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Date:   Wed, 9 Jun 2021 14:17:44 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Cc:     Joakim Zhang <qiangqing.zhang@nxp.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "kuba@kernel.org" <kuba@kernel.org>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "hkallweit1@gmail.com" <hkallweit1@gmail.com>,
        "linux@armlinux.org.uk" <linux@armlinux.org.uk>,
        "f.fainelli@gmail.com" <f.fainelli@gmail.com>,
        dl-linux-imx <linux-imx@nxp.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH V3 net-next 3/4] net: phy: realtek: add dt property to
 enable ALDPS mode
Message-ID: <YMCxaAOs2UYRHEnF@lunn.ch>
References: <20210608031535.3651-1-qiangqing.zhang@nxp.com>
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 <20210608175104.7ce18d1d@xhacker.debian>
 <DB8PR04MB6795D312FDECF820164B0DE6E6379@DB8PR04MB6795.eurprd04.prod.outlook.com>
 <20210609095633.1bce2c22@xhacker.debian>
 <DB8PR04MB67955F0424EAEBF362D34B30E6369@DB8PR04MB6795.eurprd04.prod.outlook.com>
 <20210609110428.5a136b03@xhacker.debian>
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> Aha, I see you want to keep the ALDPS bits(maybe configured by prelinux env) untouched.
> If ALDPS has been enabled by prelinux env, even there's no "realtek,aldps-enable"
> in DT, the ALDPS may be keep enabled in linux. Thus the ALDPS behavior rely on
> the prelinux env. I'm not sure whether this is correct or not.
> 
> IMHO, the "realtek,aldps-enable" is a "yes" or "no" bool. If it's set, ALDPS
> will be enabled in linux; If it's no, ALDPS will be disabled in linux. We
> should not rely on prelinux env.

If you look at V1 of this patch, you will see i commented that maybe
it needs to be a tristate, not a boolean. Disable it, enable it, leave
it as is. If we do need the third state, we can add it latter.

There is something to be said for not relying on the bootloader. But
the hardware default appears to be ALDPS enabled. So this case seems
reasonably safe.

	   Andrew