HID: lenovo-tpkbd: remove usb dependency

lenovo tpkbd currently relies on the usb interface number to detect
if it is dealing with the touchpad interface or not.
As the report descriptors of the interface 0 does not contain the
button 3, we can use this to remove the need to check for usb.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-lenovo-tpkbd.c b/drivers/hid/hid-lenovo-tpkbd.c
index 0d9a276..2d25b6c 100644
--- a/drivers/hid/hid-lenovo-tpkbd.c
+++ b/drivers/hid/hid-lenovo-tpkbd.c
@@ -14,11 +14,9 @@
 #include <linux/module.h>
 #include <linux/sysfs.h>
 #include <linux/device.h>
-#include <linux/usb.h>
 #include <linux/hid.h>
 #include <linux/input.h>
 #include <linux/leds.h>
-#include "usbhid/usbhid.h"
 
 #include "hid-ids.h"
 
@@ -41,10 +39,9 @@
 		struct hid_input *hi, struct hid_field *field,
 		struct hid_usage *usage, unsigned long **bit, int *max)
 {
-	struct usbhid_device *uhdev;
-
-	uhdev = (struct usbhid_device *) hdev->driver_data;
-	if (uhdev->ifnum == 1 && usage->hid == (HID_UP_BUTTON | 0x0010)) {
+	if (usage->hid == (HID_UP_BUTTON | 0x0010)) {
+		/* mark the device as pointer */
+		hid_set_drvdata(hdev, (void *)1);
 		map_key_clear(KEY_MICMUTE);
 		return 1;
 	}
@@ -398,7 +395,6 @@
 		const struct hid_device_id *id)
 {
 	int ret;
-	struct usbhid_device *uhdev;
 
 	ret = hid_parse(hdev);
 	if (ret) {
@@ -412,9 +408,8 @@
 		goto err;
 	}
 
-	uhdev = (struct usbhid_device *) hdev->driver_data;
-
-	if (uhdev->ifnum == 1) {
+	if (hid_get_drvdata(hdev)) {
+		hid_set_drvdata(hdev, NULL);
 		ret = tpkbd_probe_tp(hdev);
 		if (ret)
 			goto err_hid;
@@ -442,10 +437,7 @@
 
 static void tpkbd_remove(struct hid_device *hdev)
 {
-	struct usbhid_device *uhdev;
-
-	uhdev = (struct usbhid_device *) hdev->driver_data;
-	if (uhdev->ifnum == 1)
+	if (hid_get_drvdata(hdev))
 		tpkbd_remove_tp(hdev);
 
 	hid_hw_stop(hdev);