Watchdog device controlled through GPIO-line

modulename: gpio_wdt.ko

configname: CONFIG_GPIO_WATCHDOG

Linux Kernel Configuration
└─>Device Drivers
└─>Watchdog Timer Support
└─>Watchdog device controlled through GPIO-line
In linux kernel since version 3.14 (release Date: 2014-03-30)  
If you say yes here you get support for watchdog device
controlled through GPIO-line.

source code:
drivers/watchdog/gpio_wdt.c