HID: hid-multitouch: Switch to device groups

Switch the driver over to device group handling.  By adding the
HID_GROUP_MULTITOUCH group to hid-core, hid-generic will no longer
match multitouch devices.  By adding the HID_GROUP_MULTITOUCH entry to
the device list, hid-multitouch will match all unknown multitouch
devices, and udev will automatically load the module.

Since HID_QUIRK_MULTITOUCH never gets set, the special quirks handling
can be removed.  Since all HID MT devices have HID_DG_CONTACTID, they
can be removed from the hid_have_special_driver list.

With this patch, the unknown device ids are no longer NULL, so the code
is modified to check for the generic entry instead.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Acked-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 19 insertions, 9 deletions

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 1d5b94167b52..ea465f1ceae9 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -635,6 +635,21 @@ static void mt_set_maxcontacts(struct hid_device *hdev)
         }
 }
 
+static void mt_post_parse_default_settings(struct mt_device *td)
+{
+        __s32 quirks = td->mtclass.quirks;
+
+        /* unknown serial device needs special quirks */
+        if (td->touches_by_report == 1) {
+                quirks |= MT_QUIRK_ALWAYS_VALID;
+                quirks &= ~MT_QUIRK_NOT_SEEN_MEANS_UP;
+                quirks &= ~MT_QUIRK_VALID_IS_INRANGE;
+                quirks &= ~MT_QUIRK_VALID_IS_CONFIDENCE;
+        }
+
+        td->mtclass.quirks = quirks;
+}
+
 static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
         int ret, i;
@@ -654,7 +669,6 @@ 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) {
@@ -674,14 +688,8 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
         if (ret)
                 goto fail;
 
-        if (!id && td->touches_by_report == 1) {
-                /* the device has been sent by hid-generic */
-                mtclass = &td->mtclass;
-                mtclass->quirks |= MT_QUIRK_ALWAYS_VALID;
-                mtclass->quirks &= ~MT_QUIRK_NOT_SEEN_MEANS_UP;
-                mtclass->quirks &= ~MT_QUIRK_VALID_IS_INRANGE;
-                mtclass->quirks &= ~MT_QUIRK_VALID_IS_CONFIDENCE;
-        }
+        if (id->vendor == HID_ANY_ID && id->product == HID_ANY_ID)
+                mt_post_parse_default_settings(td);
 
         td->slots = kzalloc(td->maxcontacts * sizeof(struct mt_slot),
                                 GFP_KERNEL);
@@ -999,6 +1007,8 @@ static const struct hid_device_id mt_devices[] = {
                 HID_USB_DEVICE(USB_VENDOR_ID_XIROKU,
                         USB_DEVICE_ID_XIROKU_CSR2) },
 
+        /* Generic MT device */
+        { HID_DEVICE(HID_BUS_ANY, HID_GROUP_MULTITOUCH, HID_ANY_ID, HID_ANY_ID) },
         { }
 };
 MODULE_DEVICE_TABLE(hid, mt_devices);