diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 546d05f4358a7c452ee80366b3ae782e685fd7ef..b2bbe8659beda5ad8182b5f4ff7bbefeda970459 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -81,6 +81,7 @@ config STI_MBOX
 config MAILBOX_TEST
 	tristate "Mailbox Test Client"
 	depends on OF
+	depends on HAS_IOMEM
 	help
 	  Test client to help with testing new Controller driver
 	  implementations.
diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
index 45d85aea9955404d0c4567f33863e0e3f500674f..8f779a1ec99c4b248c9721fceef19b579432539b 100644
--- a/drivers/mailbox/pcc.c
+++ b/drivers/mailbox/pcc.c
@@ -81,16 +81,10 @@ static struct mbox_controller pcc_mbox_ctrl = {};
  */
 static struct mbox_chan *get_pcc_channel(int id)
 {
-	struct mbox_chan *pcc_chan;
-
 	if (id < 0 || id > pcc_mbox_ctrl.num_chans)
 		return ERR_PTR(-ENOENT);
 
-	pcc_chan = (struct mbox_chan *)
-		(unsigned long) pcc_mbox_channels +
-		(id * sizeof(*pcc_chan));
-
-	return pcc_chan;
+	return &pcc_mbox_channels[id];
 }
 
 /**