Re: [PATCH v5 1/4] usb: port: track the disabled state

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

On Fri, Mar 20, 2026 at 11:16:43PM +0100, Marco Felsch wrote:
> On 26-03-11, Greg Kroah-Hartman wrote:
> > On Mon, Feb 23, 2026 at 12:27:34PM +0100, Marco Felsch wrote:
> > > The disable state isn't tracked at the moment, instead the state is
> > > directly passed to the hub driver. Change this behavior to only trigger
> > > the hub if a state change happened. Exit early in case of no state
> > > changes but don't return an error.
> > > 
> > > Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
> 
> ...
> 
> > >  #define to_usb_port(_dev) \
> > > diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
> > > index 44e38f922bc553adee64b35c536dfd4154a42d8a..86e9d6d0c0f505782569565fde8e4a46b06b8b4d 100644
> > > --- a/drivers/usb/core/port.c
> > > +++ b/drivers/usb/core/port.c
> > > @@ -117,6 +117,10 @@ static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
> > >  	if (rc)
> > >  		return rc;
> > >  
> > > +	/* Early quit if no change was detected */
> > > +	if (port_dev->disabled == disabled)
> > > +		return count;
> > > +
> > 
> > This will change behavior where someone tells the port to be enabled
> > again, when it already is.  Is that ok?
> 
> That's the whole purpose of this patch. Can you please elaborate why
> someone wants to enable or disbale a port more than once in a row?

I have given up trying to understand why users do what users do :)