kernel/linux.git/drivers/input/serio/libps2.c, branch v6.19.11

Input: include export.h in modules using EXPORT_SYMBOL*()

2025-08-21T19:00:59+00:00

A number of modules in the input subsystem use EXPORT_SYMBOL() and friends without explicitly including the corresponding header . 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

Input: libps2 - use guard notation when temporarily pausing serio ports

2024-10-04T07:58:14+00:00

Using guard notation makes the code more compact and error handling more robust by ensuring that serio ports are resumed in all code paths when control leaves critical section. Link: https://lore.kernel.org/r/20240905041732.2034348-3-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov

Input: libps2 - do not discard non-ack bytes when controlling LEDs

2023-05-18T18:40:32+00:00

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 Link: https://lore.kernel.org/r/20230511185252.386941-8-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov

Input: libps2 - introduce common interrupt handler

2023-05-18T18:40:32+00:00

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

Input: libps2 - fix aborting PS/2 commands

2023-05-18T18:40:32+00:00

When aborting PS/2 command the kernel should [re]set all flags before waking up waiters, otherwise waiting thread may read obsolete values of flags. Reported-by: Raul Rangel Reviewed-by: Raul E Rangel Link: https://lore.kernel.org/r/20230511185252.386941-6-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov

Input: libps2 - fix NAK handling

2023-05-18T18:40:32+00:00

Do not try to process "resend" or "reject" responses from the device as normal response data for a command. Reviewed-by: Raul E Rangel Link: https://lore.kernel.org/r/20230511185252.386941-5-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov

Input: libps2 - rework handling of command response

2023-05-18T18:40:32+00:00

It is not entirely correct that libps2 sets PS2_FLAG_CMD1 after the device acknowledges each byte sent to the device by the host. Rework the code so that PS2_FLAG_CMD1 and PS2_FLAG_CMD are set only once, at the beginning of PS/2 command execution. Reviewed-by: Raul E Rangel Link: https://lore.kernel.org/r/20230511185252.386941-4-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov

Input: libps2 - remove special handling of ACK for command byte

2023-05-18T18:40:32+00:00

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 Link: https://lore.kernel.org/r/20230511185252.386941-3-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov

Input: libps2 - attach ps2dev instances as serio port's drvdata

2023-05-18T18:40:32+00:00

In preparation of having unified interrupt handler for PS/2 devices, instead of attaching instances of psmouse and atkbd structures as serio's driver data, switch to attaching ps2dev instances. Reviewed-by: Raul Rangel Link: https://lore.kernel.org/r/20230511185252.386941-2-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov

input: libps2: mark data received in __ps2_command() as initialized

2022-10-03T21:03:21+00:00

KMSAN does not know that the device initializes certain bytes in ps2dev->cmdbuf. Call kmsan_unpoison_memory() to explicitly mark them as initialized. Link: https://lkml.kernel.org/r/20220915150417.722975-21-glider@google.com Signed-off-by: Alexander Potapenko Cc: Alexander Viro Cc: Alexei Starovoitov Cc: Andrey Konovalov Cc: Andrey Konovalov Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Christoph Hellwig Cc: Christoph Lameter Cc: David Rientjes Cc: Dmitry Vyukov Cc: Eric Biggers Cc: Eric Biggers Cc: Eric Dumazet Cc: Greg Kroah-Hartman Cc: Herbert Xu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: Jens Axboe Cc: Joonsoo Kim Cc: Kees Cook Cc: Marco Elver Cc: Mark Rutland Cc: Matthew Wilcox Cc: Michael S. Tsirkin Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Petr Mladek Cc: Stephen Rothwell Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vegard Nossum Cc: Vlastimil Babka Signed-off-by: Andrew Morton