Re: [PATCH v2 2/3] dt-bindings: power: Add mediatek larb definition - Yu-chang Lee (李禹璋)

From: "Yu-chang Lee (李禹璋)" <Yu-chang.Lee@mediatek.com>
To: "krzysztof.kozlowski@linaro.org" <krzysztof.kozlowski@linaro.org>,
	"MandyJH Liu (劉人僖)" <MandyJH.Liu@mediatek.com>,
	"conor+dt@kernel.org" <conor+dt@kernel.org>,
	"robh@kernel.org" <robh@kernel.org>,
	"krzysztof.kozlowski+dt@linaro.org"
	<krzysztof.kozlowski+dt@linaro.org>,
	"matthias.bgg@gmail.com" <matthias.bgg@gmail.com>,
	"ulf.hansson@linaro.org" <ulf.hansson@linaro.org>,
	"angelogioacchino.delregno@collabora.com"
	<angelogioacchino.delregno@collabora.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-mediatek@lists.infradead.org"
	<linux-mediatek@lists.infradead.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
	Project_Global_Chrome_Upstream_Group
	<Project_Global_Chrome_Upstream_Group@mediatek.com>,
	"Xiufeng Li (李秀峰)" <Xiufeng.Li@mediatek.com>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	"Fan Chen (陳凡)" <fan.chen@mediatek.com>
Subject: Re: [PATCH v2 2/3] dt-bindings: power: Add mediatek larb definition
Date: Wed, 27 Mar 2024 09:34:13 +0000	[thread overview]
Message-ID: <f3eedfb3495bb9c28b5cbf466387c24822c5b6f6.camel@mediatek.com> (raw)
In-Reply-To: <c3ca3d90-898e-44b0-ad0f-dd78c09c5fcd@linaro.org>

On Wed, 2024-03-27 at 10:23 +0100, Krzysztof Kozlowski wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  On 27/03/2024 09:39, Krzysztof Kozlowski wrote:
> > On 27/03/2024 06:57, yu-chang.lee wrote:
> >> Add Smart Multimedia Interface Local Arbiter to mediatek
> >> power domain.
> >>
> >> Signed-off-by: yu-chang.lee <yu-chang.lee@mediatek.com>
> >> ---
> >>  .../devicetree/bindings/power/mediatek,power-controller.yaml  | 4
> ++++
> >>  1 file changed, 4 insertions(+)
> >>
> >> diff --git
> a/Documentation/devicetree/bindings/power/mediatek,power-
> controller.yaml
> b/Documentation/devicetree/bindings/power/mediatek,power-
> controller.yaml
> >> index 8985e2df8a56..228c0dec5253 100644
> >> --- a/Documentation/devicetree/bindings/power/mediatek,power-
> controller.yaml
> >> +++ b/Documentation/devicetree/bindings/power/mediatek,power-
> controller.yaml
> >> @@ -125,6 +125,10 @@ $defs:
> >>          $ref: /schemas/types.yaml#/definitions/phandle
> >>          description: phandle to the device containing the SMI
> register range.
> >>  
> >> +     mediatek,larb:
> >> +        $ref: /schemas/types.yaml#/definitions/phandle
> >> +        description: phandle to the device containing the LARB
> register range.
> > 
> > Why do you need it?
> > 
> > Plus I also see mediatek,larbs and mediatek,larb-id... so now we
> have
> > third one similar.
> 
> ... and not even tested!
> 
> Best regards,
> Krzysztof
> 
Hi,

I will double check the format of yaml for the next version, sorry for
inconvenience. But I did test it on mt8188 chromebook, the reason why
power domain need larb node is that when mtcmos power on, signal glitch
may produce. Power domain driver must reset larb when this happen to 
prevent dummy transaction on bus. That why I need larb node in dts.

Best Regards,
Yu-chang
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