Re: [PATCH] arm64: dts: imx91-11x11-frdm: fix CAN transceiver gpio

[Francesco Valla <francesco@valla.it>]

Hi Daniel,

On Fri, Jan 16, 2026 at 01:40:11PM +0200, Daniel Baluta wrote:
> On Thu, Jan 15, 2026 at 8:25 PM Francesco Valla <francesco@valla.it> wrote:
> >
> > According to the HW schematic, the CAN transceiver does not have an
> > enable pin but a silent one. Fix the GPIO property name and polarity.
> >
> > Fixes: b4bf5e55899e ("arm64: dts: freescale: Add FRDM-IMX91 basic support")
> 
> Just for clarification GPIO 23 is connected to a pin named CAN_STBY.
> So I wonder if it isn't
> better to use standby-gpios instead of silent-gpios?
> 
> I am looking at FRDM-IMX91 schematic file SPF-94610_A1.pdf.
> 
> But on the other hand we have
> 
> static const struct can_transceiver_data tja1051_drvdata = {
> »       .flags = CAN_TRANSCEIVER_SILENT_PRESENT | CAN_TRANSCEIVER_EN_PRESENT,
> };
> 
> So TJA1051 is not advertised as having a stdby flag.

Regardless of the name of the net, the functionality of a standby vs a
silent pin is very different. In this case, since the TJA1051 is
including a silent pin (pin S in he datasheet [0]), I think it's better
to declare it that way.

In case someone adds the support for a phy-oriented listen-only mode
(which is something I am thinking), this wouldn't break the integartion.

Regards,
Francesco

[0] https://www.nxp.com/docs/en/data-sheet/TJA1051.pdf