[PATCH v3.9+] HID: multitouch: fix touchpad buttons

From: Benjamin Tissoires
Date: Fri Mar 22 2013 - 13:54:54 EST

Commit "HID: multitouch: use the callback "report" instead..." breaks the
buttons of touchpads following the HID multitouch specification.
The buttons were emmitted through hid-input, but as now the events
are generated only in hid-multitouch, the buttons are not emmitted anymore.

The input_event() call is far much simpler than the hid-input one as
many of the different tests do not apply to multitouch touchpads.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>

Hi guys,

really sorry for that. I forgot that I had in one of my drawer of my desk one
prototype of a touchpad following the multitouch specification, but with
two physical buttons. And of course, I did not put it in my database, meaning
that the support has been broken in the patches already in 3.9.

I don't think it's a big deal (to my knowledge, no retail product uses this
feature), but it's still a regression in 3.9.


drivers/hid/hid-multitouch.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 1f544a4..7d72379 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -620,6 +620,7 @@ static void mt_process_mt_event(struct hid_device *hid, struct hid_field *field,
struct mt_device *td = hid_get_drvdata(hid);
__s32 quirks = td->mtclass.quirks;
+ struct input_dev *input = field->hidinput->input;

if (hid->claimed & HID_CLAIMED_INPUT) {
switch (usage->hid) {
@@ -669,13 +670,16 @@ static void mt_process_mt_event(struct hid_device *hid, struct hid_field *field,

+ if (usage->type)
+ input_event(input, usage->type, usage->code,
+ value);

if (usage->usage_index + 1 == field->report_count) {
/* we only take into account the last report. */
if (usage->hid == td->last_slot_field)
- mt_complete_slot(td, field->hidinput->input);
+ mt_complete_slot(td, input);


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