[PATCH v2 1/3] units: Add SI metric prefix definitions

[Andy Shevchenko]

Sometimes it's useful to have well-defined SI metric prefix to be used
to self-describe the formulas or equations.

List most popular ones in the units.h.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
v2: no changes
 include/linux/units.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/include/linux/units.h b/include/linux/units.h
index dcc30a53fa93..7366fcd45ec2 100644
--- a/include/linux/units.h
+++ b/include/linux/units.h
@@ -4,6 +4,22 @@
 
 #include <linux/math.h>
 
+/* Metric prefixes in accordance with Système international (d'unités) */
+#define PETA	1000000000000000LL
+#define TERA	1000000000000LL
+#define GIGA	1000000000L
+#define MEGA	1000000L
+#define KILO	1000L
+#define HECTO	100L
+#define DECA	10L
+#define DECI	10L
+#define CENTI	100L
+#define MILLI	1000L
+#define MICRO	1000000L
+#define NANO	1000000000L
+#define PICO	1000000000000LL
+#define FEMTO	1000000000000000LL
+
 #define MILLIWATT_PER_WATT	1000L
 #define MICROWATT_PER_MILLIWATT	1000L
 #define MICROWATT_PER_WATT	1000000L
-- 
2.30.2