instance.
316 */
317 struct ub_dev {
318 spinlock_t *lock;
319 atomic_t poison; /* The USB device is disconnected */
320 int openc; /* protected by ub_lock! */
321 /* kref is too implicit for our taste */
322 int reset; /* Reset is running */
323 int bad_resid;
324 unsigned int tagcnt;
325 char name[12];
326 struct usb_device *dev;
327 struct usb_interface *intf;
328
329 struct list_head luns;
330
331 unsigned int send_bulk_pipe; /* cached pipe values */
332 unsigned int recv_bulk_pipe;
333 unsigned int send_ctrl_pipe;
334 unsigned int recv_ctrl_pipe;
335
336 struct tasklet_struct tasklet;
337
338 struct ub_scsi_cmd_queue cmd_queue;
339 struct ub_scsi_cmd top_rqs_cmd; /* REQUEST SENSE */
340 unsigned char top_sense[UB_SENSE_SIZE];
341
342 struct ub_completion work_done;
343 struct urb work_urb;
344 struct timer_list work_timer;
345 int last_pipe; /* What might need clearing */
346 __le32 signature; /* Learned signature */
347 struct bulk_cb_wrap work_bcb;
348 struct bulk_cs_wrap work_bcs;
349 struct usb_ctrlrequest work_cr;
350
351 struct work_struct reset_work;
352 wait_queue_head_t reset_wait;
353 };
354
355 /*
356 */
357 static void ub_cleanup(struct ub_dev *sc);
358 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq);
359 static void ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
360 struct ub_scsi_cmd *cmd, struct ub_request *urq);
361 static void ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
362 struct ub_scsi_cmd *cmd, struct ub_request *urq);
363 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
364 static void ub_end_rq(struct request *rq, unsigned int status);
365 static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
366 struct ub_request *urq, struct ub_scsi_cmd *cmd);
367 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
368 static void ub_urb_complete(struct urb *urb);
369 static void ub_scsi_action(unsigned long _dev);
370 static void ub_scsi_dispatch(struct ub_dev *sc);
371 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
372 static void ub_data_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
373 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc);
374 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
375 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
376 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
377 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
378 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
379 int stalled_pipe);
380 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd);
381 static void ub_reset_enter(struct ub_dev *sc, int try);
382 static void ub_reset_task(struct work_struct *work);
383 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun);
384 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
385 struct ub_capacity *ret);
386 static int ub_sync_reset(struct ub_dev *sc);
387 static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe);
388 static int ub_probe_lun(struct ub_dev *sc, int lnum);
389
390 /*
391 */
392 #ifdef CONFIG_USB_LIBUSUAL
393
394 #define ub_usb_ids usb_storage_usb_ids
395 #else
396
397 static const struct usb_device_id ub_usb_ids[] = {
398 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_BULK) },
399 { }
400 };
401
402 MODULE_DEVICE_TABLE(usb, ub_usb_ids);
403 #endif /* CONFIG_USB_LIBUSUAL */
404
405 /*
406 * Find me a way to identify "next free minor" for add_disk(),
407 * and the array disappears the next day. However, the number of
408 * hosts has something to do with the naming and /proc/partitions.
409 * This has to be thought out in detail before changing.
410 * If UB_MAX_HOST was 1000, we'd use a bitmap. Or a better data structure.
411 */
412 #define UB_MAX_HOSTS 26
413 static char ub_hostv[UB_MAX_HOSTS];
414
415 #define UB_QLOCK_NUM 5
416 static spinlock_t ub_qlockv[UB_QLOCK_NUM];
417 static int ub_qlock_next = 0;
418
419 static DEFINE_SPINLOCK(ub_lock); /* Locks globals and ->openc */
420
421 /*
422 * The id allocator.
423 *
424 * This also stores the host for indexing by minor, which is somewhat dirty.
425 */
426 static int ub_id_get(void)
427 {
428 unsigned long flags;
429 int i;
430
431 spin_lock_irqsave(&ub_lock, flags);
432 for (i = 0; i < UB_MAX_HOSTS; i++) {
433 if (ub_hostv[i] == 0) {
434 ub_hostv[i] = 1;
435 spin_unlock_irqrestore(&ub_lock, flags);
436 return i;
437 }
438 }
439 spin_unlock_irqrestore(&ub_lock, flags);
440 return -1;
441 }
442
443 static void ub_id_put(int id)
444 {
445 unsigned long flags;
446
447 if (id < 0 || id >= UB_MAX_HOSTS) {
448 printk(KERN_ERR DRV_NAME ": bad host ID %d\n", id);
449 return;
450 }
451
452 spin_lock_irqsave(&ub_lock, flags);
453 if (ub_hostv[id] == 0) {
454 spin_unlock_irqrestore(&ub_lock, flags);
455 printk(KERN_ERR DRV_NAME ": freeing free host ID %d\n", id);
456 return;
457 }
458 ub_hostv[id] = 0;
459 spin_unlock_irqrestore(&ub_lock, flags);
460 }
461
462 /*
463 * This is necessitated by the fact that blk_cleanup_queue does not
464 * necesserily destroy the queue. Instead, it may merely decrease q->refcnt.
465 * Since our blk_init_queue() passes a spinlock common with ub_dev,
466 * we have life time issues when ub_cleanup frees ub_dev.
467 */
468 static spinlock_t *ub_next_lock(void)
469 {
470 unsigned long flags;
471 spinlock_t *ret;
472
473 spin_lock_irqsave(&ub_lock, flags);
474 ret = &ub_qlockv[ub_qlock_next];
475 ub_qlock_next = (ub_qlock_next + 1) % UB_QLOCK_NUM;
476 spin_unlock_irqrestore(&ub_lock, flags);
477 return ret;
478 }
479
480 /*
481 * Downcount for deallocation. This rides on two assumptions:
482 * - once something is poisoned, its refcount cannot grow
483 * - opens cannot happen at this time (del_gendisk was done)
484 * If the above is true, we can drop the lock, which we need for
485 * blk_cleanup_queue(): the silly thing may attempt to sleep.
486 * [Actually, it never needs to sleep for us, but it calls might_sleep()]
487 */
488 static void ub_put(struct ub_dev *sc)
489 {
490 unsigned long flags;
491
492 spin_lock_irqsave(&ub_lock, flags);
493 --sc->openc;
494 if (sc->openc == 0 && atomic_read(&sc->poison)) {
495 spin_unlock_irqrestore(&ub_lock, flags);
496 ub_cleanup(sc);
497 } else {
498 spin_unlock_irqrestore(&ub_lock, flags);
499 }
500 }
501
502 /*
503 * Final cleanup and deallocation.
504 */
505 static void ub_cleanup(struct ub_dev *sc)
506 {
507 struct list_head *p;
508 struct ub_lun *lun;
509 struct request_queue *q;
510
511 while (!list_empty(&sc->luns)) {
512 p = sc->luns.next;
513 lun = list_entry(p, struct ub_lun, link);
514 list_del(p);
515
516 /* I don't think queue can be NULL. But... Stolen from sx8.c */
517 if ((q = lun->disk->queue) != NULL)
518 blk_cleanup_queue(q);
519 /*
520 * If we zero disk->private_data BEFORE put_disk, we have
521 * to check for NULL all over the place in open, release,
522 * check_media and revalidate, because the block level
523 * semaphore is well inside the put_disk.
524 * But we cannot zero after the call, because *disk is gone.
525 * The sd.c is blatantly racy in this area.
526 */
527 /* disk->private_data = NULL; */
528 put_disk(lun->disk);
529 lun->disk = NULL;
530
531 ub_id_put(lun->id);
532 kfree(lun);
533 }
534
535 usb_set_intfdata(sc->intf, NULL);
536 usb_put_intf(sc->intf);
537 usb_put_dev(sc->dev);
538 kfree(sc);
539 }
540
541 /*
542 * The "command allocator".
543 */
544 static struct ub_scsi_cmd *ub_get_cmd(struct ub_lun *lun)
545 {
546 struct ub_scsi_cmd *ret;
547
548 if (lun->cmda[0])
549 return NULL;
550 ret = &lun->cmdv[0];
551 lun->cmda[0] = 1;
552 return ret;
553 }
554
555 static void ub_put_cmd(struct ub_lun *lun, struct ub_scsi_cmd *cmd)
556 {
557 if (cmd != &lun->cmdv[0]) {
558 printk(KERN_WARNING "%s: releasing a foreign cmd %p\n",
559 lun->name, cmd);
560 return;
561 }
562 if (!lun->cmda[0]) {
563 printk(KERN_WARNING "%s: releasing a free cmd\n", lun->name);
564 return;
565 }
566 lun->cmda[0] = 0;
567 }
568
569 /*
570 * The command queue.
571 */
572 static void ub_cmdq_add(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
573 {
574 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
575
576 if (t->qlen++ == 0) {
577 t->head = cmd;
578 t->tail = cmd;
579 } else {
580 t->tail->next = cmd;
581 t->tail = cmd;
582 }
583
584 if (t->qlen > t->qmax)
585 t->qmax = t->qlen;
586 }
587
588 static void ub_cmdq_insert(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
589 {
590 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
591
592 if (t->qlen++ == 0) {
593 t->head = cmd;
594 t->tail = cmd;
595 } else {
596 cmd->next = t->head;
597 t->head = cmd;
598 }
599
600 if (t->qlen > t->qmax)
601 t->qmax = t->qlen;
602 }
603
604 static struct ub_scsi_cmd *ub_cmdq_pop(struct ub_dev *sc)
605 {
606 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
607 struct ub_scsi_cmd *cmd;
608
609 if (t->qlen == 0)
610 return NULL;
611 if (--t->qlen == 0)
612 t->tail = NULL;
613 cmd = t->head;
614 t->head = cmd->next;
615 cmd->next = NULL;
616 return cmd;
617 }
618
619 #define ub_cmdq_peek(sc) ((sc)->cmd_queue.head)
620
621 /*
622 * The request function is our main entry point
623 */
624
625 static void ub_request_fn(struct request_queue *q)
626 {
627 struct ub_lun *lun = q->queuedata;
628 struct request *rq;
629
630 while ((rq = blk_peek_request(q)) != NULL) {
631 if (ub_request_fn_1(lun, rq) != 0) {
632 blk_stop_queue(q);
633 break;
634 }
635 }
636 }
637
638 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq)
639 {
640 struct ub_dev *sc = lun->udev;
641 struct ub_scsi_cmd *cmd;
642 struct ub_request *urq;
643 int n_elem;
644
645 if (atomic_read(&sc->poison)) {
646 blk_start_request(rq);
647 ub_end_rq(rq, DID_NO_CONNECT << 16);
648 return 0;
649 }
650
651 if (lun->changed && !blk_pc_request(rq)) {
652 blk_start_request(rq);
653 ub_end_rq(rq, SAM_STAT_CHECK_CONDITION);
654 return 0;
655 }
656
657 if (lun->urq.rq != NULL)
658 return -1;
659 if ((cmd = ub_get_cmd(lun)) == NULL)
660 return -1;
661 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
662
663 blk_start_request(rq);
664
665 urq = &lun->urq;
666 memset(urq, 0, sizeof(struct ub_request));
667 urq->rq = rq;
668
669 /*
670 * get scatterlist from block layer
671 */
672 sg_init_table(&urq->sgv[0], UB_MAX_REQ_SG);
673 n_elem = blk_rq_map_sg(lun->disk->queue, rq, &urq->sgv[0]);
674 if (n_elem < 0) {
675 /* Impossible, because blk_rq_map_sg should not hit ENOMEM. */
676 printk(KERN_INFO "%s: failed request map (%d)\n",
677 lun->name, n_elem);
678 goto drop;
679 }
680 if (n_elem > UB_MAX_REQ_SG) { /* Paranoia */
681 printk(KERN_WARNING "%s: request with %d segments\n",
682 lun->name, n_elem);
683 goto drop;
684 }
685 urq->nsg = n_elem;
686
687 if (blk_pc_request(rq)) {
688 ub_cmd_build_packet(sc, lun, cmd, urq);
689 } else {
690 ub_cmd_build_block(sc, lun, cmd, urq);
691 }
692 cmd->state = UB_CMDST_INIT;
693 cmd->lun = lun;
694 cmd->done = ub_rw_cmd_done;
695 cmd->back = urq;
696
697 cmd->tag = sc->tagcnt++;
698 if (ub_submit_scsi(sc, cmd) != 0)
699 goto drop;
700
701 return 0;
702
703 drop:
704 ub_put_cmd(lun, cmd);
705 ub_end_rq(rq, DID_ERROR << 16);
706 return 0;
707 }
708
709 static void ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
710 struct ub_scsi_cmd *cmd, struct ub_request *urq)
711 {
712 struct request *rq = urq->rq;
713 unsigned int block, nblks;
714
715 if (rq_data_dir(rq) == WRITE)
716 cmd->dir = UB_DIR_WRITE;
717 else
718 cmd->dir = UB_DIR_READ;
719
720 cmd->nsg = urq->nsg;
721 memcpy(cmd->sgv, urq->sgv, sizeof(struct scatterlist) * cmd->nsg);
722
723 /*
724 * build the command
725 *
726 * The call to blk_queue_logical_block_size() guarantees that request
727 * is aligned, but it is given in terms of 512 byte units, always.
728 */
729 block = blk_rq_pos(rq) >> lun->capacity.bshift;
730 nblks = blk_rq_sectors(rq) >> lun->capacity.bshift;
731
732 cmd->cdb[0] = (cmd->dir == UB_DIR_READ)? READ_10: WRITE_10;
733 /* 10-byte uses 4 bytes of LBA: 2147483648KB, 2097152MB, 2048GB */
734 cmd->cdb[2] = block >> 24;
735 cmd->cdb[3] = block >> 16;
736 cmd->cdb[4] = block >> 8;
737 cmd->cdb[5] = block;
738 cmd->cdb[7] = nblks >> 8;
739 cmd->cdb[8] = nblks;
740 cmd->cdb_len = 10;
741
742 cmd->len = blk_rq_bytes(rq);
743 }
744
745 static void ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
746 struct ub_scsi_cmd *cmd, struct ub_request *urq)
747 {
748 struct request *rq = urq->rq;
749
750 if (blk_rq_bytes(rq) == 0) {
751 cmd->dir = UB_DIR_NONE;
752 } else {
753 if (rq_data_dir(rq) == WRITE)
754 cmd->dir = UB_DIR_WRITE;
755 else
756 cmd->dir = UB_DIR_READ;
757 }
758
759 cmd->nsg = urq->nsg;
760 memcpy(cmd->sgv, urq->sgv, sizeof(struct scatterlist) * cmd->nsg);
761
762 memcpy(&cmd->cdb, rq->cmd, rq->cmd_len);
763 cmd->cdb_len = rq->cmd_len;
764
765 cmd->len = blk_rq_bytes(rq);
766
767 /*
768 * To reapply this to every URB is not as incorrect as it looks.
769 * In return, we avoid any complicated tracking calculations.
770 */
771 cmd->timeo = rq->timeout;
772 }
773
774 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
775 {
776 struct ub_lun *lun = cmd->lun;
777 struct ub_request *urq = cmd->back;
778 struct request *rq;
779 unsigned int scsi_status;
780
781 rq = urq->rq;
782
783 if (cmd->error == 0) {
784 if (blk_pc_request(rq)) {
785 if (cmd->act_len >= rq->resid_len)
786 rq->resid_len = 0;
787 else
788 rq->resid_len -= cmd->act_len;
789 scsi_status = 0;
790 } else {
791 if (cmd->act_len != cmd->len) {
792 scsi_status = SAM_STAT_CHECK_CONDITION;
793 } else {
794 scsi_status = 0;
795 }
796 }
797 } else {
798 if (blk_pc_request(rq)) {
799 /* UB_SENSE_SIZE is smaller than SCSI_SENSE_BUFFERSIZE */
800 memcpy(rq->sense, sc->top_sense, UB_SENSE_SIZE);
801 rq->sense_len = UB_SENSE_SIZE;
802 if (sc->top_sense[0] != 0)
803 scsi_status = SAM_STAT_CHECK_CONDITION;
804 else
805 scsi_status = DID_ERROR << 16;
806 } else {
807 if (cmd->error == -EIO &&
808 (cmd->key == 0 ||
809 cmd->key == MEDIUM_ERROR ||
810 cmd->key == UNIT_ATTENTION)) {
811 if (ub_rw_cmd_retry(sc, lun, urq, cmd) == 0)
812 return;
813 }
814 scsi_status = SAM_STAT_CHECK_CONDITION;
815 }
816 }
817
818 urq->rq = NULL;
819
820 ub_put_cmd(lun, cmd);
821 ub_end_rq(rq, scsi_status);
822 blk_start_queue(lun->disk->queue);
823 }
824
825 static void ub_end_rq(struct request *rq, unsigned int scsi_status)
826 {
827 int error;
828
829 if (scsi_status == 0) {
830 error = 0;
831 } else {
832 error = -EIO;
833 rq->errors = scsi_status;
834 }
835 __blk_end_request_all(rq, error);
836 }
837
838 static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
839 struct ub_request *urq, struct ub_scsi_cmd *cmd)
840 {
841
842 if (atomic_read(&sc->poison))
843 return -ENXIO;
844
845 ub_reset_enter(sc, urq->current_try);
846
847 if (urq->current_try >= 3)
848 return -EIO;
849 urq->current_try++;
850
851 /* Remove this if anyone complains of flooding. */
852 printk(KERN_DEBUG "%s: dir %c len/act %d/%d "
853 "[sense %x %02x %02x] retry %d\n",
854 sc->name, UB_DIR_CHAR(cmd->dir), cmd->len, cmd->act_len,
855 cmd->key, cmd->asc, cmd->ascq, urq->current_try);
856
857 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
858 ub_cmd_build_block(sc, lun, cmd, urq);
859
860 cmd->state = UB_CMDST_INIT;
861 cmd->lun = lun;
862 cmd->done = ub_rw_cmd_done;
863 cmd->back = urq;
864
865 cmd->tag = sc->tagcnt++;
866
867 #if 0 /* Wasteful */
868 return ub_submit_scsi(sc, cmd);
869 #else
870 ub_cmdq_add(sc, cmd);
871 return 0;
872 #endif
873 }
874
875 /*
876 * Submit a regular SCSI operation (not an auto-sense).
877 *
878 * The Iron Law of Good Submit Routine is:
879 * Zero return - callback is done, Nonzero return - callback is not done.
880 * No exceptions.
881 *
882 * Host is assumed locked.
883 */
884 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
885 {
886
887 if (cmd->state != UB_CMDST_INIT ||
888 (cmd->dir != UB_DIR_NONE && cmd->len == 0)) {
889 return -EINVAL;
890 }
891
892 ub_cmdq_add(sc, cmd);
893 /*
894 * We can call ub_scsi_dispatch(sc) right away here, but it's a little
895 * safer to jump to a tasklet, in case upper layers do something silly.
896 */
897 tasklet_schedule(&sc->tasklet);
898 return 0;
899 }
900
901 /*
902 * Submit the first URB for the queued command.
903 * This function does not deal with queueing in any way.
904 */
905 static int ub_scsi_cmd_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
906 {
907 struct bulk_cb_wrap *bcb;
908 int rc;
909
910 bcb = &sc->work_bcb;
911
912 /*
913 * ``If the allocation length is eighteen or greater, and a device
914 * server returns less than eithteen bytes of data, the application
915 * client should assume that the bytes not transferred would have been
916 * zeroes had the device server returned those bytes.''
917 *
918 * We zero sense for all commands so that when a packet request
919 * fails it does not return a stale sense.
920 */
921 memset(&sc->top_sense, 0, UB_SENSE_SIZE);
922
923 /* set up the command wrapper */
924 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
925 bcb->Tag = cmd->tag; /* Endianness is not important */
926 bcb->DataTransferLength = cpu_to_le32(cmd->len);
927 bcb->Flags = (cmd->dir == UB_DIR_READ) ? 0x80 : 0;
928 bcb->Lun = (cmd->lun != NULL) ? cmd->lun->num : 0;
929 bcb->Length = cmd->cdb_len;
930
931 /* copy the command payload */
932 memcpy(bcb->CDB, cmd->cdb, UB_MAX_CDB_SIZE);
933
934 UB_INIT_COMPLETION(sc->work_done);
935
936 sc->last_pipe = sc->send_bulk_pipe;
937 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->send_bulk_pipe,
938 bcb, US_BULK_CB_WRAP_LEN, ub_urb_complete, sc);
939
940 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
941 /* XXX Clear stalls */
942 ub_complete(&sc->work_done);
943 return rc;
944 }
945
946 sc->work_timer.expires = jiffies + UB_URB_TIMEOUT;
947 add_timer(&sc->work_timer);
948
949 cmd->state = UB_CMDST_CMD;
950 return 0;
951 }
952
953 /*
954 * Timeout handler.
955 */
956 static void ub_urb_timeout(unsigned long arg)
957 {
958 struct ub_dev *sc = (struct ub_dev *) arg;
959 unsigned long flags;
960
961 spin_lock_irqsave(sc->lock, flags);
962 if (!ub_is_completed(&sc->work_done))
963 usb_unlink_urb(&sc->work_urb);
964 spin_unlock_irqrestore(sc->lock, flags);
965 }
966
967 /*
968 * Completion routine for the work URB.
969 *
970 * This can be called directly from usb_submit_urb (while we have
971 * the sc->lock taken) and from an interrupt (while we do NOT have
972 * the sc->lock taken). Therefore, bounce this off to a tasklet.
973 */
974 static void ub_urb_complete(struct urb *urb)
975 {
976 struct ub_dev *sc = urb->context;
977
978 ub_complete(&sc->work_done);
979 tasklet_schedule(&sc->tasklet);
980 }
981
982 static void ub_scsi_action(unsigned long _dev)
983 {
984 struct ub_dev *sc = (struct ub_dev *) _dev;
985 unsigned long flags;
986
987 spin_lock_irqsave(sc->lock, flags);
988 ub_scsi_dispatch(sc);
989 spin_unlock_irqrestore(sc->lock, flags);
990 }
991
992 static void ub_scsi_dispatch(struct ub_dev *sc)
993 {
994 struct ub_scsi_cmd *cmd;
995 int rc;
996
997 while (!sc->reset && (cmd = ub_cmdq_peek(sc)) != NULL) {
998 if (cmd->state == UB_CMDST_DONE) {
999 ub_cmdq_pop(sc);
1000 (*cmd->done)(sc, cmd);
1001 } else if (cmd->state == UB_CMDST_INIT) {
1002 if ((rc = ub_scsi_cmd_start(sc, cmd)) == 0)
1003 break;
1004 cmd->error = rc;
1005 cmd->state = UB_CMDST_DONE;
1006 } else {
1007 if (!ub_is_completed(&sc->work_done))
1008 break;
1009 del_timer(&sc->work_timer);
1010 ub_scsi_urb_compl(sc, cmd);
1011 }
1012 }
1013 }
1014
1015 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1016 {
1017 struct urb *urb = &sc->work_urb;
1018 struct bulk_cs_wrap *bcs;
1019 int endp;
1020 int len;
1021 int rc;
1022
1023 if (atomic_read(&sc->poison)) {
1024 ub_state_done(sc, cmd, -ENODEV);
1025 return;
1026 }
1027
1028 endp = usb_pipeendpoint(sc->last_pipe);
1029 if (usb_pipein(sc->last_pipe))
1030 endp |= USB_DIR_IN;
1031
1032 if (cmd->state == UB_CMDST_CLEAR) {
1033 if (urb->status == -EPIPE) {
1034 /*
1035 * STALL while clearning STALL.
1036 * The control pipe clears itself - nothing to do.
1037 */
1038 printk(KERN_NOTICE "%s: stall on control pipe\n",
1039 sc->name);
1040 goto Bad_End;
1041 }
1042
1043 /*
1044 * We ignore the result for the halt clear.
1045 */
1046
1047 usb_reset_endpoint(sc->dev, endp);
1048
1049 ub_state_sense(sc, cmd);
1050
1051 } else if (cmd->state == UB_CMDST_CLR2STS) {
1052 if (urb->status == -EPIPE) {
1053 printk(KERN_NOTICE "%s: stall on control pipe\n",
1054 sc->name);
1055 goto Bad_End;
1056 }
1057
1058 /*
1059 * We ignore the result for the halt clear.
1060 */
1061
1062 usb_reset_endpoint(sc->dev, endp);
1063
1064 ub_state_stat(sc, cmd);
1065
1066 } else if (cmd->state == UB_CMDST_CLRRS) {
1067 if (urb->status == -EPIPE) {
1068 printk(KERN_NOTICE "%s: stall on control pipe\n",
1069 sc->name);
1070 goto Bad_End;
1071 }
1072
1073 /*
1074 * We ignore the result for the halt clear.
1075 */
1076
1077 usb_reset_endpoint(sc->dev, endp);
1078
1079 ub_state_stat_counted(sc, cmd);
1080
1081 } else if (cmd->state == UB_CMDST_CMD) {
1082 switch (urb->status) {
1083 case 0:
1084 break;
1085 case -EOVERFLOW:
1086 goto Bad_End;
1087 case -EPIPE:
1088 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1089 if (rc != 0) {
1090 printk(KERN_NOTICE "%s: "
1091 "unable to submit clear (%d)\n",
1092 sc->name, rc);
1093 /*
1094 * This is typically ENOMEM or some other such shit.
1095 * Retrying is pointless. Just do Bad End on it...
1096 */
1097 ub_state_done(sc, cmd, rc);
1098 return;
1099 }
1100 cmd->state = UB_CMDST_CLEAR;
1101 return;
1102 case -ESHUTDOWN: /* unplug */
1103 case -EILSEQ: /* unplug timeout on uhci */
1104 ub_state_done(sc, cmd, -ENODEV);
1105 return;
1106 default:
1107 goto Bad_End;
1108 }
1109 if (urb->actual_length != US_BULK_CB_WRAP_LEN) {
1110 goto Bad_End;
1111 }
1112
1113 if (cmd->dir == UB_DIR_NONE || cmd->nsg < 1) {
1114 ub_state_stat(sc, cmd);
1115 return;
1116 }
1117
1118 // udelay(125); // usb-storage has this
1119 ub_data_start(sc, cmd);
1120
1121 } else if (cmd->state == UB_CMDST_DATA) {
1122 if (urb->status == -EPIPE) {
1123 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1124 if (rc != 0) {
1125 printk(KERN_NOTICE "%s: "
1126 "unable to submit clear (%d)\n",
1127 sc->name, rc);
1128 ub_state_done(sc, cmd, rc);
1129 return;
1130 }
1131 cmd->state = UB_CMDST_CLR2STS;
1132 return;
1133 }
1134 if (urb->status == -EOVERFLOW) {
1135 /*
1136 * A babble? Failure, but we must transfer CSW now.
1137 */
1138 cmd->error = -EOVERFLOW; /* A cheap trick... */
1139 ub_state_stat(sc, cmd);
1140 return;
1141 }
1142
1143 if (cmd->dir == UB_DIR_WRITE) {
1144 /*
1145 * Do not continue writes in case of a failure.
1146 * Doing so would cause sectors to be mixed up,
1147 * which is worse than sectors lost.
1148 *
1149 * We must try to read the CSW, or many devices
1150 * get confused.
1151 */
1152 len = urb->actual_length;
1153 if (urb->status != 0 ||
1154 len != cmd->sgv[cmd->current_sg].length) {
1155 cmd->act_len += len;
1156
1157 cmd->error = -EIO;
1158 ub_state_stat(sc, cmd);
1159 return;
1160 }
1161
1162 } else {
1163 /*
1164 * If an error occurs on read, we record it, and
1165 * continue to fetch data in order to avoid bubble.
1166 *
1167 * As a small shortcut, we stop if we detect that
1168 * a CSW mixed into data.
1169 */
1170 if (urb->status != 0)
1171 cmd->error = -EIO;
1172
1173 len = urb->actual_length;
1174 if (urb->status != 0 ||
1175 len != cmd->sgv[cmd->current_sg].length) {
1176 if ((len & 0x1FF) == US_BULK_CS_WRAP_LEN)
1177 goto Bad_End;
1178 }
1179 }
1180
1181 cmd->act_len += urb->actual_length;
1182
1183 if (++cmd->current_sg < cmd->nsg) {
1184 ub_data_start(sc, cmd);
1185 return;
1186 }
1187 ub_state_stat(sc, cmd);
1188
1189 } else if (cmd->state == UB_CMDST_STAT) {
1190 if (urb->status == -EPIPE) {
1191 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1192 if (rc != 0) {
1193 printk(KERN_NOTICE "%s: "
1194 "unable to submit clear (%d)\n",
1195 sc->name, rc);
1196 ub_state_done(sc, cmd, rc);
1197 return;
1198 }
1199
1200 /*
1201 * Having a stall when getting CSW is an error, so
1202 * make sure uppper levels are not oblivious to it.
1203 */
1204 cmd->error = -EIO; /* A cheap trick... */
1205
1206 cmd->state = UB_CMDST_CLRRS;
1207 return;
1208 }
1209
1210 /* Catch everything, including -EOVERFLOW and other nasties. */
1211 if (urb->status != 0)
1212 goto Bad_End;
1213
1214 if (urb->actual_length == 0) {
1215 ub_state_stat_counted(sc, cmd);
1216 return;
1217 }
1218
1219 /*
1220 * Check the returned Bulk protocol status.
1221 * The status block has to be validated first.
1222 */
1223
1224 bcs = &sc->work_bcs;
1225
1226 if (sc->signature == cpu_to_le32(0)) {
1227 /*
1228 * This is the first reply, so do not perform the check.
1229 * Instead, remember the signature the device uses
1230 * for future checks. But do not allow a nul.
1231 */
1232 sc->signature = bcs->Signature;
1233 if (sc->signature == cpu_to_le32(0)) {
1234 ub_state_stat_counted(sc, cmd);
1235 return;
1236 }
1237 } else {
1238 if (bcs->Signature != sc->signature) {
1239 ub_state_stat_counted(sc, cmd);
1240 return;
1241 }
1242 }
1243
1244 if (bcs->Tag != cmd->tag) {
1245 /*
1246 * This usually happens when we disagree with the
1247 * device's microcode about something. For instance,
1248 * a few of them throw this after timeouts. They buffer
1249 * commands and reply at commands we timed out before.
1250 * Without flushing these replies we loop forever.
1251 */
1252 ub_state_stat_counted(sc, cmd);
1253 return;
1254 }
1255
1256 if (!sc->bad_resid) {
1257 len = le32_to_cpu(bcs->Residue);
1258 if (len != cmd->len - cmd->act_len) {
1259 /*
1260 * Only start ignoring if this cmd ended well.
1261 */
1262 if (cmd->len == cmd->act_len) {
1263 printk(KERN_NOTICE "%s: "
1264 "bad residual %d of %d, ignoring\n",
1265 sc->name, len, cmd->len);
1266 sc->bad_resid = 1;
1267 }
1268 }
1269 }
1270
1271 switch (bcs->Status) {
1272 case US_BULK_STAT_OK:
1273 break;
1274 case US_BULK_STAT_FAIL:
1275 ub_state_sense(sc, cmd);
1276 return;
1277 case US_BULK_STAT_PHASE:
1278 goto Bad_End;
1279 default:
1280 printk(KERN_INFO "%s: unknown CSW status 0x%x\n",
1281 sc->name, bcs->Status);
1282 ub_state_done(sc, cmd, -EINVAL);
1283 return;
1284 }
1285
1286 /* Not zeroing error to preserve a babble indicator */
1287 if (cmd->error != 0) {
1288 ub_state_sense(sc, cmd);
1289 return;
1290 }
1291 cmd->state = UB_CMDST_DONE;
1292 ub_cmdq_pop(sc);
1293 (*cmd->done)(sc, cmd);
1294
1295 } else if (cmd->state == UB_CMDST_SENSE) {
1296 ub_state_done(sc, cmd, -EIO);
1297
1298 } else {
1299 printk(KERN_WARNING "%s: wrong command state %d\n",
1300 sc->name, cmd->state);
1301 ub_state_done(sc, cmd, -EINVAL);
1302 return;
1303 }
1304 return;
1305
1306 Bad_End: /* Little Excel is dead */
1307 ub_state_done(sc, cmd, -EIO);
1308 }
1309
1310 /*
1311 * Factorization helper for the command state machine:
1312 * Initiate a data segment transfer.
1313 */
1314 static void ub_data_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1315 {
1316 struct scatterlist *sg = &cmd->sgv[cmd->current_sg];
1317 int pipe;
1318 int rc;
1319
1320 UB_INIT_COMPLETION(sc->work_done);
1321
1322 if (cmd->dir == UB_DIR_READ)
1323 pipe = sc->recv_bulk_pipe;
1324 else
1325 pipe = sc->send_bulk_pipe;
1326 sc->last_pipe = pipe;
1327 usb_fill_bulk_urb(&sc->work_urb, sc->dev, pipe, sg_virt(sg),
1328 sg->length, ub_urb_complete, sc);
1329
1330 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1331 /* XXX Clear stalls */
1332 ub_complete(&sc->work_done);
1333 ub_state_done(sc, cmd, rc);
1334 return;
1335 }
1336
1337 if (cmd->timeo)
1338 sc->work_timer.expires = jiffies + cmd->timeo;
1339 else
1340 sc->work_timer.expires = jiffies + UB_DATA_TIMEOUT;
1341 add_timer(&sc->work_timer);
1342
1343 cmd->state = UB_CMDST_DATA;
1344 }
1345
1346 /*
1347 * Factorization helper for the command state machine:
1348 * Finish the command.
1349 */
1350 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc)
1351 {
1352
1353 cmd->error = rc;
1354 cmd->state = UB_CMDST_DONE;
1355 ub_cmdq_pop(sc);
1356 (*cmd->done)(sc, cmd);
1357 }
1358
1359 /*
1360 * Factorization helper for the command state machine:
1361 * Submit a CSW read.
1362 */
1363 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1364 {
1365 int rc;
1366
1367 UB_INIT_COMPLETION(sc->work_done);
1368
1369 sc->last_pipe = sc->recv_bulk_pipe;
1370 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->recv_bulk_pipe,
1371 &sc->work_bcs, US_BULK_CS_WRAP_LEN, ub_urb_complete, sc);
1372
1373 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1374 /* XXX Clear stalls */
1375 ub_complete(&sc->work_done);
1376 ub_state_done(sc, cmd, rc);
1377 return -1;
1378 }
1379
1380 if (cmd->timeo)
1381 sc->work_timer.expires = jiffies + cmd->timeo;
1382 else
1383 sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;
1384 add_timer(&sc->work_timer);
1385 return 0;
1386 }
1387
1388 /*
1389 * Factorization helper for the command state machine:
1390 * Submit a CSW read and go to STAT state.
1391 */
1392 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1393 {
1394
1395 if (__ub_state_stat(sc, cmd) != 0)
1396 return;
1397
1398 cmd->stat_count = 0;
1399 cmd->state = UB_CMDST_STAT;
1400 }
1401
1402 /*
1403 * Factorization helper for the command state machine:
1404 * Submit a CSW read and go to STAT state with counter (along [C] path).
1405 */
1406 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1407 {
1408
1409 if (++cmd->stat_count >= 4) {
1410 ub_state_sense(sc, cmd);
1411 return;
1412 }
1413
1414 if (__ub_state_stat(sc, cmd) != 0)
1415 return;
1416
1417 cmd->state = UB_CMDST_STAT;
1418 }
1419
1420 /*
1421 * Factorization helper for the command state machine:
1422 * Submit a REQUEST SENSE and go to SENSE state.
1423 */
1424 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1425 {
1426 struct ub_scsi_cmd *scmd;
1427 struct scatterlist *sg;
1428 int rc;
1429
1430 if (cmd->cdb[0] == REQUEST_SENSE) {
1431 rc = -EPIPE;
1432 goto error;
1433 }
1434
1435 scmd = &sc->top_rqs_cmd;
1436 memset(scmd, 0, sizeof(struct ub_scsi_cmd));
1437 scmd->cdb[0] = REQUEST_SENSE;
1438 scmd->cdb[4] = UB_SENSE_SIZE;
1439 scmd->cdb_len = 6;
1440 scmd->dir = UB_DIR_READ;
1441 scmd->state = UB_CMDST_INIT;
1442 scmd->nsg = 1;
1443 sg = &scmd->sgv[0];
1444 sg_init_table(sg, UB_MAX_REQ_SG);
1445 sg_set_page(sg, virt_to_page(sc->top_sense), UB_SENSE_SIZE,
1446 (unsigned long)sc->top_sense & (PAGE_SIZE-1));
1447 scmd->len = UB_SENSE_SIZE;
1448 scmd->lun = cmd->lun;
1449 scmd->done = ub_top_sense_done;
1450 scmd->back = cmd;
1451
1452 scmd->tag = sc->tagcnt++;
1453
1454 cmd->state = UB_CMDST_SENSE;
1455
1456 ub_cmdq_insert(sc, scmd);
1457 return;
1458
1459 error:
1460 ub_state_done(sc, cmd, rc);
1461 }
1462
1463 /*
1464 * A helper for the command's state machine:
1465 * Submit a stall clear.
1466 */
1467 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
1468 int stalled_pipe)
1469 {
1470 int endp;
1471 struct usb_ctrlrequest *cr;
1472 int rc;
1473
1474 endp = usb_pipeendpoint(stalled_pipe);
1475 if (usb_pipein (stalled_pipe))
1476 endp |= USB_DIR_IN;
1477
1478 cr = &sc->work_cr;
1479 cr->bRequestType = USB_RECIP_ENDPOINT;
1480 cr->bRequest = USB_REQ_CLEAR_FEATURE;
1481 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
1482 cr->wIndex = cpu_to_le16(endp);
1483 cr->wLength = cpu_to_le16(0);
1484
1485 UB_INIT_COMPLETION(sc->work_done);
1486
1487 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
1488 (unsigned char*) cr, NULL, 0, ub_urb_complete, sc);
1489
1490 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1491 ub_complete(&sc->work_done);
1492 return rc;
1493 }
1494
1495 sc->work_timer.expires = jiffies + UB_CTRL_TIMEOUT;
1496 add_timer(&sc->work_timer);
1497 return 0;
1498 }
1499
1500 /*
1501 */
1502 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd)
1503 {
1504 unsigned char *sense = sc->top_sense;
1505 struct ub_scsi_cmd *cmd;
1506
1507 /*
1508 * Find the command which triggered the unit attention or a check,
1509 * save the sense into it, and advance its state machine.
1510 */
1511 if ((cmd = ub_cmdq_peek(sc)) == NULL) {
1512 printk(KERN_WARNING "%s: sense done while idle\n", sc->name);
1513 return;
1514 }
1515 if (cmd != scmd->back) {
1516 printk(KERN_WARNING "%s: "
1517 "sense done for wrong command 0x%x\n",
1518 sc->name, cmd->tag);
1519 return;
1520 }
1521 if (cmd->state != UB_CMDST_SENSE) {
1522 printk(KERN_WARNING "%s: sense done with bad cmd state %d\n",
1523 sc->name, cmd->state);
1524 return;
1525 }
1526
1527 /*
1528 * Ignoring scmd->act_len, because the buffer was pre-zeroed.
1529 */
1530 cmd->key = sense[2] & 0x0F;
1531 cmd->asc = sense[12];
1532 cmd->ascq = sense[13];
1533
1534 ub_scsi_urb_compl(sc, cmd);
1535 }
1536
1537 /*
1538 * Reset management
1539 */
1540
1541 static void ub_reset_enter(struct ub_dev *sc, int try)
1542 {
1543
1544 if (sc->reset) {
1545 /* This happens often on multi-LUN devices. */
1546 return;
1547 }
1548 sc->reset = try + 1;
1549
1550 #if 0 /* Not needed because the disconnect waits for us. */
1551 unsigned long flags;
1552 spin_lock_irqsave(&ub_lock, flags);
1553 sc->openc++;
1554 spin_unlock_irqrestore(&ub_lock, flags);
1555 #endif
1556
1557 #if 0 /* We let them stop themselves. */
1558 struct ub_lun *lun;
1559 list_for_each_entry(lun, &sc->luns, link) {
1560 blk_stop_queue(lun->disk->queue);
1561 }
1562 #endif
1563
1564 schedule_work(&sc->reset_work);
1565 }
1566
1567 static void ub_reset_task(struct work_struct *work)
1568 {
1569 struct ub_dev *sc = container_of(work, struct ub_dev, reset_work);
1570 unsigned long flags;
1571 struct ub_lun *lun;
1572 int rc;
1573
1574 if (!sc->reset) {
1575 printk(KERN_WARNING "%s: Running reset unrequested\n",
1576 sc->name);
1577 return;
1578 }
1579
1580 if (atomic_read(&sc->poison)) {
1581 ;
1582 } else if ((sc->reset & 1) == 0) {
1583 ub_sync_reset(sc);
1584 msleep(700); /* usb-storage sleeps 6s (!) */
1585 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
1586 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
1587 } else if (sc->dev->actconfig->desc.bNumInterfaces != 1) {
1588 ;
1589 } else {
1590 rc = usb_lock_device_for_reset(sc->dev, sc->intf);
1591 if (rc < 0) {
1592 printk(KERN_NOTICE
1593 "%s: usb_lock_device_for_reset failed (%d)\n",
1594 sc->name, rc);
1595 } else {
1596 rc = usb_reset_device(sc->dev);
1597 if (rc < 0) {
1598 printk(KERN_NOTICE "%s: "
1599 "usb_lock_device_for_reset failed (%d)\n",
1600 sc->name, rc);
1601 }
1602 usb_unlock_device(sc->dev);
1603 }
1604 }
1605
1606 /*
1607 * In theory, no commands can be running while reset is active,
1608 * so nobody can ask for another reset, and so we do not need any
1609 * queues of resets or anything. We do need a spinlock though,
1610 * to interact with block layer.
1611 */
1612 spin_lock_irqsave(sc->lock, flags);
1613 sc->reset = 0;
1614 tasklet_schedule(&sc->tasklet);
1615 list_for_each_entry(lun, &sc->luns, link) {
1616 blk_start_queue(lun->disk->queue);
1617 }
1618 wake_up(&sc->reset_wait);
1619 spin_unlock_irqrestore(sc->lock, flags);
1620 }
1621
1622 /*
1623 * XXX Reset brackets are too much hassle to implement, so just stub them
1624 * in order to prevent forced unbinding (which deadlocks solid when our
1625 * ->disconnect method waits for the reset to complete and this kills keventd).
1626 *
1627 * XXX Tell Alan to move usb_unlock_device inside of usb_reset_device,
1628 * or else the post_reset is invoked, and restats I/O on a locked device.
1629 */
1630 static int ub_pre_reset(struct usb_interface *iface) {
1631 return 0;
1632 }
1633
1634 static int ub_post_reset(struct usb_interface *iface) {
1635 return 0;
1636 }
1637
1638 /*
1639 * This is called from a process context.
1640 */
1641 static void ub_revalidate(struct ub_dev *sc, struct ub_lun *lun)
1642 {
1643
1644 lun->readonly = 0; /* XXX Query this from the device */
1645
1646 lun->capacity.nsec = 0;
1647 lun->capacity.bsize = 512;
1648 lun->capacity.bshift = 0;
1649
1650 if (ub_sync_tur(sc, lun) != 0)
1651 return; /* Not ready */
1652 lun->changed = 0;
1653
1654 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1655 /*
1656 * The retry here means something is wrong, either with the
1657 * device, with the transport, or with our code.
1658 * We keep this because sd.c has retries for capacity.
1659 */
1660 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1661 lun->capacity.nsec = 0;
1662 lun->capacity.bsize = 512;
1663 lun->capacity.bshift = 0;
1664 }
1665 }
1666 }
1667
1668 /*
1669 * The open funcion.
1670 * This is mostly needed to keep refcounting, but also to support
1671 * media checks on removable media drives.
1672 */
1673 static int ub_bd_open(struct block_device *bdev, fmode_t mode)
1674 {
1675 struct ub_lun *lun = bdev->bd_disk->private_data;
1676 struct ub_dev *sc = lun->udev;
1677 unsigned long flags;
1678 int rc;
1679
1680 spin_lock_irqsave(&ub_lock, flags);
1681 if (atomic_read(&sc->poison)) {
1682 spin_unlock_irqrestore(&ub_lock, flags);
1683 return -ENXIO;
1684 }
1685 sc->openc++;
1686 spin_unlock_irqrestore(&ub_lock, flags);
1687
1688 if (lun->removable || lun->readonly)
1689 check_disk_change(bdev);
1690
1691 /*
1692 * The sd.c considers ->media_present and ->changed not equivalent,
1693 * under some pretty murky conditions (a failure of READ CAPACITY).
1694 * We may need it one day.
1695 */
1696 if (lun->removable && lun->changed && !(mode & FMODE_NDELAY)) {
1697 rc = -ENOMEDIUM;
1698 goto err_open;
1699 }
1700
1701 if (lun->readonly && (mode & FMODE_WRITE)) {
1702 rc = -EROFS;
1703 goto err_open;
1704 }
1705
1706 return 0;
1707
1708 err_open:
1709 ub_put(sc);
1710 return rc;
1711 }
1712
1713 /*
1714 */
1715 static int ub_bd_release(struct gendisk *disk, fmode_t mode)
1716 {
1717 struct ub_lun *lun = disk->private_data;
1718 struct ub_dev *sc = lun->udev;
1719
1720 ub_put(sc);
1721 return 0;
1722 }
1723
1724 /*
1725 * The ioctl interface.
1726 */
1727 static int ub_bd_ioctl(struct block_device *bdev, fmode_t mode,
1728 unsigned int cmd, unsigned long arg)
1729 {
1730 struct gendisk *disk = bdev->bd_disk;
1731 void __user *usermem = (void __user *) arg;
1732
1733 return scsi_cmd_ioctl(disk->queue, disk, mode, cmd, usermem);
1734 }
1735
1736 /*
1737 * This is called by check_disk_change if we reported a media change.
1738 * The main onjective here is to discover the features of the media such as
1739 * the capacity, read-only status, etc. USB storage generally does not
1740 * need to be spun up, but if we needed it, this would be the place.
1741 *
1742 * This call can sleep.
1743 *
1744 * The return code is not used.
1745 */
1746 static int ub_bd_revalidate(struct gendisk *disk)
1747 {
1748 struct ub_lun *lun = disk->private_data;
1749
1750 ub_revalidate(lun->udev, lun);
1751
1752 /* XXX Support sector size switching like in sr.c */
1753 blk_queue_logical_block_size(disk->queue, lun->capacity.bsize);
1754 set_capacity(disk, lun->capacity.nsec);
1755 // set_disk_ro(sdkp->disk, lun->readonly);
1756
1757 return 0;
1758 }
1759
1760 /*
1761 * The check is called by the block layer to verify if the media
1762 * is still available. It is supposed to be harmless, lightweight and
1763 * non-intrusive in case the media was not changed.
1764 *
1765 * This call can sleep.
1766 *
1767 * The return code is bool!
1768 */
1769 static int ub_bd_media_changed(struct gendisk *disk)
1770 {
1771 struct ub_lun *lun = disk->private_data;
1772
1773 if (!lun->removable)
1774 return 0;
1775
1776 /*
1777 * We clean checks always after every command, so this is not
1778 * as dangerous as it looks. If the TEST_UNIT_READY fails here,
1779 * the device is actually not ready with operator or software
1780 * intervention required. One dangerous item might be a drive which
1781 * spins itself down, and come the time to write dirty pages, this
1782 * will fail, then block layer discards the data. Since we never
1783 * spin drives up, such devices simply cannot be used with ub anyway.
1784 */
1785 if (ub_sync_tur(lun->udev, lun) != 0) {
1786 lun->changed = 1;
1787 return 1;
1788 }
1789
1790 return lun->changed;
1791 }
1792
1793 static const struct block_device_operations ub_bd_fops = {
1794 .owner = THIS_MODULE,
1795 .open = ub_bd_open,
1796 .release = ub_bd_release,
1797 .locked_ioctl = ub_bd_ioctl,
1798 .media_changed = ub_bd_media_changed,
1799 .revalidate_disk = ub_bd_revalidate,
1800 };
1801
1802 /*
1803 * Common ->done routine for commands executed synchronously.
1804 */
1805 static void ub_probe_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1806 {
1807 struct completion *cop = cmd->back;
1808 complete(cop);
1809 }
1810
1811 /*
1812 * Test if the device has a check condition on it, synchronously.
1813 */
1814 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun)
1815 {
1816 struct ub_scsi_cmd *cmd;
1817 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) };
1818 unsigned long flags;
1819 struct completion compl;
1820 int rc;
1821
1822 init_completion(&compl);
1823
1824 rc = -ENOMEM;
1825 if ((cmd = kzalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1826 goto err_alloc;
1827
1828 cmd->cdb[0] = TEST_UNIT_READY;
1829 cmd->cdb_len = 6;
1830 cmd->dir = UB_DIR_NONE;
1831 cmd->state = UB_CMDST_INIT;
1832 cmd->lun = lun; /* This may be NULL, but that's ok */
1833 cmd->done = ub_probe_done;
1834 cmd->back = &compl;
1835
1836 spin_lock_irqsave(sc->lock, flags);
1837 cmd->tag = sc->tagcnt++;
1838
1839 rc = ub_submit_scsi(sc, cmd);
1840 spin_unlock_irqrestore(sc->lock, flags);
1841
1842 if (rc != 0)
1843 goto err_submit;
1844
1845 wait_for_completion(&compl);
1846
1847 rc = cmd->error;
1848
1849 if (rc == -EIO && cmd->key != 0) /* Retries for benh's key */
1850 rc = cmd->key;
1851
1852 err_submit:
1853 kfree(cmd);
1854 err_alloc:
1855 return rc;
1856 }
1857
1858 /*
1859 * Read the SCSI capacity synchronously (for probing).
1860 */
1861 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
1862 struct ub_capacity *ret)
1863 {
1864 struct ub_scsi_cmd *cmd;
1865 struct scatterlist *sg;
1866 char *p;
1867 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) + 8 };
1868 unsigned long flags;
1869 unsigned int bsize, shift;
1870 unsigned long nsec;
1871 struct completion compl;
1872 int rc;
1873
1874 init_completion(&compl);
1875
1876 rc = -ENOMEM;
1877 if ((cmd = kzalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1878 goto err_alloc;
1879 p = (char *)cmd + sizeof(struct ub_scsi_cmd);
1880
1881 cmd->cdb[0] = 0x25;
1882 cmd->cdb_len = 10;
1883 cmd->dir = UB_DIR_READ;
1884 cmd->state = UB_CMDST_INIT;
1885 cmd->nsg = 1;
1886 sg = &cmd->sgv[0];
1887 sg_init_table(sg, UB_MAX_REQ_SG);
1888 sg_set_page(sg, virt_to_page(p), 8, (unsigned long)p & (PAGE_SIZE-1));
1889 cmd->len = 8;
1890 cmd->lun = lun;
1891 cmd->done = ub_probe_done;
1892 cmd->back = &compl;
1893
1894 spin_lock_irqsave(sc->lock, flags);
1895 cmd->tag = sc->tagcnt++;
1896
1897 rc = ub_submit_scsi(sc, cmd);
1898 spin_unlock_irqrestore(sc->lock, flags);
1899
1900 if (rc != 0)
1901 goto err_submit;
1902
1903 wait_for_completion(&compl);
1904
1905 if (cmd->error != 0) {
1906 rc = -EIO;
1907 goto err_read;
1908 }
1909 if (cmd->act_len != 8) {
1910 rc = -EIO;
1911 goto err_read;
1912 }
1913
1914 /* sd.c special-cases sector size of 0 to mean 512. Needed? Safe? */
1915 nsec = be32_to_cpu(*(__be32 *)p) + 1;
1916 bsize = be32_to_cpu(*(__be32 *)(p + 4));
1917 switch (bsize) {
1918 case 512: shift = 0; break;
1919 case 1024: shift = 1; break;
1920 case 2048: shift = 2; break;
1921 case 4096: shift = 3; break;
1922 default:
1923 rc = -EDOM;
1924 goto err_inv_bsize;
1925 }
1926
1927 ret->bsize = bsize;
1928 ret->bshift = shift;
1929 ret->nsec = nsec << shift;
1930 rc = 0;
1931
1932 err_inv_bsize:
1933 err_read:
1934 err_submit:
1935 kfree(cmd);
1936 err_alloc:
1937 return rc;
1938 }
1939
1940 /*
1941 */
1942 static void ub_probe_urb_complete(struct urb *urb)
1943 {
1944 struct completion *cop = urb->context;
1945 complete(cop);
1946 }
1947
1948 static void ub_probe_timeout(unsigned long arg)
1949 {
1950 struct completion *cop = (struct completion *) arg;
1951 complete(cop);
1952 }
1953
1954 /*
1955 * Reset with a Bulk reset.
1956 */
1957 static int ub_sync_reset(struct ub_dev *sc)
1958 {
1959 int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
1960 struct usb_ctrlrequest *cr;
1961 struct completion compl;
1962 struct timer_list timer;
1963 int rc;
1964
1965 init_completion(&compl);
1966
1967 cr = &sc->work_cr;
1968 cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
1969 cr->bRequest = US_BULK_RESET_REQUEST;
1970 cr->wValue = cpu_to_le16(0);
1971 cr->wIndex = cpu_to_le16(ifnum);
1972 cr->wLength = cpu_to_le16(0);
1973
1974 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
1975 (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
1976
1977 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
1978 printk(KERN_WARNING
1979 "%s: Unable to submit a bulk reset (%d)\n", sc->name, rc);
1980 return rc;
1981 }
1982
1983 init_timer(&timer);
1984 timer.function = ub_probe_timeout;
1985 timer.data = (unsigned long) &compl;
1986 timer.expires = jiffies + UB_CTRL_TIMEOUT;
1987 add_timer(&timer);
1988
1989 wait_for_completion(&compl);
1990
1991 del_timer_sync(&timer);
1992 usb_kill_urb(&sc->work_urb);
1993
1994 return sc->work_urb.status;
1995 }
1996
1997 /*
1998 * Get number of LUNs by the way of Bulk GetMaxLUN command.
1999 */
2000 static int ub_sync_getmaxlun(struct ub_dev *sc)
2001 {
2002 int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
2003 unsigned char *p;
2004 enum { ALLOC_SIZE = 1 };
2005 struct usb_ctrlrequest *cr;
2006 struct completion compl;
2007 struct timer_list timer;
2008 int nluns;
2009 int rc;
2010
2011 init_completion(&compl);
2012
2013 rc = -ENOMEM;
2014 if ((p = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
2015 goto err_alloc;
2016 *p = 55;
2017
2018 cr = &sc->work_cr;
2019 cr->bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE;
2020 cr->bRequest = US_BULK_GET_MAX_LUN;
2021 cr->wValue = cpu_to_le16(0);
2022 cr->wIndex = cpu_to_le16(ifnum);
2023 cr->wLength = cpu_to_le16(1);
2024
2025 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->recv_ctrl_pipe,
2026 (unsigned char*) cr, p, 1, ub_probe_urb_complete, &compl);
2027
2028 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0)
2029 goto err_submit;
2030
2031 init_timer(&timer);
2032 timer.function = ub_probe_timeout;
2033 timer.data = (unsigned long) &compl;
2034 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2035 add_timer(&timer);
2036
2037 wait_for_completion(&compl);
2038
2039 del_timer_sync(&timer);
2040 usb_kill_urb(&sc->work_urb);
2041
2042 if ((rc = sc->work_urb.status) < 0)
2043 goto err_io;
2044
2045 if (sc->work_urb.actual_length != 1) {
2046 nluns = 0;
2047 } else {
2048 if ((nluns = *p) == 55) {
2049 nluns = 0;
2050 } else {
2051 /* GetMaxLUN returns the maximum LUN number */
2052 nluns += 1;
2053 if (nluns > UB_MAX_LUNS)
2054 nluns = UB_MAX_LUNS;
2055 }
2056 }
2057
2058 kfree(p);
2059 return nluns;
2060
2061 err_io:
2062 err_submit:
2063 kfree(p);
2064 err_alloc:
2065 return rc;
2066 }
2067
2068 /*
2069 * Clear initial stalls.
2070 */
2071 static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe)
2072 {
2073 int endp;
2074 struct usb_ctrlrequest *cr;
2075 struct completion compl;
2076 struct timer_list timer;
2077 int rc;
2078
2079 init_completion(&compl);
2080
2081 endp = usb_pipeendpoint(stalled_pipe);
2082 if (usb_pipein (stalled_pipe))
2083 endp |= USB_DIR_IN;
2084
2085 cr = &sc->work_cr;
2086 cr->bRequestType = USB_RECIP_ENDPOINT;
2087 cr->bRequest = USB_REQ_CLEAR_FEATURE;
2088 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
2089 cr->wIndex = cpu_to_le16(endp);
2090 cr->wLength = cpu_to_le16(0);
2091
2092 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
2093 (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
2094
2095 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
2096 printk(KERN_WARNING
2097 "%s: Unable to submit a probe clear (%d)\n", sc->name, rc);
2098 return rc;
2099 }
2100
2101 init_timer(&timer);
2102 timer.function = ub_probe_timeout;
2103 timer.data = (unsigned long) &compl;
2104 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2105 add_timer(&timer);
2106
2107 wait_for_completion(&compl);
2108
2109 del_timer_sync(&timer);
2110 usb_kill_urb(&sc->work_urb);
2111
2112 usb_reset_endpoint(sc->dev, endp);
2113
2114 return 0;
2115 }
2116
2117 /*
2118 * Get the pipe settings.
2119 */
2120 static int ub_get_pipes(struct ub_dev *sc, struct usb_device *dev,
2121 struct usb_interface *intf)
2122 {
2123 struct usb_host_interface *altsetting = intf->cur_altsetting;
2124 struct usb_endpoint_descriptor *ep_in = NULL;
2125 struct usb_endpoint_descriptor *ep_out = NULL;
2126 struct usb_endpoint_descriptor *ep;
2127 int i;
2128
2129 /*
2130 * Find the endpoints we need.
2131 * We are expecting a minimum of 2 endpoints - in and out (bulk).
2132 * We will ignore any others.
2133 */
2134 for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
2135 ep = &altsetting->endpoint[i].desc;
2136
2137 /* Is it a BULK endpoint? */
2138 if (usb_endpoint_xfer_bulk(ep)) {
2139 /* BULK in or out? */
2140 if (usb_endpoint_dir_in(ep)) {
2141 if (ep_in == NULL)
2142 ep_in = ep;
2143 } else {
2144 if (ep_out == NULL)
2145 ep_out = ep;
2146 }
2147 }
2148 }
2149
2150 if (ep_in == NULL || ep_out == NULL) {
2151 printk(KERN_NOTICE "%s: failed endpoint check\n", sc->name);
2152 return -ENODEV;
2153 }
2154
2155 /* Calculate and store the pipe values */
2156 sc->send_ctrl_pipe = usb_sndctrlpipe(dev, 0);
2157 sc->recv_ctrl_pipe = usb_rcvctrlpipe(dev, 0);
2158 sc->send_bulk_pipe = usb_sndbulkpipe(dev,
2159 usb_endpoint_num(ep_out));
2160 sc->recv_bulk_pipe = usb_rcvbulkpipe(dev,
2161 usb_endpoint_num(ep_in));
2162
2163 return 0;
2164 }
2165
2166 /*
2167 * Probing is done in the process context, which allows us to cheat
2168 * and not to build a state machine for the discovery.
2169 */
2170 static int ub_probe(struct usb_interface *intf,
2171 const struct usb_device_id *dev_id)
2172 {
2173 struct ub_dev *sc;
2174 int nluns;
2175 int rc;
2176 int i;
2177
2178 if (usb_usual_check_type(dev_id, USB_US_TYPE_UB))
2179 return -ENXIO;
2180
2181 rc = -ENOMEM;
2182 if ((sc = kzalloc(sizeof(struct ub_dev), GFP_KERNEL)) == NULL)
2183 goto err_core;
2184 sc->lock = ub_next_lock();
2185 INIT_LIST_HEAD(&sc->luns);
2186 usb_init_urb(&sc->work_urb);
2187 tasklet_init(&sc->tasklet, ub_scsi_action, (unsigned long)sc);
2188 atomic_set(&sc->poison, 0);
2189 INIT_WORK(&sc->reset_work, ub_reset_task);
2190 init_waitqueue_head(&sc->reset_wait);
2191
2192 init_timer(&sc->work_timer);
2193 sc->work_timer.data = (unsigned long) sc;
2194 sc->work_timer.function = ub_urb_timeout;
2195
2196 ub_init_completion(&sc->work_done);
2197 sc->work_done.done = 1; /* A little yuk, but oh well... */
2198
2199 sc->dev = interface_to_usbdev(intf);
2200 sc->intf = intf;
2201 // sc->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2202 usb_set_intfdata(intf, sc);
2203 usb_get_dev(sc->dev);
2204 /*
2205 * Since we give the interface struct to the block level through
2206 * disk->driverfs_dev, we have to pin it. Otherwise, block_uevent
2207 * oopses on close after a disconnect (kernels 2.6.16 and up).
2208 */
2209 usb_get_intf(sc->intf);
2210
2211 snprintf(sc->name, 12, DRV_NAME "(%d.%d)",
2212 sc->dev->bus->busnum, sc->dev->devnum);
2213
2214 /* XXX Verify that we can handle the device (from descriptors) */
2215
2216 if (ub_get_pipes(sc, sc->dev, intf) != 0)
2217 goto err_dev_desc;
2218
2219 /*
2220 * At this point, all USB initialization is done, do upper layer.
2221 * We really hate halfway initialized structures, so from the
2222 * invariants perspective, this ub_dev is fully constructed at
2223 * this point.
2224 */
2225
2226 /*
2227 * This is needed to clear toggles. It is a problem only if we do
2228 * `rmmod ub && modprobe ub` without disconnects, but we like that.
2229 */
2230 #if 0 /* iPod Mini fails if we do this (big white iPod works) */
2231 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
2232 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
2233 #endif
2234
2235 /*
2236 * The way this is used by the startup code is a little specific.
2237 * A SCSI check causes a USB stall. Our common case code sees it
2238 * and clears the check, after which the device is ready for use.
2239 * But if a check was not present, any command other than
2240 * TEST_UNIT_READY ends with a lockup (including REQUEST_SENSE).
2241 *
2242 * If we neglect to clear the SCSI check, the first real command fails
2243 * (which is the capacity readout). We clear that and retry, but why
2244 * causing spurious retries for no reason.
2245 *
2246 * Revalidation may start with its own TEST_UNIT_READY, but that one
2247 * has to succeed, so we clear checks with an additional one here.
2248 * In any case it's not our business how revaliadation is implemented.
2249 */
2250 for (i = 0; i < 3; i++) { /* Retries for the schwag key from KS'04 */
2251 if ((rc = ub_sync_tur(sc, NULL)) <= 0) break;
2252 if (rc != 0x6) break;
2253 msleep(10);
2254 }
2255
2256 nluns = 1;
2257 for (i = 0; i < 3; i++) {
2258 if ((rc = ub_sync_getmaxlun(sc)) < 0)
2259 break;
2260 if (rc != 0) {
2261 nluns = rc;
2262 break;
2263 }
2264 msleep(100);
2265 }
2266
2267 for (i = 0; i < nluns; i++) {
2268 ub_probe_lun(sc, i);
2269 }
2270 return 0;
2271
2272 err_dev_desc:
2273 usb_set_intfdata(intf, NULL);
2274 usb_put_intf(sc->intf);
2275 usb_put_dev(sc->dev);
2276 kfree(sc);
2277 err_core:
2278 return rc;
2279 }
2280
2281 static int ub_probe_lun(struct ub_dev *sc, int lnum)
2282 {
2283 struct ub_lun *lun;
2284 struct request_queue *q;
2285 struct gendisk *disk;
2286 int rc;
2287
2288 rc = -ENOMEM;
2289 if ((lun = kzalloc(sizeof(struct ub_lun), GFP_KERNEL)) == NULL)
2290 goto err_alloc;
2291 lun->num = lnum;
2292
2293 rc = -ENOSR;
2294 if ((lun->id = ub_id_get()) == -1)
2295 goto err_id;
2296
2297 lun->udev = sc;
2298
2299 snprintf(lun->name, 16, DRV_NAME "%c(%d.%d.%d)",
2300 lun->id + 'a', sc->dev->bus->busnum, sc->dev->devnum, lun->num);
2301
2302 lun->removable = 1; /* XXX Query this from the device */
2303 lun->changed = 1; /* ub_revalidate clears only */
2304 ub_revalidate(sc, lun);
2305
2306 rc = -ENOMEM;
2307 if ((disk = alloc_disk(UB_PARTS_PER_LUN)) == NULL)
2308 goto err_diskalloc;
2309
2310 sprintf(disk->disk_name, DRV_NAME "%c", lun->id + 'a');
2311 disk->major = UB_MAJOR;
2312 disk->first_minor = lun->id * UB_PARTS_PER_LUN;
2313 disk->fops = &ub_bd_fops;
2314 disk->private_data = lun;
2315 disk->driverfs_dev = &sc->intf->dev;
2316
2317 rc = -ENOMEM;
2318 if ((q = blk_init_queue(ub_request_fn, sc->lock)) == NULL)
2319 goto err_blkqinit;
2320
2321 disk->queue = q;
2322
2323 blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
2324 blk_queue_max_segments(q, UB_MAX_REQ_SG);
2325 blk_queue_segment_boundary(q, 0xffffffff); /* Dubious. */
2326 blk_queue_max_hw_sectors(q, UB_MAX_SECTORS);
2327 blk_queue_logical_block_size(q, lun->capacity.bsize);
2328
2329 lun->disk = disk;
2330 q->queuedata = lun;
2331 list_add(&lun->link, &sc->luns);
2332
2333 set_capacity(disk, lun->capacity.nsec);
2334 if (lun->removable)
2335 disk->flags |= GENHD_FL_REMOVABLE;
2336
2337 add_disk(disk);
2338
2339 return 0;
2340
2341 err_blkqinit:
2342 put_disk(disk);
2343 err_diskalloc:
2344 ub_id_put(lun->id);
2345 err_id:
2346 kfree(lun);
2347 err_alloc:
2348 return rc;
2349 }
2350
2351 static void ub_disconnect(struct usb_interface *intf)
2352 {
2353 struct ub_dev *sc = usb_get_intfdata(intf);
2354 struct ub_lun *lun;
2355 unsigned long flags;
2356
2357 /*
2358 * Prevent ub_bd_release from pulling the rug from under us.
2359 * XXX This is starting to look like a kref.
2360 * XXX Why not to take this ref at probe time?
2361 */
2362 spin_lock_irqsave(&ub_lock, flags);
2363 sc->openc++;
2364 spin_unlock_irqrestore(&ub_lock, flags);
2365
2366 /*
2367 * Fence stall clearings, operations triggered by unlinkings and so on.
2368 * We do not attempt to unlink any URBs, because we do not trust the
2369 * unlink paths in HC drivers. Also, we get -84 upon disconnect anyway.
2370 */
2371 atomic_set(&sc->poison, 1);
2372
2373 /*
2374 * Wait for reset to end, if any.
2375 */
2376 wait_event(sc->reset_wait, !sc->reset);
2377
2378 /*
2379 * Blow away queued commands.
2380 *
2381 * Actually, this never works, because before we get here
2382 * the HCD terminates outstanding URB(s). It causes our
2383 * SCSI command queue to advance, commands fail to submit,
2384 * and the whole queue drains. So, we just use this code to
2385 * print warnings.
2386 */
2387 spin_lock_irqsave(sc->lock, flags);
2388 {
2389 struct ub_scsi_cmd *cmd;
2390 int cnt = 0;
2391 while ((cmd = ub_cmdq_peek(sc)) != NULL) {
2392 cmd->error = -ENOTCONN;
2393 cmd->state = UB_CMDST_DONE;
2394 ub_cmdq_pop(sc);
2395 (*cmd->done)(sc, cmd);
2396 cnt++;
2397 }
2398 if (cnt != 0) {
2399 printk(KERN_WARNING "%s: "
2400 "%d was queued after shutdown\n", sc->name, cnt);
2401 }
2402 }
2403 spin_unlock_irqrestore(sc->lock, flags);
2404
2405 /*
2406 * Unregister the upper layer.
2407 */
2408 list_for_each_entry(lun, &sc->luns, link) {
2409 del_gendisk(lun->disk);
2410 /*
2411 * I wish I could do:
2412 * queue_flag_set(QUEUE_FLAG_DEAD, q);
2413 * As it is, we rely on our internal poisoning and let
2414 * the upper levels to spin furiously failing all the I/O.
2415 */
2416 }
2417
2418 /*
2419 * Testing for -EINPROGRESS is always a bug, so we are bending
2420 * the rules a little.
2421 */
2422 spin_lock_irqsave(sc->lock, flags);
2423 if (sc->work_urb.status == -EINPROGRESS) { /* janitors: ignore */
2424 printk(KERN_WARNING "%s: "
2425 "URB is active after disconnect\n", sc->name);
2426 }
2427 spin_unlock_irqrestore(sc->lock, flags);
2428
2429 /*
2430 * There is virtually no chance that other CPU runs a timeout so long
2431 * after ub_urb_complete should have called del_timer, but only if HCD
2432 * didn't forget to deliver a callback on unlink.
2433 */
2434 del_timer_sync(&sc->work_timer);
2435
2436 /*
2437 * At this point there must be no commands coming from anyone
2438 * and no URBs left in transit.
2439 */
2440
2441 ub_put(sc);
2442 }
2443
2444 static struct usb_driver ub_driver = {
2445 .name = "ub",
2446 .probe = ub_probe,
2447 .disconnect = ub_disconnect,
2448 .id_table = ub_usb_ids,
2449 .pre_reset = ub_pre_reset,
2450 .post_reset = ub_post_reset,
2451 };
2452
2453 static int __init ub_init(void)
2454 {
2455 int rc;
2456 int i;
2457
2458 for (i = 0; i < UB_QLOCK_NUM; i++)
2459 spin_lock_init(&ub_qlockv[i]);
2460
2461 if ((rc = register_blkdev(UB_MAJOR, DRV_NAME)) != 0)
2462 goto err_regblkdev;
2463
2464 if ((rc = usb_register(&ub_driver)) != 0)
2465 goto err_register;
2466
2467 usb_usual_set_present(USB_US_TYPE_UB);
2468 return 0;
2469
2470 err_register:
2471 unregister_blkdev(UB_MAJOR, DRV_NAME);
2472 err_regblkdev:
2473 return rc;
2474 }
2475
2476 static void __exit ub_exit(void)
2477 {
2478 usb_deregister(&ub_driver);
2479
2480 unregister_blkdev(UB_MAJOR, DRV_NAME);
2481 usb_usual_clear_present(USB_US_TYPE_UB);
2482 }
2483
2484 module_init(ub_init);
2485 module_exit(ub_exit);
2486
2487 MODULE_LICENSE("GPL");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree