First stab at IOCTL driven offset handling (in PA) for all airspeed sensors. Untested

src/drivers/drv_airspeed.h

@@ -57,5 +57,14 @@
 #define _AIRSPEEDIOCBASE		(0x7700)
 #define __AIRSPEEDIOC(_n)		(_IOC(_AIRSPEEDIOCBASE, _n))
 
+#define AIRSPEEDIOCSSCALE		__AIRSPEEDIOC(0)
+#define AIRSPEEDIOCGSCALE		__AIRSPEEDIOC(1)
+
+
+/** airspeed scaling factors; out = (in * Vscale) + offset */
+struct airspeed_scale {
+	float	offset_pa;
+	float	scale;
+};
 
 #endif /* _DRV_AIRSPEED_H */