[openwrt/openwrt] zbt-wd323: add GPIO WDT support

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch openwrt-23.05:
https://git.openwrt.org/fbb4aac69bde73051f95d3ebc9a10a8feb8fdfd9

commit fbb4aac69bde73051f95d3ebc9a10a8feb8fdfd9
Author: Joshua O'Leary <josh.oleary at mobile-power.co.uk>
AuthorDate: Wed Jun 7 11:32:22 2023 +0100

    zbt-wd323: add GPIO WDT support
    
    Watchdog has not been properly configured for this router - the PCB has a
    hardware watchdog connected to one of the GPIO pin 21 [1]
    This commit provides this fix [2]
    
    Without this fix, the ZBT-WD323 is unusable in OpenWRT because it power
    cycles every 30 seconds due to the watchdog tripping
    
    [1] https://forum.openwrt.org/t/zbt-wd323-router-power-cycles-every-30-seconds/77535/7
    [2] https://forum.openwrt.org/t/zbt-wd323-images-unusable-proposed-workaround/162145/5
    
    Signed-off-by: Joshua O'Leary <josh.oleary at mobile-power.co.uk>
    (cherry picked from commit 008cc836fe42577af2843730dfefd31b750c7de6)
---
 target/linux/ath79/dts/ar9344_zbtlink_zbt-wd323.dts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/target/linux/ath79/dts/ar9344_zbtlink_zbt-wd323.dts b/target/linux/ath79/dts/ar9344_zbtlink_zbt-wd323.dts
index 8fc21be1dc..8dc1ceb666 100644
--- a/target/linux/ath79/dts/ar9344_zbtlink_zbt-wd323.dts
+++ b/target/linux/ath79/dts/ar9344_zbtlink_zbt-wd323.dts
@@ -59,6 +59,14 @@
 			gpios = <&gpio 22 GPIO_ACTIVE_LOW>;
 		};
 	};
+	
+	watchdog {
+		compatible = "linux,wdt-gpio";
+		gpios = <&gpio 21 GPIO_ACTIVE_HIGH>;
+		hw_algo = "toggle";
+		hw_margin_ms = <30000>;
+		always-running;
+	};
 };
 
 &wdt {