Re: [PATCH v2 2/3] auxdisplay: ht16k33: rework input device initialization

From: Robin van der Gracht
Date: Fri Feb 10 2017 - 03:33:32 EST


On Thu, 9 Feb 2017 10:15:52 -0800
Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote:

> This patch fixes following issues in input device (keypad) handling:
>
> - requesting IRQ before allocating and initializing parts of the device
> that can be referenced from IRQ handler is racy, even if we try to
> disable interrupt after requesting it. Let's move allocations around
> so that everything is ready by the time we request IRQ.
>
> - using threaded interrupt handler to schedule a work item it sub-optimal.
> Disabling and then re-enabling interrupts in work item and in open/close
> methods is prone to races and exactly the reason theraded interrupts were
> introduced. Let's use the infrastructure properly and keep scanning the
> matrix array in IRQ thread, stopping when there are no keys, or when told
> to do so.
>
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> ---
>
> v2: addressed Robin's feedback - changed interrupt trigger from
> IRQF_TRIGGER_RISING to IRQF_TRIGGER_HIGH
>

Works like a charm!

Tested-by: Robin van der Gracht <robin@xxxxxxxxxxx>