[PATCH 5.9 42/46] Input: atmel_mxt_ts - fix lost interrupts

From: Greg Kroah-Hartman
Date: Sun Dec 06 2020 - 06:46:09 EST


From: Linus Walleij <linus.walleij@xxxxxxxxxx>

commit 8c3b55a299c325830a987de21dab6a89ecb71164 upstream.

After commit 74d905d2d38a devices requiring the workaround for edge
triggered interrupts stopped working.

The hardware needs the quirk to be used before even proceeding to
check if the quirk is needed because mxt_acquire_irq() is called
before mxt_check_retrigen() is called and at this point pending IRQs
need to be checked, and if the workaround is not active, all
interrupts will be lost from this point.

Solve this by switching the calls around.

Reported-by: Andre Müller <andre.muller@xxxxxx>
Tested-by: Andre Müller <andre.muller@xxxxxx>
Suggested-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Fixes: 74d905d2d38a ("Input: atmel_mxt_ts - only read messages in mxt_acquire_irq() when necessary")
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20201201123026.1416743-1-linus.walleij@xxxxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/input/touchscreen/atmel_mxt_ts.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -2183,11 +2183,11 @@ static int mxt_initialize(struct mxt_dat
msleep(MXT_FW_RESET_TIME);
}

- error = mxt_acquire_irq(data);
+ error = mxt_check_retrigen(data);
if (error)
return error;

- error = mxt_check_retrigen(data);
+ error = mxt_acquire_irq(data);
if (error)
return error;