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HID: input: move up out-of-range processing of input values

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It actually makes sense to clamp the value to its boundaries before
doing further processing.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <ping.cheng@wacom.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Benjamin Tissoires 2022-02-03 15:32:20 +01:00 committed by Jiri Kosina
parent f2d4ddfa64
commit 187ccd6caa
1 changed files with 24 additions and 24 deletions
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48
drivers/hid/hid-input.c
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@ -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