netdev - Re: [PATCH net-next 1/4] net: phylib: add getting reference clock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <e39a20a2-c01e-343a-15e8-e917e9451dbe@gmail.com>
Date:   Fri, 24 Mar 2023 12:10:29 -0700
From:   Florian Fainelli <f.fainelli@...il.com>
To:     Heiner Kallweit <hkallweit1@...il.com>,
        Andrew Lunn <andrew@...n.ch>,
        Russell King - ARM Linux <linux@...linux.org.uk>,
        Jakub Kicinski <kuba@...nel.org>,
        David Miller <davem@...emloft.net>,
        Paolo Abeni <pabeni@...hat.com>,
        Eric Dumazet <edumazet@...gle.com>,
        Florian Fainelli <f.fainelli@...il.com>,
        Broadcom internal kernel review list 
        <bcm-kernel-feedback-list@...adcom.com>
Cc:     "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next 1/4] net: phylib: add getting reference clock

On 3/24/23 11:03, Heiner Kallweit wrote:
> Few PHY drivers (smsc, bcm7xxx, micrel) get and enable the (R)MII
> reference clock in their probe() callback. Move this common
> functionality to phylib, this allows to remove it from the drivers
> in a follow-up.
> 
> Note that we now enable the reference clock before deasserting the
> PHY reset signal. Maybe this even allows us to get rid of
> phy_reset_after_clk_enable().
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@...il.com>
> ---
>   drivers/net/phy/phy_device.c | 6 ++++++
>   include/linux/phy.h          | 5 +++++
>   2 files changed, 11 insertions(+)
> 
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index c0760cbf5..6668487e2 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -3096,6 +3096,12 @@ static int phy_probe(struct device *dev)
>   	if (phydrv->flags & PHY_IS_INTERNAL)
>   		phydev->is_internal = true;
>   
> +	phydev->refclk = devm_clk_get_optional_enabled(dev, NULL);
> +	if (IS_ERR(phydev->refclk)) {
> +		err = PTR_ERR(phydev->refclk);
> +		goto out;
> +	}

My comment in patch 2 should have been there, I would add a flag that 
the PHY driver can set that tells the core that it is OK to fetch the 
clock. In the case of bcm7xxx.c is it not the reference clock, so while 
we can use phydev->refclk for the same purpose, it could be a tad confusing.
-- 
Florian