netdev - Re: [PATCH net-next 3/4] net: phy: realteck: add dt property to disable ALDPS mode

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Date:   Tue, 1 Jun 2021 12:52:19 +0100
From:   "Russell King (Oracle)" <linux@...linux.org.uk>
To:     Joakim Zhang <qiangqing.zhang@....com>
Cc:     davem@...emloft.net, kuba@...nel.org, robh+dt@...nel.org,
        andrew@...n.ch, hkallweit1@...il.com, f.fainelli@...il.com,
        linux-imx@....com, netdev@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next 3/4] net: phy: realteck: add dt property to
 disable ALDPS mode

On Tue, Jun 01, 2021 at 05:04:07PM +0800, Joakim Zhang wrote:
> @@ -325,8 +329,10 @@ static int rtl8211f_config_init(struct phy_device *phydev)
>  	u16 val;
>  	int ret;
>  
> -	val = RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_XTAL_OFF;
> -	phy_modify_paged_changed(phydev, 0xa43, RTL8211F_PHYCR1, val, val);
> +	if (!(priv->quirks & RTL821X_ALDPS_DISABLE_FEATURE)) {
> +		val = RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_XTAL_OFF;
> +		phy_modify_paged_changed(phydev, 0xa43, RTL8211F_PHYCR1, val, val);
> +	}

Similar questions as with the previous patch, but also... this doesn't
actually disable the feature if it was previously turned on. E.g. a
kexec() from a current kernel that has set these features into a
subsequent kernel that the DT requests the feature to be disabled. Or
a boot loader that has enabled this feature.

If DT specifies that this feature is disabled, shouldn't this code be
disabling it explicitly?

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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