kernelconfig_penguin
default or selected kernelversion does not have config value CONFIG_AR600x_DEBUG_UART_TX_PIN.
Result is shown for kernelversion 3.1.9

GPIO

configname: CONFIG_AR600x_DEBUG_UART_TX_PIN

Linux Kernel Configuration
└─> Device Drivers
└─> Staging drivers
└─> GPIO

WLAN GPIO to be used for Debug UART (Tx)