From 1523d8bb2e066bec297f7a03ce4a0d8cada8f383 Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Mon, 5 Mar 2018 13:17:43 +1000 Subject: Extract and reset the abs fuzz value for the x/y axes The kernel fuzz handling is buggy, especially when we want to rely on the fuzz value for our hysteresis. But since this is a hw property and (at least sometimes) set by the driver, we can't make this a pure libinput hwdb set either. So our workaround is: * extract the (non-zero) fuzz into a udev property so we don't lose it * set the fuzz to 0 to disable the in-kernel hysteresis * overwrite our internal absinfo with the property fuzz This way we get to use the hw-specified fuzz without having the kernel muck around with it. We also get to use the EVDEV_ABS_ values in 60-evdev.hwdb to override a driver-set fuzz. Two drawbacks: - we're resetting the kernel fuzz to 0, this affects any other users of the device node. That's probably a minor impact only. - we can only save this in a udev property there's a risk of this information getting lost when playing around with udev rules. That too should be a minor issue. https://bugs.freedesktop.org/show_bug.cgi?id=105303 Signed-off-by: Peter Hutterer --- udev/90-libinput-model-quirks.rules.in | 1 - udev/libinput-model-quirks.c | 58 ++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+), 1 deletion(-) (limited to 'udev') diff --git a/udev/90-libinput-model-quirks.rules.in b/udev/90-libinput-model-quirks.rules.in index e7d56bbe..5ddc0ba4 100644 --- a/udev/90-libinput-model-quirks.rules.in +++ b/udev/90-libinput-model-quirks.rules.in @@ -15,7 +15,6 @@ KERNEL!="event*", GOTO="libinput_model_quirks_end" # First, run the program and import the LIBINPUT_MODEL_FIRMWARE_VERSION # environment (if any) KERNELS=="*input*", \ - ENV{ID_INPUT_TOUCHPAD}=="1", \ IMPORT{program}="@UDEV_TEST_PATH@libinput-model-quirks %S%p" # Second, match on anything with that env set and import from the hwdb diff --git a/udev/libinput-model-quirks.c b/udev/libinput-model-quirks.c index 2dc917d5..d1d5a68a 100644 --- a/udev/libinput-model-quirks.c +++ b/udev/libinput-model-quirks.c @@ -31,6 +31,7 @@ #include #include #include +#include #include "libinput-util.h" @@ -107,6 +108,61 @@ handle_touchpad(struct udev_device *device) handle_touchpad_synaptics(device); } +/** + * For a non-zero fuzz on the x/y axes, print that fuzz as property and + * reset the kernel's fuzz to 0. + * https://bugs.freedesktop.org/show_bug.cgi?id=105202 + */ +static void +handle_absfuzz(struct udev_device *device) +{ + const char *devnode; + struct libevdev *evdev = NULL; + int fd = -1; + int rc; + unsigned int *code; + unsigned int axes[] = {ABS_X, + ABS_Y, + ABS_MT_POSITION_X, + ABS_MT_POSITION_Y}; + + devnode = udev_device_get_devnode(device); + if (!devnode) + goto out; + + fd = open(devnode, O_RDWR); + if (fd == -1 && errno == EACCES) + fd = open(devnode, O_RDONLY); + if (fd < 0) + goto out; + + rc = libevdev_new_from_fd(fd, &evdev); + if (rc != 0) + goto out; + + if (!libevdev_has_event_type(evdev, EV_ABS)) + goto out; + + ARRAY_FOR_EACH(axes, code) { + struct input_absinfo abs; + int fuzz; + + fuzz = libevdev_get_abs_fuzz(evdev, *code); + if (!fuzz) + continue; + + abs = *libevdev_get_abs_info(evdev, *code); + abs.fuzz = 0; + libevdev_kernel_set_abs_info(evdev, *code, &abs); + + printf("LIBINPUT_FUZZ_%02x=%d\n", *code, fuzz); + } + +out: + close(fd); + libevdev_free(evdev); +} + int main(int argc, char **argv) { int rc = 1; @@ -127,6 +183,8 @@ int main(int argc, char **argv) if (!device) goto out; + handle_absfuzz(device); + if (prop_value(device, "ID_INPUT_TOUCHPAD")) handle_touchpad(device); -- cgit v1.2.1