HID: handle all multitouch devices through hid-multitouch

When the quirk HID_QUIRK_MULTITOUCH is present and when hid-multitouch
is loaded, let's pass the device to hid-multitouch even if it has
not been registered in hid-multitouch.

If any other driver wants to take precedence over hid-multitouch,
the usual way of adding it to hid_have_special_driver will work as
the quirk HID_QUIRK_MULTITOUCH won't be set by the generic hid layer.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 7 insertions, 4 deletions

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 2088ab4e5db5..a61ba42e1bff 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -637,10 +637,12 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
         struct mt_device *td;
         struct mt_class *mtclass = mt_classes; /* MT_CLS_DEFAULT */
 
-        for (i = 0; mt_classes[i].name ; i++) {
-                if (id->driver_data == mt_classes[i].name) {
-                        mtclass = &(mt_classes[i]);
-                        break;
+        if (id) {
+                for (i = 0; mt_classes[i].name ; i++) {
+                        if (id->driver_data == mt_classes[i].name) {
+                                mtclass = &(mt_classes[i]);
+                                break;
+                        }
                 }
         }
 
@@ -648,6 +650,7 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
          * that emit events over several HID messages.
          */
         hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC;
+        hdev->quirks &= ~HID_QUIRK_MULTITOUCH;
 
         td = kzalloc(sizeof(struct mt_device), GFP_KERNEL);
         if (!td) {