[PATCH v4 09/11] iio: accel: adxl313: implement power-save on inactivity

[Lothar Rubusch <l.rubusch@gmail.com>]

Link activity and inactivity to indicate the internal power-saving state.
Add auto-sleep to be linked to inactivity.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl313.h      |  3 +++
 drivers/iio/accel/adxl313_core.c | 20 ++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/drivers/iio/accel/adxl313.h b/drivers/iio/accel/adxl313.h
index d7e8cb44855b..75ef54b60f75 100644
--- a/drivers/iio/accel/adxl313.h
+++ b/drivers/iio/accel/adxl313.h
@@ -41,6 +41,9 @@
 #define ADXL313_RATE_BASE		6
 
 #define ADXL313_POWER_CTL_MSK		BIT(3)
+#define ADXL313_POWER_CTL_INACT_MSK	GENMASK(5, 4)
+#define ADXL313_POWER_CTL_LINK		BIT(5)
+#define ADXL313_POWER_CTL_AUTO_SLEEP	BIT(4)
 
 #define ADXL313_RANGE_MSK		GENMASK(1, 0)
 #define ADXL313_RANGE_MAX		3
diff --git a/drivers/iio/accel/adxl313_core.c b/drivers/iio/accel/adxl313_core.c
index c5767d56b0cb..1598562a38e2 100644
--- a/drivers/iio/accel/adxl313_core.c
+++ b/drivers/iio/accel/adxl313_core.c
@@ -396,6 +396,7 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 	unsigned int axis_ctrl;
 	unsigned int threshold;
 	unsigned int inact_time_s;
+	int act_en, inact_en;
 	bool en;
 	int ret;
 
@@ -431,6 +432,25 @@ static int adxl313_set_act_inact_en(struct adxl313_data *data,
 	if (ret)
 		return ret;
 
+	/*
+	 * Set sleep and link bit only when ACT and INACT are enabled.
+	 */
+	act_en = adxl313_is_act_inact_en(data, ADXL313_ACTIVITY);
+	if (act_en < 0)
+		return act_en;
+
+	inact_en = adxl313_is_act_inact_en(data, ADXL313_INACTIVITY);
+	if (inact_en < 0)
+		return inact_en;
+
+	en = en && act_en && inact_en;
+
+	ret = regmap_assign_bits(data->regmap, ADXL313_REG_POWER_CTL,
+				 (ADXL313_POWER_CTL_AUTO_SLEEP | ADXL313_POWER_CTL_LINK),
+				 en);
+	if (ret)
+		return ret;
+
 	return adxl313_set_measure_en(data, true);
 }
 
-- 
2.39.5