This is now set by the usb-serial core, no need for the driver to
individually set it.
Thanks to Alan Stern for the idea to get rid of it.
Cc: William Greathouse <wgreathouse@smva.com>
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Gary Brubaker <xavyer@ix.netcom.com>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Matthias Urlichs <smurf@smurf.noris.de>
Cc: Support Department <support@connecttech.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Bart Hartgers <bart.hartgers@gmail.com>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Preston Fick <preston.fick@silabs.com>
Cc: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Andrew Worsley <amworsley@gmail.com>
Cc: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Aleksey Babahin <tamerlan311@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Donald Lee <donald@asix.com.tw>
Cc: Julia Lawall <julia@diku.dk>
Cc: Michal Sroczynski <msroczyn@gmail.com>
Cc: Wang YanQing <Udknight@gmail.com>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Cc: Rigbert Hamisch <rigbert@gmx.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Adhir Ramjiawan <adhirramjiawan0@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is now set by the usb-serial core, no need for the driver to
individually set it.
Thanks to Alan Stern for the idea to get rid of it.
Cc: William Greathouse <wgreathouse@smva.com>
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Gary Brubaker <xavyer@ix.netcom.com>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Matthias Urlichs <smurf@smurf.noris.de>
Cc: Support Department <support@connecttech.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Bart Hartgers <bart.hartgers@gmail.com>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Preston Fick <preston.fick@silabs.com>
Cc: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Andrew Worsley <amworsley@gmail.com>
Cc: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Aleksey Babahin <tamerlan311@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Donald Lee <donald@asix.com.tw>
Cc: Julia Lawall <julia@diku.dk>
Cc: Michal Sroczynski <msroczyn@gmail.com>
Cc: Wang YanQing <Udknight@gmail.com>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Thomas Tuttle <ttuttle@chromium.org>
Cc: Rigbert Hamisch <rigbert@gmx.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Adhir Ramjiawan <adhirramjiawan0@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dbg() was used a lot a long time ago to trace code flow. Now that we have
ftrace, this isn't needed at all, so remove these calls.
CC: Johan Hovold <jhovold@gmail.com>
CC: Donald Lee <donald@asix.com.tw>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch added the support of MCS7810 device for the mos7840 driver.
The MCS7810 device supports single USB2.0-to-Serial port with
a LED indicator for reflecting transmission or reception activity.
Signed-off-by: Donald Lee <donald@asix.com.tw>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A MCS7820 device supports two serial ports and a MCS7840 device supports
four serial ports. Both devices use the same driver, but the attach function
in driver was unable to correctly handle the port numbers for MCS7820
device. This problem has been fixed in this patch and this fix has been
verified on x86 Linux kernel 3.2.9 with both MCS7820 and MCS7840 devices.
Signed-off-by: Donald Lee <donald@asix.com.tw>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This converts the mos7840.c driver to use the module_usb_serial_driver() call
instead of having to have a module_init/module_exit function, saving a lot
of duplicated code.
CC: Johan Hovold <jhovold@gmail.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1526) modifies the following usb-serial drivers to
utilize the new usb_serial_{de}register_drivers() routines:
keyspan, kl5kusb105, kobil_sct, mct_u232, mos7720,
mos7840, and moto_modem.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use dev_err_console in write paths for devices which can be used as a
console but do not use the generic write implementation.
Compile-only tested.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
module_param(bool) used to counter-intuitively take an int. In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.
It's time to remove the int/unsigned int option. For this version
it'll simply give a warning, but it'll break next kernel version.
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Remove unnecessary reinitialisations of urb->dev before each submission,
which were based on the (no longer valid) assumption that serial->dev
will be set to NULL on close.
Compile-only tested.
Cc: Matthias Bruestle and Harald Welte <support@reiner-sct.com>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Peter Berger <pberger@brimson.com>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Support Department <support@connecttech.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This small untidiness with two returns in a row was copy and pasted
into mos7720.c and mos7840.c.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
We don't use it so we can trim it from here as we try and stamp the file
object dependencies out of the serial code.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Doing tiocmget was such fun we should do tiocmset as well for the same
reasons
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We don't actually need this and it causes problems for internal use of
this functionality. Currently there is a single use of the FILE * pointer.
That is the serial core which uses it to check tty_hung_up_p. However if
that is true then IO_ERROR is also already set so the check may be removed.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Simple pasting job using the new ops function. Also fix a couple of devices
directly returning the internal struct (which happens at this point to match
for the fields that matter but isn't correct or futureproof)
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The TIOCGICOUNT device ioctl in both mos7720.c and mos7840.c allows
unprivileged users to read uninitialized stack memory, because the
"reserved" member of the serial_icounter_struct struct declared on the
stack is not altered or zeroed before being copied back to the user.
This patch takes care of it.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add the USB IDs needed to support the B&B USOPTL4-4P, USO9ML2-2P, and
USO9ML2-4P. This patch expands and corrects a typo in the patch sent
on 08-31-2010.
Signed-off-by: Dave Ludlow <dave.ludlow@bay.ws>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add the USB ID needed to support B&B Electronic's 2-port, optically-isolated,
powered, USB to RS485 converter.
Signed-off-by: Dave Ludlow <dave.ludlow@bay.ws>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Greg prefers this to go through the trivial tree.
http://lkml.org/lkml/2010/6/24/1
There are about 2500 void functions in drivers/usb
Only a few used return; at end of function.
Standardize them a bit.
Moved a statement down a line in drivers/usb/host/u132-hcd.c
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
BKL isn't anymore present into this file thus it is no necessary still include smp_lock.h.
Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We have lots of callers that do not need to do this in the first place.
Remove the calls as they both cost CPU and for big buffers can mess up the
multi-page allocation avoidance.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The id_table field of the struct usb_device_id is constant in <linux/usb.h>
so it is worth to make the initialization data also constant.
The semantic match that finds this kind of pattern is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
disable decl_init,const_decl_init;
identifier I1, I2, x;
@@
struct I1 {
...
const struct I2 *x;
...
};
@s@
identifier r.I1, y;
identifier r.x, E;
@@
struct I1 y = {
.x = E,
};
@c@
identifier r.I2;
identifier s.E;
@@
const struct I2 E[] = ... ;
@depends on !c@
identifier r.I2;
identifier s.E;
@@
+ const
struct I2 E[] = ...;
// </smpl>
Signed-off-by: Németh Márton <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Cc: cocci@diku.dk
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
The modem ioctls are not routed via the ioctl method so kill the old dead
code. The correct code is also already present and hooked in.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I've opened up the case, and the chips in the ATEN UC2324 are:
Moschip
MCS7840CV-AA
69507-6B1
0650
(USB to 4-port serial)
(logo with AF kerned together) 0748
24BC02
SINGLP
(unknown 8-pin chip)
(logo looks like 3 or Z in circle)
ZT3243LEEA 0752
B7A16420.T
(4 chips, so this will be RS232 line driver)
(Probably equivalent of Sipex SP3243)
So the ATEN 2324 (aten2011.c driver), is definitely the Moschip 7840,
and should use the mos7840.c driver. I expect you will remove the
aten2011.c driver from the staging area.
From the aten2011.c source code, the device ID for the UC2322 (2 port
serial) is 0x7820, just like the Moschip evaluation board. This value
should be added to the device id table of mos7840.c.
Here's a patch that adds these devices to the driver.
From: Russell Lang <gsview@ghostgum.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 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>
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>
This patch removes all the unnecessary "\n"s that the debug print
statements have, which result in everything appearing double spaced
and unreadable in the logs.
Signed-off-by: Tony Cook <tony-cook@bigpond.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
This removes tty->low_latency from all USB serial drivers that push
data into the tty layer at hard interrupt context. It's no longer needed
and actually harmful.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes a problem with any mos7840 device where the use of the field "minor" before it is
initialised results in all the devices being overlaid in memory (minor = 0 for all instances)
Contributed by: Phillip Branch
Signed-off-by: Tony Cook <tony-cook@bigpond.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
add USB ids for the mos7840 based ATEN International serial devices.
Contributed by: Phillip Branch
Signed-off-by: Tony Cook <tony-cook@bigpond.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some of the usb-serial drivers are starting to use urb->status in ways
they should not be doing. This fixes up some of them to prevent that.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
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>
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 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>
The test for an mos7840_set_uart_reg() error return value only works when
status is signed. propagate its error value.
Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Cc: SL Baur <steve@xemacs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The usb-serial core no longer checks these fields so remove them from
all of the individual drivers. They will be removed from the usb-serial
core in a patch later in the series.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add support for the mos7820/7840-based B&B USOPTL4_2/USOPTL4_4 USB/RS485
converter to mos7840.c
Signed-off-by: Dave Ludlow <dave.ludlow@bay.ws>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Coverity (1709, 1710, 1711, 1712, 1713) actually flagged these as
REVERSE_INULLs (NULL check performed after dereference). But looking at
the other drivers I can't see any similar tests and the USB core already
makes sure urb is non-null - so might as well get rid of the checks.
Signed-off-by: Florin Malita <fmalita@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The MOS driver is "interesting", in a bad kind of 'how the hell did this
get merged' kind of way
- Remove the bogus termios change check
- Remove the duplicate code for half the ioctls
- Remove the supporting code to duplicate the ioctl code
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>
This done in anticipation of removal of urb->status, which will make
that patch easier to review and apply in the future.
Cc: <linux-usb-devel@lists.sourceforge.net>
Cc: Paul Schroeder <pschroeder@uplogix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes:
- breaking DMA rules about buffers
- usage of _global_ variables to save a single device's attributes
- racy access to urb->status
- smp monotonity issue with statistics
- use of one buffer for many simultaneous URBs
- error handling introduced
- several instances of following NULL pointers
- use after free
- unnecessary GFP_ATOMIC
- GFP_KERNEL in interrupt
- various cleanups
- write room granularity issue that bit cdc-acm
- race in shutdown
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Every usb serial driver should have a pointer to the corresponding usb driver.
So the usb serial core can add a new id not only to the usb serial driver, but
also to the usb driver.
Also the usb drivers of ark3116, mos7720 and mos7840 missed the flag
no_dynamic_id=1. This is added now.
Signed-off-by: Johannes Hölzl <johannes.hoelzl@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Several drivers have bogus ioctl code that tries unneccessarily to
override the standard processing. In the three cases here the actual code
is not only wrong but also not required as they implement the proper
set_termios method as well.
Remove the junk.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is the grungy swap all the occurrences in the right places patch that
goes with the updates. At this point we have the same functionality as
before (except that sgttyb() returns speeds not zero) and are ready to
begin turning new stuff on providing nobody reports lots of bugs
If you are a tty driver author converting an out of tree driver the only
impact should be termios->ktermios name changes for the speed/property
setting functions from your upper layers.
If you are implementing your own TCGETS function before then your driver
was broken already and its about to get a whole lot more painful for you so
please fix it 8)
Also fill in c_ispeed/ospeed on init for most devices, although the current
code will do this for you anyway but I'd like eventually to lose that extra
paranoia
[akpm@osdl.org: bluetooth fix]
[mp3@de.ibm.com: sclp fix]
[mp3@de.ibm.com: warning fix for tty3270]
[hugh@veritas.com: fix tty_ioctl powerpc build]
[jdike@addtoit.com: uml: fix ->set_termios declaration]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
SLAB_ATOMIC is an alias of GFP_ATOMIC
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes an obvious check-after-dereference spotted by the
Coverity checker.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)