Re: [PATCH v4 05/14] usb: hub: Associate port@ fwnode with USB port device

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, Jul 09, 2026 at 05:57:10PM +0800, Chen-Yu Tsai wrote:
> When a USB hub port is connected to a connector in a firmware node
> graph, the port itself has a node in the graph.
> 
> Associate the port's firmware node with the USB port's device,
> usb_port::dev. This is used in later changes for the M.2 slot power
> sequencing provider to match against the requesting port.
> 
> To avoid potential conflicts with ACPI firmware nodes and then causing
> power management issues, only assign the firmware node if the hub's
> firmware node is not an ACPI firmware node.
> 
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> ---
> Changes since v3:
> - Added missing fwnode_handle_put()
> 
> Changes since v2:
> - Skip assignment if hub firmware node is ACPI node
> ---
>  drivers/usb/core/port.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
> index b1364f0c384c..e8fb2acd77be 100644
> --- a/drivers/usb/core/port.c
> +++ b/drivers/usb/core/port.c
> @@ -7,6 +7,7 @@
>   * Author: Lan Tianyu <tianyu.lan@intel.com>
>   */
>  
> +#include <linux/acpi.h>
>  #include <linux/kstrtox.h>
>  #include <linux/slab.h>
>  #include <linux/string_choices.h>
> @@ -358,6 +359,11 @@ static void usb_port_device_release(struct device *dev)
>  {
>  	struct usb_port *port_dev = to_usb_port(dev);
>  
> +	/*
> +	 * At this point ACPI nodes and swnodes have been removed by
> +	 * device_platform_notify_remove() in device_del().
> +	 */
> +	fwnode_handle_put(dev_fwnode(dev));
>  	kfree(port_dev->req);
>  	kfree(port_dev);
>  }
> @@ -780,6 +786,13 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1)
>  	port_dev->dev.driver = &usb_port_driver;
>  	dev_set_name(&port_dev->dev, "%s-port%d", dev_name(&hub->hdev->dev),
>  			port1);
> +	/*
> +	 * ACPI FW nodes are associated later when device_register() happens.
> +	 * Skip assigning one here to avoid potential conflicts.
> +	 */
> +	if (!is_acpi_node(dev_fwnode(&hdev->dev)))
> +		device_set_node(&port_dev->dev,
> +				fwnode_graph_get_port_by_id(dev_fwnode(&hdev->dev), port1));
>  	mutex_init(&port_dev->status_lock);
>  	retval = device_register(&port_dev->dev);
>  	if (retval) {
> @@ -852,6 +865,7 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1)
>  
>  void usb_hub_remove_port_device(struct usb_hub *hub, int port1)
>  {
> +	struct usb_device *hdev = hub->hdev;
>  	struct usb_port *port_dev = hub->ports[port1 - 1];
>  	struct usb_port *peer;

Is this last variable addition not needed here?  It's not used.

thanks,

greg k-h