4.3-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jason Gerecke <[email protected]> commit df7079380554e6e8e13a0812c7e6c72f669aba5c upstream. When introduced in commit 1b5d514, the check 'if (hid_data->cc_index >= 0)' in 'wacom_wac_finger_pre_report' was intended to switch where the driver got the expected number of contacts from: HID_DG_CONTACTCOUNT if the usage was present, or 'touch_max' otherwise. Unfortunately, an oversight worthy of a brown paper bag (specifically, that 'cc_index' could never be negative) meant that the latter 'else' clause would never be entered. The patch prior to this one introduced a way for 'cc_index' to be negative, but only if HID_DG_CONTACTCOUNT is present in some report _other_ than the one being processed. To ensure the 'else' clause is also entered for devices which don't have HID_DG_CONTACTCOUNT on _any_ report, we add the additional constraint that 'cc_report' be non-zero (which is true only if the usage is present in some report). Signed-off-by: Jason Gerecke <[email protected]> Signed-off-by: Jiri Kosina <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/hid/wacom_wac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -1740,8 +1740,8 @@ static void wacom_wac_finger_pre_report( } } } - - if (hid_data->cc_index >= 0) { + if (hid_data->cc_report != 0 && + hid_data->cc_index >= 0) { struct hid_field *field = report->field[hid_data->cc_index]; int value = field->value[hid_data->cc_value_index]; if (value)
