[PATCH v2 13/13] iio: chemical: bme680: add power management

[Vasileios Amoiridis <vassilisamir@gmail.com>]

Add runtime power management to the device. To facilitate this, add also
a struct dev* inside the bme680_data structure to have the device
accesible from the data structure.

Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com>
---
 drivers/iio/chemical/bme680.h      |   2 +
 drivers/iio/chemical/bme680_core.c | 126 +++++++++++++++++++++++++++--
 2 files changed, 121 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/chemical/bme680.h b/drivers/iio/chemical/bme680.h
index e5d82a6d5b59..74e97e35e35a 100644
--- a/drivers/iio/chemical/bme680.h
+++ b/drivers/iio/chemical/bme680.h
@@ -2,6 +2,7 @@
 #ifndef BME680_H_
 #define BME680_H_
 
+#include <linux/pm.h>
 #include <linux/regmap.h>
 
 #define BME680_REG_CHIP_ID			0xD0
@@ -82,6 +83,7 @@
 #define BME680_CALIB_RANGE_3_LEN               5
 
 extern const struct regmap_config bme680_regmap_config;
+extern const struct dev_pm_ops bme680_dev_pm_ops;
 
 int bme680_core_probe(struct device *dev, struct regmap *regmap,
 		      const char *name);
diff --git a/drivers/iio/chemical/bme680_core.c b/drivers/iio/chemical/bme680_core.c
index 2d9d20f203aa..803aa4f14b37 100644
--- a/drivers/iio/chemical/bme680_core.c
+++ b/drivers/iio/chemical/bme680_core.c
@@ -14,6 +14,8 @@
 #include <linux/device.h>
 #include <linux/log2.h>
 #include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 
@@ -823,9 +825,9 @@ static int bme680_read_gas(struct bme680_data *data, int *comp_gas_res)
 	return 0;
 }
 
-static int bme680_read_raw(struct iio_dev *indio_dev,
-			   struct iio_chan_spec const *chan,
-			   int *val, int *val2, long mask)
+static int __bme680_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
 {
 	struct bme680_data *data = iio_priv(indio_dev);
 	int chan_val, ret;
@@ -937,14 +939,30 @@ static int bme680_read_raw(struct iio_dev *indio_dev,
 	}
 }
 
+static int bme680_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct bme680_data *data = iio_priv(indio_dev);
+	struct device *dev = regmap_get_device(data->regmap);
+	int ret;
+
+	pm_runtime_get_sync(dev);
+	ret = __bme680_read_raw(indio_dev, chan, val, val2, mask);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
+	return ret;
+}
+
 static bool bme680_is_valid_oversampling(int rate)
 {
 	return (rate > 0 && rate <= 16 && is_power_of_2(rate));
 }
 
-static int bme680_write_raw(struct iio_dev *indio_dev,
-			    struct iio_chan_spec const *chan,
-			    int val, int val2, long mask)
+static int __bme680_write_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan,
+			      int val, int val2, long mask)
 {
 	struct bme680_data *data = iio_priv(indio_dev);
 
@@ -989,6 +1007,22 @@ static int bme680_write_raw(struct iio_dev *indio_dev,
 	}
 }
 
+static int bme680_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	struct bme680_data *data = iio_priv(indio_dev);
+	struct device *dev = regmap_get_device(data->regmap);
+	int ret;
+
+	pm_runtime_get_sync(dev);
+	ret = __bme680_write_raw(indio_dev, chan, val, val2, mask);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
+	return ret;
+}
+
 static const char bme680_oversampling_ratio_show[] = "1 2 4 8 16";
 
 static IIO_CONST_ATTR(oversampling_ratio_available,
@@ -1091,6 +1125,39 @@ static irqreturn_t bme680_trigger_handler(int irq, void *p)
 	return IRQ_HANDLED;
 }
 
+static int bme680_buffer_preenable(struct iio_dev *indio_dev)
+{
+	struct bme680_data *data = iio_priv(indio_dev);
+	struct device *dev = regmap_get_device(data->regmap);
+
+	pm_runtime_get_sync(dev);
+	return 0;
+}
+
+static int bme680_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	struct bme680_data *data = iio_priv(indio_dev);
+	struct device *dev = regmap_get_device(data->regmap);
+
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+	return 0;
+}
+
+static const struct iio_buffer_setup_ops bme680_buffer_setup_ops = {
+	.preenable = bme680_buffer_preenable,
+	.postdisable = bme680_buffer_postdisable,
+};
+
+static void bme680_pm_disable(void *data)
+{
+	struct device *dev = data;
+
+	pm_runtime_get_sync(dev);
+	pm_runtime_put_noidle(dev);
+	pm_runtime_disable(dev);
+}
+
 int bme680_core_probe(struct device *dev, struct regmap *regmap,
 		      const char *name)
 {
@@ -1164,15 +1231,60 @@ int bme680_core_probe(struct device *dev, struct regmap *regmap,
 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
 					      iio_pollfunc_store_time,
 					      bme680_trigger_handler,
-					      NULL);
+					      &bme680_buffer_setup_ops);
 	if (ret)
 		return dev_err_probe(dev, ret,
 				     "iio triggered buffer setup failed\n");
 
+	/* Enable runtime PM */
+	pm_runtime_get_noresume(dev);
+	pm_runtime_set_autosuspend_delay(dev, BME680_STARTUP_TIME_US * 100);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_set_active(dev);
+	ret = devm_pm_runtime_enable(dev);
+	if (ret)
+		return ret;
+
+	pm_runtime_put(dev);
+
+	ret = devm_add_action_or_reset(dev, bme680_pm_disable, dev);
+	if (ret)
+		return ret;
+
 	return devm_iio_device_register(dev, indio_dev);
 }
 EXPORT_SYMBOL_NS_GPL(bme680_core_probe, IIO_BME680);
 
+static int bme680_runtime_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bme680_data *data = iio_priv(indio_dev);
+
+	return regulator_bulk_disable(BME680_NUM_SUPPLIES, data->supplies);
+}
+
+static int bme680_runtime_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bme680_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = regulator_bulk_enable(BME680_NUM_SUPPLIES, data->supplies);
+	if (ret)
+		return ret;
+
+	fsleep(BME680_STARTUP_TIME_US);
+
+	ret = bme680_chip_config(data);
+	if (ret)
+		return ret;
+
+	return bme680_gas_config(data);
+}
+
+EXPORT_RUNTIME_DEV_PM_OPS(bme680_dev_pm_ops, bme680_runtime_suspend,
+			  bme680_runtime_resume, NULL);
+
 MODULE_AUTHOR("Himanshu Jha <himanshujha199640@gmail.com>");
 MODULE_DESCRIPTION("Bosch BME680 Driver");
 MODULE_LICENSE("GPL v2");
-- 
2.43.0