diff --git a/arch/arm/mach-omap1/board-ams-delta.c b/arch/arm/mach-omap1/board-ams-delta.c
index 6613a6ff5dbc..6cbc69c92913 100644
--- a/arch/arm/mach-omap1/board-ams-delta.c
+++ b/arch/arm/mach-omap1/board-ams-delta.c
@@ -510,6 +510,7 @@ static void __init ams_delta_init(void)
 static void modem_pm(struct uart_port *port, unsigned int state, unsigned old)
 {
 	struct modem_private_data *priv = port->private_data;
+	int ret;
 
 	if (IS_ERR(priv->regulator))
 		return;
@@ -518,9 +519,16 @@ static void modem_pm(struct uart_port *port, unsigned int state, unsigned old)
 		return;
 
 	if (state == 0)
-		regulator_enable(priv->regulator);
+		ret = regulator_enable(priv->regulator);
 	else if (old == 0)
-		regulator_disable(priv->regulator);
+		ret = regulator_disable(priv->regulator);
+	else
+		ret = 0;
+
+	if (ret)
+		dev_warn(port->dev,
+			 "ams_delta modem_pm: failed to %sable regulator: %d\n",
+			 state ? "dis" : "en", ret);
 }
 
 static struct plat_serial8250_port ams_delta_modem_ports[] = {