usb: add usb_set_intfdata() documentation

USB drivers do not need to call usb_set_intfdata(intf, NULL) in their
usb_driver::disconnect callback because the core already does it in [1].

However, this fact is widely unknown, c.f.:

$ git grep "usb_set_intfdata(.*NULL)" | wc -l
215

Especially, setting the interface to NULL before all action completed
can result in a NULL pointer dereference. Not calling
usb_set_intfdata() at all in disconnect() is the safest method.

Add documentation to usb_set_intfdata() to clarify this point.

Also remove the call in usb-skeletion's disconnect() not to confuse
the new comers.

[1] function usb_unbind_interface() from drivers/usb/core/driver.c
Link: https://elixir.bootlin.com/linux/v6.0/source/drivers/usb/core/driver.c#L497

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20221128102954.3615579-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: usb-skeleton: Update min() to min_t()

This patch fixes the checkpatch.pl warning:
WARNING: min() should probably be min_t(size_t, count, MAX_TRANSFER)
+ size_t writesize = min(count, (size_t)MAX_TRANSFER);

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/20210922212037.GA8110@matrix-ESPRIMO-P710
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton: drop redundant in-urb check

The driver bails out at probe if we can't find a bulk-in endpoint or
if we fail to allocate the URB, so drop the check in read().

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191009170944.30057-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton: fix use-after-free after driver unbind

The driver failed to stop its read URB on disconnect, something which
could lead to a use-after-free in the completion handler after driver
unbind in case the character device has been closed.

Fixes: e7389cc9a7ff ("USB: skel_read really sucks royally")
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191009170944.30057-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton: fix NULL-deref on disconnect

The driver was using its struct usb_interface pointer as an inverted
disconnected flag and was setting it to NULL before making sure all
completion handlers had run. This could lead to NULL-pointer
dereferences in the dev_err() statements in the completion handlers
which relies on said pointer.

Fix this by using a dedicated disconnected flag.

Note that this is also addresses a NULL-pointer dereference at release()
and a struct usb_interface reference leak introduced by a recent runtime
PM fix, which depends on and should have been submitted together with
this patch.

Fixes: 4212cd74ca6f ("USB: usb-skeleton.c: remove err() usage")
Fixes: 5c290a5e42c3 ("USB: usb-skeleton: fix runtime PM after driver unbind")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191009170944.30057-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton: fix runtime PM after driver unbind

Since commit c2b71462d294 ("USB: core: Fix bug caused by duplicate
interface PM usage counter") USB drivers must always balance their
runtime PM gets and puts, including when the driver has already been
unbound from the interface.

Leaving the interface with a positive PM usage counter would prevent a
later bound driver from suspending the device.

Fixes: c2b71462d294 ("USB: core: Fix bug caused by duplicate interface PM usage counter")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191001084908.2003-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: usb-skeleton: make comment block in line with coding style

Comment block was not in accordance with coding style.
Fixes two checkpatch warnings:
WARNING: Block comments use * on subsequent lines
WARNING: Block comments use a trailing */ on a separate line

Signed-off-by: Jacob Huisman <jacobhuisman@kernelthusiast.com>
Link: https://lore.kernel.org/r/20190815174210.580-1-jacobhuisman@kernelthusiast.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: usb-skeleton: use irqsave() in USB's complete callback

The USB completion callback does not disable interrupts while acquiring
the lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: usb-skeleton: make MODULE_LICENSE and SPDX tag match

GPL v2 is the original license according to the old license text.
See f64cdd0e94f1faf3b7f2b03af71f70dc6d8da0c2.

Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton: Remove redundant license text

Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

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

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton: refactor endpoint retrieval

Use the new endpoint helpers to lookup the required bulk-in and bulk-out
endpoints.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: usb-skeleton: don't print on ENOMEM

All kmalloc-based functions print enough information on failures.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: usb-skeleton: don't print error when allocating urb fails

kmalloc will print enough information in case of failure.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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>

USB: usb-skeleton.c: add retry for nonblocking read

Updated skel_read() in usb-skeleton.c. When there is no data in the
buffer, we would allow retry for both blocking and nonblocking cases.
Original logic give retry only for blocking case. Actually we can also
allow retry for nonblocking case. This will reuse the existing retry
logic and handle the return of -EAGAIN in one place. Also if the data to
be read is short and can be retrieved in quick time, we can also give a
chance for nonblocking case and may catch the data and copy it back to
userspace in one read() call too.

Signed-off-by: Chen Wang <unicornxx.wang@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton.c: fix blocked forever in skel_read

In skel_read,the reader blocked in wait_for_completion before submit
bulk in urb.
Using processed_urb is for retaining the completion in the case that
previous interruptible wait in skel_read was interrupted and complete
before next skel_read. Replacing completion with waitqueue can avoid
working around the counting nature of completions
and fix the bug.

Signed-off-by: Du Xing duxing2007@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton.c: fix compilation error and restored kref_put on fail in skel_open

Fixing compilaton error.
Incrementing usage counter only on successful execution of skel_open.
Removing redundant locking

Some last changes in function skel_open and finally commit
52a7499 Revert "USB: usb-skeleton.c: fix open/disconnect race"
introduced a bug in function skel_open, which this patch fixes.

Changes since v2:
- refactoring
- Removing redundant mutex synchronization.

Changes since v1:
- Fixed accordingly feedback of Oliver Neukum oneukum@suse.de: also need to drop the lock.

Signed-off-by: Constantine Shulyupin <const@MakeLinux.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: usb-skeleton.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.

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

Revert "USB: usb-skeleton.c: fix open/disconnect race"

This reverts commit 26c71a79cade5ccad80e0752cd82f3518df48fb3.

It's not needed, to quote Ming Lei:
Looks you have queued the patch into your tree, but just now I
find the patch is not needed at all, since we have had
minor_rwsem(drivers/usb/core/file.c) for this purpose, please
drop the patch, sorry for it.

Cc: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb-skeleton.c: cleanup open_count

It is not necessary to use the 'open_count' for handling
runtime pm only, because runtinme pm has built-in counter
to handle this, so remove it to make code clean.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb-skeleton.c: fix open/disconnect race

If usb device is disconnected between usb_get_intfdata()
and kref_get() in skel_open(), kref_get may access a freed
object.

Also check if device is disconnected in ->open.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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>

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>

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>

USB: usb-skeleton: Remove unnecessary casts of private_data

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

USB: rename usb_buffer_alloc() and usb_buffer_free() users

For more clearance what the functions actually do,

usb_buffer_alloc() is renamed to usb_alloc_coherent()
usb_buffer_free() is renamed to usb_free_coherent()

They should only be used in code which really needs DMA coherency.

All call sites have been changed accordingly, except for staging
drivers.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Pedro Ribeiro <pedrib@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: BKL removal: usb-skeleton

BKL 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 Carvalho Chehab <mchehab@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB skeleton: 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>

USB: skeleton: Correct use of ! and &

Correct priority problem in the use of ! and &.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression E; constant C; @@
- !E & C
+ !(E & C)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: skeleton: fix coding style issues.

This fixes up the majority of the coding style issues in the
usb-skeleton driver.

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

USB: O_NONBLOCK in read path of skeleton

Non blocking IO is supported in the read path of usb-skeleton.
This is done by just not blocking. As support for handling signals
without stopping IO is already there, it can be used for O_NONBLOCK, too.

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

USB: make usb-skeleton honor O_NONBLOCK in write path

usb:usb-skeleton: honor O_NONBLOCK in write path

nonblocking writes are allowed by using down_trylock if necessary
to reserve an URB

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

USB: skel_read really sucks royally

The read code path of the skeleton driver really sucks

- skel_read works only for devices which always send data
- the timeout comes out of thin air
- it blocks signals for the duration of the timeout
- it disallows nonblocking IO by design

This patch fixes it by using a real urb, a completion and interruptible waits.

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

USB: skeleton: Use dev_info instead of info

338b67b0c1a97ca705023a8189cf41aa0828d294 removed the info macro and
replaced its uses with dev_info. This patch does so for
usb-skeleton.c, which was missed.

Signed-off-by: Matt Kraai <kraai@ftbfs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: remove unnecessary type casting of urb->context

urb->context code cleanup

Signed-off-by: Ming Lei <tom.leiming@gmail.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.de>

USB: usb-skeleton leaking locks on open

This weekend I was hacking around with a trivial USB driver for talking
to the boot load firmware of a USB Bit Whacker. It's running the
MicroChip Pic18 boot loader firmware and I'm putting together a flash
program for writing new FW to the thing.

Anyway in my use of the usb-skeleton.c as my starting point I discovered
my test program was getting hung up after attempting to write a buffer.
The application and driver where hung in a way that required me to
reboot to get it to clean up so I could try again.

It turned out the code path through skel_open can grap the driver's
io_mutex lock and forget to release it.

The following patch fixes the problem for me.

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

USB: usb-skeleton: use anchors in pre/post reset

use anchors in pre/post_reset

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

USB: usb-skeleton" use anchors in suspend/resume handling

use anchors in suspend/resume handling

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

USB: usb-skeleton: use anchors in disconnect handling

use anchors in disconnect handling

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

USB: usb-skeleton: usb anchor to implement flush

This patch set introduces usb_anchor and uses it to implement all modern
APIs in the skeleton driver.

- proper error reporting in the skeleton driver
- implementation of flush()

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

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>

USB: kill BKL in skeleton driver

Iet's kill BKL where we can. This is relative to the last patch to the
skeleton driver.

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

USB: fix skeleton driver

compilation of the skeleton driver is currently broken. It doesn't compile.
So while I am it:

- fix typo
- add comments to answer common questions
- actually allow autosuspend in the driver struct
- increase paralellism by restricting code under locks

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

USB: fix autosuspend race in skeleton driver

as the skeleton driver was made ready for autosuspend a race condition
was introduced. The reference to get device must be gotten before the
autosuspend counter is upped, as this operation may sleep, dropping BKL.
Dropping BKL means that the pointer to the device may become invalid.
Here's the fix.

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

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)

usbcore: non-hub-specific uses of autosuspend

This patch (as741) makes the non-hub parts of usbcore actually use the
autosuspend facilities added by an earlier patch.

Devices opened through usbfs are autoresumed and then
autosuspended upon close.

Likewise for usb-skeleton.

Devices are autoresumed for usb_set_configuration.


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

usb-skeleton: small update

o CodingStyle fixes
o Removes trailing spaces
o Do not make not needed initialiation of automatic variables
o Use usb_endpoint_* functions
o If we get an error in the write URB callback print an error message instead
of a debug one

(Pretty unrelated changes, but spliting this up doesn't pay off as our main
changes are just CodingStyle fixes).

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

USB: Make file operations structs in drivers/usb const.

Making structs const prevents accidental bugs and with the proper debug
options they're protected against corruption.

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

usb-skeleton: don't submit URBs after disconnection

This patch (as712b) is a slight revision of one submitted earlier. It
fixes the usb-skeleton example driver so that it won't try to submit
URBs after skel_disconnect() has returned. This could cause errors, if
the driver was unbound and then a different driver was bound to the
device. It also fixes a couple of small bugs in the skel_write()
routine.

The revised patch uses a slightly different test, suggested by Dave
Brownell, for determining whether to free a transfer buffer. It's a
little clearer than the earlier version.


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

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[PATCH] USB: remove some left over devfs droppings hanging around in the usb drivers

As there is no more usb devfs support, these bits would just confuse
people.

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

[PATCH] USB: fix usb-skeleton limit resource usage patch.

Prevents a compiler warning and uses down_interruptible() instead of down() in
process context.

Signed-off-by: Sam Bishop <sam@bishop.dhs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] USB: fix buffer size limiting in skeleton driver

Fix buffer size limiting.

Signed-off-by: Olav Kongas <ok@artecdesign.ee>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] USB: Limiting of resource use in skeleton driver

this introduces limits whose lack in the skeleton driver someone recently
complained about.

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

[PATCH] USB: remove .owner field from struct usb_driver

It is no longer needed, so let's remove it, saving a bit of memory.

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

[PATCH] devfs: Remove the mode field from usb_class_driver as it's no longer needed

Also fixes all drivers that set this field, and removes some other devfs
specfic USB logic.

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

drivers/usb/class/usblp.c | 3 +--
drivers/usb/core/file.c | 19 ++++---------------
drivers/usb/image/mdc800.c | 3 +--
drivers/usb/input/aiptek.c | 2 +-
drivers/usb/input/hiddev.c | 3 +--
drivers/usb/media/dabusb.c | 3 +--
drivers/usb/misc/auerswald.c | 3 +--
drivers/usb/misc/idmouse.c | 5 ++---
drivers/usb/misc/legousbtower.c | 5 ++---
drivers/usb/misc/rio500.c | 3 +--
drivers/usb/misc/sisusbvga/sisusb.c | 5 -----
drivers/usb/misc/usblcd.c | 9 ++++-----
drivers/usb/usb-skeleton.c | 3 +--
include/linux/usb.h | 7 ++-----
14 files changed, 22 insertions(+), 51 deletions(-)

[PATCH] USB: fix Bug in usb-skeleton.c

Compare endpoint address to USB_ENDPOINT_DIR_MASK to determine endpoint
direction...

From: "Conger, Chris A." <CHRIS.A.CONGER@saic.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!