diff options
Diffstat (limited to 'drivers/usb/gadget/f_mass_storage.c')
| -rw-r--r-- | drivers/usb/gadget/f_mass_storage.c | 567 |
1 files changed, 329 insertions, 238 deletions
diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c index 837aab624a46..5eaf22db7fcc 100644 --- a/drivers/usb/gadget/f_mass_storage.c +++ b/drivers/usb/gadget/f_mass_storage.c @@ -1,7 +1,9 @@ /* - * file_storage.c -- File-backed USB Storage Gadget, for USB development + * f_mass_storage.c -- Mass Storage USB Composite Function * * Copyright (C) 2003-2008 Alan Stern + * Copyright (C) 2009 Samsung Electronics + * Author: Michal Nazarewicz <m.nazarewicz@samsung.com> * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -37,37 +39,112 @@ /* - * The File-backed Storage Gadget acts as a USB Mass Storage device, - * appearing to the host as a disk drive or as a CD-ROM drive. In addition - * to providing an example of a genuinely useful gadget driver for a USB - * device, it also illustrates a technique of double-buffering for increased - * throughput. Last but not least, it gives an easy way to probe the - * behavior of the Mass Storage drivers in a USB host. + * The Mass Storage Function acts as a USB Mass Storage device, + * appearing to the host as a disk drive or as a CD-ROM drive. In + * addition to providing an example of a genuinely useful composite + * function for a USB device, it also illustrates a technique of + * double-buffering for increased throughput. * - * Backing storage is provided by a regular file or a block device, specified - * by the "file" module parameter. Access can be limited to read-only by - * setting the optional "ro" module parameter. (For CD-ROM emulation, - * access is always read-only.) The gadget will indicate that it has - * removable media if the optional "removable" module parameter is set. + * Function supports multiple logical units (LUNs). Backing storage + * for each LUN is provided by a regular file or a block device. + * Access for each LUN can be limited to read-only. Moreover, the + * function can indicate that LUN is removable and/or CD-ROM. (The + * later implies read-only access.) + * + * MSF is configured by specifying a fsg_config structure. It has the + * following fields: + * + * nluns Number of LUNs function have (anywhere from 1 + * to FSG_MAX_LUNS which is 8). + * luns An array of LUN configuration values. This + * should be filled for each LUN that + * function will include (ie. for "nluns" + * LUNs). Each element of the array has + * the following fields: + * ->filename The path to the backing file for the LUN. + * Required if LUN is not marked as + * removable. + * ->ro Flag specifying access to the LUN shall be + * read-only. This is implied if CD-ROM + * emulation is enabled as well as when + * it was impossible to open "filename" + * in R/W mode. + * ->removable Flag specifying that LUN shall be indicated as + * being removable. + * ->cdrom Flag specifying that LUN shall be reported as + * being a CD-ROM. + * + * lun_name_format A printf-like format for names of the LUN + * devices. This determines how the + * directory in sysfs will be named. + * Unless you are using several MSFs in + * a single gadget (as opposed to single + * MSF in many configurations) you may + * leave it as NULL (in which case + * "lun%d" will be used). In the format + * you can use "%d" to index LUNs for + * MSF's with more than one LUN. (Beware + * that there is only one integer given + * as an argument for the format and + * specifying invalid format may cause + * unspecified behaviour.) + * thread_name Name of the kernel thread process used by the + * MSF. You can safely set it to NULL + * (in which case default "file-storage" + * will be used). + * + * vendor_name + * product_name + * release Information used as a reply to INQUIRY + * request. To use default set to NULL, + * NULL, 0xffff respectively. The first + * field should be 8 and the second 16 + * characters or less. + * + * can_stall Set to permit function to halt bulk endpoints. + * Disabled on some USB devices known not + * to work correctly. You should set it + * to true. + * + * If "removable" is not set for a LUN then a backing file must be + * specified. If it is set, then NULL filename means the LUN's medium + * is not loaded (an empty string as "filename" in the fsg_config + * structure causes error). The CD-ROM emulation includes a single + * data track and no audio tracks; hence there need be only one + * backing file per LUN. Note also that the CD-ROM block length is + * set to 512 rather than the more common value 2048. + * + * + * MSF includes support for module parameters. If gadget using it + * decides to use it, the following module parameters will be + * available: + * + * file=filename[,filename...] + * Names of the files or block devices used for + * backing storage. + * ro=b[,b...] Default false, boolean for read-only access. + * removable=b[,b...] + * Default true, boolean for removable media. + * cdrom=b[,b...] Default false, boolean for whether to emulate + * a CD-ROM drive. + * luns=N Default N = number of filenames, number of + * LUNs to support. + * stall Default determined according to the type of + * USB device controller (usually true), + * boolean to permit the driver to halt + * bulk endpoints. + * + * The module parameters may be prefixed with some string. You need + * to consult gadget's documentation or source to verify whether it is + * using those module parameters and if it does what are the prefixes + * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is + * the prefix). * - * There is support for multiple logical units (LUNs), each of which has - * its own backing file. The number of LUNs can be set using the optional - * "luns" module parameter (anywhere from 1 to 8), and the corresponding - * files are specified using comma-separated lists for "file" and "ro". - * The default number of LUNs is taken from the number of "file" elements; - * it is 1 if "file" is not given. If "removable" is not set then a backing - * file must be specified for each LUN. If it is set, then an unspecified - * or empty backing filename means the LUN's medium is not loaded. Ideally - * each LUN would be settable independently as a disk drive or a CD-ROM - * drive, but currently all LUNs have to be the same type. The CD-ROM - * emulation includes a single data track and no audio tracks; hence there - * need be only one backing file per LUN. Note also that the CD-ROM block - * length is set to 512 rather than the more common value 2048. * * Requirements are modest; only a bulk-in and a bulk-out endpoint are - * needed (an interrupt-out endpoint is also needed for CBI). The memory - * requirement amounts to two 16K buffers, size configurable by a parameter. - * Support is included for both full-speed and high-speed operation. + * needed. The memory requirement amounts to two 16K buffers, size + * configurable by a parameter. Support is included for both + * full-speed and high-speed operation. * * Note that the driver is slightly non-portable in that it assumes a * single memory/DMA buffer will be useable for bulk-in, bulk-out, and @@ -75,39 +152,28 @@ * issue, but there may be some with hardware restrictions that prevent * a buffer from being used by more than one endpoint. * - * Module options: * - * file=filename[,filename...] - * Required if "removable" is not set, names of - * the files or block devices used for - * backing storage - * ro=b[,b...] Default false, booleans for read-only access - * removable Default false, boolean for removable media - * luns=N Default N = number of filenames, number of - * LUNs to support - * stall Default determined according to the type of - * USB device controller (usually true), - * boolean to permit the driver to halt - * bulk endpoints - * cdrom Default false, boolean for whether to emulate - * a CD-ROM drive + * The pathnames of the backing files and the ro settings are + * available in the attribute files "file" and "ro" in the lun<n> (or + * to be more precise in a directory which name comes from + * "lun_name_format" option!) subdirectory of the gadget's sysfs + * directory. If the "removable" option is set, writing to these + * files will simulate ejecting/loading the medium (writing an empty + * line means eject) and adjusting a write-enable tab. Changes to the + * ro setting are not allowed when the medium is loaded or if CD-ROM + * emulation is being used. * - * The pathnames of the backing files and the ro settings are available in - * the attribute files "file" and "ro" in the lun<n> subdirectory of the - * gadget's sysfs directory. If the "removable" option is set, writing to - * these files will simulate ejecting/loading the medium (writing an empty - * line means eject) and adjusting a write-enable tab. Changes to the ro - * setting are not allowed when the medium is loaded or if CD-ROM emulation - * is being used. * - * This gadget driver is heavily based on "Gadget Zero" by David Brownell. - * The driver's SCSI command interface was based on the "Information - * technology - Small Computer System Interface - 2" document from - * X3T9.2 Project 375D, Revision 10L, 7-SEP-93, available at - * <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>. The single exception - * is opcode 0x23 (READ FORMAT CAPACITIES), which was based on the - * "Universal Serial Bus Mass Storage Class UFI Command Specification" - * document, Revision 1.0, December 14, 1998, available at + * This function is heavily based on "File-backed Storage Gadget" by + * Alan Stern which in turn is heavily based on "Gadget Zero" by David + * Brownell. The driver's SCSI command interface was based on the + * "Information technology - Small Computer System Interface - 2" + * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93, + * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>. + * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which + * was based on the "Universal Serial Bus Mass Storage Class UFI + * Command Specification" document, Revision 1.0, December 14, 1998, + * available at * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>. */ @@ -115,7 +181,7 @@ /* * Driver Design * - * The FSG driver is fairly straightforward. There is a main kernel + * The MSF is fairly straightforward. There is a main kernel * thread that handles most of the work. Interrupt routines field * callbacks from the controller driver: bulk- and interrupt-request * completion notifications, endpoint-0 events, and disconnect events. @@ -138,17 +204,11 @@ * an EXIT exception. * * In normal operation the main thread is started during the gadget's - * fsg_bind() callback and stopped during fsg_unbind(). But it can also - * exit when it receives a signal, and there's no point leaving the - * gadget running when the thread is dead. So just before the thread - * exits, it deregisters the gadget driver. This makes things a little - * tricky: The driver is deregistered at two places, and the exiting - * thread can indirectly call fsg_unbind() which in turn can tell the - * thread to exit. The first problem is resolved through the use of the - * REGISTERED atomic bitflag; the driver will only be deregistered once. - * The second problem is resolved by having fsg_unbind() check - * fsg->state; it won't try to stop the thread if the state is already - * FSG_STATE_TERMINATED. + * fsg_bind() callback and stopped during fsg_unbind(). But it can + * also exit when it receives a signal, and there's no point leaving + * the gadget running when the thread is dead. At of this moment, MSF + * provides no way to deregister the gadget when thread dies -- maybe + * a callback functions is needed. * * To provide maximum throughput, the driver uses a circular pipeline of * buffer heads (struct fsg_buffhd). In principle the pipeline can be @@ -236,7 +296,7 @@ /*------------------------------------------------------------------------*/ #define FSG_DRIVER_DESC "Mass Storage Function" -#define FSG_DRIVER_VERSION "20 November 2008" +#define FSG_DRIVER_VERSION "2009/09/11" static const char fsg_string_interface[] = "Mass Storage"; @@ -307,7 +367,7 @@ struct fsg_config { struct fsg_dev { struct usb_function function; - struct usb_composite_dev*cdev; + struct usb_composite_dev *cdev; struct usb_gadget *gadget; /* Copy of cdev->gadget */ struct fsg_common *common; @@ -322,18 +382,18 @@ struct fsg_dev { const char *ep0req_name; unsigned int bulk_out_maxpacket; - enum fsg_state state; // For exception handling + enum fsg_state state; /* For exception handling */ unsigned int exception_req_tag; u8 config, new_config; - unsigned int running : 1; - unsigned int bulk_in_enabled : 1; - unsigned int bulk_out_enabled : 1; - unsigned int phase_error : 1; - unsigned int short_packet_received : 1; - unsigned int bad_lun_okay : 1; - unsigned int can_stall : 1; + unsigned int running:1; + unsigned int bulk_in_enabled:1; + unsigned int bulk_out_enabled:1; + unsigned int phase_error:1; + unsigned int short_packet_received:1; + unsigned int bad_lun_okay:1; + unsigned int can_stall:1; unsigned long atomic_bitflags; #define REGISTERED 0 @@ -461,7 +521,7 @@ static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req) if (req->status || req->actual != req->length) DBG(fsg, "%s --> %d, %u/%u\n", __func__, req->status, req->actual, req->length); - if (req->status == -ECONNRESET) // Request was cancelled + if (req->status == -ECONNRESET) /* Request was cancelled */ usb_ep_fifo_flush(ep); /* Hold the lock while we update the request and buffer states */ @@ -483,7 +543,7 @@ static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req) DBG(fsg, "%s --> %d, %u/%u\n", __func__, req->status, req->actual, bh->bulk_out_intended_length); - if (req->status == -ECONNRESET) // Request was cancelled + if (req->status == -ECONNRESET) /* Request was cancelled */ usb_ep_fifo_flush(ep); /* Hold the lock while we update the request and buffer states */ @@ -643,7 +703,7 @@ static int do_read(struct fsg_dev *fsg) /* Carry out the file reads */ amount_left = fsg->data_size_from_cmnd; if (unlikely(amount_left == 0)) - return -EIO; // No default reply + return -EIO; /* No default reply */ for (;;) { @@ -701,7 +761,7 @@ static int do_read(struct fsg_dev *fsg) } else if (nread < amount) { LDBG(curlun, "partial file read: %d/%u\n", (int) nread, amount); - nread -= (nread & 511); // Round down to a block + nread -= (nread & 511); /* Round down to a block */ } file_offset += nread; amount_left -= nread; @@ -718,7 +778,7 @@ static int do_read(struct fsg_dev *fsg) } if (amount_left == 0) - break; // No more left to read + break; /* No more left to read */ /* Send this buffer and go read some more */ bh->inreq->zero = 0; @@ -727,7 +787,7 @@ static int do_read(struct fsg_dev *fsg) fsg->common->next_buffhd_to_fill = bh->next; } - return -EIO; // No default reply + return -EIO; /* No default reply */ } @@ -751,7 +811,7 @@ static int do_write(struct fsg_dev *fsg) return -EINVAL; } spin_lock(&curlun->filp->f_lock); - curlun->filp->f_flags &= ~O_SYNC; // Default is not to wait + curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */ spin_unlock(&curlun->filp->f_lock); /* Get the starting Logical Block Address and check that it's @@ -769,7 +829,7 @@ static int do_write(struct fsg_dev *fsg) curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } - if (fsg->common->cmnd[1] & 0x08) { // FUA + if (fsg->common->cmnd[1] & 0x08) { /* FUA */ spin_lock(&curlun->filp->f_lock); curlun->filp->f_flags |= O_SYNC; spin_unlock(&curlun->filp->f_lock); @@ -834,8 +894,8 @@ static int do_write(struct fsg_dev *fsg) /* amount is always divisible by 512, hence by * the bulk-out maxpacket size */ - bh->outreq->length = bh->bulk_out_intended_length = - amount; + bh->outreq->length = amount; + bh->bulk_out_intended_length = amount; bh->outreq->short_not_ok = 1; start_transfer(fsg, fsg->bulk_out, bh->outreq, &bh->outreq_busy, &bh->state); @@ -846,7 +906,7 @@ static int do_write(struct fsg_dev *fsg) /* Write the received data to the backing file */ bh = fsg->common->next_buffhd_to_drain; if (bh->state == BUF_STATE_EMPTY && !get_some_more) - break; // We stopped early + break; /* We stopped early */ if (bh->state == BUF_STATE_FULL) { smp_rmb(); fsg->common->next_buffhd_to_drain = bh->next; @@ -878,7 +938,7 @@ static int do_write(struct fsg_dev *fsg) (unsigned long long) file_offset, (int) nwritten); if (signal_pending(current)) - return -EINTR; // Interrupted! + return -EINTR; /* Interrupted! */ if (nwritten < 0) { LDBG(curlun, "error in file write: %d\n", @@ -888,7 +948,7 @@ static int do_write(struct fsg_dev *fsg) LDBG(curlun, "partial file write: %d/%u\n", (int) nwritten, amount); nwritten -= (nwritten & 511); - // Round down to a block + /* Round down to a block */ } file_offset += nwritten; amount_left_to_write -= nwritten; @@ -916,7 +976,7 @@ static int do_write(struct fsg_dev *fsg) return rc; } - return -EIO; // No default reply + return -EIO; /* No default reply */ } @@ -976,7 +1036,7 @@ static int do_verify(struct fsg_dev *fsg) verification_length = get_unaligned_be16(&fsg->common->cmnd[7]); if (unlikely(verification_length == 0)) - return -EIO; // No default reply + return -EIO; /* No default reply */ /* Prepare to carry out the file verify */ amount_left = verification_length << 9; @@ -1029,7 +1089,7 @@ static int do_verify(struct fsg_dev *fsg) } else if (nread < amount) { LDBG(curlun, "partial file verify: %d/%u\n", (int) nread, amount); - nread -= (nread & 511); // Round down to a sector + nread -= (nread & 511); /* Round down to a sector */ } if (nread == 0) { curlun->sense_data = SS_UNRECOVERED_READ_ERROR; @@ -1054,17 +1114,17 @@ static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh) if (!curlun) { /* Unsupported LUNs are okay */ fsg->bad_lun_okay = 1; memset(buf, 0, 36); - buf[0] = 0x7f; // Unsupported, no device-type - buf[4] = 31; // Additional length + buf[0] = 0x7f; /* Unsupported, no device-type */ + buf[4] = 31; /* Additional length */ return 36; } buf[0] = curlun->cdrom ? TYPE_CDROM : TYPE_DISK; buf[1] = curlun->removable ? 0x80 : 0; - buf[2] = 2; // ANSI SCSI level 2 - buf[3] = 2; // SCSI-2 INQUIRY data format - buf[4] = 31; // Additional length - buf[5] = 0; // No special options + buf[2] = 2; /* ANSI SCSI level 2 */ + buf[3] = 2; /* SCSI-2 INQUIRY data format */ + buf[4] = 31; /* Additional length */ + buf[5] = 0; /* No special options */ buf[6] = 0; buf[7] = 0; memcpy(buf + 8, fsg->common->inquiry_string, @@ -1102,7 +1162,7 @@ static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) } #endif - if (!curlun) { // Unsupported LUNs are okay + if (!curlun) { /* Unsupported LUNs are okay */ fsg->bad_lun_okay = 1; sd = SS_LOGICAL_UNIT_NOT_SUPPORTED; sdinfo = 0; @@ -1117,10 +1177,10 @@ static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) } memset(buf, 0, 18); - buf[0] = valid | 0x70; // Valid, current error + buf[0] = valid | 0x70; /* Valid, current error */ buf[2] = SK(sd); put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */ - buf[7] = 18 - 8; // Additional sense length + buf[7] = 18 - 8; /* Additional sense length */ buf[12] = ASC(sd); buf[13] = ASCQ(sd); return 18; @@ -1209,7 +1269,7 @@ static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) int valid_page = 0; int len, limit; - if ((fsg->common->cmnd[1] & ~0x08) != 0) { // Mask away DBD + if ((fsg->common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */ curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } @@ -1228,13 +1288,13 @@ static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) * the mode data length later. */ memset(buf, 0, 8); if (mscmnd == SC_MODE_SENSE_6) { - buf[2] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA + buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */ buf += 4; limit = 255; - } else { // SC_MODE_SENSE_10 - buf[3] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA + } else { /* SC_MODE_SENSE_10 */ + buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */ buf += 8; - limit = 65535; // Should really be FSG_BUFLEN + limit = 65535; /* Should really be FSG_BUFLEN */ } /* No block descriptors */ @@ -1243,14 +1303,14 @@ static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) * is the Caching page. */ if (page_code == 0x08 || all_pages) { valid_page = 1; - buf[0] = 0x08; // Page code - buf[1] = 10; // Page length - memset(buf+2, 0, 10); // None of the fields are changeable + buf[0] = 0x08; /* Page code */ + buf[1] = 10; /* Page length */ + memset(buf+2, 0, 10); /* None of the fields are changeable */ if (!changeable_values) { - buf[2] = 0x04; // Write cache enable, - // Read cache not disabled - // No cache retention priorities + buf[2] = 0x04; /* Write cache enable, */ + /* Read cache not disabled */ + /* No cache retention priorities */ put_unaligned_be16(0xffff, &buf[4]); /* Don't disable prefetch */ /* Minimum prefetch = 0 */ @@ -1304,7 +1364,7 @@ static int do_prevent_allow(struct fsg_dev *fsg) } prevent = fsg->common->cmnd[4] & 0x01; - if ((fsg->common->cmnd[4] & ~0x01) != 0) { // Mask away Prevent + if ((fsg->common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */ curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } @@ -1323,7 +1383,7 @@ static int do_read_format_capacities(struct fsg_dev *fsg, u8 *buf = (u8 *) bh->buf; buf[0] = buf[1] = buf[2] = 0; - buf[3] = 8; // Only the Current/Maximum Capacity Descriptor + buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */ buf += 4; put_unaligned_be32(curlun->num_sectors, &buf[0]); @@ -1398,7 +1458,7 @@ static int pad_with_zeros(struct fsg_dev *fsg) u32 nsend; int rc; - bh->state = BUF_STATE_EMPTY; // For the first iteration + bh->state = BUF_STATE_EMPTY; /* For the first iteration */ fsg->usb_amount_left = nkeep + fsg->residue; while (fsg->usb_amount_left > 0) { @@ -1454,8 +1514,8 @@ static int throw_away_data(struct fsg_dev *fsg) /* amount is always divisible by 512, hence by * the bulk-out maxpacket size */ - bh->outreq->length = bh->bulk_out_intended_length = - amount; + bh->outreq->length = amount; + bh->bulk_out_intended_length = amount; bh->outreq->short_not_ok = 1; start_transfer(fsg, fsg->bulk_out, bh->outreq, &bh->outreq_busy, &bh->state); @@ -1480,7 +1540,7 @@ static int finish_reply(struct fsg_dev *fsg) switch (fsg->data_dir) { case DATA_DIR_NONE: - break; // Nothing to send + break; /* Nothing to send */ /* If we don't know whether the host wants to read or write, * this must be CB or CBI with an unknown command. We mustn't @@ -1522,14 +1582,13 @@ static int finish_reply(struct fsg_dev *fsg) /* We have processed all we want from the data the host has sent. * There may still be outstanding bulk-out requests. */ case DATA_DIR_FROM_HOST: - if (fsg->residue == 0) - ; // Nothing to receive + if (fsg->residue == 0) { + /* Nothing to receive */ /* Did the host stop sending unexpectedly early? */ - else if (fsg->short_packet_received) { + } else if (fsg->short_packet_received) { raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); rc = -EINTR; - } /* We haven't processed all the incoming data. Even though * we may be allowed to stall, doing so would cause a race. @@ -1538,17 +1597,17 @@ static int finish_reply(struct fsg_dev *fsg) * STALL. Not realizing the endpoint was halted, it wouldn't * clear the halt -- leading to problems later on. */ #if 0 - else if (fsg->can_stall) { + } else if (fsg->can_stall) { fsg_set_halt(fsg, fsg->bulk_out); raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); rc = -EINTR; - } #endif /* We can't stall. Read in the excess data and throw it * all away. */ - else + } else { rc = throw_away_data(fsg); + } break; } return rc; @@ -1593,7 +1652,7 @@ static int send_status(struct fsg_dev *fsg) } /* Store and send the Bulk-only CSW */ - csw = (void*)bh->buf; + csw = (void *)bh->buf; csw->Signature = cpu_to_le32(USB_BULK_CS_SIG); csw->Tag = fsg->tag; @@ -1629,18 +1688,18 @@ static int check_command(struct fsg_dev *fsg, int cmnd_size, sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir], fsg->data_size); VDBG(fsg, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n", - name, cmnd_size, dirletter[(int) data_dir], - fsg->data_size_from_cmnd, fsg->common->cmnd_size, hdlen); + name, cmnd_size, dirletter[(int) data_dir], + fsg->data_size_from_cmnd, fsg->common->cmnd_size, hdlen); /* We can't reply at all until we know the correct data direction * and size. */ if (fsg->data_size_from_cmnd == 0) data_dir = DATA_DIR_NONE; - if (fsg->data_dir == DATA_DIR_UNKNOWN) { // CB or CBI + if (fsg->data_dir == DATA_DIR_UNKNOWN) { /* CB or CBI */ fsg->data_dir = data_dir; fsg->data_size = fsg->data_size_from_cmnd; - } else { // Bulk-only + } else { /* Bulk-only */ if (fsg->data_size < fsg->data_size_from_cmnd) { /* Host data size < Device data size is a phase error. @@ -1691,7 +1750,8 @@ static int check_command(struct fsg_dev *fsg, int cmnd_size, /* Check the LUN */ if (fsg->common->lun >= 0 && fsg->common->lun < fsg->common->nluns) { - fsg->common->curlun = curlun = &fsg->common->luns[fsg->common->lun]; + curlun = &fsg->common->luns[fsg->common->lun]; + fsg->common->curlun = curlun; if (fsg->common->cmnd[0] != SC_REQUEST_SENSE) { curlun->sense_data = SS_NO_SENSE; curlun->sense_data_info = 0; @@ -1721,7 +1781,7 @@ static int check_command(struct fsg_dev *fsg, int cmnd_size, } /* Check that only command bytes listed in the mask are non-zero */ - fsg->common->cmnd[1] &= 0x1f; // Mask away the LUN + fsg->common->cmnd[1] &= 0x1f; /* Mask away the LUN */ for (i = 1; i < cmnd_size; ++i) { if (fsg->common->cmnd[i] && !(mask & (1 << i))) { if (curlun) @@ -1752,7 +1812,8 @@ static int do_scsi_command(struct fsg_dev *fsg) dump_cdb(fsg->common); /* Wait for the next buffer to become available for data or status */ - bh = fsg->common->next_buffhd_to_drain = fsg->common->next_buffhd_to_fill; + bh = fsg->common->next_buffhd_to_fill; + fsg->common->next_buffhd_to_drain = bh; while (bh->state != BUF_STATE_EMPTY) { rc = sleep_thread(fsg); if (rc) @@ -1761,141 +1822,163 @@ static int do_scsi_command(struct fsg_dev *fsg) fsg->phase_error = 0; fsg->short_packet_received = 0; - down_read(&fsg->common->filesem); // We're using the backing file + /* We're using the backing file */ + down_read(&fsg->common->filesem); switch (fsg->common->cmnd[0]) { case SC_INQUIRY: fsg->data_size_from_cmnd = fsg->common->cmnd[4]; - if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, - (1<<4), 0, - "INQUIRY")) == 0) + reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (1<<4), 0, + "INQUIRY"); + if (reply == 0) reply = do_inquiry(fsg, bh); break; case SC_MODE_SELECT_6: fsg->data_size_from_cmnd = fsg->common->cmnd[4]; - if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, - (1<<1) | (1<<4), 0, - "MODE SELECT(6)")) == 0) + reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, + (1<<1) | (1<<4), 0, + "MODE SELECT(6)"); + if (reply == 0) reply = do_mode_select(fsg, bh); break; case SC_MODE_SELECT_10: - fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->common->cmnd[7]); - if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, - (1<<1) | (3<<7), 0, - "MODE SELECT(10)")) == 0) + fsg->data_size_from_cmnd = + get_unaligned_be16(&fsg->common->cmnd[7]); + reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, + (1<<1) | (3<<7), 0, + "MODE SELECT(10)"); + if (reply == 0) reply = do_mode_select(fsg, bh); break; case SC_MODE_SENSE_6: fsg->data_size_from_cmnd = fsg->common->cmnd[4]; - if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, - (1<<1) | (1<<2) | (1<<4), 0, - "MODE SENSE(6)")) == 0) + reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (1<<1) | (1<<2) | (1<<4), 0, + "MODE SENSE(6)"); + if (reply == 0) reply = do_mode_sense(fsg, bh); break; case SC_MODE_SENSE_10: - fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->common->cmnd[7]); - if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, - (1<<1) | (1<<2) | (3<<7), 0, - "MODE SENSE(10)")) == 0) + fsg->data_size_from_cmnd = + get_unaligned_be16(&fsg->common->cmnd[7]); + reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (1<<1) | (1<<2) | (3<<7), 0, + "MODE SENSE(10)"); + if (reply == 0) reply = do_mode_sense(fsg, bh); break; case SC_PREVENT_ALLOW_MEDIUM_REMOVAL: fsg->data_size_from_cmnd = 0; - if ((reply = check_command(fsg, 6, DATA_DIR_NONE, - (1<<4), 0, - "PREVENT-ALLOW MEDIUM REMOVAL")) == 0) + reply = check_command(fsg, 6, DATA_DIR_NONE, + (1<<4), 0, + "PREVENT-ALLOW MEDIUM REMOVAL"); + if (reply == 0) reply = do_prevent_allow(fsg); break; case SC_READ_6: i = fsg->common->cmnd[4]; fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9; - if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, - (7<<1) | (1<<4), 1, - "READ(6)")) == 0) + reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (7<<1) | (1<<4), 1, + "READ(6)"); + if (reply == 0) reply = do_read(fsg); break; case SC_READ_10: fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->common->cmnd[7]) << 9; - if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, - (1<<1) | (0xf<<2) | (3<<7), 1, - "READ(10)")) == 0) + reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "READ(10)"); + if (reply == 0) reply = do_read(fsg); break; case SC_READ_12: fsg->data_size_from_cmnd = get_unaligned_be32(&fsg->common->cmnd[6]) << 9; - if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST, - (1<<1) | (0xf<<2) | (0xf<<6), 1, - "READ(12)")) == 0) + reply = check_command(fsg, 12, DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (0xf<<6), 1, + "READ(12)"); + if (reply == 0) reply = do_read(fsg); break; case SC_READ_CAPACITY: fsg->data_size_from_cmnd = 8; - if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, - (0xf<<2) | (1<<8), 1, - "READ CAPACITY")) == 0) + reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (0xf<<2) | (1<<8), 1, + "READ CAPACITY"); + if (reply == 0) reply = do_read_capacity(fsg, bh); break; case SC_READ_HEADER: if (!fsg->common->curlun || !fsg->common->curlun->cdrom) goto unknown_cmnd; - fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->common->cmnd[7]); - if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, - (3<<7) | (0x1f<<1), 1, - "READ HEADER")) == 0) + fsg->data_size_from_cmnd = + get_unaligned_be16(&fsg->common->cmnd[7]); + reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (3<<7) | (0x1f<<1), 1, + "READ HEADER"); + if (reply == 0) reply = do_read_header(fsg, bh); break; case SC_READ_TOC: if (!fsg->common->curlun || !fsg->common->curlun->cdrom) goto unknown_cmnd; - fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->common->cmnd[7]); - if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, - (7<<6) | (1<<1), 1, - "READ TOC")) == 0) + fsg->data_size_from_cmnd = + get_unaligned_be16(&fsg->common->cmnd[7]); + reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (7<<6) | (1<<1), 1, + "READ TOC"); + if (reply == 0) reply = do_read_toc(fsg, bh); break; case SC_READ_FORMAT_CAPACITIES: - fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->common->cmnd[7]); - if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, - (3<<7), 1, - "READ FORMAT CAPACITIES")) == 0) + fsg->data_size_from_cmnd = + get_unaligned_be16(&fsg->common->cmnd[7]); + reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (3<<7), 1, + "READ FORMAT CAPACITIES"); + if (reply == 0) reply = do_read_format_capacities(fsg, bh); break; case SC_REQUEST_SENSE: fsg->data_size_from_cmnd = fsg->common->cmnd[4]; - if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, - (1<<4), 0, - "REQUEST SENSE")) == 0) + reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (1<<4), 0, + "REQUEST SENSE"); + if (reply == 0) reply = do_request_sense(fsg, bh); break; case SC_START_STOP_UNIT: fsg->data_size_from_cmnd = 0; - if ((reply = check_command(fsg, 6, DATA_DIR_NONE, - (1<<1) | (1<<4), 0, - "START-STOP UNIT")) == 0) + reply = check_command(fsg, 6, DATA_DIR_NONE, + (1<<1) | (1<<4), 0, + "START-STOP UNIT"); + if (reply == 0) reply = do_start_stop(fsg); break; case SC_SYNCHRONIZE_CACHE: fsg->data_size_from_cmnd = 0; - if ((reply = check_command(fsg, 10, DATA_DIR_NONE, - (0xf<<2) | (3<<7), 1, - "SYNCHRONIZE CACHE")) == 0) + reply = check_command(fsg, 10, DATA_DIR_NONE, + (0xf<<2) | (3<<7), 1, + "SYNCHRONIZE CACHE"); + if (reply == 0) reply = do_synchronize_cache(fsg); break; @@ -1910,36 +1993,40 @@ static int do_scsi_command(struct fsg_dev *fsg) * support a minimal version: BytChk must be 0. */ case SC_VERIFY: fsg->data_size_from_cmnd = 0; - if ((reply = check_command(fsg, 10, DATA_DIR_NONE, - (1<<1) | (0xf<<2) | (3<<7), 1, - "VERIFY")) == 0) + reply = check_command(fsg, 10, DATA_DIR_NONE, + (1<<1) | (0xf<<2) | (3<<7), 1, + "VERIFY"); + if (reply == 0) reply = do_verify(fsg); break; case SC_WRITE_6: i = fsg->common->cmnd[4]; fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9; - if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, - (7<<1) | (1<<4), 1, - "WRITE(6)")) == 0) + reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, + (7<<1) | (1<<4), 1, + "WRITE(6)"); + if (reply == 0) reply = do_write(fsg); break; case SC_WRITE_10: fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->common->cmnd[7]) << 9; - if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, - (1<<1) | (0xf<<2) | (3<<7), 1, - "WRITE(10)")) == 0) + reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "WRITE(10)"); + if (reply == 0) reply = do_write(fsg); break; case SC_WRITE_12: fsg->data_size_from_cmnd = get_unaligned_be32(&fsg->common->cmnd[6]) << 9; - if ((reply = check_command(fsg, 12, DATA_DIR_FROM_HOST, - (1<<1) | (0xf<<2) | (0xf<<6), 1, - "WRITE(12)")) == 0) + reply = check_command(fsg, 12, DATA_DIR_FROM_HOST, + (1<<1) | (0xf<<2) | (0xf<<6), 1, + "WRITE(12)"); + if (reply == 0) reply = do_write(fsg); break; @@ -1951,14 +2038,15 @@ static int do_scsi_command(struct fsg_dev *fsg) case SC_RELEASE: case SC_RESERVE: case SC_SEND_DIAGNOSTIC: - // Fall through + /* Fall through */ default: - unknown_cmnd: +unknown_cmnd: fsg->data_size_from_cmnd = 0; sprintf(unknown, "Unknown x%02x", fsg->common->cmnd[0]); - if ((reply = check_command(fsg, fsg->common->cmnd_size, - DATA_DIR_UNKNOWN, 0xff, 0, unknown)) == 0) { + reply = check_command(fsg, fsg->common->cmnd_size, + DATA_DIR_UNKNOWN, 0xff, 0, unknown); + if (reply == 0) { fsg->common->curlun->sense_data = SS_INVALID_COMMAND; reply = -EINVAL; } @@ -1971,13 +2059,13 @@ static int do_scsi_command(struct fsg_dev *fsg) /* Set up the single reply buffer for finish_reply() */ if (reply == -EINVAL) - reply = 0; // Error reply length + reply = 0; /* Error reply length */ if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) { reply = min((u32) reply, fsg->data_size_from_cmnd); bh->inreq->length = reply; bh->state = BUF_STATE_FULL; fsg->residue -= reply; - } // Otherwise it's already set + } /* Otherwise it's already set */ return 0; } @@ -2157,13 +2245,15 @@ reset: /* Enable the endpoints */ d = fsg_ep_desc(fsg->gadget, &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc); - if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0) + rc = enable_endpoint(fsg, fsg->bulk_in, d); + if (rc != 0) goto reset; fsg->bulk_in_enabled = 1; d = fsg_ep_desc(fsg->gadget, &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc); - if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0) + rc = enable_endpoint(fsg, fsg->bulk_out, d); + if (rc != 0) goto reset; fsg->bulk_out_enabled = 1; fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize); @@ -2173,9 +2263,11 @@ reset: for (i = 0; i < FSG_NUM_BUFFERS; ++i) { struct fsg_buffhd *bh = &fsg->common->buffhds[i]; - if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0) + rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq); + if (rc != 0) goto reset; - if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0) + rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq); + if (rc != 0) goto reset; bh->inreq->buf = bh->outreq->buf = bh->buf; bh->inreq->context = bh->outreq->context = bh; @@ -2302,9 +2394,8 @@ static void handle_exception(struct fsg_dev *fsg) bh = &fsg->common->buffhds[i]; bh->state = BUF_STATE_EMPTY; } - fsg->common->next_buffhd_to_fill = fsg->common->next_buffhd_to_drain = - &fsg->common->buffhds[0]; - + fsg->common->next_buffhd_to_fill = &fsg->common->buffhds[0]; + fsg->common->next_buffhd_to_drain = &fsg->common->buffhds[0]; exception_req_tag = fsg->exception_req_tag; new_config = fsg->new_config; old_state = fsg->state; @@ -2315,8 +2406,8 @@ static void handle_exception(struct fsg_dev *fsg) for (i = 0; i < fsg->common->nluns; ++i) { curlun = &fsg->common->luns[i]; curlun->prevent_medium_removal = 0; - curlun->sense_data = curlun->unit_attention_data = - SS_NO_SENSE; + curlun->sense_data = SS_NO_SENSE; + curlun->unit_attention_data = SS_NO_SENSE; curlun->sense_data_info = 0; curlun->info_valid = 0; } @@ -2342,30 +2433,31 @@ static void handle_exception(struct fsg_dev *fsg) usb_ep_clear_halt(fsg->bulk_in); if (fsg->ep0_req_tag == exception_req_tag) - ep0_queue(fsg); // Complete the status stage + ep0_queue(fsg); /* Complete the status stage */ /* Technically this should go here, but it would only be * a waste of time. Ditto for the INTERFACE_CHANGE and * CONFIG_CHANGE cases. */ - // for (i = 0; i < fsg->common->nluns; ++i) - // fsg->common->luns[i].unit_attention_data = SS_RESET_OCCURRED; + /* for (i = 0; i < fsg->common->nluns; ++i) */ + /* fsg->common->luns[i].unit_attention_data = */ + /* SS_RESET_OCCURRED; */ break; case FSG_STATE_CONFIG_CHANGE: rc = do_set_config(fsg, new_config); if (fsg->ep0_req_tag != exception_req_tag) break; - if (rc != 0) // STALL on errors + if (rc != 0) /* STALL on errors */ fsg_set_halt(fsg, fsg->ep0); - else // Complete the status stage + else /* Complete the status stage */ ep0_queue(fsg); break; case FSG_STATE_EXIT: case FSG_STATE_TERMINATED: - do_set_config(fsg, 0); // Free resources + do_set_config(fsg, 0); /* Free resources */ spin_lock_irq(&fsg->lock); - fsg->state = FSG_STATE_TERMINATED; // Stop the thread + fsg->state = FSG_STATE_TERMINATED; /* Stop the thread */ spin_unlock_irq(&fsg->lock); break; @@ -2645,7 +2737,8 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common, error_luns: common->nluns = i + 1; error_release: - /* Call fsg_common_release() directly, ref is not initialised */ + /* Call fsg_common_release() directly, ref might be not + * initialised */ fsg_common_release(&common->ref); return ERR_PTR(rc); } @@ -2721,13 +2814,13 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f) ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc); if (!ep) goto autoconf_fail; - ep->driver_data = fsg; // claim the endpoint + ep->driver_data = fsg; /* claim the endpoint */ fsg->bulk_in = ep; ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc); if (!ep) goto autoconf_fail; - ep->driver_data = fsg; // claim the endpoint + ep->driver_data = fsg; /* claim the endpoint */ fsg->bulk_out = ep; if (gadget_is_dualspeed(gadget)) { @@ -2770,7 +2863,7 @@ autoconf_fail: rc = -ENOTSUPP; out: - fsg->state = FSG_STATE_TERMINATED; // The thread is dead + fsg->state = FSG_STATE_TERMINATED; /* The thread is dead */ fsg_unbind(c, f); complete(&fsg->thread_notifier); return rc; @@ -2874,18 +2967,16 @@ fsg_config_from_params(struct fsg_config *cfg, const struct fsg_module_parameters *params) { struct fsg_lun_config *lun; - unsigned i, nluns; + unsigned i; /* Configure LUNs */ - nluns = cfg->nluns = !params->luns - ? params->file_count ? params->file_count : 1 - : params->luns; - for (i = 0, lun = cfg->luns; - i < FSG_MAX_LUNS && i < nluns; - ++i, ++lun) { + cfg->nluns = + min(params->luns ?: (params->file_count ?: 1u), + (unsigned)FSG_MAX_LUNS); + for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) { lun->ro = !!params->ro[i]; lun->cdrom = !!params->cdrom[i]; - lun->removable = + lun->removable = /* Removable by default */ params->removable_count <= i || params->removable[i]; lun->filename = params->file_count > i && params->file[i][0] @@ -2893,7 +2984,7 @@ fsg_config_from_params(struct fsg_config *cfg, : 0; } - /* Let FSG use defaults */ + /* Let MSF use defaults */ cfg->lun_name_format = 0; cfg->thread_name = 0; cfg->vendor_name = 0; |