[PATCH v1 05/16] USB: ACPI: Use acpi_find_child_by_adr()

From: Rafael J. Wysocki
Date: Thu Jun 09 2022 - 10:22:12 EST


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.

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>
---
drivers/usb/core/usb-acpi.c | 9 +--------
1 file changed, 1 insertion(+), 8 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
@@ -127,17 +127,10 @@ out:
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);
+ return acpi_find_child_by_adr(parent, raw);
}

static struct acpi_device *