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Date:   Mon, 4 Jan 2021 13:30:05 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Andrew Lunn <andrew@lunn.ch>,
        Charles Keepax <ckeepax@opensource.cirrus.com>
Cc:     nicolas.ferre@microchip.com, claudiu.beznea@microchip.com,
        davem@davemloft.net, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net v3] net: macb: Correct usage of MACB_CAPS_CLK_HW_CHG
 flag
Message-ID: <20210104133005.22c5488d@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <X/MjyvgHJZrhYQw3@lunn.ch>
References: <20210104103802.13091-1-ckeepax@opensource.cirrus.com>
        <X/MjyvgHJZrhYQw3@lunn.ch>
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Precedence: bulk

On Mon, 4 Jan 2021 15:18:50 +0100 Andrew Lunn wrote:
> On Mon, Jan 04, 2021 at 10:38:02AM +0000, Charles Keepax wrote:
> > A new flag MACB_CAPS_CLK_HW_CHG was added and all callers of
> > macb_set_tx_clk were gated on the presence of this flag.
> > 
> > -   if (!clk)
> > + if (!bp->tx_clk || !(bp->caps & MACB_CAPS_CLK_HW_CHG))
> > 
> > However the flag was not added to anything other than the new
> > sama7g5_gem, turning that function call into a no op for all other
> > systems. This breaks the networking on Zynq.
> > 
> > The commit message adding this states: a new capability so that
> > macb_set_tx_clock() to not be called for IPs having this
> > capability
> > 
> > This strongly implies that present of the flag was intended to skip
> > the function not absence of the flag. Update the if statement to
> > this effect, which repairs the existing users.
> > 
> > Fixes: daafa1d33cc9 ("net: macb: add capability to not set the clock rate")
> > Suggested-by: Andrew Lunn <andrew@lunn.ch>
> > Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>  
> 
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>

Applied, thanks!