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Date:   Sun, 26 Jun 2022 10:58:24 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Lukas Wunner <lukas@wunner.de>
Cc:     Oleksij Rempel <o.rempel@pengutronix.de>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, kernel@pengutronix.de,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH net-next v1 1/1] net: phy: ax88772a: fix lost pause
 advertisement configuration
Message-ID: <YrgfsPq4lrYnSStk@lunn.ch>
References: <20220624075558.3141464-1-o.rempel@pengutronix.de>
 <20220625071731.GA3462@wunner.de>
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On Sat, Jun 25, 2022 at 09:17:31AM +0200, Lukas Wunner wrote:
> On Fri, Jun 24, 2022 at 09:55:58AM +0200, Oleksij Rempel wrote:
> > In case of asix_ax88772a_link_change_notify() workaround, we run soft
> > reset which will automatically clear MII_ADVERTISE configuration. The
> > PHYlib framework do not know about changed configuration state of the
> > PHY, so we need to save and restore all needed configuration registers.
> [...]
> >  static void asix_ax88772a_link_change_notify(struct phy_device *phydev)
> >  {
> >  	/* Reset PHY, otherwise MII_LPA will provide outdated information.
> >  	 * This issue is reproducible only with some link partner PHYs
> >  	 */
> > -	if (phydev->state == PHY_NOLINK && phydev->drv->soft_reset)
> > +	if (phydev->state == PHY_NOLINK && phydev->drv->soft_reset) {
> > +		struct asix_context context;
> > +
> > +		asix_context_save(phydev, &context);
> > +
> >  		phydev->drv->soft_reset(phydev);
> > +
> > +		asix_context_restore(phydev, &context);
> > +	}
> >  }
> 
> Hm, how about just calling phy_init_hw()?  That will perform a
> ->soft_reset() and also restore the configuration, including
> interrupts (which the above does not, but I guess that's
> irrelevant as long as the driver uses polling).
> 
> Does phy_init_hw() do too much or too little compared to the above
> and is hence not a viable solution?


at803x.c has:

        /* After changing the smart speed settings, we need to perform a
         * software reset, use phy_init_hw() to make sure we set the
         * reapply any values which might got lost during software reset.
         */
        if (ret == 1)
                ret = phy_init_hw(phydev);

	Andrew