From e24d0d399b2fce71b627043e900ef28283850482 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Mon, 31 Mar 2014 13:27:10 -0400 Subject: [PATCH] HID: core: do not scan constant input report The Microsoft Surface Type/Touch Cover 2 is a fancy device which advertised itself as a multitouch device but with constant input reports. This way, hid_scan_report() gives the group MULTITOUCH to it, but hid-multitouch can not handle it due to the constant collection ignored by hid-input. To prevent such crap in the future, and while we do not fix this particular device, make the scan_report coherent with hid-input.c, and ignore constant input reports. CC: stable@vger.kernel.org # 3.12+ Signed-off-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 3f488ff88e0c..10a2c0866459 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -718,6 +718,9 @@ static int hid_scan_main(struct hid_parser *parser, struct hid_item *item) case HID_MAIN_ITEM_TAG_END_COLLECTION: break; case HID_MAIN_ITEM_TAG_INPUT: + /* ignore constant inputs, they will be ignored by hid-input */ + if (data & HID_MAIN_ITEM_CONSTANT) + break; for (i = 0; i < parser->local.usage_index; i++) hid_scan_input_usage(parser, parser->local.usage[i]); break; -- 2.20.1