From 187ccd6caa4b40dcfbcb2531746e9fe500414e79 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Thu, 3 Feb 2022 15:32:20 +0100 Subject: HID: input: move up out-of-range processing of input values It actually makes sense to clamp the value to its boundaries before doing further processing. Signed-off-by: Benjamin Tissoires Reviewed-by: Ping Cheng Acked-by: Peter Hutterer Signed-off-by: Jiri Kosina --- drivers/hid/hid-input.c | 48 ++++++++++++++++++++++++------------------------ 1 file changed, 24 insertions(+), 24 deletions(-) (limited to 'drivers/hid/hid-input.c') diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 54b3e9c5ccc4..8770d9a2b2af 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -1364,6 +1364,30 @@ void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct return; } + /* + * Ignore out-of-range values as per HID specification, + * section 5.10 and 6.2.25, when NULL state bit is present. + * When it's not, clamp the value to match Microsoft's input + * driver as mentioned in "Required HID usages for digitizers": + * https://msdn.microsoft.com/en-us/library/windows/hardware/dn672278(v=vs.85).asp + * + * The logical_minimum < logical_maximum check is done so that we + * don't unintentionally discard values sent by devices which + * don't specify logical min and max. + */ + if ((field->flags & HID_MAIN_ITEM_VARIABLE) && + field->logical_minimum < field->logical_maximum) { + if (field->flags & HID_MAIN_ITEM_NULL_STATE && + (value < field->logical_minimum || + value > field->logical_maximum)) { + dbg_hid("Ignoring out-of-range value %x\n", value); + return; + } + value = clamp(value, + field->logical_minimum, + field->logical_maximum); + } + switch (usage->hid) { case HID_DG_INVERT: *quirks = value ? (*quirks | HID_QUIRK_INVERT) : (*quirks & ~HID_QUIRK_INVERT); @@ -1431,30 +1455,6 @@ void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct break; } - /* - * Ignore out-of-range values as per HID specification, - * section 5.10 and 6.2.25, when NULL state bit is present. - * When it's not, clamp the value to match Microsoft's input - * driver as mentioned in "Required HID usages for digitizers": - * https://msdn.microsoft.com/en-us/library/windows/hardware/dn672278(v=vs.85).asp - * - * The logical_minimum < logical_maximum check is done so that we - * don't unintentionally discard values sent by devices which - * don't specify logical min and max. - */ - if ((field->flags & HID_MAIN_ITEM_VARIABLE) && - (field->logical_minimum < field->logical_maximum)) { - if (field->flags & HID_MAIN_ITEM_NULL_STATE && - (value < field->logical_minimum || - value > field->logical_maximum)) { - dbg_hid("Ignoring out-of-range value %x\n", value); - return; - } - value = clamp(value, - field->logical_minimum, - field->logical_maximum); - } - /* * Ignore reports for absolute data if the data didn't change. This is * not only an optimization but also fixes 'dead' key reports. Some -- cgit v1.2.3