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>
This commit is contained in:
Thomas Renninger 2010-01-29 17:48:52 +01:00 committed by Len Brown
parent d2f6650a95
commit 7779688fc3
2 changed files with 19 additions and 11 deletions

View File

@ -1336,9 +1336,25 @@ static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
if (child)
*child = device;
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 @@ acpi_bus_add(struct acpi_device **child,
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 @@ int acpi_bus_start(struct acpi_device *device)
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);

View File

@ -720,12 +720,6 @@ static int acpiphp_bus_add(struct acpiphp_func *func)
-ret_val);
goto acpiphp_bus_add_out;
}
/*
* try to start anyway. We could have failed to add
* simply because this bus had previously been added
* on another add. Don't bother with the return value
* we just keep going.
*/
ret_val = acpi_bus_start(device);
acpiphp_bus_add_out: