A number of modules in the input subsystem use EXPORT_SYMBOL() and
friends without explicitly including the corresponding header
<linux/export.h>. While the build currently succeeds due to this header
being pulled in transitively, this is not guaranteed to be the case in
the future.
Let's add the explicit include to make the dependencies clear and
prevent future build breakage.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Upon receiving a PS/2 command the device and controller are supposed to
stop sending normal data (scancodes or movement packets) and instead
immediately start delivering ACK/NAK and command response. Unfortunately
often EC has an output buffer which may contain latched data by the time
the EC receives a command from the host. The kernel used to ignore such
data, but that may cause "stuck" keys if the data dropped happens to be a
break code or a part of a break code. This occasionally happens, for
example, on Chromebooks when the kernel tries to toggle CapsLock LED on
a keyboard while user releases Alt+Search keyboard shortcut.
Fix this by passing the first non-ACK byte to the normal handler for a
handful of PS/2 commands that are expected to be used during normal device
operation (as opposed to probe/configuration time).
Reviewed-by: Raul E Rangel <rrangel@chromium.org>
Link: https://lore.kernel.org/r/20230511185252.386941-8-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Instead of exposing inner workings of libps2 to drivers such as atkbd and
psmouse, have them define pre-receive and receive callbacks, and provide a
common handler that can be used with underlying serio port.
While at this add kerneldoc to the module.
Link: https://lore.kernel.org/r/ZGK81cxqjr/KS1kA@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
When getting unexpected data while waiting for an acknowledgement it does
not matter what command phase is currently executed, and ps2_handle_ack()
should indicate that no further processing is needed for the received data
byte. Remove PS2_FLAG_ACK_CMD and associated handling.
Note that while it is possible to make ps2_handle_ack (and
ps2_handle_repsonse) return void, it will be done when the code will be
converted to common PS/2 interrupt handler later.
Reviewed-by: Raul E Rangel <rrangel@chromium.org>
Link: https://lore.kernel.org/r/20230511185252.386941-3-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.
This patch fixes the following warning:
drivers/input/serio/libps2.c: In function ‘ps2_handle_ack’:
drivers/input/serio/libps2.c:407:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (ps2dev->flags & PS2_FLAG_NAK) {
^
drivers/input/serio/libps2.c:417:2: note: here
case 0x00:
^~~~
Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
When we probe PS/2 devices we first issue "Get ID" command and only if we
receive what we consider a valid keyboard or mouse ID we disable the device
and continue with protocol detection. That means that the device may be
transmitting motion or keystroke data, while we expect ACK response.
Instead of signaling failure if we see anything but ACK/NAK let's ignore
"garbage" response until we see ACK for the command byte (first byte). The
checks for subsequent ACKs of command parameters will continue be strict.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The devices are allowed to respond to either command byte or command
parameter with a NAK (0xfe), and the host is supposed to resend the
"correct" byte. The device then will either respond with ACK or ERR (0xfc).
Let's teach libps2 to handle the NAK responses properly, so that individual
drivers do not need to handle them.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Debugging via i8042.debug and analyzing raw PS/2 data stream may be
cumbersome as you need to locate the boundaries of commands, decipher the
sliced commands, etc, etc. Let's add a bit more high level debug statements
for ps2_sendbyte(), ps2_command(), and ps2_sliced_command().
We do not introduce a new module parameter, but rater rely on the kernel
having dynamic debug facility enabled (which most everyone has nowadays).
Enable with:
echo "file libps2.c +pf" > /sys/kernel/debug/dynamic_debug/control
or add "libps2.dyndbg=+pf" to the kernel command line.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
In preparation to adding some debugging statements to PS/2 control
sequences let's move psmouse_sliced_command() into libps2 and rename it
to ps2_sliced_command().
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Instead of using unsigned char for the byte data switch to using u8. Also
use unsigned int for the command codes and timeouts, and have
ps2_handle_ack() and ps2_handle_response() return bool instead of int, as
they do not return error codes but rather signal whether a byte was handled
or not handled. ps2_is_keyboard_id() now returns bool as well.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Individual labels of switch statements should have the same indentation
level as the switch statement itself.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
As explained in 1407814240-4275-1-git-send-email-decui@microsoft.com we
have a hard load dependency between i8042 and atkbd which prevents
keyboard from working on Gen2 Hyper-V VMs.
> hyperv_keyboard invokes serio_interrupt(), which needs a valid serio
> driver like atkbd.c. atkbd.c depends on libps2.c because it invokes
> ps2_command(). libps2.c depends on i8042.c because it invokes
> i8042_check_port_owner(). As a result, hyperv_keyboard actually
> depends on i8042.c.
>
> For a Generation 2 Hyper-V VM (meaning no i8042 device emulated), if a
> Linux VM (like Arch Linux) happens to configure CONFIG_SERIO_I8042=m
> rather than =y, atkbd.ko can't load because i8042.ko can't load(due to
> no i8042 device emulated) and finally hyperv_keyboard can't work and
> the user can't input: https://bugs.archlinux.org/task/39820
> (Ubuntu/RHEL/SUSE aren't affected since they use CONFIG_SERIO_I8042=y)
To break the dependency we move away from using i8042_check_port_owner()
and instead allow serio port owner specify a mutex that clients should use
to serialize PS/2 command stream.
Reported-by: Mark Laws <mdl@60hz.org>
Tested-by: Mark Laws <mdl@60hz.org>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The data race happens on ps2dev->cmdcnt and ps2dev->cmdbuf contents.
__ps2_command reads that data concurrently with the interrupt handler. As
the result, for example, if a response arrives just after the timeout,
__ps2_command can copy out garbage from ps2dev->cmdbuf but then see that
ps2dev->cmdcnt is 0 and return success.
Stop the interrupt handler with serio_pause_rx() before reading the
results.
The data race was found with KernelThreadSanitizer (KTSAN).
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Max BrenerandDmitry Torokhov
Alexander PotapenkoandAndrew Morton
Gustavo A. R. SilvaandDmitry Torokhov
Thomas GleixnerandGreg Kroah-Hartman
Gustavo A. R. SilvaandDmitry Torokhov
Dmitry VyukovandDmitry Torokhov
Paul GortmakerandDmitry Torokhov
Justin P. MattockandJiri Kosina