mm-only debug patch...
[mmotm.git] / drivers / usb / storage / scsiglue.c
blobe5e6df39e73707989711ea0284a4109d56409b44
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/slab.h>
47 #include <linux/module.h>
48 #include <linux/mutex.h>
50 #include <scsi/scsi.h>
51 #include <scsi/scsi_cmnd.h>
52 #include <scsi/scsi_devinfo.h>
53 #include <scsi/scsi_device.h>
54 #include <scsi/scsi_eh.h>
56 #include "usb.h"
57 #include "scsiglue.h"
58 #include "debug.h"
59 #include "transport.h"
60 #include "protocol.h"
62 /* Vendor IDs for companies that seem to include the READ CAPACITY bug
63 * in all their devices
65 #define VENDOR_ID_NOKIA 0x0421
66 #define VENDOR_ID_NIKON 0x04b0
67 #define VENDOR_ID_PENTAX 0x0a17
68 #define VENDOR_ID_MOTOROLA 0x22b8
70 /***********************************************************************
71 * Host functions
72 ***********************************************************************/
74 static const char* host_info(struct Scsi_Host *host)
76 struct us_data *us = host_to_us(host);
77 return us->scsi_name;
80 static int slave_alloc (struct scsi_device *sdev)
82 struct us_data *us = host_to_us(sdev->host);
85 * Set the INQUIRY transfer length to 36. We don't use any of
86 * the extra data and many devices choke if asked for more or
87 * less than 36 bytes.
89 sdev->inquiry_len = 36;
91 /* USB has unusual DMA-alignment requirements: Although the
92 * starting address of each scatter-gather element doesn't matter,
93 * the length of each element except the last must be divisible
94 * by the Bulk maxpacket value. There's currently no way to
95 * express this by block-layer constraints, so we'll cop out
96 * and simply require addresses to be aligned at 512-byte
97 * boundaries. This is okay since most block I/O involves
98 * hardware sectors that are multiples of 512 bytes in length,
99 * and since host controllers up through USB 2.0 have maxpacket
100 * values no larger than 512.
102 * But it doesn't suffice for Wireless USB, where Bulk maxpacket
103 * values can be as large as 2048. To make that work properly
104 * will require changes to the block layer.
106 blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
109 * The UFI spec treates the Peripheral Qualifier bits in an
110 * INQUIRY result as reserved and requires devices to set them
111 * to 0. However the SCSI spec requires these bits to be set
112 * to 3 to indicate when a LUN is not present.
114 * Let the scanning code know if this target merely sets
115 * Peripheral Device Type to 0x1f to indicate no LUN.
117 if (us->subclass == US_SC_UFI)
118 sdev->sdev_target->pdt_1f_for_no_lun = 1;
120 return 0;
123 static int slave_configure(struct scsi_device *sdev)
125 struct us_data *us = host_to_us(sdev->host);
127 /* Many devices have trouble transfering more than 32KB at a time,
128 * while others have trouble with more than 64K. At this time we
129 * are limiting both to 32K (64 sectores).
131 if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
132 unsigned int max_sectors = 64;
134 if (us->fflags & US_FL_MAX_SECTORS_MIN)
135 max_sectors = PAGE_CACHE_SIZE >> 9;
136 if (queue_max_sectors(sdev->request_queue) > max_sectors)
137 blk_queue_max_sectors(sdev->request_queue,
138 max_sectors);
139 } else if (sdev->type == TYPE_TAPE) {
140 /* Tapes need much higher max_sector limits, so just
141 * raise it to the maximum possible (4 GB / 512) and
142 * let the queue segment size sort out the real limit.
144 blk_queue_max_sectors(sdev->request_queue, 0x7FFFFF);
147 /* Some USB host controllers can't do DMA; they have to use PIO.
148 * They indicate this by setting their dma_mask to NULL. For
149 * such controllers we need to make sure the block layer sets
150 * up bounce buffers in addressable memory.
152 if (!us->pusb_dev->bus->controller->dma_mask)
153 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
155 /* We can't put these settings in slave_alloc() because that gets
156 * called before the device type is known. Consequently these
157 * settings can't be overridden via the scsi devinfo mechanism. */
158 if (sdev->type == TYPE_DISK) {
160 /* Some vendors seem to put the READ CAPACITY bug into
161 * all their devices -- primarily makers of cell phones
162 * and digital cameras. Since these devices always use
163 * flash media and can be expected to have an even number
164 * of sectors, we will always enable the CAPACITY_HEURISTICS
165 * flag unless told otherwise. */
166 switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
167 case VENDOR_ID_NOKIA:
168 case VENDOR_ID_NIKON:
169 case VENDOR_ID_PENTAX:
170 case VENDOR_ID_MOTOROLA:
171 if (!(us->fflags & (US_FL_FIX_CAPACITY |
172 US_FL_CAPACITY_OK)))
173 us->fflags |= US_FL_CAPACITY_HEURISTICS;
174 break;
177 /* Disk-type devices use MODE SENSE(6) if the protocol
178 * (SubClass) is Transparent SCSI, otherwise they use
179 * MODE SENSE(10). */
180 if (us->subclass != US_SC_SCSI && us->subclass != US_SC_CYP_ATACB)
181 sdev->use_10_for_ms = 1;
183 /* Many disks only accept MODE SENSE transfer lengths of
184 * 192 bytes (that's what Windows uses). */
185 sdev->use_192_bytes_for_3f = 1;
187 /* Some devices don't like MODE SENSE with page=0x3f,
188 * which is the command used for checking if a device
189 * is write-protected. Now that we tell the sd driver
190 * to do a 192-byte transfer with this command the
191 * majority of devices work fine, but a few still can't
192 * handle it. The sd driver will simply assume those
193 * devices are write-enabled. */
194 if (us->fflags & US_FL_NO_WP_DETECT)
195 sdev->skip_ms_page_3f = 1;
197 /* A number of devices have problems with MODE SENSE for
198 * page x08, so we will skip it. */
199 sdev->skip_ms_page_8 = 1;
201 /* Some disks return the total number of blocks in response
202 * to READ CAPACITY rather than the highest block number.
203 * If this device makes that mistake, tell the sd driver. */
204 if (us->fflags & US_FL_FIX_CAPACITY)
205 sdev->fix_capacity = 1;
207 /* A few disks have two indistinguishable version, one of
208 * which reports the correct capacity and the other does not.
209 * The sd driver has to guess which is the case. */
210 if (us->fflags & US_FL_CAPACITY_HEURISTICS)
211 sdev->guess_capacity = 1;
213 /* assume SPC3 or latter devices support sense size > 18 */
214 if (sdev->scsi_level > SCSI_SPC_2)
215 us->fflags |= US_FL_SANE_SENSE;
217 /* Some devices report a SCSI revision level above 2 but are
218 * unable to handle the REPORT LUNS command (for which
219 * support is mandatory at level 3). Since we already have
220 * a Get-Max-LUN request, we won't lose much by setting the
221 * revision level down to 2. The only devices that would be
222 * affected are those with sparse LUNs. */
223 if (sdev->scsi_level > SCSI_2)
224 sdev->sdev_target->scsi_level =
225 sdev->scsi_level = SCSI_2;
227 /* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
228 * Hardware Error) when any low-level error occurs,
229 * recoverable or not. Setting this flag tells the SCSI
230 * midlayer to retry such commands, which frequently will
231 * succeed and fix the error. The worst this can lead to
232 * is an occasional series of retries that will all fail. */
233 sdev->retry_hwerror = 1;
235 /* USB disks should allow restart. Some drives spin down
236 * automatically, requiring a START-STOP UNIT command. */
237 sdev->allow_restart = 1;
239 /* Some USB cardreaders have trouble reading an sdcard's last
240 * sector in a larger then 1 sector read, since the performance
241 * impact is negible we set this flag for all USB disks */
242 sdev->last_sector_bug = 1;
244 /* Enable last-sector hacks for single-target devices using
245 * the Bulk-only transport, unless we already know the
246 * capacity will be decremented or is correct. */
247 if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
248 US_FL_SCM_MULT_TARG)) &&
249 us->protocol == US_PR_BULK)
250 us->use_last_sector_hacks = 1;
251 } else {
253 /* Non-disk-type devices don't need to blacklist any pages
254 * or to force 192-byte transfer lengths for MODE SENSE.
255 * But they do need to use MODE SENSE(10). */
256 sdev->use_10_for_ms = 1;
259 /* The CB and CBI transports have no way to pass LUN values
260 * other than the bits in the second byte of a CDB. But those
261 * bits don't get set to the LUN value if the device reports
262 * scsi_level == 0 (UNKNOWN). Hence such devices must necessarily
263 * be single-LUN.
265 if ((us->protocol == US_PR_CB || us->protocol == US_PR_CBI) &&
266 sdev->scsi_level == SCSI_UNKNOWN)
267 us->max_lun = 0;
269 /* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
270 * REMOVAL command, so suppress those commands. */
271 if (us->fflags & US_FL_NOT_LOCKABLE)
272 sdev->lockable = 0;
274 /* this is to satisfy the compiler, tho I don't think the
275 * return code is ever checked anywhere. */
276 return 0;
279 /* queue a command */
280 /* This is always called with scsi_lock(host) held */
281 static int queuecommand(struct scsi_cmnd *srb,
282 void (*done)(struct scsi_cmnd *))
284 struct us_data *us = host_to_us(srb->device->host);
286 US_DEBUGP("%s called\n", __func__);
288 /* check for state-transition errors */
289 if (us->srb != NULL) {
290 printk(KERN_ERR USB_STORAGE "Error in %s: us->srb = %p\n",
291 __func__, us->srb);
292 return SCSI_MLQUEUE_HOST_BUSY;
295 /* fail the command if we are disconnecting */
296 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
297 US_DEBUGP("Fail command during disconnect\n");
298 srb->result = DID_NO_CONNECT << 16;
299 done(srb);
300 return 0;
303 /* enqueue the command and wake up the control thread */
304 srb->scsi_done = done;
305 us->srb = srb;
306 complete(&us->cmnd_ready);
308 return 0;
311 /***********************************************************************
312 * Error handling functions
313 ***********************************************************************/
315 /* Command timeout and abort */
316 static int command_abort(struct scsi_cmnd *srb)
318 struct us_data *us = host_to_us(srb->device->host);
320 US_DEBUGP("%s called\n", __func__);
322 /* us->srb together with the TIMED_OUT, RESETTING, and ABORTING
323 * bits are protected by the host lock. */
324 scsi_lock(us_to_host(us));
326 /* Is this command still active? */
327 if (us->srb != srb) {
328 scsi_unlock(us_to_host(us));
329 US_DEBUGP ("-- nothing to abort\n");
330 return FAILED;
333 /* Set the TIMED_OUT bit. Also set the ABORTING bit, but only if
334 * a device reset isn't already in progress (to avoid interfering
335 * with the reset). Note that we must retain the host lock while
336 * calling usb_stor_stop_transport(); otherwise it might interfere
337 * with an auto-reset that begins as soon as we release the lock. */
338 set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
339 if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
340 set_bit(US_FLIDX_ABORTING, &us->dflags);
341 usb_stor_stop_transport(us);
343 scsi_unlock(us_to_host(us));
345 /* Wait for the aborted command to finish */
346 wait_for_completion(&us->notify);
347 return SUCCESS;
350 /* This invokes the transport reset mechanism to reset the state of the
351 * device */
352 static int device_reset(struct scsi_cmnd *srb)
354 struct us_data *us = host_to_us(srb->device->host);
355 int result;
357 US_DEBUGP("%s called\n", __func__);
359 /* lock the device pointers and do the reset */
360 mutex_lock(&(us->dev_mutex));
361 result = us->transport_reset(us);
362 mutex_unlock(&us->dev_mutex);
364 return result < 0 ? FAILED : SUCCESS;
367 /* Simulate a SCSI bus reset by resetting the device's USB port. */
368 static int bus_reset(struct scsi_cmnd *srb)
370 struct us_data *us = host_to_us(srb->device->host);
371 int result;
373 US_DEBUGP("%s called\n", __func__);
374 result = usb_stor_port_reset(us);
375 return result < 0 ? FAILED : SUCCESS;
378 /* Report a driver-initiated device reset to the SCSI layer.
379 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
380 * The caller must own the SCSI host lock. */
381 void usb_stor_report_device_reset(struct us_data *us)
383 int i;
384 struct Scsi_Host *host = us_to_host(us);
386 scsi_report_device_reset(host, 0, 0);
387 if (us->fflags & US_FL_SCM_MULT_TARG) {
388 for (i = 1; i < host->max_id; ++i)
389 scsi_report_device_reset(host, 0, i);
393 /* Report a driver-initiated bus reset to the SCSI layer.
394 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
395 * The caller must not own the SCSI host lock. */
396 void usb_stor_report_bus_reset(struct us_data *us)
398 struct Scsi_Host *host = us_to_host(us);
400 scsi_lock(host);
401 scsi_report_bus_reset(host, 0);
402 scsi_unlock(host);
405 /***********************************************************************
406 * /proc/scsi/ functions
407 ***********************************************************************/
409 /* we use this macro to help us write into the buffer */
410 #undef SPRINTF
411 #define SPRINTF(args...) \
412 do { if (pos < buffer+length) pos += sprintf(pos, ## args); } while (0)
414 static int proc_info (struct Scsi_Host *host, char *buffer,
415 char **start, off_t offset, int length, int inout)
417 struct us_data *us = host_to_us(host);
418 char *pos = buffer;
419 const char *string;
421 /* if someone is sending us data, just throw it away */
422 if (inout)
423 return length;
425 /* print the controller name */
426 SPRINTF(" Host scsi%d: usb-storage\n", host->host_no);
428 /* print product, vendor, and serial number strings */
429 if (us->pusb_dev->manufacturer)
430 string = us->pusb_dev->manufacturer;
431 else if (us->unusual_dev->vendorName)
432 string = us->unusual_dev->vendorName;
433 else
434 string = "Unknown";
435 SPRINTF(" Vendor: %s\n", string);
436 if (us->pusb_dev->product)
437 string = us->pusb_dev->product;
438 else if (us->unusual_dev->productName)
439 string = us->unusual_dev->productName;
440 else
441 string = "Unknown";
442 SPRINTF(" Product: %s\n", string);
443 if (us->pusb_dev->serial)
444 string = us->pusb_dev->serial;
445 else
446 string = "None";
447 SPRINTF("Serial Number: %s\n", string);
449 /* show the protocol and transport */
450 SPRINTF(" Protocol: %s\n", us->protocol_name);
451 SPRINTF(" Transport: %s\n", us->transport_name);
453 /* show the device flags */
454 if (pos < buffer + length) {
455 pos += sprintf(pos, " Quirks:");
457 #define US_FLAG(name, value) \
458 if (us->fflags & value) pos += sprintf(pos, " " #name);
459 US_DO_ALL_FLAGS
460 #undef US_FLAG
462 *(pos++) = '\n';
466 * Calculate start of next buffer, and return value.
468 *start = buffer + offset;
470 if ((pos - buffer) < offset)
471 return (0);
472 else if ((pos - buffer - offset) < length)
473 return (pos - buffer - offset);
474 else
475 return (length);
478 /***********************************************************************
479 * Sysfs interface
480 ***********************************************************************/
482 /* Output routine for the sysfs max_sectors file */
483 static ssize_t show_max_sectors(struct device *dev, struct device_attribute *attr, char *buf)
485 struct scsi_device *sdev = to_scsi_device(dev);
487 return sprintf(buf, "%u\n", queue_max_sectors(sdev->request_queue));
490 /* Input routine for the sysfs max_sectors file */
491 static ssize_t store_max_sectors(struct device *dev, struct device_attribute *attr, const char *buf,
492 size_t count)
494 struct scsi_device *sdev = to_scsi_device(dev);
495 unsigned short ms;
497 if (sscanf(buf, "%hu", &ms) > 0 && ms <= SCSI_DEFAULT_MAX_SECTORS) {
498 blk_queue_max_sectors(sdev->request_queue, ms);
499 return strlen(buf);
501 return -EINVAL;
504 static DEVICE_ATTR(max_sectors, S_IRUGO | S_IWUSR, show_max_sectors,
505 store_max_sectors);
507 static struct device_attribute *sysfs_device_attr_list[] = {
508 &dev_attr_max_sectors,
509 NULL,
513 * this defines our host template, with which we'll allocate hosts
516 struct scsi_host_template usb_stor_host_template = {
517 /* basic userland interface stuff */
518 .name = "usb-storage",
519 .proc_name = "usb-storage",
520 .proc_info = proc_info,
521 .info = host_info,
523 /* command interface -- queued only */
524 .queuecommand = queuecommand,
526 /* error and abort handlers */
527 .eh_abort_handler = command_abort,
528 .eh_device_reset_handler = device_reset,
529 .eh_bus_reset_handler = bus_reset,
531 /* queue commands only, only one command per LUN */
532 .can_queue = 1,
533 .cmd_per_lun = 1,
535 /* unknown initiator id */
536 .this_id = -1,
538 .slave_alloc = slave_alloc,
539 .slave_configure = slave_configure,
541 /* lots of sg segments can be handled */
542 .sg_tablesize = SG_ALL,
544 /* limit the total size of a transfer to 120 KB */
545 .max_sectors = 240,
547 /* merge commands... this seems to help performance, but
548 * periodically someone should test to see which setting is more
549 * optimal.
551 .use_clustering = 1,
553 /* emulated HBA */
554 .emulated = 1,
556 /* we do our own delay after a device or bus reset */
557 .skip_settle_delay = 1,
559 /* sysfs device attributes */
560 .sdev_attrs = sysfs_device_attr_list,
562 /* module management */
563 .module = THIS_MODULE
566 /* To Report "Illegal Request: Invalid Field in CDB */
567 unsigned char usb_stor_sense_invalidCDB[18] = {
568 [0] = 0x70, /* current error */
569 [2] = ILLEGAL_REQUEST, /* Illegal Request = 0x05 */
570 [7] = 0x0a, /* additional length */
571 [12] = 0x24 /* Invalid Field in CDB */
573 EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);