ACPICA: _OSI Support: handle any errors from acpi_os_acquire_mutex()

Check for any errors. Handles possible timeout case if
ACPI_WAIT_FOREVER is changed to be less than "forever".
Jung-uk Kim.

Signed-off-by: Jung-uk Kim <jkim@FreeBSD.org>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/acpica/utxface.c b/drivers/acpi/acpica/utxface.c
index 48efb44..6505774 100644
--- a/drivers/acpi/acpica/utxface.c
+++ b/drivers/acpi/acpica/utxface.c
@@ -287,7 +287,10 @@
 		return (AE_BAD_PARAMETER);
 	}
 
-	(void)acpi_os_acquire_mutex(acpi_gbl_osi_mutex, ACPI_WAIT_FOREVER);
+	status = acpi_os_acquire_mutex(acpi_gbl_osi_mutex, ACPI_WAIT_FOREVER);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
 
 	/* Check if the interface name is already in the global list */
 
@@ -336,7 +339,10 @@
 		return (AE_BAD_PARAMETER);
 	}
 
-	(void)acpi_os_acquire_mutex(acpi_gbl_osi_mutex, ACPI_WAIT_FOREVER);
+	status = acpi_os_acquire_mutex(acpi_gbl_osi_mutex, ACPI_WAIT_FOREVER);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
 
 	status = acpi_ut_remove_interface(interface_name);
 
@@ -362,9 +368,12 @@
  ****************************************************************************/
 acpi_status acpi_install_interface_handler(acpi_interface_handler handler)
 {
-	acpi_status status = AE_OK;
+	acpi_status status;
 
-	(void)acpi_os_acquire_mutex(acpi_gbl_osi_mutex, ACPI_WAIT_FOREVER);
+	status = acpi_os_acquire_mutex(acpi_gbl_osi_mutex, ACPI_WAIT_FOREVER);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
 
 	if (handler && acpi_gbl_interface_handler) {
 		status = AE_ALREADY_EXISTS;