Error after adding support for PIO BUTTON for nios 2

Im trying to add the pio buttons driver for the DE2 board , but after doing

>make menuconfig and check support for PIO BUTTON , after that the compilation of kernel fails giving this error :

drivers/char/altera_pio_button.o

/media/disk/nios2-linux/linux-2.6/drivers/char/altera_pio_button.c:20:35: linux/devfs_fs_kernel.h: No such file or directory

/media/disk/nios2-linux/linux-2.6/drivers/char/altera_pio_button.c:87: warning: initialization from incompatible pointer type

/media/disk/nios2-linux/linux-2.6/drivers/char/altera_pio_button.c: In function `button_start':

/media/disk/nios2-linux/linux-2.6/drivers/char/altera_pio_button.c:113: error: `SA_INTERRUPT' undeclared (first use in this function)

/media/disk/nios2-linux/linux-2.6/drivers/char/altera_pio_button.c:113: error: (Each undeclared identifier is reported only once

/media/disk/nios2-linux/linux-2.6/drivers/char/altera_pio_button.c:113: error: for each function it appears in.)

can somebody tell me please how to fix this error , and is there a way to access or display data on the 7 segment on the de2 board .

Thanks all