Re: [PATCH v3 4/4] pinctrl: samsung: Add filter selection support for alive bank on gs101
From: André Draszik
Date: Thu Mar 06 2025 - 16:24:55 EST
On Thu, 2025-03-06 at 20:42 +0000, Peter Griffin wrote:
> Newer Exynos based SoCs have a filter selection bitfield in the filter
> configuration registers on alive bank pins. This allows the selection of
> a digital or analog delay filter for each pin. Add support for selecting
> and enabling the filter.
>
> On suspend we set the analog filter to all pins in the bank (as the
> digital filter relies on a clock). On resume the digital filter is
> reapplied to all pins in the bank. The digital filter is working via
> a clock and has an adjustable filter delay flt_width bitfield, whereas
> the analog filter uses a fixed delay.
>
> The filter determines to what extent signal fluctuations received through
> the pad are considered glitches.
>
> The code path can be exercised using
> echo mem > /sys/power/state
> And then wake the device using a eint gpio
>
> Signed-off-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
Reviewed-by: André Draszik <andre.draszik@xxxxxxxxxx>