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>
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index e3f7fc6..0cd97e8 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -677,6 +677,10 @@
#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);
diff --git a/drivers/input/input.c b/drivers/input/input.c
index 37708d1..9ea713f 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -1095,6 +1095,8 @@
seq_printf(seq, "%s ", handle->name);
seq_putc(seq, '\n');
+ input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
+
input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
if (test_bit(EV_KEY, dev->evbit))
input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
@@ -1318,11 +1320,26 @@
}
static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
+static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
+ int max, int add_cr);
+
+static ssize_t input_dev_show_properties(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct input_dev *input_dev = to_input_dev(dev);
+ int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
+ INPUT_PROP_MAX, true);
+ return min_t(int, len, PAGE_SIZE);
+}
+static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
+
static struct attribute *input_dev_attrs[] = {
&dev_attr_name.attr,
&dev_attr_phys.attr,
&dev_attr_uniq.attr,
&dev_attr_modalias.attr,
+ &dev_attr_properties.attr,
NULL
};
@@ -1522,6 +1539,8 @@
if (dev->uniq)
INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
+ INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
+
INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
if (test_bit(EV_KEY, dev->evbit))
INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index bea8972..82542a1 100644
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -680,6 +680,10 @@
retval = uinput_set_bit(arg, swbit, SW_MAX);
break;
+ case UI_SET_PROPBIT:
+ retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
+ break;
+
case UI_SET_PHYS:
if (udev->state == UIST_CREATED) {
retval = -EINVAL;
