USB: serial: return errors from break handling

Start propagating errors to user space when setting the break state
fails.

This will be used by follow-on changes to also report when a driver or
device does not support break control.

Tested-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: mark all struct bus_type as const

Now that the driver core can properly handle constant struct bus_type,
move all of the USB subsystem struct bus_type structures as const,
placing them into read-only memory which can not be modified at runtime.

Cc: Johan Hovold <johan@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: linux-usb@vger.kernel.org
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230313182918.1312597-36-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: serial: Make ->set_termios() old ktermios const

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220816115739.10928-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: Follow-up to SPDX identifiers addition - remove now useless comments

All these files have been updated in the commit given in the Fixes: tag
below.

When the SPDX-License-Identifier: has been added, the corresponding text at
the beginning of the files has not been deleted.
All these texts are about GPL-2.0, with different variation in the wording.

Remove these now useless lines to save some LoC.

Fixes: 5fd54ace4721 ("USB: add SPDX identifiers to all remaining files in drivers/usb/")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: fix spelling mistakes in header files

Fix some spelling mistakes in comments:
trasfer ==> transfer
consumtion ==> consumption
endoint ==> endpoint
sharable ==> shareable
contraints ==> constraints
Auxilary ==> Auxiliary
correspondig ==> corresponding
interupt ==> interrupt
inifinite ==> infinite
assignement ==> assignment

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20210517094020.7310-1-thunder.leizhen@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: make usb_serial_driver::chars_in_buffer return uint

tty_operations::chars_in_buffer is being switched to return uint. Do the
same for usb_serial_driver's chars_in_buffer.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
[ johan: amend commit message ]
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: make usb_serial_driver::write_room return uint

Line disciplines expect a positive value or zero returned from
tty->ops->write_room (invoked by tty_write_room). Both of them are being
updated to return an unsigned int. Switch also
usb_serial_driver::write_room and all its users.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
[ johan: amend commit message, drop unrelated comment change ]
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: add generic support for TIOCSSERIAL

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most
serial devices is only useful for setting the close_delay and
closing_wait parameters.

The closing_wait parameter determines how long to wait for the transfer
buffers to drain during close and the default timeout of 30 seconds may
not be sufficient at low line speeds. In other cases, when for example
flow is stopped, the default timeout may instead be too long.

Add generic support for TIOCSSERIAL and TIOCGSERIAL with handling of the
three common parameters close_delay, closing_wait and line for the
benefit of all USB serial drivers while still allowing drivers to
implement further functionality through the existing callbacks.

This currently includes a few drivers that report their base baud clock
rate even if that is really only of interest when setting custom
divisors through the deprecated ASYNC_SPD_CUST interface; an interface
which only the FTDI driver actually implements.

Some drivers have also been reporting back a fake UART type, something
which should no longer be needed and will be dropped by a follow-on
patch.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: add support for multi-interface functions

A single USB function can be implemented using a group of interfaces and
this is for example commonly used for Communication Class devices.

Add support for multi-interface functions to USB serial core and export
an interface that allows drivers to claim a second sibling interface.
The interface could easily be extended to allow claiming further
interfaces if ever needed.

When a driver claims a sibling interface in probe(), core allocates
resources for any bulk in, bulk out, interrupt in and interrupt out
endpoints found also on the sibling interface.

Disconnect is implemented so that unbinding either interface will
release the other interface while disconnect() is called precisely once.

Similarly, suspend() is called when the first sibling interface is
suspended and resume() is called when the last sibling interface is
resumed by USB core.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: drop unused suspending flag

The suspending flag was added back in 2009 but no users ever followed.
Remove it.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: make remove callback return void

All usb_serial drivers return 0 in their remove callbacks and driver
core ignores the value returned by usb_serial_device_remove(). So change
the remove callback to return void and return 0 unconditionally in
usb_serial_device_remove().

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Link: https://lore.kernel.org/r/20210208143149.963644-2-uwe@kleine-koenig.org
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: remove write wait queue

The digi_acceleport driver is the only driver still using the port
write wake queue so move it to that driver's port data.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

usb: linux/usb/serial.h: drop duplicated word in comment

Drop the doubled word "set" in a comment.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Link: https://lore.kernel.org/r/20200715045701.22949-4-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: drop extern keyword from function declarations

Drop the redundant extern keyword from function declarations in the
subsystem header file to improve readability (and make it easier to spot
the global variables).

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: drop unnecessary sysrq include

There's no need to include sysrq.h in the subsystem header.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: add sysrq break-handler dummy

Add inline sysrq break-handler dummy to allow the compiler to eliminate
further code when either console or sysrq support isn't enabled and to
clearly mark the two sysrq functions as belonging together.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: inline sysrq dummy function

Inline the dummy sysrq character handling when either console support or
magic-sysrq support isn't enabled to allow the compiler to eliminate
unused code.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: drop unused iflag macro

Drop the RELEVANT_IFLAG() macro which essentially hasn't been used for
over a decade except in some remnant debug printks that were recently
removed.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: clean up throttle handling

Clean up the throttle implementation by dropping the redundant
throttle_req flag which was a remnant from back when there was only a
single read URB.

Also convert the throttled flag to an atomic bit flag.

Signed-off-by: Johan Hovold <johan@kernel.org>

usb-serial: begin switching to ->[sg]et_serial()

add such methods for usb_serial_driver, provide tty_operations
->[sg]et_serial() calling those. For now the lack of methods
in driver means ENOIOCTLCMD from usb-serial ->[sg]et_serial(),
making tty_ioctl() fall back to calling ->ioctl(). Once all
drivers are converted, we'll be returning -ENOTTY instead,
completing the switchover.

Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add calc_num_ports callback to generic driver

Add a calc_num_ports callback to the generic driver and verify that the
device has the required endpoints there instead of in core.

Note that the generic driver num_ports field was never used.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: allow subdrivers to modify port-endpoint mapping

Allow subdrivers to modify the port-endpoint mapping by passing the
endpoint descriptors to calc_num_ports.

The callback can now also be used to verify that the required endpoints
exists and abort probing otherwise.

This will allow us to get rid of a few hacks in subdrivers that are
already modifying the port-endpoint mapping (or aborting probe due to
missing endpoints), but only after the port structures have been setup.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: add endpoint sanity check to core

Allow drivers to specify a minimum number of endpoints per type, which
USB serial core will verify after subdriver probe has returned (where
the current alternate setting may have been changed).

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: allow up to 16 ports per device

Raise the arbitrary limit of how many ports a single device can claim
from eight to 16.

This specifically enables the upper eight ports of some mxuport devices.

Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: clean up endpoint and port-counter types

Use unsigned-char type for the endpoint and port counters.

Signed-off-by: Johan Hovold <johan@kernel.org>

Revert "USB: serial: make bulk_out_size a lower limit"

This reverts commit 5083fd7bdfe6760577235a724cf6dccae13652c2.

A bulk-out size smaller than the end-point size is indeed valid. The
offending commit broke the usb-debug driver for EHCI debug devices,
which use 8-byte buffers.

Fixes: 5083fd7bdfe6 ("USB: serial: make bulk_out_size a lower limit")
Reported-by: "Li, Elvin" <elvin.li@intel.com>
Cc: stable <stable@vger.kernel.org> # v3.15
Signed-off-by: Johan Hovold <johan@kernel.org>

USB: serial: make bulk_out_size a lower limit

Drivers are allowed to override the default bulk-out buffer size
(endpoint maximum packet size) in order to increase throughput, but it
does not make much sense to allow buffers smaller than the default.

Note that this is already how bulk_in_size is defined.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

USB: serial: export usb_serial_generic_write_start

Export usb_serial_generic_write_start which is needed when implementing
a custom resume function while still relying on the generic write
implementation.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: increase the number of devices we support

We had the limit of 255 USB to serial devices on one system for almost
15 years, with no complaints. But now it's time to move on from these
tiny "baby" systems, and bump the number up to 512, which should last
us a few more years:
"512 is a nice number" -- Tobias Winter

Note, this is still a static value, and uses up tty core memory with
this many tty devices allocated. Converting the driver to use
TTY_DRIVER_DYNAMIC_DEV is the next thing to do in order to remove this
limitation.

Reported-by: Tobias Winter <tobias@linuxdingsda.de>
Tested-by: Tobias Winter <tobias@linuxdingsda.de>
Reviewed-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: make minor allocation dynamic

This moves the allocation of minor device numbers from a static array to
be dynamic, using the idr interface. This means that you could
potentially get "gaps" in a minor number range for a single USB serial
device with multiple ports, but all should still work properly.

We remove the 'minor' field from the usb_serial structure, as it no
longer makes any sense for it (use the field in the usb_serial_port
structure if you really want to know this number), and take the fact
that we were overloading a number in this field to determine if we had
initialized the minor numbers or not, and just use a flag variable
instead.

Note, we still have the limitation of 255 USB to serial devices in the
system, as that is all we are registering with the TTY layer at this
point in time.

Tested-by: Tobias Winter <tobias@linuxdingsda.de>
Reviewed-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: ports: add minor and port number

The usb_serial_port structure had the number field, which was the minor
number for the port, which almost no one really cared about. They
really wanted the number of the port within the device, which you had to
subtract from the minor of the parent usb_serial_device structure. To
clean this up, provide the real minor number of the port, and the number
of the port within the serial device separately, as these numbers might
not be related in the future.

Bonus is that this cleans up a lot of logic in the drivers, and saves
lines overall.

Tested-by: Tobias Winter <tobias@linuxdingsda.de>
Reviewed-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

--
drivers/staging/serqt_usb2/serqt_usb2.c | 21 +++--------
drivers/usb/serial/ark3116.c | 2 -
drivers/usb/serial/bus.c | 6 +--
drivers/usb/serial/console.c | 2 -
drivers/usb/serial/cp210x.c | 2 -
drivers/usb/serial/cypress_m8.c | 4 +-
drivers/usb/serial/digi_acceleport.c | 6 ---
drivers/usb/serial/f81232.c | 5 +-
drivers/usb/serial/garmin_gps.c | 6 +--
drivers/usb/serial/io_edgeport.c | 58 ++++++++++++--------------------
drivers/usb/serial/io_ti.c | 21 ++++-------
drivers/usb/serial/keyspan.c | 29 +++++++---------
drivers/usb/serial/metro-usb.c | 4 +-
drivers/usb/serial/mos7720.c | 37 +++++++++-----------
drivers/usb/serial/mos7840.c | 52 +++++++++-------------------
drivers/usb/serial/opticon.c | 2 -
drivers/usb/serial/pl2303.c | 2 -
drivers/usb/serial/quatech2.c | 7 +--
drivers/usb/serial/sierra.c | 2 -
drivers/usb/serial/ti_usb_3410_5052.c | 10 ++---
drivers/usb/serial/usb-serial.c | 7 ++-
drivers/usb/serial/usb_wwan.c | 2 -
drivers/usb/serial/whiteheat.c | 20 +++++------
include/linux/usb/serial.h | 6 ++-
24 files changed, 133 insertions(+), 180 deletions(-)

USB: serial: add generic wait_until_sent implementation

Add generic wait_until_sent implementation which polls for empty
hardware buffers using the new port-operation tx_empty.

The generic implementation will be used for all sub-drivers that
implement tx_empty but does not define wait_until_sent.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add wait_until_sent operation

Add wait_until_sent operation which can be used to wait for hardware
buffers to drain.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove unused MSR-wait queue

Remove the port MSR-wait queue now that all drivers have been migrated
to the tty-port queue.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add generic get_icount implementation

Add generic get_icount implementation that subdrivers relying on the
port interrupt counters can use.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add generic TIOCMIWAIT implementation

Add generic TIOCMIWAIT implementation which correctly handles hangup,
USB-device disconnect, does not rely on the deprecated sleep_on
functions and hence does not suffer from the races currently affecting
several usb-serial drivers.

This makes it much easier to add TIOCMIWAIT support to subdrivers as the
tricky details related to hangup and disconnect (e.g. atomicity, that
the private port data may have been freed when woken up, and waking up
processes at disconnect) have been handled once and for all.

To add support to a subdriver, simply set the tiocmiwait-port-operation
field, update the port icount fields and wake up any process sleeping on
the tty-port modem-status-change wait queue on changes.

Note that the tty-port initialised flag can be used to detect
disconnected as the port will be hung up as part of disconnect (and
cannot be reactivated due to the disconnected flag). However, as the
tty-port implementation currently wakes up processes before calling port
shutdown, the tty-hupping flag must also be checked to detect hangup for
now.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add tiocmiwait subdriver operation

Add tiocmiwait operation to struct usb_serial_driver.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove generic release callback

Remove empty generic release implementation and make the release
callback non-mandatory (like attach, probe and disconnect).

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove generic disconnect callback

Remove the now empty generic disconnect callback and make the disconnect
callback non-mandatory.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add modem-status-change wait queue

Add modem-status-change wait queue to struct usb_serial_port that
subdrivers can use to implement TIOCMIWAIT.

Currently subdrivers use a private wait queue which may have been
released when waking up after device disconnected.

Note that we're adding a new wait queue rather than reusing the tty-port
one as we do not want to get woken up at hangup (yet).

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ezusb: add support for Cypress FX2LP

This Patch adds support for the newer Cypress FX2LP. It also adapts
three drivers currently using ezusb to the interface change. (whiteheat
and keyspan[_pda])

Signed-off-by: René Bürgel <rene.buergel@sohard.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: Serial: usb-serial: remove debug module parameter

Now that all usb-serial modules are only using dev_dbg()
the debug module parameter does not do anything at all, so
remove it to reduce any confusion if someone were to try
to use it.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove debug parameter from usb_serial_debug_data()

We should use dev_dbg() for usb_serial_debug_data() like all of the rest
of the usb-serial drivers use, so remove the debug parameter as it's not
needed.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove dbg() from usb/serial.h

Now that all in-kernel users of the dbg() macro are gone, we can remove
it from the include/linux/usb/serial.h file.

Good riddance.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: ezusb: remove dependancy on usb_serial

This patch removes the dependency on the usb_serial interface and names
some magic constants

Signed-off-by: René Bürgel <rene.buergel@sohard.de>
--
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: move usb_serial_debug_data to use %*ph

Now that we have a printk modifier for data streams, use it instead of
rolling our own.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: hook up reset_resume callback

The callback is now hooked up for any USB to serial driver that wants
it. We only register the callback if any of the usb-serial structures
want it, this keeps the USB core happy.

Thanks to Alan Stern for the ideas on how to do this.

Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: rework usb_serial_register/deregister_drivers()

This reworks the usb_serial_register_drivers() and
usb_serial_deregister_drivers() to not need a pointer to a struct
usb_driver anymore. The usb_driver structure is now created dynamically
and registered and unregistered as needed.

This saves lines of code in each usb-serial driver. All in-kernel users
of these functions were also fixed up at this time. The pl2303 driver
was tested that everything worked properly.

Thanks for the idea to do this from Alan Stern.

Cc: Adhir Ramjiawan <adhirramjiawan0@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Aleksey Babahin <tamerlan311@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrew Worsley <amworsley@gmail.com>
Cc: Bart Hartgers <bart.hartgers@gmail.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Donald Lee <donald@asix.com.tw>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Gary Brubaker <xavyer@ix.netcom.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Matthias Urlichs <smurf@smurf.noris.de>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Michal Sroczynski <msroczyn@gmail.com>
Cc: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Preston Fick <preston.fick@silabs.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Rigbert Hamisch <rigbert@gmx.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Support Department <support@connecttech.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Cc: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
Cc: Wang YanQing <Udknight@gmail.com>
Cc: William Greathouse <wgreathouse@smva.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove bizarre generic_serial probe function

I can't remember why I wrote it like this many many years ago, but it's
not needed at all, let's rely on the usb-serial core for this function,
especially as it is being overridden by it anyway.

This lets us make usb_serial_probe() a static function, which it should
be.

Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove usb_serial_disconnect call in all drivers

This is now set by the usb-serial core, no need for the driver to
individually set it.

Thanks to Alan Stern for the idea to get rid of it.

Cc: William Greathouse <wgreathouse@smva.com>
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Gary Brubaker <xavyer@ix.netcom.com>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Matthias Urlichs <smurf@smurf.noris.de>
Cc: Support Department <support@connecttech.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Bart Hartgers <bart.hartgers@gmail.com>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Preston Fick <preston.fick@silabs.com>
Cc: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Andrew Worsley <amworsley@gmail.com>
Cc: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Aleksey Babahin <tamerlan311@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Donald Lee <donald@asix.com.tw>
Cc: Julia Lawall <julia@diku.dk>
Cc: Michal Sroczynski <msroczyn@gmail.com>
Cc: Wang YanQing <Udknight@gmail.com>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Cc: Rigbert Hamisch <rigbert@gmx.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Adhir Ramjiawan <adhirramjiawan0@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: fix bug in serial driver unregistration

This patch (as1536) fixes a bug in the USB serial core. Unloading and
reloading a serial driver while a serial device is plugged in causes
errors because of the code in usb_serial_disconnect() that tries to
make sure the port_remove method is called. With the new order of
driver registration introduced in the 3.4 kernel, this is definitely
not the right thing to do (if indeed it ever was).

The patch removes that whole section code, along with the mechanism
for keeping track of each port's registration state, which is no
longer needed. The driver core can handle all that stuff for us.

Note: This has been tested only with one or two USB serial drivers.
In theory, other drivers might still run into trouble. But if they
do, it will be the fault of the drivers, not of this patch -- that is,
the drivers will need to be fixed.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: use module_driver() macro

Now that module_driver() can handle varargs, use it instead of rolling
our own version.

Cc: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: create module_usb_serial_driver macro

Now that Alan Stern has cleaned up the usb serial driver registration,
we have the ability to create a module_usb_serial_driver macro to make
things a bit simpler, like the other *_driver macros created.

But, as we need two functions here, we can't reuse the existing
module_driver() macro, so we need to roll our own.

Here's a patch implementing module_usb_serial_driver() and it converts
the pl2303 driver to use it, showing a nice cleanup.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: remove usb_serial_register and usb_serial_deregister

No one uses them anymore, they should be using the safer
usb_serial_register_drivers() and usb_serial_deregister_drivers()
functions instead.

Thanks to Alan Stern for writing these functions and porting all
in-kernel users to them.

Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb-serial: new API for driver registration

This patch (as1522) adds two new routines to the usb-serial core, for
registering and unregistering serial drivers. Instead of registering
the usb_driver and usb_serial_drivers separately, with error checking
for each one, the drivers can all be registered and unregistered by a
single function call. This reduces duplicated code.

More importantly, the new core routines change the order in which the
drivers are registered. Currently the usb-serial drivers are all
registered first and the usb_driver is done last, which leaves a
window for problems. A udev script may quickly add a new dynamic-ID
for a usb-serial driver, causing the corresponding usb_driver to be
probed. If the usb_driver hasn't been registered yet then an oops
will occur.

The new routine prevents such problems by registering the usb_driver
first. To insure that it gets probed properly for already-attached
serial devices, we call driver_attach() after all the usb-serial
drivers have been registered.

Along with adding the new routines, the patch modifies the "generic"
serial driver to use them. Further patches will similarly modify all
the other in-tree USB serial drivers.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add macro for console error reporting

Add macro which prints an error message only once if port is used a
console.

Reporting errors in a write path when port is used as a console could
otherwise result in an infinite loop.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: serial: add support for multiple read urbs

Add support for multiple read urbs to generic read implementation.

Use a static array of two read urbs for now which is enough to get a
50% throughput increase in one test setup.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: remove write_urb_busy field from usb_serial_port

Remove no longer used write_urb_busy field from struct usb_serial_port.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial drivers need to use larger bulk-in buffers

When a driver doesn't know how much data a device is going to send,
the buffer size should be at least as big as the endpoint's maxpacket
value. The serial drivers don't follow this rule; many of them
request only 256-byte bulk-in buffers. As a result, they suffer
overflow errors if a high-speed device wants to send a lot of data,
because high-speed bulk endpoints are required to have a maxpacket
size of 512.

This patch (as1450) fixes the problem by using the driver's
bulk_in_size value as a minimum, always allocating buffers no smaller
than the endpoint's maxpacket size.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Flynn Marquardt <flynn@flynnux.de>
CC: <stable@kernel.org> [after .39-rc1 is out]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: remove filp from the USB tty ioctls

We don't use it so we can trim it from here as we try and stamp the file
object dependencies out of the serial code.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tiocmset: kill the file pointer argument

Doing tiocmget was such fun we should do tiocmset as well for the same
reasons

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tiocmget: kill off the passing of the struct file

We don't actually need this and it causes problems for internal use of
this functionality. Currently there is a single use of the FILE * pointer.
That is the serial core which uses it to check tty_hung_up_p. However if
that is true then IO_ERROR is also already set so the check may be removed.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: handle Data Carrier Detect changes

Alan's commit 335f8514f200e63d689113d29cb7253a5c282967 introduced
.carrier_raised function in several drivers. That also means
tty_port_block_til_ready can now suspend the process trying to open the serial
port when Carrier Detect is low and put it into tty_port.open_wait queue. We
need to wake up the process when Carrier Detect goes high and trigger TTY
hangup when CD goes low.

Some of the devices do not report modem status line changes, or at least we
don't understand the status message, so for those we remove .carrier_raised
again.

Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: Make tiocgicount a handler

Dan Rosenberg noted that various drivers return the struct with uncleared
fields. Instead of spending forever trying to stomp all the drivers that
get it wrong (and every new driver) do the job in one place.

This first patch adds the needed operations and hooks them up, including
the needed USB midlayer and serial core plumbing.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: drop tty argument from usb_serial_handle_sysrq_char()

Since handle_sysrq() does not take tty as argument anymore we can
drop it from usb_serial_handle_sysrq_char() as well.

Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

USB: include/usb/*.h checkpatch cleanup

Lots of minor formatting cleanups in includes/usb/ to make checkpatch
happier.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: remove multi-urb write from generic driver

Remove multi-urb write from the generic driver and simplify the
prepare_write_buffer prototype:

int (*prepare_write_buffer)(struct usb_serial_port *port,
void *dest, size_t size);

The default implementation simply fills dest with data from port write
fifo but drivers can override it if they need to process the outgoing
data (e.g. add headers).

Turn ftdi_sio into a generic fifo-based driver, which lowers CPU usage
significantly for small writes while retaining maximum throughput.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: reimplement generic fifo-based writes

Reimplement fifo-based writes in the generic driver using a multiple
pre-allocated urb scheme.

In contrast to multi-urb writes, no allocations (of urbs or buffers) are
made during run-time and there is less pressure on the host stack
queues as currently only two urbs are used (implementation is generic
and can handle more than two urbs as well, though).

Initial tests using ftdi_sio show that the implementation achieves the
same (maximum) throughput at high baudrates as multi-urb writes. The CPU
usage is much lower than for multi-urb writes for small write requests
and only slightly higher for large (e.g. 2k) requests (due to extra copy
via fifo?).

Also outperforms multi-urb writes for small write requests on an
embedded arm-9 system, where multi-urb writes are CPU-bound at high
baudrates (perf reveals that a lot of time is spent in the host stack
enqueue function -- could perhaps be a bug as well).

Keeping the original write_urb, buffer and flag for now as there are
other drivers depending on them.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: generalise write buffer preparation

Generalise write buffer preparation.

This allows for drivers to manipulate (e.g. add headers) to bulk out
data before it is sent.

This adds a new function pointer to usb_serial_driver:

int (*prepare_write_buffer)(struct usb_serial_port *port,
void **dest, size_t size, const void *src, size_t count);

The function is generic and can be used with either kfifo-based or
multi-urb writes:

If *dest is NULL the implementation should allocate dest.
If src is NULL the implementation should use the port write fifo.

If not set, a generic implementation is used which simply uses memcpy or
kfifo_out.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: re-implement multi-urb writes in generic driver

Use dynamic transfer buffer sizes since it is more efficient to let the
host controller do the partitioning to fit endpoint size. This way we
also do not use more than one urb per write request.

Replace max_in_flight_urbs with multi_urb_write flag in struct
usb_serial_driver to enable multi-urb writes.

Use MAX_TX_URBS=40 and a max buffer size of PAGE_SIZE to prevent DoS
attacks.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: generalise generic read implementation

Add process_read_urb to usb_serial_driver so that a driver can rely on
the generic read (and throttle) mechanism but still do device specific
processing of incoming data (such as adding tty_flags before pushing to
line discipline).

The default generic implementation handles sysrq for consoles but
otherwise simply pushes to tty.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: refactor read urb submission in generic driver

Use the already exported function for submitting the read urb associated
with a usb_serial_port.

Make sure it returns the result of usb_submit_urb and rename to the
more descriptive usb_serial_generic_submit_read_urb.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: allow drivers to define bulk buffer sizes

Allow drivers to define custom bulk in/out buffer sizes in struct
usb_serial_driver. If not set, fall back to the default buffer size
which matches the endpoint size.

Three drivers are currently freeing the pre-allocated buffers and
allocating larger ones to achieve this at port probe (ftdi_sio) or even
at port open (ipaq and iuu_phoenix), which needless to say is suboptimal.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

usb-serial: Use tty_port version console instead of usb_serial_port

Replace all instances of using the console variable in struct
usb_serial_port with the struct tty_port version.

CC: Alan Cox <alan@linux.intel.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Oliver Neukum <oliver@neukum.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: linux-usb@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: Extend and neaten dbg macros

Add format/argument validation for #ifndef DEBUG dbg macro
Neaten dbg macro definitions

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

Fix usb_serial_probe() problem introduced by the recent kfifo changes

The USB serial code was a new user of the kfifo API, and it was missed
when porting things to the new kfifo API.

Please make the write_fifo in place. Here is my patch to fix the
regression and full ported version.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Reported-and-tested-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

usb_serial: Kill port mutex

The tty port has a port mutex used for all the port related locking so we
don't need the one in the USB serial layer any more.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: don't call release without attach

This patch (as1295) fixes a recently-added bug in the USB serial core.
If certain kinds of errors occur during probing, the core may call a
serial driver's release method without previously calling the attach
method. This causes some drivers (io_ti in particular) to perform an
invalid memory access.

The patch adds a new flag to keep track of whether or not attach has
been called.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Jean-Denis Girard <jd.girard@sysnux.pf>
CC: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: use kfifo to buffer usb-generic serial writes

When do_output_char() attempts to write a carriage return/line feed sequence,
it first checks to see how much buffer room is available. If there are at least
two characters free, it will write the carriage return/line feed with two calls
to tty_put_char(). It calls the tty_operation functions write() for devices that
don't support the tty_operations function put_char(). If the USB generic serial
device's write URB is not in use, it will return the buffer size when asked how
much room is available. The write() of the carriage return will cause it to mark
the write URB busy, so the subsequent write() of the line feed will be ignored.

This patch uses the kfifo infrastructure to implement a write FIFO that
accurately returns the amount of space available in the buffer.

Signed-off-by: David VomLehn <dvomlehn@cisco.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: USB serial termios bits

Various drivers have hacks to mangle termios structures. This stems from
the fact there is no nice setup hook for configuring the termios settings
when the port is created

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: USB does not need the filp argument in the drivers

And indeed none of them use it. Clean this up as it will make moving to a
standard open method rather easier.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: Fix USB kref leak

The sysrq code acquired a kref leak. Fix it by passing the tty separately
from the caller (thus effectively using the callers kref which all the
callers hold anyway)

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

USB: usb-serial: replace shutdown with disconnect, release

This patch (as1254) splits up the shutdown method of usb_serial_driver
into a disconnect and a release method.

The problem is that the usb-serial core was calling shutdown during
disconnect handling, but drivers didn't expect it to be called until
after all the open file references had been closed. The result was an
oops when the close method tried to use memory that had been
deallocated by shutdown.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb-serial: call port_probe and port_remove at the right times

This patch (as1253) prevents the usb-serial core from calling a
driver's port_probe and port_remove methods more than once per port.
It also removes some unnecessary try_module_get() calls and adds a
missing port_remove method call in a failure path.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial: usb_debug,usb_generic_serial: implement sysrq and serial break

The usb_debug driver was modified to implement serial break handling
by using a "magic" data packet comprised of the sequence:

0x00 0xff 0x01 0xfe 0x00 0xfe 0x01 0xff

When the tty layer requests a serial break the usb_debug driver sends
the magic packet. On the receiving side the magic packet is thrown
away or a sysrq is activated depending on what kernel .config options
have been set.

The generic serial driver was modified as well as the usb serial
headers to generically implement sysrq processing in the same way the
non usb uart based drivers implement the sysrq handling. This will
allow other usb serial devices to implement sysrq handling as desired.

The new usb serial functions are named similarly and implemented
similarly to the uart functions as follows:

usb_serial_handle_break <-> uart_handle_break
usb_serial_handle_sysrq_char <-> uart_handle_sysrq_char

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb_debug, usb_generic_serial: implement multi urb write

The usb_debug driver, when used as the console, will always fail to
insert the carriage return and new line sequence as well as randomly
drop console output. This is a result of only having the single
write_urb and that the tty layer will have a lock that prevents the
processing of the back to back urb requests.

The solution is to allow more than one urb to be outstanding and have
a slightly deeper transmit queue. The idea and some code is borrowed
from the ftdi_sio usb driver.

The generic usb serial driver was modified so as to allow the classic
method of 1 write urb, or a multi write urb scheme with N allowed
outstanding urbs where N is controlled by max_in_flight_urbs. When
max_in_flight_urbs in a "struct usb_serial_driver" is non zero the
multi write urb scheme will be used.

The size of 4000 was selected for the usb_debug driver so that the
driver lowers possibility of losing the queued console messages during
the kernel startup.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

tty: Bring the usb tty port structure into more use

This allows us to clean stuff up, but is probably also going to cause
some app breakage with buggy apps as we now implement proper POSIX behaviour
for USB ports matching all the other ports. This does also mean other apps
that break on USB will now work properly.

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tty: Update some of the USB kernel doc

Updates some usb_serial_port members documentation.

Signed-off-by: Leandro Dorileo <ldorileo@gmail.com>
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

USB: serial: introduce a flag into the usb serial layer to tell drivers that their URBs are killed due to suspension

This patch introduces a flag into the usb serial layer to tell drivers
that their URBs are killed due to suspension. That is necessary to let
drivers know whether they should report an error back.

Signed-off-by: Oliver Neukum <oneukum@suse.de>

Hi Greg,

this is for 2.6.30. Patches to use this in drivers are under development.

Regards
Oliver

USB: Fix spelling in usb/serial.h

Fixes a minor typo in the comments for usb_set_serial_data.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

usb-serial: don't release unregistered minors

This patch (as1121) fixes a bug in the USB serial core. When a device
is unregistered, the core will give back its minors -- even if the
device hasn't been assigned any!

The patch reserves the highest minor value (255) to mean that no minor
was assigned. It also removes some dead code and does a small style
fixup.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

usb_serial: API all change

USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.

So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.

Longer term we need a proper tty as console abstraction

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

USB: serial: remove endpoints setting checks from core and header

Remove the unused check for num_interrupt and friends as well as remove
them from the header file because no usb-serial drivers no longer
reference them.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: Standardize inclusion protection and add where missing.

For the header files in include/linux/usb, add missing multiple
inclusion protection and standardize what's already there. The
apparent standards:

* macro name of __LINUX_USB_headerfile_H
* inclusion protection placed after leading comment block
* macro name added as a comment on the final #endif
* any obvious trivial whitespace cleanup associated with the above

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: fix codingstyle issues in include/linux/usb/

Fixes a number of coding style issues in the USB public header files.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: stop io performed by mos7720 upon close()

This fixes a problem where the mos7720 driver will make io to a device from
which it has been logically disconnected. It does so by introducing a flag by
which the generic usb serial code can signal the subdrivers their
disconnection and appropriate locking.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb_serial: clean tty reference in the last close

When a usb serial adapter is used as console, the usb serial console
driver bumps the open_count on the port struct used but doesn't attach
a real tty to it (only a fake one temporaly). If this port is opened later
using the regular character device interface, the open method won't
initialize the port, which is the expected, and will receive a brand new
tty struct created by tty layer, which will be stored in port->tty.

When the last close is issued, open_count won't be 0 because of the
console usage and the port->tty will still contain the old tty value. This
is the last ttyUSB<n> close so the allocated tty will be freed by the
tty layer. The usb_serial and usb_serial_port are still in use by the
console, so port_free() won't be called (serial_close() ->
usb_serial_put() -> destroy_serial() -> port_free()), so the scheduled
work (port->work, usb_serial_port_work()) will still run. And
usb_serial_port_work() does:
(...)
tty = port->tty;
if (!tty)
return;

tty_wakeup(tty);
which causes (manually copied):

Faulting instruction address: 0x6b6b6b68
Oops: Kernel access of bad area, sig: 11 [#1]
PREEMPT PowerMac
Modules linked in: binfmt_misc ipv6 nfs lockd nfs_acl sunrpc dm_snapshot dm_mirror dm_mod hfsplus uinput ams input_polldev genrtc cpufreq_powersave i2c_powermac therm_adt746x snd_aoa_codec_tas snd_aoa_fabric_layout snd_aoa joydev snd_aoa_i2sbus snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc pmac_zilog serial_core evdev ide_cd cdrom snd appletouch soundcore snd_aoa_soundbus bcm43xx firmware_class usbhid ieee80211softmac ff_memless firewire_ohci firewire_core ieee80211 ieee80211_crypt crc_itu_t sungem sungem_phy uninorth_agp agpart ssb
NIP: 6b6b6b68 LR: c01b2108 CTR: 6b6b6b6b
REGS: c106de80 TRAP: 0400 Not tainted (2.6.24-rc2)
MSR: 40009032 <EE,ME,IR,DR> CR: 82004024 XER: 00000000
TASK = c106b4c0[5] 'events/0' THREAD: c106c000
GPR00: 6b6b6b6b c106df30 c106b4c0 c2d613a0 00009032 00000001 00001a00 00000001
GPR08: 00000008 00000000 00000000 c106c000 42004028 00000000 016ffbe0 0171a724
GPR16: 016ffcf4 00240e24 00240e70 016fee68 016ff9a4 c03046c4 c0327f50 c03046fc
GPR24: c106b6b9 c106b4c0 c101d610 c106c000 c02160fc c1eac1dc c2d613ac c2d613a0
NIP [6b6b6b68] 0x6b6b6b68
LR [c01b2108] tty_wakeup+0x6c/0x9c
Call Trace:
[c106df30] [c01b20e8] tty_wakeup+0x4c/0x9c (unreliable)
[c106df40] [c0216138] usb_serial_port_work+0x3c/0x78
[c106df50] [c00432e8] run_workqueue+0xc4/0x15c
[c106df90] [c0043798] worker_thread+0xa0/0x124
[c106dfd0] [c0048224] kthread+0x48/0x84
[c106dff0] [c00129bc] kernel_thread+0x44/0x60
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
Slab corruption: size-2048 start=c2d613a0, len=2048
Redzone: 0x9f911029d74e35b/0x9f911029d74e35b.
Last user: [<c01b16d8>](release_one_tty+0xbc/0xf4)
050: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Prev obj: start=c2d60b88, len=2048
Redzone: 0x9f911029d74e35b/0x9f911029d74e35b.
Last user: [<c00f30ec>](show_stat+0x410/0x428)
000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b

This patch avoids this, clearing port->tty considering if the port is
used as serial console or not

Signed-off-by: Aristeu Rozanski <arozansk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: serial core should respect driver requirements

This patch (as997) fixes a bug in the USB serial core. The core needs
to pay attention to drivers' requirements regarding the number and
type of endpoints a device has.

At the same time, the patch changes the NUM_DONT_CARE constant (which
is stored in a single-byte field) from -1 to a safer, unsigned value.
It also improves the kerneldoc for several fields in the
usb_serial_driver structure.

Finally, the patch replaces a list_for_each() with list_for_each_entry().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: suspend support for usb serial

this implements generic support for suspend/resume for usb serial.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: add flow control to usb-serial generic driver.

I added two fields to struct usb_serial_port to keep track of the
throttle state. Other usb-serial drivers typically use private data for
such things, but the generic driver can not really do that because some
of its code is also used by other drivers (which may have their own
private data needs).

As it is, I am not sure that this patch is useful in all scenarios.
It is certainly helpful for low-bandwidth devices that can hold their
data in response to throttling. But for devices that pump data in
real-time as fast as possible (webcam, A/D converter, etc), throttling
may actually cause more data loss.

From: Joris van Rantwijk <jorispubl@xs4all.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB serial: add dynamic id support to usb-serial core

Thanks to Johannes Hölzl <johannes.hoelzl@gmx.de> for fixing a few
things and getting it all working properly.

This adds support for dynamic usb ids to the usb serial core. The file
"new_id" will show up under the usb serial driver, not the usb driver
associated with the usb-serial driver (yeah, it can be a bit confusing
at first glance...)

This patch also modifies the USB core to allow the usb-serial core to
reuse much of the dynamic id logic.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Johannes Hölzl <johannes.hoelzl@gmx.de>

[PATCH] tty: switch to ktermios

This is the grungy swap all the occurrences in the right places patch that
goes with the updates. At this point we have the same functionality as
before (except that sgttyb() returns speeds not zero) and are ready to
begin turning new stuff on providing nobody reports lots of bugs

If you are a tty driver author converting an out of tree driver the only
impact should be termios->ktermios name changes for the speed/property
setting functions from your upper layers.

If you are implementing your own TCGETS function before then your driver
was broken already and its about to get a whole lot more painful for you so
please fix it 8)

Also fill in c_ispeed/ospeed on init for most devices, although the current
code will do this for you anyway but I'd like eventually to lose that extra
paranoia

[akpm@osdl.org: bluetooth fix]
[mp3@de.ibm.com: sclp fix]
[mp3@de.ibm.com: warning fix for tty3270]
[hugh@veritas.com: fix tty_ioctl powerpc build]
[jdike@addtoit.com: uml: fix ->set_termios declaration]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.

(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.

(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

[PATCH] USB: move usb-serial.h to include/linux/usb/

USB serial outside of the kernel tree can not build properly due to
usb-serial.h being buried down in the source tree. This patch moves the
location of the file to include/linux/usb and fixes up all of the usb
serial drivers to handle the move properly.

Cc: Sergei Organov <osv@javad.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>