kernel/linux.git/drivers/input/serio/libps2.c, branch v4.19.77

Input: libps2 - relax command byte ACK handling

2018-02-03T00:50:28+00:00

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

Input: libps2 - support retransmission of command data

2018-02-03T00:50:27+00:00

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

Input: libps2 - add debugging statements

2018-02-03T00:50:25+00:00

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

Input: psmouse - move sliced command implementation to libps2

2018-02-03T00:50:24+00:00

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

Input: libps2 - use u8 for byte data

2018-02-03T00:50:21+00:00

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

Input: libps2 - fix switch statement formatting

2018-02-03T00:50:18+00:00

Individual labels of switch statements should have the same indentation level as the switch statement itself. Signed-off-by: Dmitry Torokhov

Input: i8042 - break load dependency between atkbd/psmouse and i8042

2016-07-27T21:20:09+00:00

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 Tested-by: Mark Laws Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov

Input: psmouse - fix data race in __ps2_command

2015-09-29T23:08:29+00:00

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 Signed-off-by: Dmitry Torokhov

Input: delete non-required instances of include

2014-01-07T07:23:57+00:00

None of these files are actually using any __init type directives and hence don't need to include . 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 Signed-off-by: Dmitry Torokhov

Input: libps2.c: fix comment typo arrrives.

2011-06-27T10:28:56+00:00

Fix a typo in a comment. Signed-off-by: Justin P. Mattock Signed-off-by: Jiri Kosina