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* Fix usb_serial_probe() problem introduced by the recent kfifo changesStefani Seibold2009-12-231-3/+2
| | | | | | | | | | | | | | | 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>
* kfifo: move out spinlockStefani Seibold2009-12-221-2/+1
| | | | | | | | | | | | | | | Move the pointer to the spinlock out of struct kfifo. Most users in tree do not actually use a spinlock, so the few exceptions now have to call kfifo_{get,put}_locked, which takes an extra argument to a spinlock. Signed-off-by: Stefani Seibold <stefani@seibold.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kfifo: move struct kfifo in placeStefani Seibold2009-12-221-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a new generic kernel FIFO implementation. The current kernel fifo API is not very widely used, because it has to many constrains. Only 17 files in the current 2.6.31-rc5 used it. FIFO's are like list's a very basic thing and a kfifo API which handles the most use case would save a lot of development time and memory resources. I think this are the reasons why kfifo is not in use: - The API is to simple, important functions are missing - A fifo can be only allocated dynamically - There is a requirement of a spinlock whether you need it or not - There is no support for data records inside a fifo So I decided to extend the kfifo in a more generic way without blowing up the API to much. The new API has the following benefits: - Generic usage: For kernel internal use and/or device driver. - Provide an API for the most use case. - Slim API: The whole API provides 25 functions. - Linux style habit. - DECLARE_KFIFO, DEFINE_KFIFO and INIT_KFIFO Macros - Direct copy_to_user from the fifo and copy_from_user into the fifo. - The kfifo itself is an in place member of the using data structure, this save an indirection access and does not waste the kernel allocator. - Lockless access: if only one reader and one writer is active on the fifo, which is the common use case, no additional locking is necessary. - Remove spinlock - give the user the freedom of choice what kind of locking to use if one is required. - Ability to handle records. Three type of records are supported: - Variable length records between 0-255 bytes, with a record size field of 1 bytes. - Variable length records between 0-65535 bytes, with a record size field of 2 bytes. - Fixed size records, which no record size field. - Preserve memory resource. - Performance! - Easy to use! This patch: Since most users want to have the kfifo as part of another object, reorganize the code to allow including struct kfifo in another data structure. This requires changing the kfifo_alloc and kfifo_init prototypes so that we pass an existing kfifo pointer into them. This patch changes the implementation and all existing users. [akpm@linux-foundation.org: fix warning] Signed-off-by: Stefani Seibold <stefani@seibold.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* usb_serial: Kill port mutexAlan Cox2009-12-111-1/+0
| | | | | | | | | | | 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: Use the shutdown() operationAlan Cox2009-12-111-28/+11
| | | | | | | | | | | | | | As Alan Stern pointed out - now we have tty_port_open the shutdown method and locking allow us to whack the other bits into the full helper methods and provide a shutdown op which the tty port code will synchronize with setup for us. 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>
* tty_port: add "tty_port_open" helperAlan Cox2009-12-111-29/+20
| | | | | | | | | | | | For the moment this just moves the USB logic over and fixes the 'what if we open and hangup at the same time' race noticed by Oliver Neukum. 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: small fix in error case of suspend in generic usbserial codeOliver Neukum2009-10-091-1/+3
| | | | | | | | | | | usb:usbserial: fix flags in error case of suspension suspended flag must be reset in error case Signed-off-by: Oliver Neukum <oliver@neukum.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: serial: don't call release without attachAlan Stern2009-10-091-1/+5
| | | | | | | | | | | | | | | | | 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>
* tty: Fix regressions caused by commit b50989dcDave Young2009-09-271-8/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following commit made console open fails while booting: commit b50989dc444599c8b21edc23536fc305f4e9b7d5 Author: Alan Cox <alan@linux.intel.com> Date: Sat Sep 19 13:13:22 2009 -0700 tty: make the kref destructor occur asynchronously Due to tty release routines run in a workqueue now, error like the following will be reported while booting: INIT open /dev/console Input/output error It also causes hibernation regression to appear as reported at http://bugzilla.kernel.org/show_bug.cgi?id=14229 The reason is that now there's latency issue with closing, but when we open a "closing not finished" tty, -EIO will be returned. Fix it as per the following Alan's suggestion: Fun but it's actually not a bug and the fix is wrong in itself as the port may be closing but not yet being destructed, in which case it seems to do the wrong thing. Opening a tty that is closing (and could be closing for long periods) is supposed to return -EIO. I suspect a better way to deal with this and keep the old console timing is to split tty->shutdown into two functions. tty->shutdown() - called synchronously just before we dump the tty onto the waitqueue for destruction tty->cleanup() - called when the destructor runs. We would then do the shutdown part which can occur in IRQ context fine, before queueing the rest of the release (from tty->magic = 0 ... the end) to occur asynchronously The USB update in -next would then need a call like if (tty->cleanup) tty->cleanup(tty); at the top of the async function and the USB shutdown to be split between shutdown and cleanup as the USB resource cleanup and final tidy cannot occur synchronously as it needs to sleep. In other words the logic becomes final kref put make object unfindable async clean it up Signed-off-by: Dave Young <hidave.darkstar@gmail.com> [ rjw: Rebased on top of 2.6.31-git, reworked the changelog. ] Signed-off-by: "Rafael J. Wysocki" <rjw@sisk.pl> [ Changed serial naming to match new rules, dropped tty_shutdown as per comments from Alan Stern - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* USB: use kfifo to buffer usb-generic serial writesDavid VomLehn2009-09-231-0/+7
| | | | | | | | | | | | | | | | | | 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>
* USB: fix wrong order of events in usb serial suspensionOliver Neukum2009-09-231-3/+7
| | | | | | | | | | if a subdriver has an additional suspend method, it must be called first to allow the subdriver to return -EBUSY, because the second half cannot be easily undone. Signed-off-by: Oliver Neukum <oliver@neukum.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: usb-serial, remove unused variablesJiri Slaby2009-09-231-6/+0
| | | | | | | | There are some unused variables in serial_do_down. Remove them. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* usb-serial: straighten out serial_openAlan Stern2009-09-191-37/+22
| | | | | | | | | | | | | | | This patch (as1291) removes a bunch of code from serial_open(), things that were rendered unnecessary by earlier patches. A missing spinlock is added to protect port->port.count, which needs to be incremented even if the open fails but not if the tty has gotten a hangup. The test for whether the hardware has been initialized, based on the use count, is replaced by a more transparent test of the ASYNCB_INITIALIZED bit in the port flags. 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: add missing tests and debug linesAlan Stern2009-09-191-4/+17
| | | | | | | | | | | | | | | This patch (as1290) adds some missing tests. serial_down() isn't supposed to do anything if the hardware hasn't been initialized, and serial_close() isn't supposed to do anything if the tty has gotten a hangup (because serial_hangup() takes care of shutting down the hardware). The patch also updates and adds a few debugging lines. 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: rename subroutinesAlan Stern2009-09-191-8/+11
| | | | | | | | | | | This patch (as1289) renames serial_do_down() to serial_down() and serial_do_free() to serial_release(). It also adds a missing call to tty_shutdown() in serial_release(). 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: fix termios initialization logicAlan Stern2009-09-191-12/+10
| | | | | | | | | | | | This patch (as1288) fixes the initialization logic in serial_install(). A new tty always needs to have a termios initialized no matter what, not just in the case where the lower driver will override the termios settings. 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: acquire references when a new tty is installedAlan Stern2009-09-191-64/+47
| | | | | | | | | | | | | | | | | This patch (as1287) makes serial_install() be reponsible for acquiring references to the usb_serial structure and the driver module when a tty is first used. This is more sensible than having serial_open() do it, because a tty can be opened many times whereas it is installed only once, when it is created. (Not to mention that these actions are reversed when the tty is released, not when it is closed.) Finally, it is at install time that the TTY core takes its own reference to the usb_serial module, so it is only fitting that we should act the same way in regard to the lower-level serial driver. 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: change logic of serial lookupsAlan Stern2009-09-191-8/+23
| | | | | | | | | | | | | | | | | | | | | | | | | This patch (as1286) changes usb_serial_get_by_index(). Now the routine will check whether the serial device has been disconnected; if it has then the return value will be NULL. If the device hasn't been disconnected then the routine will return with serial->disc_mutex held, so that the caller can use the structure without fear of racing against driver unloads. This permits the scope of table_mutex in destroy_serial() to be reduced. Instead of protecting the entire function, it suffices to protect the part that actually uses serial_table[], i.e., the call to return_serial(). There's no longer any danger of the refcount being incremented after it reaches 0 (which was the reason for having the large scope previously), because it can't reach 0 until the serial device has been disconnected. Also, the patch makes serial_install() check that serial is non-NULL before attempting to use it. 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: put subroutines in logical orderAlan Stern2009-09-191-77/+77
| | | | | | | | | | | | This patch (as1285) rearranges the subroutines in usb-serial.c concerned with tty lifetimes into a more logical order: install, open, hangup, close, release. It also updates the formatting of the kerneldoc comments. 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: change referencing of port and serial structuresAlan Stern2009-09-191-75/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch (as1284) changes the referencing of the usb_serial and usb_serial_port structures in usb-serial.c. It's not feasible to make the port structures keep a reference to the serial structure, because the ports need to remain in existence when serial is released -- quite a few of the drivers expect this. Consequently taking a reference to the port when the device file is open is insufficient; such a reference would not pin serial. To fix this, we now take a reference to serial when the device file is opened. The final put_device() for the ports occurs in destroy_serial(), so that the ports will last as long as they are needed. The patch initializes all the port devices, including those in the unused "fake" ports. This makes the code more uniform because they can all be released in the same way. The error handling code in usb_serial_probe() is much simplified by this approach; instead of freeing everything by hand we can use a single usb_serial_put() call. Also simplified is the port-release mechanism. Instead of being two separate routines, port_release() and port_free() can be combined into one. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* tty: USB serial termios bitsAlan Cox2009-09-191-1/+37
| | | | | | | | | 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 driversAlan Cox2009-09-191-1/+1
| | | | | | | | 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: USB can now use the shutdown method for kref based freeing of portsAlan Cox2009-09-191-21/+7
| | | | | | Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* tty: USB hangup is racyAlan Cox2009-09-191-4/+1
| | | | | | | | | | | The USB layer uses tty_hangup to deal with unplugs of the physical hardware (analogous to loss of carrier) and then frees the resources. However the tty_hangup is asynchronous. As the hangup can sleep we can use tty_vhangup which is the non async version to avoid freeing resources too early. Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* usb_serial: Fix remaining ref count/lock bugsAlan Cox2009-07-271-4/+13
| | | | | | | | | | | | | | | | | | | | This fixes - locking bug that was hidden by ecc2e05e739c30870c8e4f252b63a0c4041f2724 - 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>
* tty: Fix a USB serial crash/scribbleAlan Cox2009-07-271-1/+18
| | | | | | | | | | | | | 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>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6Linus Torvalds2009-07-131-1/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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 ...
| * USB: console: Fix regression in usb console on kernel bootJason Wessel2009-07-121-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit 335f8514f200e63d689113d29cb7253a5c282967 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>
* | headers: smp_lock.h reduxAlexey Dobriyan2009-07-121-0/+1
|/ | | | | | | | | | | | | * 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>
* usb_serial: Fix oops when unexisting usb serial device is opened.Thadeu Lima de Souza Cascardo2009-06-251-0/+3
| | | | | | | | | | | | | | | This commit 335f8514f200e63d689113d29cb7253a5c282967 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>
* USB: usb-serial: replace shutdown with disconnect, releaseAlan Stern2009-06-151-16/+13
| | | | | | | | | | | | | | | | 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 timesAlan Stern2009-06-151-2/+22
| | | | | | | | | | | 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>
* tty: Bring the usb tty port structure into more useAlan Cox2009-06-111-44/+100
| | | | | | | | | | 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>
* usb-serial: fix crash when sub-driver updates firmwareAlan Stern2009-05-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* USB: serial: fix lifetime and locking problemsAlan Stern2009-04-231-36/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* proc tty: switch usb-serial to ->proc_fopsAlexey Dobriyan2009-04-011-31/+27
| | | | | | | 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>
* usb-serial: fix usb_serial_register bug when boot with nousb paramDave Young2009-03-241-0/+3
| | | | | | | | | | | | | | | 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>
* USB: serial: refuse to open recently removed USB Serial devicesJames Woodcock2009-03-241-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* USB: serial: remove recourse to generic methodOliver Neukum2009-03-241-1/+0
| | | | | | | | | | | 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>
* USB: serial: use generic method if no alternative is provided in usb serial ↵Oliver Neukum2009-03-241-2/+5
| | | | | | | | | | | | 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>
* USB: serial: introduce a flag into the usb serial layer to tell drivers that ↵Oliver Neukum2009-03-241-0/+4
| | | | | | | | | | | | | | | | | | 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-serial: remove NULL checkAlan Cox2009-01-121-3/+0
| | | | | | | | | 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>
* tty: Drop the lock_kernel in the private ioctl hookAlan Cox2009-01-021-6/+1
| | | | | | | | 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>
* tty: USB tty devices can block in tcdrain when unpluggedAlan Cox2009-01-021-0/+4
| | | | | | | | | | | | 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>
* tty: Fix close races in USB serialAlan Cox2009-01-021-5/+10
| | | | | | | | | | | 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>
* tty: Fix USB kref leakAlan Cox2008-10-301-0/+1
| | | | | | | | | | 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>
* USB: remove use of err() in drivers/usb/serialGreg Kroah-Hartman2008-10-171-7/+12
| | | | | | | | | 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>
* USB: remove info() macro from usb/serial driversGreg Kroah-Hartman2008-10-171-3/+4
| | | | | | | 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>
* tty: usb-serial krefsAlan Cox2008-10-131-9/+15
| | | | | | | | | | | | | 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>
* usb-serial: Add Siemens EF81 to PL-2303 hack triggersAndreas Bombe2008-09-231-1/+3
| | | | | | | | 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>
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