Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[linux/fpc-iii.git] / drivers / usb / storage / scsiglue.c
blob18509e6c21ab84e7d3133f7a0e428ba462d2a24b
1 /* Driver for USB Mass Storage compliant devices
2 * SCSI layer glue code
4 * Current development and maintenance by:
5 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
7 * Developed with the assistance of:
8 * (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
9 * (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
11 * Initial work by:
12 * (c) 1999 Michael Gee (michael@linuxspecific.com)
14 * This driver is based on the 'USB Mass Storage Class' document. This
15 * describes in detail the protocol used to communicate with such
16 * devices. Clearly, the designers had SCSI and ATAPI commands in
17 * mind when they created this document. The commands are all very
18 * similar to commands in the SCSI-II and ATAPI specifications.
20 * It is important to note that in a number of cases this class
21 * exhibits class-specific exemptions from the USB specification.
22 * Notably the usage of NAK, STALL and ACK differs from the norm, in
23 * that they are used to communicate wait, failed and OK on commands.
25 * Also, for certain devices, the interrupt endpoint is used to convey
26 * status of a command.
28 * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
29 * information about this driver.
31 * This program is free software; you can redistribute it and/or modify it
32 * under the terms of the GNU General Public License as published by the
33 * Free Software Foundation; either version 2, or (at your option) any
34 * later version.
36 * This program is distributed in the hope that it will be useful, but
37 * WITHOUT ANY WARRANTY; without even the implied warranty of
38 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
39 * General Public License for more details.
41 * You should have received a copy of the GNU General Public License along
42 * with this program; if not, write to the Free Software Foundation, Inc.,
43 * 675 Mass Ave, Cambridge, MA 02139, USA.
46 #include <linux/module.h>
47 #include <linux/mutex.h>
49 #include <scsi/scsi.h>
50 #include <scsi/scsi_cmnd.h>
51 #include <scsi/scsi_devinfo.h>
52 #include <scsi/scsi_device.h>
53 #include <scsi/scsi_eh.h>
55 #include "usb.h"
56 #include "scsiglue.h"
57 #include "debug.h"
58 #include "transport.h"
59 #include "protocol.h"
61 /* Vendor IDs for companies that seem to include the READ CAPACITY bug
62 * in all their devices
64 #define VENDOR_ID_NOKIA 0x0421
65 #define VENDOR_ID_NIKON 0x04b0
66 #define VENDOR_ID_PENTAX 0x0a17
67 #define VENDOR_ID_MOTOROLA 0x22b8
69 /***********************************************************************
70 * Host functions
71 ***********************************************************************/
73 static const char* host_info(struct Scsi_Host *host)
75 struct us_data *us = host_to_us(host);
76 return us->scsi_name;
79 static int slave_alloc (struct scsi_device *sdev)
82 * Set the INQUIRY transfer length to 36. We don't use any of
83 * the extra data and many devices choke if asked for more or
84 * less than 36 bytes.
86 sdev->inquiry_len = 36;
88 /* USB has unusual DMA-alignment requirements: Although the
89 * starting address of each scatter-gather element doesn't matter,
90 * the length of each element except the last must be divisible
91 * by the Bulk maxpacket value. There's currently no way to
92 * express this by block-layer constraints, so we'll cop out
93 * and simply require addresses to be aligned at 512-byte
94 * boundaries. This is okay since most block I/O involves
95 * hardware sectors that are multiples of 512 bytes in length,
96 * and since host controllers up through USB 2.0 have maxpacket
97 * values no larger than 512.
99 * But it doesn't suffice for Wireless USB, where Bulk maxpacket
100 * values can be as large as 2048. To make that work properly
101 * will require changes to the block layer.
103 blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
105 return 0;
108 static int slave_configure(struct scsi_device *sdev)
110 struct us_data *us = host_to_us(sdev->host);
112 /* Many devices have trouble transferring more than 32KB at a time,
113 * while others have trouble with more than 64K. At this time we
114 * are limiting both to 32K (64 sectores).
116 if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
117 unsigned int max_sectors = 64;
119 if (us->fflags & US_FL_MAX_SECTORS_MIN)
120 max_sectors = PAGE_CACHE_SIZE >> 9;
121 if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
122 blk_queue_max_hw_sectors(sdev->request_queue,
123 max_sectors);
124 } else if (sdev->type == TYPE_TAPE) {
125 /* Tapes need much higher max_sector limits, so just
126 * raise it to the maximum possible (4 GB / 512) and
127 * let the queue segment size sort out the real limit.
129 blk_queue_max_hw_sectors(sdev->request_queue, 0x7FFFFF);
132 /* Some USB host controllers can't do DMA; they have to use PIO.
133 * They indicate this by setting their dma_mask to NULL. For
134 * such controllers we need to make sure the block layer sets
135 * up bounce buffers in addressable memory.
137 if (!us->pusb_dev->bus->controller->dma_mask)
138 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
140 /* We can't put these settings in slave_alloc() because that gets
141 * called before the device type is known. Consequently these
142 * settings can't be overridden via the scsi devinfo mechanism. */
143 if (sdev->type == TYPE_DISK) {
145 /* Some vendors seem to put the READ CAPACITY bug into
146 * all their devices -- primarily makers of cell phones
147 * and digital cameras. Since these devices always use
148 * flash media and can be expected to have an even number
149 * of sectors, we will always enable the CAPACITY_HEURISTICS
150 * flag unless told otherwise. */
151 switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
152 case VENDOR_ID_NOKIA:
153 case VENDOR_ID_NIKON:
154 case VENDOR_ID_PENTAX:
155 case VENDOR_ID_MOTOROLA:
156 if (!(us->fflags & (US_FL_FIX_CAPACITY |
157 US_FL_CAPACITY_OK)))
158 us->fflags |= US_FL_CAPACITY_HEURISTICS;
159 break;
162 /* Disk-type devices use MODE SENSE(6) if the protocol
163 * (SubClass) is Transparent SCSI, otherwise they use
164 * MODE SENSE(10). */
165 if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
166 sdev->use_10_for_ms = 1;
168 /* Many disks only accept MODE SENSE transfer lengths of
169 * 192 bytes (that's what Windows uses). */
170 sdev->use_192_bytes_for_3f = 1;
172 /* Some devices don't like MODE SENSE with page=0x3f,
173 * which is the command used for checking if a device
174 * is write-protected. Now that we tell the sd driver
175 * to do a 192-byte transfer with this command the
176 * majority of devices work fine, but a few still can't
177 * handle it. The sd driver will simply assume those
178 * devices are write-enabled. */
179 if (us->fflags & US_FL_NO_WP_DETECT)
180 sdev->skip_ms_page_3f = 1;
182 /* A number of devices have problems with MODE SENSE for
183 * page x08, so we will skip it. */
184 sdev->skip_ms_page_8 = 1;
186 /* Some devices don't handle VPD pages correctly */
187 sdev->skip_vpd_pages = 1;
189 /* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
190 sdev->no_report_opcodes = 1;
192 /* Do not attempt to use WRITE SAME */
193 sdev->no_write_same = 1;
195 /* Some disks return the total number of blocks in response
196 * to READ CAPACITY rather than the highest block number.
197 * If this device makes that mistake, tell the sd driver. */
198 if (us->fflags & US_FL_FIX_CAPACITY)
199 sdev->fix_capacity = 1;
201 /* A few disks have two indistinguishable version, one of
202 * which reports the correct capacity and the other does not.
203 * The sd driver has to guess which is the case. */
204 if (us->fflags & US_FL_CAPACITY_HEURISTICS)
205 sdev->guess_capacity = 1;
207 /* Some devices cannot handle READ_CAPACITY_16 */
208 if (us->fflags & US_FL_NO_READ_CAPACITY_16)
209 sdev->no_read_capacity_16 = 1;
212 * Many devices do not respond properly to READ_CAPACITY_16.
213 * Tell the SCSI layer to try READ_CAPACITY_10 first.
214 * However some USB 3.0 drive enclosures return capacity
215 * modulo 2TB. Those must use READ_CAPACITY_16
217 if (!(us->fflags & US_FL_NEEDS_CAP16))
218 sdev->try_rc_10_first = 1;
220 /* assume SPC3 or latter devices support sense size > 18 */
221 if (sdev->scsi_level > SCSI_SPC_2)
222 us->fflags |= US_FL_SANE_SENSE;
224 /* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
225 * Hardware Error) when any low-level error occurs,
226 * recoverable or not. Setting this flag tells the SCSI
227 * midlayer to retry such commands, which frequently will
228 * succeed and fix the error. The worst this can lead to
229 * is an occasional series of retries that will all fail. */
230 sdev->retry_hwerror = 1;
232 /* USB disks should allow restart. Some drives spin down
233 * automatically, requiring a START-STOP UNIT command. */
234 sdev->allow_restart = 1;
236 /* Some USB cardreaders have trouble reading an sdcard's last
237 * sector in a larger then 1 sector read, since the performance
238 * impact is negible we set this flag for all USB disks */
239 sdev->last_sector_bug = 1;
241 /* Enable last-sector hacks for single-target devices using
242 * the Bulk-only transport, unless we already know the
243 * capacity will be decremented or is correct. */
244 if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
245 US_FL_SCM_MULT_TARG)) &&
246 us->protocol == USB_PR_BULK)
247 us->use_last_sector_hacks = 1;
249 /* Check if write cache default on flag is set or not */
250 if (us->fflags & US_FL_WRITE_CACHE)
251 sdev->wce_default_on = 1;
253 } else {
255 /* Non-disk-type devices don't need to blacklist any pages
256 * or to force 192-byte transfer lengths for MODE SENSE.
257 * But they do need to use MODE SENSE(10). */
258 sdev->use_10_for_ms = 1;
260 /* Some (fake) usb cdrom devices don't like READ_DISC_INFO */
261 if (us->fflags & US_FL_NO_READ_DISC_INFO)
262 sdev->no_read_disc_info = 1;
265 /* The CB and CBI transports have no way to pass LUN values
266 * other than the bits in the second byte of a CDB. But those
267 * bits don't get set to the LUN value if the device reports
268 * scsi_level == 0 (UNKNOWN). Hence such devices must necessarily
269 * be single-LUN.
271 if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
272 sdev->scsi_level == SCSI_UNKNOWN)
273 us->max_lun = 0;
275 /* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
276 * REMOVAL command, so suppress those commands. */
277 if (us->fflags & US_FL_NOT_LOCKABLE)
278 sdev->lockable = 0;
280 /* this is to satisfy the compiler, tho I don't think the
281 * return code is ever checked anywhere. */
282 return 0;
285 static int target_alloc(struct scsi_target *starget)
287 struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
290 * Some USB drives don't support REPORT LUNS, even though they
291 * report a SCSI revision level above 2. Tell the SCSI layer
292 * not to issue that command; it will perform a normal sequential
293 * scan instead.
295 starget->no_report_luns = 1;
298 * The UFI spec treats the Peripheral Qualifier bits in an
299 * INQUIRY result as reserved and requires devices to set them
300 * to 0. However the SCSI spec requires these bits to be set
301 * to 3 to indicate when a LUN is not present.
303 * Let the scanning code know if this target merely sets
304 * Peripheral Device Type to 0x1f to indicate no LUN.
306 if (us->subclass == USB_SC_UFI)
307 starget->pdt_1f_for_no_lun = 1;
309 return 0;
312 /* queue a command */
313 /* This is always called with scsi_lock(host) held */
314 static int queuecommand_lck(struct scsi_cmnd *srb,
315 void (*done)(struct scsi_cmnd *))
317 struct us_data *us = host_to_us(srb->device->host);
319 /* check for state-transition errors */
320 if (us->srb != NULL) {
321 printk(KERN_ERR USB_STORAGE "Error in %s: us->srb = %p\n",
322 __func__, us->srb);
323 return SCSI_MLQUEUE_HOST_BUSY;
326 /* fail the command if we are disconnecting */
327 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
328 usb_stor_dbg(us, "Fail command during disconnect\n");
329 srb->result = DID_NO_CONNECT << 16;
330 done(srb);
331 return 0;
334 /* enqueue the command and wake up the control thread */
335 srb->scsi_done = done;
336 us->srb = srb;
337 complete(&us->cmnd_ready);
339 return 0;
342 static DEF_SCSI_QCMD(queuecommand)
344 /***********************************************************************
345 * Error handling functions
346 ***********************************************************************/
348 /* Command timeout and abort */
349 static int command_abort(struct scsi_cmnd *srb)
351 struct us_data *us = host_to_us(srb->device->host);
353 usb_stor_dbg(us, "%s called\n", __func__);
355 /* us->srb together with the TIMED_OUT, RESETTING, and ABORTING
356 * bits are protected by the host lock. */
357 scsi_lock(us_to_host(us));
359 /* Is this command still active? */
360 if (us->srb != srb) {
361 scsi_unlock(us_to_host(us));
362 usb_stor_dbg(us, "-- nothing to abort\n");
363 return FAILED;
366 /* Set the TIMED_OUT bit. Also set the ABORTING bit, but only if
367 * a device reset isn't already in progress (to avoid interfering
368 * with the reset). Note that we must retain the host lock while
369 * calling usb_stor_stop_transport(); otherwise it might interfere
370 * with an auto-reset that begins as soon as we release the lock. */
371 set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
372 if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
373 set_bit(US_FLIDX_ABORTING, &us->dflags);
374 usb_stor_stop_transport(us);
376 scsi_unlock(us_to_host(us));
378 /* Wait for the aborted command to finish */
379 wait_for_completion(&us->notify);
380 return SUCCESS;
383 /* This invokes the transport reset mechanism to reset the state of the
384 * device */
385 static int device_reset(struct scsi_cmnd *srb)
387 struct us_data *us = host_to_us(srb->device->host);
388 int result;
390 usb_stor_dbg(us, "%s called\n", __func__);
392 /* lock the device pointers and do the reset */
393 mutex_lock(&(us->dev_mutex));
394 result = us->transport_reset(us);
395 mutex_unlock(&us->dev_mutex);
397 return result < 0 ? FAILED : SUCCESS;
400 /* Simulate a SCSI bus reset by resetting the device's USB port. */
401 static int bus_reset(struct scsi_cmnd *srb)
403 struct us_data *us = host_to_us(srb->device->host);
404 int result;
406 usb_stor_dbg(us, "%s called\n", __func__);
408 result = usb_stor_port_reset(us);
409 return result < 0 ? FAILED : SUCCESS;
412 /* Report a driver-initiated device reset to the SCSI layer.
413 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
414 * The caller must own the SCSI host lock. */
415 void usb_stor_report_device_reset(struct us_data *us)
417 int i;
418 struct Scsi_Host *host = us_to_host(us);
420 scsi_report_device_reset(host, 0, 0);
421 if (us->fflags & US_FL_SCM_MULT_TARG) {
422 for (i = 1; i < host->max_id; ++i)
423 scsi_report_device_reset(host, 0, i);
427 /* Report a driver-initiated bus reset to the SCSI layer.
428 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
429 * The caller must not own the SCSI host lock. */
430 void usb_stor_report_bus_reset(struct us_data *us)
432 struct Scsi_Host *host = us_to_host(us);
434 scsi_lock(host);
435 scsi_report_bus_reset(host, 0);
436 scsi_unlock(host);
439 /***********************************************************************
440 * /proc/scsi/ functions
441 ***********************************************************************/
443 static int write_info(struct Scsi_Host *host, char *buffer, int length)
445 /* if someone is sending us data, just throw it away */
446 return length;
449 /* we use this macro to help us write into the buffer */
450 #undef SPRINTF
451 #define SPRINTF(args...) seq_printf(m, ## args)
453 static int show_info (struct seq_file *m, struct Scsi_Host *host)
455 struct us_data *us = host_to_us(host);
456 const char *string;
458 /* print the controller name */
459 SPRINTF(" Host scsi%d: usb-storage\n", host->host_no);
461 /* print product, vendor, and serial number strings */
462 if (us->pusb_dev->manufacturer)
463 string = us->pusb_dev->manufacturer;
464 else if (us->unusual_dev->vendorName)
465 string = us->unusual_dev->vendorName;
466 else
467 string = "Unknown";
468 SPRINTF(" Vendor: %s\n", string);
469 if (us->pusb_dev->product)
470 string = us->pusb_dev->product;
471 else if (us->unusual_dev->productName)
472 string = us->unusual_dev->productName;
473 else
474 string = "Unknown";
475 SPRINTF(" Product: %s\n", string);
476 if (us->pusb_dev->serial)
477 string = us->pusb_dev->serial;
478 else
479 string = "None";
480 SPRINTF("Serial Number: %s\n", string);
482 /* show the protocol and transport */
483 SPRINTF(" Protocol: %s\n", us->protocol_name);
484 SPRINTF(" Transport: %s\n", us->transport_name);
486 /* show the device flags */
487 SPRINTF(" Quirks:");
489 #define US_FLAG(name, value) \
490 if (us->fflags & value) seq_printf(m, " " #name);
491 US_DO_ALL_FLAGS
492 #undef US_FLAG
493 seq_putc(m, '\n');
494 return 0;
497 /***********************************************************************
498 * Sysfs interface
499 ***********************************************************************/
501 /* Output routine for the sysfs max_sectors file */
502 static ssize_t max_sectors_show(struct device *dev, struct device_attribute *attr, char *buf)
504 struct scsi_device *sdev = to_scsi_device(dev);
506 return sprintf(buf, "%u\n", queue_max_hw_sectors(sdev->request_queue));
509 /* Input routine for the sysfs max_sectors file */
510 static ssize_t max_sectors_store(struct device *dev, struct device_attribute *attr, const char *buf,
511 size_t count)
513 struct scsi_device *sdev = to_scsi_device(dev);
514 unsigned short ms;
516 if (sscanf(buf, "%hu", &ms) > 0) {
517 blk_queue_max_hw_sectors(sdev->request_queue, ms);
518 return count;
520 return -EINVAL;
522 static DEVICE_ATTR_RW(max_sectors);
524 static struct device_attribute *sysfs_device_attr_list[] = {
525 &dev_attr_max_sectors,
526 NULL,
530 * this defines our host template, with which we'll allocate hosts
533 struct scsi_host_template usb_stor_host_template = {
534 /* basic userland interface stuff */
535 .name = "usb-storage",
536 .proc_name = "usb-storage",
537 .show_info = show_info,
538 .write_info = write_info,
539 .info = host_info,
541 /* command interface -- queued only */
542 .queuecommand = queuecommand,
544 /* error and abort handlers */
545 .eh_abort_handler = command_abort,
546 .eh_device_reset_handler = device_reset,
547 .eh_bus_reset_handler = bus_reset,
549 /* queue commands only, only one command per LUN */
550 .can_queue = 1,
551 .cmd_per_lun = 1,
553 /* unknown initiator id */
554 .this_id = -1,
556 .slave_alloc = slave_alloc,
557 .slave_configure = slave_configure,
558 .target_alloc = target_alloc,
560 /* lots of sg segments can be handled */
561 .sg_tablesize = SCSI_MAX_SG_CHAIN_SEGMENTS,
563 /* limit the total size of a transfer to 120 KB */
564 .max_sectors = 240,
566 /* merge commands... this seems to help performance, but
567 * periodically someone should test to see which setting is more
568 * optimal.
570 .use_clustering = 1,
572 /* emulated HBA */
573 .emulated = 1,
575 /* we do our own delay after a device or bus reset */
576 .skip_settle_delay = 1,
578 /* sysfs device attributes */
579 .sdev_attrs = sysfs_device_attr_list,
581 /* module management */
582 .module = THIS_MODULE
585 /* To Report "Illegal Request: Invalid Field in CDB */
586 unsigned char usb_stor_sense_invalidCDB[18] = {
587 [0] = 0x70, /* current error */
588 [2] = ILLEGAL_REQUEST, /* Illegal Request = 0x05 */
589 [7] = 0x0a, /* additional length */
590 [12] = 0x24 /* Invalid Field in CDB */
592 EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);