blob: f40779b13a20cac1f7679a81f7a7f4cb8f641ae6 [file] [log] [blame]
Tom Rini10e47792018-05-06 17:58:06 -04001// SPDX-License-Identifier: GPL-2.0+
Lukasz Majewski8647cb52013-03-05 12:10:15 +01002/*
3 * storage_common.c -- Common definitions for mass storage functionality
4 *
5 * Copyright (C) 2003-2008 Alan Stern
6 * Copyeight (C) 2009 Samsung Electronics
7 * Author: Michal Nazarewicz (m.nazarewicz@samsung.com)
8 *
9 * Ported to u-boot:
10 * Andrzej Pietrasiewicz <andrzej.p@samsung.com>
11 *
12 * Code refactoring & cleanup:
13 * Ɓukasz Majewski <l.majewski@samsung.com>
Lukasz Majewski8647cb52013-03-05 12:10:15 +010014 */
15
16
17/*
18 * This file requires the following identifiers used in USB strings to
19 * be defined (each of type pointer to char):
20 * - fsg_string_manufacturer -- name of the manufacturer
21 * - fsg_string_product -- name of the product
22 * - fsg_string_serial -- product's serial
23 * - fsg_string_config -- name of the configuration
24 * - fsg_string_interface -- name of the interface
25 * The first four are only needed when FSG_DESCRIPTORS_DEVICE_STRINGS
26 * macro is defined prior to including this file.
27 */
28
29/*
30 * When FSG_NO_INTR_EP is defined fsg_fs_intr_in_desc and
31 * fsg_hs_intr_in_desc objects as well as
32 * FSG_FS_FUNCTION_PRE_EP_ENTRIES and FSG_HS_FUNCTION_PRE_EP_ENTRIES
33 * macros are not defined.
34 *
35 * When FSG_NO_DEVICE_STRINGS is defined FSG_STRING_MANUFACTURER,
36 * FSG_STRING_PRODUCT, FSG_STRING_SERIAL and FSG_STRING_CONFIG are not
37 * defined (as well as corresponding entries in string tables are
38 * missing) and FSG_STRING_INTERFACE has value of zero.
39 *
40 * When FSG_NO_OTG is defined fsg_otg_desc won't be defined.
41 */
42
43/*
44 * When FSG_BUFFHD_STATIC_BUFFER is defined when this file is included
45 * the fsg_buffhd structure's buf field will be an array of FSG_BUFLEN
46 * characters rather then a pointer to void.
47 */
48
49
50/* #include <asm/unaligned.h> */
51
52
53/*
54 * Thanks to NetChip Technologies for donating this product ID.
55 *
56 * DO NOT REUSE THESE IDs with any other driver!! Ever!!
57 * Instead: allocate your own, using normal USB-IF procedures.
58 */
59#define FSG_VENDOR_ID 0x0525 /* NetChip */
60#define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
61
62/*-------------------------------------------------------------------------*/
63
64#ifndef DEBUG
65#undef VERBOSE_DEBUG
66#undef DUMP_MSGS
67#endif /* !DEBUG */
68
69#ifdef VERBOSE_DEBUG
70#define VLDBG LDBG
71#else
72#define VLDBG(lun, fmt, args...) do { } while (0)
73#endif /* VERBOSE_DEBUG */
74
75/*
76#define LDBG(lun, fmt, args...) dev_dbg (&(lun)->dev, fmt, ## args)
77#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
78#define LWARN(lun, fmt, args...) dev_warn(&(lun)->dev, fmt, ## args)
79#define LINFO(lun, fmt, args...) dev_info(&(lun)->dev, fmt, ## args)
80*/
81
82#define LDBG(lun, fmt, args...) do { } while (0)
83#define LERROR(lun, fmt, args...) do { } while (0)
84#define LWARN(lun, fmt, args...) do { } while (0)
85#define LINFO(lun, fmt, args...) do { } while (0)
86
87/*
88 * Keep those macros in sync with those in
89 * include/linux/usb/composite.h or else GCC will complain. If they
90 * are identical (the same names of arguments, white spaces in the
91 * same places) GCC will allow redefinition otherwise (even if some
92 * white space is removed or added) warning will be issued.
93 *
94 * Those macros are needed here because File Storage Gadget does not
95 * include the composite.h header. For composite gadgets those macros
96 * are redundant since composite.h is included any way.
97 *
98 * One could check whether those macros are already defined (which
99 * would indicate composite.h had been included) or not (which would
100 * indicate we were in FSG) but this is not done because a warning is
101 * desired if definitions here differ from the ones in composite.h.
102 *
103 * We want the definitions to match and be the same in File Storage
104 * Gadget as well as Mass Storage Function (and so composite gadgets
105 * using MSF). If someone changes them in composite.h it will produce
106 * a warning in this file when building MSF.
107 */
108
109#define DBG(d, fmt, args...) debug(fmt , ## args)
110#define VDBG(d, fmt, args...) debug(fmt , ## args)
111/* #define ERROR(d, fmt, args...) printf(fmt , ## args) */
112/* #define WARNING(d, fmt, args...) printf(fmt , ## args) */
113/* #define INFO(d, fmt, args...) printf(fmt , ## args) */
114
115/* #define DBG(d, fmt, args...) do { } while (0) */
116/* #define VDBG(d, fmt, args...) do { } while (0) */
117#define ERROR(d, fmt, args...) do { } while (0)
118#define WARNING(d, fmt, args...) do { } while (0)
119#define INFO(d, fmt, args...) do { } while (0)
120
121#ifdef DUMP_MSGS
122
123/* dump_msg(fsg, const char * label, const u8 * buf, unsigned length); */
124# define dump_msg(fsg, label, buf, length) do { \
125 if (length < 512) { \
126 DBG(fsg, "%s, length %u:\n", label, length); \
Alexey Brodkin2d2fa492018-06-05 17:17:57 +0300127 print_hex_dump("", DUMP_PREFIX_OFFSET, \
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100128 16, 1, buf, length, 0); \
129 } \
130} while (0)
131
132# define dump_cdb(fsg) do { } while (0)
133
134#else
135
136# define dump_msg(fsg, /* const char * */ label, \
137 /* const u8 * */ buf, /* unsigned */ length) do { } while (0)
138
139# ifdef VERBOSE_DEBUG
140
141# define dump_cdb(fsg) \
Alexey Brodkin2d2fa492018-06-05 17:17:57 +0300142 print_hex_dump("SCSI CDB: ", DUMP_PREFIX_NONE, \
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100143 16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \
144
145# else
146
147# define dump_cdb(fsg) do { } while (0)
148
149# endif /* VERBOSE_DEBUG */
150
151#endif /* DUMP_MSGS */
152
153/*-------------------------------------------------------------------------*/
154
155/* SCSI device types */
156#define TYPE_DISK 0x00
157#define TYPE_CDROM 0x05
158
159/* USB protocol value = the transport method */
160#define USB_PR_CBI 0x00 /* Control/Bulk/Interrupt */
161#define USB_PR_CB 0x01 /* Control/Bulk w/o interrupt */
162#define USB_PR_BULK 0x50 /* Bulk-only */
163
164/* USB subclass value = the protocol encapsulation */
165#define USB_SC_RBC 0x01 /* Reduced Block Commands (flash) */
166#define USB_SC_8020 0x02 /* SFF-8020i, MMC-2, ATAPI (CD-ROM) */
167#define USB_SC_QIC 0x03 /* QIC-157 (tape) */
168#define USB_SC_UFI 0x04 /* UFI (floppy) */
169#define USB_SC_8070 0x05 /* SFF-8070i (removable) */
170#define USB_SC_SCSI 0x06 /* Transparent SCSI */
171
172/* Bulk-only data structures */
173
174/* Command Block Wrapper */
175struct fsg_bulk_cb_wrap {
176 __le32 Signature; /* Contains 'USBC' */
177 u32 Tag; /* Unique per command id */
178 __le32 DataTransferLength; /* Size of the data */
179 u8 Flags; /* Direction in bit 7 */
180 u8 Lun; /* LUN (normally 0) */
181 u8 Length; /* Of the CDB, <= MAX_COMMAND_SIZE */
182 u8 CDB[16]; /* Command Data Block */
183};
184
185#define USB_BULK_CB_WRAP_LEN 31
186#define USB_BULK_CB_SIG 0x43425355 /* Spells out USBC */
187#define USB_BULK_IN_FLAG 0x80
188
189/* Command Status Wrapper */
190struct bulk_cs_wrap {
191 __le32 Signature; /* Should = 'USBS' */
192 u32 Tag; /* Same as original command */
193 __le32 Residue; /* Amount not transferred */
194 u8 Status; /* See below */
195};
196
197#define USB_BULK_CS_WRAP_LEN 13
198#define USB_BULK_CS_SIG 0x53425355 /* Spells out 'USBS' */
199#define USB_STATUS_PASS 0
200#define USB_STATUS_FAIL 1
201#define USB_STATUS_PHASE_ERROR 2
202
203/* Bulk-only class specific requests */
204#define USB_BULK_RESET_REQUEST 0xff
205#define USB_BULK_GET_MAX_LUN_REQUEST 0xfe
206
207/* CBI Interrupt data structure */
208struct interrupt_data {
209 u8 bType;
210 u8 bValue;
211};
212
213#define CBI_INTERRUPT_DATA_LEN 2
214
215/* CBI Accept Device-Specific Command request */
216#define USB_CBI_ADSC_REQUEST 0x00
217
218/* Length of a SCSI Command Data Block */
219#define MAX_COMMAND_SIZE 16
220
221/* SCSI commands that we recognize */
222#define SC_FORMAT_UNIT 0x04
223#define SC_INQUIRY 0x12
224#define SC_MODE_SELECT_6 0x15
225#define SC_MODE_SELECT_10 0x55
226#define SC_MODE_SENSE_6 0x1a
227#define SC_MODE_SENSE_10 0x5a
228#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e
229#define SC_READ_6 0x08
230#define SC_READ_10 0x28
231#define SC_READ_12 0xa8
232#define SC_READ_CAPACITY 0x25
233#define SC_READ_FORMAT_CAPACITIES 0x23
234#define SC_READ_HEADER 0x44
235#define SC_READ_TOC 0x43
236#define SC_RELEASE 0x17
237#define SC_REQUEST_SENSE 0x03
238#define SC_RESERVE 0x16
239#define SC_SEND_DIAGNOSTIC 0x1d
240#define SC_START_STOP_UNIT 0x1b
241#define SC_SYNCHRONIZE_CACHE 0x35
242#define SC_TEST_UNIT_READY 0x00
243#define SC_VERIFY 0x2f
244#define SC_WRITE_6 0x0a
245#define SC_WRITE_10 0x2a
246#define SC_WRITE_12 0xaa
247
248/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
249#define SS_NO_SENSE 0
250#define SS_COMMUNICATION_FAILURE 0x040800
251#define SS_INVALID_COMMAND 0x052000
252#define SS_INVALID_FIELD_IN_CDB 0x052400
253#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
254#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
255#define SS_MEDIUM_NOT_PRESENT 0x023a00
256#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
257#define SS_NOT_READY_TO_READY_TRANSITION 0x062800
258#define SS_RESET_OCCURRED 0x062900
259#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
260#define SS_UNRECOVERED_READ_ERROR 0x031100
261#define SS_WRITE_ERROR 0x030c02
262#define SS_WRITE_PROTECTED 0x072700
263
264#define SK(x) ((u8) ((x) >> 16)) /* Sense Key byte, etc. */
265#define ASC(x) ((u8) ((x) >> 8))
266#define ASCQ(x) ((u8) (x))
267
268struct device_attribute { int i; };
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100269#define ETOOSMALL 525
270
271#include <usb_mass_storage.h>
Simon Glass9bc15642020-02-03 07:36:16 -0700272#include <dm/device_compat.h>
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100273
274/*-------------------------------------------------------------------------*/
275
276struct fsg_lun {
277 loff_t file_length;
278 loff_t num_sectors;
279
280 unsigned int initially_ro:1;
281 unsigned int ro:1;
282 unsigned int removable:1;
283 unsigned int cdrom:1;
284 unsigned int prevent_medium_removal:1;
285 unsigned int registered:1;
286 unsigned int info_valid:1;
287 unsigned int nofua:1;
288
289 u32 sense_data;
290 u32 sense_data_info;
291 u32 unit_attention_data;
292
293 struct device dev;
294};
295
296#define fsg_lun_is_open(curlun) ((curlun)->filp != NULL)
297#if 0
298static struct fsg_lun *fsg_lun_from_dev(struct device *dev)
299{
300 return container_of(dev, struct fsg_lun, dev);
301}
302#endif
303
304/* Big enough to hold our biggest descriptor */
305#define EP0_BUFSIZE 256
306#define DELAYED_STATUS (EP0_BUFSIZE + 999) /* An impossibly large value */
307
308/* Number of buffers we will use. 2 is enough for double-buffering */
309#define FSG_NUM_BUFFERS 2
310
311/* Default size of buffer length. */
Marek Vasut91215be2017-10-19 21:45:53 +0200312#define FSG_BUFLEN ((u32)131072)
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100313
314/* Maximal number of LUNs supported in mass storage function */
315#define FSG_MAX_LUNS 8
316
317enum fsg_buffer_state {
318 BUF_STATE_EMPTY = 0,
319 BUF_STATE_FULL,
320 BUF_STATE_BUSY
321};
322
323struct fsg_buffhd {
324#ifdef FSG_BUFFHD_STATIC_BUFFER
325 char buf[FSG_BUFLEN];
326#else
327 void *buf;
328#endif
329 enum fsg_buffer_state state;
330 struct fsg_buffhd *next;
331
332 /*
333 * The NetChip 2280 is faster, and handles some protocol faults
334 * better, if we don't submit any short bulk-out read requests.
335 * So we will record the intended request length here.
336 */
337 unsigned int bulk_out_intended_length;
338
339 struct usb_request *inreq;
340 int inreq_busy;
341 struct usb_request *outreq;
342 int outreq_busy;
343};
344
345enum fsg_state {
346 /* This one isn't used anywhere */
347 FSG_STATE_COMMAND_PHASE = -10,
348 FSG_STATE_DATA_PHASE,
349 FSG_STATE_STATUS_PHASE,
350
351 FSG_STATE_IDLE = 0,
352 FSG_STATE_ABORT_BULK_OUT,
353 FSG_STATE_RESET,
354 FSG_STATE_INTERFACE_CHANGE,
355 FSG_STATE_CONFIG_CHANGE,
356 FSG_STATE_DISCONNECT,
357 FSG_STATE_EXIT,
358 FSG_STATE_TERMINATED
359};
360
361enum data_direction {
362 DATA_DIR_UNKNOWN = 0,
363 DATA_DIR_FROM_HOST,
364 DATA_DIR_TO_HOST,
365 DATA_DIR_NONE
366};
367
368/*-------------------------------------------------------------------------*/
369
370static inline u32 get_unaligned_be24(u8 *buf)
371{
372 return 0xffffff & (u32) get_unaligned_be32(buf - 1);
373}
374
375/*-------------------------------------------------------------------------*/
376
377enum {
378#ifndef FSG_NO_DEVICE_STRINGS
379 FSG_STRING_MANUFACTURER = 1,
380 FSG_STRING_PRODUCT,
381 FSG_STRING_SERIAL,
382 FSG_STRING_CONFIG,
383#endif
384 FSG_STRING_INTERFACE
385};
386
387#ifndef FSG_NO_OTG
388static struct usb_otg_descriptor
389fsg_otg_desc = {
390 .bLength = sizeof fsg_otg_desc,
391 .bDescriptorType = USB_DT_OTG,
392
393 .bmAttributes = USB_OTG_SRP,
394};
395#endif
396
397/* There is only one interface. */
398
399static struct usb_interface_descriptor
400fsg_intf_desc = {
401 .bLength = sizeof fsg_intf_desc,
402 .bDescriptorType = USB_DT_INTERFACE,
403
404 .bNumEndpoints = 2, /* Adjusted during fsg_bind() */
405 .bInterfaceClass = USB_CLASS_MASS_STORAGE,
406 .bInterfaceSubClass = USB_SC_SCSI, /* Adjusted during fsg_bind() */
407 .bInterfaceProtocol = USB_PR_BULK, /* Adjusted during fsg_bind() */
408 .iInterface = FSG_STRING_INTERFACE,
409};
410
411/*
412 * Three full-speed endpoint descriptors: bulk-in, bulk-out, and
413 * interrupt-in.
414 */
415
416static struct usb_endpoint_descriptor
417fsg_fs_bulk_in_desc = {
418 .bLength = USB_DT_ENDPOINT_SIZE,
419 .bDescriptorType = USB_DT_ENDPOINT,
420
421 .bEndpointAddress = USB_DIR_IN,
422 .bmAttributes = USB_ENDPOINT_XFER_BULK,
423 /* wMaxPacketSize set by autoconfiguration */
424};
425
426static struct usb_endpoint_descriptor
427fsg_fs_bulk_out_desc = {
428 .bLength = USB_DT_ENDPOINT_SIZE,
429 .bDescriptorType = USB_DT_ENDPOINT,
430
431 .bEndpointAddress = USB_DIR_OUT,
432 .bmAttributes = USB_ENDPOINT_XFER_BULK,
433 /* wMaxPacketSize set by autoconfiguration */
434};
435
436#ifndef FSG_NO_INTR_EP
437
438static struct usb_endpoint_descriptor
439fsg_fs_intr_in_desc = {
440 .bLength = USB_DT_ENDPOINT_SIZE,
441 .bDescriptorType = USB_DT_ENDPOINT,
442
443 .bEndpointAddress = USB_DIR_IN,
444 .bmAttributes = USB_ENDPOINT_XFER_INT,
445 .wMaxPacketSize = cpu_to_le16(2),
446 .bInterval = 32, /* frames -> 32 ms */
447};
448
449#ifndef FSG_NO_OTG
450# define FSG_FS_FUNCTION_PRE_EP_ENTRIES 2
451#else
452# define FSG_FS_FUNCTION_PRE_EP_ENTRIES 1
453#endif
454
455#endif
456
457static struct usb_descriptor_header *fsg_fs_function[] = {
458#ifndef FSG_NO_OTG
459 (struct usb_descriptor_header *) &fsg_otg_desc,
460#endif
461 (struct usb_descriptor_header *) &fsg_intf_desc,
462 (struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
463 (struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
464#ifndef FSG_NO_INTR_EP
465 (struct usb_descriptor_header *) &fsg_fs_intr_in_desc,
466#endif
467 NULL,
468};
469
470/*
471 * USB 2.0 devices need to expose both high speed and full speed
472 * descriptors, unless they only run at full speed.
473 *
474 * That means alternate endpoint descriptors (bigger packets)
475 * and a "device qualifier" ... plus more construction options
476 * for the configuration descriptor.
477 */
478static struct usb_endpoint_descriptor
479fsg_hs_bulk_in_desc = {
480 .bLength = USB_DT_ENDPOINT_SIZE,
481 .bDescriptorType = USB_DT_ENDPOINT,
482
483 /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
484 .bmAttributes = USB_ENDPOINT_XFER_BULK,
485 .wMaxPacketSize = cpu_to_le16(512),
486};
487
488static struct usb_endpoint_descriptor
489fsg_hs_bulk_out_desc = {
490 .bLength = USB_DT_ENDPOINT_SIZE,
491 .bDescriptorType = USB_DT_ENDPOINT,
492
493 /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
494 .bmAttributes = USB_ENDPOINT_XFER_BULK,
495 .wMaxPacketSize = cpu_to_le16(512),
496 .bInterval = 1, /* NAK every 1 uframe */
497};
498
499#ifndef FSG_NO_INTR_EP
500
501static struct usb_endpoint_descriptor
502fsg_hs_intr_in_desc = {
503 .bLength = USB_DT_ENDPOINT_SIZE,
504 .bDescriptorType = USB_DT_ENDPOINT,
505
506 /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
507 .bmAttributes = USB_ENDPOINT_XFER_INT,
508 .wMaxPacketSize = cpu_to_le16(2),
509 .bInterval = 9, /* 2**(9-1) = 256 uframes -> 32 ms */
510};
511
512#ifndef FSG_NO_OTG
513# define FSG_HS_FUNCTION_PRE_EP_ENTRIES 2
514#else
515# define FSG_HS_FUNCTION_PRE_EP_ENTRIES 1
516#endif
517
518#endif
519
520static struct usb_descriptor_header *fsg_hs_function[] = {
521#ifndef FSG_NO_OTG
522 (struct usb_descriptor_header *) &fsg_otg_desc,
523#endif
524 (struct usb_descriptor_header *) &fsg_intf_desc,
525 (struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
526 (struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
527#ifndef FSG_NO_INTR_EP
528 (struct usb_descriptor_header *) &fsg_hs_intr_in_desc,
529#endif
530 NULL,
531};
532
533/* Maxpacket and other transfer characteristics vary by speed. */
534static struct usb_endpoint_descriptor *
535fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
536 struct usb_endpoint_descriptor *hs)
537{
538 if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
539 return hs;
540 return fs;
541}
542
543/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
544static struct usb_string fsg_strings[] = {
545#ifndef FSG_NO_DEVICE_STRINGS
546 {FSG_STRING_MANUFACTURER, fsg_string_manufacturer},
547 {FSG_STRING_PRODUCT, fsg_string_product},
548 {FSG_STRING_SERIAL, fsg_string_serial},
549 {FSG_STRING_CONFIG, fsg_string_config},
550#endif
551 {FSG_STRING_INTERFACE, fsg_string_interface},
552 {}
553};
554
555static struct usb_gadget_strings fsg_stringtab = {
556 .language = 0x0409, /* en-us */
557 .strings = fsg_strings,
558};
559
560/*-------------------------------------------------------------------------*/
561
562/*
563 * If the next two routines are called while the gadget is registered,
564 * the caller must own fsg->filesem for writing.
565 */
566
Stephen Warren9e7d5882015-12-07 11:38:50 -0700567static int fsg_lun_open(struct fsg_lun *curlun, unsigned int num_sectors,
568 const char *filename)
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100569{
570 int ro;
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100571
572 /* R/W if we can, R/O if we must */
573 ro = curlun->initially_ro;
574
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100575 curlun->ro = ro;
Stephen Warren9e7d5882015-12-07 11:38:50 -0700576 curlun->file_length = num_sectors << 9;
577 curlun->num_sectors = num_sectors;
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100578 debug("open backing file: %s\n", filename);
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100579
Przemyslaw Marczak3dab7302013-10-23 14:30:44 +0200580 return 0;
Lukasz Majewski8647cb52013-03-05 12:10:15 +0100581}
582
583static void fsg_lun_close(struct fsg_lun *curlun)
584{
585}
586
587/*-------------------------------------------------------------------------*/
588
589/*
590 * Sync the file data, don't bother with the metadata.
591 * This code was copied from fs/buffer.c:sys_fdatasync().
592 */
593static int fsg_lun_fsync_sub(struct fsg_lun *curlun)
594{
595 return 0;
596}
597
598static void store_cdrom_address(u8 *dest, int msf, u32 addr)
599{
600 if (msf) {
601 /* Convert to Minutes-Seconds-Frames */
602 addr >>= 2; /* Convert to 2048-byte frames */
603 addr += 2*75; /* Lead-in occupies 2 seconds */
604 dest[3] = addr % 75; /* Frames */
605 addr /= 75;
606 dest[2] = addr % 60; /* Seconds */
607 addr /= 60;
608 dest[1] = addr; /* Minutes */
609 dest[0] = 0; /* Reserved */
610 } else {
611 /* Absolute sector */
612 put_unaligned_be32(addr, dest);
613 }
614}
615
616/*-------------------------------------------------------------------------*/