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

Heikki Krogerus
2022-06-10T06:47:45Z

On Thu, Jun 09, 2022 at 03:56:42PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> 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@intel.com>
> ---
> 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 *

I think usb_acpi_find_port() can also be dropped now.

thanks,

--
heikki