304 lines
8.2 KiB
C
304 lines
8.2 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
/*
|
||
|
|
* u_fs.h
|
||
|
|
*
|
||
|
|
* Utility definitions for the FunctionFS
|
||
|
|
*
|
||
|
|
* Copyright (c) 2013 Samsung Electronics Co., Ltd.
|
||
|
|
* http://www.samsung.com
|
||
|
|
*
|
||
|
|
* Author: Andrzej Pietrasiewicz <andrzejtp2010@gmail.com>
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef U_FFS_H
|
||
|
|
#define U_FFS_H
|
||
|
|
|
||
|
|
#include <linux/usb/composite.h>
|
||
|
|
#include <linux/list.h>
|
||
|
|
#include <linux/mutex.h>
|
||
|
|
#include <linux/workqueue.h>
|
||
|
|
#include <linux/refcount.h>
|
||
|
|
|
||
|
|
#ifdef VERBOSE_DEBUG
|
||
|
|
#ifndef pr_vdebug
|
||
|
|
# define pr_vdebug pr_debug
|
||
|
|
#endif /* pr_vdebug */
|
||
|
|
# define ffs_dump_mem(prefix, ptr, len) \
|
||
|
|
print_hex_dump_bytes(pr_fmt(prefix ": "), DUMP_PREFIX_NONE, ptr, len)
|
||
|
|
#else
|
||
|
|
#ifndef pr_vdebug
|
||
|
|
# define pr_vdebug(...) do { } while (0)
|
||
|
|
#endif /* pr_vdebug */
|
||
|
|
# define ffs_dump_mem(prefix, ptr, len) do { } while (0)
|
||
|
|
#endif /* VERBOSE_DEBUG */
|
||
|
|
|
||
|
|
#define ENTER() pr_vdebug("%s()\n", __func__)
|
||
|
|
|
||
|
|
struct f_fs_opts;
|
||
|
|
|
||
|
|
struct ffs_dev {
|
||
|
|
struct ffs_data *ffs_data;
|
||
|
|
struct f_fs_opts *opts;
|
||
|
|
struct list_head entry;
|
||
|
|
|
||
|
|
char name[41];
|
||
|
|
|
||
|
|
bool mounted;
|
||
|
|
bool desc_ready;
|
||
|
|
bool single;
|
||
|
|
|
||
|
|
int (*ffs_ready_callback)(struct ffs_data *ffs);
|
||
|
|
void (*ffs_closed_callback)(struct ffs_data *ffs);
|
||
|
|
void *(*ffs_acquire_dev_callback)(struct ffs_dev *dev);
|
||
|
|
void (*ffs_release_dev_callback)(struct ffs_dev *dev);
|
||
|
|
};
|
||
|
|
|
||
|
|
extern struct mutex ffs_lock;
|
||
|
|
|
||
|
|
static inline void ffs_dev_lock(void)
|
||
|
|
{
|
||
|
|
mutex_lock(&ffs_lock);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void ffs_dev_unlock(void)
|
||
|
|
{
|
||
|
|
mutex_unlock(&ffs_lock);
|
||
|
|
}
|
||
|
|
|
||
|
|
int ffs_name_dev(struct ffs_dev *dev, const char *name);
|
||
|
|
int ffs_single_dev(struct ffs_dev *dev);
|
||
|
|
|
||
|
|
struct ffs_epfile;
|
||
|
|
struct ffs_function;
|
||
|
|
|
||
|
|
enum ffs_state {
|
||
|
|
/*
|
||
|
|
* Waiting for descriptors and strings.
|
||
|
|
*
|
||
|
|
* In this state no open(2), read(2) or write(2) on epfiles
|
||
|
|
* may succeed (which should not be the problem as there
|
||
|
|
* should be no such files opened in the first place).
|
||
|
|
*/
|
||
|
|
FFS_READ_DESCRIPTORS,
|
||
|
|
FFS_READ_STRINGS,
|
||
|
|
|
||
|
|
/*
|
||
|
|
* We've got descriptors and strings. We are or have called
|
||
|
|
* functionfs_ready_callback(). functionfs_bind() may have
|
||
|
|
* been called but we don't know.
|
||
|
|
*
|
||
|
|
* This is the only state in which operations on epfiles may
|
||
|
|
* succeed.
|
||
|
|
*/
|
||
|
|
FFS_ACTIVE,
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Function is visible to host, but it's not functional. All
|
||
|
|
* setup requests are stalled and transfers on another endpoints
|
||
|
|
* are refused. All epfiles, except ep0, are deleted so there
|
||
|
|
* is no way to perform any operations on them.
|
||
|
|
*
|
||
|
|
* This state is set after closing all functionfs files, when
|
||
|
|
* mount parameter "no_disconnect=1" has been set. Function will
|
||
|
|
* remain in deactivated state until filesystem is umounted or
|
||
|
|
* ep0 is opened again. In the second case functionfs state will
|
||
|
|
* be reset, and it will be ready for descriptors and strings
|
||
|
|
* writing.
|
||
|
|
*
|
||
|
|
* This is useful only when functionfs is composed to gadget
|
||
|
|
* with another function which can perform some critical
|
||
|
|
* operations, and it's strongly desired to have this operations
|
||
|
|
* completed, even after functionfs files closure.
|
||
|
|
*/
|
||
|
|
FFS_DEACTIVATED,
|
||
|
|
|
||
|
|
/*
|
||
|
|
* All endpoints have been closed. This state is also set if
|
||
|
|
* we encounter an unrecoverable error. The only
|
||
|
|
* unrecoverable error is situation when after reading strings
|
||
|
|
* from user space we fail to initialise epfiles or
|
||
|
|
* functionfs_ready_callback() returns with error (<0).
|
||
|
|
*
|
||
|
|
* In this state no open(2), read(2) or write(2) (both on ep0
|
||
|
|
* as well as epfile) may succeed (at this point epfiles are
|
||
|
|
* unlinked and all closed so this is not a problem; ep0 is
|
||
|
|
* also closed but ep0 file exists and so open(2) on ep0 must
|
||
|
|
* fail).
|
||
|
|
*/
|
||
|
|
FFS_CLOSING
|
||
|
|
};
|
||
|
|
|
||
|
|
enum ffs_setup_state {
|
||
|
|
/* There is no setup request pending. */
|
||
|
|
FFS_NO_SETUP,
|
||
|
|
/*
|
||
|
|
* User has read events and there was a setup request event
|
||
|
|
* there. The next read/write on ep0 will handle the
|
||
|
|
* request.
|
||
|
|
*/
|
||
|
|
FFS_SETUP_PENDING,
|
||
|
|
/*
|
||
|
|
* There was event pending but before user space handled it
|
||
|
|
* some other event was introduced which canceled existing
|
||
|
|
* setup. If this state is set read/write on ep0 return
|
||
|
|
* -EIDRM. This state is only set when adding event.
|
||
|
|
*/
|
||
|
|
FFS_SETUP_CANCELLED
|
||
|
|
};
|
||
|
|
|
||
|
|
struct ffs_data {
|
||
|
|
struct usb_gadget *gadget;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Protect access read/write operations, only one read/write
|
||
|
|
* at a time. As a consequence protects ep0req and company.
|
||
|
|
* While setup request is being processed (queued) this is
|
||
|
|
* held.
|
||
|
|
*/
|
||
|
|
struct mutex mutex;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Protect access to endpoint related structures (basically
|
||
|
|
* usb_ep_queue(), usb_ep_dequeue(), etc. calls) except for
|
||
|
|
* endpoint zero.
|
||
|
|
*/
|
||
|
|
spinlock_t eps_lock;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* XXX REVISIT do we need our own request? Since we are not
|
||
|
|
* handling setup requests immediately user space may be so
|
||
|
|
* slow that another setup will be sent to the gadget but this
|
||
|
|
* time not to us but another function and then there could be
|
||
|
|
* a race. Is that the case? Or maybe we can use cdev->req
|
||
|
|
* after all, maybe we just need some spinlock for that?
|
||
|
|
*/
|
||
|
|
struct usb_request *ep0req; /* P: mutex */
|
||
|
|
struct completion ep0req_completion; /* P: mutex */
|
||
|
|
|
||
|
|
/* reference counter */
|
||
|
|
refcount_t ref;
|
||
|
|
/* how many files are opened (EP0 and others) */
|
||
|
|
atomic_t opened;
|
||
|
|
|
||
|
|
/* EP0 state */
|
||
|
|
enum ffs_state state;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Possible transitions:
|
||
|
|
* + FFS_NO_SETUP -> FFS_SETUP_PENDING -- P: ev.waitq.lock
|
||
|
|
* happens only in ep0 read which is P: mutex
|
||
|
|
* + FFS_SETUP_PENDING -> FFS_NO_SETUP -- P: ev.waitq.lock
|
||
|
|
* happens only in ep0 i/o which is P: mutex
|
||
|
|
* + FFS_SETUP_PENDING -> FFS_SETUP_CANCELLED -- P: ev.waitq.lock
|
||
|
|
* + FFS_SETUP_CANCELLED -> FFS_NO_SETUP -- cmpxchg
|
||
|
|
*
|
||
|
|
* This field should never be accessed directly and instead
|
||
|
|
* ffs_setup_state_clear_cancelled function should be used.
|
||
|
|
*/
|
||
|
|
enum ffs_setup_state setup_state;
|
||
|
|
|
||
|
|
/* Events & such. */
|
||
|
|
struct {
|
||
|
|
u8 types[4];
|
||
|
|
unsigned short count;
|
||
|
|
/* XXX REVISIT need to update it in some places, or do we? */
|
||
|
|
unsigned short can_stall;
|
||
|
|
struct usb_ctrlrequest setup;
|
||
|
|
|
||
|
|
wait_queue_head_t waitq;
|
||
|
|
} ev; /* the whole structure, P: ev.waitq.lock */
|
||
|
|
|
||
|
|
/* Flags */
|
||
|
|
unsigned long flags;
|
||
|
|
#define FFS_FL_CALL_CLOSED_CALLBACK 0
|
||
|
|
#define FFS_FL_BOUND 1
|
||
|
|
|
||
|
|
/* For waking up blocked threads when function is enabled. */
|
||
|
|
wait_queue_head_t wait;
|
||
|
|
|
||
|
|
/* Active function */
|
||
|
|
struct ffs_function *func;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Device name, write once when file system is mounted.
|
||
|
|
* Intended for user to read if she wants.
|
||
|
|
*/
|
||
|
|
const char *dev_name;
|
||
|
|
/* Private data for our user (ie. gadget). Managed by user. */
|
||
|
|
void *private_data;
|
||
|
|
|
||
|
|
/* filled by __ffs_data_got_descs() */
|
||
|
|
/*
|
||
|
|
* raw_descs is what you kfree, real_descs points inside of raw_descs,
|
||
|
|
* where full speed, high speed and super speed descriptors start.
|
||
|
|
* real_descs_length is the length of all those descriptors.
|
||
|
|
*/
|
||
|
|
const void *raw_descs_data;
|
||
|
|
const void *raw_descs;
|
||
|
|
unsigned raw_descs_length;
|
||
|
|
unsigned fs_descs_count;
|
||
|
|
unsigned hs_descs_count;
|
||
|
|
unsigned ss_descs_count;
|
||
|
|
unsigned ms_os_descs_count;
|
||
|
|
unsigned ms_os_descs_ext_prop_count;
|
||
|
|
unsigned ms_os_descs_ext_prop_name_len;
|
||
|
|
unsigned ms_os_descs_ext_prop_data_len;
|
||
|
|
void *ms_os_descs_ext_prop_avail;
|
||
|
|
void *ms_os_descs_ext_prop_name_avail;
|
||
|
|
void *ms_os_descs_ext_prop_data_avail;
|
||
|
|
|
||
|
|
unsigned user_flags;
|
||
|
|
|
||
|
|
#define FFS_MAX_EPS_COUNT 31
|
||
|
|
u8 eps_addrmap[FFS_MAX_EPS_COUNT];
|
||
|
|
|
||
|
|
unsigned short strings_count;
|
||
|
|
unsigned short interfaces_count;
|
||
|
|
unsigned short eps_count;
|
||
|
|
unsigned short _pad1;
|
||
|
|
|
||
|
|
/* filled by __ffs_data_got_strings() */
|
||
|
|
/* ids in stringtabs are set in functionfs_bind() */
|
||
|
|
const void *raw_strings;
|
||
|
|
struct usb_gadget_strings **stringtabs;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* File system's super block, write once when file system is
|
||
|
|
* mounted.
|
||
|
|
*/
|
||
|
|
struct super_block *sb;
|
||
|
|
|
||
|
|
/* File permissions, written once when fs is mounted */
|
||
|
|
struct ffs_file_perms {
|
||
|
|
umode_t mode;
|
||
|
|
kuid_t uid;
|
||
|
|
kgid_t gid;
|
||
|
|
} file_perms;
|
||
|
|
|
||
|
|
struct eventfd_ctx *ffs_eventfd;
|
||
|
|
struct workqueue_struct *io_completion_wq;
|
||
|
|
bool no_disconnect;
|
||
|
|
struct work_struct reset_work;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* The endpoint files, filled by ffs_epfiles_create(),
|
||
|
|
* destroyed by ffs_epfiles_destroy().
|
||
|
|
*/
|
||
|
|
struct ffs_epfile *epfiles;
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
struct f_fs_opts {
|
||
|
|
struct usb_function_instance func_inst;
|
||
|
|
struct ffs_dev *dev;
|
||
|
|
unsigned refcnt;
|
||
|
|
bool no_configfs;
|
||
|
|
};
|
||
|
|
|
||
|
|
static inline struct f_fs_opts *to_f_fs_opts(struct usb_function_instance *fi)
|
||
|
|
{
|
||
|
|
return container_of(fi, struct f_fs_opts, func_inst);
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* U_FFS_H */
|