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| author | Benjamin Tissoires <benjamin.tissoires@redhat.com> | 2019-05-21 15:38:31 +0200 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2019-05-22 12:37:37 +0200 |
| commit | 81bcbad53bab4bf9f200eda303d7a05cdb9bd73b (patch) | |
| tree | 76314d947dd582c731813e161c439315c98e7d95 | |
| parent | 69dbdfffef20c715df9f381b2cee4e9e0a4efd93 (diff) | |
| download | linux-81bcbad53bab4bf9f200eda303d7a05cdb9bd73b.tar.bz2 | |
HID: multitouch: handle faulty Elo touch device
Since kernel v5.0, one single win8 touchscreen device failed.
And it turns out this is because it reports 2 InRange usage per touch.
It's a first, and I *really* wonder how this was allowed by Microsoft in
the first place. But IIRC, Breno told me this happened *after* a firmware
upgrade...
Anyway, better be safe for those crappy devices, and make sure we have
a full slot before jumping to the next.
This won't prevent all crappy devices to fail here, but at least we will
have a safeguard as long as the contact ID and the X and Y coordinates
are placed in the report after the grabage.
Fixes: 01eaac7e5713 ("HID: multitouch: remove one copy of values")
CC: stable@vger.kernel.org # v5.0+
Reported-and-tested-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| -rw-r--r-- | drivers/hid/hid-multitouch.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index c02d4cad1893..1565a307170a 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -641,6 +641,13 @@ static void mt_store_field(struct hid_device *hdev, if (*target != DEFAULT_TRUE && *target != DEFAULT_FALSE && *target != DEFAULT_ZERO) { + if (usage->contactid == DEFAULT_ZERO || + usage->x == DEFAULT_ZERO || + usage->y == DEFAULT_ZERO) { + hid_dbg(hdev, + "ignoring duplicate usage on incomplete"); + return; + } usage = mt_allocate_usage(hdev, application); if (!usage) return; |