diff --git a/ChangeLog b/ChangeLog
index 0d0219d9e..492c45b72 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2011-12-12  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/disk/ahci.c (grub_ahci_pciinit): Fix compat condition.
+
 2011-11-30  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	Add missing const qualifiers.
diff --git a/grub-core/disk/ahci.c b/grub-core/disk/ahci.c
index 38c4d5e2d..00fc889a7 100644
--- a/grub-core/disk/ahci.c
+++ b/grub-core/disk/ahci.c
@@ -305,7 +305,7 @@ grub_ahci_pciinit (grub_pci_device_t dev,
   else
     grub_dprintf ("ahci", "AHCI is already in OS mode\n");
 
-  if (~(hba->global_control & GRUB_AHCI_HBA_GLOBAL_CONTROL_AHCI_EN))
+  if (!(hba->global_control & GRUB_AHCI_HBA_GLOBAL_CONTROL_AHCI_EN))
     grub_dprintf ("ahci", "AHCI is in compat mode. Switching\n");
   else
     grub_dprintf ("ahci", "AHCI is in AHCI mode.\n");