[PATCH libinput] evdev: use the udev ID_INPUT_POINTINGSTICK property

[Hans de Goede]

Hi,

On 29-05-15 17:06, Benjamin Tissoires wrote:
>
>
> On 05/29/2015 03:31 AM, Hans de Goede wrote:
>> Hi,
>>
>> On 29-05-15 03:28, Peter Hutterer wrote:
>>> Added in systemd 220, but note that for udev backwards compatibility, the
>>> ID_INPUT_POINTINGSTICK tag is set in addition to the ID_INPUT_MOUSE tag.
>>>
>>> And use that property to tag a device as trackpoint too, this allows
>>> temporary
>>> workarounds for kernel bugs where the input prop isn't set yet.
>>>
>>> https://bugzilla.redhat.com/show_bug.cgi?id=1225563
>>>
>>> Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
>>
>> LGTM: Reviewed-by: Hans de Goede <hdegoede at redhat.com>
>>
>
> Yep, as Hans said, this looks good to me (it's already push, so that
> does not matter that much).
>
> However, for completeness, if we want to be able to override the
> INPUT_PROP_POINTING_STICK property, we also need the following patch:
>
>
>  From 9573bfb574a74e2eea89a9227aaf67c1c9403983 Mon Sep 17 00:00:00 2001
> From: Benjamin Tissoires <benjamin.tissoires at gmail.com>
> Date: Fri, 29 May 2015 11:02:12 -0400
> Subject: [PATCH] evdev: remove direct checks for INPUT_PROP_POINTING_STICK
>
> If we need to temporary override a device with ID_INPUT_POINTINGSTICK,
> evdev sets the tag EVDEV_TAG_TRACKPOINT to the device. Rely on the tag
> to behave properly for scroll emulation.
>
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires at gmail.com>

Hmm, IIRC some of these code-paths run before the tags get set,
so this will not work. Did you check for this?

Regards,

Hans


> ---
>   src/evdev.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/src/evdev.c b/src/evdev.c
> index 642f441..a996bcf 100644
> --- a/src/evdev.c
> +++ b/src/evdev.c
> @@ -1070,7 +1070,7 @@ evdev_scroll_get_default_method(struct libinput_device *device)
>   {
>   	struct evdev_device *evdev = (struct evdev_device *)device;
>
> -	if (libevdev_has_property(evdev->evdev, INPUT_PROP_POINTING_STICK))
> +	if (evdev->tags & EVDEV_TAG_TRACKPOINT)
>   		return LIBINPUT_CONFIG_SCROLL_ON_BUTTON_DOWN;
>
>   	/* Mice without a scroll wheel but with middle button have on-button
> @@ -1110,7 +1110,7 @@ evdev_scroll_get_default_button(struct libinput_device *device)
>   {
>   	struct evdev_device *evdev = (struct evdev_device *)device;
>
> -	if (libevdev_has_property(evdev->evdev, INPUT_PROP_POINTING_STICK))
> +	if (evdev->tags & EVDEV_TAG_TRACKPOINT)
>   		return BTN_MIDDLE;
>
>   	/* A device that defaults to button scrolling defaults
> @@ -1505,7 +1505,7 @@ evdev_read_dpi_prop(struct evdev_device *device)
>   	 * POINTINGSTICK_CONST_ACCEL value to compensate for sensitivity
>   	 * differences between models, we translate this to a fake dpi.
>   	 */
> -	if (libevdev_has_property(device->evdev, INPUT_PROP_POINTING_STICK))
> +	if (device->tags & EVDEV_TAG_TRACKPOINT)
>   		return evdev_get_trackpoint_dpi(device);
>
>   	mouse_dpi = udev_device_get_property_value(device->udev_device,
>