Re: [PATCH v2 1/2] thermal/drivers/rcar_gen3: Handle -ENXIO from optional IRQ lookup

[Niklas Söderlund]

Hi Bui,

Thanks for your work.

On 2026-08-10 18:18:40 +0700, phucduc.bui@xxxxxxxxx wrote:
> From: bui duc phuc <phucduc.bui@xxxxxxxxx>
> 
> rcar_gen3_thermal_request_irqs() may return -ENXIO when no optional
> IRQ is available. The caller currently treats all negative return values
> the same way, disabling hardware trip-point support and continuing probe.
> 
> Distinguish -ENXIO from other errors so that the existing behavior is
> preserved when the optional IRQ is absent, while errors such as
> -EPROBE_DEFER, -EINVAL, and other failures are propagated to the
> caller.
> 
> Signed-off-by: bui duc phuc <phucduc.bui@xxxxxxxxx>
> ---
> 
> Link v1 : 
> https://lore.kernel.org/all/20260807093058.42840-1-phucduc.bui@xxxxxxxxx/
> Changes in v2: 
>  - Update the commit message.
>  - Move error handling to the caller.
> 
>  drivers/thermal/renesas/rcar_gen3_thermal.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/thermal/renesas/rcar_gen3_thermal.c b/drivers/thermal/renesas/rcar_gen3_thermal.c
> index 94804816e9e1..04a57ff724f4 100644
> --- a/drivers/thermal/renesas/rcar_gen3_thermal.c
> +++ b/drivers/thermal/renesas/rcar_gen3_thermal.c
> @@ -527,8 +527,11 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev)
>  	priv->info = of_device_get_match_data(dev);
>  	platform_set_drvdata(pdev, priv);
>  
> -	if (rcar_gen3_thermal_request_irqs(priv, pdev))
> +	ret = rcar_gen3_thermal_request_irqs(priv, pdev);
> +	if (ret == -ENXIO)
>  		priv->ops.set_trips = NULL;
> +	else if (ret)
> +		return ret;

I'm not sure I like this.

The old behavior is that for any reason we can't get the optional IRQ 
the driver still works, but without hardware trip points.

While the new behavior is that if *something* other then the IRQ not 
being available we fail probe. What is the gain here? What benefit is 
there from the driver not providing thermal readouts if say for example 
getting the optional IRQ would return -EINVAL ?

>  
>  	pm_runtime_enable(dev);
>  	pm_runtime_get_sync(dev);
> -- 
> 2.43.0
> 

-- 
Kind Regards,
Niklas Söderlund