[RFC PATCH 3/3] iio: imu: st_lsm6dsx: add wake on accelerometer threshold hook in sysfs

[Sean Nyekjaer <sean@geanix.com>]

This adds a wakeup threshold hook in sysfs, it enables us to
change the threshold value on the run.
For now this is the raw register value...

Signed-off-by: Sean Nyekjaer <sean@geanix.com>
---
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 34 ++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
index 2c8ad7d65d2f..cbcd7920f05d 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -657,12 +657,45 @@ static ssize_t st_lsm6dsx_sysfs_set_wakeup_enabled(struct device *dev,
 	return len;
 }
 
+static ssize_t st_lsm6dsx_sysfs_get_wakeup_threshold(struct device *dev,
+					    struct device_attribute *attr,
+					    char *buf)
+{
+	struct st_lsm6dsx_sensor *sensor = iio_priv(dev_get_drvdata(dev));
+	struct st_lsm6dsx_hw *hw = sensor->hw;
+
+	return sprintf(buf, "%d\n", hw->wake_threshold);
+}
+
+static ssize_t st_lsm6dsx_sysfs_set_wakeup_threshold(struct device *dev,
+					    struct device_attribute *attr,
+					    const char *buf, size_t len)
+{
+	struct st_lsm6dsx_sensor *sensor = iio_priv(dev_get_drvdata(dev));
+	struct st_lsm6dsx_hw *hw = sensor->hw;
+	int threshold;
+
+	if (kstrtoint(buf, 0, &threshold))
+		return -EINVAL;
+
+	if ((threshold < 0) || (threshold > 31))
+		return -EINVAL;
+
+	if (!st_lsm6dsx_set_wake_threshold(hw, threshold))
+		return len;
+
+	return -EINVAL;
+}
+
 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(st_lsm6dsx_sysfs_sampling_frequency_avail);
 static IIO_DEVICE_ATTR(in_accel_scale_available, 0444,
 		       st_lsm6dsx_sysfs_scale_avail, NULL, 0);
 static IIO_DEVICE_ATTR(wakeup_enabled, 0644,
 		       st_lsm6dsx_sysfs_get_wakeup_enabled,
 		       st_lsm6dsx_sysfs_set_wakeup_enabled, 0);
+static IIO_DEVICE_ATTR(wakeup_threshold, 0644,
+		       st_lsm6dsx_sysfs_get_wakeup_threshold,
+		       st_lsm6dsx_sysfs_set_wakeup_threshold, 0);
 static IIO_DEVICE_ATTR(in_anglvel_scale_available, 0444,
 		       st_lsm6dsx_sysfs_scale_avail, NULL, 0);
 
@@ -670,6 +703,7 @@ static struct attribute *st_lsm6dsx_acc_attributes[] = {
 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 	&iio_dev_attr_in_accel_scale_available.dev_attr.attr,
 	&iio_dev_attr_wakeup_enabled.dev_attr.attr,
+	&iio_dev_attr_wakeup_threshold.dev_attr.attr,
 	NULL,
 };
 
-- 
2.22.0