[~/src/openwrt]$ ./build.sh
make: Entering directory `/home/matteo/src/openwrt/build_mipsel/linux-2.6-ar7/linux-2.6.21.1'
  CHK     include/linux/version.h
  CHK     include/linux/utsrelease.h
  CHK     include/linux/compile.h
  CC      arch/mips/ar7/platform.o
  CC      arch/mips/ar7/gpio.o
arch/mips/ar7/gpio.c:29:18: error: gpio.h: No such file or directory
arch/mips/ar7/gpio.c:31: error: 'AR7_GPIO_MAX' undeclared here (not in a function)
make[1]: *** [arch/mips/ar7/gpio.o] Error 1
make[1]: *** Waiting for unfinished jobs....
arch/mips/ar7/platform.c:34:18: error: gpio.h: No such file or directory
arch/mips/ar7/platform.c: In function 'vlynq_on':
arch/mips/ar7/platform.c:49: warning: implicit declaration of function 'gpio_request'
arch/mips/ar7/platform.c:54: warning: implicit declaration of function 'ar7_gpio_disable'
arch/mips/ar7/platform.c:57: warning: implicit declaration of function 'ar7_gpio_enable'
arch/mips/ar7/platform.c:60: warning: implicit declaration of function 'gpio_direction_output'
arch/mips/ar7/platform.c:63: warning: implicit declaration of function 'gpio_set_value'
arch/mips/ar7/platform.c:75: warning: implicit declaration of function 'gpio_free'
make[1]: *** [arch/mips/ar7/platform.o] Error 1
make: *** [arch/mips/ar7] Error 2
make: *** Waiting for unfinished jobs....
make: Leaving directory `/home/matteo/src/openwrt/build_mipsel/linux-2.6-ar7/linux-2.6.21.1'