[PATCH] Input: joydev - extend absolute mouse detection

From: Alexander Tsoy
Date: Sun Jun 23 2019 - 23:08:36 EST


Extend event signature matching to catch more input devices emulated by
BMC firmwares, QEMU and VMware.

Signed-off-by: Alexander Tsoy <alexander@xxxxxxx>
---
drivers/input/joydev.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c
index ac21c050fdb0..a2b5fbba2d3b 100644
--- a/drivers/input/joydev.c
+++ b/drivers/input/joydev.c
@@ -808,6 +808,7 @@ static bool joydev_dev_is_blacklisted(struct input_dev *dev)
static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
{
DECLARE_BITMAP(jd_scratch, KEY_CNT);
+ bool ev_match = false;

BUILD_BUG_ON(ABS_CNT > KEY_CNT || EV_CNT > KEY_CNT);

@@ -826,17 +827,36 @@ static bool joydev_dev_is_absolute_mouse(struct input_dev *dev)
* considered to be an absolute mouse if the following is
* true:
*
- * 1) Event types are exactly EV_ABS, EV_KEY and EV_SYN.
+ * 1) Event types are exactly
+ * EV_ABS, EV_KEY and EV_SYN
+ * or
+ * EV_ABS, EV_KEY, EV_SYN and EV_MSC
+ * or
+ * EV_ABS, EV_KEY, EV_SYN, EV_MSC and EV_REL.
* 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);
+ /* VMware VMMouse, HP ILO2 */
__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))
+ if (bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
+ ev_match = true;
+
+ /* HP ILO2, AMI BMC firmware */
+ __set_bit(EV_MSC, jd_scratch);
+ if (bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
+ ev_match = true;
+
+ /* VMware Virtual USB Mouse, QEMU USB Tablet, ATEN BMC firmware */
+ __set_bit(EV_REL, jd_scratch);
+ if (bitmap_equal(jd_scratch, dev->evbit, EV_CNT))
+ ev_match = true;
+
+ if (!ev_match)
return false;

bitmap_zero(jd_scratch, ABS_CNT);
--
2.21.0