ACPI: acpi_bus_{scan,bus,add}: return -ENODEV if no device was found
Callers (acpi_memhotplug.c, dock.c and others) check for the return
value of acpi_bus_add() and assume a valid device was returned in
case zero was returned.
Thus return -ENODEV if no device was found in acpi_bus_scan and
propagate this through acpi_bus_add and acpi_bus_start.
Also remove a confusing comment in acpiphp_glue.c, acpi_bus_scan
will and cannot invoke if acpi_bus_add returns no valid device.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 8044583..3e00967 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1336,9 +1336,25 @@
if (child)
*child = device;
- return 0;
+
+ if (device)
+ return 0;
+ else
+ return -ENODEV;
}
+/*
+ * acpi_bus_add and acpi_bus_start
+ *
+ * scan a given ACPI tree and (probably recently hot-plugged)
+ * create and add or starts found devices.
+ *
+ * If no devices were found -ENODEV is returned which does not
+ * mean that this is a real error, there just have been no suitable
+ * ACPI objects in the table trunk from which the kernel could create
+ * a device and add/start an appropriate driver.
+ */
+
int
acpi_bus_add(struct acpi_device **child,
struct acpi_device *parent, acpi_handle handle, int type)
@@ -1348,8 +1364,7 @@
memset(&ops, 0, sizeof(ops));
ops.acpi_op_add = 1;
- acpi_bus_scan(handle, &ops, child);
- return 0;
+ return acpi_bus_scan(handle, &ops, child);
}
EXPORT_SYMBOL(acpi_bus_add);
@@ -1363,8 +1378,7 @@
memset(&ops, 0, sizeof(ops));
ops.acpi_op_start = 1;
- acpi_bus_scan(device->handle, &ops, NULL);
- return 0;
+ return acpi_bus_scan(device->handle, &ops, NULL);
}
EXPORT_SYMBOL(acpi_bus_start);