Re: [PATCH v2 2/6] iio: imu: adis: Add irq mask variable

[Lars-Peter Clausen <lars@metafoo.de>]

On 3/16/20 1:53 PM, Nuno Sá wrote:
> There are some ADIS devices that can configure the data ready pin
> polarity. Hence, we cannot hardcode our IRQ mask as IRQF_TRIGGER_RISING
> since we might want to have it as IRQF_TRIGGER_FALLING.
>
> Signed-off-by: Nuno Sá <nuno.sa@analog.com>
> ---
> Changes in v2:
>   * Add kernel doc-string for `irq-mask`.
>
>   drivers/iio/imu/adis_trigger.c | 26 ++++++++++++++++++++++++--
>   include/linux/iio/imu/adis.h   |  2 ++
>   2 files changed, 26 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/imu/adis_trigger.c b/drivers/iio/imu/adis_trigger.c
> index 9e393819d238..21eddffc50d3 100644
> --- a/drivers/iio/imu/adis_trigger.c
> +++ b/drivers/iio/imu/adis_trigger.c
> @@ -34,6 +34,20 @@ static inline void adis_trigger_setup(struct adis *adis)
>   	iio_trigger_set_drvdata(adis->trig, adis);
>   }
>   
> +static inline int __adis_validate_irq_mask(struct adis *adis)

Bit of a nitpick, I'd drop the __ prefix, so far we only used it if 
there is a locked and an unlocked version of a function and it is 
unlikely that we'll need an unlocked function here.

I'd also drop the inline the compiler is smart enough to figure this out 
on its own. I believe the recommendation at the moment for kernel code 
is to use inline only for functions defined in header files.

> +{
> +	if (!adis->irq_mask) {
> +		adis->irq_mask = IRQF_TRIGGER_RISING;
> +		return 0;
> +	} else if (adis->irq_mask != IRQF_TRIGGER_RISING &&
> +		   adis->irq_mask != IRQF_TRIGGER_FALLING) {
> +		dev_err(&adis->spi->dev, "Invalid IRQ mask:%08lx\n",

Another nitpick. Space behind the ":".

> +			adis->irq_mask);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
>   /**
>    * adis_probe_trigger() - Sets up trigger for a adis device
>    * @adis: The adis device
> @@ -54,9 +68,13 @@ int adis_probe_trigger(struct adis *adis, struct iio_dev *indio_dev)
>   
>   	adis_trigger_setup(adis);
>   
> +	ret = __adis_validate_irq_mask(adis);
> +	if (ret)
> +		return ret;
> +
>   	ret = request_irq(adis->spi->irq,
>   			  &iio_trigger_generic_data_rdy_poll,
> -			  IRQF_TRIGGER_RISING,
> +			  adis->irq_mask,
>   			  indio_dev->name,
>   			  adis->trig);
>   	if (ret)
> @@ -96,9 +114,13 @@ int devm_adis_probe_trigger(struct adis *adis, struct iio_dev *indio_dev)
>   
>   	adis_trigger_setup(adis);
>   
> +	ret = __adis_validate_irq_mask(adis);
> +	if (ret)
> +		return ret;
> +
>   	ret = devm_request_irq(&adis->spi->dev, adis->spi->irq,
>   			       &iio_trigger_generic_data_rdy_poll,
> -			       IRQF_TRIGGER_RISING,
> +			       adis->irq_mask,
>   			       indio_dev->name,
>   			       adis->trig);
>   	if (ret)
> diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h
> index ac94c483bf2b..ed41c6b96d14 100644
> --- a/include/linux/iio/imu/adis.h
> +++ b/include/linux/iio/imu/adis.h
> @@ -87,6 +87,7 @@ struct adis_data {
>    * @msg: SPI message object
>    * @xfer: SPI transfer objects to be used for a @msg
>    * @current_page: Some ADIS devices have registers, this selects current page
> + * @irq_mask: IRQ handling flags as passed to request_irq()
>    * @buffer: Data buffer for information read from the device
>    * @tx: DMA safe TX buffer for SPI transfers
>    * @rx: DMA safe RX buffer for SPI transfers
> @@ -113,6 +114,7 @@ struct adis {
>   	struct spi_message	msg;
>   	struct spi_transfer	*xfer;
>   	unsigned int		current_page;
> +	unsigned long		irq_mask;
>   	void			*buffer;
>   
>   	uint8_t			tx[10] ____cacheline_aligned;