Misc: phantom, improved data passing

This new version guarantees amb_bit switch in small enough intervals, so that
the device won't stop working in the middle of a movement anymore.  However it
preserves old (openhaptics) functionality.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/phantom.h b/include/linux/phantom.h
index d3ebbfa..96f4048 100644
--- a/include/linux/phantom.h
+++ b/include/linux/phantom.h
@@ -30,7 +30,11 @@
 #define PHN_SET_REG		_IOW (PH_IOC_MAGIC, 1, struct phm_reg *)
 #define PHN_GET_REGS		_IOWR(PH_IOC_MAGIC, 2, struct phm_regs *)
 #define PHN_SET_REGS		_IOW (PH_IOC_MAGIC, 3, struct phm_regs *)
-#define PH_IOC_MAXNR		3
+/* this ioctl tells the driver, that the caller is not OpenHaptics and might
+ * use improved registers update (no more phantom switchoffs when using
+ * libphantom) */
+#define PHN_NOT_OH		_IO  (PH_IOC_MAGIC, 4)
+#define PH_IOC_MAXNR		4
 
 #define PHN_CONTROL		0x6     /* control byte in iaddr space */
 #define PHN_CTL_AMP		0x1     /*   switch after torques change */