From be6e2b5734a425941fcdcdbd2a9337be498ce2cf Mon Sep 17 00:00:00 2001 From: Andri Yngvason Date: Wed, 7 Sep 2022 15:01:59 +0000 Subject: [PATCH] HID: multitouch: Add memory barriers This fixes broken atomic checks which cause a race between the release-timer and processing of hid input. I noticed that contacts were sometimes sticking, even with the "sticky fingers" quirk enabled. This fixes that problem. Cc: stable@vger.kernel.org Fixes: 9609827458c3 ("HID: multitouch: optimize the sticky fingers timer") Signed-off-by: Andri Yngvason Signed-off-by: Benjamin Tissoires Link: https://lore.kernel.org/r/20220907150159.2285460-1-andri@yngvason.is --- drivers/hid/hid-multitouch.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 2e72922e36f5..91a4d3fc30e0 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -1186,7 +1186,7 @@ static void mt_touch_report(struct hid_device *hid, int contact_count = -1; /* sticky fingers release in progress, abort */ - if (test_and_set_bit(MT_IO_FLAGS_RUNNING, &td->mt_io_flags)) + if (test_and_set_bit_lock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags)) return; scantime = *app->scantime; @@ -1267,7 +1267,7 @@ static void mt_touch_report(struct hid_device *hid, del_timer(&td->release_timer); } - clear_bit(MT_IO_FLAGS_RUNNING, &td->mt_io_flags); + clear_bit_unlock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags); } static int mt_touch_input_configured(struct hid_device *hdev, @@ -1699,11 +1699,11 @@ static void mt_expired_timeout(struct timer_list *t) * An input report came in just before we release the sticky fingers, * it will take care of the sticky fingers. */ - if (test_and_set_bit(MT_IO_FLAGS_RUNNING, &td->mt_io_flags)) + if (test_and_set_bit_lock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags)) return; if (test_bit(MT_IO_FLAGS_PENDING_SLOTS, &td->mt_io_flags)) mt_release_contacts(hdev); - clear_bit(MT_IO_FLAGS_RUNNING, &td->mt_io_flags); + clear_bit_unlock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags); } static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)