CC drivers/input/keyboard/gpio_keys.o /home/ralf/src/linux/linux-mips/drivers/input/keyboard/gpio_keys.c: In function ‘gpio_keys_probe’: /home/ralf/src/linux/linux-mips/drivers/input/keyboard/gpio_keys.c:123: error: implicit declaration of function ‘gpio_request’ /home/ralf/src/linux/linux-mips/drivers/input/keyboard/gpio_keys.c:135: error: implicit declaration of function ‘gpio_free’ make[5]: *** [drivers/input/keyboard/gpio_keys.o] Error 1 make[4]: *** [drivers/input/keyboard] Error 2 make[3]: *** [drivers/input] Error 2 make[2]: *** [drivers] Error 2 make[1]: *** [sub-make] Error 2 Ralf