diff --git a/sys/sys/ata.h b/sys/sys/ata.h
index 863f0e8d61ab..272b46a553d5 100644
--- a/sys/sys/ata.h
+++ b/sys/sys/ata.h
@@ -399,6 +399,7 @@ struct ata_params {
 #define ATA_IDLE_CMD                    0xe3    /* idle */
 #define ATA_READ_BUFFER                 0xe4    /* read buffer */
 #define ATA_READ_PM                     0xe4    /* read portmultiplier */
+#define ATA_CHECK_POWER_MODE            0xe5    /* device power mode */
 #define ATA_SLEEP                       0xe6    /* sleep */
 #define ATA_FLUSHCACHE                  0xe7    /* flush cache to disk */
 #define ATA_WRITE_PM                    0xe8    /* write portmultiplier */