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file_storage.c
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/*
* file_storage.c -- File-backed USB Storage Gadget, for USB development
*
* Copyright (C) 2003-2008 Alan Stern
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The names of the above-listed copyright holders may not be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* ALTERNATIVELY, this software may be distributed under the terms of the
* GNU General Public License ("GPL") as published by the Free Software
* Foundation, either version 2 of that License or (at your option) any
* later version.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* 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.
*
* 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.
*
* The gadget supports the Control-Bulk (CB), Control-Bulk-Interrupt (CBI),
* and Bulk-Only (also known as Bulk-Bulk-Bulk or BBB) transports, selected
* by the optional "transport" module parameter. It also supports the
* following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03),
* UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by
* the optional "protocol" module parameter. In addition, the default
* Vendor ID, Product ID, and release number can be overridden.
*
* 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.
*
* 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
* interrupt-in endpoints. With most device controllers this isn't an
* 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
* transport=XXX Default BBB, transport name (CB, CBI, or BBB)
* protocol=YYY Default SCSI, protocol name (RBC, 8020 or
* ATAPI, QIC, UFI, 8070, or SCSI;
* also 1 - 6)
* vendor=0xVVVV Default 0x0525 (NetChip), USB Vendor ID
* product=0xPPPP Default 0xa4a5 (FSG), USB Product ID
* release=0xRRRR Override the USB release number (bcdDevice)
* buflen=N Default N=16384, buffer size used (will be
* rounded down to a multiple of
* PAGE_CACHE_SIZE)
*
* If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "ro",
* "removable", "luns", "stall", and "cdrom" options are available; default
* values are used for everything else.
*
* 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
* <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
*/
/*
* Driver Design
*
* The FSG driver 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.
* Completion events are passed to the main thread by wakeup calls. Many
* ep0 requests are handled at interrupt time, but SetInterface,
* SetConfiguration, and device reset requests are forwarded to the
* thread in the form of "exceptions" using SIGUSR1 signals (since they
* should interrupt any ongoing file I/O operations).
*
* The thread's main routine implements the standard command/data/status
* parts of a SCSI interaction. It and its subroutines are full of tests
* for pending signals/exceptions -- all this polling is necessary since
* the kernel has no setjmp/longjmp equivalents. (Maybe this is an
* indication that the driver really wants to be running in userspace.)
* An important point is that so long as the thread is alive it keeps an
* open reference to the backing file. This will prevent unmounting
* the backing file's underlying filesystem and could cause problems
* during system shutdown, for example. To prevent such problems, the
* thread catches INT, TERM, and KILL signals and converts them into
* 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.
*
* To provide maximum throughput, the driver uses a circular pipeline of
* buffer heads (struct fsg_buffhd). In principle the pipeline can be
* arbitrarily long; in practice the benefits don't justify having more
* than 2 stages (i.e., double buffering). But it helps to think of the
* pipeline as being a long one. Each buffer head contains a bulk-in and
* a bulk-out request pointer (since the buffer can be used for both
* output and input -- directions always are given from the host's
* point of view) as well as a pointer to the buffer and various state
* variables.
*
* Use of the pipeline follows a simple protocol. There is a variable
* (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
* At any time that buffer head may still be in use from an earlier
* request, so each buffer head has a state variable indicating whether
* it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
* buffer head to be EMPTY, filling the buffer either by file I/O or by
* USB I/O (during which the buffer head is BUSY), and marking the buffer
* head FULL when the I/O is complete. Then the buffer will be emptied
* (again possibly by USB I/O, during which it is marked BUSY) and
* finally marked EMPTY again (possibly by a completion routine).
*
* A module parameter tells the driver to avoid stalling the bulk
* endpoints wherever the transport specification allows. This is
* necessary for some UDCs like the SuperH, which cannot reliably clear a
* halt on a bulk endpoint. However, under certain circumstances the
* Bulk-only specification requires a stall. In such cases the driver
* will halt the endpoint and set a flag indicating that it should clear
* the halt in software during the next device reset. Hopefully this
* will permit everything to work correctly. Furthermore, although the
* specification allows the bulk-out endpoint to halt when the host sends
* too much data, implementing this would cause an unavoidable race.
* The driver will always use the "no-stall" approach for OUT transfers.
*
* One subtle point concerns sending status-stage responses for ep0
* requests. Some of these requests, such as device reset, can involve
* interrupting an ongoing file I/O operation, which might take an
* arbitrarily long time. During that delay the host might give up on
* the original ep0 request and issue a new one. When that happens the
* driver should not notify the host about completion of the original
* request, as the host will no longer be waiting for it. So the driver
* assigns to each ep0 request a unique tag, and it keeps track of the
* tag value of the request associated with a long-running exception
* (device-reset, interface-change, or configuration-change). When the
* exception handler is finished, the status-stage response is submitted
* only if the current ep0 request tag is equal to the exception request
* tag. Thus only the most recently received ep0 request will get a
* status-stage response.
*
* Warning: This driver source file is too long. It ought to be split up
* into a header file plus about 3 separate .c files, to handle the details
* of the Gadget, USB Mass Storage, and SCSI protocols.
*/
/* #define VERBOSE_DEBUG */
/* #define DUMP_MSGS */
#include <linux/blkdev.h>
#include <linux/completion.h>
#include <linux/dcache.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/fcntl.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/kref.h>
#include <linux/kthread.h>
#include <linux/limits.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/freezer.h>
#include <linux/utsname.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include "gadget_chips.h"
/*
* Kbuild is not very cooperative with respect to linking separately
* compiled library objects into one module. So for now we won't use
* separate compilation ... ensuring init/exit sections work to shrink
* the runtime footprint, and giving us at least some parts of what
* a "gcc --combine ... part1.c part2.c part3.c ... " build would.
*/
#include "usbstring.c"
#include "config.c"
#include "epautoconf.c"
/*-------------------------------------------------------------------------*/
#define DRIVER_DESC "File-backed Storage Gadget"
#define DRIVER_NAME "g_file_storage"
#define DRIVER_VERSION "20 November 2008"
static char fsg_string_manufacturer[64];
static const char fsg_string_product[] = DRIVER_DESC;
static char fsg_string_serial[13];
static const char fsg_string_config[] = "Self-powered";
static const char fsg_string_interface[] = "Mass Storage";
#include "storage_common.c"
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Alan Stern");
MODULE_LICENSE("Dual BSD/GPL");
/*
* This driver assumes self-powered hardware and has no way for users to
* trigger remote wakeup. It uses autoconfiguration to select endpoints
* and endpoint addresses.
*/
/*-------------------------------------------------------------------------*/
/* Encapsulate the module parameter settings */
static struct {
char *file[FSG_MAX_LUNS];
int ro[FSG_MAX_LUNS];
unsigned int num_filenames;
unsigned int num_ros;
unsigned int nluns;
int removable;
int can_stall;
int cdrom;
char *transport_parm;
char *protocol_parm;
unsigned short vendor;
unsigned short product;
unsigned short release;
unsigned int buflen;
int transport_type;
char *transport_name;
int protocol_type;
char *protocol_name;
} mod_data = { // Default values
.transport_parm = "BBB",
.protocol_parm = "SCSI",
#ifdef CONFIG_MXS_VBUS_CURRENT_DRAW
.removable = 1,
#else
.removable = 0,
#endif
.can_stall = 1,
.cdrom = 0,
.vendor = FSG_VENDOR_ID,
.product = FSG_PRODUCT_ID,
.release = 0xffff, // Use controller chip type
.buflen = 16384,
};
module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames,
S_IRUGO);
MODULE_PARM_DESC(file, "names of backing files or devices");
module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO);
MODULE_PARM_DESC(ro, "true to force read-only");
module_param_named(luns, mod_data.nluns, uint, S_IRUGO);
MODULE_PARM_DESC(luns, "number of LUNs");
module_param_named(removable, mod_data.removable, bool, S_IRUGO);
MODULE_PARM_DESC(removable, "true to simulate removable media");
module_param_named(stall, mod_data.can_stall, bool, S_IRUGO);
MODULE_PARM_DESC(stall, "false to prevent bulk stalls");
module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO);
MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk");
/* In the non-TEST version, only the module parameters listed above
* are available. */
#ifdef CONFIG_USB_FILE_STORAGE_TEST
module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO);
MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)");
module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO);
MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, "
"8070, or SCSI)");
module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO);
MODULE_PARM_DESC(vendor, "USB Vendor ID");
module_param_named(product, mod_data.product, ushort, S_IRUGO);
MODULE_PARM_DESC(product, "USB Product ID");
module_param_named(release, mod_data.release, ushort, S_IRUGO);
MODULE_PARM_DESC(release, "USB release number");
module_param_named(buflen, mod_data.buflen, uint, S_IRUGO);
MODULE_PARM_DESC(buflen, "I/O buffer size");
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
/*
* These definitions will permit the compiler to avoid generating code for
* parts of the driver that aren't used in the non-TEST version. Even gcc
* can recognize when a test of a constant expression yields a dead code
* path.
*/
#ifdef CONFIG_USB_FILE_STORAGE_TEST
#define transport_is_bbb() (mod_data.transport_type == USB_PR_BULK)
#define transport_is_cbi() (mod_data.transport_type == USB_PR_CBI)
#define protocol_is_scsi() (mod_data.protocol_type == USB_SC_SCSI)
#else
#define transport_is_bbb() 1
#define transport_is_cbi() 0
#define protocol_is_scsi() 1
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
/*-------------------------------------------------------------------------*/
struct fsg_dev {
/* lock protects: state, all the req_busy's, and cbbuf_cmnd */
spinlock_t lock;
struct usb_gadget *gadget;
/* filesem protects: backing files in use */
struct rw_semaphore filesem;
/* reference counting: wait until all LUNs are released */
struct kref ref;
struct usb_ep *ep0; // Handy copy of gadget->ep0
struct usb_request *ep0req; // For control responses
unsigned int ep0_req_tag;
const char *ep0req_name;
struct usb_request *intreq; // For interrupt responses
int intreq_busy;
struct fsg_buffhd *intr_buffhd;
unsigned int bulk_out_maxpacket;
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 intr_in_enabled : 1;
unsigned int phase_error : 1;
unsigned int short_packet_received : 1;
unsigned int bad_lun_okay : 1;
unsigned long atomic_bitflags;
#define REGISTERED 0
#define IGNORE_BULK_OUT 1
#define SUSPENDED 2
struct usb_ep *bulk_in;
struct usb_ep *bulk_out;
struct usb_ep *intr_in;
struct fsg_buffhd *next_buffhd_to_fill;
struct fsg_buffhd *next_buffhd_to_drain;
struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
int thread_wakeup_needed;
struct completion thread_notifier;
struct task_struct *thread_task;
int cmnd_size;
u8 cmnd[MAX_COMMAND_SIZE];
enum data_direction data_dir;
u32 data_size;
u32 data_size_from_cmnd;
u32 tag;
unsigned int lun;
u32 residue;
u32 usb_amount_left;
/* The CB protocol offers no way for a host to know when a command
* has completed. As a result the next command may arrive early,
* and we will still have to handle it. For that reason we need
* a buffer to store new commands when using CB (or CBI, which
* does not oblige a host to wait for command completion either). */
int cbbuf_cmnd_size;
u8 cbbuf_cmnd[MAX_COMMAND_SIZE];
unsigned int nluns;
struct fsg_lun *luns;
struct fsg_lun *curlun;
#ifdef CONFIG_FSL_UTP
void *utp;
#endif
};
#ifdef CONFIG_FSL_UTP
#include "fsl_updater.h"
#endif
static int do_set_interface(struct fsg_dev *fsg, int altsetting);
typedef void (*fsg_routine_t)(struct fsg_dev *);
static int exception_in_progress(struct fsg_dev *fsg)
{
return (fsg->state > FSG_STATE_IDLE);
}
/* Make bulk-out requests be divisible by the maxpacket size */
static void set_bulk_out_req_length(struct fsg_dev *fsg,
struct fsg_buffhd *bh, unsigned int length)
{
unsigned int rem;
bh->bulk_out_intended_length = length;
rem = length % fsg->bulk_out_maxpacket;
if (rem > 0)
length += fsg->bulk_out_maxpacket - rem;
bh->outreq->length = length;
}
static struct fsg_dev *the_fsg;
static struct usb_gadget_driver fsg_driver;
/*-------------------------------------------------------------------------*/
static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
{
const char *name;
if (ep == fsg->bulk_in)
name = "bulk-in";
else if (ep == fsg->bulk_out)
name = "bulk-out";
else
name = ep->name;
DBG(fsg, "%s set halt\n", name);
return usb_ep_set_halt(ep);
}
/*-------------------------------------------------------------------------*/
/*
* DESCRIPTORS ... most are static, but strings and (full) configuration
* descriptors are built on demand. Also the (static) config and interface
* descriptors are adjusted during fsg_bind().
*/
/* There is only one configuration. */
#define CONFIG_VALUE 1
static struct usb_device_descriptor
device_desc = {
.bLength = sizeof device_desc,
.bDescriptorType = USB_DT_DEVICE,
.bcdUSB = cpu_to_le16(0x0200),
.bDeviceClass = USB_CLASS_PER_INTERFACE,
/* The next three values can be overridden by module parameters */
.idVendor = cpu_to_le16(FSG_VENDOR_ID),
.idProduct = cpu_to_le16(FSG_PRODUCT_ID),
.bcdDevice = cpu_to_le16(0xffff),
.iManufacturer = FSG_STRING_MANUFACTURER,
.iProduct = FSG_STRING_PRODUCT,
#ifdef CONFIG_FSL_UTP
.iSerialNumber = 0,
#else
.iSerialNumber = FSG_STRING_SERIAL,
#endif
.bNumConfigurations = 1,
};
static struct usb_config_descriptor
config_desc = {
.bLength = sizeof config_desc,
.bDescriptorType = USB_DT_CONFIG,
/* wTotalLength computed by usb_gadget_config_buf() */
.bNumInterfaces = 1,
.bConfigurationValue = CONFIG_VALUE,
.iConfiguration = FSG_STRING_CONFIG,
.bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
.bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2,
};
static struct usb_qualifier_descriptor
dev_qualifier = {
.bLength = sizeof dev_qualifier,
.bDescriptorType = USB_DT_DEVICE_QUALIFIER,
.bcdUSB = cpu_to_le16(0x0200),
.bDeviceClass = USB_CLASS_PER_INTERFACE,
.bNumConfigurations = 1,
};
/*
* Config descriptors must agree with the code that sets configurations
* and with code managing interfaces and their altsettings. They must
* also handle different speeds and other-speed requests.
*/
static int populate_config_buf(struct usb_gadget *gadget,
u8 *buf, u8 type, unsigned index)
{
enum usb_device_speed speed = gadget->speed;
int len;
const struct usb_descriptor_header **function;
if (index > 0)
return -EINVAL;
if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG)
speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed;
function = gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH
? (const struct usb_descriptor_header **)fsg_hs_function
: (const struct usb_descriptor_header **)fsg_fs_function;
/* for now, don't advertise srp-only devices */
if (!gadget_is_otg(gadget))
function++;
len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function);
((struct usb_config_descriptor *) buf)->bDescriptorType = type;
return len;
}
/*-------------------------------------------------------------------------*/
/* These routines may be called in process context or in_irq */
/* Caller must hold fsg->lock */
static void wakeup_thread(struct fsg_dev *fsg)
{
/* Tell the main thread that something has happened */
fsg->thread_wakeup_needed = 1;
if (fsg->thread_task)
wake_up_process(fsg->thread_task);
}
static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
{
unsigned long flags;
/* Do nothing if a higher-priority exception is already in progress.
* If a lower-or-equal priority exception is in progress, preempt it
* and notify the main thread by sending it a signal. */
spin_lock_irqsave(&fsg->lock, flags);
if (fsg->state <= new_state) {
fsg->exception_req_tag = fsg->ep0_req_tag;
fsg->state = new_state;
if (fsg->thread_task)
send_sig_info(SIGUSR1, SEND_SIG_FORCED,
fsg->thread_task);
}
spin_unlock_irqrestore(&fsg->lock, flags);
}
/*-------------------------------------------------------------------------*/
/* The disconnect callback and ep0 routines. These always run in_irq,
* except that ep0_queue() is called in the main thread to acknowledge
* completion of various requests: set config, set interface, and
* Bulk-only device reset. */
static void fsg_disconnect(struct usb_gadget *gadget)
{
struct fsg_dev *fsg = get_gadget_data(gadget);
DBG(fsg, "disconnect or port reset\n");
/*
* The disconnect exception will call do_set_config, and therefore will
* visit controller registers. However it is a delayed event, and will be
* handled at another process, so the controller maybe have already closed the
* usb clock.
*/
if (fsg->new_config)
do_set_interface(fsg, -1);/* disable the interface */
raise_exception(fsg, FSG_STATE_DISCONNECT);
}
static int ep0_queue(struct fsg_dev *fsg)
{
int rc;
rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
if (rc != 0 && rc != -ESHUTDOWN) {
/* We can't do much more than wait for a reset */
WARNING(fsg, "error in submission: %s --> %d\n",
fsg->ep0->name, rc);
}
return rc;
}
static void ep0_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
if (req->actual > 0)
dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual);
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
usb_ep_fifo_flush(ep);
if (req->status == 0 && req->context)
((fsg_routine_t) (req->context))(fsg);
}
/*-------------------------------------------------------------------------*/
/* Bulk and interrupt endpoint completion handlers.
* These always run in_irq. */
static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
struct fsg_buffhd *bh = req->context;
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
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
smp_wmb();
spin_lock(&fsg->lock);
bh->inreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
struct fsg_buffhd *bh = req->context;
dump_msg(fsg, "bulk-out", req->buf, req->actual);
if (req->status || req->actual != bh->bulk_out_intended_length)
DBG(fsg, "%s --> %d, %u/%u\n", __func__,
req->status, req->actual,
bh->bulk_out_intended_length);
if (req->status == -ECONNRESET) // Request was cancelled
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
smp_wmb();
spin_lock(&fsg->lock);
bh->outreq_busy = 0;
bh->state = BUF_STATE_FULL;
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
#ifdef CONFIG_USB_FILE_STORAGE_TEST
static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
struct fsg_buffhd *bh = req->context;
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
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
smp_wmb();
spin_lock(&fsg->lock);
fsg->intreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
#else
static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
{}
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
/*-------------------------------------------------------------------------*/
/* Ep0 class-specific handlers. These always run in_irq. */
#ifdef CONFIG_USB_FILE_STORAGE_TEST
static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct usb_request *req = fsg->ep0req;
static u8 cbi_reset_cmnd[6] = {
SC_SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff};
/* Error in command transfer? */
if (req->status || req->length != req->actual ||
req->actual < 6 || req->actual > MAX_COMMAND_SIZE) {
/* Not all controllers allow a protocol stall after
* receiving control-out data, but we'll try anyway. */
fsg_set_halt(fsg, fsg->ep0);
return; // Wait for reset
}
/* Is it the special reset command? */
if (req->actual >= sizeof cbi_reset_cmnd &&
memcmp(req->buf, cbi_reset_cmnd,
sizeof cbi_reset_cmnd) == 0) {
/* Raise an exception to stop the current operation
* and reinitialize our state. */
DBG(fsg, "cbi reset request\n");
raise_exception(fsg, FSG_STATE_RESET);
return;
}
VDBG(fsg, "CB[I] accept device-specific command\n");
spin_lock(&fsg->lock);
/* Save the command for later */
if (fsg->cbbuf_cmnd_size)
WARNING(fsg, "CB[I] overwriting previous command\n");
fsg->cbbuf_cmnd_size = req->actual;
memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
#else
static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{}
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
static int class_setup_req(struct fsg_dev *fsg,
const struct usb_ctrlrequest *ctrl)
{
struct usb_request *req = fsg->ep0req;
int value = -EOPNOTSUPP;
u16 w_index = le16_to_cpu(ctrl->wIndex);
u16 w_value = le16_to_cpu(ctrl->wValue);
u16 w_length = le16_to_cpu(ctrl->wLength);
if (!fsg->config)
return value;
/* Handle Bulk-only class-specific requests */
if (transport_is_bbb()) {
switch (ctrl->bRequest) {
case USB_BULK_RESET_REQUEST:
if (ctrl->bRequestType != (USB_DIR_OUT |
USB_TYPE_CLASS | USB_RECIP_INTERFACE))
break;
if (w_index != 0 || w_value != 0) {
value = -EDOM;
break;
}
/* Raise an exception to stop the current operation
* and reinitialize our state. */
DBG(fsg, "bulk reset request\n");
raise_exception(fsg, FSG_STATE_RESET);
value = DELAYED_STATUS;
break;
case USB_BULK_GET_MAX_LUN_REQUEST:
if (ctrl->bRequestType != (USB_DIR_IN |
USB_TYPE_CLASS | USB_RECIP_INTERFACE))
break;
if (w_index != 0 || w_value != 0) {
value = -EDOM;
break;
}
VDBG(fsg, "get max LUN\n");
*(u8 *) req->buf = fsg->nluns - 1;
value = 1;
break;
}
}
/* Handle CBI class-specific requests */
else {
switch (ctrl->bRequest) {
case USB_CBI_ADSC_REQUEST:
if (ctrl->bRequestType != (USB_DIR_OUT |
USB_TYPE_CLASS | USB_RECIP_INTERFACE))
break;
if (w_index != 0 || w_value != 0) {
value = -EDOM;
break;
}
if (w_length > MAX_COMMAND_SIZE) {
value = -EOVERFLOW;
break;
}
value = w_length;
fsg->ep0req->context = received_cbi_adsc;
break;
}
}
if (value == -EOPNOTSUPP)
VDBG(fsg,
"unknown class-specific control req "
"%02x.%02x v%04x i%04x l%u\n",
ctrl->bRequestType, ctrl->bRequest,
le16_to_cpu(ctrl->wValue), w_index, w_length);
return value;
}
/*-------------------------------------------------------------------------*/
/* Ep0 standard request handlers. These always run in_irq. */
static int standard_setup_req(struct fsg_dev *fsg,
const struct usb_ctrlrequest *ctrl)
{
struct usb_request *req = fsg->ep0req;
int value = -EOPNOTSUPP;
u16 w_index = le16_to_cpu(ctrl->wIndex);
u16 w_value = le16_to_cpu(ctrl->wValue);
/* Usually this just stores reply data in the pre-allocated ep0 buffer,
* but config change events will also reconfigure hardware. */
switch (ctrl->bRequest) {
case USB_REQ_GET_DESCRIPTOR:
if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
USB_RECIP_DEVICE))
break;
switch (w_value >> 8) {
case USB_DT_DEVICE:
VDBG(fsg, "get device descriptor\n");
value = sizeof device_desc;
memcpy(req->buf, &device_desc, value);
break;
case USB_DT_DEVICE_QUALIFIER:
VDBG(fsg, "get device qualifier\n");
if (!gadget_is_dualspeed(fsg->gadget))
break;
value = sizeof dev_qualifier;
memcpy(req->buf, &dev_qualifier, value);
break;
case USB_DT_OTHER_SPEED_CONFIG:
VDBG(fsg, "get other-speed config descriptor\n");
if (!gadget_is_dualspeed(fsg->gadget))
break;
goto get_config;
case USB_DT_CONFIG:
VDBG(fsg, "get configuration descriptor\n");
get_config:
value = populate_config_buf(fsg->gadget,
req->buf,
w_value >> 8,
w_value & 0xff);
break;
case USB_DT_STRING:
VDBG(fsg, "get string descriptor\n");
/* wIndex == language code */
value = usb_gadget_get_string(&fsg_stringtab,
w_value & 0xff, req->buf);
break;
}
break;
/* One config, two speeds */
case USB_REQ_SET_CONFIGURATION:
if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD |
USB_RECIP_DEVICE))
break;
VDBG(fsg, "set configuration\n");
if (w_value == CONFIG_VALUE || w_value == 0) {
fsg->new_config = w_value;
/* Raise an exception to wipe out previous transaction
* state (queued bufs, etc) and set the new config. */
raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
value = DELAYED_STATUS;
}
break;
case USB_REQ_GET_CONFIGURATION:
if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
USB_RECIP_DEVICE))
break;
VDBG(fsg, "get configuration\n");