HID: multitouch: Add support for button type usage

According to [1], Windows Precision Touchpad devices must supply
a button type usage in the device capabilities feature report. A
value of 0 indicates that the device contains a depressible
button (i.e. it's a click-pad) whereas a value of 1 indicates
a non-depressible button. Add support for this usage and set
INPUT_PROP_BUTTONPAD on the touchpad input device whenever a
depressible button is present.

[1] https://msdn.microsoft.com/en-us/library/windows/hardware/dn467314(v=vs.85).aspx

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 8bf61d2..4b2a18a 100644 (file)
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -165,6 +165,7 @@ static const struct hid_usage_entry hid_usage_table[] = {
     {0, 0x53, "DeviceIndex"},
     {0, 0x54, "ContactCount"},
     {0, 0x55, "ContactMaximumNumber"},
+    {0, 0x59, "ButtonType"},
     {0, 0x5A, "SecondaryBarrelSwitch"},
     {0, 0x5B, "TransducerSerialNumber"},
   { 15, 0, "PhysicalInterfaceDevice" },

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index ef06dc3..55e89b1 100644 (file)
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -72,6 +72,8 @@ MODULE_LICENSE("GPL");
 #define MT_INPUTMODE_TOUCHSCREEN       0x02
 #define MT_INPUTMODE_TOUCHPAD          0x03
 
+#define MT_BUTTONTYPE_CLICKPAD         0
+
 struct mt_slot {
        __s32 x, y, cx, cy, p, w, h;
        __s32 contactid;        /* the device ContactID assigned to this slot */
@@ -117,6 +119,7 @@ struct mt_device {
                                * 1 means we should use a serial protocol
                                * > 1 means hybrid (multitouch) protocol */
        __u8 buttons_count;     /* number of physical buttons per touchpad */
+       bool is_buttonpad;      /* is this device a button pad? */
        bool serial_maybe;      /* need to check for serial protocol */
        bool curvalid;          /* is the current contact valid? */
        unsigned mt_flags;      /* flags to pass to input-mt */
@@ -334,6 +337,16 @@ static void mt_feature_mapping(struct hid_device *hdev,
                        /* check if the maxcontacts is given by the class */
                        td->maxcontacts = td->mtclass.maxcontacts;
 
+               break;
+       case HID_DG_BUTTONTYPE:
+               if (usage->usage_index >= field->report_count) {
+                       dev_err(&hdev->dev, "HID_DG_BUTTONTYPE out of range\n");
+                       break;
+               }
+
+               if (field->value[usage->usage_index] == MT_BUTTONTYPE_CLICKPAD)
+                       td->is_buttonpad = true;
+
                break;
        }
 }
@@ -735,6 +748,9 @@ static void mt_touch_input_configured(struct hid_device *hdev,
 
        /* check for clickpads */
        if ((td->mt_flags & INPUT_MT_POINTER) && (td->buttons_count == 1))
+               td->is_buttonpad = true;
+
+       if (td->is_buttonpad)
                __set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
 
        input_mt_init_slots(input, td->maxcontacts, td->mt_flags);

diff --git a/include/linux/hid.h b/include/linux/hid.h
index efc7787..f455c38 100644 (file)
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -269,6 +269,7 @@ struct hid_item {
 #define HID_DG_DEVICEINDEX     0x000d0053
 #define HID_DG_CONTACTCOUNT    0x000d0054
 #define HID_DG_CONTACTMAX      0x000d0055
+#define HID_DG_BUTTONTYPE      0x000d0059
 #define HID_DG_BARRELSWITCH2   0x000d005a
 #define HID_DG_TOOLSERIALNUMBER        0x000d005b