staging:iio-trig-periodic-rtc: Allow to reset frequency to 0
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>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
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 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 @@
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;
