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>
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>
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>
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>
Johan writes:
USB-serial updates for 5.9-rc1
Here are the USB-serial updates for 5.9-rc1, including:
- console flow-control support
- simulated line-breaks on some ch341
- hardware flow-control fixes for cp210x
- break-detection and sysrq fixes for ftdi_sio
- sysrq optimisations
- input parity checking for cp210x
Included are also some new device ids and various clean ups.
All have been in linux-next with no reported issues.
* tag 'usb-serial-5.9-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial: (31 commits)
USB: serial: qcserial: add EM7305 QDL product ID
USB: serial: iuu_phoenix: fix led-activity helpers
USB: serial: sierra: clean up special-interface handling
USB: serial: cp210x: use in-kernel types in port data
USB: serial: cp210x: drop unnecessary packed attributes
USB: serial: cp210x: add support for TIOCGICOUNT
USB: serial: cp210x: add support for line-status events
USB: serial: cp210x: disable interface on errors in open
USB: serial: drop redundant transfer-buffer casts
USB: serial: drop extern keyword from function declarations
USB: serial: drop unnecessary sysrq include
USB: serial: add sysrq break-handler dummy
USB: serial: inline sysrq dummy function
USB: serial: only process sysrq when enabled
USB: serial: only set sysrq timestamp for consoles
USB: serial: ftdi_sio: fix break and sysrq handling
USB: serial: ftdi_sio: clean up receive processing
USB: serial: ftdi_sio: make process-packet buffer unsigned
USB: serial: use fallthrough pseudo-keyword
USB: serial: ch341: fix missing simulated-break margin
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
This reverts commit 5083fd7bdf.
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: 5083fd7bdf ("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>
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>
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>
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>
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>
