ACPI: gracefully print null trip-point device

if acpi_bus_get_device() returns NULL, print nothing
instead of "<NUL" in /proc/acpi/thermal_zone/*/trip_points

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 194ecfe8b360..88a6fc7fd271 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -828,6 +828,8 @@ static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset)
 {
         struct acpi_thermal *tz = seq->private;
         struct acpi_device *device;
+        acpi_status status;
+
         int i = 0;
         int j = 0;
 
@@ -850,8 +852,10 @@ static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset)
                            tz->trips.passive.tc1, tz->trips.passive.tc2,
                            tz->trips.passive.tsp);
                 for (j = 0; j < tz->trips.passive.devices.count; j++) {
-                        acpi_bus_get_device(tz->trips.passive.devices.handles[j], &device);
-                        seq_printf(seq, "%4.4s ", acpi_device_bid(device));
+                        status = acpi_bus_get_device(tz->trips.passive.devices.
+                                                     handles[j], &device);
+                        seq_printf(seq, "%4.4s ", status ? "" :
+                                   acpi_device_bid(device));
                 }
                 seq_puts(seq, "\n");
         }
@@ -863,8 +867,11 @@ static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset)
                            i,
                            KELVIN_TO_CELSIUS(tz->trips.active[i].temperature));
                 for (j = 0; j < tz->trips.active[i].devices.count; j++){
-                        acpi_bus_get_device(tz->trips.active[i].devices.handles[j], &device);
-                        seq_printf(seq, "%4.4s ", acpi_device_bid(device));
+                        status = acpi_bus_get_device(tz->trips.active[i].
+                                                     devices.handles[j],
+                                                     &device);
+                        seq_printf(seq, "%4.4s ", status ? "" :
+                                   acpi_device_bid(device));
                 }
                 seq_puts(seq, "\n");
         }