HID: fix unit exponent parsing
HID spec details special values for the HID field unit exponent.
Basically, the range [0x8..0xf] correspond to [-8..-1], so this is
a standard two's complement on a half-byte.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/include/linux/hid.h b/include/linux/hid.h
index c6bef8f..4161bf2 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -717,6 +717,7 @@
void hid_disconnect(struct hid_device *hid);
const struct hid_device_id *hid_match_id(struct hid_device *hdev,
const struct hid_device_id *id);
+s32 hid_snto32(__u32 value, unsigned n);
/**
* hid_map_usage - map usage input bits