Re: [PATCH 1/3] phy: phy-can-transceiver: default silent GPIO to high during probe

Marc Kleine-Budde <[email protected]> Thu, 30 Jul 2026 08:12:46 +0200

Newsgroups	org.kernel.vger.linux-can,dev.linux.lists.imx,org.infradead.lists.linux-arm-kernel,org.infradead.lists.linux-phy,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel
Message-ID	<[email protected]>

On 30.07.2026 12:33:26, [email protected] wrote:
> From: Haibo Chen <[email protected]>
>
> The silent pin of the CAN transceiver is active high, asserting it puts
> the transceiver into silent (listen-only) mode where the transmitter is
> disabled.
>
> At probe time, and before the PHY is powered on, the transceiver should
> default to silent mode. This is the correct and lower-power state: the
> transceiver should not actively drive the CAN bus until the PHY is
> explicitly powered on. Requesting the silent GPIO as GPIOD_OUT_LOW leaves
> the transceiver in normal mode by default, which is both incorrect and
> wastes power.
>
> Request the silent GPIO as GPIOD_OUT_HIGH so the transceiver starts in
> silent mode, and let the power_on/power_off callbacks manage the mode
> afterwards.
>
> Signed-off-by: Haibo Chen <[email protected]>

Reviewed-by: Marc Kleine-Budde <[email protected]>

regards,
Marc

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