usb, HID: Remove Vernier devices from lsusb and hid_ignore_list

Removes Vernier Software & Technology devices from the ldusb
driver and the hid_ignore_list table of the usbhid driver in the
Linux tr

usb, HID: Remove Vernier devices from lsusb and hid_ignore_list

Removes Vernier Software & Technology devices from the ldusb
driver and the hid_ignore_list table of the usbhid driver in the
Linux tree. These devices will now be supported via the hidraw
driver.

A user space driver for these devices will be found in the
Go! Software Development Kit from Vernier at
http://www.vernier.com/downloads/software-development-kits/go-sdk/.
These devices are also be supported by the LabQuest2 standalone
interface shown at http://www.vernier.com/products/interfaces/labq2/
and the LoggerPro for Linux software shown at
http://www.vernier.com/downloads/logger-pro-linux/.

Signed-off-by: Dennis O'Brien <dennis.obrien@eqware.net>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

show more ...

usb: delete non-required instances of include <linux/init.h>

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 o

usb: delete non-required instances of include <linux/init.h>

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>

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USB: ldusb: remove custom dbg_info() macro

We want to get rid of CONFIG_USB_DEBUG, so remove the reliance of the
ldusb driver on it. Don't use the custom macro, or a special module
parameter, inste

USB: ldusb: remove custom dbg_info() macro

We want to get rid of CONFIG_USB_DEBUG, so remove the reliance of the
ldusb driver on it. Don't use the custom macro, or a special module
parameter, instead, rely on the in-kernel dynamic debugging
infrastructure, which is much easier to use, and consistant across the
whole kernel.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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USB: ldusb.c: remove err() usage

err() was a very old USB-specific macro that I thought had
gone away. This patch removes it from being used in the
driver and uses dev_err() instead.

CC: Michael H

USB: ldusb.c: remove err() usage

err() was a very old USB-specific macro that I thought had
gone away. This patch removes it from being used in the
driver and uses dev_err() instead.

CC: Michael Hund <mhund@ld-didactic.de>
CC: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
CC: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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USB: convert drivers/usb/* to use module_usb_driver()

This converts the drivers in drivers/usb/* to use the
module_usb_driver() macro which makes the code smaller and a bit
simpler.

Added bonus is

USB: convert drivers/usb/* to use module_usb_driver()

This converts the drivers in drivers/usb/* to use the
module_usb_driver() macro which makes the code smaller and a bit
simpler.

Added bonus is that it removes some unneeded kernel log messages about
drivers loading and/or unloading.

Cc: Simon Arlott <cxacru@fire.lp0.eu>
Cc: Duncan Sands <duncan.sands@free.fr>
Cc: Matthieu CASTET <castet.matthieu@free.fr>
Cc: Stanislaw Gruszka <stf_xl@wp.pl>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Juergen Stuber <starblue@users.sourceforge.net>
Cc: Cesar Miquel <miquel@df.uba.ar>
Cc: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Michael Hund <mhund@ld-didactic.de>
Cc: Zack Parsons <k3bacon@gmail.com>
Cc: Melchior FRANZ <mfranz@aon.at>
Cc: Tomoki Sekiyama <tomoki.sekiyama@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: use usb_endpoint_maxp() instead of le16_to_cpu()

Now ${LINUX}/drivers/usb/* can use usb_endpoint_maxp(desc) to get maximum packet size
instead of le16_to_cpu(desc->wMaxPacketSize).
This patch f

USB: use usb_endpoint_maxp() instead of le16_to_cpu()

Now ${LINUX}/drivers/usb/* can use usb_endpoint_maxp(desc) to get maximum packet size
instead of le16_to_cpu(desc->wMaxPacketSize).
This patch fix it up

Cc: Armin Fuerst <fuerst@in.tum.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Johannes Erdfelt <johannes@erdfelt.com>
Cc: Vojtech Pavlik <vojtech@suse.cz>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: David Kubicek <dave@awk.cz>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Brad Hards <bhards@bigpond.net.au>
Acked-by: Felipe Balbi <balbi@ti.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Dahlmann <dahlmann.thomas@arcor.de>
Cc: David Brownell <david-b@pacbell.net>
Cc: David Lopo <dlopo@chipidea.mips.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Michal Nazarewicz <m.nazarewicz@samsung.com>
Cc: Xie Xiaobo <X.Xie@freescale.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Jiang Bo <tanya.jiang@freescale.com>
Cc: Yuan-hsin Chen <yhchen@faraday-tech.com>
Cc: Darius Augulis <augulis.darius@gmail.com>
Cc: Xiaochen Shen <xiaochen.shen@intel.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: OKI SEMICONDUCTOR, <toshiharu-linux@dsn.okisemi.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Ben Dooks <ben@simtec.co.uk>
Cc: Thomas Abraham <thomas.ab@samsung.com>
Cc: Herbert Pötzl <herbert@13thfloor.at>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Cc: Roman Weissgaerber <weissg@vienna.at>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Tony Olech <tony.olech@elandigitalsystems.com>
Cc: Florian Floe Echtler <echtler@fs.tum.de>
Cc: Christian Lucht <lucht@codemercs.com>
Cc: Juergen Stuber <starblue@sourceforge.net>
Cc: Georges Toth <g.toth@e-biz.lu>
Cc: Bill Ryder <bryder@sgi.com>
Cc: Kuba Ober <kuba@mareimbrium.org>
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: ldusb: add several new devices

Added several new devices to ldusb and excluded them from the HID driver.

Signed-off-by: Michael Hund <mhund@ld-didactic.de>
Signed-off-by: Greg Kroah-Hartman <g

USB: ldusb: add several new devices

Added several new devices to ldusb and excluded them from the HID driver.

Signed-off-by: Michael Hund <mhund@ld-didactic.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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tree-wide: fix comment/printk typos

"gadget", "through", "command", "maintain", "maintain", "controller", "address",
"between", "initiali[zs]e", "instead", "function", "select", "already",
"equal",

tree-wide: fix comment/printk typos

"gadget", "through", "command", "maintain", "maintain", "controller", "address",
"between", "initiali[zs]e", "instead", "function", "select", "already",
"equal", "access", "management", "hierarchy", "registration", "interest",
"relative", "memory", "offset", "already",

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

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llseek: automatically add .llseek fop

All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three

llseek: automatically add .llseek fop

All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>

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USB: Convert concatenated __FILE__ to %s, __FILE__

Reduces string space a bit
Neaten a macro redefine of dbg

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@s

USB: Convert concatenated __FILE__ to %s, __FILE__

Reduces string space a bit
Neaten a macro redefine of dbg

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: BKL removal: ldusb

BKL was not needed at all. Removed without replacement.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: Push BKL on open down into the drivers

Straightforward push into the drivers to allow
auditing individual drivers separately

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Mauro Ca

USB: Push BKL on open down into the drivers

Straightforward push into the drivers to allow
auditing individual drivers separately

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB misc: make USB device id constant

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 th

USB misc: make USB device id constant

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>

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USB: ldusb should signal an error in poll if the device is disconnected

poll() should test for a disconnection of the device.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kr

USB: ldusb should signal an error in poll if the device is disconnected

poll() should test for a disconnection of the device.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: remove vernier labpro from ldusb

Labpro device is in both ldusb and vstusb device tables.
Should only be a vstusb device.

Signed-off-by: stephen ware <stephen.ware@eqware.net>
Signed-off-by: G

USB: remove vernier labpro from ldusb

Labpro device is in both ldusb and vstusb device tables.
Should only be a vstusb device.

Signed-off-by: stephen ware <stephen.ware@eqware.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: remove PICDEM FS USB demo (04d8:000c) device from ldusb

Microchip has changed the PICDEM FS USB demo device (0x04d8:000c)
to use bulk transfer and not interrupt transfer. So I've updated the li

USB: remove PICDEM FS USB demo (04d8:000c) device from ldusb

Microchip has changed the PICDEM FS USB demo device (0x04d8:000c)
to use bulk transfer and not interrupt transfer. So I've updated the libusb
based program here (Post #31).
http://forum.microchip.com/tm.aspx?m=106426&mpage=2

So I believe that the in-kernel ldusb driver will no longer work with the
demo firmware. It should be removed.


Signed-off-by: Xiaofan Chen <xiaofanc@gmail.com>
Cc: Michael Hund <MHund@LD-Didactic.de>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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usb: ldusb: ld_usb semaphore to mutex

Signed-off-by: Daniel Walker <dwalker@mvista.com>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.

USB: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: add new vernier product id to ldusb.c

I have a new ldusb device to go into the device table. Jiri has merged
the change for hiddev quirks already.


From: Stephen Ware <stephen.ware@eqware.net>

USB: add new vernier product id to ldusb.c

I have a new ldusb device to go into the device table. Jiri has merged
the change for hiddev quirks already.


From: Stephen Ware <stephen.ware@eqware.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: misc: ldusb: clean up urb->status usage

This done in anticipation of removal of urb->status, which will make
that patch easier to review and apply in the future.

Signed-off-by: Greg Kroah-Hart

USB: misc: ldusb: clean up urb->status usage

This done in anticipation of removal of urb->status, which will make
that patch easier to review and apply in the future.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: prevent char device open/deregister race

This patch (as908) adds central protection in usbcore for the
prototypical race between opening and unregistering a char device.
The spinlock used to pr

USB: prevent char device open/deregister race

This patch (as908) adds central protection in usbcore for the
prototypical race between opening and unregistering a char device.
The spinlock used to protect the minor-numbers array is replaced with
an rwsem, which can remain locked across a call to a driver's open()
method. This guarantees that open() and deregister() will be mutually
exclusive.

The private locks currently used in several individual drivers for
this purpose are no longer necessary, and the patch removes them. The
following USB drivers are affected: usblcd, idmouse, auerswald,
legousbtower, sisusbvga/sisusb, ldusb, adutux, iowarrior, and
usb-skeleton.

As a side effect of this change, usb_deregister_dev() must not be
called while holding a lock that is acquired by open(). Unfortunately
a number of drivers do this, but luckily the solution is simple: call
usb_deregister_dev() before acquiring the lock.

In addition to these changes (and their consequent code
simplifications), the patch fixes a use-after-free bug in adutux and a
race between open() and release() in iowarrior.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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USB: ldusb bugfix

This patch fixes a problem reported with consecutive reads in the ldusb
driver.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: add picdem device to ldusb

Hi Greg:

I have found that /drivers/usb/misc/ldusb.c works with the "PICDEM Full
Speed USB"
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=

USB: add picdem device to ldusb

Hi Greg:

I have found that /drivers/usb/misc/ldusb.c works with the "PICDEM Full
Speed USB"
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en021940


Signed-off-by: Joey S Goncalves <jgoncalves@peragrin.com>
Cc: Michael Hund <MHund@LD-Didactic.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1

IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

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)

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USB: ldusb: Use usb_endpoint_* functions.

Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>