Input: introduce device properties

Today, userspace sets up an input device based on the data it emits.
This is not always enough; a tablet and a touchscreen may emit exactly
the same data, for instance, but the former should be set up with a
pointer whereas the latter does not need to. Recently, a new type of
touchpad has emerged where the buttons are under the pad, which
changes logic without changing the emitted data. This patch introduces
a new ioctl, EVIOCGPROP, which enables user access to a set of device
properties useful during setup. The properties are given as a bitmap
in the same fashion as the event types, and are also made available
via sysfs, uevent and /proc/bus/input/devices.

Acked-by: Ping Cheng <pingc@wacom.com>
Acked-by: Chase Douglas <chase.douglas@canonical.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
This commit is contained in:
Henrik Rydberg 2010-12-18 20:51:13 +01:00
parent 4dd295a73e
commit 85b7720039
5 changed files with 44 additions and 0 deletions

View file

@ -677,6 +677,10 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
#define EVIOC_MASK_SIZE(nr) ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT))
switch (EVIOC_MASK_SIZE(cmd)) {
case EVIOCGPROP(0):
return bits_to_user(dev->propbit, INPUT_PROP_MAX,
size, p, compat_mode);
case EVIOCGKEY(0):
return bits_to_user(dev->key, KEY_MAX, size, p, compat_mode);