HID: detect Win 8 multitouch devices in core

[~andy/linux] / drivers / hid / hid-core.c

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index ddd95f3e33c06a09a949350218ad7e4f62e27cfe..660dce9641626a2b2361e78777143415d59b911e 100644 (file)
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -685,6 +685,13 @@ static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
                hid->group = HID_GROUP_MULTITOUCH;
 }
 
+static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
+{
+       if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
+           parser->global.report_size == 8)
+               parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
+}
+
 static void hid_scan_collection(struct hid_parser *parser, unsigned type)
 {
        struct hid_device *hid = parser->device;
@@ -714,6 +721,8 @@ static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
        case HID_MAIN_ITEM_TAG_OUTPUT:
                break;
        case HID_MAIN_ITEM_TAG_FEATURE:
+               for (i = 0; i < parser->local.usage_index; i++)
+                       hid_scan_feature_usage(parser, parser->local.usage[i]);
                break;
        }
 
@@ -757,6 +766,13 @@ static int hid_scan_report(struct hid_device *hid)
        while ((start = fetch_item(start, end, &item)) != NULL)
                dispatch_type[item.type](parser, &item);
 
+       /*
+        * Handle special flags set during scanning.
+        */
+       if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) &&
+           (hid->group == HID_GROUP_MULTITOUCH))
+               hid->group = HID_GROUP_MULTITOUCH_WIN_8;
+
        vfree(parser);
        return 0;
 }