HID: lenovo: Hide middle-button press until release

Don't relay a middle button press to userspace until release, and then
only if there was no scroll events inbetween. This is closer to what
Xorg's wheel emulation does, and avoids spurious middle-click pastes.

Signed-off-by: Jamie Lentin <jm@lentin.co.uk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 50 insertions, 0 deletions

diff --git a/drivers/hid/hid-lenovo.c b/drivers/hid/hid-lenovo.c
index d40221d78188..e4bc6cb6d7fa 100644
--- a/drivers/hid/hid-lenovo.c
+++ b/drivers/hid/hid-lenovo.c
@@ -37,6 +37,7 @@ struct lenovo_drvdata_tpkbd {
 };
 
 struct lenovo_drvdata_cptkbd {
+        u8 middlebutton_state; /* 0:Up, 1:Down (undecided), 2:Scrolling */
         bool fn_lock;
         int sensitivity;
 };
@@ -316,6 +317,53 @@ static int lenovo_raw_event(struct hid_device *hdev,
         return 0;
 }
 
+static int lenovo_event_cptkbd(struct hid_device *hdev,
+                struct hid_field *field, struct hid_usage *usage, __s32 value)
+{
+        struct lenovo_drvdata_cptkbd *cptkbd_data = hid_get_drvdata(hdev);
+
+        /* "wheel" scroll events */
+        if (usage->type == EV_REL && (usage->code == REL_WHEEL ||
+                        usage->code == REL_HWHEEL)) {
+                /* Scroll events disable middle-click event */
+                cptkbd_data->middlebutton_state = 2;
+                return 0;
+        }
+
+        /* Middle click events */
+        if (usage->type == EV_KEY && usage->code == BTN_MIDDLE) {
+                if (value == 1) {
+                        cptkbd_data->middlebutton_state = 1;
+                } else if (value == 0) {
+                        if (cptkbd_data->middlebutton_state == 1) {
+                                /* No scrolling inbetween, send middle-click */
+                                input_event(field->hidinput->input,
+                                        EV_KEY, BTN_MIDDLE, 1);
+                                input_sync(field->hidinput->input);
+                                input_event(field->hidinput->input,
+                                        EV_KEY, BTN_MIDDLE, 0);
+                                input_sync(field->hidinput->input);
+                        }
+                        cptkbd_data->middlebutton_state = 0;
+                }
+                return 1;
+        }
+
+        return 0;
+}
+
+static int lenovo_event(struct hid_device *hdev, struct hid_field *field,
+                struct hid_usage *usage, __s32 value)
+{
+        switch (hdev->product) {
+        case USB_DEVICE_ID_LENOVO_CUSBKBD:
+        case USB_DEVICE_ID_LENOVO_CBTKBD:
+                return lenovo_event_cptkbd(hdev, field, usage, value);
+        default:
+                return 0;
+        }
+}
+
 static int lenovo_features_set_tpkbd(struct hid_device *hdev)
 {
         struct hid_report *report;
@@ -708,6 +756,7 @@ static int lenovo_probe_cptkbd(struct hid_device *hdev)
                 hid_warn(hdev, "Failed to switch middle button: %d\n", ret);
 
         /* Set keyboard settings to known state */
+        cptkbd_data->middlebutton_state = 0;
         cptkbd_data->fn_lock = true;
         cptkbd_data->sensitivity = 0x05;
         lenovo_features_set_cptkbd(hdev);
@@ -835,6 +884,7 @@ static struct hid_driver lenovo_driver = {
         .probe = lenovo_probe,
         .remove = lenovo_remove,
         .raw_event = lenovo_raw_event,
+        .event = lenovo_event,
         .report_fixup = lenovo_report_fixup,
 };
 module_hid_driver(lenovo_driver);