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Date:   Thu, 8 Aug 2019 22:34:15 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Heiner Kallweit <hkallweit1@gmail.com>
Cc:     Yonglong Liu <liuyonglong@huawei.com>, davem@davemloft.net,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linuxarm@huawei.com, salil.mehta@huawei.com,
        yisen.zhuang@huawei.com, shiju.jose@huawei.com
Subject: Re: [PATCH net] net: phy: rtl8211f: do a double read to get real
 time link status
Message-ID: <20190808203415.GO27917@lunn.ch>
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On Thu, Aug 08, 2019 at 10:01:39PM +0200, Heiner Kallweit wrote:
> On 08.08.2019 21:40, Andrew Lunn wrote:
> >> @@ -568,6 +568,11 @@ int phy_start_aneg(struct phy_device *phydev)
> >>  	if (err < 0)
> >>  		goto out_unlock;
> >>  
> >> +	/* The PHY may not yet have cleared aneg-completed and link-up bit
> >> +	 * w/o this delay when the following read is done.
> >> +	 */
> >> +	usleep_range(1000, 2000);
> >> +
> > 
> > Hi Heiner
> > 
> > Does 802.3 C22 say anything about this?
> > 
> C22 says:
> "The Auto-Negotiation process shall be restarted by setting bit 0.9 to a logic one. This bit is self-
> clearing, and a PHY shall return a value of one in bit 0.9 until the Auto-Negotiation process has been
> initiated."
> 
> Maybe we should read bit 0.9 in genphy_update_link() after having read BMSR and report
> aneg-complete and link-up as false (no matter of their current value) if 0.9 is set.

Yes. That sounds sensible.

     Andrew