From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Instead of walking the list of children of an ACPI device directly in order to find the child matching a given bus address, use acpi_find_child_by_adr() for this purpose. Also notice that if acpi_find_child_by_adr() doesn't find a matching child, acpi_find_child_device() will not find it too, so directly replace usb_acpi_find_port() in usb_acpi_get_companion_for_port() with acpi_find_child_by_adr() and drop it entirely. Apart from simplifying the code, this will help to eliminate the children list head from struct acpi_device as it is redundant and it is used in questionable ways in some places (in particular, locking is needed for walking the list pointed to it safely, but it is often missing). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- v1 -> v2: * Drop usb_acpi_find_port() (Heikki, Andy). * Change the subject accordingly. --- drivers/usb/core/usb-acpi.c | 18 +----------------- 1 file changed, 1 insertion(+), 17 deletions(-) Index: linux-pm/drivers/usb/core/usb-acpi.c =================================================================== --- linux-pm.orig/drivers/usb/core/usb-acpi.c +++ linux-pm/drivers/usb/core/usb-acpi.c @@ -124,22 +124,6 @@ out: */ #define USB_ACPI_LOCATION_VALID (1 << 31) -static struct acpi_device *usb_acpi_find_port(struct acpi_device *parent, - int raw) -{ - struct acpi_device *adev; - - if (!parent) - return NULL; - - list_for_each_entry(adev, &parent->children, node) { - if (acpi_device_adr(adev) == raw) - return adev; - } - - return acpi_find_child_device(parent, raw, false); -} - static struct acpi_device * usb_acpi_get_companion_for_port(struct usb_port *port_dev) { @@ -170,7 +154,7 @@ usb_acpi_get_companion_for_port(struct u port1 = port_dev->portnum; } - return usb_acpi_find_port(adev, port1); + return acpi_find_child_by_adr(adev, port1); } static struct acpi_device *