Do not decrement resp_count if it's already 0.
We set resp_count to 0 when the device is closed. The next open and
read will try to clear the WDM_READ flag if there was leftover data
in the read buffer. This fix is necessary to prevent resubmitting
the read URB in a tight loop because resp_count becomes negative.
The bug can easily be triggered from userspace by not reading all
data in the read buffer, and then closing and reopening the chardev.
Fixes: 8dd5cd5395 ("usb: cdc-wdm: avoid hanging on zero length reads")
Cc: <stable@vger.kernel.org> # 3.13
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 73e06865ea ("USB: cdc-wdm: support back-to-back
USB_CDC_NOTIFY_RESPONSE_AVAILABLE notifications") implemented
queued response handling. This added a new requirement: The read
urb must be resubmitted every time we clear the WDM_READ flag if
the response counter indicates that the device is waiting for a
read.
Fix by factoring out the code handling the WMD_READ clearing and
possible urb submission, calling it everywhere we clear the flag.
Without this fix, the driver ends up in a state where the read urb
is inactive, but the response counter is positive after a zero
length read. This prevents the read urb from ever being submitted
again and the driver appears to be hanging.
Fixes: 73e06865ea ("USB: cdc-wdm: support back-to-back USB_CDC_NOTIFY_RESPONSE_AVAILABLE notifications")
Cc: Greg Suarez <gsuarez@smithmicro.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Cc: stable <stable@vger.kernel.org> # 3.13
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
An ioctl that does depends on communication with a device should
prevent suspension of teh device.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Simple straightforward implementation. Just returning the statistics
gathered for TIOCMIWAIT
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This implements TIOCMIWAIT for TIOCM_DSR, TIOCM_RI and TIOCM_CD
Disconnect is handled as TIOCM_CD or an error.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The only notification supported by the Device Management class is
Response Available. But this driver is also used as a subdriver of
other CDC classes, allowing notifications like Speed Change and
Network Connection. This results in log messages which are only
confusing to an end user:
[66255.801874] cdc_mbim 1-3:1.5: unknown notification 42 received: index 5 len 8
These drivers use cdc-wdm as a subdriver to allow access to an
embedded management protocol, and all management is expected to
use this protocol. There is therefore no need to handle any of
these optional CDC notifications. Instead we can let the cdc-wdm
driver recognize them and log a debug level message instead of an
error.
Reported-by: Rob Gardner <robmatic@gmail.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some MBIM devices send back-to-back USB_CDC_NOTIFY_RESPONSE_AVAILABLE notifications
when sending a message over multiple fragments or when there are unsolicited
messages available.
Count up the number of USB_CDC_NOTIFY_RESPONSE_AVAILABLE notifications received
and decrement the count and submit the urb for the next response each time userspace
completes a read the response.
Signed-off-by: Greg Suarez <gsuarez@smithmicro.com>
Acked-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In auditing the usbtmc sysfs files, a bunch of them were being created
as "read only", yet they have logic to handle writing to. So fix them
up by setting the permissions properly.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Both could want to submit the same URB. Some checks of the flag
intended to prevent that were missing.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix probe of Rigol devices on big-endian machines. A quirk for these
devices was introduced by commit c2e314835 ("USB: usbtmc: Set
rigol_quirk if device is listed") but was only enabled on little-endian
machines.
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kfree(data) will be called implicitly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a few cases where braces are not needed. This patch removes
unnecessary '& 255' pieces as well when lvalue type is u8.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Recent patch series introduces few trailing spaces. This patch removes them.
No functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bInterval must be on the range 1 - 16, if we
want to pass the maximum allowed, we should
be passing 16
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When writing data we were:
lock
do some work
unlock
call function
lock
do some work
unlock
return
return
It turns out, that "function" was only ever called in the one place, so
instead of locking/unlocking for no good reason, just inline the
function and only grab the lock once.
This has sped up the pathological case of sending 1 byte packets to a
loop-back cdc-acm device from 49600 bytes per second to 50100 bytes a
second on my workstation. A tiny increase yes, but noticable, and now
the spinlock isn't the hottest thing on the perf graph anymore. Yes, we
are still waiting for the hardware for the most part, but getting rid of
a spinlock_irq_save() call for every packet is still a good thing.
And we end up deleting lines of code, always a win overall.
This was found by using a Teensy 3.0 device and the test program and
firmware located at:
http://www.pjrc.com/teensy/benchmark_usb_serial_receive.html
Reported-by: Paul Stoffregen <paul@pjrc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These patches implement a modification of the USBTMC
protocol to allow operation with Rigol equipment. Cosmetic change to show
that 12 is the USBTMC header size.
Signed-off-by: Alexandre Peixoto Ferreira <alexandref75@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These patches implement a modification of the USBTMC
protocol to allow operation with Rigol equipment. The usbtmc_read function is
modified so if the quirk is active, the TMC header is sent with the size of
the data as the whole size of the request. If the quirk is inactive, the TMC
request is sent once per bulk transfer and with size limited to the bulk
transfer size. In the case of the quirk, only the first response contains the
TMC header and the others are just data.
Signed-off-by: Alexandre Peixoto Ferreira <alexandref75@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These patches implement a modification of the USBTMC
protocol to allow operation with Rigol equipment. It an idVendor and
idProduct is found on the usbtmc_id_quirk array, the rigol_quirk is set for
this device.
Signed-off-by: Alexandre Peixoto Ferreira <alexandref75@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These patches implement a modification of the USBTMC
protocol to allow operation with Rigol equipment. The TMC request portion of
the code in function usbtmc_read is segregated to a function
send_request_dev_dep_msg_in as implemented by tommie in
https://github.com/tommie/linux/blob/usbtmc-rigol/drivers/usb/class/usbtmc.c
allowing the reuse later.
Signed-off-by: Alexandre Peixoto Ferreira <alexandref75@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These patches implement a modification of the USBTMC
protocol to allow operation with Rigol equipment. Rigol requires that a
single TMC request to receive any buffer size and bulk requests to get the
data. The original algorithm sends a TMC request for each subset of the data
(a single USB transaction). The modification is only active for Rigol
equipment, vendor and product set is contained in the array usbtmc_id_quirk.
This patch creates the rigol_quirk variable and the arrays for the
idvendor and idproduct.
Signed-off-by: Alexandre Peixoto Ferreira <alexandref75@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull input updates from Dmitry Torokhov:
"Assorted fixes and cleanups to the existing drivers plus a new driver
for IMS Passenger Control Unit device they use for ther in-flight
entertainment system."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (44 commits)
Input: trackpoint - Optimize trackpoint init to use power-on reset
Input: apbps2 - convert to devm_ioremap_resource()
Input: ALPS - use %ph to print buffers
ARM - shmobile: Armadillo800EVA: Move st1232 reset pin handling
Input: st1232 - add reset pin handling
Input: st1232 - convert to devm_* infrastructure
Input: MT - handle semi-mt devices in core
Input: adxl34x - use spi_get_drvdata()
Input: ad7877 - use spi_get_drvdata() and spi_set_drvdata()
Input: ads7846 - use spi_get_drvdata() and spi_set_drvdata()
Input: ims-pcu - fix a memory leak on error
Input: sysrq - supplement reset sequence with timeout functionality
Input: tegra-kbc - support for defining row/columns based on SoC
Input: imx_keypad - switch to using managed resources
Input: arc_ps2 - add support for device tree
Input: mma8450 - fix signed 12bits to 32bits conversion
Input: eeti_ts - remove redundant null check
Input: edt-ft5x06 - remove redundant null check before kfree
Input: ad714x - add CONFIG_PM_SLEEP to suspend/resume functions
Input: adxl34x - add CONFIG_PM_SLEEP to suspend/resume functions
...
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()
...
Inside usbtmc_ioctl_clear_out_halt()/usbtmc_ioctl_clear_in_halt(),
usb_clear_halt() needn't any buffer to pass in, so remove the
unnecessary memory allocation.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch removes the depends on USB from all config symbols in
drivers/usb/host/Kconfig and replace that with an if USB / endif block
as suggested by Alan Stern. Some source ... Kconfig lines have been
shuffled around to permit a better regroupment of the Kconfig files
depending on "config USB" item. No functionnal change is introduced.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Userspace applications need to know the maximum supported message
size.
The cdc-wdm driver translates between a character device stream
and a message based protocol. Each message is transported as a
usb control message with no further encapsulation or syncronization.
Each read or write on the character device should translate to
exactly one usb control message to ensure that message boundaries
are kept intact. That means that the userspace application must
know the maximum message size supported by the device and driver,
making this size a vital part of the cdc-wdm character device API.
CDC WDM and CDC MBIM functions export the maximum supported
message size through CDC functional descriptors. The cdc-wdm and
cdc_mbim drivers will parse these descriptors and use the value
chosen by the device. The only current way for a userspace
application to retrive the value is by duplicating the descriptor
parsing. This is an unnecessary complex task, and application
writers are likely to postpone it, using a fixed value and adding
a "todo" item.
QMI functions have no way to tell the host what message size they
support. The qmi_wwan driver use a fixed value based on protocol
recommendations and observed device behaviour. Userspace
applications must know and hard code the same value. This scheme
will break if we ever encounter a QMI device needing a device
specific message size quirk. We are currently unable to support
such a device because using a non default size would break the
implicit userspace API.
The message size is currently a hidden attribute of the cdc-wdm
userspace API. Retrieving it is unnecessarily complex, increasing
the possibility of drivers and applications using different limits.
The resulting errors are hard to debug, and can only be replicated
on identical hardware.
Exporting the maximum message size from the driver simplifies the
task for the userspace application, and creates a unified
information source independent of device and function class. It also
serves to document that the message size is part of the cdc-wdm
userspace API.
This proposed API extension has been presented for the authors of
userspace applications and libraries using the current API: libmbim,
libqmi, uqmi, oFono and ModemManager. The replies were:
Aleksander Morgado:
"We do really need max message size for MBIM; and as you say, it may be
good to have the max message size info also for QMI, so the new ioctl
seems a good addition. So +1 from my side, for what it's worth."
Dan Williams:
"Yeah, +1 here. I'd prefer the sysfs file, but the fact that that
doesn't work for fd passing pretty much kills it."
No negative replies are so far received.
Cc: Aleksander Morgado <aleksander@lanedo.com>
Cc: Dan Williams <dcbw@redhat.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Acked-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Unregister tty device in disconnect as is required by the USB stack.
By deferring unregistration to when the last tty reference is dropped,
the parent interface device can get unregistered before the child
resulting in broken hotplug events being generated when the tty is
finally closed:
KERNEL[2290.798128] remove /devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:3.1 (usb)
KERNEL[2290.804589] remove /devices/pci0000:00/0000:00:1d.7/usb2/2-1 (usb)
KERNEL[2294.554799] remove /2-1:3.1/tty/ttyACM0 (tty)
The driver must deal with tty callbacks after disconnect by checking the
disconnected flag. Specifically, further opens must be prevented and
this is already implemented.
Cc: stable <stable@vger.kernel.org>
Cc: Oliver Neukum <oneukum@suse.de>
Acked-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
acm_probe() ignores errors in tty_port_register_device()
and leaves intfdata pointing to freed memory on alloc_fail7
error path. The patch fixes the both issues.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is to pick up the fixes in that branch, and let Alan fix the merge
error in drivers/usb/host/ehci-timer.c better than I just did (as I know
I messed it up...)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It allows for cleaning up on a considerable amount of places. They did
port_get, hangup, kref_put. Now the only thing needed is to call
tty_port_tty_hangup which does exactly that. And they can also decide
whether to consider CLOCAL or completely ignore that.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It allows for cleaning up on a considerable amount of places. They did
port_get, wakeup, kref_put. Now the only thing needed is to call
tty_port_tty_wakeup which does exactly that.
One exception is ifx6x60 where tty_wakeup was open-coded. We now call
tty_wakeup properly there.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'v3.9-rc3' into next
Merge with mainline to bring in module_platform_driver_probe() and
devm_ioremap_resource().
Modern speed handling has been introduced in 2009 by commit
9b80fee149 (cdc_acm: Fix to use modern
speed interfaces) and the acm_tty_speed array has been unused since.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
Acked-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The buffer for responses must not overflow.
If this would happen, set a flag, drop the data and return
an error after user space has read all remaining data.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
CC: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The IMS PCU (Passenger Control Unit) device used custom protocol over serial
line, so it is presenting itself as CDC ACM device.
Now that we have proper in-kernel driver for it we need to black-list the
device in cdc-acm driver.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The option allows you to remove TTY and compile without errors. This
saves space on systems that won't support TTY interfaces anyway.
bloat-o-meter output is below.
The bulk of this patch consists of Kconfig changes adding "depends on
TTY" to various serial devices and similar drivers that require the TTY
layer. Ideally, these dependencies would occur on a common intermediate
symbol such as SERIO, but most drivers "select SERIO" rather than
"depends on SERIO", and "select" does not respect dependencies.
bloat-o-meter output comparing our previous minimal to new minimal by
removing TTY. The list is filtered to not show removed entries with awk
'$3 != "-"' as the list was very long.
add/remove: 0/226 grow/shrink: 2/14 up/down: 6/-35356 (-35350)
function old new delta
chr_dev_init 166 170 +4
allow_signal 80 82 +2
static.__warned 143 142 -1
disallow_signal 63 62 -1
__set_special_pids 95 94 -1
unregister_console 126 121 -5
start_kernel 546 541 -5
register_console 593 588 -5
copy_from_user 45 40 -5
sys_setsid 128 120 -8
sys_vhangup 32 19 -13
do_exit 1543 1526 -17
bitmap_zero 60 40 -20
arch_local_irq_save 137 117 -20
release_task 674 652 -22
static.spin_unlock_irqrestore 308 260 -48
Signed-off-by: Joe Millenbach <jmillenbach@gmail.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.
Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.
IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.
Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.
tty_insert_flip_string this time.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adding support "PSC Scanning, Magellan 800i" in cdc-acm
Very simple, but very necessary.
Suitable for all versions of the kernel > 2.6
Signed-off-by: Denis N Ladin <denladin@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some devices (ex Nokia C7) simply don't respond at all when data is sent
to some of their USB interfaces. The data gets stuck in the TTYs queue
and sits there until close(2), which them blocks because closing_wait
defaults to 30 seconds (even though the fd is O_NONBLOCK). This is
rarely desired. Implement the standard mechanism to adjust closing_wait
and let applications handle it how they want to.
See also 02303f7337 for usb_wwan.c.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.de>
Tested-by: Aleksander Morgado <aleksander@gnu.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
