[PATCH] ARM: dts: allwinner: minimize irq debounce filter per default

From: Andreas Feldner
Date: Mon Feb 06 2023 - 16:47:13 EST


The SoC features debounce logic for external interrupts. Per default,
this is based on a 32kHz oscillator, in effect filtering away multiple
interrupts separated by less than roughly 100µs.

This patch sets different defaults for this filter for this board:
PG is connected to non-mechanical components, without any risk for
showing bounces. PA is mostly exposed to GPIO pins, however the
existence of a debounce filter is undesirable as well if electronic
components are connected.

Additionally, the clock-frequency attribute is added for each of
the 4 cores to eliminate the kernel error message on boot, that
the attribute is missing.

Signed-off-by: Andreas Feldner <pelzi@xxxxxxxxxxxxxxx>
---
.../dts/sun8i-h2-plus-bananapi-m2-zero.dts | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts b/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts
index d729b7c705db..1fc0d5d1e51a 100644
--- a/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts
+++ b/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts
@@ -113,6 +113,22 @@ wifi_pwrseq: wifi_pwrseq {

&cpu0 {
cpu-supply = <&reg_vdd_cpux>;
+ clock-frequency = <1296000000>;
+};
+
+&cpu1 {
+ cpu-supply = <&reg_vdd_cpux>;
+ clock-frequency = <1296000000>;
+};
+
+&cpu2 {
+ cpu-supply = <&reg_vdd_cpux>;
+ clock-frequency = <1296000000>;
+};
+
+&cpu3 {
+ cpu-supply = <&reg_vdd_cpux>;
+ clock-frequency = <1296000000>;
};

&de {
@@ -193,6 +209,8 @@ bluetooth {
};

&pio {
+ /* 1µs debounce filter on both IRQ banks */
+ input-debounce = <1 1>;
gpio-line-names =
/* PA */
"CON2-P13", "CON2-P11", "CON2-P22", "CON2-P15",
--
2.30.2