diff --git a/docs/change-log.md b/docs/change-log.md
index 3ae5fab..73d7e7a 100644
--- a/docs/change-log.md
+++ b/docs/change-log.md
@@ -49,6 +49,9 @@
     physically powered up to prevent a spurious wake up from a subsequent cpu
     off state.
 
+*   Definitions of some constants related to the PSCI api calls AFFINITY_INFO
+    and CPU_SUSPEND have been corrected.
+
 ARM Trusted Firmware - version 0.2
 ==================================
 
diff --git a/include/psci.h b/include/psci.h
index e5eb997..70322c4 100644
--- a/include/psci.h
+++ b/include/psci.h
@@ -60,9 +60,9 @@
 /*******************************************************************************
  * PSCI CPU_SUSPEND 'power_state' parameter specific defines
  ******************************************************************************/
-#define PSTATE_ID_SHIFT		15
+#define PSTATE_ID_SHIFT		0
 #define PSTATE_TYPE_SHIFT	16
-#define PSTATE_AFF_LVL_SHIFT	25
+#define PSTATE_AFF_LVL_SHIFT	24
 
 #define PSTATE_ID_MASK		0xffff
 #define PSTATE_TYPE_MASK	0x1
@@ -107,10 +107,10 @@
 
 #define PSCI_AFF_ABSENT		0x0
 #define PSCI_AFF_PRESENT	0x1
-#define PSCI_STATE_OFF		0x0
-#define PSCI_STATE_ON_PENDING	0x1
-#define PSCI_STATE_SUSPEND	0x2
-#define PSCI_STATE_ON		0x3
+#define PSCI_STATE_ON		0x0
+#define PSCI_STATE_OFF		0x1
+#define PSCI_STATE_ON_PENDING	0x2
+#define PSCI_STATE_SUSPEND	0x3
 
 /* Number of affinity instances whose state this psci imp. can track */
 #define PSCI_NUM_AFFS		32ull