[v3,5/5] arm64: dts: renesas: r9a07g044: Enable sci0 nodes using dt overlay

Enable sci0 node using dt overlay and disable can{0,1}-stb-hog
nodes in dt overlay as its pins are shared with sci0 pins.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v3:
 * New patch
---
 arch/arm64/boot/dts/renesas/Makefile          |  1 +
 .../boot/dts/renesas/r9a07g043-smarc.dtso     | 45 +++++++++++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 arch/arm64/boot/dts/renesas/r9a07g043-smarc.dtso

Hi Geert,

Thanks for the feedback.

> -----Original Message-----
> From: Geert Uytterhoeven <geert@linux-m68k.org>
> Sent: Monday, March 20, 2023 7:15 PM
> To: Biju Das <biju.das.jz@bp.renesas.com>
> Cc: Rob Herring <robh+dt@kernel.org>; Krzysztof Kozlowski
> <krzysztof.kozlowski+dt@linaro.org>; Geert Uytterhoeven
> <geert+renesas@glider.be>; Magnus Damm <magnus.damm@gmail.com>; linux-
> renesas-soc@vger.kernel.org; devicetree@vger.kernel.org; Prabhakar Mahadev
> Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Subject: Re: [PATCH v3 5/5] arm64: dts: renesas: r9a07g044: Enable sci0
> nodes using dt overlay
> 
> Hi Biju,
> 
> On Mon, Mar 20, 2023 at 11:54 AM Biju Das <biju.das.jz@bp.renesas.com>
> wrote:
> > Enable sci0 node using dt overlay and disable can{0,1}-stb-hog nodes
> > in dt overlay as its pins are shared with sci0 pins.
> >
> > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v3:
> >  * New patch
> 
> Thanks for your patch!
> 
> > --- /dev/null
> > +++ b/arch/arm64/boot/dts/renesas/r9a07g043-smarc.dtso
> 
> Can you please come up with a better filename?
> Perhaps r9a07g043-smarc-pmod.dtso?

Agreed.

> 
> > @@ -0,0 +1,45 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Device Tree Source for the RZ/{G2UL, Five} SMARC EVK PMOD parts
> > + *
> > + * Copyright (C) 2023 Renesas Electronics Corp.
> > + *
> > + *
> > + * [Connection]
> > + *
> > + * SMARC EVK                           PMOD USBUART
> > + * +----------------------------+
> > + * |CN7 (PMOD1 PIN HEADER)     |
> > + * |   SCI0_TXD          pin7  |<----->| pin2  Tx      |
> > + * |   SCI1_RXD          pin8  |<----->| pin3  Rx      |
Typo SCI0_RXD
> > + * |   Gnd               pin11 |<----->| pin5  Gnd     |
> > + * |   Vcc               pin12 |<----->| pin6  Vcc     |
> > + * +----------------------------+      +---------------+
> 
> I don't think the right side of this diagram belongs here. The user is not
> limited to a USB-UART bridge, but can connect whatever he wants to the PMOD
> connector.

Agreed.

> 
> > + *
> > + */
> > +
> > +/dts-v1/;
> > +/plugin/;
> > +#include <dt-bindings/gpio/gpio.h>
> 
> Unused?

OK, will drop.
> 
> > +#include <dt-bindings/pinctrl/rzg2l-pinctrl.h>
> > +
> > +&pinctrl {
> > +       can0-stb-hog {
> > +               status = "disabled";
> > +       };
> > +
> > +       can1-stb-hog {
> > +               status = "disabled";
> > +       };
> > +
> > +       sci0_pins: sci0-pins {
> > +               pinmux = <RZG2L_PORT_PINMUX(2, 2, 5)>, /* TxD */
> > +                        <RZG2L_PORT_PINMUX(2, 3, 5)>; /* RxD */
> > +       };

Next version, I am planning to move this pinctrl definitions to rzg2ul-smarc-pinfunction.dtsi
as separate patch, since it is SoC specific?

+++ b/arch/arm64/boot/dts/renesas/rzg2ul-smarc-pinfunction.dtsi
@@ -50,6 +50,13 @@ i2c1_pins: i2c1 {
                input-enable;
        };
 
+#if (SW_ET0_EN_N)
+       sci0_pins: sci0-pins {
+               pinmux = <RZG2L_PORT_PINMUX(2, 2, 5)>, /* TxD */
+                        <RZG2L_PORT_PINMUX(2, 3, 5)>; /* RxD */
+       };
+#endif

Cheers,
Biju

> > +};
> > +
> > +&sci0 {
> > +       pinctrl-0 = <&sci0_pins>;
> > +       pinctrl-names = "default";
> > +       status = "okay";
> > +};
> 
> 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