Commit graph

99 commits

Author SHA1 Message Date
Alan Cox
c56d300086 usb_serial: Fix remaining ref count/lock bugs
This fixes
- locking bug that was hidden by ecc2e05e73
- Regression #13821
- Spurious warning when closing and blocking for data write out

With these changes my PL2303 always ends up as ttyUSB0 when it should and
the module refcounts stay correct.

I'll do a more wholesale split & tidy of _open in the next release or two
as we get a standard tty_port_open and port->ops->init port->ops->shutdown
call backs.

Copy sent to Alan Stern and Carlos Mafra just to confirm it fixes all the
reports but it passes local testing with the same hardware as Alan Stern.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-27 17:26:23 -07:00
Alan Cox
b68f2fb9e7 tty: Fix a USB serial crash/scribble
The port lock is used to protect the port state. However the port structure
is freed on a hangup, then the lock taken on a close. The right fix is to
drop the port on tty->shutdown() but we can't yet do that due to sleep v
non-sleeping rules. Instead do the next best thing and fix it up when we are
not in -rc season.

Reported-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Tested-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-27 12:23:22 -07:00
Linus Torvalds
51feb98d25 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (48 commits)
  USB: otg: fix module reinsert issue
  USB: handle zero-length usbfs submissions correctly
  USB: EHCI: report actual_length for iso transfers
  USB: option: remove unnecessary and erroneous code
  USB: cypress_m8: remove invalid Clear-Halt
  USB: musb_host: undo incorrect change in musb_advance_schedule()
  USB: fix LANGID=0 regression
  USB: serial: sierra driver id_table additions
  USB serial: Add ID for Turtelizer, an FT2232L-based JTAG/RS-232 adapter.
  USB: fix race leading to a write after kfree in usbfs
  USB: Sierra: fix oops upon device close
  USB: option.c: add A-Link 3GU device id
  USB: Serial: Add support for Arkham Technology adapters
  USB: Fix option_ms regression in 2.6.31-rc2
  USB: gadget audio: select SND_PCM
  USB: ftdi: support NDI devices
  Revert USB: usbfs: deprecate and hide option for !embedded
  USB: usb.h: fix kernel-doc notation
  USB: RNDIS gadget, fix issues talking from PXA
  USB: serial: FTDI with product code FB80 and vendor id 0403
  ...
2009-07-13 10:23:03 -07:00
Jason Wessel
6e40612101 USB: console: Fix regression in usb console on kernel boot
The commit 335f8514f2 introduced a
regression which stopped usb consoles from working correctly as a
kernel boot console as well as interactive login device.

The addition of the serial_close() which in turn calls
tty_port_close_start() will change the reference count of port.count
and warn about it.  The usb console code had previously incremented
the port.count to indicate it was making use of the device as a
console and the forced change causes a double open on the usb device
which leads to a non obvious kernel oops later on when the tty is
freed.

To fix the problem instead make use of port->console to track if the
port is in fact an active console port to avoid double initialization
of the usb serial device.  The port.count is incremented and
decremented only with in the scope of usb_console_setup() for the
purpose of the low level driver initialization.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-12 15:16:39 -07:00
Alexey Dobriyan
405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00
Thadeu Lima de Souza Cascardo
f4fa446883 usb_serial: Fix oops when unexisting usb serial device is opened.
This commit 335f8514f2 has stopped
properly checking if there is any usb serial associated with the tty in
the close function. It happens the close function is called by releasing
the terminal right after opening the device fails.

As an example, open fails with a non-existing device, when probe has
never been called, because the device has never been plugged. This is
common in systems with static modules and no udev.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-25 11:24:26 -07:00
Alan Stern
f9c99bb8b3 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>
2009-06-15 21:44:47 -07:00
Alan Stern
c706ebdfc8 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>
2009-06-15 21:44:47 -07:00
Alan Cox
335f8514f2 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>
2009-06-11 08:50:56 -07:00
Alan Stern
0a3c8549ea usb-serial: fix crash when sub-driver updates firmware
This patch (as1244) fixes a crash in usb-serial that occurs when a
sub-driver returns a positive value from its attach method, indicating
that new firmware was loaded and the device will disconnect and
reconnect.  The usb-serial core then skips the step of registering the
port devices; when the disconnect occurs, the attempt to unregister
the ports fails dramatically.

This problem shows up with Keyspan devices and it might affect others
as well.

When the attach method returns a positive value, the patch sets
num_ports to 0.  This tells usb_serial_disconnect() not to try
unregistering any of the ports; instead they are cleaned up by
destroy_serial().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-05-28 13:54:43 -07:00
Alan Stern
2d93148ab6 USB: serial: fix lifetime and locking problems
This patch (as1229) fixes a few lifetime and locking problems in the
usb-serial driver.  The main symptom is that an invalid kevent is
created when the serial device is unplugged while a connection is
active.

	Ports should be unregistered when device is disconnected,
	not when the parent usb_serial structure is deallocated.

	Each open file should hold a reference to the corresponding
	port structure, and the reference should be released when
	the file is closed.

	serial->disc_mutex should be acquired in serial_open(), to
	resolve the classic race between open and disconnect.

	serial_close() doesn't need to hold both serial->disc_mutex
	and port->mutex at the same time.

	Release the subdriver's module reference only after releasing
	all the other references, in case one of the release routines
	needs to invoke some code in the subdriver module.

	Replace a call to flush_scheduled_work() (which is prone to
	deadlocks) with cancel_work_sync().  Also, add a call to
	cancel_work_sync() in the disconnect routine.

	Reduce the scope of serial->disc_mutex in serial_disconnect().
	The only place it really needs to protect is where the
	"disconnected" flag is set.

This fixes the bug reported in

	http://bugs.freedesktop.org/show_bug.cgi?id=20703

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Dan Williams <dcbw@redhat.com>
Tested-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-23 14:15:26 -07:00
Alexey Dobriyan
6fd69d3cf1 proc tty: switch usb-serial to ->proc_fops
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:10 -07:00
Dave Young
e4abe6658a usb-serial: fix usb_serial_register bug when boot with nousb param
With "nousb" cmdline booting, built-in serial drivers (ie. airecable)
will trigger kernel oops.

Indeed, if nousb, usb_serial_init will failed, and the usb serial bus type
will not be registerd, then usb_serial_register call driver_register
which try to register the driver to a not registered bus.

Here add usb_disabled() check in usb_serial_register to fix it.

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24 16:20:33 -07:00
James Woodcock
331879fd6f USB: serial: refuse to open recently removed USB Serial devices
A USB-serial converter device is plugged into a system, and a process
opens it's device node.  If the device is physically removed whilst the
process still has its device node open, then other processes can
sucessfully open the now non-existent device's node.  I would expect
that open() on a device that has been physically removed should return
ENODEV.

This is manifesting itself with getty on my system.  I do the following:
1.  set up inittab to spawn getty on ttyUSB0, eg:
    T1:23:respawn:/sbin/getty -L ttyUSB0 115200 vt100
2.  Plug in USB-serial converter cable
3.  Wait for a login prompt on a terminal program attached to the serial
    cable
4.  Login
5.  Pull the USB-serial converter cable from the box
6.  getty doesn't realise that ttyUSB0 no longer exists as /dev/ttyUSB0
    can still be opened.
7.  Re-insert the USB-serial converter cable
8.  You should no longer get a login prompt over the serial cable, as
    the the USB-serial cable now shows up as /dev/ttyUSB1, and getty is
    trying to talk to /dev/ttyUSB0.

The attached patch will cause open("/dev/ttyUSB0", O_RDONLY) to return
ENODEV after the USB-serial converter has been pulled.  The patch was
created against 2.6.28.1.  I can supply it against something else if
needs be.  It is fairly simple, so should be OK.

I am using a pl2303 device, although I don't think that makes any
difference.


From: James Woodcock <James.Woodcock@ACULAB.COM>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24 16:20:31 -07:00
Oliver Neukum
1c27ae671e USB: serial: remove recourse to generic method
This removes the fallback to the generic method. It is cleaner to
explicitely request it. Introducing this was my mistake. This will
be solved by an explicit test and the driver being allowed to request
what it needs to be done upon resumption.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24 16:20:30 -07:00
Oliver Neukum
c49cfa9170 USB: serial: use generic method if no alternative is provided in usb serial layer
This patch makes use of the generic method if a serial driver provides
no implementation. This simplifies implementing suspend/resume support
in serial drivers.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24 16:20:30 -07:00
Oliver Neukum
f8bece8d91 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
2009-03-24 16:20:29 -07:00
Alan Cox
bf0672db79 usb-serial: remove NULL check
Julia Lawell found a case where a NULL check was misplaced in the
usb-serial code. However as the object in question cannot be NULL the
check can simply be removed.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-12 16:37:00 -08:00
Alan Cox
6b447f04a9 tty: Drop the lock_kernel in the private ioctl hook
We don't need the BKL here any more so it can go. In a couple of spots the
driver requirements are not clear so push the lock down into the driver.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:42 -08:00
Alan Cox
eff6937a46 tty: USB tty devices can block in tcdrain when unplugged
The underlying problem is that the device methods don't all correctly
handle disconnected status and some keep reporting bytes pending which
causes tcdrain to stall.

When the cable is unplugged they are definitely gone, and as this is true
for all USB cables we can fix it in the core usb serial code.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:40 -08:00
Alan Cox
4bd43f2c31 tty: Fix close races in USB serial
USB serial has always had races where the tty port usage count can hit zero
during a receive event. The internal locking is a mutex so we can't use
that in the IRQ handlers.

With krefs we can tackle this differently but we still need to be careful.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:37 -08:00
Alan Cox
fce4877a67 tty: Fix USB kref leak
When we close we must clear the extra reference we got when we read
port->tty. Setting the port tty NULL will clear the kref held by the driver
but not the one we obtained ourselves while doing the lookup.

Signed-off-by: Alan Cox <alan@redhat.com>
Tested-by: Helge Hafting <helge.hafting@aitel.hist.no>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-30 12:09:07 -07:00
Greg Kroah-Hartman
194343d936 USB: remove use of err() in drivers/usb/serial
err() is going away, so switch to dev_err() or printk() if it's really
needed.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-17 14:41:10 -07:00
Greg Kroah-Hartman
c197a8db59 USB: remove info() macro from usb/serial drivers
USB should not be having it's own printk macros, so remove info() and
use the system-wide standard of dev_info() wherever possible.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-17 14:41:09 -07:00
Alan Cox
4a90f09b20 tty: usb-serial krefs
Use kref in the USB serial drivers so that we don't free tty structures
from under the URB receive handlers as has historically been the case if
you were unlucky. This also gives us a framework for general tty drivers to
use tty_port objects and refcount.

Contains two err->dev_err changes merged together to fix clashes in the
-next tree.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 09:51:41 -07:00
Andreas Bombe
ce816cf9c9 usb-serial: Add Siemens EF81 to PL-2303 hack triggers
This hardware needs the pl2303 hack in order to work properly :(

Signed-off-by: Andreas Bombe <aeb@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-09-23 13:58:08 -07:00
Alan Stern
0282b7f2a8 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>
2008-08-13 17:32:50 -07:00
Alan Cox
9e98966c7b tty: rework break handling
Some hardware needs to do break handling itself and may have partial
support only. Make break_ctl return an error code. Add a tty driver flag
so you can indicate driver hardware side break support.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 13:03:28 -07:00
Alan Cox
a8d6f0a9c4 usb-serial: Coding style
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>
2008-07-22 13:03:24 -07:00
Alan Cox
95da310e66 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>
2008-07-22 13:03:22 -07:00
Oliver Neukum
62ad296b6c USB: fix usb serial pm counter decrement for disconnected interfaces
usb serial decrements the pm counter even if an interface has been
disconnected. If it was a logical disconnect the interface may belong
already to another driver. This patch introduces a check for disconnected
interfaces.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Cc: Stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 15:16:36 -07:00
Andre Haupt
dd9ca5d9be USB: usb-serial: fix a sparse warning about different signedness
fix the following sparse warning:

drivers/usb/serial/usb-serial.c:927:43: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/usb-serial.c:927:43:    expected unsigned int *minor
drivers/usb/serial/usb-serial.c:927:43:    got int *<noident>
  CHECK   drivers/usb/serial/generic.c

Signed-off-by: Andre Haupt <andre@bitwigglers.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 15:16:33 -07:00
Kay Sievers
0031a06e2f USB: usb dev_set_name() instead of dev->bus_id
The bus_id field is going away, use the dev_set_name() function
to set it properly.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 15:15:47 -07:00
Kay Sievers
7071a3ce0c USB: usb dev_name() instead of dev->bus_id
The bus_id field is going away, use the dev_name() function instead.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 15:15:46 -07:00
Alan Cox
f34d7a5b70 tty: The big operations rework
- Operations are now a shared const function block as with most other Linux
  objects

- Introduce wrappers for some optional functions to get consistent behaviour

- Wrap put_char which used to be patched by the tty layer

- Document which functions are needed/optional

- Make put_char report success/fail

- Cache the driver->ops pointer in the tty as tty->ops

- Remove various surplus lock calls we no longer need

- Remove proc_write method as noted by Alexey Dobriyan

- Introduce some missing sanity checks where certain driver/ldisc
  combinations would oops as they didn't check needed methods were present

[akpm@linux-foundation.org: fix fs/compat_ioctl.c build]
[akpm@linux-foundation.org: fix isicom]
[akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build]
[akpm@linux-foundation.org: fix kgdb]
Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:47 -07:00
Alan Cox
a5b6f60c5a usb serial: more fixes and groundwork for tty changes
- If a termios change fails due to lack of memory we should copy the
   old settings back over as the device has not changed
 - Note various locking problems
 - kl5kusb105 had various remaining tty flag handling problems
 - Make safe_serial use tty_insert_flip_string not open coded loops
 - set termios speed properly in usb_serial

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:55 -07:00
Harvey Harrison
441b62c1ed USB: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:55 -07:00
Greg Kroah-Hartman
9aebfd6bda 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>
2008-04-24 21:16:52 -07:00
Alan Cox
2097890c43 USB: usb-serial: Prepare for BKL push down
Take the lock in usb-serial instead. As it relies on the BKL internally
we can't push it any deeper yet.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:38 -07:00
Greg Kroah-Hartman
07c3b1a100 USB: remove broken usb-serial num_endpoints check
The num_interrupt_in, num_bulk_in, and other checks in the usb-serial
code are just wrong, there are too many different devices out there with
different numbers of endpoints.  We need to just be sticking with the
device ids instead of trying to catch this kind of thing.  It broke too
many different devices.

This fixes a large number of usb-serial devices to get them working
properly again.


Cc: Oliver Neukum <oliver@neukum.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-15 22:30:53 -07:00
Oliver Neukum
a1cd7e99b3 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>
2008-02-01 14:35:03 -08:00
Sarah Sharp
f0fbd5b9ba USB: Prepare serial core for autosuspend.
Claim the interface for a USB to serial converter when the tty is open,
and release the interface when the tty is closed.

If a driver doesn't provide a resume function, use the generic resume
instead.

Make sure the generic resume function does not submit the URBs if we're
coming back from autosuspend.  On autoresume, we know that the open
function will be called next, which will attempt to submit the URBs.  If
we submit them in the resume function, the open will fail.

This works for:
 - autosuspend
 - suspending with the tty open or closed
 - hibernate with the tty closed

A hibernate (or a suspend that causes the USB subsystem to lose power)
has issues.  If you have the tty open when you hibernate, a new tty will
be created when the device re-enumerates during resume.

Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 14:34:51 -08:00
Aristeu Rozanski
9a6b1efa6f 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>
2008-02-01 14:34:50 -08:00
Sarah Sharp
8abaee238e USB: usb_serial_resume bug fix
Avoid potential null pointer dereference.

Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-25 12:18:45 -07:00
Alan Cox
337850917a usb-serial: handle NULL termios methods as "no hardware changing support"
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-25 12:18:42 -07:00
Alan Stern
063a2da8f0 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>
2007-10-12 14:55:34 -07:00
Oliver Neukum
5adceac5da USB: fix errornous assumption in the usb serial framework revealed by iuu_phoenix
the iuu_phoenix driver submits another URB from a completion handler.
This dictates a certain order of calls to usb_kill_urb() in kill_traffic().
As other drivers may do it the other way round, we need to use both
orders in kill_traffic().
This patch does so and should be merged before iuu_phoenix is merged.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:25 -07:00
Oliver Neukum
3ddad8232c USB: fix BUG: sleeping function called from invalid context at /home/jeremy/hg/xen/paravirt/linux/drivers/usb/core/urb.c:524, in_atomic():1, irqs_disabled():0
Clearly there's a bug in
drivers/usb/serial/usb-serial.c:usb_serial_put().  It shouldn't call
kref_put() while holding a spinlock.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-30 13:27:46 -07:00
Oliver Neukum
e31c18804f USB: fix usb_serial_suspend(): buggy code
Am Montag 23 Juli 2007 schrieb Adrian Bunk:
> Commit ec22559e0b added the following 
> function to drivers/usb/serial/usb-serial.c:
> 
[..]
> 
> The Coverity checker spotted the inconsequent NULL checking for "serial".
> 
> Looking at the code it also doesn't seem to have been intended to always 
> return 0.

Coverity is right. The check for NULL is wrongly done and the error
return is lost.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-30 13:27:45 -07:00
Benny Halevy
52f6b5e1f1 synchronization in usb_serial_put
I think there is a race between usb_serial_put() and
usb_serial_get_by_index() (and get_free_serial()) with regards
to handling the serial port refcount.

usb_serial_get_by_index() gets a reference on the serial port under
table_lock while return_serial releases all the returned ports
from the table under the same lock.  However, the table_lock is not
taken around the call to kref_put, theoretically allowing to sneak
in and grab a reference after kref_put has already determined that
the reference count is zero (and before calling destroy_serial)
causing use after free.

Signed-off-by: Benny Halevy <bhalevy@ns1.bhalevy.com>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-12 16:34:31 -07:00