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-rw-r--r--drivers/input/joydev.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c
index f362883c94e3..1d247bcf2ae2 100644
--- a/drivers/input/joydev.c
+++ b/drivers/input/joydev.c
@@ -747,6 +747,63 @@ static void joydev_cleanup(struct joydev *joydev)
input_close_device(handle);
}
+static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
+{
+ DECLARE_BITMAP(jd_scratch, KEY_CNT);
+
+ BUILD_BUG_ON(ABS_CNT > KEY_CNT || EV_CNT > KEY_CNT);
+
+ /*
+ * Virtualization (VMware, etc) and remote management (HP
+ * ILO2) solutions use absolute coordinates for their virtual
+ * pointing devices so that there is one-to-one relationship
+ * between pointer position on the host screen and virtual
+ * guest screen, and so their mice use ABS_X, ABS_Y and 3
+ * primary button events. This clashes with what joydev
+ * considers to be joysticks (a device with at minimum ABS_X
+ * axis).
+ *
+ * Here we are trying to separate absolute mice from
+ * joysticks. A device is, for joystick detection purposes,
+ * considered to be an absolute mouse if the following is
+ * true:
+ *
+ * 1) Event types are exactly EV_ABS, EV_KEY and EV_SYN.
+ * 2) Absolute events are exactly ABS_X and ABS_Y.
+ * 3) Keys are exactly BTN_LEFT, BTN_RIGHT and BTN_MIDDLE.
+ * 4) Device is not on "Amiga" bus.
+ */
+
+ bitmap_zero(jd_scratch, EV_CNT);
+ __set_bit(EV_ABS, jd_scratch);
+ __set_bit(EV_KEY, jd_scratch);
+ __set_bit(EV_SYN, jd_scratch);
+ if (!bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
+ return false;
+
+ bitmap_zero(jd_scratch, ABS_CNT);
+ __set_bit(ABS_X, jd_scratch);
+ __set_bit(ABS_Y, jd_scratch);
+ if (!bitmap_equal(dev->absbit, jd_scratch, ABS_CNT))
+ return false;
+
+ bitmap_zero(jd_scratch, KEY_CNT);
+ __set_bit(BTN_LEFT, jd_scratch);
+ __set_bit(BTN_RIGHT, jd_scratch);
+ __set_bit(BTN_MIDDLE, jd_scratch);
+
+ if (!bitmap_equal(dev->keybit, jd_scratch, KEY_CNT))
+ return false;
+
+ /*
+ * Amiga joystick (amijoy) historically uses left/middle/right
+ * button events.
+ */
+ if (dev->id.bustype == BUS_AMIGA)
+ return false;
+
+ return true;
+}
static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
{
@@ -758,6 +815,10 @@ static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
return false;
+ /* Avoid absolute mice */
+ if (joydev_dev_is_absolute_mouse(dev))
+ return false;
+
return true;
}