Re: [RFC PATCH v2 19/19] hw/usb: Inline usb_bus_from_device()

[Thomas Huth <thuth@redhat.com>]

On 13/02/2023 08.08, Philippe Mathieu-Daudé wrote:
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
> RFC Other devices don't use such helper. Maybe it should
>      be the other way around, introduce more bus_from_device()
>      helpers?
> ---
>   hw/usb/bus.c        | 10 +++++-----
>   hw/usb/core.c       |  6 +++---
>   hw/usb/dev-hub.c    |  4 ++--
>   hw/usb/dev-serial.c | 10 +++++-----
>   hw/usb/hcd-xhci.c   |  2 +-
>   include/hw/usb.h    |  5 -----
>   6 files changed, 16 insertions(+), 21 deletions(-)
> 
> diff --git a/hw/usb/bus.c b/hw/usb/bus.c
> index d7c3c71435..4a1b67761c 100644
> --- a/hw/usb/bus.c
> +++ b/hw/usb/bus.c
> @@ -427,7 +427,7 @@ void usb_unregister_port(USBBus *bus, USBPort *port)
>   
>   void usb_claim_port(USBDevice *dev, Error **errp)
>   {
> -    USBBus *bus = usb_bus_from_device(dev);
> +    USBBus *bus = USB_BUS(qdev_get_parent_bus(DEVICE(dev)));

You're certainly missing a proper justification in the patch description 
here. The "other devices don't use such a helper" does not sound like a real 
justification to me, since the code lines rather get longer this way. Thus 
this rather looks like unnecessary code churn to me --> rather drop the patch?

  Thomas