Re: [PATCH V2 7/9] interconnect: imx: set of_node for interconnect provider

From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Lucas Stach <l.stach@pengutronix.de>
Cc: "Peng Fan (OSS)" <peng.fan@oss.nxp.com>,
	djakov@kernel.org, shawnguo@kernel.org, s.hauer@pengutronix.de,
	festevam@gmail.com, robh+dt@kernel.org,
	krzysztof.kozlowski+dt@linaro.org, abel.vesa@nxp.com,
	abailon@baylibre.com, marex@denx.de, paul.elder@ideasonboard.com,
	Markus.Niebel@ew.tq-group.com, aford173@gmail.com,
	kernel@pengutronix.de, linux-pm@vger.kernel.org,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-imx@nxp.com,
	abelvesa@kernel.org, Peng Fan <peng.fan@nxp.com>
Subject: Re: [PATCH V2 7/9] interconnect: imx: set of_node for interconnect provider
Date: Wed, 29 Jun 2022 20:32:39 +0300	[thread overview]
Message-ID: <YryMt4CfQNkIHwiV@pendragon.ideasonboard.com> (raw)
In-Reply-To: <3c773637f626877832041d3065f387261ba70816.camel@pengutronix.de>

On Wed, Jun 29, 2022 at 05:08:58PM +0200, Lucas Stach wrote:
> Am Donnerstag, dem 16.06.2022 um 15:33 +0800 schrieb Peng Fan (OSS):
> > From: Peng Fan <peng.fan@nxp.com>
> > 
> > The provider device is created using platform_device_register_data in
> > imx-bus driver, which not has of_node. With of_node set, it will be
> > easy to support QoS settings.
> > 
> That's a bit dangerous, as sharing a of_node between two devices can
> lead to some reference counting issues IIRC, but then I also don't see
> a good way to do this any differently.
> 
> Regards,
> Lucas
> 
> > Signed-off-by: Peng Fan <peng.fan@nxp.com>
> > ---
> >  drivers/interconnect/imx/imx.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/interconnect/imx/imx.c b/drivers/interconnect/imx/imx.c
> > index 1f16eedea21c..78557fe6da2c 100644
> > --- a/drivers/interconnect/imx/imx.c
> > +++ b/drivers/interconnect/imx/imx.c
> > @@ -264,6 +264,7 @@ int imx_icc_register(struct platform_device *pdev,
> >  	provider->xlate = of_icc_xlate_onecell;
> >  	provider->data = data;
> >  	provider->dev = dev->parent;
> > +	provider->dev->of_node = dev->parent->of_node;

Due to the previous line, provider->dev is equal to dev->parent, so
doesn't this essentially do

	dev->parent->of_node = dev->parent->of_node;

which is a no-op ?

> >  	platform_set_drvdata(pdev, imx_provider);
> >  
> >  	ret = icc_provider_add(provider);

-- 
Regards,

Laurent Pinchart