Re: [PATCH v2] usb: core: Add ACPI support for USB interface devices

["Rafael J. Wysocki" <rafael@kernel.org>]

On Tue, Mar 24, 2020 at 11:09 AM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> Currently on ACPI-enabled systems the USB interface device has no link to
> the actual firmware node and thus drivers may not parse additional information
> given in the table. The new feature, proposed here, allows to pass properties
> or other information to the drivers.
>
> The ACPI companion of the device has to be set for USB interface devices
> to achieve above. Use ACPI_COMPANION_SET macro to set this.
>
> Note, OF already does link of_node and this is the same for ACPI case.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
> v2: rewrite commit message to emphasize that it is a new feature (Greg)
>  drivers/usb/core/message.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
> index 5adf489428aa..d5f834f16993 100644
> --- a/drivers/usb/core/message.c
> +++ b/drivers/usb/core/message.c
> @@ -5,6 +5,7 @@
>   * Released under the GPLv2 only.
>   */
>
> +#include <linux/acpi.h>
>  #include <linux/pci.h> /* for scatterlist macros */
>  #include <linux/usb.h>
>  #include <linux/module.h>
> @@ -1941,6 +1942,7 @@ int usb_set_configuration(struct usb_device *dev, int configuration)
>                         intf->dev.of_node = usb_of_get_interface_node(dev,
>                                         configuration, ifnum);
>                 }
> +               ACPI_COMPANION_SET(&intf->dev, ACPI_COMPANION(&dev->dev));
>                 intf->dev.driver = NULL;
>                 intf->dev.bus = &usb_bus_type;
>                 intf->dev.type = &usb_if_device_type;
> --
> 2.25.1
>