From: Thomas Renninger <trenn@xxxxxxx> 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@xxxxxxx> Acked-by: Bjorn Helgaas <bjorn.helgaas@xxxxxx> Signed-off-by: Len Brown <len.brown@xxxxxxxxx> --- drivers/acpi/scan.c | 24 +++++++++++++++++++----- drivers/pci/hotplug/acpiphp_glue.c | 6 ------ 2 files changed, 19 insertions(+), 11 deletions(-) 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 @@ static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops, 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 @@ 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); diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index 8e952fd..cb2fd01 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -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: -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
