HID: bring back possibility to specify vid/pid ignore on module load

When hid quirks were converted to specialized driver, the HID_QUIRK_IGNORE
has been moved completely, as the hid_ignore_list[] has been moved into the
generic code.

However userspace already got used to the possibility that modprobing
usbhid with

	'quirks=vid:pid:0x4'

makes the device ignored by usbhid driver. So keep this quirk flag in place
for backwards compatibility.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/usbhid/hid-core.c

@@ -711,6 +711,9 @@ static int usbhid_parse(struct hid_device *hid)
 	quirks = usbhid_lookup_quirk(le16_to_cpu(dev->descriptor.idVendor),
 			le16_to_cpu(dev->descriptor.idProduct));
 
+	if (quirks & HID_QUIRK_IGNORE)
+		return -ENODEV;
+
 	/* Many keyboards and mice don't like to be polled for reports,
 	 * so we will always set the HID_QUIRK_NOGET flag for them. */
 	if (interface->desc.bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {

include/linux/hid.h

@@ -270,6 +270,7 @@ struct hid_item {
 
 #define HID_QUIRK_INVERT			0x00000001
 #define HID_QUIRK_NOTOUCH			0x00000002
+#define HID_QUIRK_IGNORE			0x00000004
 #define HID_QUIRK_NOGET				0x00000008
 #define HID_QUIRK_BADPAD			0x00000020
 #define HID_QUIRK_MULTI_INPUT			0x00000040