From: Kerem Karabay <kek...@gmail.com>

This is necessary on Apple Touch Bars, where the tip state is contained
in fields with the HID_DG_TOUCH usage. This feature is gated by a quirk
in order to prevent breaking other devices, see commit c2ef8f21ea8f
("HID: multitouch: add support for trackpads").

Signed-off-by: Kerem Karabay <kek...@gmail.com>
Signed-off-by: Aditya Garg <gargadity...@live.com>
---
 drivers/hid/hid-multitouch.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 3e92789ed..571435da5 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -72,6 +72,7 @@ MODULE_LICENSE("GPL");
 #define MT_QUIRK_FORCE_MULTI_INPUT     BIT(20)
 #define MT_QUIRK_DISABLE_WAKEUP                BIT(21)
 #define MT_QUIRK_ORIENTATION_INVERT    BIT(22)
+#define MT_QUIRK_TOUCH_IS_TIPSTATE     BIT(23)
 
 #define MT_INPUTMODE_TOUCHSCREEN       0x02
 #define MT_INPUTMODE_TOUCHPAD          0x03
@@ -809,6 +810,15 @@ static int mt_touch_input_mapping(struct hid_device *hdev, 
struct hid_input *hi,
 
                        MT_STORE_FIELD(confidence_state);
                        return 1;
+               case HID_DG_TOUCH:
+                       /*
+                        * Legacy devices use TIPSWITCH and not TOUCH.
+                        * Let's just ignore this field unless the quirk is set.
+                        */
+                       if (!(cls->quirks & MT_QUIRK_TOUCH_IS_TIPSTATE))
+                               return -1;
+
+                       fallthrough;
                case HID_DG_TIPSWITCH:
                        if (field->application != HID_GD_SYSTEM_MULTIAXIS)
                                input_set_capability(hi->input,
@@ -872,10 +882,6 @@ static int mt_touch_input_mapping(struct hid_device *hdev, 
struct hid_input *hi,
                case HID_DG_CONTACTMAX:
                        /* contact max are global to the report */
                        return -1;
-               case HID_DG_TOUCH:
-                       /* Legacy devices use TIPSWITCH and not TOUCH.
-                        * Let's just ignore this field. */
-                       return -1;
                }
                /* let hid-input decide for the others */
                return 0;
-- 
2.43.0

Reply via email to