1 files changed, 12 insertions, 0 deletions

diff --git a/include/linux/i2c-vid.h b/include/linux/i2c-vid.h
index 974835e3530f..41d0635e0ba9 100644
--- a/include/linux/i2c-vid.h
+++ b/include/linux/i2c-vid.h
@@ -97,3 +97,15 @@ static inline int vid_from_reg(int val, int vrm)
                                      2050 - (val) * 50);
         }
 }
+
+static inline int vid_to_reg(int val, int vrm)
+{
+        switch (vrm) {
+        case 91:                /* VRM 9.1 */
+        case 90:                /* VRM 9.0 */
+                return ((val >= 1100) && (val <= 1850) ?
+                        ((18499 - val * 10) / 25 + 5) / 10 : -1);
+        default:
+                return -1;
+        }
+}