From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 28 Mar 2019 10:33:53 -0500 From: Rob Herring Subject: Re: [PATCH v2 2/7] dt-bindings: usb: renesas_usb3: add usb-role-switch property Message-ID: <20190328153353.GA3070@bogus> References: <1552552775-51667-1-git-send-email-biju.das@bp.renesas.com> <1552552775-51667-3-git-send-email-biju.das@bp.renesas.com> <20190314105347.GC7752@kuha.fi.intel.com> <20190315105146.GI7752@kuha.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190315105146.GI7752@kuha.fi.intel.com> To: Heikki Krogerus Cc: Biju Das , Yoshihiro Shimoda , Mark Rutland , Greg Kroah-Hartman , Felipe Balbi , "linux-usb@vger.kernel.org" , "devicetree@vger.kernel.org" , Simon Horman , Geert Uytterhoeven , Chris Paterson , Fabrizio Castro , "linux-renesas-soc@vger.kernel.org" List-ID: On Fri, Mar 15, 2019 at 12:51:46PM +0200, Heikki Krogerus wrote: > Thanks, > > On Fri, Mar 15, 2019 at 09:08:19AM +0000, Biju Das wrote: > > > Subject: Re: [PATCH v2 2/7] dt-bindings: usb: renesas_usb3: add usb-role- > > > > > > a/Documentation/devicetree/bindings/usb/renesas_usb3.txt > > > > > > b/Documentation/devicetree/bindings/usb/renesas_usb3.txt > > > > > > index 35039e7..eecaf4c 100644 > > > > > > --- a/Documentation/devicetree/bindings/usb/renesas_usb3.txt > > > > > > +++ b/Documentation/devicetree/bindings/usb/renesas_usb3.txt > > > > > > @@ -22,6 +22,7 @@ Required properties: > > > > > > Optional properties: > > > > > > - phys: phandle + phy specifier pair > > > > > > - phy-names: must be "usb" > > > > > > + - usb-role-switch: use USB role switch to support dual-role > > > > > > + switch > > > > > > > > > > I don't think we can add such a property. At least, we have to add > > > "renesas," > > > > > prefix. > > > > > > > > usb_role_switch_get api uses "usb-role-switch" property to get role > > > switch linked with the device. > > > > > > > > HD3SS3220 port controller driver gets role switch handle linked with the > > > device using usb_role_switch_get api. > > > > That is the reason, I have added " usb-role-switch" property here. > > > > > > > > Do you have any other suggestion to get usb role switch handle? > > > > > > We can still change the API. Can we use the compatible for this? > > > > Do you mean usb_role_switch_get API needs to handle compatible "usb-x-connector" wherex= a,b ,c ? > > Then it uses the graphs api to get the device linked with it and return the usb role switch handle. > > In that case, no need to add generic "usb-role-switch" property here. > > > > Can you please confirm my understanding is correct? > > No, I meant the compatible property would have the value > "usb-role-switch". Your compatible would probable look something > like this: > > compatible = "renesas,r8a774c0-usb3-peri", > "usb-role-switch"; > > So the idea would be that the device supplying USB role switch > functionality, in your case the USB controller, would need to have the > compatible property containing "usb-role-switch". That's not really something a driver could bind to nor provides any info as to what the h/w is (and how to interact with it). > > I'm really not an expert in DT, so I don't know if that is acceptable. > Rob can you comment on this? I would go with Biju's proposal. Rob