RE: [PATCH 3/3] dt-bindings: rcar-gen3-phy-usb2: Add r7s9210 support

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>,
	Chris Brandt <Chris.Brandt@renesas.com>
Cc: Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	Simon Horman <horms+renesas@verge.net.au>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
	<devicetree@vger.kernel.org>,
	linux-clk <linux-clk@vger.kernel.org>
Subject: RE: [PATCH 3/3] dt-bindings: rcar-gen3-phy-usb2: Add r7s9210 support
Date: Wed, 14 Nov 2018 12:05:56 +0000	[thread overview]
Message-ID: <OSBPR01MB2293042419890D6EECA0C9A2D8C30@OSBPR01MB2293.jpnprd01.prod.outlook.com> (raw)
In-Reply-To: <CAMuHMdX7_bk4b7WTmxDuLPR=-WZYdbt=7P2e-gs4ZOT=-EzL-g@mail.gmail.com>

Hi Geert-san,

> From: Geert Uytterhoeven, Sent: Wednesday, November 14, 2018 8:03 PM
> 
> Hi Chris,
> 
> On Wed, Nov 7, 2018 at 6:36 PM Chris Brandt <chris.brandt@renesas.com> wrote:
<snip>
> > @@ -16,8 +18,8 @@ Required properties:
> >               R8A77990 SoC.
> >               "renesas,usb2-phy-r8a77995" if the device is a part of an
> >               R8A77995 SoC.
> > -             "renesas,rcar-gen3-usb2-phy" for a generic R-Car Gen3 or RZ/G2
> > -             compatible device.
> > +             "renesas,rcar-gen3-usb2-phy" for a generic R-Car Gen3, RZ/G2 or
> > +             RZ/A2 compatible device.
> 
> Is it a good idea to declare RZ/A2 compatible to R-Car Gen3?
> Usually we don't do that for Renesas IP cores used in different families[*].
> Of course, I know you do have a good relationship with the actual RZ/A2
> hardware designers ;-)
> 
> In light of Shimoda-san's comment w.r.t. R-Car H3 USB port1 in the driver
> code, perhaps "renesas,rcar-gen3-usb2-phy" should not be used?

Sorry for lack explanation. 
 - The default value of COMMCTRL on each port of R-Car Gen3 is the same (0x80000000).
 - However, R-Car H3 USB port1 seems to ignore this value because
   the port always acts as host. If I changed the register to 0 on R-Car H3 ES3.0,
   the port1 can work as host.

So, I meant all "renesas,rcar-gen3-usb2-phy" devices without "is_otg_channel"
can set the COMMCTRL register to 0.

Of course, adding a new RZ/A2 family compatible is OK to me.

Best regards,
Yoshihiro Shimoda

> [*] Sole exceptions I'm aware of are:
>       - "renesas,rmobile-iic", in addition to "renesas,rcar-gen2-iic" or
>         "renesas,rcar-gen3-iic" on R-Car Gen2/3,
>       - "renesas,rcar-gen2-cmt1" and "renesas,rcar-thermal" on R-Mobile APE6.
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
> 
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
> 
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds