Input: pegasus-notetaker - check pipe type when probing

Fix WARNING in pegasus_open/usb_submit_urb
Syzbot bug: https://syzkaller.appspot.com/bug?id=bbc107584dcf3262253ce93183e51f3612aaeb13

Warning raised because pegasus_driver submits transfer request for
bogus URB (pipe type does not match endpoint type). Add sanity check at
probe time for pipe value extracted from endpoint descriptor. Probe
will fail if sanity check fails.

Reported-and-tested-by: syzbot+04ee0cb4caccaed12d78@syzkaller.appspotmail.com
Signed-off-by: Soumya Negi <soumya.negi97@gmail.com>
Link: https://lore.kernel.org/r/20230404074145.11523-1-soumya.negi97@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: move from strlcpy with unused retval to strscpy

Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220818210022.6865-1-wsa+renesas@sang-engineering.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: remove third argument of usb_maxpacket()

The third argument of usb_maxpacket(): in_out has been deprecated
because it could be derived from the second argument (e.g. using
usb_pipeout(pipe)).

N.B. function usb_maxpacket() was made variadic to accommodate the
transition from the old prototype with three arguments to the new one
with only two arguments (so that no renaming is needed). The variadic
argument is to be removed once all users of usb_maxpacket() get
migrated.

CC: Ville Syrjala <syrjala@sci.fi>
CC: Dmitry Torokhov <dmitry.torokhov@gmail.com>
CC: Henk Vergonet <Henk.Vergonet@gmail.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20220317035514.6378-4-mailhol.vincent@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Input: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200707180857.GA30600@embeddedor
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: pegasus_notetaker - fix endpoint sanity check

The driver was checking the number of endpoints of the first alternate
setting instead of the current one, something which could be used by a
malicious device (or USB descriptor fuzzer) to trigger a NULL-pointer
dereference.

Fixes: 1afca2b66aac ("Input: add Pegasus Notetaker tablet driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Martin Kepplinger <martink@posteo.de>
Acked-by: Vladis Dronov <vdronov@redhat.com>
Link: https://lore.kernel.org/r/20191210113737.4016-2-johan@kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

treewide: Add SPDX license identifier for more missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Input: pegasus_notetaker - do not rely on input_dev->users

If the device is unused and suspended, a call to open will cause the
device to autoresume through the call to usb_autopm_get_interface().

input_dev->users is already incremented by the input subsystem,
therefore this expression will always be evaluated to true:

if (pegasus->dev->users && usb_submit_urb(pegasus->irq, GFP_NOIO) < 0)
retval = -EIO;

The same URB will then be fail when resubmitted in pegasus_open().

Introduce pegasus->is_open to keep track of the state instead.

Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: pagasus_notetaker - fix deadlock in autosuspend

usb_autopm_get_interface() that is called in pegasus_open() does an
autoresume if the device is suspended.

input_dev->mutex used in pegasus_resume() is in this case already
taken by the input subsystem and will cause a deadlock.

Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: pegasus_notetaker - directly include workqueue header

According to the kernel's guidelines, let's directly include the
workqueue functions we use.

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: pegasus_notetaker - set device mode in reset_resume() if in use

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: pegasus_notetaker - cancel workqueue's work in suspend()

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: pegasus_notetaker - fix usb_autopm calls to be balanced

We should only "put" the interface if submitting URB or setting tablet mode
in pegasus_open() fails, otherwise leave it to pegasus_close().

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: pegasus_notetaker - handle usb control msg errors

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: add Pegasus Notetaker tablet driver

This adds a driver for the Pegasus Notetaker Pen. When connected,
this uses the Pen as an input tablet.

This device was sold in various different brandings, for example
"Pegasus Mobile Notetaker M210",
"Genie e-note The Notetaker",
"Staedtler Digital ballpoint pen 990 01",
"IRISnotes Express" or
"NEWLink Digital Note Taker".

Here's an example, so that you know what we are talking about:
http://www.genie-online.de/genie-e-note-2/

https://pegatech.blogspot.com/ seems to be a remaining official resource.

This device can also transfer saved (offline recorded handwritten) data and
there are userspace programs that do this, see https://launchpad.net/m210
(Well, alternatively there are really fast scanners out there :)

It's *really* fun to use as an input tablet though! So let's support this
for everybody.

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>