[PATCH v1 08/13] iio: chemical: bme680: add power management

vamoirid posted 13 patches 1 month, 2 weeks ago
[PATCH v1 08/13] iio: chemical: bme680: add power management
Posted by vamoirid 1 month, 2 weeks ago
From: 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      |   1 +
 drivers/iio/chemical/bme680_core.c | 100 +++++++++++++++++++++++++++--
 2 files changed, 95 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/chemical/bme680.h b/drivers/iio/chemical/bme680.h
index e55a48982b3e..e9e3e08fa366 100644
--- a/drivers/iio/chemical/bme680.h
+++ b/drivers/iio/chemical/bme680.h
@@ -75,6 +75,7 @@
 #define BME680_CALIB_RANGE_3_LEN               5
 
 extern const struct regmap_config bme680_regmap_config;
+extern const struct dev_pm_ops bmp280_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 a2039b966f20..5fd5740bb7fe 100644
--- a/drivers/iio/chemical/bme680_core.c
+++ b/drivers/iio/chemical/bme680_core.c
@@ -14,6 +14,7 @@
 #include <linux/device.h>
 #include <linux/log2.h>
 #include <linux/module.h>
+#include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 
@@ -111,6 +112,7 @@ struct bme680_data {
 	struct regmap *regmap;
 	struct bme680_calib bme680;
 	struct mutex lock; /* Protect multiple serial R/W ops to device. */
+	struct device *dev;
 	u8 oversampling_temp;
 	u8 oversampling_press;
 	u8 oversampling_humid;
@@ -753,9 +755,9 @@ static int bme680_read_gas(struct bme680_data *data, int *val)
 	return IIO_VAL_INT;
 }
 
-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 ret;
@@ -803,14 +805,29 @@ 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);
+	int ret;
+
+	pm_runtime_get_sync(data->dev);
+	ret = __bme680_read_raw(indio_dev, chan, val, val2, mask);
+	pm_runtime_mark_last_busy(data->dev);
+	pm_runtime_put_autosuspend(data->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);
 
@@ -846,6 +863,21 @@ 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);
+	int ret;
+
+	pm_runtime_get_sync(data->dev);
+	ret = __bme680_write_raw(indio_dev, chan, val, val2, mask);
+	pm_runtime_mark_last_busy(data->dev);
+	pm_runtime_put_autosuspend(data->dev);
+
+	return ret;
+}
+
 static const char bme680_oversampling_ratio_show[] = "1 2 4 8 16";
 
 static IIO_CONST_ATTR(oversampling_ratio_available,
@@ -873,6 +905,15 @@ static void bme680_regulators_disable(void *data)
 	regulator_bulk_disable(BME680_NUM_SUPPLIES, supplies);
 }
 
+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)
 {
@@ -887,6 +928,7 @@ int bme680_core_probe(struct device *dev, struct regmap *regmap,
 	data = iio_priv(indio_dev);
 	mutex_init(&data->lock);
 	dev_set_drvdata(dev, indio_dev);
+	data->dev = dev;
 	data->regmap = regmap;
 	indio_dev->name = name;
 	indio_dev->channels = bme680_channels;
@@ -947,10 +989,56 @@ int bme680_core_probe(struct device *dev, struct regmap *regmap,
 		return dev_err_probe(dev, ret,
 				     "failed to set gas config data\n");
 
+	/* Enable runtime PM */
+	pm_runtime_get_noresume(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_set_autosuspend_delay(dev, BME680_STARTUP_TIME_US * 100);
+	pm_runtime_use_autosuspend(dev);
+	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;
+
+	ret = bme680_gas_config(data);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+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
Re: [PATCH v1 08/13] iio: chemical: bme680: add power management
Posted by Andy Shevchenko 1 month, 2 weeks ago
On Thu, Oct 10, 2024 at 11:00:25PM +0200, vamoirid wrote:
> From: 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.

...

> --- a/drivers/iio/chemical/bme680.h
> +++ b/drivers/iio/chemical/bme680.h
> @@ -75,6 +75,7 @@
>  #define BME680_CALIB_RANGE_3_LEN               5
>  
>  extern const struct regmap_config bme680_regmap_config;
> +extern const struct dev_pm_ops bmp280_dev_pm_ops;

Is pm.h being included already in this header? Otherwise you need to add it.

...

>  	struct regmap *regmap;
>  	struct bme680_calib bme680;
>  	struct mutex lock; /* Protect multiple serial R/W ops to device. */
> +	struct device *dev;

Is it the same that you may get wia regmap_get_device()?

>  	u8 oversampling_temp;
>  	u8 oversampling_press;
>  	u8 oversampling_humid;

...

> +	/* Enable runtime PM */
> +	pm_runtime_get_noresume(dev);
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +	pm_runtime_set_autosuspend_delay(dev, BME680_STARTUP_TIME_US * 100);
> +	pm_runtime_use_autosuspend(dev);
> +	pm_runtime_put(dev);

Can we use devm_pm_runtime_enable() for some of the above?

> +	ret = devm_add_action_or_reset(dev, bme680_pm_disable, dev);
> +	if (ret)
> +		return ret;

...

> +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;

> +	ret = bme680_gas_config(data);
> +	if (ret)
> +		return ret;
> +
> +	return 0;

	return bme680_gas_config(...);

> +}

...

> +EXPORT_RUNTIME_DEV_PM_OPS(bme680_dev_pm_ops, bme680_runtime_suspend,
> +			  bme680_runtime_resume, NULL);

You also need pm.h for the macro IIRC.

-- 
With Best Regards,
Andy Shevchenko
Re: [PATCH v1 08/13] iio: chemical: bme680: add power management
Posted by Vasileios Aoiridis 1 month, 2 weeks ago
On Fri, Oct 11, 2024 at 01:10:20PM +0300, Andy Shevchenko wrote:
> On Thu, Oct 10, 2024 at 11:00:25PM +0200, vamoirid wrote:
> > From: 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.
> 
> ...
> 
> > --- a/drivers/iio/chemical/bme680.h
> > +++ b/drivers/iio/chemical/bme680.h
> > @@ -75,6 +75,7 @@
> >  #define BME680_CALIB_RANGE_3_LEN               5
> >  
> >  extern const struct regmap_config bme680_regmap_config;
> > +extern const struct dev_pm_ops bmp280_dev_pm_ops;
> 
> Is pm.h being included already in this header? Otherwise you need to add it.
>

No it is not, and indeed I need to add it. Probably because it was
included by some other file I didn't get an error from gcc?

> ...
> 
> >  	struct regmap *regmap;
> >  	struct bme680_calib bme680;
> >  	struct mutex lock; /* Protect multiple serial R/W ops to device. */
> > +	struct device *dev;
> 
> Is it the same that you may get wia regmap_get_device()?
> 

Yes it is the same. Maybe I can try and see if I can use the following

	regmap_get_device(data->regmap)

in the places where the pm functions are used in order to not declare a
new value inside the struct bme680_data. But in general, is this approach
prefered?

> >  	u8 oversampling_temp;
> >  	u8 oversampling_press;
> >  	u8 oversampling_humid;
> 
> ...
> 
> > +	/* Enable runtime PM */
> > +	pm_runtime_get_noresume(dev);
> > +	pm_runtime_set_active(dev);
> > +	pm_runtime_enable(dev);
> > +	pm_runtime_set_autosuspend_delay(dev, BME680_STARTUP_TIME_US * 100);
> > +	pm_runtime_use_autosuspend(dev);
> > +	pm_runtime_put(dev);
> 
> Can we use devm_pm_runtime_enable() for some of the above?
>

I will have to check its use, and I will let you know.

> > +	ret = devm_add_action_or_reset(dev, bme680_pm_disable, dev);
> > +	if (ret)
> > +		return ret;
> 
> ...
> 
> > +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;
> 
> > +	ret = bme680_gas_config(data);
> > +	if (ret)
> > +		return ret;
> > +
> > +	return 0;
> 
> 	return bme680_gas_config(...);
> 

Indeed, much cleaner, thanks!

> > +}
> 
> ...
> 
> > +EXPORT_RUNTIME_DEV_PM_OPS(bme680_dev_pm_ops, bme680_runtime_suspend,
> > +			  bme680_runtime_resume, NULL);
> 
> You also need pm.h for the macro IIRC.
> 

ACK.

> -- 
> With Best Regards,
> Andy Shevchenko
> 
> 

Cheers,
Vasilis
Re: [PATCH v1 08/13] iio: chemical: bme680: add power management
Posted by Andy Shevchenko 1 month, 2 weeks ago
Fri, Oct 11, 2024 at 09:02:32PM +0200, Vasileios Aoiridis kirjoitti:
> On Fri, Oct 11, 2024 at 01:10:20PM +0300, Andy Shevchenko wrote:
> > On Thu, Oct 10, 2024 at 11:00:25PM +0200, vamoirid wrote:

...

> > > +extern const struct dev_pm_ops bmp280_dev_pm_ops;
> > 
> > Is pm.h being included already in this header? Otherwise you need to add it.
> 
> No it is not, and indeed I need to add it. Probably because it was
> included by some other file I didn't get an error from gcc?

Yeah, it's called a "proxy" header in general meaning. We should try hard not
to use such headers (meaning not to use them in a "proxy" mode).

...

> > >  	struct regmap *regmap;
> > >  	struct bme680_calib bme680;
> > >  	struct mutex lock; /* Protect multiple serial R/W ops to device. */
> > > +	struct device *dev;
> > 
> > Is it the same that you may get wia regmap_get_device()?
> > 
> 
> Yes it is the same. Maybe I can try and see if I can use the following
> 
> 	regmap_get_device(data->regmap)
> 
> in the places where the pm functions are used in order to not declare a
> new value inside the struct bme680_data. But in general, is this approach
> prefered?

Since there is a getter already available, I prefer not to shortcut it via
adding a duplicating information to the data structure.

> > >  	u8 oversampling_temp;
> > >  	u8 oversampling_press;
> > >  	u8 oversampling_humid;

-- 
With Best Regards,
Andy Shevchenko
Re: [PATCH v1 08/13] iio: chemical: bme680: add power management
Posted by Jonathan Cameron 1 month, 2 weeks ago
On Fri, 11 Oct 2024 21:02:32 +0200
Vasileios Aoiridis <vassilisamir@gmail.com> wrote:

> On Fri, Oct 11, 2024 at 01:10:20PM +0300, Andy Shevchenko wrote:
> > On Thu, Oct 10, 2024 at 11:00:25PM +0200, vamoirid wrote:  
> > > From: 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.  
> > 
> > ...
> >   
> > > --- a/drivers/iio/chemical/bme680.h
> > > +++ b/drivers/iio/chemical/bme680.h
> > > @@ -75,6 +75,7 @@
> > >  #define BME680_CALIB_RANGE_3_LEN               5
> > >  
> > >  extern const struct regmap_config bme680_regmap_config;
> > > +extern const struct dev_pm_ops bmp280_dev_pm_ops;  
> > 
> > Is pm.h being included already in this header? Otherwise you need to add it.
> >  
> 
> No it is not, and indeed I need to add it. Probably because it was
> included by some other file I didn't get an error from gcc?
> 
> > ...
> >   
> > >  	struct regmap *regmap;
> > >  	struct bme680_calib bme680;
> > >  	struct mutex lock; /* Protect multiple serial R/W ops to device. */
> > > +	struct device *dev;  
> > 
> > Is it the same that you may get wia regmap_get_device()?
> >   
> 
> Yes it is the same. Maybe I can try and see if I can use the following
> 
> 	regmap_get_device(data->regmap)
> 
> in the places where the pm functions are used in order to not declare a
> new value inside the struct bme680_data. But in general, is this approach
> prefered?

slightly by me.  I tend not to poke on that if people have chosen a local
variable, but it is a little neater.

This patch might get caught up in an effort to simplify the
autosuspend handling but if it is we'll deal with that whilst merging.
There 'should' be a clean path to transition from this style to the proposed
new one where a simple pm_runtime_put() without the mark_last_busy stuff
is enough for autosuspend cases.

Jonathan