Input: add INPUT_PROP_POINTING_STICK property

It is useful for userspace to know that there not dealing with a regular
mouse but rather with a pointing stick (e.g. a trackpoint) so that
userspace can e.g. automatically enable middle button scrollwheel
emulation.

It is impossible to tell the difference from the evdev info without
resorting to putting a list of device / driver names in userspace, this is
undesirable.

Add a property which allows userspace to see if a device is a pointing
stick, and set it on all the pointing stick drivers.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

5 files changed, 10 insertions, 0 deletions

diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
index a956b980ee73..9d9e5076d402 100644
--- a/drivers/input/mouse/alps.c
+++ b/drivers/input/mouse/alps.c
@@ -2373,6 +2373,9 @@ int alps_init(struct psmouse *psmouse)
         dev2->keybit[BIT_WORD(BTN_LEFT)] =
                 BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) | BIT_MASK(BTN_RIGHT);
 
+        if (priv->flags & ALPS_DUALPOINT)
+                __set_bit(INPUT_PROP_POINTING_STICK, dev2->propbit);
+
         if (input_register_device(priv->dev2))
                 goto init_fail;
 
diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index d71bd3635de1..0cbf6281899c 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -1614,6 +1614,9 @@ int elantech_init(struct psmouse *psmouse)
                 tp_dev->keybit[BIT_WORD(BTN_LEFT)] =
                         BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) |
                         BIT_MASK(BTN_RIGHT);
+
+                __set_bit(INPUT_PROP_POINTING_STICK, tp_dev->propbit);
+
                 error = input_register_device(etd->tp_dev);
                 if (error < 0)
                         goto init_fail_tp_reg;
diff --git a/drivers/input/mouse/synaptics_usb.c b/drivers/input/mouse/synaptics_usb.c
index e122bda16aab..db3973d78207 100644
--- a/drivers/input/mouse/synaptics_usb.c
+++ b/drivers/input/mouse/synaptics_usb.c
@@ -387,6 +387,7 @@ static int synusb_probe(struct usb_interface *intf,
                 __set_bit(EV_REL, input_dev->evbit);
                 __set_bit(REL_X, input_dev->relbit);
                 __set_bit(REL_Y, input_dev->relbit);
+                __set_bit(INPUT_PROP_POINTING_STICK, input_dev->propbit);
                 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 127, 0, 0);
         } else {
                 input_set_abs_params(input_dev, ABS_X,
diff --git a/drivers/input/mouse/trackpoint.c b/drivers/input/mouse/trackpoint.c
index ca843b6cf6bd..b377462748a2 100644
--- a/drivers/input/mouse/trackpoint.c
+++ b/drivers/input/mouse/trackpoint.c
@@ -393,6 +393,8 @@ int trackpoint_detect(struct psmouse *psmouse, bool set_properties)
         if ((button_info & 0x0f) >= 3)
                 __set_bit(BTN_MIDDLE, psmouse->dev->keybit);
 
+        __set_bit(INPUT_PROP_POINTING_STICK, psmouse->dev->propbit);
+
         trackpoint_defaults(psmouse->private);
 
         error = trackpoint_power_on_reset(&psmouse->ps2dev);
diff --git a/include/uapi/linux/input.h b/include/uapi/linux/input.h
index 19df18c9b8be..1874ebe9ac1e 100644
--- a/include/uapi/linux/input.h
+++ b/include/uapi/linux/input.h
@@ -165,6 +165,7 @@ struct input_keymap_entry {
 #define INPUT_PROP_BUTTONPAD            0x02    /* has button(s) under pad */
 #define INPUT_PROP_SEMI_MT              0x03    /* touch rectangle only */
 #define INPUT_PROP_TOPBUTTONPAD         0x04    /* softbuttons at top of pad */
+#define INPUT_PROP_POINTING_STICK       0x05    /* is a pointing stick */
 
 #define INPUT_PROP_MAX                  0x1f
 #define INPUT_PROP_CNT                  (INPUT_PROP_MAX + 1)