On Tue, 28 Jul 2015, Vladimir Barinov wrote:
> Add periodic polling functionality to SYSFS trigger
typos below
> Signed-off-by: Vladimir Barinov <vladimir.bari...@cogentembedded.com>
> ---
> Changes in version 2:
> - initially added
>
> .../ABI/testing/sysfs-bus-iio-trigger-sysfs | 11 ++++
> drivers/iio/trigger/iio-trig-sysfs.c | 58
> ++++++++++++++++++++++
> 2 files changed, 69 insertions(+)
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-trigger-sysfs
> b/Documentation/ABI/testing/sysfs-bus-iio-trigger-sysfs
> index 5235e6c..49caff2 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio-trigger-sysfs
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-trigger-sysfs
> @@ -9,3 +9,14 @@ Description:
> automated testing or in situations, where other trigger methods
> are not applicable. For example no RTC or spare GPIOs.
> X is the IIO index of the trigger.
> +
> +What: /sys/bus/iio/devices/triggerX/trigger_poll
> +KernelVersion: 4.2.0
> +Contact: linux-...@vger.kernel.org
> +Description:
> + This file is provided by the iio-trig-sysfs stand-alone trigger
> + driver. Writing this file with positive value (in milliseconds)
> + will start peroidic event triggereing of the driver, associated
periodic
triggering
> + with this trigger. Writing this file with 0 will stop perioding
> + triggering.
> + X is the IIO index of the trigger.
> diff --git a/drivers/iio/trigger/iio-trig-sysfs.c
> b/drivers/iio/trigger/iio-trig-sysfs.c
> index 3dfab2b..ea79311 100644
> --- a/drivers/iio/trigger/iio-trig-sysfs.c
> +++ b/drivers/iio/trigger/iio-trig-sysfs.c
> @@ -18,6 +18,8 @@
> struct iio_sysfs_trig {
> struct iio_trigger *trig;
> struct irq_work work;
> + struct delayed_work poll_work;
> + unsigned int poll_interval; /* msec */
> int id;
> struct list_head l;
> };
> @@ -110,10 +112,63 @@ static ssize_t iio_sysfs_trigger_poll(struct device
> *dev,
> return count;
> }
>
> +static void iio_sysfs_trigger_queue_poll_work(struct iio_sysfs_trig *trig)
> +{
> + unsigned long delay;
> +
> + delay = msecs_to_jiffies(trig->poll_interval);
> + if (delay >= HZ)
> + delay = round_jiffies_relative(delay);
> +
> + queue_delayed_work(system_freezable_wq, &trig->poll_work, delay);
> +}
> +
> +static void iio_sysfs_trigger_poll_work(struct work_struct *work)
> +{
> + struct iio_sysfs_trig *trig = container_of(work, struct iio_sysfs_trig,
> + poll_work.work);
> +
> + irq_work_queue(&trig->work);
> + iio_sysfs_trigger_queue_poll_work(trig);
> +}
> +
> +static ssize_t iio_sysfs_trigger_get_poll(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct iio_trigger *trig = to_iio_trigger(dev);
> + struct iio_sysfs_trig *sysfs_trig = iio_trigger_get_drvdata(trig);
> +
> + return sprintf(buf, "%d\n", sysfs_trig->poll_interval);
> +}
> +
> +static ssize_t iio_sysfs_trigger_set_poll(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t count)
> +{
> + struct iio_trigger *trig = to_iio_trigger(dev);
> + struct iio_sysfs_trig *sysfs_trig = iio_trigger_get_drvdata(trig);
> + unsigned int interval;
> + int err;
> +
> + err = kstrtouint(buf, 0, &interval);
> + if (err)
> + return err;
> +
> + sysfs_trig->poll_interval = interval;
> +
> + cancel_delayed_work_sync(&sysfs_trig->poll_work);
> + if (sysfs_trig->poll_interval > 0)
> + iio_sysfs_trigger_queue_poll_work(sysfs_trig);
> +
> + return count;
> +}
> +
> static DEVICE_ATTR(trigger_now, S_IWUSR, NULL, iio_sysfs_trigger_poll);
> +static DEVICE_ATTR(trigger_poll, S_IRUGO | S_IWUSR,
> iio_sysfs_trigger_get_poll,
> + iio_sysfs_trigger_set_poll);
>
> static struct attribute *iio_sysfs_trigger_attrs[] = {
> &dev_attr_trigger_now.attr,
> + &dev_attr_trigger_poll.attr,
> NULL,
> };
>
> @@ -164,6 +219,7 @@ static int iio_sysfs_trigger_probe(int id)
> iio_trigger_set_drvdata(t->trig, t);
>
> init_irq_work(&t->work, iio_sysfs_trigger_work);
> + INIT_DELAYED_WORK(&t->poll_work, iio_sysfs_trigger_poll_work);
>
> ret = iio_trigger_register(t->trig);
> if (ret)
> @@ -198,6 +254,8 @@ static int iio_sysfs_trigger_remove(int id)
> return -EINVAL;
> }
>
> + cancel_delayed_work_sync(&t->poll_work);
> +
> iio_trigger_unregister(t->trig);
> iio_trigger_free(t->trig);
>
>
--
Peter Meerwald
+43-664-2444418 (mobile)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
