Hi Biju,
On Mon, 14 Apr 2025 at 17:53, Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> > From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > > -----Original Message-----
> > > From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> > > Sent: 14 April 2025 16:39
> > > Subject: Re: [PATCH v2 2/3] arm64: dts: renesas: r9a09g047e57-smarc:
> > > Enable CANFD
> > >
> > > On Thu, 20 Mar 2025 at 17:41, Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> > > > Enable CANFD on the RZ/G3E SMARC EVK platform.
> > > >
> > > > Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > > > ---
> > > > v1->v2:
> > > > * Split the patch into two.
> > > > * Enabling CANFD done in this patch and CAN Transceiver on next patch.
> > > > * Defined the macros SW_LCD_EN and SW_PDM_EN which routes signals to
> > > > CAN0 and CAN1 based on SYS.5 and BOOT.6 switches.
> > >
> > > Thanks for the update!
> > >
> > > > --- a/arch/arm64/boot/dts/renesas/r9a09g047e57-smarc.dts
> > > > +++ b/arch/arm64/boot/dts/renesas/r9a09g047e57-smarc.dts
> > > > @@ -8,6 +8,8 @@
> > > > /dts-v1/;
> > > >
> > > > /* Switch selection settings */
> > > > +#define SW_LCD_EN 0
> > > > +#define SW_PDM_EN 0
> > > > #define SW_SD0_DEV_SEL 0
> > > > #define SW_SDIO_M2E 0
> > > >
> > > > @@ -33,7 +35,36 @@ vqmmc_sd1_pvdd: regulator-vqmmc-sd1-pvdd {
> > > > };
> > > > };
> > > >
> > > > +&canfd {
> > > > + pinctrl-0 = <&canfd_pins>;
> > > > + pinctrl-names = "default";
> > > > +
> > > > +#if (!SW_PDM_EN)
> > > > + channel1 {
> > > > + status = "okay";
> > > > + };
> > > > +#endif
> > > > +
> > > > +#if (!SW_LCD_EN)
> > > > + channel4 {
> > > > + status = "okay";
> > > > + };
> > > > +#endif
> > > > +};
> > > > +
> > > > &pinctrl {
> > > > + canfd_pins: canfd {
> > > > + can1_pins: can1 {
> > > > + pinmux = <RZG3E_PORT_PINMUX(L, 2, 3)>, /* RX */
> > > > + <RZG3E_PORT_PINMUX(L, 3, 3)>; /* TX */
> > > > + };
> > > > +
> > > > + can4_pins: can4 {
> > > > + pinmux = <RZG3E_PORT_PINMUX(5, 2, 3)>, /* RX */
> > > > + <RZG3E_PORT_PINMUX(5, 3, 3)>; /* TX */
> > > > + };
> > > > + };
> > > > +
> > > > scif_pins: scif {
> > > > pins = "SCIF_TXD", "SCIF_RXD";
> > > > renesas,output-impedance = <1>; diff --git
> > > > a/arch/arm64/boot/dts/renesas/renesas-smarc2.dtsi
> > > > b/arch/arm64/boot/dts/renesas/renesas-smarc2.dtsi
> > > > index fd82df8adc1e..1d3a844174b3 100644
> > > > --- a/arch/arm64/boot/dts/renesas/renesas-smarc2.dtsi
> > > > +++ b/arch/arm64/boot/dts/renesas/renesas-smarc2.dtsi
> > > > @@ -29,6 +29,10 @@ aliases {
> > > > };
> > > > };
> > > >
> > > > +&canfd {
> > > > + status = "okay";
> > > > +};
> > >
> > > I am wondering why you split this in two patches?
> > > I believe CAN-FD does not work without adding the CAN transceivers,
> > > which is only done in the next patch?
> >
> > STB pin is active high. If you see the schematic GPIO8 and GPIO9 are controlled through a switch.
> >
> > By default, they are set to GPIO8_PMOD and GPIO9_PMOD, meaning STB pins are pulled Down.
> > So, with CAN transceiver driver still we can test CANFD.
>
> Typo with->without.
Thanks, the pull-downs on GPIO8_CAN0_STB and GPIO9_CAN1_STB will indeed
do the trick.
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
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
