Re: [PATCH 1/3] drivers: thermal: tsens: Add critical interrupt support

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Mon 11 Nov 11:21 PST 2019, Amit Kucheria wrote:

> TSENS IP v2.x adds critical threshold interrupt support for each sensor
> in addition to the upper/lower threshold interrupt. Add support in the
> driver.
> 
> Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
> ---
>  drivers/thermal/qcom/tsens-common.c | 129 ++++++++++++++++++++++++++--
>  drivers/thermal/qcom/tsens-v2.c     |   8 +-
>  drivers/thermal/qcom/tsens.c        |  21 +++++
>  drivers/thermal/qcom/tsens.h        |  73 ++++++++++++++++
>  4 files changed, 220 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> index 4359a4247ac3..2989cb952cdb 100644
> --- a/drivers/thermal/qcom/tsens-common.c
> +++ b/drivers/thermal/qcom/tsens-common.c
> @@ -23,6 +23,10 @@
>   * @low_thresh:     lower threshold temperature value
>   * @low_irq_mask:   mask register for lower threshold irqs
>   * @low_irq_clear:  clear register for lower threshold irqs
> + * @crit_viol:      critical threshold violated

"violated" as in "temperature is above crit_thresh"?

> + * @crit_thresh:    critical threshold temperature value
> + * @crit_irq_mask:  mask register for critical threshold irqs
> + * @crit_irq_clear: clear register for critical threshold irqs
>   *
[..]
> diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> index 7d317660211e..784c4976c4f9 100644
> --- a/drivers/thermal/qcom/tsens.c
> +++ b/drivers/thermal/qcom/tsens.c
> @@ -121,6 +121,27 @@ static int tsens_register(struct tsens_priv *priv)
>  
>  	enable_irq_wake(irq);
>  
> +	if (tsens_version(priv) > VER_1_X) {
> +		irq = platform_get_irq_byname(pdev, "critical");
> +		if (irq < 0) {

Treating this as a fatal error breaks backwards compatibility with
current devicetree; and even within your patch series, tsens should fail
to probe between this patch and the application of patch 3.

Please flip this around and do:

irq = platform_get_irq_byname(pdev, "critical");
if (irq >= 0 && tsens_version(priv) > VER_1_X) {
	request_irq()...
}

> +			ret = irq;
> +			goto err_put_device;
> +		}
> +
> +		ret = devm_request_threaded_irq(&pdev->dev, irq,
> +						NULL, tsens_critical_irq_thread,
> +						IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> +						dev_name(&pdev->dev), priv);
> +		if (ret) {
> +			dev_err(&pdev->dev, "%s: failed to get critical irq\n", __func__);
> +			goto err_put_device;
> +		}
> +
> +		enable_irq_wake(irq);
> +	}
> +
> +	return 0;
> +
>  err_put_device:
>  	put_device(&pdev->dev);
>  	return ret;

Regards,
Bjorn