Re: [PATCH v7 2/2] can: m_can: add ti,am62-mcan compatible with out-of-band wakeup support

[Markus Schneider-Pargmann]

Hi Kendall,

On Thu Sep 24, 2026 at 11:54 PM CEST, Kendall Willis wrote:
> In TI K3 AM62 SoCs, the M_CAN controllers are in power domains which are
> OFF in the deepest low power states. However, the m_can pins are able to
> wakeup the system from states where the power domain is OFF through its
> out-of-band wakeup functionality.
>
> Introduce the ti,am62-mcan compatible with match data to identify the
> out-of-band wakeup capability for TI AM62 SoCs. During suspend, set the
> out-of-band wakeup flag when the device is configured as a wakeup
> source, the "wakeup" pinctrl state is present, and the match data
> indicates out-of-band wakeup support.
>
> Signed-off-by: Kendall Willis <k-willis@xxxxxx>
> ---
>  drivers/net/can/m_can/m_can.c          | 10 ++++++++--
>  drivers/net/can/m_can/m_can.h          |  6 ++++++
>  drivers/net/can/m_can/m_can_platform.c |  9 +++++++++
>  3 files changed, 23 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
> index 91a0c5eca260c19fa97c6f5724341cad0c1c95b8..815a11531ff47b8460aa3efa3075804b4f769848 100644
> --- a/drivers/net/can/m_can/m_can.c
> +++ b/drivers/net/can/m_can/m_can.c
> @@ -2628,8 +2628,14 @@ int m_can_class_suspend(struct device *dev)
>  		cdev->can.state = CAN_STATE_SLEEPING;
>  	}
>  
> -	if (!m_can_class_wakeup_pinctrl_enabled(cdev))
> -		pinctrl_pm_select_sleep_state(dev);
> +	if (!ret) {

I guess this !ret is from an earlier iteration? Code at this point is
only executed if everything was successful so far. So I think you can
drop this outer if.

> +		if (m_can_class_wakeup_pinctrl_enabled(cdev)) {
> +			if (cdev->out_band_wakeup)
> +				device_set_out_band_wakeup(dev);
> +		} else {
> +			pinctrl_pm_select_sleep_state(dev);
> +		}
> +	}
>  
>  	return 0;
>  
> diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
> index 4743342b2fba3823819b9e2bc5b085cc0fe6d1e2..da64e6bbcef2a721a330e67fd852ca4a703c5794 100644
> --- a/drivers/net/can/m_can/m_can.h
> +++ b/drivers/net/can/m_can/m_can.h
> @@ -132,6 +132,12 @@ struct m_can_classdev {
>  
>  	struct pinctrl *pinctrl;
>  	struct pinctrl_state *pinctrl_state_wakeup;
> +
> +	bool out_band_wakeup;
> +};
> +
> +struct m_can_of_data {
> +	bool out_band_wakeup;

Can you please move struct m_can_of_data to the top of m_can_platform.c
to keep it local to where it is used?

The rest looks good to me.

Best
Markus

>  };
>  
>  struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, int sizeof_priv);
> diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
> index 51dd41dbf2c9a971295994946e190ec0187addd5..dbd59730c0bc16f519cb2c40bcd8093ca1bcb369 100644
> --- a/drivers/net/can/m_can/m_can_platform.c
> +++ b/drivers/net/can/m_can/m_can_platform.c
> @@ -83,6 +83,7 @@ static int m_can_plat_probe(struct platform_device *pdev)
>  	void __iomem *addr;
>  	void __iomem *mram_addr;
>  	struct phy *transceiver;
> +	const struct m_can_of_data *of_data;
>  	int irq = 0, ret = 0;
>  
>  	mcan_class = m_can_class_allocate_dev(&pdev->dev,
> @@ -148,6 +149,9 @@ static int m_can_plat_probe(struct platform_device *pdev)
>  
>  	mcan_class->is_peripheral = false;
>  
> +	of_data = of_device_get_match_data(&pdev->dev);
> +	mcan_class->out_band_wakeup = of_data && of_data->out_band_wakeup;
> +
>  	platform_set_drvdata(pdev, mcan_class);
>  
>  	pm_runtime_enable(mcan_class->dev);
> @@ -218,8 +222,13 @@ static const struct dev_pm_ops m_can_pmops = {
>  	SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)
>  };
>  
> +static const struct m_can_of_data m_can_plat_am62 = {
> +	.out_band_wakeup = true,
> +};
> +
>  static const struct of_device_id m_can_of_table[] = {
>  	{ .compatible = "bosch,m_can", .data = NULL },
> +	{ .compatible = "ti,am62-mcan", .data = &m_can_plat_am62 },
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, m_can_of_table);

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