Re: [PATCH v2 12/12] staging:iio-trig-periodic-rtc: Allow to reset frequency to 0

[Jonathan Cameron <jic23@kernel.org>]

On 12/06/14 06:00, Peter Meerwald wrote:
> periodic rtc trigger initially has frequency 0
>
> it is possible to change trigger frequency on-the-fly, but it is not
> possible to set frequency back to 0
>
> this patch allows to set trigger frequency to 0, thereby disabling
> the rtc interrupt
>
> Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Applied to the togreg branch of iio.git

thanks,
> ---
>   drivers/staging/iio/trigger/iio-trig-periodic-rtc.c | 19 ++++++++++++++++---
>   1 file changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c b/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c
> index 362a54a..b5108a1 100644
> --- a/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c
> +++ b/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c
> @@ -26,16 +26,22 @@ struct iio_prtc_trigger_info {
>   	struct rtc_device *rtc;
>   	int frequency;
>   	struct rtc_task task;
> +	bool state;
>   };
>
>   static int iio_trig_periodic_rtc_set_state(struct iio_trigger *trig, bool state)
>   {
>   	struct iio_prtc_trigger_info *trig_info = iio_trigger_get_drvdata(trig);
> -	if (trig_info->frequency == 0)
> +	int ret;
> +	if (trig_info->frequency == 0 && state)
>   		return -EINVAL;
>   	dev_dbg(&trig_info->rtc->dev, "trigger frequency is %d\n",
>   			trig_info->frequency);
> -	return rtc_irq_set_state(trig_info->rtc, &trig_info->task, state);
> +	ret = rtc_irq_set_state(trig_info->rtc, &trig_info->task, state);
> +	if (ret == 0)
> +		trig_info->state = state;
> +
> +	return ret;
>   }
>
>   static ssize_t iio_trig_periodic_read_freq(struct device *dev,
> @@ -61,7 +67,14 @@ static ssize_t iio_trig_periodic_write_freq(struct device *dev,
>   	if (ret)
>   		goto error_ret;
>
> -	ret = rtc_irq_set_freq(trig_info->rtc, &trig_info->task, val);
> +	if (val > 0) {
> +		ret = rtc_irq_set_freq(trig_info->rtc, &trig_info->task, val);
> +		if (ret == 0 && trig_info->state && trig_info->frequency == 0)
> +			ret = rtc_irq_set_state(trig_info->rtc, &trig_info->task, 1);
> +	} else if (val == 0) {
> +		ret = rtc_irq_set_state(trig_info->rtc, &trig_info->task, 0);
> +	} else
> +		ret = -EINVAL;
>   	if (ret)
>   		goto error_ret;
>
>