Commit Graph

254 Commits

Author SHA1 Message Date
Johan Hovold d51bdb93ca USB: serial: fix runtime PM after driver unbind
Since commit c2b71462d2 ("USB: core: Fix bug caused by duplicate
interface PM usage counter") USB drivers must always balance their
runtime PM gets and puts, including when the driver has already been
unbound from the interface.

Leaving the interface with a positive PM usage counter would prevent a
later bound driver from suspending the device.

Fixes: c2b71462d2 ("USB: core: Fix bug caused by duplicate interface PM usage counter")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191001084908.2003-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-04 14:38:46 +02:00
Mauro Carvalho Chehab ecefae6db0 docs: usb: rename files to .rst and add them to drivers-api
While there are a mix of things here, most of the stuff
were written from Kernel developer's PoV. So, add them to
the driver-api book.

A follow up for this patch would be to move documents from
there that are specific to sysadmins, adding them to the
admin-guide.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-20 14:28:36 +02:00
Johan Hovold 579bebe5dd USB: serial: fix initial-termios handling
The USB-serial driver init_termios callback is used to override the
default initial terminal settings provided by USB-serial core.

After a bug was fixed in the original implementation introduced by
commit fe1ae7fdd2 ("tty: USB serial termios bits"), the init_termios
callback was no longer called just once on first use as intended but
rather on every (first) open.

This specifically meant that the terminal settings saved on (final)
close were ignored when reopening a port for drivers overriding the
initial settings.

Also update the outdated function header referring to the creation of
termios objects.

Fixes: 7e29bb4b77 ("usb-serial: fix termios initialization logic")
Signed-off-by: Johan Hovold <johan@kernel.org>
2019-04-26 08:37:53 +02:00
Al Viro 930236a308 complete ->[sg]et_serial() switchover
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-13 00:50:43 -04:00
Al Viro 81732b26e0 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>
2018-10-13 00:50:34 -04:00
Linus Torvalds 07c4dd3435 USB/PHY patches for 4.18-rc1
Here is the big USB pull request for 4.18-rc1.
 
 Lots of stuff here, the highlights are:
 	- phy driver updates and new additions
 	- usual set of xhci driver updates
 	- normal set of musb updates
 	- gadget driver updates and new controllers
 	- typec work, it's getting closer to getting fully out of the
 	  staging portion of the tree.
 	- lots of minor cleanups and bugfixes.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB and PHY updates from Greg KH:
 "Here is the big USB pull request for 4.18-rc1.

  Lots of stuff here, the highlights are:

   - phy driver updates and new additions

   - usual set of xhci driver updates

   - normal set of musb updates

   - gadget driver updates and new controllers

   - typec work, it's getting closer to getting fully out of the staging
     portion of the tree.

   - lots of minor cleanups and bugfixes.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'usb-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (263 commits)
  Revert "xhci: Reset Renesas uPD72020x USB controller for 32-bit DMA issue"
  xhci: Add quirk to zero 64bit registers on Renesas PCIe controllers
  xhci: Allow more than 32 quirks
  usb: xhci: force all memory allocations to node
  selftests: add test for USB over IP driver
  USB: typec: fsusb302: no need to check return value of debugfs_create_dir()
  USB: gadget: udc: s3c2410_udc: no need to check return value of debugfs_create functions
  USB: gadget: udc: renesas_usb3: no need to check return value of debugfs_create functions
  USB: gadget: udc: pxa27x_udc: no need to check return value of debugfs_create functions
  USB: gadget: udc: gr_udc: no need to check return value of debugfs_create functions
  USB: gadget: udc: bcm63xx_udc: no need to check return value of debugfs_create functions
  USB: udc: atmel_usba_udc: no need to check return value of debugfs_create functions
  USB: dwc3: no need to check return value of debugfs_create functions
  USB: dwc2: no need to check return value of debugfs_create functions
  USB: core: no need to check return value of debugfs_create functions
  USB: chipidea: no need to check return value of debugfs_create functions
  USB: ehci-hcd: no need to check return value of debugfs_create functions
  USB: fhci-hcd: no need to check return value of debugfs_create functions
  USB: fotg210-hcd: no need to check return value of debugfs_create functions
  USB: imx21-hcd: no need to check return value of debugfs_create functions
  ...
2018-06-05 16:14:12 -07:00
Johan Hovold 79ef51894a USB: serial: use tty_port_register_device()
We already have the tty port when probing a usb-serial port so use
tty_port_register_device() directly instead of tty_port_install() later
to set up the port link.

This is a step towards enabling serdev for usb-serial (but we need to
determine how to handle hotplugging first).

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2018-05-17 11:22:00 +02:00
Christoph Hellwig 8a8dcabffb tty: replace ->proc_fops with ->proc_show
Just set up the show callback in the tty_operations, and use
proc_create_single_data to create the file without additional
boilerplace code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:24:30 +02:00
Johan Hovold 627cfa89b1 USB: serial: fix module-license macros
Several GPL-2.0 drivers used "GPL" rather than "GPL v2" in their
MODULE_LICENSE macros; fix the macros to match the licenses.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:58:00 +01:00
Greg Kroah-Hartman 6ca98bc284 USB: serial: Remove redundant license text
Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:55:38 +01:00
Greg Kroah-Hartman 5fd54ace47 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>
2017-11-04 11:48:02 +01:00
Johan Hovold 2944fd27d1 USB: serial: drop unused core USB driver
Drop the usb-serial-core USB driver that was registered at module init
but then never used.

This was a remnant dating back to 2004 (!) when this struct usb_driver
was used for the generic driver; see commit bbc53b7d7322 ("USB: fix bug
where removing usb-serial modules or usb serial devices could oops") in
the tglx bitkeeper-history archive.

Note that every usb-serial driver (including the generic one) registers
its own USB (interface) driver along with its usb-serial bus drivers.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-10-13 09:48:55 +02:00
Johan Hovold c22ac6d29f USB: serial: propagate late probe errors
Propagate errnos for late probe errors (e.g. -ENOMEM on allocation
failures) instead of always returning -EIO.

Note that some drivers are currently returning -ENODEV from their attach
callbacks when a device is not supported, but this has also been mapped
to -EIO.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-06-21 09:40:07 +02:00
Johan Hovold 45e5d4d418 USB: serial: refactor port endpoint setup
Make the probe callback more readable by refactoring the port
endpoint-resource setup by adding four helper functions.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-06-21 09:38:58 +02:00
Johan Hovold e1fdd5b262 USB: serial: drop obsolete open-race workaround
Commit a65a6f14dc ("USB: serial: fix race between probe and open")
fixed a race between probe and open, which could lead to crashes when a
not yet fully initialised port was being opened.

This race was later incidentally closed by commit 7e73eca6a7 ("TTY:
move cdev_add to tty_register_device") which moved character-device
registration from tty_register_driver to tty_register_device, which
isn't called until the port has been fully set up.

Remove the now redundant workaround which had the negative side effect
of not allowing a port to be opened immediately after user space had
been notified of a new tty device.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2017-03-31 13:14:39 +02:00
Johan Hovold 9fda620a5f USB: serial: move pl2303 hack out of usb-serial core
Some pl2303 devices require the use of the interrupt endpoint of an
unrelated interface. This has so far been dealt with in usb-serial core,
but can now be moved to a driver calc_num_ports callback.

Note that we relax the endpoint requirements checked by core and instead
verify that we have an interrupt-in endpoint in calc_num_ports for all
devices so that the hack can first be applied.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-03-28 10:59:01 +02:00
Johan Hovold a794499b26 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>
2017-03-28 10:54:39 +02:00
Johan Hovold 415d7b3a54 USB: serial: add probe callback to generic driver
Add a probe callback to the generic driver and print the
only-for-testing message there.

This is a first step in getting rid of the CONFIG_USB_SERIAL_GENERIC
ifdef from usb-serial core.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-03-28 10:54:39 +02:00
Johan Hovold 07814246dd 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>
2017-03-28 10:54:39 +02:00
Johan Hovold 92e6b2c675 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>
2017-03-16 10:33:41 +01:00
Johan Hovold 8520ac0d70 USB: serial: replace runtime overflow check
Since commit 0a8fd13462 ("USB: fix problems with duplicate endpoint
addresses") USB core guarantees that there are no more than 15 endpoint
descriptors per type (and altsetting) so the corresponding overflow
checks can now be replaced with a compile-time check on the array sizes
(and indirectly the maximum number of ports).

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-03-16 10:33:41 +01:00
Johan Hovold 1546e6aecb USB: serial: refactor and clean up endpoint handling
Refactor and clean up endpoint handling.

This specifically moves the endpoint-descriptor arrays of the stack.

Note that an err_free_epds label is not yet added to avoid a compilation
warning when neither CONFIG_USB_SERIAL_PL2303 or
CONFIG_USB_SERIAL_GENERIC is selected.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-03-16 10:33:09 +01:00
Johan Hovold ef88f33fc1 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>
2017-03-16 10:13:37 +01:00
Johan Hovold c2fef4564c USB: serial: clean up probe error paths
Clean up the probe error paths by adding a couple of new error labels.

Signed-off-by: Johan Hovold <johan@kernel.org>
2017-03-16 10:13:36 +01:00
Johan Hovold 126d26f66d USB: serial: fix potential NULL-dereference at probe
Make sure we have at least one port before attempting to register a
console.

Currently, at least one driver binds to a "dummy" interface and requests
zero ports for it. Should such an interface also lack endpoints, we get
a NULL-deref during probe.

Fixes: e5b1e2062e ("USB: serial: make minor allocation dynamic")
Cc: stable <stable@vger.kernel.org>	# 3.11
Signed-off-by: Johan Hovold <johan@kernel.org>
2016-10-21 16:47:17 +02:00
Alexey Klimov 647024a7df USB: serial: fix memleak in driver-registration error path
udriver struct allocated by kzalloc() will not be freed
if usb_register() and next calls fail. This patch fixes this
by adding one more step with kfree(udriver) in error path.

Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
2016-08-08 13:41:17 +02:00
Linus Torvalds 19e36ad292 USB patches for 4.7-rc1
Here's the big pull request for USB and PHY drivers for 4.7-rc1
 
 Full details in the shortlog, but it's the normal major gadget driver
 updates, phy updates, new usbip code, as well as a bit of lots of other
 stuff.
 
 All have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB updates from Greg KH:
 "Here's the big pull request for USB and PHY drivers for 4.7-rc1

  Full details in the shortlog, but it's the normal major gadget driver
  updates, phy updates, new usbip code, as well as a bit of lots of
  other stuff.

  All have been in linux-next with no reported issues"

* tag 'usb-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (164 commits)
  USB: serial: ti_usb_3410_5052: add MOXA UPORT 11x0 support
  USB: serial: fix minor-number allocation
  USB: serial: quatech2: fix use-after-free in probe error path
  USB: serial: mxuport: fix use-after-free in probe error path
  USB: serial: keyspan: fix debug and error messages
  USB: serial: keyspan: fix URB unlink
  USB: serial: keyspan: fix use-after-free in probe error path
  USB: serial: io_edgeport: fix memory leaks in probe error path
  USB: serial: io_edgeport: fix memory leaks in attach error path
  usb: Remove unnecessary space before operator ','.
  usb: Remove unnecessary space before open square bracket.
  USB: FHCI: avoid redundant condition
  usb: host: xhci-rcar: Avoid long wait in xhci_reset()
  usb/host/fotg210: remove dead code in create_sysfs_files
  usb: wusbcore: Do not initialise statics to 0.
  usb: wusbcore: Remove space before ',' and '(' .
  USB: serial: cp210x: clean up CRTSCTS flag code
  USB: serial: cp210x: get rid of magic numbers in CRTSCTS flag code
  USB: serial: cp210x: fix hardware flow-control disable
  USB: serial: option: add even more ZTE device ids
  ...
2016-05-20 21:12:25 -07:00
Johan Hovold 194e958c5c USB: serial: fix minor-number allocation
Due to a missing upper bound, invalid minor numbers could be assigned to
ports. Such devices would later fail to register, but let's catch this
early as intended and avoid having devices with only a subset of their
ports registered (potentially the empty set).

Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-10 09:40:16 +02:00
Peter Hurley d41861ca19 tty: Replace ASYNC_INITIALIZED bit and update atomically
Replace ASYNC_INITIALIZED bit in the tty_port::flags field with
TTY_PORT_INITIALIZED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_initialized() and tty_port_initialized() to abstract
atomic bit ops.

Note: the transforms for test_and_set_bit() and test_and_clear_bit()
are unnecessary as the state transitions are already mutually exclusive;
the tty lock prevents concurrent open/close/hangup.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Javier Martinez Canillas 8c34d82e9d USB: serial: use IS_ENABLED() instead of checking for FOO || FOO_MODULE
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either
built-in or as a module, use that macro instead of open coding the same.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
2016-04-25 12:39:58 +02:00
Johannes Thumshirn d23f47d492 USB: serial: Destroy serial_minors IDR on module exit
Destroy serial_minors IDR on module exit, reclaiming the allocated memory.

This was detected by the following semantic patch (written by Luis
Rodriguez <mcgrof@suse.com>)

<SmPL>
@ defines_module_init @
declarer name module_init, module_exit;
declarer name DEFINE_IDR;
identifier init;
@@

module_init(init);

@ defines_module_exit @
identifier exit;
@@

module_exit(exit);

@ declares_idr depends on defines_module_init && defines_module_exit @
identifier idr;
@@

DEFINE_IDR(idr);

@ on_exit_calls_destroy depends on declares_idr && defines_module_exit @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 idr_destroy(&idr);
 ...
}

@ missing_module_idr_destroy depends on declares_idr && defines_module_exit && !on_exit_calls_destroy @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 +idr_destroy(&idr);
}
</SmPL>

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: stable <stable@vger.kernel.org>	# v3.11
Signed-off-by: Johan Hovold <johan@kernel.org>
2015-07-09 10:41:23 +02:00
Johan Hovold 2deb96b5d4 USB: serial: fix port attribute-creation race
Fix attribute-creation race with userspace by using the port device
groups field to create the port attributes.

Also use %u when printing the port number, which is unsigned, even
though we do not currently support more than 128 ports per device.

Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Greg Kroah-Hartman <greg@kroah.com>
2015-02-26 17:12:46 +01:00
Johan Hovold bc4b1f486f Revert "USB: serial: make bulk_out_size a lower limit"
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>
2015-02-26 17:02:15 +01:00
Johan Hovold 5654699fb3 USB: serial: fix potential heap buffer overflow
Make sure to verify the number of ports requested by subdriver to avoid
writing beyond the end of fixed-size array in interface data.

The current usb-serial implementation is limited to eight ports per
interface but failed to verify that the number of ports requested by a
subdriver (which could have been determined from device descriptors) did
not exceed this limit.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-27 13:23:52 -07:00
Johan Hovold d979e9f9ec USB: serial: fix potential stack buffer overflow
Make sure to verify the maximum number of endpoints per type to avoid
writing beyond the end of a stack-allocated array.

The current usb-serial implementation is limited to eight ports per
interface but failed to verify that the number of endpoints of a certain
type reported by a device did not exceed this limit.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-27 13:23:52 -07:00
Johan Hovold 3fff3b4343 USB: serial: remove overly defensive port tests
The only way a port pointer may be NULL is if probe() failed, and in
that case neither disconnect(), resume(), or reset_resume() will be
called.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-27 15:04:08 -07:00
Johan Hovold 10164c2ad6 USB: serial: fix sysfs-attribute removal deadlock
Fix driver new_id sysfs-attribute removal deadlock by making sure to
not hold any locks that the attribute operations grab when removing the
attribute.

Specifically, usb_serial_deregister holds the table mutex when
deregistering the driver, which includes removing the new_id attribute.
This can lead to a deadlock as writing to new_id increments the
attribute's active count before trying to grab the same mutex in
usb_serial_probe.

The deadlock can easily be triggered by inserting a sleep in
usb_serial_deregister and writing the id of an unbound device to new_id
during module unload.

As the table mutex (in this case) is used to prevent subdriver unload
during probe, it should be sufficient to only hold the lock while
manipulating the usb-serial driver list during deregister. A racing
probe will then either fail to find a matching subdriver or fail to get
the corresponding module reference.

Since v3.15-rc1 this also triggers the following lockdep warning:

======================================================
[ INFO: possible circular locking dependency detected ]
3.15.0-rc2 #123 Tainted: G        W
-------------------------------------------------------
modprobe/190 is trying to acquire lock:
 (s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94

but task is already holding lock:
 (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (table_lock){+.+.+.}:
       [<c0075f84>] __lock_acquire+0x1694/0x1ce4
       [<c0076de8>] lock_acquire+0xb4/0x154
       [<c03af3cc>] _raw_spin_lock+0x4c/0x5c
       [<c02bbc24>] usb_store_new_id+0x14c/0x1ac
       [<bf007eb4>] new_id_store+0x68/0x70 [usbserial]
       [<c025f568>] drv_attr_store+0x30/0x3c
       [<c01690e0>] sysfs_kf_write+0x5c/0x60
       [<c01682c0>] kernfs_fop_write+0xd4/0x194
       [<c010881c>] vfs_write+0xbc/0x198
       [<c0108e4c>] SyS_write+0x4c/0xa0
       [<c000f880>] ret_fast_syscall+0x0/0x48

-> #0 (s_active#4){++++.+}:
       [<c03a7a28>] print_circular_bug+0x68/0x2f8
       [<c0076218>] __lock_acquire+0x1928/0x1ce4
       [<c0076de8>] lock_acquire+0xb4/0x154
       [<c0166b70>] __kernfs_remove+0x254/0x310
       [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94
       [<c0169fb8>] remove_files.isra.1+0x48/0x84
       [<c016a2fc>] sysfs_remove_group+0x58/0xac
       [<c016a414>] sysfs_remove_groups+0x34/0x44
       [<c02623b8>] driver_remove_groups+0x1c/0x20
       [<c0260e9c>] bus_remove_driver+0x3c/0xe4
       [<c026235c>] driver_unregister+0x38/0x58
       [<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial]
       [<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial]
       [<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial]
       [<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra]
       [<c009d6cc>] SyS_delete_module+0x184/0x210
       [<c000f880>] ret_fast_syscall+0x0/0x48

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(table_lock);
                               lock(s_active#4);
                               lock(table_lock);
  lock(s_active#4);

 *** DEADLOCK ***

1 lock held by modprobe/190:
 #0:  (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial]

stack backtrace:
CPU: 0 PID: 190 Comm: modprobe Tainted: G        W     3.15.0-rc2 #123
[<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24)
[<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28)
[<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8)
[<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4)
[<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154)
[<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310)
[<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94)
[<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84)
[<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac)
[<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44)
[<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20)
[<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4)
[<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58)
[<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial])
[<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial])
[<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial])
[<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra])
[<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210)
[<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48)

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24 12:50:56 -07:00
Johan Hovold d9a38a8741 USB: serial: add missing newlines to dev_<level> messages.
Add missing newlines to dev_<level> messages.

Also make some messages less verbose where appropriate.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
2014-03-12 12:44:50 -07:00
Johan Hovold ca0400d2ca USB: serial: add missing braces
Add missing braces to conditional branches and one loop in usb-serial
core and generic implementation.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
2014-03-12 12:44:50 -07:00
Johan Hovold 5083fd7bdf 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>
2014-03-12 12:44:49 -07:00
Johan Hovold 4d5147ec90 USB: serial: clean up ioctl debugging
Remove redundant ioctl debugging from subdrivers. The ioctl request code
has already been logged by usb-serial core.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-03 12:31:46 -08:00
Johan Hovold f5f4530451 USB: serial: clean up dtr_rts
Since commit 957dacae ("TTY: fix DTR not being dropped on hang up")
dtr_rts is no longer called for uninitialised ports (e.g. after
a disconnect), which removes the need to grab the disconnect mutex.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-23 16:21:50 -07:00
Greg Kroah-Hartman 455b4f7e18 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>
2013-06-17 13:34:15 -07:00
Greg Kroah-Hartman e5b1e2062e 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>
2013-06-17 13:30:02 -07:00
Greg Kroah-Hartman 1143832eca 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(-)
2013-06-10 14:46:40 -07:00
Johan Hovold f4488035ab USB: serial: fix TIOCMIWAIT return value
Fix regression introduced by commit 143d9d9616 ("USB: serial: add
tiocmiwait subdriver operation") which made the ioctl operation return
ENODEV rather than ENOIOCTLCMD when a subdriver TIOCMIWAIT
implementation is missing.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-05 08:34:42 -07:00
Johan Hovold 4746b6c6ef USB: serial: clean up chars_in_buffer
No need to grab disconnect mutex in chars_in_buffer now that no
sub-driver is or should be querying hardware buffers anymore. (They
should use wait_until_sent.)

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-16 17:32:23 -07:00
Johan Hovold dcf0105039 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>
2013-05-16 17:32:21 -07:00
Johan Hovold 0693196fe7 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>
2013-05-16 17:32:21 -07:00
Linus Torvalds ec25e246b9 USB patches for 3.10-rc1
Here's the big USB pull request for 3.10-rc1.
 
 Lots of USB patches here, the majority being USB gadget changes and
 USB-serial driver cleanups, the rest being ARM build fixes / cleanups,
 and individual driver updates.  We also finally got some chipidea fixes,
 which have been delayed for a number of kernel releases, as the
 maintainer has now reappeared.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB patches from Greg Kroah-Hartman:
 "Here's the big USB pull request for 3.10-rc1.

  Lots of USB patches here, the majority being USB gadget changes and
  USB-serial driver cleanups, the rest being ARM build fixes / cleanups,
  and individual driver updates.  We also finally got some chipidea
  fixes, which have been delayed for a number of kernel releases, as the
  maintainer has now reappeared.

  All of these have been in linux-next for a while"

* tag 'usb-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (568 commits)
  USB: ehci-msm: USB_MSM_OTG needs USB_PHY
  USB: OHCI: avoid conflicting platform drivers
  USB: OMAP: ISP1301 needs USB_PHY
  USB: lpc32xx: ISP1301 needs USB_PHY
  USB: ftdi_sio: enable two UART ports on ST Microconnect Lite
  usb: phy: tegra: don't call into tegra-ehci directly
  usb: phy: phy core cannot yet be a module
  USB: Fix initconst in ehci driver
  usb-storage: CY7C68300A chips do not support Cypress ATACB
  USB: serial: option: Added support Olivetti Olicard 145
  USB: ftdi_sio: correct ST Micro Connect Lite PIDs
  ARM: mxs_defconfig: add CONFIG_USB_PHY
  ARM: imx_v6_v7_defconfig: add CONFIG_USB_PHY
  usb: phy: remove exported function from __init section
  usb: gadget: zero: put function instances on unbind
  usb: gadget: f_sourcesink.c: correct a copy-paste misnomer
  usb: gadget: cdc2: fix error return code in cdc_do_config()
  usb: gadget: multi: fix error return code in rndis_do_config()
  usb: gadget: f_obex: fix error return code in obex_bind()
  USB: storage: convert to use module_usb_driver()
  ...
2013-04-29 12:19:23 -07:00