This commit changes FunctionFS as to make it more compliant
with coding style as well as fixes several typos.
Signed-off-by: NMichal Nazarewicz <mina86@mina86.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

usbfs_get_inode() is something completely different...

Bogosity introduced by commit 85fe4025 ("fs: do not assign default
i_ino in new_inode").
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves.  For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Use usb_string_ids_n() function to simplify string ids
registeration.
Signed-off-by: NMichal Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

FunctionFS had a bit unique name for function used to add it
to USB configuration.  Renamed as to match naming convention
of other functions.
Signed-off-by: NMichal Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

There is no gadget driver in the tree that
actually implements the ioctl operation, so
obviously it is not necessary to hold the
BKL around the call.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Michał Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Pointed out by Lucas who found the new one in a comment in
setup_percpu.c. And then I fixed the others that I grepped
for.
Reported-by: NLucas <canolucas@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix g_ffs build error, add a needed header file:

drivers/usb/gadget/f_fs.c:1064:error: 'PAGE_CACHE_SIZE' undeclared (first use in this function)
drivers/usb/gadget/f_fs.c:1065:error: 'PAGE_CACHE_SHIFT' undeclared (first use in this function)
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NMichał Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The FunctionFS is a USB composite function that can be used
with the composite framework to create an USB gadget.

>From kernel point of view it is just a composite function with
some unique behaviour.  It may be added to an USB
configuration only after the user space driver has registered
by writing descriptors and strings (the user space program has
to provide the same information that kernel level composite
functions provide when they are added to the configuration).

>From user space point of view it is a file system which when
mounted provide an "ep0" file.  User space driver need to
write descriptors and strings to that file.  It does not need
to worry about endpoints, interfaces or strings numbers but
simply provide descriptors such as if the function was the
only one (endpoints and strings numbers starting from one and
interface numbers starting from core).  The FunctionFS changes
numbers of those as needed also handling situation when
numbers differ in different configurations.

When descriptors and strings are written "ep#" files appear
(one for each declared endpoint) which handle communication on
a single endpoint.  Again, FunctionFS takes care of the real
numbers and changing of the configuration (which means that
"ep1" file may be really mapped to (say) endpoint 3 (and when
configuration changes to (say) endpoint 2)).  "ep0" is used
for receiving events and handling setup requests.

When all files are closed the function disables itself.
Signed-off-by: NMichal Nazarewicz <m.nazarewicz@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>