summaryrefslogtreecommitdiff
path: root/drivers/usb/gadget/u_serial.c
AgeCommit message (Collapse)Author
2010-11-11usb: subtle increased memory usage in u_serialJim Sung
OK, the USB gadget serial driver actually has a couple of problems. On gs_open(), it always allocates and queues an additional QUEUE_SIZE (16) worth of requests, so with a loop like this: i=1 ; while echo $i > /dev/ttyGS0 ; do let i++ ; done eventually we run into OOM (Out of Memory). Technically, it is not a leak as everything gets freed up when the USB connection is broken, but not on gs_close(). With a USB device/gadget controller driver that has limited resources (e.g., Marvell has a this MAX_XDS_FOR_TR_CALLS of 64 for transmit and receive), so even after 4 stty -F /dev/ttyGS0 we cannot transmit anymore. We can still receive (not necessarily reliably) as now we have 16 * 4 = 64 descriptors/buffers ready, but the device is otherwise not usable. Signed-off-by: Jim Sung <jsung@syncadence.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10USB: gadget: compilation issue: missing TASK_INTERRUPTIBLEstephane duverger
Here is the patch for the following issue: drivers/usb/gadget/u_serial.c: In function ‘gs_start_tx’: drivers/usb/gadget/u_serial.c:369: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function) drivers/usb/gadget/u_serial.c:369: error: (Each undeclared identifier is reported only once drivers/usb/gadget/u_serial.c:369: error: for each function it appears in.) drivers/usb/gadget/u_serial.c: In function ‘gs_rx_push’: drivers/usb/gadget/u_serial.c:546: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function) drivers/usb/gadget/u_serial.c: In function ‘gs_close’: drivers/usb/gadget/u_serial.c:857: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function) drivers/usb/gadget/u_serial.c:857: error: implicit declaration of function ‘signal_pending’ drivers/usb/gadget/u_serial.c:857: error: implicit declaration of function ‘schedule_timeout’ drivers/usb/gadget/u_serial.c: In function ‘gserial_cleanup’: drivers/usb/gadget/u_serial.c:1190: error: ‘TASK_UNINTERRUPTIBLE’ undeclared (first use in this function) drivers/usb/gadget/u_serial.c:1190: error: implicit declaration of function ‘schedule’ drivers/usb/gadget/u_serial.c: In function ‘gserial_disconnect’: drivers/usb/gadget/u_serial.c:1311: error: ‘TASK_INTERRUPTIBLE’ undeclared (first use in this function) Signed-off-by: Stephane Duverger <stephane.duverger@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-30USB: g_serial: fix tty cleanup on unloadJon Povey
Call put_tty_driver() in cleanup function, to fix Oops when trying to open gadget serial char device after module unload. Signed-off-by: Jon Povey <jon.povey@racelogic.co.uk> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-30USB: g_serial: don't set low_latency flagJon Povey
No longer set low_latency flag as it causes this warning backtrace: WARNING: at kernel/mutex.c:207 __mutex_lock_slowpath+0x6c/0x288() Fix associated locking and wakeups. Signed-off-by: Jon Povey <jon.povey@racelogic.co.uk> Cc: Maulik Mankad <x0082077@ti.com> Cc: stable <stable@kernel.org> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-09-23USB: double put_tty_driver(gs_tty_driver) in gserial_setup()Roel Kluin
If the driver cannot be registered, put_tty_driver(gs_tty_driver) occurred here as well as at label fail. put_tty_driver() already occurs at label fail Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-16USB: gadget: g_serial: append zlp when tx buffer becomes emptyDaniel Glöckner
Some usb serial host drivers expect a short packet before they forward the data to the application. This is caused by them trying to read more than one packet at a time. So when the gadget sends an exact multiple of the maximum packet size, it should append a zero-length packet. Signed-off-by: Daniel Glöckner <dg@emlix.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24USB: replace uses of __constant_{endian}Harvey Harrison
The base versions handle constant folding now. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-14usb gadget: issue notifications from ACM functionDavid Brownell
Update the CDC-ACM gadget code to support the peripheral-to-host notifications when the tty is opened or closed, or issues a BREAK. The serial framework code calls new generic hooks; right now only CDC-ACM uses those hooks. This resolves several REVISIT comments in the code. (Based on a patch from Felipe Balbi.) Note that this doesn't expose USB_CDC_CAP_BRK to the host, since this code still rejects USB_CDC_REQ_SEND_BREAK control requests for host-to-peripheral BREAK signaling (received via /dev/ttyGS*). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Felipe Balbi <felipe.balbi@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-14USB: serial gadget: rx path data loss fixesDavid Brownell
Update RX path handling in new serial gadget code to cope better with RX blockage: queue every RX packet until its contents can safely be passed up to the ldisc. Most of the RX path work is now done in the RX tasklet, instead of just the final "push to ldisc" step. This addresses some cases of data loss: - A longstanding serial gadget bug: when tty_insert_flip_string() didn't copy the entire buffer, the rest of the characters were dropped! Now that packet stays queued until the rest of its data is pushed to the ldisc. - Another longstanding issue: in the unlikely case that an RX transfer returns data and also reports a fault, that data is no longer discarded. - In the recently added RX throttling logic: it needs to stop pushing data into the TTY layer, instead of just not submitting new USB read requests. When the TTY is throttled long enough, backpressure will eventually make the OUT endpoint NAK. Also: an #ifdef is removed (no longer necessary); and start switching to a better convention for debug messages (prefix them with tty name). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21usb_gadget: composite cdc gadget fault handlingDavid Brownell
These two fixes ensure the new "CDC Composite Device" gadget fails cleanly when it's loaded on hardware that can't support this particular gadget driver. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21usb gadget: split out serial coreDavid Brownell
This abstracts the "gadget serial" driver TTY glue into a separate component, cleaning it up and disentangling it from connection state. It also changed some behaviors for the better: - Stops using "experimental" major #127, and switches over to having the TTY layer allocate the dev_t numbers. - Provides /sys/class/tty/ttyGS* nodes, thus mdev/udev support. (Note "mdev" hotplug bug in Busybox v1.7.2: /dev/ttyGS0 will be a *block* device without CONFIG_SYSFS_DEPRECATED_V2.) - The tty nodes no longer reject opens when there's no host. Now they can support normal getty configs in /etc/inttab... - Now implements RX throttling. When the line discipline says it doesn't want any more data, only packets in flight will be delivered (currently, max 1K/8K at full/high speeds) until it unthrottles the data. - Supports low_latency. This is a good policy for all USB serial adapters, since it eliminates scheduler overhead on RX paths. This also includes much cleanup including better comments, fixing memory leaks and other bugs (including some locking fixes), messaging cleanup, and an interface audit and tightening. This added up to a significant object code shrinkage, on the order of 20% (!) depending on CPU and compiler. A separate patch actually kicks in this new code, using the functions declared in this new header, and removes the previous glue. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>