Re: [PATCH] ARM: dts: add phy-reset property for rk3066a-rayeager emac

From: Chris Zhong <zyw@rock-chips.com>
To: Florian Fainelli <f.fainelli@gmail.com>,
	Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>,
	Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>,
	Roger Quadros <rogerq@ti.com>,
	andrew@lunn.ch
Cc: Mark Rutland <mark.rutland@arm.com>,
	devicetree@vger.kernel.org, heiko@sntech.de,
	netdev@vger.kernel.org, Russell King <linux@armlinux.org.uk>,
	linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org,
	Rob Herring <robh+dt@kernel.org>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] ARM: dts: add phy-reset property for rk3066a-rayeager emac
Date: Wed, 8 Nov 2017 17:49:55 +0800	[thread overview]
Message-ID: <464f7b9f-1c07-286e-1b7f-bdef0332b4c9@rock-chips.com> (raw)
In-Reply-To: <ac15ef59-3b5e-1752-09db-0a773615f44c@gmail.com>

Hi Florian Fainelli


On 2017年11月08日 02:26, Florian Fainelli wrote:
> On 11/07/2017 01:51 AM, Chris Zhong wrote:
>>
>> On 2017年11月07日 15:54, Vladimir Zapolskiy wrote:
>>> Hello Chris,
>>>
>>> On 11/07/2017 04:49 AM, Chris Zhong wrote:
>>>> The ethernet phy of rk3066a-rayeager has a reset pin, it controlled by
>>>> GPIO1_D6, this pin should be pull down then pull up to reset the phy.
>>>> Add a phy-reset property in emac, make the phy can be reset when emac
>>>> power on.
>>> for PHY reset there are properties 'reset-gpios' and 'reset-delay-us',
>>> please reference to Documentation/devicetree/bindings/net/mdio.txt
>>>
>>> Can you try to reuse them instead of adding new custom properties?
>> This phy-reset is from Documentation/devicetree/bindings/net/arc_emac.txt.
>> And copy from arch/arm/boot/dts/rk3036-kylin.dts.
>> Can we just use these properties, they are not new.
> Because it already exists does not mean it's correct, in fact, it is not
> at all because it places the reset property for a PHY into the MAC node,
> which is just not what this is, what we should be using instead is the
> following patch series:
>
> http://patchwork.ozlabs.org/project/netdev/list/?series=9267
>
> http://patchwork.ozlabs.org/patch/828499/
> http://patchwork.ozlabs.org/patch/828505/
> http://patchwork.ozlabs.org/patch/828501/
> http://patchwork.ozlabs.org/patch/828502/
Okay, this series works for me, and I will push a new version patch 
following it,
with a reset-gpios property under phy node.
And hope this series can be applied soon.

Thanks
Chris Zhong


>>> As a side question, which is mainly addressed to Sergei and Roger,
>>> I don't quite understand why PHY properties were initially added to
>>> MAC/MDIO bus device tree nodes, in my opinion they must be moved under
>>> PHY device tree nodes.
>>>
>>> -- 
>>> With best wishes,
>>> Vladimir
>>>
>>>> Signed-off-by: Chris Zhong <zyw@rock-chips.com>
>>>> ---
>>>>
>>>>    arch/arm/boot/dts/rk3066a-rayeager.dts | 2 ++
>>>>    1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/arch/arm/boot/dts/rk3066a-rayeager.dts
>>>> b/arch/arm/boot/dts/rk3066a-rayeager.dts
>>>> index 570157f..6064a0a 100644
>>>> --- a/arch/arm/boot/dts/rk3066a-rayeager.dts
>>>> +++ b/arch/arm/boot/dts/rk3066a-rayeager.dts
>>>> @@ -173,6 +173,8 @@
>>>>        pinctrl-0 = <&emac_xfer>, <&emac_mdio>, <&rmii_rst>;
>>>>        phy = <&phy0>;
>>>>        phy-supply = <&vcc_rmii>;
>>>> +    phy-reset-gpios = <&gpio1 RK_PD6 GPIO_ACTIVE_LOW>; /* PHY_RST */
>>>> +    phy-reset-duration = <10>; /* millisecond */
>>>>        status = "okay";
>>>>          phy0: ethernet-phy@0 {
>>>>
>>>
>