Sample values in comedi are generally represented as unsigned values. Change the interrupt data transfer functions in the "pcl818" module to use unsigned types for consistency. Also remove the `short *ai_data` member of `struct pcl818_private` as it is only assigned to and otherwise unused. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>